title: Nitrogen acquisition by plants and microorganisms in a temperate grassland.
abstract: Nitrogen (N) limitation is common in most terrestrial ecosystems, often leading to strong competition between microorganisms and plants. The mechanisms of niche differentiation to reduce this competition remain unclear. Short-term (15)N experiments with NH4(+), NO3(-), and glycine were conducted in July, August and September in a temperate grassland to evaluate the chemical, spatial and temporal niche differentiation by competition between plants and microorganisms for N. Microorganisms preferred NH4(+) and NO3(-), while plants preferred NO3(-). Both plants and microorganisms acquired more N in August and September than in July. The soil depth had no significant effects on microbial uptake, but significantly affected plant N uptake. Plants acquired 67% of their N from the 0-5 cm soil layer and 33% from the 5-15 cm layer. The amount of N taken up by microorganisms was at least seven times than plants. Although microorganisms efficiently compete for N with plants, the competition is alleviated through chemical partitioning mainly in deeper soil layer. In the upper soil layer, neither chemical nor temporal niche separation is realized leading to strong competition between plants and microorganisms that modifies N dynamics in grasslands.
authors.affiliation: Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources, Chinese Academy of Sciences, Beijing 100101, China.|University of Chinese Academy of Sciences, Beijing 100049, China.
authors.forename: Qianyuan
authors.initials: Q
authors.lastname: Liu
authors.affiliation: University of Chinese Academy of Sciences, Beijing 100049, China.|Key Laboratory of Tropical Forest Ecology, Chinese Academy of Sciences, Xishuangbanna Tropical Botanical Garden, Menglun, Mengla, Yunnan 666303, China.
authors.forename: Na
authors.initials: N
authors.lastname: Qiao
authors.affiliation: Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources, Chinese Academy of Sciences, Beijing 100101, China.|Hulunber Grassland Ecosystem Observation and Research Station, Institute of Agricultural Resources and Regional Planning of Chinese Academy of Agricultural Sciences, Beijing, China 100081.
authors.forename: Xingliang
authors.initials: X
authors.lastname: Xu
authors.affiliation: Hulunber Grassland Ecosystem Observation and Research Station, Institute of Agricultural Resources and Regional Planning of Chinese Academy of Agricultural Sciences, Beijing, China 100081.
authors.forename: Xiaoping
authors.initials: X
authors.lastname: Xin
authors.affiliation: University of Chinese Academy of Sciences, Beijing 100049, China.|The Center for Integrative Conservation, Xishuangbanna Tropical Botanical Garden, Menglun, Chinese Academy of Sciences, Mengla, Yunnan 666303, China.
authors.forename: Jessie Yc
authors.initials: JY
authors.lastname: Han
authors.affiliation: State Key Laboratory of Earth Surface Processes and Resource Ecology, Beijing Normal University, No. 19, XinJieKouWai Street, Haidian District, Beijing 100875, China.
authors.forename: Yuqiang
authors.initials: Y
authors.lastname: Tian
authors.affiliation: Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources, Chinese Academy of Sciences, Beijing 100101, China.
authors.forename: Hua
authors.initials: H
authors.lastname: Ouyang
authors.affiliation: Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources, Chinese Academy of Sciences, Beijing 100101, China.|Department of Soil Science of Temperate Ecosystems and Department of Agricultural Soil Science, University of Göttingen, Göttingen, Germany.|Institute of Environmental Sciences, Kazan Federal University, Kazan, Russia.
authors.forename: Yakov
authors.initials: Y
authors.lastname: Kuzyakov
mesh_terms: D001419:Bacteria / Q000378:metabolism*; D005658:Fungi / Q000378:metabolism*; D005998:Glycine / Q000378:metabolism; D065948:Grassland; D009584:Nitrogen / Q000378:metabolism*; D009586:Nitrogen Fixation; D010944:Plants / Q000378:metabolism*; D012621:Seasons
chemical_list: D009584:Nitrogen; D005998:Glycine