西南农业学报2025，Vol.38Issue(7)：1367-1376,10.DOI:10.16213/j.cnki.scjas.2025.7.002
氮素添加对高寒草甸植物和土壤碳氮库权衡的影响
Effects of nitrogen addition on alpine meadow plant and soils,carbon and nitrogen pool trade-off
摘要
Abstract
[Objective]The present paper aimed to investigate the multifactor-driven regulation of the trade-off relationship between plant and soil carbon and nitrogen pools in alpine meadows under nitrogen addition,the study investigated the effects of nitrogen addition on the carbon and nitrogen pools of alpine meadow plants in the aboveground community,carbon and nitrogen pools in the root system,and total carbon and nitrogen pools of the plant and the soil carbon and nitrogen pools.[Method]The alpine meadows of the Qinghai-Tibetan Plateau were used as the research object,and five treatment groups were set up:CK(0 g/m2),T1(15 g/m2),T2(30 g/m2),T3(45 g/m2)and T4(60 g/m2),and the dynamic changes and plant-soil trade-offs between plant and soil were analyzed by analyzing the plant C and nitrogen pools,the soil organic C pools and nitrogen pools of alpine meadow plants under the nitrogen additions at different levels.Dynamic changes and the driving factors of plant-soil trade-off relationships.[Result]The positive effect of nitrogen addition on plant carbon and nitrogen pools was sig-nificant,and the aboveground community carbon and nitrogen pools,root carbon and nitrogen pools,and total plant community carbon and ni-trogen pools of alpine meadow plants all had their maximum values in the T2 treatment.With the addition of nitrogen,the carbon pools of the soil had a peak at T2 treatment.The trade-off analysis showed that the trade-off relationship between total plant community carbon pools and soil carbon pools under each nitrogen addition treatment was in the order of T1(0.0351)＞T3(0.0243)＞CK(0.0236)＞T2(0.0152)＞T4(0.0034),and the trade-off relationship between total plant community nitrogen pools and soil nitrogen pools was in the order of T1(0.0399)＞T3(0.031)＞CK(0.0298)＞T4(0.017)＞T2(0.0148).Propensity analysis showed that the carbon and nitrogen pools of plant and soil under nitrogen addition favored plant at T3 treatment and soil at T2 treatment.Structural equation modeling showed that the trade-off between total plant community carbon(nitrogen)pools and soil carbon(nitrogen)pools and TN were significantly positively corre-lated.[Conclusion]The aboveground community carbon and nitrogen pools,root carbon and nitrogen pools,total plant community carbon and nitrogen pools and soil nitrogen pools all had maximum values at T2 treatment,and the carbon and nitrogen pools of plants and soil tended to favor the soil at T2 treatment.The study can provide scientific guidance for the turnover and circulation of carbon and nitrogen pools in alpine meadows,and facilitate researchers engaged in the study of carbon and nitrogen cycling to crystallize scientific problems.关键词
三江源区/高寒草甸/碳库/氮库/权衡Key words
Sanjiangyuan area/Alpine meadow/Carbon pools/Nitrogen pools/Trade-off分类
农业科技引用本文复制引用
林伟山,张琳,德科加,向雪梅,冯廷旭,李菲,魏希杰..氮素添加对高寒草甸植物和土壤碳氮库权衡的影响[J].西南农业学报,2025,38(7):1367-1376,10.基金项目
青海省科技厅重点研发与转化计划项目(2024-NK-137) （2024-NK-137）
称多县一年生饲草种子繁殖与青贮加工贮藏技术研究与示范项目(2024-NK-P28) （2024-NK-P28）
三江源生态系统教育部野外科学观测研究站(K9922050) （K9922050）
