利用遥感信息监测宁南县县域石漠化及石漠化发展趋势分析

研究县域石漠化的空间分布特征,分析其发展趋势。以宁南县为例,首先运用遥感(remote sensing,RS)和地理信息系统(geographic information system,GIS)技术提取2005年和2015年两期的石漠化范围并分级;其次,将提取结果分别与坡度、坡向、河流、人口数据叠加,分析石漠化空间分布特征;最后利用马尔科夫模型对宁南县未来10年石漠化的发展趋势进行预测。研究表明:宁南县2015年重度、中度石漠化面积较2005年有所减少;潜在、轻度石漠化面积有所增加,分别增加3. 9%和1. 7%;重度、中度石漠化主要分布在黑水河、金沙江流域,人口密度大于120人/km~2的区域,且坡向偏南、偏东,坡度为缓坡、缓陡坡。根据预测结果,2025年,重度、中度、轻度、无石漠化面积减小,潜在石漠化面积增加。研究为西南地区石漠化治理与重点防治以及其他地区石漠化监测及预测提供了参考。

Using Remote Sensing Information to Monitor County Rocky Desertification and Development Trends in Ningnan County

In order to study the spatial distribution characteristics of stony desertification and analyze its development trend in counties. Take Ningnan county as an example, firstly, Remote Sensing (RS) and Geographic Information System (GIS) were used to extract and classify the stony desertification areas in 2005 and 2015. Secondly, the spatial distribution characteristics of stony desertification were analyzed by combining the extracted results with slope, slope direction, river and population data. Finally, the Markoff model is used to predict the development trend of stony desertification in the next ten years. The research shows that ,the heavy and moderate areas of Ningnan county decreased in 2015 compared with 2005, and the area of potential and mild stony desertification increased by 3.9% and 1.7% respectively. Moderate and severe stony desertification is mainly distributed in the Heishui River and Jinsha River basin. The population density is greater than 120 people/km2, and the slope is south and East, and the slope is gentle slope and gentle slope is also the main distribution area. According to the prediction results, in 2025, the area of severe, moderate, mild and non-stony desertification decreased, and the potential stony desertification area increased. This study provides a reference for stony desertification control and key prevention and control as well as monitoring and prediction of rocky desertification in other areas of Southwest China.