中国草地学报2026，Vol.48Issue(5)：81-94,14.DOI:10.16742/j.zgcdxb.20250407
氮磷添加对藏东南高寒草甸植物群落及土壤理化性质的影响
Effects of Nitrogen and Phosphorus Addition on Plant Communities and Soil Physicochemical Properties in an Alpine Meadow of Southeastern Xizang
摘要
Abstract
In recent years,the intensification of global nitrogen deposition has induced a shift from traditional N limitation to phosphorus limitation in alpine meadows.However,whether phosphorus supplementation alleviates or exacerbates the negative effects of nitrogen deposition remains to be systematically elucidated.To clarify the regula-tory mechanisms of combined nitrogen and phosphorus addition on plant community and soil properties in alpine meadows,a five-year field control experiment was conducted in the alpine meadow of the Sejila Mountains in south-eastern Xizang starting in 2019.A total of nine combined nitrogen and phosphorus addition treatments with varying gradients[nitrogen:50,75 and 100 kg/(hm²·a);phosphorus:10,15 and 20 kg/(hm²·a)]were established,along with a control treatment(Natural condition).The results indicated that:Long-term combined nitrogen and phospho-rus addition significantly led to plant diversity decline and community structure differentiation(P<0.05),with the Shannon-Wiener index showing a maximum reduction of 21.32%under the high nitrogen and phosphorus treatment;The regulatory effect of phosphorus input on plant community characteristics exhibited a distinct nitrogen-level dependency.Under the low nitrogen treatment[50 kg/(hm²·a)],phosphorus addition effectively alleviated diversity loss with increasing phosphorus application;however,this mitigating effect was no longer significant under the high nitrogen background[100 kg/(hm²·a)];Nutrient inputs altered interspecific competition patterns,with the dominance of Cyperaceae species increasing with nutrient addition,while that of Asteraceae species significantly decreased(P<0.05);Long-term nitrogen and phosphorus addition significantly reduced soil pH(P<0.05),with greatest reduction of 8.28%observed under high nitrogen and high phosphorus treat-ment.Simultaneously,soil available potassium content decreased significantly across all fertilization treatments(P<0.05),with a maximum reduction of 52.79%observed under the high nitrogen and low phosphorus treat-ment.Correlation analysis further revealed a significant positive correlation between soil pH,available potas-sium content,and plant diversity(P<0.05).In conclusion,high-intensity joint nutrient inputs represent a criti-cal driving force for plant diversity decline and soil acidification in alpine meadows,while phosphorus availabil-ity plays a buffering role under low nitrogen conditions,albeit with limited regulatory capacity under high nitro-gen backgrounds.Long-term nitrogen and phosphorus inputs further affect plant community stability by acidify-ing the soil and altering nutrient balance.关键词
氮磷添加/高寒草甸/植物群落演替/土壤养分平衡/青藏高原Key words
Nitrogen and phosphorus addition/Alpine meadow/Plant community succession/Soil nutrient balance/Qinghai-Xizang Plateau分类
农业科技引用本文复制引用
黄文强,吴正,仝令臣,韩艳英,刘爽,周玉柳,叶彦辉..氮磷添加对藏东南高寒草甸植物群落及土壤理化性质的影响[J].中国草地学报,2026,48(5):81-94,14.基金项目
西藏自治区科技计划重点研发计划项目(XZ202401ZY0032) （XZ202401ZY0032）
西藏自治区科技计划重大专项(XZ202101ZD003N) （XZ202101ZD003N）
林芝市科技计划项目(2023-XYQ-006) （2023-XYQ-006）
西藏农牧学院研究生教育创新计划项目(YJS2022-07,YJS2023-11) （YJS2022-07,YJS2023-11）
西藏农牧学院林学博士点(一期)项目(533325001) （一期）
西藏农牧学院第七批柔性人才项目(53013001804) （53013001804）
