| To get a handle on the implementation effect of the state key project of soil and water conservation in the area of Huaihe River Valley and define the mainly existing soil erosion problems of key project, this research covers representative region of key project in the area of Huaihe River Valley. By combining sensing investigation and ground surveys methods, we conduct a comprehensive analysis and explore by combining space and all the concrete measure. We aim to provide reference, theory and technical basis for the planning,management and benefit evaluation of future state key project of soil and water conservation in the area of Huaihe River Valley.1.The improvement of soil and water conservation in area of the key project(1) The area of soil erosion and the erosion modulus in area of the key project are reduced. By 2013, the area of Dayu watershed interpretation region declined by 19.2%,the erosion modulus declined by 34.7%. The area of Taoling reservoir watershed interpretation region declined by 74.7%,the erosion modulus declined by 60.6%.By 2014, the area of He erchong watershed interpretation region declined by 61.0%,the erosion modulus declined by71.2%.(2) The physical and hydrology properties of soils in engineering of changing mountain slop into terrace field regionThe physical and hydrology properties of soils in terrace region has improved to some extend. Among them, the fractal features of soil particle and porosity infiltration rate of soil in terraced fields has improved a lot, especially porosity infiltration rate of soil.(3) The physical and hydrology properties of fields under different tillage measureThe crop terraces cultivated by ridge and furrow and the forest-fruit terraces that no-tillage have both apparently improved the physical and hydrology properties. These characters of no-tillage way increased more than the former. The physical and hydrology properties of broken crop terraces cultivated by ridge and furrow has decreased apparently.(4) The amount of lost soil and nutrients in region of terrace projectThe amount of soil and lost nutrients in region of terrace project decreases. Comparing with the slope land, the amount of lost soil of the crop terraces cultivated by ridge and furrow and the forest-fruit terraces that no-tillage has been controlled by 77.9% and 92.9%. Theamount of lost soil of the crop terraces cultivated by ridge and furrow and the forest-fruit terraces that no-tillage has been equally controlled by 77.9% and 92.9%.(5) The soil and hydrology properties of enclosure regionThe enclosure project has improved the soil and hydrology properties of enclosure relict sparse forest and replanting sparse forest differently.Among them, the infiltration property and permeability of pore space are more improved. Besides, the improvement rate of the physical and hydrology index replanting silviculture is ten points more than enclosure relict sparse forest.(6)The coupling effect of terrace ecological economyIn regard to the economic output(Eo), when peanut is planted on terraces cultivated by ridge and furrow, the value is 60% higher than slope land; The Eo of terrace cultivated as bank is 13% lower than terraces cultivated by ridge and furrow. In regard to the ecological economic coordination index, when peanut is planted on terraces cultivated by ridge and furrow, the value is 81% lower than slope land; The Ec of terrace fruit trees(apple) cultivated is 13% lower than terraces cultivated by ridge and furrow(peanut).2. Soil erosion characteristic in area of key projectThe soil erosion pattern and form of project region mainly covers: slope erosion; gully erosion; road erosion; the collapse.The main harm of soil erosion of project region covers: losing water and fertilizer, soil degradation, declining of land productivity; water engineering conservancy Sediment loss,Guarantee of agricultural water or flood prevention function losses; drainage basin channel systems damages; transportation of production and living damages; chemical erosion damages and physico-chemistry functions, land productivity declines; forest land erosion leads to the declines of biomass, loss of vegetation structure function; gravity and torrential erosion ruin soil conservation project, endanger the safety of people.3.The problem of soil and water erosion and ways to prevent the soil and water erosion in the study areaThe problem of water and nutrient running off still exists in stone dike terrace. Gravity erosion(collapse, landslides) is serious in ridge terrace; Slope surface erosion is obvious; The secondary development of terrace slope caused soil and water erosion. It can build a high standard level terraced to establish engineering system for soil and water conservation of farmland.The problem existing in drainage system results in the decrease of terrace function to soil and water conservation, the water and nutrient run off seriously in cropland, latterly inducinggravel phenomenon; the slope or field flowing result in rill erosion. It can build high quality slope trench to perfect engineering system for the runoff discharge and utilization.The road have been eroded seriously because of lack of hardening or drainage engineering; Lack of drain-pipe protection of drainage ditch induce the deposition and damage of functional facilities; Road project short of governance cause soil and water erosion.It can construct high standard road to improve runoff drainage and storage of traffic and product engineering system.Siltation of channel small reservoir water engineering lead to the decrease of drainage and storage function. The standard of small watershed channel check dam facilities is low and the held effect of it is poor. It can build a multi-level channel check dam and weir dam to improve runoff held engineering system.It is unitary about tree species of soil and water conservation for afforestation in most of the regional slope. It can select the tree and shrub species mixed to build diversity of vegetation protection engineering system.It is not reasonable of economic forest measure configuration. It can implement soil and water conservation tillage management in woodland to form characteristic horticulture engineering system. |
