Modeling denitrification nitrogen losses in China's rice fields based on multiscale field‐experiment constraints

作者：Huayan Zhang, Wulahati Adalibieke, Wenxin Ba, Klaus Butterbach‐Bahl, Longfei Yu, Andong Cai, Fu Jin, Haoming Yu, Wantong Zhang, Weichen Huang, Yiwei Jian, Wenjun Jiang, Zheng Zhao, Jiafa Luo, Jia Deng, Feng Zhou · 发表于：Global Change Biology · 年份：2024 · DOI：10.1111/gcb.17199 · 被引用次数：13 · 研究领域：Rice Cultivation and Yield Improvement、Soil and Water Nutrient Dynamics、Wastewater Treatment and Nitrogen Removal

Abstract Denitrification plays a critical role in soil nitrogen (N) cycling, affecting N availability in agroecosystems. However, the challenges in direct measurement of denitrification products (NO, N 2 O, and N 2 ) hinder our understanding of denitrification N losses patterns across the spatial scale. To address this gap, we constructed a data‐model fusion method to map the county‐scale denitrification N losses from China's rice fields over the past decade. The estimated denitrification N losses as a percentage of N application from 2009 to 2018 were 11.8 ± 4.0% for single rice, 12.4 ± 3.7% for early rice, and 11.6 ± 3.1% for late rice. The model results showed that the spatial heterogeneity of denitrification N losses is primarily driven by edaphic and climatic factors rather than by management practices. In particular, diffusion and production rates emerged as key contributors to the variation of denitrification N losses. These findings humanize a 38.9 ± 4.8 kg N ha −1 N loss by denitrification and challenge the common hypothesis that substrate availability drives the pattern of N losses by denitrification in rice fields.