Widespread soil erosion and desertification have been caused by over cultivation and over grazing of the steppe and the steep slopes forced by population pressure in the region.

  • 数十年来对于水、土和生物资源的过度开发,是造成黄土高原及其毗邻荒漠草原地区广泛的沙漠化、土壤侵蚀、河水断流、湖泊干涸的直接原因。
目录 查词历史