河龙区间南片的淤地坝及其在经济建设中的地位和作用

在黄土高原丘壑区打坝淤地已成为一项行之有效的水土保持治沟工程措施，具有防洪减灾、固沟拦泥、减少入黄泥沙、调整土地利用结构、增田增产、改善生态环境等多重效益。截止１９８９年底，该区已建成淤地坝１１０８３座，已淤实有累计坝地面积１．０９６万ｈｍ２。１９５６～１９８９年３４年间，淤地坝累计减洪量８．２５６亿ｍ３，减少入黄泥沙７．１３４亿ｔ。

DAMS TO THE SOUTH OF HEKOU-LONGMEN SECTION OF YELLOW RIVER AND THEIR FUNCTIONS

In the hilly areas on the Loess Plateau,building dams is a effective measure for harnessing gullies.They function as preventing flood and reducing damages,checking sediments,reclaiming land ,raising yield,improving environment and so on.Up to 1989,this region has 11083 dams,the damed farm lands are 10960hm 2.In the 34 years from 1956 to 1989,the dams have reduced flood water 8256 million m 3,checked sediments 7134 million tons for the Yellow River.