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欧科范果三角洲地区泛滥范围年年在变化。这种变化与安哥拉高地集水区的区域性降水及当地降雨量有关。我们采用了1972～2000年的3000多幅卫星图像来描绘湿地的格局,其中从1985～2000年的图像几乎是NOAAAVHRR每日连续传送的,1972年以来的其它图像是从Landsat传感器上传下来的,其连续性次之。对AVHRR图像每10天为一期,用无监督分类方法分成陆地和水体。对LandsatTM和ERS2-ATSR数据进行分析的结果,与测算的淹没区域89%相吻合。结果显示欧科范果湿地近期30年期间的变化约在2450～11400km~2之间。
The extent of flooding in the Ochota-Kashmir delta is changing year after year. This change is related to the regional precipitation and local rainfall in the catchment of the highlands of Angola. We used more than 3,000 satellite images from 1972 to 2000 to characterize the pattern of the wetlands. The images from 1985 to 2000 were almost continuously transmitted daily by the NOAA AVHRR. Other images were uploaded from Landsat sensors since 1972, Its continuity is second. AVHRR images are taken every 10 days and are classified as land and water by unsupervised classification. The results of LandsatTM and ERS2-ATSR data analysis coincide with 89% of the estimated submerged area. The results show that the change of the Ouke Fogu wetlands in the recent 30 years is about 2450 ~ 11400km ~ 2.