Study On Climatic Adaptablity Division About Main Tree Species Of Dry Fruit Of Economic Forest In Gansu Province

On the basis of investigating resources of economic forest, the study using the different of distribution area and the restriction as principle, apply the method of comparison and analysis to compare and analyze the leading factors of where every tree species distributes, its biological character istle and ecological distribution habits. Establishes evaluation inclinator system according to climatic adaptability, gives value to climatic condition of 87 counties in Gansu province, appraises climatic adaptability area and second-rate climatic adaptability area of Juglans regia, Castanea mollissima, Zizyphus jujuba and Prunus armeniaca according to the different range of the value.The results show that: (1) Juglans regia relatively distributes in larger area in Gansu. The climatic adaptability area includes mountainous region, hills land and gully land, where economic forest growing, in Longnan district, loess plateau area in Longdong district (besides Huan county and Huachi county ) . Second-rate climatic adaptability area includes Lanzhou and Baiyin city, Jingtai county, Jingchuang, zhouqv, Huachi, Gangu, Wenxian and Wudu county, part of Hexi corridors; Gannan and Linxia state and most area of Dingxi district belong to climatically inadaptable area.(2) Climatic adaptability area of Castanea mollissima is small. Castanea mollissima grows well only in the soil with pH6.6-7.5, and solely distributes in mountainous region and river valley in the south of Longnan district TianshuK Beidao and Gangu country , because most of soil in Gansu province with pH 7.5. The middle part of Gansu province, Longdong and Dingxi district, Gannan and Linxia state and Hexi corridor belong to climatically inadaptable area. So Gansu province shouldn't advocate to texpand production of Castanea mollissima.(3) Zizyphus Jujuba has large distributions area and high yield, which shows that Gansu province has great production and potential capability, and that it can be managed as heading product.Zizyphus Jujuba climatic adaptability includes theLoess plateau area in Longdong, Tianshui city (besides Zhangjiachuan county ) and Li county in mountainous region of Longnan district, irrigated area in the middle of Gansu province and irrigated area oasis in the middle part of Hexi corridor; Second-rate climatic adaptability area includes Longnan district(besides Li county), Anxi county, Yumen, Jiuquan,Yongchang in Hixi corridor and Longxi county . Other areas of Gansu belong to climatically inadaptable area.(4) The development ofPrunus armeniaca is in initial stage.If s climatically adaptable area includes Loess plateau area in Longdong, Gangu county, Wushan county, Qingshui county and the middle part of Yellow River irrigated area; Longnan district, Tianshui city, Qingan county and part of irrigated area in Hixi corridor are second-rate climatic adaptability. Other areas belong to climatically inadaptable area.