Agriculture's impact on water-energy balance varies across climates

• 成果类型: Article
• 署名作者: Zaerpour, Masoud; Hatami, Shadi; Papalexiou, Simon Michael; Pietroniro, Alain; Nazemi, Ali
• 署名单位: University of Calgary; Universidade de Sao Paulo; Czech University of Life Sciences Prague; Concordia University - Canada
• 刊物名称: PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
• ISSN/ISSBN: 0027-9223
• DOI: 10.1073/pnas.2410521122
• 发表日期: 2025-03-25
• 关键词: us high-plains; surface-water; groundwater depletion; time-series; base-flow; streamflow; precipitation; irrigation; catchment; evapotranspiration

摘要

Agriculture is a cornerstone of global food production, accounting for a substantial portion of water withdrawals worldwide. As the world's population grows, so does the demand for water in agriculture, leading to alterations in regional water-energy balances. We present an approach to identify the influence of agriculture on the water-energy balance using empirical data. We explore the departure from the Budyko curve for catchments with agricultural expansion and their associations with changes in the water-energy balance using a causal discovery algorithm. Analyzing data from 1,342 catchments across three K & ouml;ppen-Geiger climate classes-temperate, snowy, and others-from 1980 to 2014, we show that temperate and snowy catchments, which account for over 90% of stations, exhibit distinct patterns. Cropland percentage (CL%) emerges as the dominant factor, explaining 47 and 37% of the variance in deviations from the Budyko curve in temperate and snowy catchments, respectively. In temperate catchments, CL% shows a strong negative correlation with precipitation-streamflow (P-Q) causal strength (Spearman p = -0.75), suggesting that cropland exacerbates precipitation-driven deviations. A moderate negative correlation with aridity-streamflow (AR-Q) causal strength ( p = -0.42) indicates additional influences of cropland through aridity-driven interactions. In snowy catchments, CL% is similarly influential, with a positive correlation with P-Q causal strength ( p = 0.51). However, the negative correlation with AR-Q causal strength ( p = -0.45) underscores the role of aridity as a secondary driver. While vegetation and precipitation seasonality also contribute to the deviations, their impacts are comparatively lower. These findings underscore the need for inclusion of agricultural activities in changing water-energy balance to secure future water supplies.