Open AccessEffects of climate and soil properties on regional differences in nitrogen use efficiency and reactive nitrogen losses in rice
Author(s) -
Siyuan Cai,
Xu Zhao,
Xiaoyuan Yan
Publication year - 2022
Publication title -
environmental research letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.37
H-Index - 124
ISSN - 1748-9326
DOI - 10.1088/1748-9326/ac6a6b
Subject(s) - nitrogen , leaching (pedology) , environmental science , fertilizer , agronomy , water use efficiency , agricultural soil science , productivity , volatilisation , soil science , soil fertility , chemistry , soil water , irrigation , economics , biology , organic chemistry , macroeconomics , no till farming
Nitrogen (N) use efficiency worldwide varies greatly due to climate, agronomic, and soil factors. However, the information on individual effects of these factors on N use efficiency is crucial but has remained scanty. Given that climate cannot be regulated, understanding the relative importance of fertilizer and soil variations on regional differences in N use efficiency is critical. Here, we constructed a database of 302 studies from 1986 to 2020 in East and Northeast China to determine the effects of climate, soil properties, and fertilizer N rate (FN) on variations in N use efficiency [agronomic efficiency (AE), apparent recovery efficiency (RE), physiological efficiency (PE), N harvest index (NHI), partial factor productivity (PFP)], N surplus, grain N content, and reactive N (Nr) losses (N2O emissions, NH3 volatilization, Nr leaching, and runoff). Rice yield was comparable between two regions under farmers' N practices, yet the N input was considerably higher in East China. All indices of N use efficiency, except RE, are higher in Northeast China. Differences in AE were dominated by the ability of the plant to mobilize N (PE) rather than N uptake (RE), FN, or Nr loss. Soil properties and FN related to optimizable N management accounted for 29% (RE), 39% (PE), and 43% (Nr losses) of the variations, of which key factors as pH showed a negative effect while available N correlated positively to the N use efficiency. To realize high N use efficiency, pivotal effects of pH, available N, and FN on N use efficiency under certain climate zone should be considered.