[V LIBRARt INN W MN “WNW“ Michigan State 553 . . 3 1293 3700992 University This is to certify that the thesis entitled RECOVERY OF 15N FROM ALFALFA RESIDUE IN SOIL, MICROBIAL BIOMASS AND A SUBSEQUENT CORN CROP presented by Glendon Hamilton Harris, Jr. has been accepted towards fulfillment of the requirements for M.S. Crop and Soil Sciences degree in (Linc: VZ/OH 7/720 Major professor Oran B. Hesterman Date February 23, 1988 0-7639 MS U is an Affirmative Action/Equal Opportunity Institution MSU LIBRARIES .——. b RETURNING MATERIALS: Place in book drop to remove this checkout from your record. FINES will be charged if book is returned after the date stamped below. J M1 1.13 2000 77“ .J .1 h ." :3 - 4/04“. RECOVERY OF 15N FROM ALFALFA RESIDUE IN SOIL, MICROBIAL BIOMASS AND A SUBSEQUENT CORN CROP By Glendon Hamilton Harris, Jr. A THESIS Submitted to Michigan State University in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE Department of Crop and Soil Sciences 1988 ABSTRACT RECOVERY OF 15N FROM ALFALFA RESIDUE IN SOIL, MICROBIAL BIOMASS AND A SUBSEQUENT CORN CROP By Glendon Hamilton Harris, Jr. Recent economic and environmental concerns have caused renewed interest in using legumes to provide N to subsequent crops in rotation. The objective of this study was to quantify the recovery of 15N from alfalfa residue in soil, microbial biomass and subsequent corn crop. 15N—labeled alfalfa shoots or roots/crowns were incorporated into field microplots in Fall, 1985, and Spring, 1986, at two Michigan locations. Corn and soil were harvested from the microplots in Fall, 1986, and analyzed for 15N. Corn recovered 16.7 and 25.0 % of the alfalfa~15N applied to loam and sandy loam soils, respectively. Recovery from soil averaged 45.5 % of N input, of which 94.5 % was recovered from the organic fraction. Recovery in microbial biomass accounted for 22.5 % of that recovered in the soil organic fraction. More 15N was recovered from shoots than roots/crowns at both locations and from spring- incorporated than fall-incorporated residues on the loam soil. "This one goes out to the one I love" 111 ACKNOWLEDGMENTS I wish to express my sincere appreciation to my major professor, Dr. Oran B. Hesterman, for giving me the opportunity to work on this project and for the constant assistance and guidance it took to graduate his first student. Thanks goes to my committee, Drs. E.A. Paul, S.K. Ries and J.M. Tiedje, for their input and guidance. I thank my parents for their continued support. I thank my fellow graduate students, especially Todd Williams, John Durling and Tim Griffin for their ideas, camaraderie and hours of hard labor. The assistance of Dave Harris (15N analyses), farm managers Brian Graff and Jim Bronson (at EL and KBS, respectively), Eric Frahm, and undergraduates, Cindy McGinness, Aaron Caruso and Renee Hodges is also greatly appreciated. I would like to recognize Bob Dylan, Van Morrison and R.E.M. for providing inspiration and insight on life and how to live it. Last but not least, I thank Mary Swiontoniowski and Nittany for their unbridled support and friendship, without which the completion of this degree would not have been possible. iv PREFACE This thesis is written as a manuscript in the style required for publication in Agronomymlgurnal. TABLE OF CONTENTS Page LIST OF TABLES ........................................ vii INTRODUCTION ............................................ 1 LITERATURE REVIEW ....................................... 2 Fertilizer Replacement Value Method ................ 2 15N Tracer Method .................................. 3 MATERIALS AND METHODS ................................... 6 RESULTS AND DISCUSSION ................................. 12 CONCLUSIONS ...... . ...................................... 19 LIST OF REFERENCES ..................................... 21 APPENDIX A ............................................. 33 APPENDIX B ............................................. 58 APPENDIX C ............................................. 65 vi Table A1. A2. A3. A4. A5. A6. LIST OF TABLES Page Soil characteristics and climatological data for East Lansing (EL) and Kellogg Biological Station (KBS) .................................... 25 Recovery of alfalfa-15N by corn and in soil at EL ............................................ 26 Recovery of alfalfa-15N by corn and in soil at KBS ........................................... 27 Effect of plant part and time of incorporation on corn dry matter yield and total N uptake at EL and KBS .................................... 28 N mineralization potential and percent mineralized N derived from alfalfa for fresh soil sampled from the 0-15 cm layer after corn harvest at‘EL and KBS ............................ 29 Percent N in corn (grain + stover + roots) derived from alfalfa at EL and KBS ............... 30 Recovery of alfalfa-15N (% of input) in total, inorganic and organic soil N by depth at EL and KBS .................................... 31 Dry matter yield, N content, total N uptake, percent N derived from alfalfa, and recovery of alfalfa-15N by barley (grain + stover (straw) + roots) grown in 1987 after corn at EL and KBS ..... 32 Corn dry matter yield, N content, and total N uptake at EL ..................................... 38 Corn dry matter yield, N content, and total N uptake at KBS .................................... 39 Recovery of alfalfa N—15 by corn at EL ........... 40 Recovery of alfalfa N-15 by corn at KBS .......... 41 Percent corn N derived from alfalfa at EL ........ 42 Percent corn N derived from alfalfa at KBS ....... 43 vii Table A7. A8. A9. A10. A11. A12. A13. A14. A15. A16. A17. A18. A19. A20. B1. B2. Page Recovery of alfalfa N-15 in total soil N at EL ............................................... 44 Recovery of alfalfa N-15 in total soil N at KBS .............................................. 45 Recovery of alfalfa N-15 in inorganic soil N at EL ............................................ 46 Recovery of alfalfa N—15 in inorganic soil N at KBS ........................................... 47 Microbial biomass carbon at EL ......... , ......... 48 Microbial biomass carbon at KBS .................. 49 Microbial biomass N and recovery of alfalfa N-15 in microbial biomass at EL .......... 50 Microbial biomass N and recovery of alfalfa N-15 in microbial biomass at KBS ......... 51 N-15 atom % of total N and inorganic N in soil samples from the 60—75 cm depth at EL and KBS .............................................. 52 N mineralization potential and percent mineralized N derived from alfalfa at EL and KBS .............................................. 53 Spring barley dry matter yield, N content, percent N derived from alfalfa, and total N uptake at EL ..................................... 54 Spring barley dry matter yield, N content, percent N derived from alfalfa, and total N uptake at KBS .................................... 55 Recovery of alfalfa N—15 by spring barley at EL ............................................ 56 Recovery of alfalfa N-15 by spring barley at KBS ........................................... 57 Corn dry matter yield, N content and recovery of fertilizer N—15 by corn at EL and KBS ......... 60 Recovery of fertilizer N—15 in total soil N at EL and KBS .................................... 61 viii Table B3. B4. BS. C1. C2. Page Recovery of fertilizer N-15 in inorganic soil N at EL and KBS .................................. 62 Microbial biomass carbon at EL and KBS ........... 63 Microbial biomass N and recovery of fertilizer N-15 in microbial biomass at EL and KBS .......................................... 64 N fertilizer replacement value data at EL ....... 67 N fertilizer replacement value data at KBS ....... 68 ix INTRODUCTION For economic and environmental reasons, there has been a renewed interest in using legumes in crop rotations to provide N to subsequent non-legume crops. The importance of accurately assessing legume N contributions has therefore increased. Despite considerable past research, debate continues over both the amount of legume N contributed to subsequent crops and the methods of measuring this contribution. Two methods used to quantify legume N contributions to subsequent crops are the fertilizer replacement value method and the 15N tracer method. Numerous fertilizer replacement value studies have been conducted to measure the alfalfa (Mbdicago sativa L.) N contribution to corn (Zea mays L.). This is the first study to measure the alfalfa N contribution to corn using 15N. The objectives were i) to quantify the amount of incorporated alfalfa—15N recovered by a subsequent corn crop and in various soil fractions (total N, inorganic N, organic N and microbial biomass N) and ii) to determine the effect of plant part (shoots vs. roots/ crowns) and time of incorporation (fall vs. spring) on recovery of alfalfa—15N. LITERATURE REVIEW FertilizeLReRlacemenLlaluLMethod Most fertilizer recommendations base legume N credits on the fertilizer replacement value, which is the amount of inorganic N fertilizer required to produce a subsequent non-legume crop yield equivalent to that produced following a legume. Fertilizer replacement value estimates of alfalfa (Mbdicagb sativa L.) N contribution to a subsequent corn (Zéa mays L.) crop range from 31 (Stickler et al., 1959) to 180 (V055 and Shrader, 1979) kg N ha'1 depending on alfalfa cultivar, harvest management and age of the stand. A good stand of alfalfa is commonly credited with 112 to 156 kg N ha‘1 (Bundy, 1985; Jokela et al., 1981; V055 and Shrader, 1984; Warncke et al., 1985 ). While these recommendations give an indication of expected corn grain yield response to a preceding alfalfa crop in terms of an inorganic N fertilizer application, it is assumed that the entire response is due to legume N, and that legume N and inorganic fertilizer N are equally available. Evidence exists disputing both of these assumptions. Several researchers have concluded that beneficial non-N, or "rotation", effects contribute to the yield response of a non-legume following a legume in rotation (Bruulsema and Christie, 1987; Heichel et al., 1987; Hesterman et. al., 1987; Russell et al., 1987; V055 and Shrader, 1984). In one study, up to 25 % of a non-legume yield response to a legume was attributed to such effects (Baldock et al., 1981). Several reports suggest that legume N and inorganic N fertilizer are not equally available for crop uptake. Fribourg and Johnson (1956) reported that alfalfa N is utilized by corn 34 % as efficiently as NH4N03-N. In a direct comparison of legume N and fertilizer N use efficiencies, Ladd and Amato (1986) found that wheat (Triticum aestivum L.) utilized 46 % of applied fertilizer N compared to 17 % of legume N applied at the same rate. Field studies indicate that crops recover about 50 % of applied inorganic fertilizerrl5N (Hauck, 1971). Typical fertilizer N use efficiency values for corn range from 40 to 70 % (Stanford, 1973). Kitur et al. (1984) reported 36 and 62 % recovery of 15N-labeled NH4N03 by corn (grain and stover) depending on application rate and tillage system. Bigeriego et al. (1979) found that corn (grain and stover) recovered between 48 and 81 % 15N-labeled (NH4)ZSO4 depending on application rate and time of application. liNlIraceLMethed Another method of quantifying legume N contributions is to trace 15N from labeled residues into a subsequent crop. In the first reported study using 15N-labeled residues, Norman and Werkman (1943) found that 25 % of 15N from soybean [Gflycine max L. (Merr.)] shoots was recovered by soybean plants growing in pots in a greenhouse. Moore (1974) reported a 30 % recovery of rhodesgrass (Chloris gayana)‘15N by two subsequent rhodesgrass cuttings grown in greenhouse pots. Yaacob and Blair (1980) measured the recovery of 15N from either soybean shoots (minus beans) or sirato (Mbcroptilium atropurpureum) shoots by rhodesgrass in greenhouse pots containing soil previously cropped with 1, 3 or 6 years of soybeans and sirato, respectively. Rhodesgrass recovered an average of 15 % of the soybean-15N regardless of previous cropping history, whereas 14, 42 and 55 X of sirat0’15N was recovered by rhodesgrass with 1,3 and 6 previous sirato crops, respectively. Higher recovery of 15N from sirato compared to soybean was attributed to either the higher N content of sirato or difference in chemical composition of the two materials. The higher recovery of sirat0‘15N in soil with more years of sirato cropping was attributed to an increased priming effect, or stimulated release of native soil organic matter caused by addition of organic residues, and ultimately to the nitrogen content and chemical composition of organic matter of the soils. Azam et al. (1985) found that corn growing in greenhouse pots recovered about 5 % of incorporated Sesbania aculeata (Pers.)'15N. In a field study, Vallis (1983) found that after one year, 7 to 10 % of 15N from surface applied sirato and desmodium (Dasmodium intortum) stems and leaves was recovered by a rhodesgrass pasture in Australia. Sirato contributed more 15N than Desmodium, and leaves of both legumes contributed more 15N than stems. Also in Australia, Ladd et al. (1981, 1983, 1986) have reported between 11 and 28 % recovery of 1SN from incorporated medic (Mbdicago littoralis L.) residues by wheat growing in the field. From these studies, Ladd et al. concluded that the primary value of the legume was long term maintenence of soil organic N levels high enough for adequate delivery of N to future cereal crops. Tracing 15N from applied residues and inorganic fertilizer gives a direct measurement of N contributed to a subsequent crop. However, this method does not account for N initially released from the microbial biomass, nor the soil N accumulated under the legume stand, as contributions from the legume. Jansson and Persson (1976) stated that lower recoveries are expected when measuring fertilizer-15N uptake by crops compared to when using the conventional method of measuring the difference_in crop uptake of N between a fertilized treatment and an unfertilized control. They attribute the lower recoveries using 15N to either a priming effect, in which fertilizer N leads to an increase in net mineralization of soil N, or mineralization— immobilization turnover (MIT), the continuous transfer of inorganic soil N to organic N, and vice versa, by the soil microbial biomass. MATERIALS AND METHODS This study was conducted at two Michigan locations; the Michigan State University Experiment Station at East Lansing (EL), and the Kellogg Biological Station (KBS) at Hickory Corners. Soil types were a Capac loam (fine-loamy, mixed, mesic, Aeric Ochraqualf) and Oshtemo sandy loam (coarse-loamy, mixed, mesic Typic Hapludalf) at EL and KBS, respectively. The previous crop at both sites was alfalfa (EL - 5 yr, KBS - 1 yr). Soil characteristics and climatological data for each location appear in Table 1. 15N—enriched alfalfa shoots (8.1 % atom excess,-C:N 2 13:1) or roots/crowns (6.9 % atom excess, C:N = 22:1) were applied to field microplots in both Fall, 1985, and Spring, 1986 (11 and 14 Nov or 19 and 25 May at EL and KBS, respectively). Labeled residues were obtained by growing 'Vernal' alfalfa in a sand-filled greenhouse bench and fertilizing weekly with a nutrient solution containing K15N03 (12 % atom excess). Residues were incorporated to a 15 cm depth at a rate equivalent to 112 kg N ha'l. Microplots consisted of 0.60 m dia. by 0.60 m deep undisturbed soil columns enclosed by open-ended sheet metal cylinders that extended 5 cm above the soil surface. The cylinders were spaced at least 1.5 m apart and were installed by trenching around the soil column with a gas- powered posthole digger. The top 15 cm of soil was excavated and existing alfalfa roots were removed by handpicking and sieving (0.4 cm). 15N-enriched alfalfa residues (cut to 7 cm lengths) were mixed into the sieved soil and returned to microplots. Unlabeled alfalfa residues were incorporated into separate, 15 cm-deep, microplots in 2 of 4 replications to provide 15N backround levels. In spring (2 and 8 May at EL and KBS, respectively), 1986, 6 corn seeds ('Pioneer 3737') were hand-planted into each microplot, and thinned to 3 plants soon after emergence. The area surrounding the microplots was planted with the same hybrid at a population of 59 000 plants ha‘l. One week prior to planting, both sites were sprayed with 2.24 kg a.i. ha'l glyphosate [N-(phosphonomethyl) glycine] to kill the existing alfalfa. At planting, 28 kg ha‘1 P205 (0-46—0) was broadcast at the EL site as recommended by the Michigan State Soil Testing Lab. At planting, both locations received 0.56 kg a.i. ha“1 paraquat (1,1’- dimethyl-4,4'-bipydridinium ion) , 2.8 kg a.i. ha‘l alachlor [2—chloro-2'-6'-diethyl-N—(methoxymethyl) acetanilide], 1.4 kg a.i. ha'l cyanizine (2-{[4-chloro-6— (ethylamino)-1,3,5-triazine-2-yl] amino}-2- methylpropanenitrile) and, 0.56 kg a.i. ha"1 atrazine [6- chloro-N-ethyl-N'-(1-methylethyl)-1,3,5-triazine—2,4- diamine] to control weeds throughout the growing season. During the growing season, microplots received no supplemental N, and any weeds emerging in the microplots were pulled and left on the surface. After corn plants had reached physiological maturity (6 and 14 Oct at EL and KBS, respectively), corn grain, stover (stalks + cobs), and roots were harvested from each microplot. Roots were harvested from the 0-15 cm layer of soil by handpicking and sieving (0.4 cm), then washed with tap water before drying. All harvested plant material was dried at 60 °C for 4 days, weighed, and ground to pass a 40 mesh screen. Samples were analyzed for total N by micro-Kieldahl digestion (Bremner, 1965) and colorimetric determination of NH4+ in a Lachat flow-injection autoanalyzer by Lachat QuikChemT-M- Method No. 10-107—06—2-E (Lachat Chemicals, Inc.). Plant samples were analyzed for 15N on a Micromass 622 mass spectrometer after a micro-Kjeldahl digestion and steam distillation of NH3. Percent N in corn derived from alfalfa was calculated by : 15N atom % excess corn / 15N atom % excess alfalfa x 100. Recovery of alfalfa-15N by corn calculated by : percent N in corn derived from alfalfa x corn total N uptake / amount of alfalfa N applied; where corn total N uptake = corn dry matter yield x N content. After harvesting roots from the entire 0-15 cm soil layer of each microplot, 3 consecutive soil layers of 15 cm depth (15-30, 30-45, 45-60 cm) were excavated from half of the microplots. Each layer was weighed, mixed, and sampled. Subsamples were dried for 4 days at 60 °C to determine moisture content. Dried subsamples were then analyzed for total N and 15N on a Europa Scientific Tracermass mass spectrometer after conversion of sample N to N2 by Dumas combustion in a Roboprep CN analyzer (Preston and Owens, 1983). Soil inorganic N (N03‘ and NH4+) in filtered KCl extracts (100 ml 2 M KCl : 20 g dry soil, shaken 1 hr) was measured colorimetrically on the Lachat flow—injector analyzer by Lachat QuikChemT-M- method no. 12—107-04-1-A (Lachat Chemicals, Inc.). Soil inorganic 15N in KCl extracts was released as NHa following reduction of N03‘ with Devarda's alloy and addition of MgO. The released NHa was trapped on acidified glass filter disks (6 mm) as NH4+ (Brooks, 1987). The 15NH4+ was analyzed on the Europa Scientific Tracermass after combustion of the filter disks in the Roboprep CN analyzer. Recovery of alfalfa—15N in total and inorganic soil N was calculated by an equation similar to that used to calculate recovery by corn. Recovery in the organic soil N fraction was calculated by subtraction (total - inorganic). Microbial biomass C and N in fresh samples from the 0— 15 soil layer of each microplot were determined by the chloroform fumigation-incubation method (Jenkinson and Powlson, 1976). Soils were not inoculated after fumigation; biomass C = Cf/Kc, where CE = COz—C evolved from the fumigated sample and Kc : 0.41; and biomass N = Nf/Kn, where Nf = NH4+-N released during incubation after fumigation and Kn = — 0.014(C£/N£) + 0.39 (Voroney and 10 Paul, 1980). N: and 15N£ were determined as described above for inorganic soil N and 15N, and then used to calculate recovery of alfalfa—15N in microbial biomass. N mineralization potential and percent mineralized N derived from alfalfa were also determined for the fresh subsample taken from the 0-15 cm soil layer after corn harvest. The amount of N03‘ and NH4+ mineralized during a 20—day aerobic incubation at 25 0C (measured in KCl extracts as previously described) was taken as the N mineralization potential (Ladd et al., 1983). The percent of mineralized soil N derived from alfalfa was calculated after analyzing the inorganic N in KCl extracts for 15N by the method described above. To detect leaching of inorganic N from alfalfa residues below 0.60 m, 5 core samples (2.5 cm dia.) from the 60-75 cm soil layer of each microplot were pooled and analyzed for 15N. Analysis of variance for a randomized complete block (4 replications), 2 x 2 factorial experiment was performed on all data. Factors included alfalfa plant part incorporated (shoots or roots/crowns) and time of incorporation (fall or spring). Locations were analyzed separately. Spring barley (Hbrdeum vulgare L.) was planted in all microplots at EL and KBS in Spring, 1987 (10 and 17 April, respectively) to measure recovery of alfalfa-15N by a second subsequent crop. After sampling in Fall 1986, soil 11 was returned by layer to the microplots, which were left fallow over winter. No additional N was applied to the microplots during 1987. After the barley reached physiological maturity (14 and 23 Jul at EL and KBS, respectively), grain, stover (straw) and roots were harvested from each microplot and analyzed for 15N on the Europa Scientific Tracermass. Recovery of alfalfa-15N by barley was then calculated by the same equation used for recovery by corn. RESULTS AND DISCUSSION Corn (grain + stover + roots) recovered 16.7 and 25.0 % of applied alfalfa-15N at EL and KBS, respectively (Tables 2 and 3). These results are comparable to other legume—15N decomposition and recovery studies (Azam, 1985; Moore, 1974; Norman and Werkman, 1943; Vallis, 1983; Yaacob and Blair, 1980), and agree especially well with those reported by Ladd et al. (1981, 1983, 1986) who also incorporated a Mbdicago species into field soil and found between 11 and 28 % recovery by wheat. Sixty, 37 and 3 % of the alfalfa-15N recovered by corn was found in the grain, stover and roots, respectively, at EL. Sixty—four, 33 and 3 % was found in the grain, stover, and roots, respectively, at KBS. The above-stated recovery of alfalfa—15N by corn roots may be an underestimate because we did not attempt to separate fine root material from the 0-15 cm soil layer, nor any roots from soil in deeper layers. Another indication that not all roots were separated from soil comes from a previous study conducted in Michigan. Foth (1962) found that over 75 % of corn root dry matter yield occured in the top 22.5 cm of soil, and shoottroot dry weight ratios for mature corn were approximately 11:1. Using data from Table 4, corn shoot: root dry weight ratios for EL and KBS were 15:1 and 20:1, 12 13 respectively. However, 1SN in corn roots not separated from soil was included in soil sampled from that layer. The higher recovery of alfalfa-15N by corn at KBS compared to EL was not due to differences in corn dry matter yield or total N uptake between the 2 locations (Table 4). Instead, the higher recovery was due to a smaller, more active, mineralizable soil N pool at KBS compared to EL. This resulted in both a greater contribution of alfalfa-15N to the mineralizable N pool (on a percentage basis), and higher turnover of alfalfa-15N through the mineralizable N pool at KBS compared to EL. The lower N and OM content of the KBS soil (Table 1) indicates that the mineralizable soil N pool at KBS was smaller than at EL. The higher percent mineralized N derived from alfalfa (for fresh soil sampled from the 0-15 cm layer after corn harvest) at KBS (Table 5) indicates the percentage contribution to the mineralizable N pool was greater at KBS than at EL. The higher N mineralization capacity at KBS suggests higher turnover of alfalfa-15N through the mineralizable N pool compared to FL. Therefore, corn (grain + stover + roots) derived more N from alfalfa at KBS compared to EL (Table 6). And since corn dry matter yields were the same at both locations, there was higher recovery of alfalfa-15N at KBS. The above-stated explanation for higher recovery of alfalfa-15N by corn at KBS is supported by results of Ladd et al. (1983) who also reported a greater percentage 14 contribution of legume-15N to the mineralizable soil N pool for topsoil with low (0.9 g kg‘l), compared to high (1.7 g kg"1 ), total N content. The higher recovery of alfalfa- 15N by corn on the coarser textured soil at KBS is also supported by Hesterman et al. (1987) who found that more alfalfa N was recovered by corn growing on a coarse textured than a fine textured soil. Corn recovered more 1'5N from alfalfa shoots than roots/crowns at both EL and KBS (Tables 2 and 3; F values significant at the 0.05 and 0.10 levels of probability at EL and KBS, respectively). The higher CIN ratio of roots/crowns compared to shoots probably resulted in slower decomposition and availablity of N for uptake by corn. The rate of residue decomposition decreases as C:N ratio increases (Parr and Papendick, 1978). Bruulsema and Christie (1987) suggested that the composition of plant material (including C : N ratio) may have as much influence on N release to soil as the total N yield of the plowdown crop itself. Time of incorporation had no significant effect on recovery of alfalfa-15N by corn at KBS (Table 4). At EL, more 15N was recovered by corn from spring—incorporated than fall—incorporated alfalfa (Table 3; F value significant at the 0.05 level of probability). This result could have been due to better temporal synchrony, i.e. more timely N release or mineralization from the alfalfa residues for uptake by corn when spring-incorporated. 15 Recovery of alfalfa-15N in soil after corn harvest at EL and KBS measured 47.8 and 43.3 % of the initial input, respectively (Tables 2 and 3). Most of the alfalfa—15N recovered in soil was found in the organic fraction (97 and 94 % at EL and KBS, respectively). In other legume—15N field studies, Ladd et al. (1981, 1983, 1986) and Vallis (1983) also reported that most of the legume-15N recovered from soil had been incorporated into the organic fraction. Plant part and time of incorporation factors had a similar effect on recovery of alfalfa-15N in soil as in corn : more alfalfa-15N was recovered from shoots vs. roots/crowns at both locations, time of incorporation had no effect on recovery of alfalfa—15N at KBS, and more 15N was recovered when alfalfa was incorporated in the spring vs. fall at EL (Tables 2 and 3). Recovery of alfalfa-15N in soil microbial biomass was higher at EL compared to KBS (Tables 2 and 3). The higher recovery at EL was related to the longer legume cropping history and higher soil OM levels compared to KBS. Bolton et al. (1985) reported that a soil with a long legume cropping history (almost 80 years, and with no inorganic N applications) had a larger microflora population than a soil which received anhydrous ammonia as a N source for at least 30 years. Schnurer et al. (1985) found that microbial biomass C and N were positively correlated with soil organic matter. The microbial biomass C and N contents of the soil at EL measured 545 and 88 ug g-l 16 respectively compared to 291 ug C g“1 and 48 ug N g'1 at KBS. Microbial biomass-15N accounted for 24 and 21 % of alfalfa-15N recovered in the organic soil fraction (0-15 cm) at EL and KBS, respectively. Total recovery of alfalfa-ISN (corn + soil), averaged 64.5 and 68.3 % of input at EL and KBS. There was no time of incorporation effect on total recovery of alfalfa—15N at KBS on a sandy loam soil, but on the loam soil at EL, total 15N recovery was higher from spring-incorporated than fall- incorporated alfalfa (75 vs. 54 %; F value significant at the 0.05 level of probability). In a lysimeter study conducted in Alabama, Jones (1933) reported as much as 70 % loss (by leaching) of soybean-, cowpea (Vigna sinensis)-, and crotalaria (crotalaria spectabilis)-N when fall- incorporated. Nitrogen loss from these legumes was reduced by almost 50 % when spring-incorporated. Most of the alfalfa-15N not recovered at EL was likely lost from microplots by denitrification. Above average rainfall during the growing season and poorly- drained, fine-textured soil at this site created conditions favorable for denitrification. Although alfalfa-15N was detected in the 60-75 cm soil layer (0.02583 atom % excess in inorganic fraction; 0.00412 atom % excess in total N fraction), indicating some loss by leaching, denitrification is still suspected as the major loss mechanism. Leaching of N03‘—N from alfalfa residues below the 60 cm microplots is the major mechanism of loss 17 suspected at KBS, where alfalfa-15N was also detected in soil samples from the 60-75 cm depth at KBS (0.02274 atom % excess in inorganic fraction; 0.01366 atom % excess in total N fraction). Above average rainfall during the growing season and well—drained, coarse—textured soil at this site combined to create conditions conducive to leaching. Total 15N recovery at EL and KBS was lower than that reported in field studies by Ladd et al. (1981, 1983, 1986), suggesting there is more loss of legume-N from an alfalfa-corn rotation in Michigan, with a temperate climate than a medic—wheat rotation in the arid conditions of Australia. Ladd et al. (1981) also attributed losses of legume-15N to denitrification on a fine-textured soil and leaching on a coarse-textured soil. Distribution of alfalfa-15N recovered in soil, by depth, (Table 7) shows that 94 % recovery from the organic fraction and 90% recovery from the inorganic fraction occured in the top 30 cm. Distribution of inorganic alfalfa—15N in the soil profile at both locations does not indicate leaching from the system at the time of sampling (fall). However, lack of large amounts of inorganic 15N in lower depths at KBS does not eliminate the possibility of significant leaching earlier in the season. A portion of the alfalfa-15N recovered in the organic soil N fraction at the lower depths was probably contained in corn roots not separated from soil as discussed earlier. l8 Tracing alfalfa-15N into a second subsequent crop, only 1 % was recovered by the 1987 spring barley crop at both EL and KBS (Table 8). This result is also compatable with other legume-15N studies. Ladd et al. (1983) reported 4 % recovery of medic—15N by a second wheat crop and Vallis (1983) found that uptake of 15N from sirato and desmodium by rhodesgrass in second and third years was only 23 and 12 % respectively of that in the first year. Poor stand establisment resulted in low dry matter yield by barley at KBS compared to EL (Table 8). However, 'recovery of alfalfa-15N by barley was almost identical at the two locations due to the higher N content and percent N derived from alfalfa at KBS compared to EL. The higher N content and percent N derived from alfalfa by barley at KBS further suggests that the mineralizable soil N pool was smaller and more active than at EL, again causing a greater contribution of alfalfa-15N to the mineralizable N pool and higher turnover of alfalfa—15N through that pool. CONCLUSIONS Results for recovery of alfalfa-15N by corn at EL and KBS compare well with other legume—15N studies in which less than 30 % of legume N was contributed to a subsequent non—legume crop. These recovery values are lower than those for recovery of fertilizer—15N reported earlier. Also, assuming a typical quantity of 112 kg N h‘1 returned to soil in alfalfa residues, the 15N recovery values at EL and KBS would translate to alfalfa N contributions of 19 and 28 kg N h'l, respectively. These values for N contribution based on the 15N tracer method are low compared to the alfalfa N credit of 112 to 156 kg N h’1 based on fertilizer replacement value studies. The reason for this large discrepancy is that the fertilizer replacement value method measures the overall effect of alfalfa on corn yield in terms of an inorganic N fertilizer application, whereas the 15N method measures recovery of N from alfalfa residues (and not from the resident microbial biomass N pool or soil N accumulated under the alfalfa stand). More alfalfa 15N was incorporated into the soil organic N pool than was recovered by corn. This indicates that the alfalfa N contribution to maintenance of soil N levels for adequate N release to future crops is as 19 20 important, if not more so, than the contribution to the first subsequent crop. Recovery of legume N by crops suceeding the first subsequent crop however are very low, as suggested by the results of this study and those reported by Ladd et al. (1983) and Vallis (1983) mentioned earlier. Total alfalfa-15N recovery values from this study suggest that approximately 30 % of N from alfalfa residues may be lost by leaching or denitrification. Since there was higher recovery of 15N from spring-incorporated alfalfa by corn and in soil at EL, it may be advantageous to incorporate alfalfa residues in the spring vs. fall for more efficient N use. L IST OF REFERENCES LIST OF REFERENCES Azam, F., K.A. Malik, and M.I. Sajjad. 1985. Transformation in soil and availability to plants of 15N applied as inorganic fertilizer and legume residues. Plant Soil. 86 3- 13. Bigeriego, M., Hauck, R.D., and R.A. Olsen. 1979. Uptake, translocation and utilization of 15N—depleted fertilizer in irrigated corn. Agron. J. 43:528-533. Bolton, H., L.F. Elliot, and R.I. Papendick. 1985. Soil microbial biomass and selected soil enzyme activities: effect of fertilization and cropping practices. Soil Biol. Biochem. 17:297-302. Bremner, J.M. 1965. Total Nitrogen. In C.A. Black (ed.) Methods of soil analysis, part 2. Agronomy 9:1149—1178. Amer. Soc. Agron., Madison, Wis. Brooks, P.D., B.B. McInteer, T. Preston, and M.K. Firestone. 1987. A diffusion method to prepare soil KCl extracts and kjeldahl digests for 15N analysis. Agronomy Abstracts. Nov 29—Dec 4. Atlanta, GA. Bruulsema, T.W. and R.B. Christie. 1987. Nitrogen contribution to succeeding corn from alfalfa and red clover. Agron. J. 79:96-100. Bundy, L.G. 1985. Corn fertilization. Univ. of Wisconsin Coop. Ext. Serv. Bull. A3340. Foth, H.D. 1962. Root and top growth of corn. Agron. J. 54:49-52. Fribough, H.A., and W.V. Bartholomew. 1956. Availability of nitrogen from crop residues during the first and second seasons after application. Soil. Sci. Soc. Am. Proc. 20:505-508. Hauck, R.D. 1971. Quantitative estimates of nitrogen cycle processes —- concepts and review. 1h Nitrogen-15 in soil and plant studies. IAEA (Vienna) 65-80. Heichel, G.H. 1987. Legumes as a source of nitrogen in conservation tillage systems. In The Role of Legumes in Conservation Tillage Systems. Soil Cons. Soc. Am., Ankeny, Iowa. pp. 29-35. 21 22 Hesterman, O.B., M.P. Russelle, C.C. Sheaffer, and G.H. Heichel. 1987. Nitrogen utilization from fertilizer and legume residues in legume-corn rotations. Agron. J. 79:726- 731. Jansson, S.L., and J. Persson. 1982. Mineralization and immobilization of soil Nitrogen. 1h F.J. Stevenson (ed.) Nitrogen in agricultural soils. Agronomy 22:229-252. Jenkinson, D.S., and D.S. Powlson. 1976. The effects of biocidal treatments on metabolism in soil I.Fumigation with chloroform. Soil Biol. Biochem. 8:167-177. Jokela, W.E., W.E. Fenster, C.J. Overdahl, C.A. Simkens, and J. Grava. 1981. Guide to computer programmed soil test recommendations for field crops in Minnesota. Minnesota Ext. Bull. 416. Jones, R.J. 1945. Nitrogen losses from Alabama soils in lysimeters as influenced by various systems of green manure crop management. J. Am. Soc. Agron. 34:574-585. Kitur, B.K., Smith, M.S., Blevins, R.L., and W.W. Frye. 1984. Fate of 15N-depleted ammonium nitrate applied to no- tillage and conventional-tillage corn. Agron. J. 76:240- 242. Lachat Chemicals, Inc. 10500 N. Port Washington Rd, Mequon, WI 53092. Lachat QuikChemT-M- Instructions Manual. Ladd, J.N. and M. Amato. 1986. The fate of nitrogen from legume and fertilizer sources in soils successively cropped with wheat under field conditions. Soil Biol. Biochem. 18:417-425. Ladd, J.N., M. Amato, R.B. Jackson, and J.H.A. Butler. 1983. Utilization by wheat crops of nitrogen from legume residues decomposing in the field. Soil Biol. Biochem. 15:231-238. Ladd, J.N., J.M. Oades, and M. Amato. 1981. Distribution and recovery of nitrogen from legume residues decomposing in soils sown to wheat in the field. Soil Biol. Biochem. 13:251-256. Moore, A.W. 1974. Availability to rhodesgrass (Chloris gayana) of nitrogen in tops and roots added to soil. Soil Biol. Biochem. 6:249-255. 23 Norman, A.G., and G.H. Werkman. 1943. The use of the nitrogen isotope 15N in determining nitrogen recovery from plant material decomposing in soil. J. Am. Soc. Agron. 35:1023-1025. ~ Parr, J.F., and R.I. Papendick. 1978. Factors effecting the decomposition of crop residues by microorganisms. 1h W.R. Oschwald (ed.) Crop Residue Management Systems, pp. 109- 209. American Society of Agronomy Special Publication No. 31, Madison, Wisconsin. Power, J.F., J.W. Doran, and W.W. Wilhelm. 1986. Uptake of nitrogen from soil, fertilizer, and crop residues by no- till corn and soybean. Soil Sci. Soc. Am. J. 50:137-142. Preston, T. and N J.P. Olsen. 1983. Interfacing an automatic elemental analyzer with an isotope-ratio mass— spectrometer: the potential for fully automated total nitrogen and 15N analysis. Analyst. 108:971-977. Russelle, M.P., O.B. Hesterman, C.C. Sheaffer, and G.H. Heichel. 1987. Estimating N and ”rotation” effects in legume-corn rotations. 1h The Role of Legumes in Conservation Tillage Systems. Soil Cons. Soc. Am., Ankeny, Iowa. pp. 41-42. - Schnurer, J., M. Clarholm, and T. Rosswall. 1985. Microbial biomass and activity in an agricultural soil with different organic matter contents. Soil Biol. Biochem. 17:611-618. Stanford, G. 1973. Rationale for optimum nitrogen fertilization in corn production. J. Environ. Qual. 2:159- 166. Stickler, F.C., W.D. Shrader, and I.J. Johnson. 1959. Comparitive value of legume and fertilizer nitrogen for corn production. Agron. J. 51:157—160. Vallis, I. 1983. Uptake by grass and transfer to soil of nitrogen from 15N-labelled legume materials applied to a rhodes grass pasture. Aust. J. Agric. Res. 34:367-376. Voss, R.D., and W.D. Shrader. 1979. Crop rotations: Effect on yields and response to nitrogen. Iowa State Univ. Coop. Ext. Serv. Pm-905. , and . 1984. Rotation effects and legume sources of nitrogen for corn. p.61-68. In D.A. Bezdicek et al. (ed.) Organic farming : Current technology and its role in sustainable agrigulture. Spec. Pub. 46. American Society Agronomy, Madison, WI. 24 Warncke, D.D., D.R. Christenson, and M.L. Vitosh. 1985. Fertilizer recommendations: Vegetable and field crops in Michigan. Michigan State Univ. Coop. Ext. Serv. Bull. E- 550. Yaacob, 0., and G.J. Blair. 1980. Mineralization of 15N- labelled legume residues in soils with different nitrogen contents and its uptake by rhodesgrass. Plant Soil 57:237- 248. 25 Table 1. Soil characteristics and clilatalogical data for East Lansing (8L) and Kellogg Biological Station (fi). Soil(0-15 ca) f Precipitation lean Air Tenperature lav-Sept * Long-tern § lay-Septi Long-tern§ Location pB CIC 0! l 1986 average 1986 average (re/100g) --- g/kg --- --------- II ------------------- 00 --------- IL 1.2 15 28 2.0 630 366 18.0 18.4 KBS 8.9 11 16 1.0 718 195 19.1 19.2 'tSanpled Oct 1985 :tData recorded at lational Heather Service Stations at lichigan State University, East Lansing and Kellogg Biological Station, Hickory Corners, II. §Long tern averages coapiled fron official weather station at Lansing, II Iational Heather Service Office and lational Weather Service Clinatological Station, Kellogg Biological Station, Hickory Corners, II. 26 Table 2. Recovery of alfalfa-15! by corn and in soil at BL. Ball Spring Shoots Boots/crowns Shoots Boots/crowns lean 07 ------- Recovery of alfalfa-15! (2 of input) -------- Corn Grain 9.5 7.7 13.5 9.6 10.1 36 Stover 5.2 1.1 9.3 5.1 6.1 22 Boots 0.11 0.10 0.60 0.17 0.5 21 Total(Corn) 15.1 12.5 23.1 15.5 16.7 26 Soil Inorganic 1.11 1.23 2.00 1.57 1.5 17 Organic 39.2 37.8 57.6 50.7 16.3 18 Iicrohial Bio-ass 8.1 7.7 11.1 8.3 8.9 11 Total(SoiI) 10.6 38.3 59.8 52.2 17.8 17 Total (Corn * Soil) 55.7 51.3 83.0 67.7 61.1 11 27 Table 3. Recovery of alfalfa-15l by corn and in soil at KBS. [all Spring Shoots Roots/crowns Shoots Roots/crovns Bean 07 ------- Recovery of alfalfa-15! (: of input) -------- Corn Grain 15.1 18.2 19.2 11.1 15.9 13 Stover 10.8 6.1 10.1 6.3 8.3 12 Roots 1.00 0.15 0.87 0.72 0.8 27 TotalCorn) 26.9 21.7 30.2 18.1 25.0 28 Soil Inorganic 2.59 2.31 2.15 2.53 2.5 30 Organic 12.5 36.1 16.1 38.1 10.8 11 licrohial Bio-ass 6.7 6.1 7.7 6.1 6.7 21 TotaI(Soil) 15.1 38.7 18.5 11.0 13.3 10 Total (Corn 9 Soil) 72.0 63.1 78.7 59.1 68.3 11 28 TIBLR 1 : Rifect of plant part and tine of incorporation on corn dry latter yield and total I uptake at RL and KBS. Grain Stover Root OraintStover+Root U.l. Total I U.l. Total I U.l. Total I U.l. Total N Yield Uptake Yield Uptake Yield Uptake Yield Uptake ------------------------------------ (g/plot) ---------------------------------- ................ - --- BL --------------------------------__-_- Plant part Shoot 231 3.2 221 2 0 32.2 0.18 190 5.1 Root/crovn 253 3.1 205 1 8 29.0 0.17 188 5.1 Tine of incorporation tall 271 3.5 238 2.0 35.8 0.20 512' 5.7 Spring 218 3.1 191 1.9 26.1 0.16 138 5.1 lean 213 3.3 215 1.9 31.1 0.18 189 5.1 CY 23 21 11 19 20 25 12 18 ....................................... (BS -------------------------------------- Plant part Shoot 263 3.6 222 2.0 21.9 0.21 510 5.8 Root/cronn 210 3.2 206 1.9 22.1 0.18 169 5.2 Tine of incorporation [all 257 3.1 218 2.0 23.6 0.19 198 5.6 Spring 217 3.1 211 1.8 23.1 0.20 182 5.1 lean 252 3.1 211 1.9 23.5 0.19 190 5.5 07 20 21 ll 20 20 23 15 18 ‘ 8 value significant at 0.05 level of probability (Tall > Spring) 29 Table 5. I nineraliaation potential and percent nineraliaed l derived tron alfalfa for fresh soil sanpled iron the 0-15 on later after corn harvest at IL and KBS. Tall Spring Location Shoots Roots/crovns Shoots Roots/cronns lean CY --------- I nineraliaation potential (ug/g) --------- IL 10.8 10.8 11.1 10.1 10.8 10 186 ~ 15.1 13.7 11.3 11.8 11.1 13 --- Percent nineralired I derived fron alfalfa (1) --- BL 6.9 8.8 5.1 6.7 6.9 8 IRS 9.0 11.9 18.9 13.1 10.7 30 30 Table 6. Percent I in corn (grain + stover + roots) derived iron alfalfa at IL and IRS. Fall Spring Location Shoots Roots/craves Shoots Roots/crowns lean .07 ----- Percent l in corn derived fron alfalfa (2) ---- RL 8.5 7.2 11.7 9.8 10.0 13 [US 11.6 15.1 16.9 11.1 11.6 22 31 TABLR 7. Recovery of alfalfa-151 (1 of input) in total, inorganic, organic, and nicrobial bionass soil l by depth at 8L and KBS. Location 8L KBS -- Recovery of alfalfa 15! (X of input) I-- Total Soil 5 0-15 37.3 33.6 15-30 8.2 7.2 30-15 1.3 1.1 15-60 1.1 1.1 Inorganic Soil l 0-15 1.07 1.85 15-30 0.35 0.57 30-15 0.08 0.13 15-80 0.07 0.11 Organic Soil 0 0-15 36.2 31.9 15-30 7.9 8.6 30-15 1.2 1.3 15-60 1.0 1.0 'ilaiues are averaged over both plant parts (shoot and root/crovn) and tines of incorporation (fall and spring) 32 Table 8. Dry latter yield, 1 content, total I uptake, percent I derived fron alfalfa and recovery of alfalfa-151 by barley (grain + stover (strap) + roots) groan in 1987 after corn at 6L and (BS. Location IL KBS Dry latter yield (g/plot) 96 13 I content (lg/g) 9.8 16 Total I uptake (g/plot) 0.95 0.69 Percent I derived fron alfalfa (X) 1.0 5.6 Recovery of alfalfa-151 (t of input) 1.15 1.18 APPENDICES APPENDIX A APPENDIX A Recovery of alfalfa-15N -- Data and Calculations 1. Tables A1 and A2 Total N uptake by grain, stover and root components of corn, Variables (V) 11, 12, and 13, respectively, were calculated by multiplying the d.m. yield of the component times the N content (%N). For example: V11 = V5 x V8/100. V14 2 V11 + V12 + V13 V15=V5+V6+V7 V16 = V14 / (V15/100) 2. Tables A3 and A4 Recovery of alfalfa-15N by each corn component (V14, V15, V16) was calculated by multiplying the d.m. yield of the component times the N content (%N) times the 15N atom % excess, divided by the amount of alfalfa-N applied times the 1‘5N atom % excess of the alfalfa. For example: If V3 = 1 Then V14 = (V5 x V8/100 x V11) / 0.263292 Else V14 = (V5 x V8/100 x V11) / 0.2256. Where: 0.2632 3.2592 x 8.0746/100 0.2256 3.2592 x 6.9220/100 33 34 Note: 3.2592 2 g of N applied to 60 cm dia. microplots (equivalent to 112 kg N ha-l) 8.0746 = 15N atom % excess of alfalfa shoots 6.9220 = 15N atom % excess of alfalfa root/crowns V17 : V14 + V15 + V16 3. Tables A5 and A6 %N in each corn component derived from alfalfa was calculated by dividing the 15N atom % excess of the component by the atom % excess of alfalfa times 100. For example: If V3 = 1 Then V12 = V9/8.0746 x 100 'Else V12 2 V9/6.9920 x 100. V15 = {[(V12/100 x V5) + (V13/100 x V6) + (V14/100 x V7)] / V8} x 100 4. Tables A7 and A8 Recovery of alfalfa-15N in the total N fraction of each soil layer was calculated by the same principle as recovery by corn components. For example: If V3 = 1 Then V17 : (V5 x V9/100 x V13) / 0.2632 Else V17 2 (V5 x V9/100 x V13)/ 0.2256. V21 = V17 + V18 + V19 + V20 35 5. Tables A9 and A10 Recovery of alfalfa-15N in the inorganic N fraction of each soil layer was calculated by the same principle as recovery by corn and total soil N. For example: If V3 : 1 Then V17 : (V5 x V9 x V13) / 263200 Else V17 : (V5 x V9 x V13) / 225600. V21 : V17 + V18 + V19 + V20 Note: Recovery of alfalfa-15N in the organic fraction of each soil layer was calculated by subtraction: Values from Tables A9 and A10 (Inorganic N) subtracted from corresponding values from Tables A7 and A8 (Total N) 6. Tables A11 and A12 Microbial biomass C was calculated by Cf/0.41 as explained in the Materials and Methods section. 010 and C20 (V6 and V7) are provided for recalculation by different methods if desired. 7. Tables A13 and A14 Equations for calculating Kn and microbial biomass N appear with the variable descriptions and were also explained in the Materials and Methods section. Recovery of alfalfa-15N in the microbial biomass was calculated by multiplying the 0-15 soil layer d.w. times microbial biomass N times 15N atom % excess of inorganic N from the fumigated sample, divided by the amount of alfalfa N 36 applied times the atom % excess of the alfalfa. For example: If V3=1 Then V17 = V5 x V15 x V16 / 263200 Else V17 : V5 x V15 x V16 / 225600. 8. Table A15 1‘5N atom % values for total N and inorganic N from the 60-75 cm soil layer for each microplot at EL and KBS appear in cases 1-16. Six samples from the 60-75 cm soil layer located adjacent to the microplots were analyzed for backround 15N levels in the total N fraction and appear in cases 18-23. Means from V2 and V4/cases 1-16 were compared to the mean from V2/cases 18-23 by a paired t test and found to be significantly different at the 0.05 level of probability. Likewise, means from V3 and V5/cases 1-16 were compared to the mean of V3/cases 18-23 and found to be significantly different at the 0.05 level of probability using a paired t test. In both cases, mean values from cases 1-16 were higher than means from cases 18-23. 9. Table A16 N mineralization capacity was calculated by multiplying the amount of N mineralized during a 20-day aerobic incubation times the volume of KCl used in extract divided by the dry weight of soil used. For example: V8 = (V7 - V6) * 100/20 37 where 100 = ml of 2M KCl and 20 = dry weight of soil. Note: NH1 was not present in KCl extract from either time zero or 20—day samples. Percent mineralized N derived from alfalfa was calculated by dividing 15N atom % excess of 20- day KCl extracted N03 by 15N atom % excess of alfalfa. For example: If V4 2 1 Then V10 = V9/8.0746 x 100 Else V10 : V9/6.9920 x 100. 10. Tables A17 and A18 Percent N derived from alfalfa and total N uptake for barley was calculated in the same manner as for corn. For examples: If V4 : 1 Then V14 = V11/8.0746 x 100 Else V14 = V11/6.9920 x 100, and V17 : V5 x (VS/100). V21=V5+V6+V7 V22 : V20 / (V21/100) V23 = {[(V14/100 x V17) + (V15/100 x V18) + (V16/100 x V19)] / V20} x 100 11. Tables A19 and A20 Recovery of alfalfa-15N by barley was calculated in the same manner as recovery by corn. For example: If V3 = 1 Then V17 = (V5 x V8/100 x V11) / 0.263292 Else V17 = (V5 x V8/100 x V11) / 0.2256. V20 = V17 + V18 + V19 313 Table 11. Corn dry natter yield, I content, and total I uptake at 8L. LIST OF YIRIIBLIS YIR p—n emmflmmfiuwu— TYPI nuneric nuneric nuneric nuneric nuneric nuneric nuneric nuneric nuneric nuneric nuneric nuneric nuneric nuneric nuneric nuneric lIlI/UISCRIPTIOI Plot 1 Replication Plant Part 1=Sboot 2=Root/crovn Tine of Incorporation 1=Yall 2=Spring Grain R.I. Yield (g/plot) Stover 0.l. Yield (g/plot) Root R.I. Yield (g/plot) XI Grain II Stover SI Root Total I Uptake by Grain (g/plot) Total I Uptake by Stover (g/plot) Total I Uptake by Roots (g/plot) Total I Uptake by Corn - Grain+Stover+Roots (g/plot) Corn - Urain+Stoveriioots 0.l. Yield (g/plot) Corn - Grain+StoveriRoots II 3 1 5 6 7 8 9 10 11 12 13 11 15 2 1 261.6 203.5 27.5 1.19 0.80 0.52 3.11 1.62 0.11 1.91 195.6 1 1 191.0 222.8 27.5 1.27 0.73 0.53 2.16 1.61 0.15 1.21 111.3 2 2 287.9 182.3 19.7 1.15 0.97 0.57 1.18 1.77 0.11 8.07 189.9 1 2 117.3 233.2 36.2 1.57 0.81 0.51 1.81 1.96 0.20 1.00 386.7 2 2 221.9 172.7 19.1 1.30 0.76 0.19 2.89 1.31 0.09 1.30 111.0 1 2 281.1 199.0 27.6 1.11 0.78 0.55 1.10 1.51 0.15 5.79 510.7 1 1 251.1 215.5 39.2 1.15 0.72 0.51 3.68 1.76 0.20 5.61 539.1 2 1 332.7 261.7 18.6 1.32 0.80 0.53 1.39 2.09 0.21 6.72 611.0 1 1 338.1 235.8 38.3 1.21 0.78 0.55 1.19 1.83 0.21 6.23 612.2 1 2 188.7 211.7 29.2 1.11 0.96 0.59 2.63 2.03 0.17 1.83 127.6 2 1 283.1 256.3 36.2 1.23 0.71 0.17 3.18 1.90 0.17 5.51 575.9 2 2 221.5 202.1 32.0 1.17 1.08 0.70 3.25 2.20 0.22 5.67 155.9 2 2 180.9 168.3 22.1 1.36 1.01 0.77 2.15 1.68 0.17 1.30 369.3 2 1 232.5.198.3 36.0 1.10 1.11 0.63 3.21 2.27 0.23 5.71 166.8 1 2 227.9 183.2 21.7 1.17 1.33 0.57 3.36 2.11 0.11 5.91 135.8 1 1 266.1 262.1 31.9 1.36 1.19 0.68 3.63 3.11 0.21 6.98 563.1 NMNHNGD~°°=~°°N¢OCD 353 Table 12. Corn dry latter yield, l content, and total I uptake at KBS. LIST 0! YIRIIULIS ) t o l p l ‘ Ila.) t 80 no... 0/ I: no" "a .. ed nu v.uu p I “.1 s It‘lS'l u: 5.00555: '2 010‘ e o lploll .11 plus: .u 01 Ina/DID II \II ‘(SG ti)... ’1 (.1 55 03.050) t .tt 0101’. nos 00 R 1’0 i'tnoo :‘p/l aha-Ill 20,100.. r 001.4. out“, GSIcr-l tt‘ 8 five a d5 '0"'" . rdl bbbbou 0 ”1 ed 5.. I s 0.11 800888 " Ivai'lo kit-DIR..- I n 0 .Y #5 55.1.3. 3 0...“ .l ppppaa 6 irIl . . r uunurr s ta onlne 66 ! “Poor-D .i't'l'l N‘ o rnawo .- ebnsh hue-ark. hilllflh s mnwumnuml mmmmmn cccccccccccccccc iiieliiieliiolielie‘ae‘o Irrtrrrrrrrrrtrrr nmmmmnmmmunummnum a nun nu rlnnlnlnnllnnnunn ‘123‘567890123456 A 1111111 ' 015! I0. 15 16 11 5 l 2 3 1 29415008426619.1088 611814160411965‘. oooooooooooooooo 3422322253‘33233 5498131211168‘16 1886198099811668. 00000001000000.005 9519310845114028 0910998808111889 9.5001000010010000. 6462182539113097 251222225335423‘. 11111111111115.5111 94800586084628.1J5 33333331961511uoefllu. 3233221212212122 1117312631818113 6442985050580929 2222111222212121 3193009306014351 443 Table 13. Recovery of alfalfa I-15 by corn at 11. LIST OT YIRIIBLIS YIR anemone-mess.— TYPR nuneric nuneric nuneric nuneric nuneric nuneric nuneric nuneric nuneric luneric nuneric nuneric nuneric nuneric nuneric nuneric nuneric IllR/URSCRIPTIOI Plot 1 Replication Plant Part 1=Sboot 2=Rootlcrovn Tine of Incorporation 1=Yall 2=Spring Grain 0.8. Yield (g/plot) Stover O.B. Yield (g/plot) Root 0.I. Yield (g/plot) 2| Grain XI Stover XI Root I-15 Iton 8 Ixcess Grain I-15 Iton X lxcess Stover I-15 Iton 2 [races Root Recovery of alfalfa I-15 by Grain (X of input) Recovery of alfalfa I-15 by Stover (I of input) Recovery of alfalfa I-15 by Boots (1 of input) Recovery by Corn - 6rain+Stovethoots (t of input) a» .‘1 0‘ as ‘3 co ‘9 p. o 11 12 13 .5011 0.5591 0.1771 7.02 .5077 0.5115 0.5361 1. 71 .7332 0.7888 0.7690 13.59 .0228 1.2139 0.9257 7.15 .6153 0.6731 0 7359 8.28 .1710 1.1005 0. 9296 18. 28 .8103 0.7018 0.6173 11.76 .1579 0.1188 0.1351 8. 90 .8167 0.8822 0.8888 13.18 .1850 1.2100 0.9078 11.81 .1802 0. 5085 0.1286 7.10 .8168 0.6711 0.8911 9. 32 .6680 0.6192 0.6687 7.27 .5326 0.5172 0.1813 7. 66 ”NpNNp—No—or‘O-ONNNN—OI-fi NNN—NNe—ouuNNNr—Nu—ON annuawumuumowpanmo m-cht—uGOGN-bubwd-iabfi fiOWGM-‘Qo—fl‘e—GQQGOO N—pp—NNNNNN—r—Nr-ONN mamaeumum-w~nuu~e MuoaNa—mumonuwnu O O O O l I O O O O O I O O O I v—Nuua-wflcoflmadnucom “housemates“-uNp-ou—anm -panmamaaoquam—dd C O O O O O O I I I I O O D O I «ado—oweoucawoapm-dmm Ov—oOOOO—gcQI—ca—IGOP .5782 0.6089 0.5235 7.97 .3178 1.3012 1.0582 18.81 1. «pmgmpcwppmumou- ~°NmmNm°—fl-°°I—.~° mwcumamemommumamp 15.61 4:1 Table 11. Recovery of alfalfa l-15 by corn at KBS. LIST 0! YIRYIBLIS YIR ou-«anmpwwu—e TYPR auneric nuneric nuneric nuneric nuneric nuneric nuneric nuneric nuneric nuneric nuneric nuneric nuneric nuneric nuneric nuneric nuneric ’ llll/OISCRYPTIOI Plot 8 Replication Plant Part 1=Sboot 2=Root/crovn Tine of Incorporation 1=Pall 2=Spring Grain 0.I. Yield (g/plot) Stover 0.l. Yield (g/plot) Root 0.8. Yield (g/plot) XI Grain ZI Stover II Root l-15 lton X Rxcess Grain I-15 Iton 2 Excess Stover I-15 Iton 1 Excess Root Recovery of alfalfa I-15 by Grain (I of input) Recovery of alfalfa I-15 by Stover (I of input) Recovery of alfalfa I-15 by Boots (1 of input) Recovery by Corn - Grain*Stover+Roots (X of input) .5137 1.2698 1.1301 20. 83 .0819 0.9810 0.9189 13.19 .9111 0.7768 0.6913 11.35 .1891 0.1921 0.5152 6. 73 .9521 0.9651 0.8655 8. 67 .3066 0.5758 0.5958 12. 82 .2273 1.1717 1.1113 12.33 .3068 0.6172 0.5808 29.05 .2526 1.5501 1.2951 18.18 .5519 0.9329 0.9239 7. 65 .9532 0.8021 0.9915 16. 85 .7021 0.7503 0.7297 19.82 u—nNa—oNNv—hNo-or-AO—ONNr—oNNr—s NNNNe—nuNwNn—hr-bNNNO-IN wmmdompmmdumuuu—o daemon—ancofls—uco-a-aocemco O O O C O I I C O O O O O O I O Hmugdoaoumeoumu—u r-oNr—Ne—hNNNNa—na-n—aNNNN ‘DNGDOOMOO‘O‘BQ‘DN--.’ udmmda-fllumwfiufln—or—m °°°°°°°°°°°G°°°° NN—N—‘NNHNr—Nwwwmw mcdpmqanmpuuuuuuu I O O O O O I I l O O O I I O O upmmmpucmmmocmhm p—p—np—Ap‘p-ar-‘y—p—p-p—nmp—oflg—g—op—n -uNfimuumNNNNNn—OMN woeuapoumwmpnafia ch—t—bceg—Hh—r—FGGPr-og—sr—I .5637 1.3603 1.0660 7.15 .6037 1.3710 1.1888 29.20 .1016 1. 6596 L 3159 19. 91 .8618 1.6061 1. 3313 22. 61 1. 25. 30 31. 72 17.98 412 Table 15. Percent corn I derived fron alfalfa at KL. LIST 08 YARIA8LIS TAR TTPI lAlU/DISURIPTIUI 1 auneric Plot 1 2 ruleric Replication 3 nuleric Plant Part 1=Sboot 2=Root 1 Inneric Tine of Incorporation 5 nuneric Total I Uptake by Grain (g/plot) 6 nuaeric Total I Uptake by Stover (g/plot) 7 nuleric Total I Uptake by Roots (g/plot) 8 nuneric Total I Uptake by Corn - Grain+3tover+Roots (g/plot) 9 nuleric l-15 Aton 3 laces: Grain 10 nuneric I-15 Aton 1 Trees: Stover 11 nuneric I-l5 Aton X lxcess Root 12 nuneric II in Grain Derived frol Alfalfa 13 nuneric 30 in Stover Derived fron Alfalfa 11 nuneric II in Roots Derived fron Alfalfa 15 nuneric II in Corn - Urain+Stover+Roots Derived frol Alfalfa UASR ( IO. 1 2 3 1 5 6 7 8 9 10 11 12 13 11 15 1 101 1 2 1 3.11 1.62 0.11 1. 91 0. 50110 0.55910 0.17710 7. 28 8.08 6. 89 7. 52 2 102 1 l 1 2.18 1.81 0.15 1. 21 0.50770 0.51150 0.53610 8. 29 6. 33 6. 81 6. 33 3 103 1 2 2 1.18 1.77 0.11 8.07 0.73320 0.78880 0.76900 10. 59 1L 10 11.11 10. 82 1 101 1 1 2 1.81 1.96 0.20 1. 00 L 02280 1. 21390 0.92570 12.86 15.03 11.16 13.77 5 201 2 2 Z 2.89 1.31 0.09 1. 30 0.81530 0.67310 0. 73590 9. 32 9. 72 10. 63 9.15 6 202 2 1 2 1.10 1.51 0.15 5. 79 1.17100 L 10050 0.92960 11.51 13.63 11.51 11.22 7 203 2 1 1 3.68 1.76 0.20 5. 81 0.81030 0.70160 0.61730 10.11 8. 73 7. 81 9. 78 8 201 2 2 1 1.39 2.09 0.21 8. 72 0.15790 L 11880 0.13510 6. 62 6.18 6.29 6. 56 9 301 3 1 1 1.19 1.83 0.21 8. 23 0. 81870 0.88220 0.86880 10.19 10. 68 8. 28 10.17 10 302 3 1 2 2.63 2.03 0.17 1. 83 1.18500 1. 21000 0.90780 11.68 15.38 11.21 11.81 11 303 3 2 1 3.18 1.90 0.17 5. 51 0.18020 0.50850 L 12860 6. 91 7. 35 6.19 7.07 12 301 3 2 2 3.25 2.20 0.22 5. 87 0.61680 0.87110 0.69110 9. 31 9. 71 9. 99 9. 52 13 101 1 2 2 2.15 1.68 0.17 1. 30 0.66800 0. 81920 0.68870 9. 85 9. 38 9. 68 9.51 11 102 1 2 l 3.21 2.27 0.23 5. 71 0. 53280 0.51720 0.18130 7. 69 7.17 7.00 7. 58 15 103 1 1 2 3.36 2.11 0.11 5. 91 1. 31780 1.30120 1. 05820 18.32 16.11 13.11 1L 18 18 101 1 1 1 3.63 3.11 0.21 8. 98 0. 57820 0.80890 0.52350 7.18 7. 51 6.18 7. 31 4&3 Table A8. Percent corn I derived fron alfalfa at [88. LIST 0! 718118088 YAR TYPE IAlE/DESURIPTIDI 1 nuneric Plot 1 2 nuneric Replication 3 naneric Plant Part 1=Sboot 2=Root 1 nuneric Tine of Incorporation 5 nuneric Total I Uptake by Grain (g/plot) 8 auneric Total I Uptake by Stover (g/plot) 7 nuneric Total I Uptake by Roots (g/plot) 8 nuneric Total I Uptake by Corn - 8rain+8tover+loots (g/plot) 9 nuneric I-15 1ton 2 Excess Grain 10 nuneric I-15 Aton 2 Excess Stover 11 nuneric I-15 1ton 1 Excess Root 12 nuneric II in Grain Derived fron Alfalfa 13 nuneric XI in Stover Derived fron Alfalfa 11 nuneric II in Roots Derived fron Alfalfa 15 nuneric 2| in Corn - 8rain+8tover+Roots Derived fron Alfalfa 8188 I0. 1 2 3 1 5 6 7 8 9 10 11 12 13 11 15 l 101 1 1 1 3.62 2.88 0.25 8. 73 1. 51370 1. 28980 1.13010 18.75 15.73 11.00 17.29 2 102 l 1 2 1.79 2.29 0.20 7. 28 1. 60370 1. 37100 1.16880 19.88 17. 02 1L 15 18.82 3 103 1 2 2 2.71 1.71 0.30 1. 75 1. 08190 0. 98100 0. 91890 15.87 11.17 13.28 IL 98 1 101 1 2 1 2.81 2.17 0.22 5. 51 0. 91110 L 77880 0.69130 13.16 11.22 9. 99 12.11 5 201 2 2 2 3.10 1.79 0.18 5. 07 0.18910 0.19210 0.51520 7.07 7.11 7. 88 7.11 6 202 2 1 2 2.10 1.81 0.22 L 13 0.95210 0.98510 0.86550 11.80 11.98 10. 72 11.81 7 203 2 2 1 2.18 1.21 0.11 3. 50 1. 30660 0. 57580 L 59560 18.88 8. 32 8. 60 11.90 8 201 2 1 1 2.81 1.82 0.22 1. 88 1. 22730 1.17170 1.11130 15.20 11.55 11.13 11.90 9 301 3 2 1 5.02 2.83 0.18 7. 83 1. 30660 0.61720 0.58080 18.88 9. 35 8. 39 15.11 10 302 3 1 2 3.16 1.78 0.25 5.16 1. 25260 1. 55010 1. 29510 15.51 19.20 16.01 18.75 11 303 3 1 l 1.78 1.82 0.22 L 80 1.10160 1. 85980 L 31590 13.81 20. 55 18.67 15.59 12 301 3 2 2 3.11 2.07 0.12 5.30 L 55190 0.93290 0.92390 8. 02 13.18 13.35 10. 27 13 101 1 2 2 3.99 1.51 0.17 5. 69 0.95320 0.80210 0. 99150 13.77 11.59 11.37 13.22 11 102 1 2 1 2.83 1.51 0.11 1. 28 1. 70210 0. 75030 0.72970 21. 59 10. 81 10. 51 19.28 15 103 1 1 2 3.58 1.87 0.13 5. 58 1. 86180 1. 60810 1. 33130 20. 62 19.89 18.52 20. 28 18 101 1 1 1 3.18 1.89 0.19 5. 58 0.58370 1. 38030 1.06600 6. 98 18.85 13.20 10. 55 441 Table 17. Recovery of alfalfa I-15 in total soil I at EL. YAR DESCRIPTIDI 71R 1 Plot 1 2 3 Plant part lzsboots 2=root/croln 1 5 0-15 Total Layer 0.8. (g) 6 7 30-15 Total Layer 0.8. (8) 8 9 0-15 Total I (II) 10 11 30-15 Total I (II) 12 13 0-15 Total I 8-15 Aton I Excess 11 15 30-15 Total I I-15 Aton I Excess 16 17 Recovery of alfalfa I-15 in 0-15 (I of input) 18 19 Recovery of alfalfa I-15 in 30-15 (I of input) 20 21 Recovery of Alfalfa l-l5 in 0-80 (I of input) CASE IO. 1 2 3 1 5 8 7 8 9 10 11 l 101 1 2 1 16812 51787 66038 51538 0. 20 0.18 0.05 0. 03 2 102 1 1 1 15785 13881 38389 18825 0. 20 0.15 0.07 0. 01 3 103 1 2 2 18328 53152 56151 19315 0. 21 0.17 0.08 0. 03 1 101 1 1 2 19356 17106 58815 18291 0. 23 0.17 0.01 0. 05 5 201 2 2 2 51092 19103 72985 82351 0.19 0.11 0.03 0. 03 8 202 2 1 2 15190 18717 53397 82821 0. 21 0.18 0.05 0. 01 7 203 2 1 1 17601 57120 67889 83010 0. 20 U. 18 0.01 0. 03 8 201 2 2 1 15871 15693 61757 82619 0. 20 0.16 0.01 0. 03 9 301 3 1 1 15858 53631 68827 57715 0.18 0.11 0.01 0. 03 10 302 3 1 2 13195 17517 81892 59852 0.19 0.13 0.05 0. 03 11 303 3 2 1 17086 13621 19991 11275 0.18 0.12 0.03 0. 03 12 301 3 2 2 11281 50980 78858 61951 0.19 0.11 0.03 0. 03 13 101 1 2 2 15301 11558 53789 59831 0. 23 0.16 0.06 0. 03 11 102 1 2 1 13915 12780 81115 55558 0. 21 0.15 0.01 0. 03 15 103 1 l 2 53831 51113 71352 69022 0. 20 0.11 0.03 0. 03 16 101 1 1 1 16097 51206 58611 67017 0.19 0.11 0.07 0. 03 1 31.02 7.01 1.11 0.19 39.63 2 35.87 3.65 0.81 0.92 11.05 3 35.77 9.18 0.71 0.86 18.35 1 56.38 11.70 1.01 0.73 72.79 5 33.11 1.78 0.56 0.98 39.78 6 35.31 13.80 1.18 1.22 51.52 7 33.15 5.66 0.85 0.89 10.51 8 30.98 8.05 0.75 0.93 10.72 9 27.31 8.55 1.59 0.92 38.37 10 10.15 9.31 1.51 1.18 52.75 11 28. 76 1.02 0.81 0.33 33.91 12 39. 31 7.17 1.56 0.78 19.15 13 57. 99 11.90 1.28 2.59 73.78 11 30.96 7.99 1.00 1.08 11.01 15 19.19 9.01 1.21 1.91 81.38 18 30.73 8.25 1.81 0.98 11.57 DESCRIPTIUI Replication Tine of incorporation lzfall 2=spring 15-30 Total Layer 0.8. 15-80 Total Layer 0.8. 15-30 Total I (II) 15-60 Total I (II) 15-30 Total I I-15 Aton I Ixcess 15-60 Total I I-15 Aton I Excess Recovery of alfalfa I-15 in 15-30 (I of input) Recovery of alfalfa 8-15 in 15-60 (I of input) .07512 0.01887 0.00780 0.00850 .10301 0.01121 0.00589 0.01373 .08111 0.02322 0.00513 0.00911 .12918 0.01707 0. 01037 0.00825 .07862 0.02011 0.00198 0.01055 .09710 0.01112 0.01158 0.01369 .09280 0.01112 0.00807 0.01178 .07798 0.02188 0.00612 0.01223 .08682 0. 02386 0.01399 0.01298 .13098 0.03810 0.01178 0.02335 .07775 0. 01871 0.01101 0.00635 .10622 0.02118 0.01377 0.00972 .12898 0.01006 0.00810 0.02830 .07710 0.02885 0.00911 0.01510 .12191 0.03071 0.01689 0.02613 .09319 0.03012 0.03000 0.01317 °°°°°°°°°°°°°°°° 415 Table 18. Recovery of alfalfa I-15 in total soil I at [88. TAR DISCRIPTIOI 1 Plot 1 2 Plant Part 1=Sboot 2=Rootlcrovn 5 0-15 Total Layer 0.8. (g) 7 30-15 Total Layer 0.8. (g) 9 0-15 Total I (II) 11 30-15 Total I (II) 13 0-15 Total I I-15 Aton I Excess 15 30-15 Total I I-15 Aton I Ixcess 11 Recovery of alfalfa I-15 in 0-15 (I of input) 718 DESCRIPTIUI 2 Replication 1 Tine of Incorporation 1=Iall 2=Spring 6 15-30 Total Layer 0.8. (g) 8 15-80 Total Layer 0.I. (g) 10 15-30 Total I (II) 12 15-80 Total I (II) 11 15-30 Total I I-15 Aton I Ixcess 16 15-80 Total I I-15 Aton I Ixcess 18 Recovery of alfalfa I-15 in 15-30 (I of input) 19 Recovery of alfalfa I-15 in 30-15 (I of input) 20 Recovery of Alfalfa I-15 in 15-60 (I of input) 21 Recovery of Alfalfa I-15 in 0-60 (I of input) 8168 I0. 1 1 5 6 7 N u 8 9 1 50276 61188 55109 62233 2 56987 51327 19111 11270 2 57288 52598 52120 80357 101 0. 0. 0. 1 17399 15185 55818 58071 0. 0. 0. 0. 0. 102 103 101 201 202 203 201 301 302 303 301 101 102 103 101 2 55886 53883 60028 81888 2 80739 61928 88310 81808 1 51809 51178 58313 61359 1 50031 65865 62392 11739 1 17521 58753 57151 80371 0. 2 59931 58883 58982 59267 0. 1 50811 16820 52111 18086 0. 2 82531 52810 53558 17855 0. 2 51202 77810 82198 58382 0. 0. 0. 0. meadow-pun:— 1 52318 87365 88797 59081 2 51921 51383 82812 88538 1 19868 55906 80811 83727 -ubehubwuwwNNNNr—e—o—e—a F-‘l—ONNNI—fih-ONHNMNNNHI—h .18235 0.06208 0.03273 0.03238 3 .17099 0.01793 0.01598 0.03079 3 .15812 0. 01077 0.01859 0.02201 3 .13811 0.07572 0.01109 0.02989 2 .11190 0.02818 0. 02555 0.02186 2 .15976 0.01575 0.02191 0.02075 3 .13011 0.05322 0. 03038 0. 07955 2 .20906 0.07553 0. 01318 0.01892 3 .11539 0. 01975 0.01115 0.01810 2 .22219 0.03790 0. 02985 0.03351 1 .19818 0.01825 0.03652 0.03817 3 .11207 0.03828 0.01831 0.01808 3 .13016 0 03072 0.02173 0. 01690 3 .11163 0.01210 0.02123 0.02503 3 .20791 0.07158 0.01388 0. 05139 3 .20072 0.07178 0.01531 0.03111 3 19 1 31.99 11.18 1. 2 35.52 5.71 3 37.01 5.13 1 25.68 9.10 5 29.98 3.92 8 37.87 7.51 7 28.11 8.90 8 31.13 9.13 9 20.98 10.11 15.11 1.71 31.91 5.26 33.82 8.21 31.93 6.59 37.50 7.38 39.80 7.05 31.71 7.89 413 Table 19. Recovery of alfalfa I-15 in inorganic soil I at IL. 710 DISCRIPTIOI 71R DESCRIPTIOI 1 Plot I 2 Replication 3 Plant Part 1=Sboot 2=Rootlcrovn 1 Tine of Incorporation 1=Iall 2=Spring 5 0-15 Total Layer 0.0. (r) 6 15-30 Total Layer 0.0. (r) 7 30-15 Total Layer 0.8. (8) 8 15-60 Total Layer 0.I. (g) 9 0-15 Inorganic I (ug/g) 10 15-30 Inorganic I (ug/g) 11 30-15 Inorganic I (ug/g) 12 15-80 Inorganic I (ug/g) 13 0-15 Inorganic I I-15 Iton I Ixcess 11 15-30 Inorganic I I-15 Iton I Excess 15 30-15 Inorganic I I-15 Iton I Ixcess 16 15-60 Inorganic I I-15 Iton I Incess 17 0-15 Inorganic I-15 Recovery (I of input) 18 15-30 Inorganic I-15 Recovery (I of input) 19 30-15 Inorganic I-15 Recovery (I of input) 20 15-60 Inorganic I-l5 Recovery (I of input) 21 0-80 Inorganic I-15 Recovery (I of input) 0886 IL 12 3 1 5 6 7 8 9 10 11 12 13 11 15 16 1 101 1 2 1 16812 51767 86038 51538 18.0 11. 1 5. 3 L 28919 0. 08128 0 02820 L 02090 2 102 1 1 1 15765 13661 38389 18825 19.3 11. 1 7. 8 L 31277 L 08513 0. 01512 L 03708 3 103 1 2 2 18328 53152 56151 19315 18.8 11. 8 7. 7 0. 33353 0.16266 L 03998 0. 02981 1 101 1 1 2 19356 17106 58615 18291 2L 2 15.8 9. 8 0. 39892 0. 29085 0. 08131 L 01571 5 201 2 2 2 51092 19103 72965 62351 15.8 9. 9 1. 8 0. 31803 0. 08618 L 03017 L 03550 6 202 2 1 2 15190 18717 53397 62821 16.5 12.1 8. 6 L 39986 0. 22737 L 01138 0. 01811 7 203 2 1 1 17601 57120 67889 63010 18.8 18. 1 7. 6 0. 36310 0.10956 0.01363 0 02010 8 201 2 2 1 15871 15693 81757 82619 17.1 15.6 0. 8 0. 27823 0.11818 L 02687 L 01153 9 301 3 1 1 15858 53631 68827 57715 15. 1 11. 9 L 8 0. 31312 0. 09918 0.01121 L 03632 10 302 3 1 2 13195 17517 61892 59852 12:7 11.5 1.6 0.11171 0.17331 0. 05098 0. 01308 11 303 3 2 1 17086 13821 19991 11275 12.3 8. 3 5.2 L 31289 0. 06535 0. 02339 0.01559 12 301 3 2 2 11261 50960 78658 61951 11. 1 11. 1 9. 6 L 35812 L 13538 0. 01125 0 00550 13 101 1 2 2 15301 11556 53789 59631 16.9 12.7 8. 5 I. 27152 0.18286 L 05515 0. 02587 11 102 1 2 1 13915 12780 61115 55558 15.0 11.2 L 7 L 25156 0 09185 0. 03383 0. 02108 15 103 1 1 2 53831 51113 71352 89022 1L 8 11. 1 8. 0 L 31177 0.18080 L 10055 0. 07583 18 101 1 1 1 16097 51208 58811 67017 15.8 11. 8 7. 6 L 33910 L 11857 L 01398 L 05117 17 18 19 20 21 1 1.08 0.21 0.06 0.03 1.38 2 1.15 0.16 0.05 0.05 1.11 3 1.29 0.15 0.08 0.05 1.87 1 1.50 0.82 0.11 0.08 2.51 5 1.23 0.19 0.08 0.05 1.51 6 1.11 0.51 0.08 0.10 1.83 7 1.10 0.39 0.10 0.09 1.88 8 0.96 0.16 0.06 0.03 1.51 9 0.92 0.21 0.06 0.09 1.30 10 0.93 0.38 0.09 0.11 1.19 11 0.80 0.10 0.02 0.01 0.91 12 0.99 0.35 0.02 0.01 1.38 13 0.92 0.13 0.08 0.06 1.18 11 0.71 0.20 0.07 0.08 1.07 15 1.39 0.12 0.19 0.16 2.17 16 0.91 0.28 0.08 0.10 1.38 4f? Table 110. Recovery of alfalfa I-15 in Inorganic soil I at 108. 71R DISCRIPTIOI Plot I Plant Part 1=Sboot 2=Rootlcrovn 0-15 Total Layer 0.I. (g) 30-15 Total Layer 0.I. (g) 0-15 Inorganic I (ug/g) 30-15 Inorganic I (ug/g) 71R 2 I8 18 13 0-15 Inorganic I I-15 Iton I Ixcess 15 30-15 Inorganic I l-15 Iton I Ixcess 17 0-15 Inorganic I-15 Recovery (I of input) 19 30-15 Inorganic I-15 Recovery (I of input) 20 21 0-60 Inorganic l-15 Recovery (I of input) 018! I0. 1 2 3 1 5 6 7 8 9 1 101 1 1 1 50276 61168 55109 82233 19. 2 2 102 1 1 2 58987 51327 19111 11270 2L 0 3 103 1 2 2 57268 52596 52120 80357 16.9 1 101 1 2 1 17399 15165 55818 58071 18.7 5 201 2 2 2 55886 53863 60028 61686 22. 1 6 202 2 1 2 60739 61926 88310 61808 3.9 7 203 2 2 1 51809 51176 58313 61359 21.0 8 201 2 1 1 50031 65865 62392 11739 2L 5 9 301 3 2 1 17521 58753 57151 60371 2L 2 10 302 3 1 2 59931 56683 56982 59267 15. 9 11 303 3 1 1 50611 16820 52111 18086 26. 5 12 301 3 2 2 62531 52610 53556 17655 21. 9 13 101 1 2 2 51202 77610 62196 56382 19. 1 11 102 1 2 1 52318 67365 86797 59081 1L 6 15 103 1 1 2 51921 51363 82812 68536 17.7 18 101 1 1 1 19868 55906 60611 83727 19. 2 17 18 19 20 21 1 2.00 0.82 0.22 0.06 3.10 2 2.13 0.57 0.21 0.11 3.35 3 1.82 0.30 0.01 0.03 2.18 1 1.10 0.56 0.15 0.07 2.17 5 1.31 0.13 0.01 0.02 1.82 6 0.35 0.38 0.01 0.03 0.80 7 1.15 0.17 0.07 0.05 2.05 8 2.12 0.61 0.06 0.01 2.85 9 1.35 0.79 0.10 0.10 2.31 10 2.01 0.62 0.17 0.12 2.95 11 2.20 0.17 0.11 0.26 3.01 12 2.21 0.70 0.16 0.08 3.18 13 1.86 0.62 0.33 0.11 2.96 11 1.88 0.55 0.20 0.06 2.66 15 2.01 0.11 0.11 0.12 2.71 16 0.27 0.78 0.13 0.18 1.38 DESCRIPTIOI Replication Tine of Incorporation 1=Iall 2=Spring 15-30 Total Layer 0.I. (g) 15-60 Total Layer 0.8. (g) 15-30 Inorganic I (ug/g) 15-60 Inorganic I (ug/g) 15-30 Inorganic I I-15 Iton I Ixcess 15-80 Inorganic I I-15 Iton I Ixcess 15-30 Inorganic I-15 Recovery (I of input) 15-80 Inorganic I-15 Recovery (I of input) .51155 L 23381 0.11226 L 03970 .18972 0. 20295 L 12350 L 22235 .12522 0.10801 L 00912 0.01398 .35877 L 18863 L 05982 L 03188 .21251 0.11897 0. 01081 0. 01053 .39288 L 13589 0. 01177 L 01718 .30235 0.15815 0. 05223 0. 03105 .51176 L 21720 L 05802 0. 02621 .31857 0.17585 L 05003 0. 01211 .56353 L 22368 L 08581 0. 08310 .13097 L 20880 0. 01771 0. 22387 .32131 0.18732 L 01717 L 03139 .39983 0.19172 0.11628 L 06600 .10832 0.18178 L 06062 0. 01779 .55157 L 25108 0. 08121 0. 08226 .07396 L 26779 L 05750 0. 08112 °°°°°°°°°°°°°°°° 48 Table A11. Microbial biomass carbon at EL. LIST OF VARIABLES VAR TYPE NAME/DESCRIPTION 1 numeric Plot 0 2 numeric Replication 3 numeric Plant Part 1=Sboot 2=Root/crown 4 numeric Time of Incorporation 1=Fall 2=Spring 5 numeric Carbon Flush for Fumigation/lO day Incubation — Cf (ug/g) 6 numeric Carbon Evolved from Unfumigated/IO day Incubation - C10 (ug/g) 7 numeric Carbon Evolved from Unfumigated/ZO day Incubation — 020 (ug/g) 8 numeric Microbial Biomass Carbon - Cf/0.41 (us/g) CASE NO 1 2 3 4 5 6 7 8 1 101 1 2 1 232.0 122.3 86.8 565.9 2 102 1 1 1 245.4 102.3 102.0 598.5 3 103 1 2 2 228.3 64.0 46.9 556.8 4 104 1 1 2 217.1 44.6 44.6 529.5 5 201 2 2 2 173.7 81.4 71.1 423.7 6 202 2 1 2 234.3 102.6 49.1 571.5 7 203 2 1 1 209.1 90.8 51.4 510.0 8 204 2 2_ 1 231.7 100.3 53 7 565.1 9 301 3 1 1 223.7 105.1 67.4 545.6 10 302 3 1 2 218.0 98.8 94.0 531.7 11 303 3 2 1 233.4 142.6 90.0 569.3 12 304 3 2 2 220.8 123.7 76.9 538.5 13 401 4 2 2 219.7 98.3 53.1 535.9 14 402 4 2 1 254.3 55.7 55.7 620.2 15 403 4 1 2 220.0 106.0 42.6 536.6 16 404 4 1 1 213.4 100.8 59.7 520.5 49 Table A12. Microbial biomass carbon at KBS. LIST OF VARIABLES VAR TYPE NAME/DESCRIPTION 1 numeric Plot 8 2 numeric Replication 3 numeric Plant Part 1=Sboot 2=Root/crown 4 numeric Time of Incorporation 1=Fall 2=Spring 5 numeric Carbon Flush for Fumigation/10 day Incubation - Cf (ug/g) 6 numeric Carbon Evolved from Unfumigated/lO day Incubation - C10 (ug/g) 7 numeric Carbon Evolved from Unfumigated/ZO day Incubation — C20 (ug/g) 8 numeric Microbial Biomass Carbon — Cf/0.41 (ug/g) CASE NO 1 2 3 4 5 6 7 8 1 101 1 1 1 155.7 80.0 80.0 379.8 2 102 1 1 2 120.0 55.4 55.4 292.7 3 103 1 2 2 155.1 89.7 84.8 378.3 4 104 1 2 1 136.6 55.1 57.4 333.2 5 201 2 2 2 137.4 84.8 84.8 335.1 6 202 2 1 2 103.4 68.3 71.7 252.2 7 203 2 2 1 103.1 58.3 78.3 251.5 8 204 2 1 1 102.8 84.6 33.1 250.7 9 301 3 2 1 198.8 102.8 74.3 484.9 10 302 3 1 2 110.0 61.4 11.7 268.3 11 303 3 1 1 81.1 92.8 1.4 197.8 12 304 3 2 2 92.3 58.6 37.4 225.1 13 401 4 2 2 106.6 62.9 53.4 260.0 14 402 4 2 1 115.7 78.3 71.1 282.2 15 403 4 1 2 79.1 85.4 55.7 192.9 16 404 4 1 1 113.4 88.6 41.1 276.6 550 Table 113. Iicrobial bionass I and recovery of alfalfa I-15 in nicrobial bionass at IL. LIST 0! IIRIIRLIS 71R TIPI IIIR/DISCRIPTIOI 1 nuneric Plot 1 2 nuneric Replication 3 nuneric Plant Part 1=Sboot 2=Root/crovn 1 nuneric Tine of Incorporation 5 nuneric 0-15 Total Layer 0.I. (g) 6 nuneric Initial l03 Concentration (ppn) 7 nuneric Initial I01 Concentration (ppn) 8 nuneric Iunigated/lo day Incubation I03 Concentration (ppn) 9 nuneric Iunigated/10 day Incubation IR1 Concentration (ppn) 10 nuneric 0nfunigated/20 day Incubation I03 Concentration (ppn) 11 nuneric 0nfunigated/20 day Incubation I81 Concentration (ppn) l2 nuneric litrogen Ilusb - If (ug/g) 13 nuneric Carbon Ilusb -Cf (ug/g) 11 nuneric In - -0.011(Cf/If) + 0.39 15 nuneric Iicrobial Rionass I - If/In (ug/g) 16 nuneric Innigated/lo Incubation Inorganic I I-15 Iton I chess 17 nuneric Recovery of alfalfa l-15 in Iicrobial Bionass (I of input) C868 IL12315678910111213111516 1 101 1 2 1 16812 1. 26 L 00 0.93 1.16 3.50 0. 00 20. 80 232. 0 L 231 88. 9 0.13016 7. 91 2 102 1 1 1 15765 1.13 0. 00 0.93 1.11 3. 91 0. 00 22.05 21L 1 0.231 91. 2 L 51329 8. 89 3 103 1 2 2 16328 1.31 0.00 0.88 1.17 3.31 0. 00 22.35 228. 3 0. 217 90. 5 0.16772 8. 69 1 101 1 1 2 19358 1.16 0.00 1.16 1.58 3. 62 0. 00 22.90 217.1 0.257 89. 0 0. 80317 10. 07 5 201 2 2 2 51092 i. 07 0. 00 0.52 3.58 2.81 L 00 17.90 173. 7 L 251 70.1 0. 50259 8. 02 6 202 2 1 2 15190 1. 36 0. 00 0.76 1.12 3. 38 0. 00 22.10 231.3 L 212 91.5 0. 63517 1L 05 7 203 2 1 1 17601 1.09 0.00 0.52 1.13 2. 80 0. 00 22.15 209.1 0. 258 85. 9 0. 60709 9.13 8 201 2 2 1 15871 1.28 0.00 0.98 1.78 3. 55 0. 00 23. 90 231. 7 0.251 91.0 0. 39912 7. 83 9 301 3 1 1 15858 0.95 0.00 0.59 1.28 3.15 0. 00 21.10 223. 7 0.211 87. 8 0. 51136 7. 83 10 302 3 1 2 13195 0. 92 0. 00 0.18 1.10 3.11 L 00 22.00 218. 0 L 251 87.6 0. 77995 11.28 11 303 3 2 1 17086 L 88 L 00 0.53 1.27 3. 23 0. 00 21.35 23L 1 L 237 90.1 0.10168 7. 61 12 301 3 2 2 11261 1.01 0.00 0.58 1.15 L 38 L 00 20. 75 220. 8 L 211 86.1 0 15288 L 65 13 101 1 2 2 15301 1.11 0.00 0.82 1.80 3.11 0. 00 23.00 219. 7 0.258 89. 7 0.18581 11 102 1 2 1 13915 1.03 0.00 0.75 1.56 3. 25 0. 00 22.80 251.3 0.231 97. 5 L 10828 7. 75 15 103 1 1 2 53831 1. 05 L 00 0.81 1.31 3.30 0. 00 21.70 220. 0 0.218 87.5 0. 72888 13.01 16 101 1 1 1 16097 1.11 L 00 0.71 1.12 3.33 L 00 2L 60 213.1 0.215 81.1 0.19518 7. 30 511 Table 111. Iicrobial bionass I and recovery of alfalfa I-15 in nicrobial bionass at 388. LIST OF TIRIIBLIS 71R TTPI l1II/018881PTIOI 1 nuneric Plot 1 2 nuneric Replication 3 nuneric Plant Part 1=Sboot 2=Rootlcrovn 1 nuneric Tine of Incorporation 5 nuneric 0-15 Total Layer 0.8. (g) 6 nuneric Initial l03 Concentration (PPn) 7 nuneric Initial I81 Concentration (ppn) 8 nuneric Iunigated/10 day Incubation 803 Concentration (ppn) 9 nuneric Iunigated/10 day Incubation I81 Concentration (ppn) 10 nuneric 0nfunigated/20 day Incubation I03 Concentration (ppn) 11 nuneric 0nfunigated/20 day Incubation I81 Concentration (ppn) 12 nuneric litrogen Ilusb - If (ug/g) 13 nuneric Carbon Tlusb -Cf (ug/g) 11 nuneric In - -0.011(Cf/If) t 0.39 15 nuneric Iicrobial Rionass I - If/In (ug/g) 16 nuneric Iunigated/IO Incubation Inorganic I [-15 1ton I Ixcess 17 nuneric Recovery of alfalfa I-15 in Iicrobial Bio-ass (I of input) C181 I0. 1 2 3 1 5 8 7 8 9 10 11 12 13 11 15 1 101 1 1 1 50216 1. 21 L 00 1.37 2.58 1. 88 0. 00 12.90 155. 7 0.221 58 1 2 102 1 1 2 56987 1. 71 0. 00 1.85 2.50 1.11 0. 00 12.50 120 0 0.258 18 9 3 103 1 2 2 57268 1. 22 0. 00 1.17 2.37 1.07 L 00 11.85 155. 1 0. 207 57 3 1 101 1 2 1 17399 1. 51 L 00 1.62 2.10 1. 53 0. 00 10. 50 136. 6 0. 208 50 5 5 201 2 2 2 55886 1.19 0.00 1.65 2.08 1.67 0. 00 1L 10 137.1 0.205 50 7 6 202 2 1 2 80739 1.70 0.00 1.86 2.21 5.03 0 00 11.05 10L 1 0. 259 12 7 7 203 2 2 1 51609 1.57 0.00 1.62 1.96 3.89 0 00 9.80 103. 1 L 213 1L 1 8 201 2 l 1 50031 1.73 L 00 1.72 1.97 1.79 0 00 9.85 102. 8 0.211 1L 1 0. 81700 9 301 3 2 1 17521 1. 80 0. 00 1.59 1.88 1.92 0 00 9.10 198. 8 0.091 10L 1 10 302 3 1 2 59931 1.13 L 00 1.20 1.95 3.16 0 00 9.75 110 0 0.232 12 0 11 303 3 1 1 50611 1. 22 L 00 1.60 1.72 1.01 0 00 8.60 81.1 0.258 33 3 12 301 3 2 2 62531 1. 97 0. 00 2.01 1.85 1.69 0 00 9.25 92. 3 0. 250 37 0 13 101 1 2 2 51202 2. 20 0. 00 1.91 2.30 5.25 0. 00 11.50 106. 6 L 260 11 2 11 102 1 2 1 52318 1. 65 0. 00 1.59 2.31 1.11 0. 00 11. 70 115. 7 0.252 16 5 15 103 1 1 2 51921 1. 33 L 00 1.21 2.15 3.92 0 00 IL 75 79.1 0. 287 37 5 16 101 1 1 1 19888 1. 68 0. 00 1.50 2.31 1.18 0. 00 11. 70 113.1 L 251 16 0 0.15671 L 60 6. 50 9. 83 9.15 1.97 5.21 5.11 5.81 552 Table 115. I-15 aton I of total I and inorganic l in soil sanples fron the 60-75 on depth at IL and IRS. LIST OI IIRIIBLIS 718 TTPI IIII/DISCRIPTIOI l nuneric Plot 1 2 nuneric Total I I-15 1ton I 80-75 : IL 3 nuneric Total I I-15 1ton I 80-75 : I88 1 nuneric Inorganic I I-15 1ton I 80-75 : IL 5 nuneric Inorganic l I-15 1ton I 60-75 : IRS 1 101 0.38998 0.39512 0.37680 0.37805 2 102 0.38812 0.11210 0.37553 0.51985 3 103 0.38787 0.37879 0.39753 0.37292 1 101 0.37028 0.39021 0.38985 0.38303 5 201 0.37197 0.38235 0.39213 0.38285 8 7 8 9 202 0.37129 0.38590 0.39763 0.36871 203 0.37025 0.38359 0.38768 0.38189 201 0.37161 0.10633 0.38358 0.39908 301 0.37857 0.38881 0.10610 0.39389 10 302 0.38137 0.38512 0.11611 0.39366 11 303 0.37255 0.38918 0.38077 0.38978 12 301 0.37012 0.38859 0.37118 0.37797 13 101 0.38998 0.37885 0.38010 0.39082 11 102 0.38179 0.38213 0.12962 0.38789 15 103 0.37768 0.10115 0.11312 0.11191 16 101 0.37813 0.38071 0.39258 0.39957 17 18 1 0.37137 0.37883 19 2 0.38825 0.37237 20 3 0.36957 0.37107 21 1 0.38812 0.36178 22 5 0.36832 0.38895 23 6 0.38931 0.37881 Table 118. I nineralixation potential and percent nineralised I 553 derived fron alfalfa at IL and IRS. 718 TIPR I1IR/DISCRIPTIOI 1 nuneric Location 1=IL 2:188 2 nuneric Plot I 3 nuneric Replication 1 nuneric Plant Part 1=Sboot 2=Root/crovn 5 nuneric Tine of Incorporation 1=Tall 2=Spring 8 nuneric 0nfunigated Tine Iero I03-I (ppn) 7 nuneric 0nfunigated 20-day I03-I (ppn) 8 nuneric I nineraliration capacity (ug/g) 9 nuneric I-15 aton I excess of nineralized I (20-day I03) 10 nuneric Percent nineraliaed I derived fron alfalfa CISI IO. 1 2 3 1 5 6 7 8 9 10 1 1 101 1 2 1 1.26 3.50 11.20 L 37079 5.36 2 1 102 1 1 1 1.13 3.91 12.10 0.18017 6.91 3 1 103 1 2 2 1.31 3.31 10. 00 L 15611 6.59 1 1 101 1 1 2 1.18 3.62 10.80 0.53789 7.77 5 1 201 2 2 2 1.07 2.81 8. 70 0.19790 7.19 8 1 202 2 1 2 1.36 3.38 1L 10 0. 56155 8.11 7 1 203 2 1 1 1.09 2.60 7. 55 L 52275 7.55 8 1 201 2 2 i 1.28 3.55 11.35 0. 38771 5.31 9 1 301 3 1 1 0.95 3.15 12.50 0.17018 6.80 10 1 302 3 1 2 0.92 3.11 10.95 0.66875 9.66 11 1 303 3 2 1 0.86 3.23 11.85 0.37682 5.11 12 1 301 3 2 2 1.01 3.36 11.75 0.11980 8.50 13 1 101 1 2 2 1.11 3.11 10.00 0.11775 6.17 11 1 102 1 2 1 1.03 3.25 11.10 0.37117 5.11 15 1 103 1 1 2 1.05 3.30 11.25 0.62377 9. 01 16 1 101 1 1 1 1.11 3.33 10.95 0.13815 L 33 17 2 101 1 l 1 1.21 1.68 17.20 0. 72353 1L 15 18 2 102 1 l 2 1.71 1.11 13.50 L 88105 9. 88 19 2 103 1 2 2 1.22 1.07 11. 25 L 51171 7. 83 20 2 101 1 2 1 1.51 1.53 11.95 L 18915 7. 07 21 2 201 2 2 2 1.19 1.67 15.90 L 28668 18.59 22 2 202 2 1 2 1.70 5.03 16.65 1.08711 15.71 23 2 203 2 2 1 1.57 3.89 11.60 L 12578 6.15 21 2 201 2 1 1 1.73 1.79 IL 30 L 88009 9. 83 25 2 301 3 2 1 1.60 1.92 1L 60 L 91170 13.60 26 2 302 3 1 2 1.13 3.16 11. 85 0. 95289 13.77 27 2 303 3 l 1 1.22 1.01 13.95 L 17705 8. 89 28 2 301 3 2 2 1.97 1.89 13.60 0. 91893 13.71 29 2 101 1 2 2 2.20 5.25 15.25 0. 81216 12.17 30 2 102 1 2 1 1.65 1.11 13.95 0. 59799 8. 61 31 2 103 1 1 2 1.33 3.92 12.95 L 57101 8. 29 32 2 101 1 1 1 1.66 1.18 11. 10 0. 81129 8. 83 5&4 Table 117. Spring barley dry natter yield, I content, percent I derived fron alfalfa and total I uptake at IL. DISCRIPTIOI 1 Plot 1 2 Replication 3 PP lzsboot 2=rootlcrovn 1 701 1=fall 2=spring 5 Grain 0.8. Iield (g/plot) 6 Stover R.I. Iield (g/plot) 7 Root 0.8. Yield 8 Grain II 9 Stover II 718 13 DISCRIPTIOI Root I-15 aton I excess Grain IIDII Stover IIDII Root IIDII Grain TIO (g/plot) Stover T10 (g/plot) Roots TIO (g/plot) Grain + Stover 1 Roots TII (g/plot) 10 Root II 21 Grain + Stover + Roots 0.8. Yield (g/plot) 11 Grain I-15 aton I excess 22 Grain + Stover + Roots II 12 Stover I-15 aton I excess 23 IIDI1 in Grain 1 Stover 1 Roots CISI I0. 1 2 3 1 5 6 7 8 10 11 12 13 11 15 1 101 l 2 1 11.11 32. 93 21.51 1. 512 0. 371 L 582 0. 23730 0. 23708 L 21971 3. 39 3. 39 3.17 2 102 1 1 1 57.77 32.70 20. 07 1. 517 L 389 0. 530 0. 26806 0. 25801 0. 21799 3. 32 3. 20 3.07 3 103 1 2 2 39.98 26.62 12.09 1. 577 L 521 0. 751 0. 26521 0. 26153 0. 21658 3. 79 3. 78 3.56 1 101 1 1 2 58. 62 33. 39 11.20 1. 533 L 119 L 721 0. 31916 0. 29838 0.18392 3. 95 3. 70 2.28 5 201 2 2 2 33.18 27. 52 11.21 1. 527 0.171 L 682 L 30186 0.26779 0. 26595 1. 36 3. 83 3.81 6 202 2 1 2 56. 78 38. 62 18.89 1.167 L 383 L 601 0. 38581 L 35731 0. 31088 1. 78 1.13 1.22 7 203 2 1 1 6L 20 36. 98 11.98 1.533 0.108 0.751 0. 30156 0. 29968 0. 27818 3. 77 L 71 3.15 8 201 2 2 1 65. 93 11.09 17.21 1.611 0. 579 L 725 0. 23879 L 23967 L 21110 L 12 3.13 3.53 9 301 3 1 1 38.18 32.61 13.73 1. 382 L 161 0. 727 L 33510 0. 27331 L 27316 1.15 3. 39 3.38 10 302 3 1 2 37.12 33.56 11.90 1.336 L 109 L 859 0.11029 L 11910 0. 39157 5.15 L 19 1.85 11 303 3 2 1 51. 39 11.33 11. 18 1.285 L 381 0. 776 0.26158 0. 21871 L 22312 3. 71 3. 56 3.23 12 301 3 2 2 11.28 31. 91 10. 50 1. 372 L 190 1. 000 L 31180 0. 33017 0. 26088 1. 89 1. 72 3.77 13 101 1 2 2 15.82 37.26 9. 21 1.153 0. 393 L 935 0 28026 0. 26112 0 23167 1. 01 3. 71 3.39 11 102 1 2 1 3L 39 35. 01 10.10 1.172 0.166 0. 723 0. 25797 0.21558 0. 22115 3. 69 3. 51 3.21 15 103 1 1 2 12.10 31.97 13.00 1. 538 L 115 0. 697 L 11758 0. 39070 L 33778 5.17 1. 81 1.18 16 101 1 1 1 17.19 35.08 11.28 1. 387 0. 370 0. 757 0. 27579 0. 26970 0. 25012 3.12 3. 31 3.10 17 18 19 20 21 22 23 l 0.68 0.12 0.11 0.95 101.6 0.93 3.36 2 0.89 0.12 0.11 1.12 110.5 1.01 3.28 3 0.83 0.11 0.09 0.86 78.7 1.09 3.77 1 0.90 0.11 0.10 1.11 106.2 1.07 3.77 5 0.51 0.13 0.08 0.71 71.9 0.99 1.21 6 0.83 0.15 0.11 1.09 111.3 0.98 1.67 7 0.92 0.15 0.11 1.19 112.2 1.06 3.73 8 1.08 0.21 0.12 1.13 121.3 1.15 3.13 9 0.53 0.15 0.10 0.78 81.8 0.92 3.91 10 0.50 0.11 0.08 0.72 82.9 0.86 5.31 11 0.85 0.16 0.09 0.89 103.9 0.86 3.66 12 0.57 0.17 0.11 0.81 86.7 0.97 1.71 13 0.67 0.15 0.09 0.90 92.3 0.97 3.90 11 0.52 0.16 0.08 0.76 80.8 0.91 3.61 15 0.65 0.16 0.09 0.89 90.1 0.99 5.01 18 0.66 0.13 0.09 0.87 93.9 0.93 3.37 555 Table 118. Spring barley dry natter yield, I content, percent I derived fron alfalfa and total I uptake at IRS. lot) DISCRIPTIOI 719 DISCRIPTIOI Plot 1 13 Root I-15 aton I excess Replication 11 Grain IIDI1 PP 1=sboot 2=root/crovn 15 Stover IIDII T01 1=fail 2=spring 16 Root IIDI1 Grain R.I. Iieid (g/plot) 17 Grain T80 (g/plot) Stover 0.8. Iield (g/plot) 18 Stover TIO (g/plot) Root 0.8. Yield 19 Root TIO (g/plot) Grain II 9 Stover II 20 Grain + Stover 1 Root TIR (g/plot) Root II 21 Grain + Stover + Roots 0.8. Tield (g/p Grain l-15 aton I excess 22 Grain + Stover 1 Roots II Stover I-15 aton I excess 23 Grain t Stover + Roots IIDII 1 2 3 1 5 7 8 9 10 11 12 13 11 101 1 1 l 11.31 21.20 9.21 2. 636 1.102 L 931 0. 50286 0.17511 0. 50100 6. 23 102 1 1 2 2L 57 25.67 1L 10 2. 518 1.181 1.068 0.19812 L 17111 0.15110 6.17 103 1 2 2 13 59 32.23 13.00 2.107 1. 089 1. 057 L 37011 0. 31559 0. 36972 5. 29 101 1 2 1 17.37 17.90 11.28 2.301 0. 985 0. 896 L 38905 0. 37597 0. 31077 5. 56 201 2 2 2 16.81 21. 31 L 50 2.310 L 981 1. 225 0 28716 0. 28711 0. 27953 L 11 202 2 1 2 16.75 25.31 1.50 2 168 1.322 0. 960 L 18398 0.19301 0.11283 5. 99 203 2 2 1 13.06 20.86 8.51 2 131 1.101 1.125 0. 32225 L 31929 0. 31883 1. 81 201 2 1 1 12.99 20.31 3.56 2.110 0. 988 1.030 0.19880 L 17057 L 18962 8.18 301 3 2 1 11.08 17.83 1.32 2.635 1. 088 1. 019 L 29199 L 28998 0. 28185 1.18 302 3 l 2 19.91 18.69 9.98 2.088 1.168 1. 011 0. 51111 L 53881 L 52316 6. 71 303 3 1 1 17.08 19.31 2.97 2.590 1.127 L 986 0. 51313 0. 50781 L 52215 8. 73 301 3 2 2 21.01 21.31 8.31 2 178 1.077 L 801 0. 31007 0. 33211 0. 30811 1. 86 101 1 2 2 15.12 19.83 5.32 2 171 1.208 1.011 L 35813 0. 31720 0. 35557 5.12 102 1 2 1 11.19 19.10 6.20 2 293 1.261 1. 073 0.10151 0. 38192 L 36780 5. 71 103 1 1 2 13.52 17.21 3.91 2 825 1 171 1.127 0. 53116 L 53190 0.18359 6. 62 101 1 1 1 10.58 17.17 7. 66 2.171 1.508 L 862 L 19791 L 19715 161090. 6.17 17 18 19 20 21 22 23 0.30 0.23 0.09 0.62 11.8 1.18 6.10 0.52 0.30 0.11 0.91 56.8 1.66 6.01 0.33 0.35 0.11 0.82 58.8 1.39 1.97 0.10 0.18 0.10 0.68 18.5 1.16 5.12 0.39 0.21 0.08 0.66 12.7 1.51 1.01 0.11 0.33 0.01 0.79 16.6 1.70 6.01 0.32 0.23 0.07 0.82 10.5 1.51 1.75 0.31 0.20 0.01 0.55 38.9 1.19 8.01 0.37 0.19 0.01 0.60 36.0 1.67 1.16 0.12 0.22 0.10 0.73 18.6 1.51 8.88 0.11 0.22 0.03 0.89 39.1 1.75 8. 58 0.52 0.23 0.07 0.82 50.7 1.61 1. 80 0.38 0.21 0.05 0.67 10.8 1.66 5. 07 0.26 0.21 0.07 0.56 36.5 1.55 5.57 0.38 0.25 0.01 0.68 31.8 1.96 6.57 0.26 0.26 0.07 0.59 35.1 1.66 8.11 513 Table 119. Recovery of alfalfa I-15 by spring barley at 81. 78R DESCRIPTIOI 71R 0888818710! 1 Plot 8 11 Grain 8-15 aton I excess 2 Rep1ication 12 Stover I-15 aton I excess 3 PP 1=sboot 2=root/crovn 13 Root I-15 aton I excess 1 701 1=fall 2=sprin¢ 11 Grain I8081 5 Grain 0.8. 7ield (s/plot) 15 Stover IIDIA 6 Stover 0.8. Tield (g/plot) 16 Root IIDIA 7 Root 0.8. Yield 17 Recovery by grain (I of input) 8 Grain II 18 Recovery by stover (I of input) 9 Stover II 19 Recovery by roots (I of input) 10 Root II 20 Recovery by grain+stover+roots (I of input) 0888 IO. 1 2 3 1 5 8 7 8 9 10 11 12 13 11 15 18 1 101 1 2 1 11 11 32.93 21.51 1.512 0.371 0.582 0.23730 0.23708 0.21971 3.39 3.39 3.17 2 102 1 1 1 57.77 32.70 20.07 1.517 0.389 0.530 0.26806 0.25801 0.21799 3.32 3.20 3.07 3 103 1 2 2 39.98 26.62 12.09 1.577 0.521 0.751 0.28521 0.26153 0.21858 3.79 3.78 3.56 1 101 1 1 2 58.82 33.39 11.20 1.533 0.119 0.721 0.31918 0.29838 0.18392 3.95 3.70 2.28 5 201 2 2 2 33.18 27.52 11.21 1.527 0.171 0.882 0.30186 0.28779 0.28595 1.36 3.83 3.81 8 202 2 1 2 58.78 38.62 18.89 1.187 0.383 0.601 0.38561 0.35731 0.31088 1.78 1.13 1.22 7 203 2 1 1 80.20 38.98 11.98 1.533 0.108 0.751 0.30158 0.29968 0.27818 3.77 3.71 3.15 6 201 2 2 1 85.93 11.09 17.21 1.811 0.579 0.725 0.23679 0.23967 0.21110 3.12 3.13 3.53 9 301 3 1 1 38.18 32.81 13.73 1.382 0.161 0.727 0.33510 0.27331 0.27318 1.15 3.39 3.38 10 302 3 1 2 37.12 33.56 11.90 1.336 0.109 0.859 0.11029 0.11910 0.39157 5.15 5.19 1.85 11 303 3 2 1 51.39 11.33 11.18 1.285 0.381 0.778 0.26158 0.21671 0.22312 3.71 3.56 3.23 12 301 3 2 2 11.28 31.91 10.50 1.372 0.190 1.000 0.31180 0.33017 0.28086 1.89 1.72 3.77 13 101 1 2 2 15.82 37.28 9.21 1.153 0.393 0.935 0.28026 0.28112 0.23187 1.01 3.71 3.39 11 102 1 2 1 35.39 35.01 10.10 1.172 0.166 0.723 0.25797 0.21558 0.22115 3.69 3.51 3.21 15 103 1 1 2 12.10 31.97 13.00 1.538 0.115 0.897 0.11758 0.39070 0.33778 5.17 1.81 1.18 16 101 1 1 1 17.19 35.08 11.28 1.387 0.370 0.757 0.27579 0.26970 0.25012 3.12 3.31 3.10 17 18 19 20 1 0.72 0.13 0.11 0.98 2 0.91 0.12 0.10 1.13 3 0.71 0.16 0.10 1.00 1 1.09 0.16 0.07 1.32 5 0.68 0.15 0.09 0.93 6 1.22 0.20 0.15 1.57 7 1.07 0.17 0.12 1.38 8 1.13 0.25 0.11 1.51 9 0.67 0.16 0.10 0.93 10 0.81 0.22 0.12 1.17 11 0.75 0.17 0.09 1.01 12 0.88 0.25 0.12 1.23 13 0.83 0.17 0.09 1.09 11 0.60 0.18 0.07 0.85 15 1.03 0.23 0.12 1.37 18 0.89 0.13 0.08 0.90 537 Table 120. Recovery of alfalfa I-15 by spring barley at [88. 71R DISCRIPTIOI 71R DESCRIPTIOI 1 Plot 8 11 Grain I-15 aton I excess 2 Replication 12 Stover I-15 aton I excess 3 PP 1=sboot 2=root/croun 13 Root I415 aton I excess 1 701 1=fall 2=spring 11 Grain IIDII 5 Grain 0.8. Tield (g/plot) 15 Stover IIDFI 6 Stover 0.8. Yield (g/plot) 16 Root IIDFI 7 Root 8.8. Yield 17 Recovery by grain (I of input) 8 Grain II 18 Recovery by stover (I of input) 9 Stover II 19 Recovery by roots (I of input) 10 Root II 20 Recovery by grain+stover+roots (I of input) 018! I0.1231 5 8 7 8910 111516 1 101 1 1 1 11.31 21.20 9.21 2.838 1.102 0.931 0.50288 0.17511 0.50100 6.23 5.89 8.20 2 102 1 1 2 20.57 25.67 10.10 2.518 1.181 1.068 0.19812 0.17111 0.15110 6.17 5.88 5.59 3 103 1 2 2 13.59 32.23 13.00 2.107 1.089 1.057 0.37011 0.31559 0.36972 5.29 1.51 5.31 1 101 1 2 1 17.37 17.90 11.28 2.301 0.985 0.898 0.38905 0.37597 0.31077 5.56 5.38 1.92 5 201 2 2 2 16.81 21.31 1.50 2.310 0.981 1.225 0.28718 0.28711 0.27953 1.11 3.82 1.01 6 202 2 1 2 18.75 25.31 1.50 2.188 1.322 0.980 0.18398 0.19301 0.11283 5.99 6.11 5.18 7 203 2 2 1 13 06 20.86 6.51 2.131 1.101 1.125 0.32225 0.31929 0.31883 1.81 5.00 1.61 8 201 2 1 1 12.99 20.31 3.58 2 110 0.988 1.030 0.19880 0.17057 0.18982 8.18 5.83 6.06 9 301 3 2 1 11.08 17.63 1.32 2.635 1.088 1.019 0.29199 0.28998 0.28185 1.18 1.15 1.12 10 302 3 1 2 19.91 18 89 9.98 2.086 1.166 1.011 0.51111 0.53881 0.52318 8.71 6.67’ 6.18 11 303 3 1 1 17.08 19.31 2.97 2.590 1.127 0.988 0.51313 0.50761 0.52215 6.73 6.29 8.17 12 301 3 2 2 21.01 21.31 8.31 2.176 1.077 0.601 0.31007 0.33211 0.30811 1.86 1.75 1.15 13 101 1 2 2 15.12 19.83 5.32 2.171 1.206 1.011 0.35813 0.31720 0.35557 5.12 1.97 5.11 11 102 1 2 1 11.19 19.10 8.20 2.293 1.261 1.073 0.10151 0.38192 0.36780 5.71 5.18 5.31 15 103 1 1 2 13.52 17.21 3.91 2.825 1.171 1.127 0.53116 0.53190 0.18359 6.62 8.59 5.99 1 1 1 10.58 17.17 7.86 2.171 1.506 0.862 0.19791 0.19715 0.16109. 8.17 8.16 5.71 1 0.57 0.12 0.16 1.16 2 0.99 0.55 0.19 1.73 3 0.51 0.19 0.23 1.25 1 0.69 0.29 0.15 1.11 5 0.50 0.25 0.07 0.82 6 0.78 0.83 0.07 1.16 7 0.15 0.38 0.10 0.91 8 0.59 0.36 0.07 1.02 9 0.16 0.21 0.06 0.78 10 0.88 0 15 0.20 1.51 11 0.91 0 12 0.06 1.39 12 0.78 0 31 0.09 1.21 13 0.81 0 37 0.08 1.06 11 0.18 0 11 0.11 0.97 15 0.78 0 51 0.08 1.37 16 0.19 0 19 0.12 1.10 APPENDIX B APPENDIX B Recovery of Fertilizer-15N -- Data and Calculations Four microplots identical to those which recieved alfalfa—15N were established at both EL and KBS on areas adjacent to the alfalfa—15N microplots but where corn had been the previous crop. K15N03 ferilizer (23.8 atom % excess) was applied to the surface of these microplots in Spring, 1986 at a rate equivalent to 112 kg N ha'1 and incorporated to a 5 cm depth. Corn was planted, harvested, and along with sampled soil, analyzed for N and 15N -- all according to methods described in the Materials and MethodS' section for microplots that recieved alfalfa-15N. Results are presented in raw data form in the following tables. 1. Table Bl Recovery of ferilizer 15N by corn grain, stover and roots was calculated by equations similar those described in Appendix A. For example: V12 = V3 x V6/100 x V9 / 0.7756896 Where: 0.7756896 = 3.2592 x 23.8/100 3.2592 g of fertilizer-N applied 2.3 = 15N atom % excess of fertilizer V15 : V12 + V13 + V14 58 59 2. Table B2 Recovery of fertilizer-15N in total N soil fraction was also calculated by equations similar to those in Appendix A. For example: V15 = V3 x V7/100 x V11 / 0.7756896 V19 = V15 + V16 + V17 + V19 3. Table B3 Recovery of fertilizer-15N in the inorganic soil N fraction was also calculated by equations similar to those in Appendix A. For example: V15 2 V3 x V7 X V11 / 775689.6 V19 = V15 + V16 + V17 + V19 4. Table B4 Microbial biomass C was calculated by Cf/O 41 as described in the Materials and Methods section. 5. Table B5 Microbial Biomass N was calculated as in Appendix A and described in the Materials and Methods section. Recovery of fertilizer-15N in microbial biomass was calculated as follows: V15 = V3 x V13 x V14 / 775689.6 650 Table 81. Corn dry natter yield, I content and recovery of fertilizer I-15 by corn at It and [88. 1157 07 VIRIIBLIS TTPI IIIR/DRSCRIPTIOI nuneric location 1:81 2:186 nuneric Plot 8 nuneric Grain 0.8. Tield (g/plot) nuneric Stover 0.8. Tield (g/plot) nuneric Root 0.8. Tield (g/plot) nuneric II Grain nuneric II Stover nuneric II Roots nuneric I-15 1ton I Rxcess Grain nuneric I-15 1ton I Rxcess Stover nuneric I-15 1ton I Rxcess Roots nuneric Recovery of Fertilizer I-15 by Grain (I of input) nuneric Recovery of Fertilizer l-15 by Stover (I of input) nuneric Recovery of Fertilizer l-15 by Roots (I of input) nuneric Recovery by Corn - GraintStovertRoots (I of input) 1 2 3 1 5 8 7 8 9 10 11 12 13 1 1 268.3 207.6 20.1 1.13 0.51 L 13 0.13870 L 53280 0. 88710 1. 70 0. 73 1 2 333.7 288.6 30.6 1.20 0.11 0.10 8.11800 5. 73020 1. 22180 33.13 8. 73 1 3 178.8 211.1 22.0 1.21 0.55 0.18 6.17220 1. 99510 1. 21700 17.85 7. 58 1 1 133.3 311.2 17.8 1.22 0. 51 L 19 1. 08560 1.21390 3. 73300 27.71 10. 08 2 1 213.8 160.0 11.8 0.72 L 88 0. 52 1. 38760 0. 98170 L 77110 2 75 L 71 2 2 179.1 159.0 17.1 0.91 0.57 L 17 0.15587 0. 31000 0.28590 0. 99 0. 36 2 3 217.8 153.0 12.9 0.88 0.51 L 11 0.17850 0.13280 0. 35010 1.18 0.11 2 1 311.3 230.0 21.3 1.00 0. 51 L 19 L 73130 1.11770 0. 71770 6. 95 L 32 631 Table 82. Recovery of fertilizer l-15 in total soil 8 at 81 and [88. d b- n DISCRIPTIOI Location 1:71 2:186 Plot 8 0-15 Total Layer 0.8. (3) 15-38 Total Layer 0.7. (x) 30-15 Total Layer 0.8. (x) 15-60 Total layer 0.I. (3) 0-15 Total I (II) 15-30 Total I (II) 30-15 Total I (II) 15-80 Total I (II) ecu-damuuuNI-n H 1 1 1 56800 58200 67500 30800 2 1 2 55000 58800 68500 80100 3 1 3 51900 55100 53900 52100 1 1 1 19500 62600 58800 56700 5 2 1 19600 58900 72800 59800 8 2 2 18000 51800 66300 51100 7 2 3 18600 69500 71300 67500 8 2 1 37700 59900 50000 55900 18 17 18 19 1 0 18 0.23 0.35 1.82 2 1 16 1.21 0.78 5.99 3 1 07 0.51 0.52 6.15 1 1 17 0.55 0.21 1.91 5 0 38 0.13 0.31 1.75 8 0 71 0.07 0.18 1.27 7 0 52 0.09 0.07 0.93 8 1 03 0.38 0.51 2.31 DESCRIPTIOI 0-15 Total I I-15 1ton I Rxcess 15-30 Total I I-15 1ton I Rxcess 30-15 Total I I-15 Iton I Rxcess 15-80 Total I I-15 1ton I Excess Recovery of fert. l-15 in 0-15 (I of input) Recovery of fert. I-15 in 15-30 (I of input) Recovery of fert. I-15 in 30-15 (I of input) Recovery of fert. I-15 in 15-60 (I of input) Recovery of fert. I-15 in 0-80 (I of input) 9 10 11 12 13 11 15 .00837 0. 00711 0. 01331 0. 01137 0 .03579 0. 03211 0. 01880 0.01880 2 .01730 0. 01192 0. 01951 0. 02590 1 .02781 0. 02027 0. 02111 0.01811 2. .00889 0. 00632 0. 02276 0. 02015 0 .00561 0. 01250 0. 00820 0. 01111 0 .00155 0. 00822 0. 00975 0. 00818 0 .00533 0. 01023 0. 00851 0. 01788 0 uhp—oNNNuNN 9:699:66 6L2 Table 83. Recovery of fertilizer I-15 in inorganic soil I at El and IRS. 1187 07 TIRIIIIIS IIR cmoqam-uN—- .— 1 1 56800 58200 67500 30800 1. 1 2 55000 58800 86500 60100 1. 1 3 51900 55100 53900 52100 2. 1 1 19500 62600 58800 56700 1. 2 1 19600 58900 72800 59800 2. 2 2 2 DISCRIPTIOI location 1=Il 2:“ Plot 8 0-15 Total layer 0.I. (g) 15-30 Total layer 8.8. (g) 30-15 Total layer R.I. (g) 15-60 Total layer R.I. (g) 0-15 Inorganic I (ug/g) 15-30 Inorganic l (ug/g) 30-15 Inorganic I (ug/g) 15-60 Inorganic I (ug/g) 2 16000 51800 86300 51100 2. 3 18600 69500 71300 67500 1. 1 37700 59900 50000 55900 3. oueufneuhr— DESCRIPTIOI 0-15 Inorganic I I-15 Itoa I Excess 15-30 Inorganic I I-15 1ton I Excess 30-15 Inorganic I I-15 1ton I Excess 15-60 Inorganic I l-15 1ton I Excess 0-15 Inorganic I-15 Recovery (I of input) 15-30 Inorganic I-15 Recovery (I of input) 30-15 Inorganic I-15 Recovery (I of input) 15-60 Inorganic I-15 Recovery (I of input) 0-80 Inorganic I-15 Recovery (I of input) 5.8 8. 5 0. 07380 0. 05217 0. 02399 0. 01382 0.1 5.8 2. 8 0. 20293 0.15083 0.11506 0 11581 0.2 5.6 2. 5 0. 29190 0.13888 0.15579 0. 07180 0.1 6.3 1. 2 0.15181 0.12010 0. 05131 0. 01110 0.1 7.1 10.2 0. 03312 0. 01631 0. 01008 0. 00618 0.0 5.0 6. 7 0. 02786 0. 01181 0 00698 0. 00162 0.0 7.1 5. 7 0. 02895 0. 05623 0. 00733 0. 00210 0.0 11.3 9.1 0. 05382 0. 23855 0. 03701 0. 03572 0.1 63 Table B4. Microbial biomass carbon at EL and KBS. LIST OF VARIABLES VAR TYPE NAME/DESCRIPTION 1 numeric Location 1=EL 2=KBS 2 numeric Plot # . 3 numeric Carbon Flush for Fumigation/lO day Incubation - Cf (ug/g) 4 numeric Carbon Evolved for Unfumigated 10 day Incubation - C10 (ug/g) 5 numeric Carbon Evolved for Unfumigated 20 Incubation - C20 (ug/g) 6 numeric Microbial Biomass Carbon - Cf/0.41 (ug/g) CASE NO 1 2 3 4 5 6 1 1 1 125.1 49.7 55.7 305.2 2 1 2 136.0 56.6 47.4 331.7 3 1 3 144.8 82.9 68.3 353.3 4 1 4 145.1 63.1 51.4 354.0 5 2 1 70.3 54.6 42.9 171.4 6 2 2 70.3 54.6 22.3 171.4 7 2 3 38.0 28.9 3.4 92.7 8 2 4 102.3 80.0 35.1 249.5 Table lIST TIR cadamfiunp £34 85. Iicrobial bionass I and recovery of fertilizer I-15 in nicrobial bionass at El and 188. 07 VIRIIRLRS IIIE/DISCRIPTIOI location 1:11 2=I86 Plot 8 0-15 Total layer 0.8. (g) Initial I03 Concentration (ppn) Initial I81 Concentration (ppn) Tunigated/io day Incubation I03 Concentration (ppn) Tunigated/lo day Incubation II1 Concentration (ppn) 0nfunigated/20 day Incubation I03 Concentration (ppn) 0nfunigated/20 day Incubation I81 Concentration (ppn) litrogen Elusb - If (ug/g) Carbon Elusb - Cf (ug/g) In - -0.011(Cf/lf) + 0.39 Iicrobial Bionass I - If/In (ug/g) 7unigated/10 day Incubation Inorganic I I-15 1ton I Excess Recovery of fert. I-15 in Iicrobial Bionass (I of input) 1 2 3 1 5 8 7 8 9 10 11 12 13 1 1 58800 1. 28 0. 00 1.30 1.75 3.57 0.00 8.75 125.1 0.190 16.1 1 2 55000 1.11 0.00 1.18 2.15 3.73 0.00 10.75 138.0 0.213 50.5 1 3 51900 2.08 0.00 1.99 2.65 1.75 0.00 13.25 111.8 0.237 55.9 1 1 19500 2.00 0.00 1.50 2.19 1.79 0.00 12.15 115.1 0.227 51.9 2 1 19800 1.82 0.00 1.75 1.86 1.05 0.00 9.10 70.3 0.285 32.9 2 2 16000 1. 15 0. 00 1.10 1.31 3.37 0.00 8.70 70.3 0.213 27.6 2 3 16600 1. 33 0. 00 1.21 1.16 2.92 0.00 5.80 38.0 0.298 19.1 2 1 37700 2. 38 0. 00 2.25 2.30 1.18 0.00 11.50 102.3 0.265 13.3 666650-39: c o o o c c o o Hccemmcu _.uo'v@¢oovce APPENDIX C APPENDIX C N Fertilizer Replacement Value of Alfalfa An experiment was conducted on areas adjacent to the microplots which recieved 15N fertilizer at EL and KBS, previously cropped to corn, to determine the N fertilizer replacement value of alfalfa. The experimental design was a randomized complete block with 4 replications. NHaNOa fertilizer was broadcast on corn plots at rates of 0, 56, 112, 168, and 224 kg N ha"1 after planting in the Spring, 1986. Each plot consisted of 4, 6.10 m rows planted on 76.2 cm row spacings at a population of 59 000 plants ha'l. Four plots of the same size were also established at each site on areas adjacent to the microplots which recieved alfalfa- 15N (on ground previously cropped to alfalfa). Corn grain and stover (stalks + cobs) were harvested from the center 2 rows of each plot after the corn reached physiological maturity in the fall. Grain and stover fresh weights were recorded for each plot and samples were taken to determine d.m. percentage. Grain and stover d.m. yields —- V16 and V17, respectively -- in Tables Cl and CZ were calculated by multiplying plot fresh weight times sample dry weight divided by sample fresh weight, divided by plot area. For example: 65 66 V16 = V7 x V9/V8 / 2.2 / 0.00931 Where: 2.2 = conversion from lbs to kg 0.00931 2 plot size in ha. A 2-way analysis of variance (replication x N rate) was performed on grain yield (V16) for each location and results indicated there was no N response at either location. Therefore, a N fertilizer replacement value could not be determined for either site. 857 Table 01. I fertiliser replacenent value data at El. lIST 07 718118185 718 10340001.puNn—o nuneric nuneric nuneric nuneric nuneric nuneric nuneric nuneric nuneric nuneric nuneric nuneric nuneric nuneric nuneric nuneric p... N IIII/DESCRIPTIOI Plot 8 Replication l Rate (kg/bu) 1:8 n/alfalfa 2:0 3:58 1:112 5:188 8:221 8 plants harvested/plot (plot 2 2 30' rovs x 20') I ears harvested/plot Grain and out 1.8. (lbs/plot) Grain R.I. (lbs/plot) Sanple grain 7.8. (g) Sanple grain 0.I. (g) Sanple cob 7.8. (g) Sanple cob 0.8. (g) Stover 7.8. (lbs/plot) Sanple stover 8.8. (g) Sanple stover 0.8. (g) Crain noisture (I) Grain yield (kg/b 0.8.) Stover yield (kg/8 0.8.) u e c ----.~.~uuuuuu---ww~H—M 3 1 5 8 7 8 9 10 11 12 13 11 15 18 17 1 55 60 36 28. 9 500 317. 3 237.1 132.1 12.8 2023 598 30. 5 9801 6177 5 52 79 37 29.6 500 319. 0 219.1 118.8 18.1 1782 515 30. 2 10067 6505 3 10 58 27 21. 7 500 313. 2 208.5 95. 0 38. 1 2110 683 31. 1 7272 1995 2 11 53 29 22.7 500 311.1 211.9 121. 9 38. 7 1892 556 31.7 7567 5553 6 19 87 31 27.1 500 353. 7 220. 6 110. 0 16.8 1912 539 29.3 9163 8111 1 55 88 35 27. 5 500 351.1 221.8 118.9 18. 5 2198 687 29.7 9136 7186 1 57 58 35 27.8 500 311.0 221.7 111.2 12. 7 1818 526 31.2 9338 5910 1 17 77 36 28. 9 500 352. 5 183. 3 81.9 11. 8 2127 617 29.5 9918 8178 2 39 57 29 22.8 500 312. 0 232.5 113.3 37.0 2061 563 31.6 7517 1928 8 11 53 30 23.6 500 318. 7 201.7 101.9 12. 5 1861 579 30. 3 8038 6156 5 19 53 31 21.1 500 353.5 253.8 131.1 12.8 2058 589 29.3 8122 5958 3 51 59 30 21.1 500 357. 0 200. 9 102.5 12.1 1938 590 28.6 8101 8261 1 50 52 32 25.1 500 318.0 208.1 98. 2 10. 0 1861 567 30. 8 8180 5911 8 17 83 31 28. 9 500 357.7 212.9 111.1 39.8 1970 577 28.5 9396 5663 5 12 55 31 21. 3 500 311.9 213.2 108.8 39. 1 2126 801 31.0 8181 5138 1 15 58 31 26.6 500 317.0 188.5 80. 8 17.5 1820 530 30. 6 9013 6753 3 51 59 31 26.5 500 311.8 235. 5 128. 7 51.1 2182 851 31.0 8922 7522 2 17 87 37 29.0 500 351.5 232.8 118.3 18. 1 2269 896 29.7 9951 8901 1 18 53 31 28.7 500 350. 6 201.1 108.5 38.1 1932 572 29.9 9111 5507 1 51 77 11 33.3 500 319.8 218.9 110. 6 53. 6 2168 633 30. 0 11371 7669 2 19 65 31 27.1 500 317.3 197.1 102.5 11. 1 2831 896 30. 5 9292 1989 5 15 66 38 28. 9 500 319.6 209.2 111. 3 11.5 1702 510 30.1 9886 8893 6 11 82 35 27.7 500 313.0 239. 5 121.7 13.8 2517 711 31. 1 9278 5912 3 16 68 38 30.1 500 350.1 201.1 101.1 19.7 2121 727 30. 0 10393 7287 638 Table C2. I fertiliser replacenent value data at 788. 1187 07 718118176 718 7788 IIIE/DESCRIPTIOI 1 nuneric Plot 8 2 nuneric Replication 3 nuneric I Rate (kg/Ia) 1:0 vitb alfalfa 2:0 3:58 1:112 5:188 6:221 1 nuneric 8 plants harvested/plot (plot = 2 30' rows x 20') 5 nuneric 1 ears harvested/plot 6 nuneric Grain and cob 7.8. (lbs/plot) 7 nuneric Grain 7.8. (lbs/plot) 8 nuneric Sanple grain 7.8. (g) 9 nuneric Sanple grain 8.8. (g) 10 nuneric Sanple cob 7.8. (g) 11 nuneric Sanple cob 0.8. (g) 12 nuneric Stover 7.8. (lbs/plot) 13 nuneric Sanple stover 7.8. (g) 11 nuneric Sanple stover 0.8. (g) 15 nuneric Grain noisture (I) 16 nuneric Grain Yield (kg/ha 0.8.) 17 nuneric Stover Tield (kg/ha 0.8.) CISE 80.1231567691011121311151817 1 100 1 1 63 73 31 28.2 500 381.5 189.6 103.3 16. 6 1668 511 23. 1 10588 7379 2 101 1 2 62 80 10 32.8 500 382.8 186.7 100.3 15.6 1699 536 27.1 11620 6281 3 102 1 5 57 81 39 31.9 500 369.8 189.1 92.2 52. 5 2036 587 2L 0 11519 7390 1 103 l 6 85 93 13 31.8 500 363.7 168.0 91.8 53.1 2212 810 27.3 12359 7501 5 101 1 3 61 91 10 33.1 500 376.1 188.3 111.0 51. 9 1872 529 2L 8 12156 7161 6 105 1 1 55 100 18 38.2 500 370.1 162.8 81.2 53.2 1991 806 25.9 13816 7908 7 200 2 1 56 69 38 29.5 500 372.6 188.0 109.7 13.5 1515 172 25.5 10733 8617 8 201 2 1 56 98 15 36.9 500 362.5 185.5 99.8 51.3 1678 182 27. 5 13061 7203 9 202 2 2 63 87 11 33.8 500 361.1 191.8 92.1 16.9 1615 169 27.1 11958 6528 10 203 2 6 63 98 15 38.9 500 381.0 198.2 102.5 53.1 1888 181 27.2 13118 7387 11 201 2 3 60 91 15 38.1 500 362.5 233.1 125.9 19.5 2119 585 27. 5 12778 6672 12 205 2 5 18 83 37 30.8 172 319.6 211.1 105.5 13.0 2000 593 2L 9 11066 6225 13 300 3 1 57 73 33 28.2 500 377.9 169.5 91.3 12.2 1769 521 21. 1 10106 8103 11 301 3 5 82 98 17 39.0 500 383.1 177.0 93.8 18. 5 1809 530 27.3 13839 8938 15 302 3 6 56 92 13 35.9 500 373.1 172.8 91.2 52.1 1789 557 25.1 13079 7920 16 303 3 2 66 80 13 35.3 500 363.1 191.5 105.8 16.5 1628 160 27.1 12516 6115 17 301 3 3 88 103 17 38.7 500 371.5 161.1 87.7 19.3 1585 177 25.1 11152 7211 18 305 3 1 88 100 18 39.1 500 372.8 177.1 91.8 19.7 1831 513 25.1 11313 7181 19 100 1 1 81 82 13 26.8 500 378.2 191.1 107.6 39.3 1171 183 21. 1 9823 8287 20 101 1 5 56 95 15 38.6 500 368.1 139.0 73.1 52.1 2105 583 28.3 13186 7015 21 102 1 3 82 101 19 10.1 500 368.5 186.8 99.3 53.5 2071 599 28.3 11537 7511 22 103 1 1 85 95 17 38.5 500 370.5 177.0 95.9 55.1 1995 532 25.9 13929 7213 23 101 1 6 58 102 15 37.3 500 373.1 163.5 99.0 51.0 1902 537 25.3 13600 7030 21 105 1 2 59 98 51 11.8 500 378.2 168.5 92.7 18.8 2177 625 21. 1 15137 6810 "10188800188803