HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Abstract Full Text Free Full Text (PDF) Free Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in Web of Science Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Web of Science (6) Citing Articles via Google Scholar Google Scholar Articles by Gil, J. L. Articles by Fick, W. H. Search for Related Content PubMed Articles by Gil, J. L. Articles by Fick, W. H. Agricola Articles by Gil, J. L. Articles by Fick, W. H. Related Collections Intercropping Systems Alfalfa Clover Other Forage Crops Nutrient Cycling Soil Fertility and Productivity

Soil Nitrogen Mineralization in Mixtures of Eastern Gamagrass with Alfalfa and Red Clover

^a Instituto Nacional de Investigaciones Agrícolas (INIA), CENIAP, Instituto de Investigaciones Zootécnicas, Apartado 4653, Maracay 2101, Aragua, Venezuela
^b Dep. of Agron., Throckmorton Hall, Kansas State Univ., Manhattan, KS 66506-5501

View larger version (34K): [in a new window]   Fig. 1. Daily maximum and minimum air temperature and precipitation recorded at Manhattan, KS during the 1996 growing period.

View larger version (35K): [in a new window]   Fig. 2. Daily maximum and minimum air temperature and precipitation recorded at Manhattan, KS during the 1997 growing period.

View larger version (38K): [in a new window]   Fig. 3. Total inorganic N at Manhattan and Plant Materials Center (PMC) in soils under eastern gamagrass (EGG), alfalfa (ALF), red clover (RC), and their mixtures for two consecutive years. LSD lines indicate significant differences (P < 0.05) among treatments in the same day. Arrows indicate harvest date as follows for 1996: (a) first cut of all treatments; (b) Second cut of alfalfa; (c) second cut of EGG–ALF mixture; (d) third cut of alfalfa; (e) second cut of RC, EGG–RC mixture, and EGG; (f) third cut of EGG–ALF mixture; and (g) fourth cut of alfalfa. For 1997: Same sequence, except for (f) third cut of EGG–ALF mixture and fourth of alfalfa.

View larger version (23K): [in a new window]   Fig. 4. Total annual net N mineralization at Manhattan and Plant Materials Center (PMC) in soils under eastern gamagrass (EGG), alfalfa, red clover, and their mixtures for two consecutive years. Different letters indicate significant differences (P < 0.05) among treatment means at the same location.

View larger version (35K): [in a new window]   Fig. 5. Net N mineralization at Manhattan and at Plant Materials Center (PMC) in soils under eastern gamagrass (EGG), alfalfa, red clover (RC), and their mixtures for two consecutive years. LSD lines indicate significant differences (P < 0.05) among treatment means at the same incubation period. Abbreviations for incubation periods are the first letter of each month, starting with April (A). Arrows indicate harvest date as follows: (a) first cut of all treatments; (b) second cut of alfalfa and EGG–alfalfa mixture; (c) third cut of alfalfa and second cut of EGG, RC, and EGG–RC mixture; (d) fourth cut of alfalfa and third cut of EGG–alfalfa mixture.

View larger version (21K): [in a new window]   Fig. 6. Relationship between total annual net N mineralization and C/N ratio for 1997 at Manhattan and at Plant Materials Center (PMC) in soils under eastern gamagrass (EGG), alfalfa, red clover (RC), and their mixtures. Equations are in the text.

View larger version (25K): [in a new window]   Fig. 7. Relationship between total annual net N mineralization and biomass production at Manhattan and at Plant Materials Center (PMC) in soils under eastern gamagrass, alfalfa, red clover, and their mixtures in 1996 and 1997. (A) Regression analysis per location and all data considered together, (B) regression analysis for Manhattan in 1996 and 1997, and (C) regression analysis for PMC in 1996 and 1997.