气候变化领域集成服务门户(CCPortal): The extent of soil loss across the US Corn Belt

CCPortal

DOI	10.1073/pnas.1922375118
	The extent of soil loss across the US Corn Belt
	Thaler E.A.; Larsen I.J.; Yu Q.
发表日期	2021
ISSN	00278424
卷号	118 期号:8
英文摘要	Soil erosion in agricultural landscapes reduces crop yields, leads to loss of ecosystem services, and influences the global carbon cycle. Despite decades of soil erosion research, the magnitude of historical soil loss remains poorly quantified across large agricultural regions because preagricultural soil data are rare, and it is challenging to extrapolate local-scale erosion observations across time and space. Here we focus on the Corn Belt of the midwestern United States and use a remote-sensing method to map areas in agricultural fields that have no remaining organic carbon-rich A-horizon. We use satellite and LiDAR data to develop a relationship between A-horizon loss and topographic curvature and then use topographic data to scale-up soil loss predictions across 3.9 × 105 km2 of the Corn Belt. Our results indicate that 35 ± 11% of the cultivated area has lost A-horizon soil and that prior estimates of soil degradation from soil survey-based methods have significantly underestimated A-horizon soil loss. Convex hilltops throughout the region are often completely denuded of A-horizon soil. The association between soil loss and convex topography indicates that tillage-induced erosion is an important driver of soil loss, yet tillage erosion is not simulated in models used to assess nationwide soil loss trends in the United States. We estimate that A-horizon loss decreases crop yields by 6 ± 2%, causing $2.8 ± $0.9 billion in annual economic losses. Regionally, we estimate 1.4 ± 0.5 Pg of carbon have been removed from hillslopes by erosion of the A-horizon, much of which likely remains buried in depositional areas within the fields. © 2021 National Academy of Sciences. All rights reserved.
英文关键词	Agricultural productivity; Remote sensing; Soil erosion; Soil organic carbon
语种	英语
来源期刊	Proceedings of the National Academy of Sciences of the United States of America
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/180513
作者单位	Department of Geosciences, University of Massachusetts, Amherst, MA 01003, United States
推荐引用方式 GB/T 7714	Thaler E.A.,Larsen I.J.,Yu Q.. The extent of soil loss across the US Corn Belt[J],2021,118(8).
APA	Thaler E.A.,Larsen I.J.,&Yu Q..(2021).The extent of soil loss across the US Corn Belt.Proceedings of the National Academy of Sciences of the United States of America,118(8).
MLA	Thaler E.A.,et al."The extent of soil loss across the US Corn Belt".Proceedings of the National Academy of Sciences of the United States of America 118.8(2021).