重庆“一小时经济圈”土地利用变化的海拔梯度特征

The Characteristics of Land Use Change in Different Altitude Gradient of "One-hour Economic Circle" of Chongqing Metropolis

采用重庆"一小时经济圈"1994、2000、2006年3期遥感影像解译数据,分析了1994—2000年、2000—2006年不同海拔梯度(≤400m、400—800m、800—1200m和≥1200m)土地利用变化的时空特征.400m以下区域是土地利用变化最剧烈的区域,1994—2000年,高海拔地区(400m以上区域)的耕地(旱地和水田)大量转化为林草地,而400m以下区域地势相对平坦的其它土地利用类型大量转化为耕地;2000—2006年,耕地(旱地和水田)大量转化为草地和居民点及工矿用地.重庆"一小时经济圈"各海拔梯度土地利用变化速率呈现波动特征,但就两个时段相同海拔区域土地利用变化速率看,各海拔梯度土地利用变化速率均是一个不断减小的过程,1994年以来全区域的土地利用程度经历了一个不断降低的过程.通过重庆"一小时经济圈"不同时段和不同海拔梯度土地利用变化的时空特征分析,有助于理解后备资源短缺和快速城市化条件下的土地资源压力,对制定该区域合适的土地管理时空策略具有重要意义.

Base on the economic circle＂ altitude gradient （ multi-temporal remotely sensed data of 1994,2000 and 2006 in ＂one-hour of Chongqing, the characteristics of land use change were analyzed in various ~〈400m,400--800m,800--1200m and ≥ 1200m）. The land use changed rapidly in the area into woodland and blew 400m and from 1994 to 2000, large numbers of cropland transformed grassland in high altitude area（ above 400m）. While in relatively flat areas blew 400m, lots of other land use types changed into cropland. From 2000 to 2006, a great number of cropland were used for grassland, settlements and industrial land. The ratio of land use change was fluctuant in different altitude Chongqing. But from the ratio of land use change gradient of ＂ one-hour economic circle＂ of in the same altitude gradient between the two periods ,we could find that the ratio of land use change in various altitude gradient and the intensity of land use in the whole area was decreasing from 2004. Therefore, the analysis of characteristics of land use change in various period and altitude gradient was beneficial for understanding the pressure on land resources due to scarce exploitable resources and rapid urbanization and then publishing suitable land management policies for this area.