AUTHOR=Liang Kang , Jiang Yefang , Fuller Keith , Cordeiro Marcos , Zhang Xuesong , Qi Junyu , Geng Xiaoyuan , Liu Tao , Zhang Qian , Azimi Mohammad Amir , Meng Fan-Rui TITLE=Large variability of nitrate load estimated from sparse measurements by typical methods in Atlantic Canada JOURNAL=Frontiers in Environmental Science VOLUME=13 YEAR=2025 URL=https://www.frontiersin.org/journals/environmental-science/articles/10.3389/fenvs.2025.1557004 DOI=10.3389/fenvs.2025.1557004 ISSN=2296-665X