珠江口海岸带地貌特征对土地利用动态变化影响

Dynamic Change of Land Use in Coastal Zone of the Pearl River Estuary with Landform Analysis

珠江口作为我国经济发展最活跃的区域,受快速城市化与工业化影响,土地资源不断减少,出现耕地流失、恶性围填海等诸多问题。文中以珠江口海岸带为研究区,借助GIS和RS技术,应用Landsat ETM数据,结合实地考察资料,对1980―2010年珠江口的土地利用变化特征进行研究,并定量分析地形地貌因素对研究区土地利用变化的影响。研究结果表明:在过去近30a期间,研究区土地利用格局发生剧烈变化,耕地减少至原有量的42.1%,城镇用地增长了近8.5倍;土地利用变化受地形地貌因素影响显著,各土地利用类型转化主要发生在海拔130m以下地区,而在这一区间内,存在0～6m和20～80m两个活跃地段,分别是大规模围填海和城镇建设的分布区;对坡度而言,土地利用变化主要分布在0°～2°区间,在1980―2000年和2000―2010年两个时期土地利用类型转化量分别占总量的63.8%和76.2%。

During the course of fast economy development,accelerated urbanization and industrialization,the coastal zone of Pearl River Estuary is facing a series of problems：overloading of land resources carrying capacity,cultivated land decrease,wetland degradation and over sea reclamation.It is significant to promote the coastal land resources reasonable utilization.By extracting land use/cover information from Landsat ETM images with Gap-filled processing,the geomorphological background and the characteristics of land use/cover changes of the Pearl River Estuary were analyzed quantificationally.The results indicate that during the past three decades,landuse/cover in coastal zone of the Pearl River Estuary changed substantially.From 1980 to 2010,the total area of cultivated land was obviously reduced by 42.1% and construction land increased by almost 8.5 times.Changes of land use/cover types were affected by geomorphological features significantly.Landuse/cover changes mainly occurred at locations below 130 m,especially at locations between 0-6m and 20-80m.For slope degree,land use/cover changes mainly occurred at locations below 2°.The percentage of area of landuse conversion below 2°to the total was 63.8% during 1980-2000,and 76.2% during 2000-2010.