延安丘陵沟壑区土地利用类型坡度分异研究  

Land Use and Slope Gradient Differentiation over Yan'an Hilly and Gully Area

作　　者：卓静[1] 邓凤东[2] 刘安麟[2] 周辉[2] 赵青兰[2] 

机构地区：[1]西北大学,西安710069 [2]陕西省农业遥感信息中心,西安710014

出　　处：《气象科技》2008年第2期219-222,261,共5页Meteorological Science and Technology

基　　金：国家科技攻关项目(2004BA522D07-1)"西北地区生态环境动态监测";"综合评价和应用服务系统研究"资助

摘　　要：选取典型黄土高原丘陵沟壑区的延安市宝塔区,利用遥感和地理信息系统技术,通过监督分类方法得到1997-2004年间该地区的土地利用分类图,并结合DEM（数字高程模型）坡度信息,分别提取1997年、2004年的坡耕地、坡林地、坡草地和坡园地数据,对该地区土地利用类型变化及坡度分异进行深入分析。结果表明：①在1997-2003年,耕地面积减少了33.1%,林地增加了10.1%、草地增加了20.6%、果园面积增加了33.3%,使该区域生态环境整体得到改善;②耕地减少的面积主要集中发生在坡耕地部分,其中坡度大于等于35°、25°-35°这两个等级减少的幅度最大,坡度大于等于35°减少了55.5%,25°-35°减少了51.2%,减少的坡耕地,基本上都是转变成了坡林地、坡草地、坡园地。耕地总面积减少的同时,基本农田（可灌溉）所占比例是增加的。该研究区＂退耕还林（草）＂工程的实施已经取得了初步成效。The land-use classification charts in 1997 and 2004 are acquired by means of the remote sensing, GIS, and supervised classification methods for the hilly and gully area （Baota district） in Yan＇an. Combined with the local DEM （digital elevation model） slope data, an analysis is made of the land-use distribution variation and differentiation with the data of the slope farmland, slope woodland, slope pasture and slope orchard for the years of 1997 and 2004. respectively. The results show that： （1） During the six years from 1997 to 2003, farmland decreased by 33.1%, woodland increased by 10.1%, pasture increased by 20.6%, orchard increased by 33.3% and the ecological environment of the studied area is improved generally. （2） The slope farmland decrease is mostly obvious, with the 55. 5% of decrease occurred in the area of %35% and 51.2% in 25% to 35%. The decreased slope farmland was mainly converted into slope woodland, slope orchard, and mostly the slope pasture. However, the proportion of the irrigable farmland to total farmlands increased while the total farmland decreased. Analysis shows that the preliminary achievements are attributed to the execution of the government＇s forestation project.

关 键 词：坡耕地 遥感 DEM 土地利用 

分 类 号：S792.116[农业科学—林木遗传育种] S157.1[农业科学—林学]