龙口市海岸带土地利用动态变化分析

Analysis of the dynamic change of land use in Longkou city's coastal zone based on remote sensing technology

利用多期遥感数据,采用目视解译和人机交互计算机分类技术提取1984至2004年间龙口市海岸带土地利用信息,从土地利用总量变化、土地利用变化速度、土地利用类型之间的相互转化、土地利用类型变化的海岸区位效应等方面分析龙口市海岸带动态变化特点。研究结果表明,20年间龙口市海岸带一半以上的土地类型发生了变化,变化速度逐年增加,后期明显大于前期;转化方向上主要表现在耕地向园地的转化,其次是耕地、园地、林地向建设用地的转化;变化的区位特征是距海越近,海岸带特征地类的变化越明显,反之,距海越远,内陆土地利用变化的特点表现得越突出。

The coastal zone is the geographical unit where human activate most intensely. In recent years, with the rapid development of economy, the resources and environment of coastal zone have been greatly damaged due to the unreasonable utility of land resource. So the study on dynamic monitoring of the land use changes in coastal zone has became a hot topic of global changes. This paper uses the multi-time remote sensing data, integrates spectral values, texture data with the distance from coastline by BP Neural Network classifier, adopts visual interpretation and user interface computer classification technology to abstract the coastal zone land use information of Longkou city from 1984 to 2004. It analyzes the dynamic change characteristics of Longkou city＇s coastal zone on the aspects of land use total quantity change, land use changing rate, mutual transformation of land use types, coastal location effect of the change of land use types, and so on. The findings indicate that during the 20 years more than half of the coastal zone＇s land types in Longkou city have changed. There was a great decrease in sandy land and cultivated land and a remarkable increase in water area, orchard land and construction land; the rate of the land use change was up to 1.53% per year, the period of 1996-2000 saw obviously larger changing rate than that of the period before and after, and water area changed at the highest rate among all land-use types. Concerning conversion degree, cultivated land conversion to orchard land, occupies the greatest proportion, distributing extensively in both northern and western coastal zone; cultivated land convered to construction land comes the second distributing obviously in the western coastal zone due to southward expansion of Longkou, and the construction land converted from orchard and forest lands are distributed mainly in the northern part of the Longkou port and the Northern Sea Developing Zone of the Nansban Group. However, the active land-use conversion was the sandy land turning to other land-use types in the region in a distance less than 500 m from the coastline. So the characteristic of the locational change is that the nearer to the sea, the more obvious the change of the coastal zone characteristic land-use type. On the contrary, the farther from the sea, the more prominent the characteristic of the inland land-use change presents.