黄河三角洲滨海盐碱退化土地变化遥感监测研究

以黄河三角洲垦利县为研究区,采用1987年5月7日和1998年5月5日陆地卫星TM遥感影像以及2005年4月13日中巴资源卫星影像数据,对遥感影像进行图像预处理.根据各地类光谱特征,以决策树分类方法剔除非盐碱地类信息,构建土地退化指数模型,获取研究区土地退化等级分布信息并分析其空间变化.结果表明,1987～2005年,研究区重度退化土地比例由12.7%增加为20.5%;中度退化土地由39.5%降至18.2%;轻度退化土地等级由17.7%上升为40.2%;无退化土地则由30.1%下降为21.1%,总体呈现为重-轻-重的动态变化趋势.提出滨海盐碱土地信息遥感提取技术方法,为黄河三角洲土地资源的可持续利用和保护提供理论和决策依据.

A Study of Remote Sensing Detection of Salt-affected Coastal Land Degradation in the Yellow River Delta

Kenli County in the Yellow River Delta was chosen as the study area,the two TM digital ima-ges obtained on May 7,1987 and May 5,1998,and one CBERS digital image obtained on April 13,2005 were preprocessed.Based on the systematic analysis of all the spectrum features,the apparent information of non-salt-affected was eliminated by using a classification method of decision-making.An index model of land degradation and extracted gradient distribution information of land degradation in the study area was built.Fur-thermore,the dynamic situation land degradation Was delineated.The results showed that during the period from 1987 to 2005,the percentage ofthe heavy degradation land in the study area had suffered an increase of 12.7%～20.5%,the moderately degraded land decreased from 39.5%to 18.2%,the lighdy degraded land increased from 17.7%to 40.2%.and the non-degradation land decreased from 30.1%to 21.1%,unfol-ding a dynamic change tendency of heavy-light-heavy.This study has provided a method of remote sensing information extraction and decision-making basis for the sustainable utilization and protection of land re-sources in the Yellow River delta.