2000年以来甘南植被变化趋势及原因分析  

Analysis of vegetation changing trends and causes in Gannan since 2000

作　　者：梁芸[1] 王大为[1] 

机构地区：[1]西北区域气候中心,甘肃兰州730020

出　　处：《草业科学》2016年第6期1102-1111,共10页Pratacultural Science

基　　金：国家自然科学基金"半干旱区大气边界层湍流相干结构对地表能量平衡的贡献"(41375019);甘肃省气象局科研项目"甘肃省典型区域生态环境监测研究"

摘　　要：归一化植被指数(NDVI)可表征植被生长状况,利用2000-2014年EOS/MODIS-NDVI及同期气温、降水资料、2000-2012年载畜量资料分析了甘南州植被时空变化及气象因子、人类活动对其影响。结果表明,1)近15年来,甘南整体植被稳定性呈增加趋势,林地稳定性大于草地,植被空间变异主要由草地的空间变化引起。2)15年来甘南州植被整体趋于好转,局部有显著减少趋势(P<0.05),研究区70%的区域植被呈增加趋势,21%的区域呈恶化趋势,恶化以草地为主,占总恶化面积的75%,主要分布在玛曲、碌曲及迭部。3)植被主要恶化区(玛曲、碌曲和迭部)气温有升高趋势;载畜量舟曲呈显著减少趋势(P<0.05),其它各县市均呈极显著增加趋势(P<0.01);载畜量逐年增加,过度放牧是引起甘南州局部植被趋于恶化、空间离散、分布不均的主要原因。The normalized difference vegetation index（NDVI）can characterize the vegetation growth status.The temporal and spatial changes of Ganan vegetation and of its response to climatic factors and human activities are analyzed using EOS/MODIS NDVI data,precipitation,temperature and stock capacity data during2000-2014.The results show that：1）The overall stability of vegetation takes on an increasing trend in recent15 years.The stability of forest is higher than that of grassland.The spatial variability of vegetation is mainly caused by the grassland.2）The vegetation tends to be improved and accounting 70% of the studying area.The decreasing trend（P〈0.05）happens only in a local place occupying 21% of total studying area.The decreasing is mainly owing to grassland degradation which contributes to 75%of the total degraded area.The degraded regions are primarily distributed in Maqu,Luqu and Diebu County.3）Temperature tends to increase mainly in degraded regions（Maqu,Luqu and Diebu）.The stock capacities show an extremely significant increasing trend（P〈0.01）except Zhouqu County,which has a decreased trend（P〈0.05）.The increasing stock capacity and overgrazing are the primary reasons caused the vegetation degradation,discrete,and nonuniform distribution.

关 键 词：甘南 植被变化 EOS-MODIS NDVI 

分 类 号：Q948[生物学—植物学]