求翻译：河流上游破坏植被使水土流失严重，河流下游河床泥沙淤积4.河流中游围湖造田，湖泊面积缩小，调蓄径流的能力降低。是什么意思？

Damage vegetation serious soil erosion in upper reaches of the River, River sedimentation of the river bed 4. empoldering middle reaches of rivers, Lakes area reduced, reduced regulation of runoff.

river Upstream vegetation make serious soil erosion and sedimentation downstream River Reclamation of land from a lake of Stream 4 rivers, lakes, diminishing the size of runoff water storage capacity.

Upstream the rivers destroys the vegetation to cause the soil erosion to be serious, the rivers downstream river bed silt silts up 4. rivers middle reaches to reclaim land by surrounding and filling in lake bottom, the lake reduction of area, stores and regulates the runoff ability to reduce.

Damage vegetation serious soil erosion in upper reaches of the River, River sedimentation of the river bed 4. empoldering middle reaches of rivers, Lakes area reduced, reduced regulation of runoff.

Damage vegetation serious soil erosion in upper reaches of the River, River sedimentation of the river bed 4. empoldering middle reaches of rivers, Lakes area reduced, reduced regulation of runoff.