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Abstract Increasing food and biofuel demands have led to the cascading effects from cropland expansions, raised fertilizer use, to increased riverine nitrogen (N) loads. However, little is known about the current trade-off between riverine N pollution and crop production due to the lack of predictive understanding of ecological processes across the land-aquatic continuum. Here, we propose a riverine N footprint (RNF) concept to quantify how N loads change along with per unit crop production gain. Using data synthesis and a well-calibrated hydro-ecological model, we find that the RNF within the Mississippi–Atchafalaya River Basin peaked at 1.95 g N kg−1grain during the 1990s, and then shifted from an increasing to a decreasing trend, reaching 0.65 g N kg−1grain in the 2010s. This implies decoupled responses of crop production and N loads to key agricultural activities approximately after 2000, but this pattern varies considerably among sub-basins. Our study highlights the importance of developing a food–energy–water nexus indicator to examine the region-specific trade-offs between crop production and land-to-aquatic N loads for achieving nutrient mitigation goals while sustaining economic gains.
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Anthropogenic nitrogen Balance and Riverine Nitrogen Footprint of Agriculture in the Mississippi-Atchafalaya River Basin during 1970-2019
These data support the findings of a manuscript by Lu et al. under review in Environmental Research Letters. We used data synthesis and a well-calibrated hydro-ecological model to quantify the dynamics and controls of the riverine N footprint (RNF) within the Mississippi-Atchafalaya River Basin (MARB) from 1970 to 2019. These supportive data include (1) Annual synthetic N fertilizer and manure N input from 1970 to 2019 in sub-basins in the MARB; (2) Annual N inputs, outputs, and N balance from 1970 to 2017 in the MARB; (3) Changes in crop production, N load and riverine N footprint in response to key agricultural activities in MARB; (4) Changes in crop production, N load, and riverine N footprint under key agricultural activities at sub-basin level; (5) Annual acreage of major grain crops and total cropland areas in sub-basins of the MARB.
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- Award ID(s):
- 1945036
- PAR ID:
- 10590592
- Publisher / Repository:
- Environmental Data Initiative
- Date Published:
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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