Premium
Cumulative and partially recoverable impacts of nitrogen addition on a temperate steppe
Author(s) -
Hao Tianxiang,
Song Ling,
Goulding Keith,
Zhang Fusuo,
Liu Xuejun
Publication year - 2018
Publication title -
ecological applications
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.864
H-Index - 213
eISSN - 1939-5582
pISSN - 1051-0761
DOI - 10.1002/eap.1647
Subject(s) - species richness , steppe , biomass (ecology) , grassland , ecosystem , temperate climate , ecology , grassland degradation , environmental science , nitrogen , agronomy , terrestrial ecosystem , biodiversity , nutrient , diversity index , biology , chemistry , organic chemistry
Atmospheric nitrogen (N) deposition has been shown to decrease biodiversity and change nutrient cycles in terrestrial ecosystems. However, our understanding of ecological responses to chronic N addition and ecological recovery of grassland from N enrichment is limited. Here we present evidence from an 11‐year grassland experiment with a range of N addition rates (0, 30, 60, 120, 240, and 480 kg N·ha −1 ·yr −1 ) in Inner Mongolia, China. Chronic N addition led to a reduction in species richness, Shannon diversity index, and soil pH and an increase in aboveground biomass, foliar N, and soil mineral N. High N addition rates (240 and 480 kg N·ha −1 ·yr −1 ) showed significant effects in the first and second years, which stabilized over time. Nitrogen addition at low rates (30 and 60 kg N·ha −1 ·yr −1 ) took longer (e.g., three years or more) to achieve significant effects. The negative impacts of high N addition (480 kg N·ha −1 ·yr −1 ) were reduced and species richness, Shannon diversity index, and soil pH showed a limited but rapid recovery with the cessation of N addition. Our findings suggest serious and cumulative impacts of N addition on plant and soil communities but the potential for partial system recovery over time if N inputs decline or cease.