Dataset Information

Key components and contrasts in the nitrogen budget across a US-Canadian transboundary watershed.

ABSTRACT: Watershed nitrogen (N) budgets provide insights into drivers and solutions for groundwater and surface water N contamination. We constructed a comprehensive N budget for the transboundary Nooksack River Watershed (British Columbia, Canada and Washington, US) using locally-derived data, national statistics and standard parameters. Feed imports for dairy (mainly in the US) and poultry (mainly in Canada) accounted for 30 and 29% of the total N input to the watershed, respectively. Synthetic fertilizer was the next largest source contributing 21% of inputs. Food imports for humans and pets together accounted for 9% of total inputs, lower than atmospheric deposition (10%). N imported by returning salmon representing marine derived nutrients accounted for <0.06 % of total N input. Quantified N export was 80% of total N input, driven by ammonia emission (32% of exports). Animal product export was the second largest output of N (31%) as milk and cattle in the US and poultry products in Canada. Riverine export of N was estimated at 28% of total N export. The commonly used crop nitrogen use efficiency (NUE) metric alone did not provide sufficient information on farming activities but in combination with other criteria such as farm-gate NUE may better represent management efficiency. Agriculture was the primary driver of N inputs to the environment as a result of its regional importance; the N budget information can inform management to minimize N losses. The N budget provides key information for stakeholders across sectors and borders to create environmentally and economically viable and effective solutions.

SUBMITTER: Lin J

PROVIDER: S-EPMC8318187 | biostudies-literature | 2020 Sep

REPOSITORIES: biostudies-literature

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Key components and contrasts in the nitrogen budget across a US-Canadian transboundary watershed.

Lin Jiajia J Compton Jana E JE Clark Chris C Bittman Shabtai S Schwede Donna D Homann Peter S PS Kiffney Peter P Hooper David D Bahr Gary G Baron Jill S JS

Journal of geophysical research. Biogeosciences 20200901 9

Watershed nitrogen (N) budgets provide insights into drivers and solutions for groundwater and surface water N contamination. We constructed a comprehensive N budget for the transboundary Nooksack River Watershed (British Columbia, Canada and Washington, US) using locally-derived data, national statistics and standard parameters. Feed imports for dairy (mainly in the US) and poultry (mainly in Canada) accounted for 30 and 29% of the total N input to the watershed, respectively. Synthetic fertili ...[more]

PMID: 34336541

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Dataset Information

Key components and contrasts in the nitrogen budget across a US-Canadian transboundary watershed.

Publications

Key components and contrasts in the nitrogen budget across a US-Canadian transboundary watershed.

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