Submitted to: ASA-CSSA-SSSA Annual Meeting Abstracts
Publication Type: Abstract only
Publication Acceptance Date: 7/9/2004
Publication Date: 10/25/2004
Citation: Sainju, U.M., Terrill, T.H., Gelaye, S., Singh, B.P. 2004. Seasonal variation in rhizoma peanut and perennial weeds biomass and soil carbon and nitrogen pools [abstract]. American Society of Agronomy, Crop Science Society of America, Soil Science Society of America. Paper No. 3397. Interpretive Summary:
Technical Abstract: Short- and long-term productivity of rhizoma peanut [(Arachis glabrata Benth.), a warm-season perennial legume forage] may improve soil quality and fertility by increasing organic matter and N mineralization compared with perennial weeds. We examined seasonal and long-term effects of biomass yield, N accumulation, and root length density from 0 to 70 cm depth of 10-yr-old rhizoma peanut and perennial weeds [dominated by henbit (Lamium amplexicaule L.) and cut-leaf evening primrose (Oenothera laciniata L.)] on soil organic C, total N, NH4-N, NO3-N, potential C and N mineralization (PCM and PNM), microbial biomass C and N (MBC and MBN), and particulate organic C and N (POC and PON) from June to October, 2000 and 2001. Field plots were established on a Norfolk loamy fine sand (fine-loamy, siliceous, thermic Typic Kandiudults) in April 1991 in central Georgia. Biomass yield and N accumulation in peanut and weeds increased from June to October, 2000 and 2001, and were greater in peanut than in weeds from July to October. Root length density increased from June to September and was greater in peanut than in weeds in September. Soil total N in June, July, and October 2000 and July 2001, POC in June, July, and October 2000 and from July to September 2001, PON in June and October 2000 and July 2001, MBC in July and September 2001, MBN in August to October 2000 and August to September 2001, PCM in July 2001, PNM in September 2001, NH4-N in June and October 2000, and NO3-N in August 2000 and September 2001 were greater under peanut than under weeds. Like plant biomass, C and N pools did not vary linearly with sampling date, except NH4- and NO3-N. Regardless of dates, organic C, total N, POC, PON, MBC, MBN, PCM, PNM, and NO3-N were greater under peanut than under weeds. Short-term productivity of rhizoma peanut may enrich soil N availability while long-term productivity may improve soil quality and productivity by increasing microbial activities, N mineralization, and C and N sequestration compared with perennial weeds.