| South China karst area is one of the main ecologicalenvironment fragile zones in our country, where soil and water lossis a serious problem. Large areas of rocky desertification in karstarea south reflected the seriousness of the soil and water loss.Scholars found that in south China karst, soil erosion modulus inthe region is small, but has led to serious rocky desertificationduring this study area. Therefore, the carrying out of karst waterand soil conservation work has a great urgency. There are55rockydesertification comprehensive treatment pioneers in Guizhouprovince, but it is100in all the contury. The research of benefitmonitoring and evaluation about soil and water conservation is soimportant that it can represent the entire karst areas. We choosetwo small watersheds as our research areas. They are Chaoying smallwatershed of Salaxi in bijie and Dingtan small watershed of Huajiangin Zhenfen-Guanling. We collect the data through field sampling andmonitoring on April August and December three times every year. Weanalyze the data combined with social and economic survey by SPSSand EXCEL. We try to formulate a method and index system, which ismonitoring and evaluating the benefits of soil and waterconservation in karst rocky desertification control, and we monitor and evaluate the benefits.(1)Overall, effect of soil and water conservation is obvious.The soil degradation index of rocky desertification both inChaoyingwatershed and Dingtan watershed has declined, which can beproved through the reducing of soil erosion modulus, theameliorating of soil pore structure, the enhancing of resistanceto corrosion and capacity of moisture retention, the increasing ofnutrient element content. But the change of soil erosion moduluswas tortuous, which showed that the picking up of2009and2012.This was result of a long time natural drought and damage tofragileenvironment. It has carried out a series projects and reseaechesaccording to different rocky desertification management in Dingtansmall watershed during the period of nith five-year and tenthfive-year. The rocky desertification of Dingtan small watershed inHuajiang was mainly medium and intensity. Although the rockydesertification area has declined, the soil and water loss was stillserious during the rainly season. The work of management and monitorwas started at2011in Chaoying small watershed of Salaxi. Thebenefit was not obvious because the short time. The work ofmanagement and monitor was also remained to be future strengthened.(2)There is large gap between soil and water conservationbenefits in different grade rocky desertification. The intensity of rocky desertification soil and water conservation benefit is notvery clear or almost none. The benefit of soil and waterconservation is gradually appearing after the project of soil andwater conservation in moderate and slight rocky desertificationareas. The benefit of soil and water conservation is relativelyobvious in micro degrees and rocky desertification areas. Soilphysical and chemical properties of different grade rockydesertification had made an evident improvement, especially in thetwo measures of natural water content and soil field capacity.All the grades of rocky desertification were better than before.The contents of nutrient elements were evident improvement inalmost all sample areas except potential rocky desertification.Because the soil physical and chemical properties of Dingtan smallwatershed have been optimized, the corrosion resistance of the soilhas improved, and it also played an important role in water and soilconservation. There was potential rocky desertification that whichhad more soil animal number of individuals and groups. Althoughthese indicators data had feedback on benefits of soil and waterconservation in the study area to a certain extent, these innerlinks between indicators and soil and water conservation benefitswere worthy of further research, and also the weight of erery indexin the whole evaluation index system. Soil and water conservation benefit was obvious in potential rocky desertification in Dingtansmall watershed, but it was in moderate and mild rockydesertification in Chaoying small watershed.(3)There was a significant gap between soil and waterconservation benefits under different land use ways. This kind ofdifference based on different grade rocky desertification wascaused by the different soil and water conservation measures. Thebenefit of soil and water conservation in dry land was the mostsignificantly contrast before and after the soil and waterconservation project. In recent five years, dry land, ruralresidential areas, industrial and mining land increase, while thepaddy field, shrub land gradually reduced in Dingtan smallwatershed. This change in the ways of land use puts the challengeon soil and water conservation work. It has large growth of economicforest land, grassland, land for residential areas and mining also,but the dry land, shrub land has decreased in nearly two years. Thischange in the ways of land use played a great facilitation for themonitoring and evaluation work on benefits of soil and waterconservation. It has enlarged the area of economic forest, grass,Chinese herbal medicine planting in the study area, and reduced thearea of dry land. In order to improve the ecological environmentgovernance mode and technolocgy, there would be a lot we can do to avoid the discount in concrete implementation phase. It wasresulted that the resident’s confidence of the desertificationcontrol in the study area has shaked. Therefore, karst rockydesertification comprehensive treatment is not only to achievegovernance rocky desertification, water retention, and improve theecological environment, but also to make local residentsparticipation, and benefit, finally achieve the ecological andeconomic benefits of the double harvests. |
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