神府矿区土地利用与NDVI时空变化及其驱动因素分析

旨在研究矿区人类活动引起的土地利用变化及其对植被指数变化影响。以陕西省神府矿区为研究范围,应用线性趋势法和相关系数,结合土地利用和MODIS NDVI数据,分析了神府矿区土地利用与NDVI时空变化过程及其驱动因素。结果表明,2000—2010年神府矿区土地利用变化特征表现为耕地大面积转为草地和建设用地迅速增加。2000—2015年神府矿区NDVI总体呈线性增加趋势,线性增加速率为0.105/10a(P<0.001)。NDVI显著增加区域占矿区总面积的95.95%,仅有河流谷地、城镇附近区域NDVI呈减少趋势。耕地面积下降和建设用地面积扩张,导致NDVI降低,草地和林地面积增加,引起NDVI升高。神府矿区2000—2015年NDVI与气温以负相关为主,与降水以显著正相关为主,占区域总面积的97.79%,负相关以斑块状和线状集中在城镇附近和河流谷地。研究认为退耕还林还草工程实施和社会经济发展引起的城市扩张是神府矿区土地利用变化的主要驱动因素,而气候变化尤其是降水增加和草地、林地面积增加有力促进了NDVI的升高。

Land Use and Spatial and Temporal Change of Normalized Difference Vegetation Index (NDVI) in Shenfu Mining Area and Their Driving Factors Analysis

The aim is to study land use changes caused by human activities in mining areas and their impact on vegetation index changes. Taking Shenfu mining area in Shaanxi Province as the research scope, combing with the comprehensive land use and MODIS NDVI data, the temporal and spatial variation process and driving factors of land use and NDVI were analyzed with linear trend method and correlation coefficients. The results showed that the characteristics of land use change from 2000 to 2010 were the conversion of large areas of farmland to grassland and rapid increase of construction land. From 2000 to 2015, NDVI showed a linear increase trend and the linear increase rate was 0.105/10a (P<0.001). The NDVI significantly increased area accounted for 95.95% of the total area, while only the river valley and the area near the town showed a decreasing trend. The decline area of farmland and the expansion area of construction land led to the decrease of NDVI, but the increase area in grassland and woodland resulted in the increase of NDVI. NDVI from 2000 to 2015 was mainly negatively correlated with temperature, and was significantly and positively correlated with precipitation, accounting for 97.79% of the total area. The negative correlation was concentrated in the vicinity of towns and river valleys by plaques and lines. The study indicates that urban expansion caused by social and economic development and the grain for green project implementation are the main driving factors for land use change in Shenfu mining area, and climate change, especially the increase of precipitation and the increase of grassland and forest land area, has promoted the increase of NDVI.