title: Nitrogen addition affects chemical compositions of plant tissues, litter and soil organic matter.
abstract: Increasing nitrogen (N) deposition or fertilization has been found to significantly affect carbon (C) cycling. However, a comprehensive understanding of how different C chemical components of plant, litter, and soil would respond to external N addition is still lacking. We compiled data of 1,160 observations from 52 individual studies and conducted a meta-analysis of N addition effects on 18 variables related to C chemical compositions in terrestrial ecosystems. Results showed that plant lignin (+7.13%), plant protein (+25.94%), and soil lignin (+7.30%) were significantly increased by N addition, and plant hemicellulose (-4.39%) was significantly decreased, whereas plant fiber, plant cellulose, plant non-structural carbohydrate (NSC), litter lignin, and litter cellulose were not significantly changed. The effects of N addition on C chemical composition varied among different ecosystems/plant types and different forms of N addition. Increasing treatment duration did not significantly change the effects of N addition on the chemical composition of plant, litter, and soil C. With increasing N addition rate, the effect of N addition on plant lignin, plant fiber, plant cellulose, and plant protein increased, while the effect of N addition on plant hemicellulose, plant NSC, and litter cellulose became more negative. Our meta-analysis provided a systematic evaluation of the responses of different C chemical components to N addition in the plant-litter-soil continuum. Results suggest that the change of plant and soil C chemical composition under N addition may be beneficial for ecosystem C sequestration and could affect ecosystem structure and function in the future.
authors.affiliation: Key Laboratory of Forest Ecology and Management, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang, 110016, China.|University of Chinese Academy of Sciences, Beijing, 100049, China.
authors.forename: Jun
authors.initials: J
authors.lastname: Liu
authors.affiliation: Key Laboratory of Forest Ecology and Management, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang, 110016, China.
authors.forename: Nana
authors.initials: N
authors.lastname: Wu
authors.affiliation: Key Laboratory of Forest Ecology and Management, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang, 110016, China.
authors.forename: Hui
authors.initials: H
authors.lastname: Wang
authors.affiliation: Key Laboratory of Forest Ecology and Management, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang, 110016, China.
authors.forename: Jianfei
authors.initials: J
authors.lastname: Sun
authors.affiliation: Key Laboratory of Forest Ecology and Management, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang, 110016, China.
authors.forename: Bo
authors.initials: B
authors.lastname: Peng
authors.affiliation: Key Laboratory of Forest Ecology and Management, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang, 110016, China.
authors.forename: Ping
authors.initials: P
authors.lastname: Jiang
authors.affiliation: Key Laboratory of Forest Ecology and Management, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang, 110016, China.
authors.forename: Edith
authors.initials: E
authors.lastname: Bai
mesh_terms: D002244:Carbon; D017753:Ecosystem; D004784:Environmental Monitoring; D009584:Nitrogen / Q000032:analysis*; D018515:Plant Leaves; D010944:Plants / Q000737:chemistry*; D012987:Soil / Q000737:chemistry*
chemical_list: D012987:Soil; D002244:Carbon; D009584:Nitrogen
keywords: carbon cycle; cellulose; lignin; meta-analysis; nitrogen deposition; non-structural carbohydrate