Dataset Information

Productivity depends more on the rate than the frequency of N addition in a temperate grassland.

ABSTRACT: 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)) of N application in stimulating ANPP at both the community- and species-levels are largely unknown. By independently manipulating the rate and frequency of N input, with nine rates (from 0 to 50?g N m(-2) year(-1)) crossed with two frequencies (twice year(-1) or monthly) in a temperate steppe of northern China across 2008-2013, we found that N addition increased community ANPP, and had positive, negative, or neutral effects for individual species. There were similar ANPP responses at the community- or species-level when a particular annual amount of N was added either twice year(-1) or monthly. The community ANPP was less sensitive to soil ammonium at lower frequency of N addition. ANPP responses to N addition were positively correlated with annual precipitation. Our results suggest that, over a five-year period, there will be similar ANPP responses to a given annual N input that occurs either frequently in small amounts, as from N deposition, or that occur infrequently in larger amounts, as from application of N fertilizers.

SUBMITTER: Zhang Y

PROVIDER: S-EPMC4517389 | biostudies-literature | 2015 Jul

REPOSITORIES: biostudies-literature

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Productivity depends more on the rate than the frequency of N addition in a temperate grassland.

Zhang Yunhai Y Feng Jinchao J Isbell Forest F Lü Xiaotao X Han Xingguo X

Scientific reports 20150728

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)) of N application in stimulating ANPP at both the community- and species-levels are largely unknown. By independently manipulating the rate and frequency of N input, with nine rates (from 0 to 50 g N m(-2) year(-1)) crossed with two frequencies (twice year(-1) or monthly) in a temperate steppe of northern China a ...[more]

PMID: 26218675

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Productivity depends more on the rate than the frequency of N addition in a temperate grassland.

Publications

Productivity depends more on the rate than the frequency of N addition in a temperate grassland.

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