2001-2020年内陆干旱草原县域尺度植被NDVI时空变化特征及其驱动因素  

Spatio-temporal Variation Characteristics and Its Driving Factors of NDVI at County Scale for an Inland Arid Grassland During 2001-2020

作　　者：胡志强 宋孝玉[1] 覃琳 刘辉[1] 文望 Hu Zhiqiang;Song Xiaoyu;Qin Lin;Liu Hui;Wen Wang(State Key Laboratory of Eco-hydraulics in Northwest Arid Region of China,Xi’an University of Technology,Xi’an,Shaanxi 710048,China)

机构地区：[1]西安理工大学省部共建西北旱区生态水利国家重点实验室,陕西西安710048

出　　处：《水土保持通报》2022年第5期213-221,共9页Bulletin of Soil and Water Conservation

基　　金：国家重点研发计划项目“西部牧区草地生态水-草-畜平衡与水资源优化配置技术研究”(2016YFC0400301)。

摘　　要：[目的]探讨中国内陆干旱草原在县域尺度上时序地表生态空间变化及气候驱动特征,为制定合理的生态措施提供科学依据。[方法]以甘肃省肃南县(肃南裕固族自治县)为研究区,收集归一化植被指数(NDVI)和气象数据,采用趋势分析、变差分析、偏相关分析和残差分析等方法,分析了2001-2020年肃南县植被NDVI时空变化特征及驱动因素。[结果]①研究期内县域植被NDVI呈波动上升趋势,上升速度为0.042/10 a;10种植被的NDVI呈现相似的增长趋势,较以往小尺度区域研究能够作出更精确的反映;②从空间分布看,植被NDVI自西北向东南逐渐提高,全县36.14%的植被NDVI变化趋势表现为基本稳定,退化区域远大于改善区域;③肃南县不同类型植被对植被NDVI稳定性的贡献程度为:针叶林>灌丛>阔叶林>草原>草甸>高山植被>栽培植被>其他>沼泽>荒漠;④植被NDVI受夏季降水量及植物生长季气温影响最大,人类活动对肃南县96.52%的植被NDVI增加具有促进作用。[结论]近20年来,肃南县植被NDVI整体上升,其变化趋势受气候条件和人类活动的双重影响,未来肃南县过度放牧区域植被NDVI可能仍会下降,但整体依旧呈上升趋势。[Objective]The temporal surface ecological spatial changes and climate-driven characteristics of China’s inland arid grassland at the county scale was determined in order to provide a scientific basis for the formulation of reasonable ecological measures.[Methods]This study was conducted in Sunan County(Yugu Autonomous County of Sunan),Gansu Province.Normalized difference vegetation index(NDVI)and meteorological data were collected and analyzed to determine the characteristics and driving factors of the temporal and spatial changes of vegetation NDVI in Sunan County from 2001 to 2020 using trend analysis,variation analysis,partial correlation analysis,and residual analysis.[Results]①During the study period,NDVI for the county showed a fluctuating upward trend,with a rising rate of 0.042/10 yr.In addition,the NDVI of the 10 vegetation types showed a similar growth trend that was reflected more accurately than in previous small-scale regional studies.②NDVI gradually increased from northwest to southeast.The NDVI variation trend was basically stable in 36.14%of the area of Sunan County,while the degraded area was much larger than the improved area.③The contribution degree of the different vegetation types to NDVI stability in Sunan County followed the order of coniferous forest>scrublands>broadleaf forest>steppe>meadow>alpine vegetation>cultivated vegetation>others>swamp>desert.④NDVI was most affected by summer precipitation and plant growing season temperature.Human activities had a facilitating effect on 96.52%of the vegetation NDVI in Sunan County.[Conclusion]Overall,the vegetation NDVI of Sunan County has increased over the past 20 years,and its change trend was influenced by both climatic conditions and human activities.In the future,vegetation NDVI in the overgrazed areas of Sunan County may continue to decline,but the overall trend will be increasing.

关 键 词：植被 内陆干旱草原 NDVI时空变化 驱动因素 甘肃省肃南县 

分 类 号：Q948.112[生物学—植物学]