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[[Image:perm rock dam icon.png|right|80px]]
[[Image:PermeableRockDam2.JPG|thumb|right|200px|堆石透水坝Permeable rock dams, 流水flowing. Photo: [http://il.water.usgs.gov/asian_carp/images/IM_Canal/3-Illinois%20and%20Michigan%20Canal%20Flow%20Barrier_recent.JPG USGS.]]]
__NOTOC__ <small-title />
堆石透水坝Permeable rock dams provide a more effective and popular technique for controlling gully erosion than gabions. Permeable rock dams, in addition to the effective control of gullies, have resulted in considerable crop yield increases behind the dams. Gullies are rehabilitated by the deposition of silt behind the dams, increasing the depth and quality of the soil immediately behind the dam as a result of the deposition of fertile silt. They have also improved the amount of moisture available for crops. Yields of sorghum from land restored with permeable rock dams range up to 1.9 t/ha compared with a yield of 1 t/ha from equivalent, untreated land. Other crops planted behind permeable rock dams include rice (on heavy soils), pearl millet and peanuts.