Multiple mechanisms contributed to the reduced stability of Inner Mongolia grassland ecosystem following nitrogen enrichment

作者：Chen, Wenqing^*; Zhang, Yingjun; Mai, Xiaohu; Shen, Yue

来源：Plant and Soil, 2016, 409(1-2): 283-296.

DOI：10.1007/s11104-016-2967-1

• Community stability
• Dominant species
• Ecosystemfunction
• Inner Mongolia grassland
• Nitrogen addition
• Plant diversity

Global nitrogen enrichment has been identified as a major environmental problem that poses a threat to ecosystem functioning. However, there is no consensus on the impact of enriched nitrogen on ecosystem stability or the underlying mechanisms driving that impact. @@@ We conducted a 5-year multi-level nitrogen addition experiment in Inner Mongolia grassland. We determined plant diversity, species asynchrony, population stability, functional group stability and dominant stability, focusing on investigating the impact of nitrogen enrichment on stability and the driving mechanisms. @@@ Community stability responded negatively to nitrogen enrichment. Added nitrogen decreased plant diversity, and had a direct negative effect on species asynchrony, graminoid functional group stability, population stability, and dominant stability; all of these showed tight associations with reduced community stability. In addition, community stability showed no significant response at nitrogen addition rate <= 1.01 g N m(-2) year(-1), and saturated at >= 9.17 g N m(-2) year(-1). @@@ Nitrogen-induced reduction in diversity, together with alterations in species asynchrony, graminoid functional group stability, population stability and dominant stability, worked concurrently leading to deceased stability in the Inner Mongolia grassland. In addition, an effect threshold and saturation rate for added nitrogen was observed.

• 出版日期2016-12
• 单位甘肃农业大学; 中国农业大学; 西北农林科技大学