模拟增温和加雪对高寒草甸植物群落和土壤养分的影响  

Effects of Simulated Warming and Snow Addition on Plant Community and Soil Nutrient in Alpine Meadow

作　　者：陈若欣 尹正辉 斯确多吉[3] 拉多[1,2] CHEN Ruoxin;YIN Zhenghui;Tsechoe-Dorji;Lhaduo(School of Ecology and Environment,Tibet University,Lhasa 850000,China;Maidika Wetland Field Observation Station,College of Ecology and Environment,Tibet University,Nagqu 852000,China;State Key Laboratory of Tibetan Plateau Earth System Resources Environment,Institute of Tibetan Plateau Research,Beining 100101,China)

机构地区：[1]西藏大学生态环境学院,西藏拉萨850000 [2]西藏大学生态环境学院麦地卡湿地野外观测站,西藏那曲852000 [3]中国科学院青藏高原研究所高塞生态重点实验室,北京100101

出　　处：《高原科学研究》2024年第4期22-30,共9页Plateau Science Research

基　　金：国家自然科学基金联合基金项目(U20A2005)。

摘　　要：以西藏纳木错湖区高寒草甸为研究对象,通过增温和早春雪灾模拟对高寒草甸植物群落结构特征、土壤养分的影响进行了研究。结果表明,区域植物群落均匀度在增温、增温+加雪处理下显著高于对照组,而在加雪处理下其低于对照组,Simpson优势度指数,Shannon-Wiener多样性指数,Margalef丰富度指数在各处理组之间无显著差异。群落优势物种高山嵩草(Carex parvula)重要值在增温和增温+加雪处理下显著低于对照组;增温处理下的植被盖度显著低于对照组、增温+加雪和加雪处理;三种处理下的植被高度均高于对照组,其中增温+加雪处理下其显著高于对照组。不同处理对土壤养分的影响未达到显著群落水平。相关性分析表明,增温处理下,植被盖度与土壤有机碳、含水率、水解性氮呈显著正相关,植被平均高度、Shannon-Weiner指数与pH值呈显著正相关。增温+加雪处理下,植物群落平均高度和Margalef指数与土壤含水率呈显著负相关,而植物群落平均高度与pH值呈显著正相关,Margalef指数与有效磷呈显著正相关。加雪处理下,Pielou指数与有效磷呈显著正相关。对照组的Margalef指数与土壤有机碳、水解性氮呈显著负相关。研究结果揭示了纳木错高寒草甸植被群落和土壤养分对气候变化的响应状况,为西藏高寒草地生态系统应对气候变化的研究提供了科学依据。Taking the alpine meadow plant community at the surrounding Namtso Lake in central Tibet Autono-mous Region as the study object,the effect of climate change on alpine meadow plant community structure,diver-sity and soil nutrients were analysed with Open-Top Chambers(OTCs)treatment simulating warming(Wa)and snow addition(S)treatment as a simulation of early spring snow disaster.The plant community evenness under Wa and warmig+snow addition(SWa)treatments was significantly higher than that in control(C)but it was lower under S treatment.There were no significant differences in Simpson,Shannon-Wiener and Margalef index be-tween treatments.The importance value of dominant species(Carex parvula)was significantly lower under the Wa and SWa treatments than control group.Vegetation coverage was significantly lower under Wa treatment than that in C,S and SWa groups.The vegetation+snow addition height under all three treatments mentioned above was higher than that in control group,among which it was significantly higher under the SWa treatment than that in control group.The effect of different treatments on soil nutrients did not reach to significant level.Correlation analysis showed that vegetation coverage was positively correlated with organic carbon(OC),soil mois-ture content(SMC)and hydrolysable nitrogen(HN)significantly under Wa treatment,but average vegetation height and Shannon-Weiner index were positively correlated with soil pH significantly.Under SWa treatment,the mean height of plant community and Margalef index were negatively correlated with SMC significantly,and the mean height was positively correlated with soil pH significantly,the Margalef index was positively correlated with available phosphorus(AP)significantly.There was a significant positive correlation between Pileous index and AP under S treatment.Margalef index was negatively correlated with OC and HN significantly in control group.The results of this study revealed the response of alpine meadow plant community and soil nutrient to cli-mate change,

关 键 词：模拟增温 群落结构 加雪 土壤养分 纳木错 

分 类 号：S812[农业科学—草业科学]