spontaneous factor meaning in English

自发因素

Took sha - zhuyu and east shore of qing - hai lake as the examples and based on the mass of field survey and soil analyse , took comparative method , we carried through the researches on the causes of the desertification , the origin of sandy desertificational land substance , the development diversification and difference of soil characteristic in process of manual and spontaneous vegetation recovery in high frigid regions and make out the taxonomy of desertificational land in high frigid region of china . the result obtained are summarized as follows : 1 . the development of the desertificational land in high frigid regions is caused by the manual and spontaneous factors
论文首次对高寒地区的砂质荒漠化土壤进行系统研究，以沙珠玉和青海湖东岸为例，通过野外考察和土壤样品室内化验，采用对比分析的研究方法，对中国高寒地区荒漠化的成因和研究区砂质荒漠化土地的形成演变，土壤发生特性、人工植被恢复和自然植被恢复过程中土壤的发育差异和性质变化进行系统研究，并用系统分类体系对研究区土壤进行类型划分，得到主要结论如下： 1 、高寒地区荒漠化的发生发展是在自然因素和人为因素共同作用下进行的，沙珠玉地区风沙土是就地产生的，青海湖东岸地区风沙土主要是由风从湖的西岸搬运而来的，两地区砂质荒漠化发展仍然十分严重。