title: Responses of soil nitrogen fixation to Spartina alterniflora invasion and nitrogen addition in a Chinese salt marsh.
abstract: Biological nitrogen fixation (BNF) is the major natural process of nitrogen (N) input to ecosystems. To understand how plant invasion and N enrichment affect BNF, we compared soil N-fixation rates and N-fixing microbes (NFM) of an invasive Spartina alterniflora community and a native Phragmites australis community in the Yangtze River estuary, with and without N addition. Our results indicated that plant invasion relative to N enrichment had a greater influence on BNF. At each N level, the S. alterniflora community had a higher soil N-fixation rate but a lower diversity of the nifH gene in comparison with the native community. The S. alterniflora community with N addition had the highest soil N-fixation rate and the nifH gene abundance across all treatments. Our results suggest that S. alterniflora invasion can increase soil N fixation in the high N-loading estuarine ecosystem, and thus may further mediate soil N availability.
authors: Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering, Fudan University, 2005 Songhu Rd, Shanghai 200438, Peoples R China.
authors: Jingxin
authors: J
authors: Huang
authors: Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering, Fudan University, 2005 Songhu Rd, Shanghai 200438, Peoples R China.
authors: Xiao
authors: X
authors: Xu
authors: Shanghai Academy of Environmental Sciences, 508 Qinzhou Rd, Shanghai 200233, Peoples R China.
authors: Min
authors: M
authors: Wang
authors: Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering, Fudan University, 2005 Songhu Rd, Shanghai 200438, Peoples R China.
authors: Ming
authors: M
authors: Nie
authors: Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering, Fudan University, 2005 Songhu Rd, Shanghai 200438, Peoples R China.
authors: Shiyun
authors: S
authors: Qiu
authors: Shanghai Academy of Environmental Sciences, 508 Qinzhou Rd, Shanghai 200233, Peoples R China.
authors: Qing
authors: Q
authors: Wang
authors: Department of Microbiology and Microbial Engineering, School of Life Sciences, Fudan University, 2005 Songhu Rd, Shanghai 200438, Peoples R China.
authors: Zhexue
authors: Z
authors: Quan
authors: Department of Biology, Shanghai Normal University, 100 Guilin Rd, Shanghai 200234, Peoples R China.
authors: Ming
authors: M
authors: Xiao
authors: Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering, Fudan University, 2005 Songhu Rd, Shanghai 200438, Peoples R China.
authors: Bo
authors: B
authors: Li
mesh_terms: D000704:Analysis of Variance; D018533:Biomass; D002681:China; D016000:Cluster Analysis; D005798:Genes, Bacterial; D005843:Geography; D058865:Introduced Species; D009586:Nitrogen Fixation; D010802:Phylogeny; D006109:Poaceae / Q000502:physiology*; D012965:Sodium Chloride / Q000737:chemistry*; D012987:Soil; D053833:Wetlands
chemical_list: D012987:Soil; D012965:Sodium Chloride