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出 处:《中国水土保持》2008年第2期24-27,共4页Soil and Water Conservation in China
摘 要:石羊河流域作为西北干旱区内陆河流域生态退化的典型,因其特殊的地理位置,成为我国北方沙尘暴的重要源地之一,影响到整个北方地区的天气状况。本研究在建立解译标志的基础上,对1999年和2004年两期卫片进行比较,并到现场进行重点核实,首次建立了石羊河流域荒漠化评价指标体系,结果表明石羊河流域荒漠化面积呈发展趋势,而且从程度上来说,向两极发展,即极重度、轻度面积增加,中度和重度面积减少,这与有关专家的预测和实际情况基本一致。Being as a typical example of ecological degeneration of endorheic drainage in the northwest arid region,Shiyang River basin becomes one of the key source areas of sandstorm of north China for its special geographical position,affecting the weather condition of the whole north China.Based on establishing symbol interpretation,it compares the satellite images of 1999 and 2004 and conducts on-the-spot key verification and firstly establishes evaluation index system of desertification of the river basin.The outcomes show that the desertification area of the river basin is in the trend of development and develops towards polarization to a certain degree,i.e.extremely serious-degree and light-degree areas are increased and medium and serious-degree areas reduced.The actual situation is of basically the same as that predicted by related experts.
分 类 号:X171[环境科学与工程—环境科学]
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