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干旱河谷地区一直是川西人类农业活动中心,各种农业耕作活动均发生在河谷地带。同时干旱河谷地带也是人类居住、城镇发展中心和交通要道等基础设施的集中区域。人类频繁活动和过渡利用往往加速植被退化,形成荒山荒坡,生态环境极为脆弱。夏季高温,紫外线辐射强烈,易发日灼,冬季寒冷低温,易发生冻害,降水量与蒸发量严重失调,蒸发量是降水量的3——5倍,水分严重亏损;土壤石砾含量高,肥力低,保水差;质地细腻透水性差,该区现有植被种类稀少,可供选择造林树种极少,这些不利因素,增加造林营林工作的难度,制约着该区区域造林成效和营林质量。本文在对阿坝州干旱河谷分布区域面积、气候、土壤及植被等基本情况及造林成效的充分调查分析基础上,发现了干旱河谷区植被恢复上存在的一些问题,并针对问题提出了一些可行性的对策。
The arid valley has always been the center of human activities in western Sichuan and various agricultural activities occur in the valley. At the same time, the arid valley is also a concentrated area for infrastructure such as human settlements, urban development centers and thoroughfares. Frequent human activities and transitional use often accelerate the degradation of vegetation, the formation of barren hills and slopes, the ecological environment is extremely fragile. High temperature in summer, strong UV radiation, prone to sunburn, the cold and cold in winter, prone to frost damage, precipitation and evaporation of a serious imbalance, the evaporation is 3 - 5 times the amount of precipitation, water loss; soil gravel content, Low fertility and poor water retention; fine texture and poor water permeability; scarce existing vegetation types in the area; few afforestation species available for selection; these unfavorable factors increase the difficulty of afforestation and forestation and restrict the afforestation effectiveness and quality of silviculture in this area . Based on a full investigation and analysis of the basic situation of the distribution area, climate, soil and vegetation, and afforestation effectiveness of the arid valley in Aba Prefecture, this paper found some problems in the restoration of vegetation in the arid valley area and put forward some feasible suggestions Countermeasures.