中文摘要：

以高空间分辨率、高光谱分辨率CASI航空遥感数据作为采样带，对黑河中游绿洲灌溉区土地覆盖和农作物种植结构空间格局进行遥感监测。设计了分层分类方法，综合采用基于像素和基于对象的2种遥感图像分类方法对航空样带区域进行土地覆盖制图。根据实地土地覆盖类型调查与目视解译，对样带土地覆盖和农作物种植结构的分类结果进行精度评价，总体分类精度为84．2％，Kappa系数为0．793。与样带区域2007年Landsat TM，／ETM＋土地覆盖产品相比，高分辨率cAsI航空数据能够对树木、草地与农作物类别进行有效监测。监测结果表明，中游绿洲灌溉区内接近59．1％的地区为裸地与建筑用地；植被覆盖区域占39．8％，其中，农田34．9％，树木5．3％，草地仅有0．1％；而在农田区域中玉米为大宗作物，分类成数占96．1％。研究结果表明高质量与高分辨率的航空遥感数据能够实现对流域下垫面异质性进行有效监测，为生态一水文过程研究提供高分辨率的下垫面类型信息。

英文摘要：

The land cover pattern and crops structure of oasis irrigation area of middle reaches in the Heihe River Basin were monitored using CASI aerial data with high spatial and spectral resolution as transects. We designed a hierarchical classification structure integrated by pixel-based classification and object-based classification to map land cover types and crop planting structure in this region. According to surveyed reference data about land cover and visual interpretation from high resolution imagery, the accuracy of the classification result about land cover and crops pattern from CASI transect data was evaluated, and the result showed that overall accuracy was 84. 61% , Kappa coefficient was 0. 8262. Compared with landsat TM/ETM＋ land cover product in Zhangye in 2007 within flight transects, CASI aerial data with high resolution was able to effectively identify the trees, shrubs and various crops. Land cover pattern of oasis irrigation area and various crop proportions within cropland area were analyzed using CASI classification result. The result showed that almost 59, 1% of oasis irrigation area of middle reaches in the Heihe River Basin was barren or built-up region, and vegetated region accounted for 39.8%. Cropland, trees and grassland accounted for 39.4% , 5.3% and 0. 1% respectively, and corn was staple crop, accounting for 96.1% within cropland area. This study demonstrated that aerial remote sensing data with high quality and high spatial resolution was able to effectively monitor spatial heterogeneity of underlying surface in the basin, and offer high-resolution information about underlying surface types for study on eco-hydrological process,