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1 坝地生产与水保效益陕北黄土丘陵沟壑区面积 44 5 83.4km2 ,占陕北总面积 5 5 .3% ,现有人口 340万人 ,有农耕地 79.3万 hm2 ,人均 0 .2 33hm2。本区有淤地坝 3.1万座 ,已淤地 4.2 1万 hm2 ,人均0 .0 1 2 6 hm2 ,占农田 5 .3%。1 996年坝地利用面积 3.5 8万 hm2 ,平均产量 3
1 Production of dam and benefit of water and soil conservation Benefit The area of loess hilly and gully area in northern Shaanxi is 44 5 83.4km2, accounting for 53.3% of the total area in northern Shaanxi. The existing population is 3.4 million with 793,000 hm2 of agricultural land and 0.23hm2 . There are 31,000 siltation dams in this area, with 4.2 million ha of silting land and 0. 0126 ha of per capita, accounting for 5.3% of the farmland. In 1996, the dam land use area was 3.58 million hm2, with an average output of 3