Classification And Evaluation Of Site Types In Hilly Areas Of Daqing River Basin

The study takes the hilly area of the Daqing river basin as the research object,and uses a combination of field investigation and laboratory test analysis to analyze the site factors.Based on multivariate statistical principles such as correlation analysis,principal component analysis and cluster analysis,qualitative and quantitative analysis are combined to select the dominant factors and divide the site type of the hilly area of the Daqing river basin.Comprehensively consider the topography,soil factors and other site factors in the study area,and evaluate the site quality through the combination of mean square error decision analysis and analytic hierarchy process;and on the basis of the site type division and site quality evaluation in the hilly area of the Daqing river basin,the suitable planting species of different site types were studied in the small watershed of the Daqing river basin.Thus,the scientific basis of "suitable land and suitable trees" and "efficient forest planting" can be provided for the construction of water source forest in the hilly area of the Daqing river basin.The research conclusions are as follows:(1)Through qualitative and quantitative analysis of site factors,and screening site factors,the dominant site factors were selected as altitude,slope,aspect and soil type.On this basis,28 site types were divided from 90 typical sample plots.Hill type site type group: hilly flat brown soil site type,hilly slope shade brown soil site type,hilly gentle slope slope brown soil site type,hilly slope sun slope brown soil site type,hilly gentle sun slope brown soil site type,hilly slope Site type of shady coarse-grained soil,type of hilly steep shady-coarse soil,type of hilly steep-yang-slope coarse-grained soil,type of hilly gentle-yangslope coarse-grained soil;type of low-mountain site: low-mountain steep-yang-slope brown Types of loamy soils,types of low-lying slopes of brown soils,types of low-lying slopes of brown soils,types of low-lying slopes of brown soils,types of low-lying slopes of brown soils,types of low-hills steep slopes of brown soils,low-mountain flatslopes Type,site type of low-lying slope slope stony soil,type of lowlying slope slope stony soil,type of low-rise slope slope brown soil,type of low-rise slope slope brown soil,type of low-hill slope slope brown soil Site type,low mountain steep shady soil site type,low mountain steep steep brown soil site type,low mountain flat land brown soil site type;Zhongshan mountain site type group: Zhongshan gentle sun slope brown soil site type,Zhongshan Pingyin Sloping brown soil Type,Zhongshan slow shady site type brown soil,brown soil Zhongshan oblique shady site type,Zhongshan anxious brown soil steep shady site type.(2)The overall site quality of the hilly area in the Daqing river basin is poor,and there is no "excellent" site in the typical land samples investigated and analyzed;The proportion of the site type with "good" grade is 21.43%,the proportion of the site type with "medium" grade is 71.42%,and the proportion of the site type with "poor" grade is 7.15%.(3)Taking the Dalan small watershed as the research object,11 suitable trees,10 suitable shrubs and 41 suitable herbs were proposed for its 15 site types;and the combination of arbor and grass and shrub and grass according to the site quality grade And herbal restoration measures.