title: Responses of plant community composition and biomass production to warming and nitrogen deposition in a temperate meadow ecosystem.
abstract: Climate change has profound influences on plant community composition and ecosystem functions. However, its effects on plant community composition and biomass production are not well understood. A four-year field experiment was conducted to examine the effects of warming, nitrogen (N) addition, and their interactions on plant community composition and biomass production in a temperate meadow ecosystem in northeast China. Experimental warming had no significant effect on plant species richness, evenness, and diversity, while N addition highly reduced the species richness and diversity. Warming tended to reduce the importance value of graminoid species but increased the value of forbs, while N addition had the opposite effect. Warming tended to increase the belowground biomass, but had an opposite tendency to decrease the aboveground biomass. The influences of warming on aboveground production were dependent upon precipitation. Experimental warming had little effect on aboveground biomass in the years with higher precipitation, but significantly suppressed aboveground biomass in dry years. Our results suggest that warming had indirect effects on plant production via its effect on the water availability. Nitrogen addition significantly increased above- and below-ground production, suggesting that N is one of the most important limiting factors determining plant productivity in the studied meadow steppe. Significant interactive effects of warming plus N addition on belowground biomass were also detected. Our observations revealed that environmental changes (warming and N deposition) play significant roles in regulating plant community composition and biomass production in temperate meadow steppe ecosystem in northeast China.
authors: Institute of Grassland Sciences, Northeast Normal University, Key Laboratory of Vegetation Ecology, Ministry of Education, Changchun, China; State Key Laboratory of Desert and Oasis Ecology, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi, China.
authors: Tao
authors: T
authors: Zhang
authors: Institute of Environment and Sustainable Development in Agriculture, Chinese Academy of Agricultural Sciences, Key Laboratory of Dryland Agriculture, Ministry of Agriculture, Beijing, China.
authors: Rui
authors: R
authors: Guo
authors: Institute of Grassland Sciences, Northeast Normal University, Key Laboratory of Vegetation Ecology, Ministry of Education, Changchun, China.
authors: Song
authors: S
authors: Gao
authors: Institute of Grassland Sciences, Northeast Normal University, Key Laboratory of Vegetation Ecology, Ministry of Education, Changchun, China.
authors: Jixun
authors: J
authors: Guo
authors: Institute of Grassland Sciences, Northeast Normal University, Key Laboratory of Vegetation Ecology, Ministry of Education, Changchun, China.
authors: Wei
authors: W
authors: Sun
mesh_terms: D000383:Agriculture / Q000379:methods*; D018533:Biomass; D002681:China; D002980:Climate; D057231:Climate Change; D017753:Ecosystem; D057232:Global Warming; D015233:Models, Statistical; D009584:Nitrogen / Q000737:chemistry*; D006109:Poaceae / Q000502:physiology*; D012987:Soil; D013696:Temperature; D014867:Water / Q000737:chemistry
chemical_list: D012987:Soil; D014867:Water; D009584:Nitrogen