气候变化领域集成服务门户(CCPortal): N2O Emissions From Residues of Oat and Grass Pea Cover Crops Cultivated in the US Southern Great Plains

CCPortal

DOI	10.3389/fsufs.2020.604934
	N2O Emissions From Residues of Oat and Grass Pea Cover Crops Cultivated in the US Southern Great Plains
	Singh H.; Kandel T.P.; Gowda P.H.; Northup B.K.; Kakani V.G.
发表日期	2021
ISSN	2571581X
卷号	4
英文摘要	Grass pea (Lathyrus sphaericus) and oat (Avena sativa) are potential cover crops for spring periods of summer crop systems in the US Southern Great Plains (SGP). The main objective of this study was to compare nitrous oxide (N2O) emissions from residues of grass pea and oat grown as green nitrogen (N) crops. The comparisons included responses from plots cultivated with oat, grass pea, and control (spring-fallowed) plots. Two management options were applied to grass pea: residues retained and aboveground biomass removed for forage. Crabgrass (Digitaria sanguinalis) was cultivated as a main summer crop immediately after termination of the cover crops. Fluxes of N2O were measured by closed chamber connected to a portable gas analyzer on 23 dates during a 3 month growing period for crabgrass. At termination, oat produced more aboveground biomass than grass pea (2.17 vs. 3.56 Mg ha−1), but total N in biomass was similar (102–104 kg ha−1) due to greater N concentrations in grass pea than oat (4.80% vs. 2.86% of dry mass). Three month cumulative emissions of N2O from grass pea-incorporated plots (0.76 ± 0.11 kg N2O-N ha−1; mean ± standard error, n = 3) were significantly lower than from oat-incorporated plots (1.26 ± 0.14 kg N2O-N ha−1). Emissions from grass pea plots with harvested biomass (0.48 ± 0.04 kg N2O-N ha−1) were significantly lower than those from grass pea-incorporated plots. Cumulative N2O emissions from control plots were significantly greater than those from grass pea-harvested plots but were similar to the emissions from grass pea-incorporated plots. Yields produced by crabgrass were similar from all cover crop treatments (8.65–10.46 Mg ha−1), but yield responses to the control (18.53 Mg ha−1) were significantly larger. Nitrogen concentrations in crabgrass were greater in response to oat- and grass pea-incorporated plots (2.86–2.87%) than in grass pea-harvested (1.93%) and control (1.44%) plots. In conclusion, the results indicated that (i) post-incorporation emissions of N2O can be greater from a non-legume green N crop than a legume green N crop due to greater biomass productivity of the cereal, and (ii) emissions of N2O could be mitigated by removing biomass of the green N crop for use as forage. © Copyright © 2021 Singh, Kandel, Gowda, Northup and Kakani.
英文关键词	biomass decomposition; cover crop; crabgrass; forage; nitrogen mineralization; residue
来源期刊	Frontiers in Sustainable Food Systems
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/177245
作者单位	Department of Plant and Soil Sciences, Oklahoma State University, Stillwater, OK, United States; Noble Research Institute, LLC, Ardmore, OK, United States; United States Department of Agriculture-Agricultural Research Service Southeast Area, Stoneville, MS, United States; United States Department of Agriculture-Agricultural Research Service Grazinglands Research Laboratory, El Reno, OK, United States
推荐引用方式 GB/T 7714	Singh H.,Kandel T.P.,Gowda P.H.,et al. N2O Emissions From Residues of Oat and Grass Pea Cover Crops Cultivated in the US Southern Great Plains[J],2021,4.
APA	Singh H.,Kandel T.P.,Gowda P.H.,Northup B.K.,&Kakani V.G..(2021).N2O Emissions From Residues of Oat and Grass Pea Cover Crops Cultivated in the US Southern Great Plains.Frontiers in Sustainable Food Systems,4.
MLA	Singh H.,et al."N2O Emissions From Residues of Oat and Grass Pea Cover Crops Cultivated in the US Southern Great Plains".Frontiers in Sustainable Food Systems 4(2021).