a case study in Xingguo county 其他题名：a case study in Xingguo county a case study of Songxian county a case study of Qingdao City a case study of Jiangsu Province a case study of Qinghai Province 土地利用生态安全调控研究：以兴国县为例：a case study in Xingguo county a case study of Xinjiang a case study of Guizhou tobacco industry a case study of Yunnan Province