作者: Yunhai Zhang , Jinchao Feng , Forest Isbell , Xiaotao Lü , Xingguo Han
DOI: 10.1038/SREP12558
关键词: Precipitation 、 Animal science 、 Productivity (ecology) 、 Biology 、 Deposition (chemistry) 、 Terrestrial ecosystem 、 Primary production 、 Ecology 、 Steppe 、 Temperate climate 、 Ammonium
摘要: Nitrogen (N) is a key limiting resource for aboveground net primary productivity (ANPP) in diverse terrestrial ecosystems. The relative roles of the rate and frequency (additions yr(-1)) N application stimulating ANPP at both community- species-levels are largely unknown. By independently manipulating input, with nine rates (from 0 to 50 g m(-2) year(-1)) crossed two frequencies (twice year(-1) or monthly) temperate steppe northern China across 2008-2013, we found that addition increased community ANPP, had positive, negative, neutral effects individual species. There were similar responses species-level when particular annual amount was added either twice monthly. less sensitive soil ammonium lower addition. positively correlated precipitation. Our results suggest that, over five-year period, there will be given input occurs frequently small amounts, as from deposition, occur infrequently larger fertilizers.