Study On The Ecoclean Small Watersheds Construction Theory And Practice

Based on massive investigation and study, the concept, classification principles, index system of the three defense areas of ecoclean small watersheds as well as the management measures system of water and soil erosion were thoroughly studied by qualitative and quantificational integrated means.1) According to the overall requests of "water resource protection, environmental improvement, disaster prevention and cure, development promotion", focused on water resource protection, the small watersheds were divided into three defense areas: ecological restoration area, ecological control area and ecological protection area.The first defense area, the ecological restoration area, is located in the far mountain and exiguously populated area, where the mountain is higher and steep slope, soil layer are thin and superficial, so it is easy to cause serious soil erosion when meeting with rainstorm, moreover, the natural disasters occur ever and agah such as debris flows and landslide.The second defense area, the ecological management area, is located in the agricultural plant areas in piedmont, or at the foot of the mountain, and the frequent human activities areas, where the ecological environment is frail, soil erosion is serious, which is the main origin of the silt; Simultaneously there have many villages and small towns with concentrated tourism, which is the main place of non-point source pollution because of a great deal of wastewater discharge , garbage accumulation as well as fertilizer and pesticide application in farmland and garden plot. In addition, water and soil loss caused by human activity are serious such as exploitation and construction activity.The third defense area, the ecological protection area, is located in the two sides of the river (ditch) and around the lake storehouse, which is the main area of sand digging...