Distribution Characters Of Fine Root In Several Different Forest Stands And Its Relation To Soil Environment In The Northern Slope Of Qinling Mountain

The root is the main organ of trees for nutrient and water absorption. In this study, fieldmeasurements analysis was conducted with several different forest stands in the northernslope of Qinling Mountain. Characters of fine root and soil physicochemical properties in theforest stands were studied and the effects of soil physicochemical properties on fine rootdistribution characteristics were illustrated. The results have a positive value for reveal rootdistribution characteristics and soil properties in the forest stands. This study could provide ascientific basis for dynamic estimate of the soil carbon and plantation construction in thenorthern slope of Qinling Mountain.This study has obtained the following results.1. The fine root biomass of Robinia pseudoacacia, Populus cathayana and5-year-oldpoplar plantation in the northern slope of Qinling Mountain decrease with the increase of soildepth. Fine root surface area and length density also decrease with the increase of soil depth.2. The studies on the relationship between the fine root biomass, surface area, lengthdensity and the effectiveness of soil resources showed that diameter is an important structuralfeature of root, and the roots of different diameter classes reflect different physiologicalfunctions. The biomass, surface area, and length density of roots≤2mm in diameter weresignificantly correlated with soil organic matter and available nitrogen, but no significantcorrelations were found for the roots2-5mm in diameter.3. The distribution characters of fine root in Robinia pseudoacacia, Populus cathayanaand5-year-old poplar plantation in the northern slope of Qinling Mountain were effected bythe complex of soil physical and chemical properties.4. The studies on the relationship between fine root distribution characteristics of5-year-old poplar plantation and soil properties showed that Soil bulk density is an importantfactor that affects the distribution of fine root in plantation. There was abundant precipitationin the Qinling Mountain which resulting in soil moisture of0-80cm was stable. Soil moisturedid not become the factor limiting the growth of fine root.5. The studies on fine root distribution characteristics of Robinia pseudoacacia in the northern slope of Qinling Mountain showed that, among the three kinds of fine rootparameters (fine root biomass, fine root surface area, fine root length density), fine rootsurface area has the most close relation with the nutrient acquisition.