Study On The Characteristics And Prevention And Cure Techniques Of Stony Desertification In Xichuan County Of The Middle Line Of Water Diversion From The South To The North

The ecological benefits,economic benefits and social benefits of the Middle Route Project of the South-to-North Water Diversion Project are huge.Both the head of the Canal and the reservoir area of ??the Danjiangkou Reservoir in Henan Province are in the Xichuan County;the ecological resources and environmental problems caused by the desertification of the Rocky County are serious and have typical representation in non-karst regions.Xichuan County as the object,to carry out the mid-line of South-to-North Water Diversion District Xichuan County,the characteristics of rocky desertification and prevention and control technology,has important engineering theory and practical significance.The use of geography,geomorphology,landscape ecology,soil and water conservation and other disciplines theory,based on 3S technology,using on-site comprehensive survey and human-computer interaction interpretation,system analysis and other methods,the use of multi-band high-resolution remote sensing images and related data The results of the map and ARCGIS,ENVI,FRAGSTATS FOR ARCVIEW and other software,through the calculation and analysis of the spatial distribution characteristics of rock desertification in Xichuan County,landscape pattern characteristics,prevention and control mode and prevention and control technology,the conclusions are as follows:(1)The total land area of Xichuan County is 2819.8045km2,of which the rock desertification area is 745.5393km2,accounting for 26.44% of the total area of the area.The area of heavy,medium,light and potential rocky desertification is 54.7506km2,80.5671km2,228.2166 km2,382.005km2,respectively accounting for 1.94 percent,2.86%,8.09%,13.55%of the total land area of Xichuan County.(2)According to spatial characteristics such as lithology,map slope,aspect,average elevation,etc.,the desertification in Xichuan County mainly occurs at elevations of200~500m,carbonate rocks,S~SW slopes,and slopes of 8 o ~.25o area range.The distribution areas of rock desertification in the carbonate group,clastic rock group,multi-layered soil body,metamorphic rock group,and intrusive rock group are respectively461.59 km2,164.54 km2,119.2 km2,66.86 km2,and 40.63 km2.The incidence rates were58.26%,23.56%,1.96%,30.74%,24.98%,respectively;Severe,moderate,mild,and potential levels of rocky desertification were higher in the carbonate group than in the clastic rock group.The metamorphic rock group,intrusive rock group,and multi-layered soil lithology area reached 54.60%~71.03%,17.95%~23.91%,4.79%~12.26%,2.17%~7.98%,and1.25%~2.90%,respectively.The rocky desertification plot has a slope of 15o~25o with a maximum of 322.767km2,accounting for 43.29%,a >35o area with a minimum of 2.6793km2,and only accounts for0.36% of the stone,8o~25o with a total area of ??588.0015km2,accounting for 78.87%;the rocky desertification land slope is Area less than 25o increases with slope increasing area.When slope is more than 25o,area decreases with slope increasing.When slope is over 35o,the area is very small.The desertification of stone is mainly distributed in the area of ??S slope,which is229.3893km2,accounting for 30.77%,the slope area of ??SE and SW is 311.4495km2,accounting for 40.66%,the slope area of ??E,W,NE,NW,N is 213.0066km2,accounting for 28.57%;The area along the slope is the smallest,only 13.95500 km2,accounting for only1.87%.The distribution of stony desertification increases from clockwise to slope-to-slope,and reaches the maximum when slope S arrives,and continues along the slope.The hourly conversion distribution area showed a downward trend.The area of ??rock desertification ranged from low to high in the order of potential,mild,moderate and severe.The stony desertification is mainly distributed on the elevation belt of 200~500m,with an area of ??554.7981 km2 and accounting for 74.38%.The area with an elevation above the elevation of 200 m is 57.9051 km2 and takes up 7.76%.The area above the altitude of 500 m is133.1361 km2 and takes up 17.86%.The area with the smallest elevation of 700-800 m was only 13.8582 km2,accounting for only 1.86%.The area of ??stony desertification increased with the elevation above sea level and reached the maximum at 200-500 m above sea level.After that,While the area is increased.When the elevation is 700 ~ 800 m,the area of??stony desert land is the smallest.When the altitude is higher than 800 m,the area increases slightly.(3)According to the analysis,the landscape of rocky desertification in carbonate sub-region is obviously more urgent than the most fragmented,and the needs of treatment and restoration are more urgent.The clastic rock sub-region,metamorphic rock sub-region,intrusive rock sub-region and multi-Less,the relative density of patches is small,and it is less difficult to compare the recovery of ecological governance with carbonate rocks.Stony desertification is unevenly distributed.Non-potential and mildly stony desertification is the dominant landscape type,affecting the overall landscape more than moderately severe rocky desertification.Moderate and severe stony desertification has a small area of ??single plaque and severe stony desertification with sporadic scattered and fragmented state.The study divides the landscape pattern of stony desertification into concentrated distribution of heavy rocky desertification patches,Moderately distributed rocky desertification,non-rocky desertification with potential rocky desertification,mixed distribution of potential rocky desertification with severe rocky desertification and non-rocky desertification,and several types of rocky desertification interphase distribution 5 types.(4)Divide five types of landscape pattern from the landscape scale,and divide the landscape pattern from slope to channel,valley and area.Through research,the prevention and control countermeasures for severely distributed desertified rocky desertification areas are to vigorously carry out mountain closure and afforestation and artificial auxiliary ecological restoration technologies to increase the coverage of vegetation;the prevention and control countermeasures for the protection of mildly moderately litho graben desertification accumulation areas are to protect and develop water and soil.Resources,strengthen soil and water conservation,adjust agricultural production structure;control measures for potential and non-lithic desertification-based distribution areas to prevent continued destruction of potential rocky desertification,non-rocky desertification matrix,and control the expansion and reduction of bare rock patches It is a possibility of becoming a landscape base;the prevention and control measures for mixed distribution areas of severe and potential and non-lithic desertification are mainly to treat heavy stone desertification,and potential rocky desertification areas are laid out according to local conditions,and non-lithic desertified landis rationally used and protected.Several prevention and cure measures of phase distribution areas of stony desertification type are rational utilization,comprehensive development and comprehensive protection.Based on the characteristics and application examples of different desertification regions,through research and analysis of applicable conditions,mode allocation,selection of species and types of trees and grasslands,it is concluded that the main types of prevention and control measures for desertification include the restoration of vegetation for closing hillsides and afforestation,ecologically efficient fast-growing forests and shrubs,and comprehensive utilization type forests.Grass three-dimensional optimization,mountain ecological agriculture,soil and water conservation comprehensive management of five kinds of patterns;on this basis,study elaborated the closure of natural forest protection(forest protection),closing hillsides afforestation(grass),artificial afforestation Forest control technology,ecological agriculture and other biological control technologies and engineering prevention and control technologies for stone fish scale pits,Shigufang,land consolidation,etc.;key research has summarized the technology of large-acre soil preparation,stone block building and customer soil,blasting site preparation,and air pressure drilling bio-site preparation.Pit cover,pit cover film,pit cover rock,cover grass,water-retaining agent surface coverage,the application of water-retaining agent,water-saving technologies such as bio-water technology measures...