title: Warming and Nitrogen Addition Alter Photosynthetic Pigments, Sugars and Nutrients in a Temperate Meadow Ecosystem.
abstract: Global warming and nitrogen (N) deposition have an important influence on terrestrial ecosystems; however, the influence of warming and N deposition on plant photosynthetic products and nutrient cycling in plants is not well understood. We examined the effects of 3 years of warming and N addition on the plant photosynthetic products, foliar chemistry and stoichiometric ratios of two dominant species, i.e., Leymus chinensis and Phragmites communis, in a temperate meadow in northeastern China. Warming significantly increased the chlorophyll content and soluble sugars in L. chinensis but had no impact on the carotenoid and fructose contents. N addition caused a significant increase in the carotenoid and fructose contents. Warming and N addition had little impact on the photosynthetic products of P. communis. Warming caused significant decreases in the N and phosphorus (P) concentrations and significantly increased the carbon (C):P and N:P ratios of L. chinensis, but not the C concentration or the C:N ratio. N addition significantly increased the N concentration, C:P and N:P ratios, but significantly reduced the C:N ratio of L. chinensis. Warming significantly increased P. communis C and P concentrations, and the C:N and C:P ratios, whereas N addition increased the C, N and P concentrations but had no impact on the stoichiometric variables. This study suggests that both warming and N addition have direct impacts on plant photosynthates and elemental stoichiometry, which may play a vital role in plant-mediated biogeochemical cycling in temperate meadow ecosystems.
authors.affiliation: Institute of Grassland Science, Northeast Normal University, Key Laboratory of Vegetation Ecology, Ministry of Education, Changchun, China.
authors.forename: Tao
authors.initials: T
authors.lastname: Zhang
authors.affiliation: Institute of Grassland Science, Northeast Normal University, Key Laboratory of Vegetation Ecology, Ministry of Education, Changchun, China.
authors.forename: Shaobo
authors.initials: S
authors.lastname: Yang
authors.affiliation: Institute of Environment and Sustainable Development in Agriculture, Chinese Academy of Agricultural Sciences, Key Laboratory of Dryland Agriculture, Ministry of Agriculture, Beijing, China.
authors.forename: Rui
authors.initials: R
authors.lastname: Guo
authors.affiliation: Institute of Grassland Science, Northeast Normal University, Key Laboratory of Vegetation Ecology, Ministry of Education, Changchun, China.
authors.forename: Jixun
authors.initials: J
authors.lastname: Guo
mesh_terms: D000704:Analysis of Variance; D002241:Carbohydrates / Q000032:analysis*; D002244:Carbon / Q000032:analysis; D017753:Ecosystem; D057232:Global Warming; D006813:Humidity; D008834:Microclimate; D009584:Nitrogen / Q000032:analysis*; D010758:Phosphorus / Q000032:analysis*; D010788:Photosynthesis; D010860:Pigments, Biological / Q000032:analysis*; D018515:Plant Leaves / Q000737:chemistry; D012987:Soil / Q000737:chemistry; D012995:Solubility; D013696:Temperature
chemical_list: D002241:Carbohydrates; D010860:Pigments, Biological; D012987:Soil; D010758:Phosphorus; D002244:Carbon; D009584:Nitrogen