基于Landsat-X GEVI的贵州纳雍地区2003-2015年岩溶石漠化分布变化遥感调查

Remote sensing investigation to the distribution and change of karst rocky desertification from 2003 to 2015 in the Nayong area of Guizhou based on Landsat-X GEVI

岩溶石漠化是困扰中国西南岩溶地区发展的一种脆弱的生态环境,为了解贵州纳雍地区岩溶石漠化的改善情况,基于Landsat数据利用改进增强型植被指数模型(GEVI)方法提取了2003年和2015年的岩溶石漠化信息,分别为540.06 km^2和390.99 km^2,并将两期岩溶石漠化信息进行叠加分析和对比研究,发现该地区岩溶石漠化面积减少了149.07 km^2,改善率(减少率)达12.88%,尤其是原成片分布的石漠化区域(如朝阳谷、滥坝和猫场等地)多呈碎斑状缩小,且发现研究区岩溶石漠化位置有自南西向北东迁移的现象,迁移面积为289.47 km^2,以中度岩溶石漠化为主,说明治理与破坏同步,防治形势仍很严峻,但岩溶石漠化总面积减少,生态状况呈良性发展态势,反映出近年来综合治理成效显著。

Karst rocky desertification is a fragile ecological environment that puzzles the development of karst areas in southwest China.In order to understand the improvement of karst rocky desertification in the Nayong area of Guizhou,the authors extracted the scale information of karst rocky desertification in 2003 and 2015 by using the improved enhanced vegetation index model(GEVI)method based on Landsat data,which is 540.06km^2 and 390.99 km^2,respectively.Comparison of data over these two periods shows that the area of karst rocky desertification in this area has been reduced by 149.07 km^2,and the improvement rate has reached 12.88%,especially in the areas of severe rocky desertification(such as Chaoyanggu,Lanba and Maochang),which have been distributed in vast swaths previously.It is also found that the karst rocky desertification in this area is migrating from southwest to northeast,with an area of 289.47 km^2,dominated by a moderate degree.It indicates that the control and destruction are synchronized,and the control task remains a great challenge.Nevertheless,the total area of karst rocky desertification is reduced and ecological conditions show a benign development trend,reflecting the effectiveness of comprehensive efforts in recent years.