| Agroforetry was defined formally as a special branch of biology science since 1980s after International Committee Research Agro-Forestry (ICRAF) have been founded. From then on, many researchers have studied the advantages and developing potentials of agroforestry management. Now agroforestry management and contour hedgerows technology has been a new measure applied in restoring degenerating vegetation on sloping cultivated land all over the v.orld. This technology may significantly hold back runoff, prevent soil and water loss and combine agriculture with forestry to form a rational ecosystem. Through this technology we may achieve high economic, biological and social benefits. However, this technology was greatly influenced by environmental factors such as soil and climatic conditions while popularizing. Therefore, we should select suitable plant species and establish rational structure and draw up appropriate regulations according to different environmental conditions.In order to find otit a new set of measures to control soil erosion on sloping cultivated farmland in Three Gorges Reservoir Area, we have adopted narrow terrace and put agroforetryjmd contour hedgerows into effect by means of sustainable development theories, ecological theories, and social economic theories since Feb. 2001. On the basis of field investigation and located observations, the laboratory experiment and the mathematical analyzing, we have systematically studied the model and technology of agroforestry which were adapted to Three Gorges Reservoir Area. Besides this, the effects of agroforestry on controlling soil and water loss, ameliorating soil property were evaluated quantitatively, aswell. These results are shown as below:(1) Through investigating local agroforestry model in Three Gorges Reservoir Area, we may conclude that agroforestry management is an effective way that brings soil resources utilization from single planting and extensive farming to comprehensive and intensiveone.(2) The main models of agroforestry in Three Gorges Area include courtyard composition, contour hedgerows, Chinese fir-rhizome composition, fruit-crop intercropping, and so on.(3) The key link in establishing agroforestry is to select fine plant species in accordance with local natural condition. To make full use of the coexistence and to avoid rejection between different species is very important in obtaining the utmost benefits.(4) Agroforestry systems with rational structure could conserve soil and water, ameliorate soil property, raise land use efficiency and increase the system productivity and achieve significant ecological, social and economic benefits.(5) Data from 10-year statistics showed that: Rainfall in this region is plentiful but the distribution in different month and different year is unequal. The three maximum months are June, July and August, which account for 18.72%, 18.49% and 17.17% of annual rainfall respectively. Rainfall from June to August accounts for 50% of the annual. Rainfall from December to February only accounts for 5.53%. In raining season, rainfall could account for more than 70% of annual. Precipitating process in this area could be divided into four types, namely: even type, gradually decreasing type, eruptive type and peak type. At the same time, the different raining type produced different sediment-transporting process.(6) In agroforestry and contour hedgerow treatments, soil structure and soil texture is improved with soil bulk density decreasing and soil porosity and capillary pore increasing. Finally, water-holding capacity is improved.(7) Soil loss in small plots of comprehensive management treatments is significantly lower than that in control. This result proved that agroforstry management and contour hedgerows could conserve soil and water efficiently.(8) As a whole, soil water content in these treatments which implementing agroforestry and contour hedgerows are more than that in the control. But, in August, the situation run counter to the other months...
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