气候变化领域集成服务门户(CCPortal): Outsized nutrient contributions from small tributaries to a Great Lake

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DOI	10.1073/pnas.2001376117
	Outsized nutrient contributions from small tributaries to a Great Lake
	Mooney R.J.; Stanley E.H.; Rosenthal W.C.; Esselman P.C.; Kendall A.D.; McIntyre P.B.
发表日期	2020
ISSN	0027-8424
起始页码	28175
结束页码	28182
卷号	117 期号:45
英文摘要	Excessive nitrogen (N) and phosphorus (P) loading is one of the greatest threats to aquatic ecosystems in the Anthropocene, causing eutrophication of rivers, lakes, and marine coastlines worldwide. For lakes across the United States, eutrophication is driven largely by nonpoint nutrient sources from tributaries that drain surrounding watersheds. Decades of monitoring and regulatory efforts have paid little attention to small tributaries of large water bodies, despite their ubiquity and potential local importance. We used a snapshot of nutrient inputs from nearly all tributaries of Lake Michigan—the world’s fifth largest freshwater lake by volume—to determine how land cover and dams alter nutrient inputs across watershed sizes. Loads, concentrations, stoichiometry (N:P), and bioavailability (percentage dissolved inorganic nutrients) varied by orders of magnitude among tributaries, creating a mosaic of coastal nutrient inputs. The 6 largest of 235 tributaries accounted for ∼70% of the daily N and P delivered to Lake Michigan. However, small tributaries exhibited nutrient loads that were high for their size and biased toward dissolved inorganic forms. Higher bioavailability of nutrients from small watersheds suggests greater potential to fuel algal blooms in coastal areas, especially given the likelihood that their plumes become trapped and then overlap in the nearshore zone. Our findings reveal an underappreciated role that small streams may play in driving coastal eutrophication in large water bodies. Although they represent only a modest proportion of lake-wide loads, expanding nutrient management efforts to address smaller watersheds could reduce the ecological impacts of nutrient loading on valuable nearshore ecosystems. © 2020 National Academy of Sciences. All rights reserved.
英文关键词	Tributary \| nutrient loads \| Laurentian Great Lakes \| eutrophication
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/160740
作者单位	Mooney, R.J., Center for Limnology, University of Wisconsin–Madison, Madison, WI 53706, United States; Stanley, E.H., Center for Limnology, University of Wisconsin–Madison, Madison, WI 53706, United States; Rosenthal, W.C., Center for Limnology, University of Wisconsin–Madison, Madison, WI 53706, United States, Department of Botany, University of Wyoming, Laramie, WY 82071, United States; Esselman, P.C., Great Lakes Science Center, US Geological Survey, Ann Arbor, MI 48105, United States; Kendall, A.D., Department of Earth and Environmental Sciences, Michigan State University, East Lansing, MI 48824, United States; McIntyre, P.B., Center for Limnology, University of Wisconsin–Madison, Madison, WI 53706, United States, Department of Natural Resources, Cornell University, Ithaca, NY 14853, United States
推荐引用方式 GB/T 7714	Mooney R.J.,Stanley E.H.,Rosenthal W.C.,et al. Outsized nutrient contributions from small tributaries to a Great Lake[J],2020,117(45).
APA	Mooney R.J.,Stanley E.H.,Rosenthal W.C.,Esselman P.C.,Kendall A.D.,&McIntyre P.B..(2020).Outsized nutrient contributions from small tributaries to a Great Lake.Proceedings of the National Academy of Sciences of the United States of America,117(45).
MLA	Mooney R.J.,et al."Outsized nutrient contributions from small tributaries to a Great Lake".Proceedings of the National Academy of Sciences of the United States of America 117.45(2020).