| 1. | Finally , this paper makes an appraise and policy recommendations to the great projects such as shift grain for forest and green project , shelter forest of three northern areas of china project , and beijing , tianjin sand source cure project , etc 最后本文对我国退化土地治理比较大的工程项目:退耕还林还草工程、三北防护林工程、和京、津风沙源治理工程等作出评价和政策建议。 |