养分添加对天山高寒草地植物多样性和地上生物量的影响  

Effects of nutrient addition on plant diversity and above-ground biomass in alpine grasslands of Tianshan Mountains, China

作　　者：陈丽 田新民 任正炜[3] 董六文 谢晨笛 周小龙 CHEN Li;TIAN Xin-Min;REN Zheng-Wei;DONG Liu-Wen;XIE Chen-Di;ZHOU Xiao-Long(Xinjiang Key Laboratory of Biological Resources and Genetic Engineering,College of Life Science and Technology,Xinjiang University,Ürümqi 830046,China;Key Laboratory of Oasis Ecology of Ministry of Education,College of Resources and Environmental Sciences,Xinjiang University,Ürümqi 830046,China;State Key Laboratory of Grassland Agro-Ecosystems,Lanzhou University,Lanzhou 730000,China)

机构地区：[1]新疆大学生命科学与技术学院,新疆生物资源基因工程重点实验室,乌鲁木齐830046 [2]新疆大学资源与环境科学学院,绿洲生态教育部重点实验室,乌鲁木齐830046 [3]兰州大学草地农业生态系统国家重点实验室,兰州730000

出　　处：《植物生态学报》2022年第3期280-289,共10页Chinese Journal of Plant Ecology

基　　金：新疆维吾尔自治区创新环境(人才、基地)建设专项(自然科学基金)(2019D01C066);新疆维吾尔自治区天山雪松计划(2020XS26);国家自然科学基金(32060285)。

摘　　要：为揭示高寒草地物种多样性和地上生物量以及二者之间关系对养分添加的响应模式,该研究以天山高寒草地为对象,通过两年的多重养分添加实验,研究氮(N)、磷(P)、钾(K)3种养分单独和组合添加对天山高寒草地群落物种多样性和地上生物量的影响。结果表明:(1)养分添加使当地植物物种多样性不同程度地减少,其中以N+P、N+K、N+P+K添加的效应最为显著,多重养分添加导致的土壤生态位维度降低是当地物种丧失的重要原因。(2)养分添加能显著提高群落地上生物量,其中N为第一限制养分,解除N限制后P和K成为限制养分, N+P+K复合添加对地上生物量的提高最为显著。(3)养分添加两年后,地上生物量与物种丰富度之间无显著回归关系且地上生物量增加主要是由于禾草类生物量增加导致,说明地上生物量主要由少数优势种决定而非群落物种数。Aims The objectives were to reveal the response patterns of plant species diversity and above-ground biomass to nutrients addition and to clarify their relationships in alpine grasslands of Tianshan Mountains.Methods The nitrogen(N), phosphorus(P) and potassium(K) addition experiments were conducted in Tianshan alpine grasslands. The single factor effects and the interaction effects on plant species diversity and above-ground biomass were studied from 2019 to 2020.Important findings 1) Nutrient addition reduced plant species diversity of local community. Especially, the addition of N + P, N + K and N + P + K showed significant effects, suggesting that the decrease of soil niche dimension caused by multiple-nutrient addition was an important reason for local species loss. 2) Nutrient addition significantly increased above-ground biomass of local plant communities, with the highest above-ground biomass being found under N + P + K treatment, indicating that N was the first limiting resource, P and K became the limiting resources after N limiting was alleviated. 3) There was a negative linear regression between species diversity and above-ground biomass following two years of nutrient addition, which indicated that the dominant species but not species diversity determined above-ground biomass at our study site.

关 键 词：氮 磷 钾 物种多样性 地上生物量 天山高寒草地 巴音布鲁克 

分 类 号：S812[农业科学—草业科学]