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机构地区:[1]兰州大学地理系 [2]甘肃省环境保护研究所
出 处:《干旱区地理》1991年第2期76-81,共6页Arid Land Geography
基 金:国家自然科学基金"西北干旱区自然环境及其合理利用"资助研究课题
摘 要:石羊河流域不同地段的自然生态环境、具有不同的农林牧生态适宜性。本文以流域为基本单元,根据流域农业生态经济区划的原则,将石羊河流域划分为3个生态经济区、9个亚区和20个小区。Shiyang river basins, One of the major three inland basin in Hexi desert area, is a typi-cal and independent physical geographic unit.The river comes from the eastern sector ofQilian Mts and flows northward into sand desert, and is about 300km long and 41149km^2ba-sin areas. The Oasis are developed in the mid-reaches of the corrider plain and lower reachesof the alluvial-lacustrine zone, and the annual precipitation respectively is 100-200mm and50-100mm.The Agro-Ecological environment has clear rule of regional differentiation onmidium scale and different suitabilities. Based on the regionalization preciple, the paper hevedivided the basin into three ecological-economic regions whose boundary line is about ac-cording to upper, mid, lower.reaches of the river basim, 9 subregions and20minor-regions, the result as follows: 1. Forestry, animal husbandary ecological-economic region in the upper-reaches ofriver in QiLian Mts including 2 sub-regions and 4minor-regions. 2. Irrigating agriculture regions in mid-reaches of river in corridor plain including 4Sub-regions, 9 minor regions. 3. The region conserving economics in the lower reaches of river in BeishanMts-Alashen Pleateau, including 3subregions, 7minor-regions.
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