| On the basis of the previous studies and through application of techniques of ecology and geographic information system expertise, this article investigated and monitored eight kinds of restoration and management models in the demonstration karst area of Chongqing Nanchuan District. Through the comprehensive statistical analysis, our aims were:1) to show the changes in ecological environment after the comprehensive implementation of ecological measures,2) to master the extent and effect of ecological restoration and measures of improving soil and controlling soil erosion,3) to evaluate its ecological and economic benefits,4) to select the optimal vegetation recovery mode,5) to provide guidance for restoration of the soil and water conversation in this area.The main research contents include the following aspects:(1) According to the different ecological restoration measures in this area, we selected eight typical recovery models, ecologically monitored each sample in time series, such as vegetation, soil, soil retention, runoff and erosion, regional climate.(2)We comparatively studied the ecological structure and function of vegetation in different restoration models. Through the investigation of vegetation in different restoration models, we use the population structure and quantitative characteristics to reflect changes in ecosystem structure; and use the changes of regional climate and soil properties to reflect the changes of ecological function.(3) According to the local conditions and the complexity of karst areas, we draft the eco-efficiency assessment indicators and criteria, establish a set of eco-efficiency assessment method and system, with an aim to provide a practical evaluation model for ecological benefit assessment of local environmental governance.(4) We evaluated the comprehensive benefit of all restoration models, and then selected the optimal recovery and management model, guide the process of rocky desertification control.The results show that:the most important conditions there, including the difference of the soil depth cause some degree of differences among community height, the average diameter, the average crown and the vegetation coverage of four kinds of artificial forests which were planted in 2002. Cinnamomum camphora (Linn.) Presl had the biggest vegetation coverage. In temporal patterns, except the traditional agricultural land, the vegetation coverage of all other recovery models increased gradually. Among all these models, Lonicera japonica Thunb had the fastest growth rate of vegetation coverage. In the study area, the recovery models which had the same ecological configuration mode, had similar species diversity index, species evenness index and dominance index. Respectively, abandoned land had the highest species diversity index, the next is the economic fruit planting patterns (peach and pepper), however, the artificial forest models had lower species diversity index. As for the dominance index, expect the abandoned land was low(0.2346), all the other artificial recovery models were very high. The changes of species evenness index between all the models were similar to that of the dominance index.The soil moisture of different recovery models had significant difference. The abandoned land had relatively high soil moisture, higher than most artificial models. In all standard plots, soil bulk density of upper layer (0-15cm) distinctly lower then that of lower layer (15-30cm), which the farmland had the largest difference between its upper layer and lower layer. Through analysis of variance, as for the upper layer soil bulk density, all the models were significantly higher than the traditional agricultural land. The order of soil bulk density from low to high was the traditional farm land, peach, abandoned land, pepper, Campher, Kashiwagi, Alfalfa and Honeysuckle. Under the same kind of recovery model, the non-capillary water holding capacity and soil water storage capacity from the surface soil to lower layer soil decreased gradually due to the increasing of soil bulky density. However, between the different recovery models, the improvement of soil water holding capacity were different. The order of soil water holding capacity and non-capillary water holding capacity from high to low was Campher, Kashiwagi, peach, pepper, Alfalfa, Honeysuckle, the traditional farm land and abandoned land. Under the same recovery model, the data of soil bulky density showed that rainy season>dry season; the data of soil porosity showed that rainy season> dry season; and the data of soil water holding capacity showed that rainy season0cm,0-15cm,15-30cm showed an increase rapidly, and then a slow down. The average soil temperature of all the other recovery models was lower than that of the control point. With the increasing of soil depth, soil temperature of all models decreased, and the gap of temperature between control point and other models reduced gradually. Relative humidity of all the models had the same change trend, and all displayed the curve closed to "V" shaped, which was opposite to the change of PAR and air temperature.The order of soil infiltration rate of all recovery models was:pepper> farm land> Campher> peach> Kashiwagi> Honeysuckle> abandoned land> Alfalfa. After the implementation of these restoration and recovery measures, the surface runoff reduced significantly in an average reduction of 36.37%-69.09%. Campher had the smallest surface runoff, and the control point-abandoned land had the largest surface runoff. The range of runoff coefficient was between 0.17 and 0.55, average was 0.299, which compared to traditional farm land reduced 81%. Compared with the traditional farm, soil erosion modulus of all recovery models decreased substantially. The abandoned land had the lowest soil erosion modulus, which was 85.8 t.km-2.a-1. Compared with the traditional farm, the soil erosion modulus in peach and pepper reduced 91.12%.Though grey relational analysis, evaluated the ecological and economic benefits of all the recovery models, the results showed that:as for the comprehensive benefits, which contended the ecological and economic benefits, Alfalfa, Kashiwagi, and abandoned land, these models were the optimal models while the worst model was the traditional farm land; On the case of focusing on economic, the evaluation score of Honeysuckle planting model improved particularly. This shows: the traditional farm planting model can not satisfy the requirements of ecological services. Rocky desertification areas should adjust the plant structure, and enhance the ecological protection capacity of agricultural ecosystem.
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