摘要
本文基于1998年-2007年中国地区长时间序列SPOT_Vegetation植被指数数据集,应用RS与GIS技术,采用最大值合成、一元线性回归变化斜率法和Mann-Kendall非参数检验法对中国各大自然区划(3个大类、7个中类)的植被覆盖状况做了时空变化分析。结果表明:基于SPOT_Vegetation植被指数数据可以很好的在宏观上监测中国的植被覆盖时空变化,1998年-2007年,中国整体上植被活动在增强,并向好的方向改善,特别是东部季风区域中华中、华南湿润亚热带地区,东北湿润、半湿润温带地区和华北湿润、半湿润暖温带地区植被覆盖显著上升。但局部在却在恶化,西北干旱区域特别是内蒙古中西地区产生严重的恶化。近1/3国土面积植被覆盖基本不变。且斜率变化法和Mann-Kendall非参数检验法可以相互印证,对中国的植被覆盖状况,时空变化有着基本一致的判断。
Vegetation is one of the most important land covers on the Earth;its change can have a significant impact on the global energy and material cycles.In particular,spatial and temporal variations in vegetation cover is of great significance to understand global change.Large-scale monitoring of vegetation changes became possible since the advent of satellite remote sensing.In order to reveal the dynamic vegetation change in China during the recent decade,we investigated the similarities and differences in vegetation change across major natural regionalization of China.Characteristics of the vegetation changes were comprehensively explored and summarized.A SPOT vegetation time series during the period 1998-2007 was made use of in this study.This data set is a subset of China＇s data set of the SPOT vegetation date set,including 10-day composite of spectral reflectances of four visible and near-infrared bands and 10-day maximum NDVI data set during the period 1998-2007 with a spatial resolution of 1 km.The temporal resolution is ten days.Imageries preprocessing consisting of atmospheric and geometric corrections were performed,and 10-day maximum values of the NDVI time series were derived.Methods of the Maximum Value Composites（MVC）,slope of the linear regression,Mann-Kendall non-parametric test,as well as nature zoning status of the vegetation cover were used to unravel spatial and temporal changes in vegetation.The MVC method can further eliminate effects of cloud contamination,the atmosphere,and solar elevation angle.Results show that the SPOT vegetation index time series appears to be a promising indicator of large-scale monitoring of spatial and temporal changes in vegetation cover in China during the last decade.In general,the vegetation across the country increased to varying degrees,and the health statues was improved as well.In particular,marked increases in vegetation cover occurred over the eastern China monsoon region,the southern China wetting subtropical regions,the northeastern humid and semi-humid temperate regions,and northern humid and semi-humid warm temperate regions.However,the vegetation and its status were found to be deteriorating in part across the northwestern arid region and central and western Inner Mongolia.Vegetation conditions of nearly 1/3 of the country remained essentially invariant during the study period.
出处
《资源科学》
CSSCI
CSCD
北大核心
2011年第2期335-340,共6页
Resources Science
基金
陕西省"13115"科技创新工程重大科技专项项目(编号:2008ZDKG-75)
西北大学研究生创新基金(编号:08YZZ27)
