Increasing phosphorus loss despite widespread concentration decline in US rivers

• 成果类型: Article
• 署名作者: Zhi, Wei; Baniecki, Hubert; Liu, Jiangtao; Boyer, Elizabeth; Shen, Chaopeng; Shenk, Gary; Liu, Xiaofeng; Li, Li
• 署名单位: Hohai University; Pennsylvania Commonwealth System of Higher Education (PCSHE); Pennsylvania State University; Pennsylvania State University - University Park; University of Warsaw; Warsaw University of Technology; Pennsylvania Commonwealth System of Higher Education (PCSHE); Pennsylvania State University; Pennsylvania State University - University Park; Pennsylvania Commonwealth System of Higher Education (PCSHE); Pennsylvania State University; Pennsylvania State University - University Park; United States Department of the Interior; United States Geological Survey
• 刊物名称: PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
• ISSN/ISSBN: 0027-12296
• DOI: 10.1073/pnas.2402028121
• 发表日期: 2024-11-19
• 关键词: water-quality; anthropogenic phosphorus; dissolved-oxygen; fresh-water; nitrogen; eutrophication; limitation; nutrient; FLOW

摘要

The loss of phosphorous (P) from the land to aquatic systems has polluted waters and threatened food production worldwide. Systematic trend analysis of P, a nonrenewable resource, has been challenging, primarily due to sparse and inconsistent historical data. Here, we leveraged intensive hydrometeorological data and the recent renaissance of deep learning approaches to fill data gaps and reconstruct temporal trends. We trained a multitask long short- term memory model for total P (TP) using data from 430 rivers across the contiguous United States (CONUS). Trend analysis of reconstructed daily records and insignificantly changing trends in 60%, 28%, and 12% of the rivers, respectively. Concentrations in urban rivers have declined the most despite rising urban population in the past decades; concentrations in agricultural rivers however have mostly increased, suggesting not- as- effective controls of nonpoint sources in agriculture lands compared to point sources in cities. TP loss, calculated as fluxes by multiplying concentration and discharge, however exhibited an overall increasing rate of 6.5% per decade at the CONUS scale over the past 40 y, largely due to increasing river discharge. Results highin a warming climate.