基于遥感和像元二分模型的新疆植被覆盖度格局动态监测

利用MODIS归一化植被指数(NDVI)资料反演了2006—2015年新疆植被覆盖状况,获取不同时期的植被覆盖度图,并进一步分析了植被覆盖度变化的原因。结果表明:新疆植被覆盖度呈现北部高于南部、西部高于东部的分布特征,其中西部和西北部的山地森林、草地以及天山北坡绿洲农作物、草地区域植被覆盖情况最好。过去10年间,新疆植被覆盖度总体呈上升趋势,2015年植被覆盖度达到最高,为16.68%。生态恢复工程、降水和气温等是影响植被覆盖度变化的主要因素。     

阿图什市"十五"期间土地利用变化及分析

利用2001-2005年的遥感影像数据(覆盖范围主要是克孜勒苏柯尔克孜自治州行政辖区内的阿图什市),通过统计2001-2005 年土地利用数据,分析了该市近五年土地利用/覆盖的时空变化规律,并进而探究了导致该变化发生的自然、人文驱动因素.结果表明:在2001-2005年,该区域林地和草地面积增加,耕地面积减少,土地沙化和盐碱化现象得到遏制.探其原因主要是由社会、经济等人文因素造成,而包括气候波动在内的自然条件只是土地利用变化的背景条件.     

基于RS和GIS技术的贵州省植被生态环境监测分析

为阐明贵州省植被生态环境变化的整体状况,基于RS和GIS技术,应用美国国家航空航天局最新的全球植被指数变化研究数据（GIMMS）,通过计算月归一化植被指数（NDVI）变化率,并对研究区一元线性回归模拟,分析了贵州省1982年-2003年的地表植被覆盖。结果表明：22年来,研究区植被覆盖呈增加趋势,表明贵州省植被生态环境向好的方向发展;贵州省平均植被覆盖在春季和秋季呈上升趋势,夏季和冬季呈下降趋势,其中春季对植被覆盖总变化量的贡献最大;植被覆盖程度增减因区域不同而异,变化程度呈增加的区域主要位于贵,ki-I省的中部地区;变化程度呈减小的区域分布在贵州省的四周边缘。     

近期我国生态环境状况变化趋势分析研究

利用2000年和2005年遥感监测数据及相关统计数据,从生物丰度、植被覆盖、水网密度、土地退化和环境质量五个方面综合评价近五年来我国的生态环境变化趋势,并分析生态环境状况的变化与生物丰度指数等五个因子之间的相关关系.该评价不包括香港特别行政区、澳门特别行政区和台湾省.     

20年间艾比湖流域植被覆盖度景观格局变化

选取艾比湖流域1990年、2001年、2011年同期（9月）3期I．and．satTM遥感影像,基于归一化植被指数NDVI,提取植被覆盖等级图,利用ArcGIS9．3和Fragstas3．3对该流域植被景观的变化进行了分析研究。结果表明：1990—2011年,该流域植被覆盖度变化明显,低植被覆盖区和较低植被覆盖区都有所减少,分别由1990年的34．05％和32．94％减少到2011年的32．8％和24．06％;较高植被覆盖区和高植被覆盖区有所增加,分别由8．49％和5．20％增长到15．13％和9．83％,但水域面积退化明显,由1990年的525．9765km2缩小至494．9876km2,减少了30．9889km2,退缩幅度达O．4％;最大斑块指数（LPI）由17．04上升到21．10,香农多样性指数（SHDI）和香农均势度指数（SHEI）分别由1．5387和0．8588增长到1．6395和0．9150。表明艾比湖流域景观格局混杂程度愈来愈高,空间异质性在逐年加强,总体空间格局向破碎化趋势发展。     

基于神东中心区植被覆盖变化的多时相遥感监测

准确、快速地获取植被覆盖信息是矿区生态恢复和建设的关键与重点。以神东中心区为研究对象,利用2002、2005、2007、2010、2012年Landsat TM/ETM+和HJ1A-CCD1五景同期遥感数据,采用像元二分模型法,归一化植被指数(NDVI)值反演植被覆盖度,对研究区生态环境变化规律进行分析。结果表明,神东中心区平均植被覆盖度整体呈上升趋势,区内绝大部分地表覆盖程度得到改善,改善区面积达64.01%,退化区面积只有15.34%。该方法快速、定量地反映矿区植被覆盖及变化情况,为矿区生态环境动态监测和治理提供技术支持。     

基于RS-GIS伊犁河谷土地利用-土地覆盖变化研究

解译2000和2005年伊犁河谷的Landsat TM遥感影像,分析和探讨土地利用-土地覆盖现状和动态变化及其特征.结果表明,伊犁河谷土地利用总体程度低,土地利用过程还处于发展阶段,土地利用-土地覆盖面积变化显著,由此引起的生态环境问题也日益明显.     

基于RS和GIS的干旱荒漠区域土壤侵蚀动态监测与评价

为建立土壤侵蚀动态变化数据库,本文以土地利用数据、植被覆盖指数、最大风速等值线图和DEM数据为信息源,对干旱荒漠区新疆克拉玛依市2000年和2007年的土壤侵蚀状况进行了动态监测与评价。结果表明,受自然条件和人类活动影响,8年间克拉玛依市土壤侵蚀强度有所增加,变化区域主要集中在克拉玛依市中部平原区。该方法的应用实现了土壤侵蚀的定时定量评价。     

新疆伊犁州2000～2005年生态环境质量变化评价与分析

利用Landsat-5 TM遥感影像解译的土地利用数据分析了新疆伊犁州(州直辖)2000～2005年的土地利用变化,同时根据<生态环境状况评价技术规范>(试行)(HJ/T192-2006),对该区域生态环境质量状况进行综合评价,对生态环境指标变化情况进行对比分析.结果表明,2000～2005年伊犁州的生态环境质量均为一般,生态环境质量指数(E1)减少0.71.主要原因为草地面积明显减少,耕地面积明显增加.     

塔里木河下游植被指数的遥感监测

为了了解塔里木河下游9次应急输水的生态环境效益,利用MODIS—NDVI最大合成法、差值法,分析了塔里木河下游植被指数的年际变化情况,结果表明：（1）塔里木河下游地区植被覆盖度变化中增加区面积呈增加趋势。（2）2002年与输水初期相比,植被覆盖度增加区主要分布于上段和中段的老塔里木河及其文阔尔河河道两侧,下段河道覆盖度增加区仅零星分布于距河道0．3km左右的地势低洼区域。2003年以后,下段植被覆盖度增加区面积已达84．30km^2,是2002年的3．16倍,主要分布在距离河道0．5km左右的河道两侧。至2007年塔里木河下游河道两侧植被覆盖度增加区的变化是比较显著的,特别是下段植被覆盖增加区呈带状分布于距河道1．5km左右的范围内。植被指数遥感监测说明塔里木河下游地区的生态环境得到明显改善。     

Vegetation coverage change and associated driving forces in mountain areas of Northwestern Yunnan, China using RS and GIS

The dynamics of vegetation coverage and associated driving forces are one of the key issues in global environmental change. In the study, taking Lijiang County as a case, the Normalized Difference Vegetation Index was used to quantify vegetation coverage change in mountain areas of Northwestern Yunnan, China, with the application of remote sensing data and GIS technologies. And associated driving forces of vegetation coverage change were also analyzed, with a focus on land use change and elevation. The results showed that there was high vegetation coverage with a significant increase in the whole county during 1986-2002. However, due to economic development and the implementation of environmental protection polices, vegetation coverage change in the county showed distinct spatial diversity, which mainly behaved as the increasing in the northwest of the county with low human activities, and the decreasing in the south with high economic development. The results also showed that as a restrictive factor, elevation was of great signification on the spatial distribution of vegetation coverage in a broad scale; while in the county level, it was land use that determined the vegetation coverage, since the change of vegetation coverage grades in the study area was mainly associated with the change of land use types.     

应用遥感监测技术分析扬州市五年植被覆盖状况

利用扬州市2006—2010年间卫星遥感数据,对扬州市植被覆盖状况进行了研究。首先对遥感影像进行几何校正,其次对遥感影像进行解译,提取植被覆盖信息,计算扬州市植被覆盖指数,同时对扬州市近5年植被覆盖进行了动态变化分析。研究表明,扬州市近5年林地面积大幅度提高,植被覆盖指数逐年增加,生态环境状况逐年好转。     

Analysis of the changes of vegetation coverage of western Beijing mountainous areas using remote sensing and GIS

Mentougou District acts as a crucial component in the ecological buffer in western Beijing mountainous areas, Beijing, China. Using two Landsat MSS/TM images acquired on July 14, 1979 and July 23, 2005, the vegetation coverage of Mentougou District was calculated based on normalized difference vegetation index and spectral mixture analysis (NDVI-SMA) model. Its temporal and spatial changes were analyzed according to digital elevation model (DEM) image, social and economic data. The results showed that the vegetation coverage decreased from 76.4% in 1979 to 72.7% in 2005. Vegetation degradation was probably the result of human disturbance, such as outspreading of resident areas, and coal and stone mining activities, while vegetation restoration might be contributed by the combined effects of both natural processes and ecological construction effort. Vegetation changes were closely related to topographical characteristics. Plants at high altitude were more stable and less degraded than the plants at low altitude, while the plants on steep slope or northwest aspect were more vulnerable to degradation. During the period of 26 years, landscape appeared to become more fragmental, and ecological quality of the land seemed deteriorated sharply in that highly-covered vegetation area has been decreased by 24%.     

Estimation of Vegetation Coverage in Semi-arid Sandy Land Based on Multivariate Statistical Modeling Using Remote Sensing Data

The estimation of vegetation coverage is essential in the monitoring and management of arid and semi-arid sandy lands. But how to estimate vegetation coverage and monitor the environmental change at global and regional scales still remains to be further studied. Here, combined with field vegetation survey, multispectral remote sensing data were used to estimate coverage based on theoretical statistical modeling. First, the remote sensing data were processed and several groups of spectral variables were selected/proposed and calculated, and then statistically correlated to measured vegetation coverage. Both the single- and multiple-variable-based models were established and further analyzed. Among all single-variable-based models, that is based on Normalized Difference Vegetation Index showed the highest R (0.900) and R ² (0.810) as well as lowest standard estimate error (0.128024). Since the multiple-variable-based model using multiple stepwise regression analysis behaved much better, it was determined as the optimal model for local coverage estimation. Finally, the estimation was conducted based on the optimal model and the result was cross-validated. The coefficient of determination used for validation was 0.867 with a root-mean-squared error (RMSE) of 0.101. The large-scale estimation of vegetation coverage using statistical modeling based on remote sensing data can be helpful for the monitoring and controlling of desertification in arid and semi-arid regions. It could serve for regional ecological management which is of great significance.     

丹江湿地国家级自然保护区及其内外区域2000—2015年土地覆被变化分析

为研究2000—2015年丹江湿地国家级自然保护区及其内外生态状况变化和保护成效,基于高分1号数据生产的2m高分辨率遥感影像数据对丹江湿地国家级自然保护区2015年人类活动状况进行分析,基于30 m分辨率的4期TM遥感影像生产的土地覆被数据和基于Modis遥感影像生产的植被覆盖度数据,对淅川县、丹江湿地国家级自然保护区及其核心区的土地覆被状况、土地覆被转类指数及其土地覆被转类途径的主导程度和3个相关区域范围内的生态系统质量以及不同区域土地覆被变化的主要变化原因进行分析。结果表明,保护区核心区的格局和质量在该区域处于最优,且土地覆被变化状况也以核心区转类指数最高;丹江湿地国家级自然保护区内的主要人类活动影响为耕地,其次包括居民点、采石场、养殖场; 15年间,保护区内外土地覆被均呈现转好趋势,但是保护区内变化优于保护区外,保护区核心区优于整个保护区,且转好的主导因素均是耕地变为湿地; 15年间植被覆盖度变化较小。     

生态修复工程实施后对土壤理化性质改善效益初探

通过监测和田地区生态修复项目实施后所取得生态效益的结果表明,生态修复项目实施后,由于项目区风速降低,温度和相对湿度的变化减少,提高了植被盖度,降低了风蚀量,促进了成土作用的进行,从而逐渐改善了土壤的理化性质。