综合目视解译和计算机自动解译的方法,将冰川解译的传统方法及面向对象图像特征提取方法应用于喀纳斯河源的冰川边界提取中,并对提取出的单条冰川逐一分析。研究发现:面向对象的图像特征提取方法能较好的提取具有特征类型的地物;目视解译的方法虽然费时费力,但适用于任何类型冰川的提取;传统比值阈值、雪盖指数法、监督分类与非监督分类在无表碛覆盖,积雪覆盖较少的纯冰区效果明显。对阿尔泰山喀纳斯河源区的40条冰川进行解译,对多种方法进行比较,得到喀纳斯河源地区精确的冰川边界。结果表明:喀纳斯河源区冰川总体上呈退缩趋势,1959—2011年冰川面积共减少了23.43 km^2。
In this paper, the manual digitization method and computer automatic grated, and the traditional method of glacier interpretation and the object-oriented were applied to extract the glacier boundary in headwaters of the Kanas River. interpretation method were inteimage feature extraction method Through the application, it was found that: (1) Human interpretation could be the best tool for extracting high-level information from satellite imagery for many glacier types; (2) Classification methods based on threshold band ratios or normalized band differences like NDSI were proven to be accurate and as the robust methods for interpreting clean glacier ice, but they may lead to errors for the glaciers covered by surface moraine; (3) The object-oriented method could be used to extract the surface features, and its accuracy was high in extracting glacier information, especially the disturbance of cloud and snow cover could be restricted ; (4) The classification method of automatic threshold decision tree needs to be further studied ; (5) An interpretation of 40 glaciers in headwaters of the Kanas River was carried out, the various methods were compared, and the values of precise glacial boundary were derived. The results showed that the glaciers in headwaters of the Kanas River were holistically in a retreat trend, and their area was reduced about 23.43 km^2 during the period of 1959 - 2011.