Study On Distribution Of Soil Nutrient And Their Relationship With Growth Characteristics Of Pinus Sylvestris Var.Mongolica And Pinus Tabulaeformis Artificial Planations

By using Pinus sylvestris var.mongolica(P.sylvestris)and Pinus tabulaeformis(P.tabulaeformis)artificial plantations as the research objects in Liaoning province,Spatial distribution of soil nutrient and the growth traits of two tree species were studied.The aim of paper is to provide the maintenance of soil fertility and forest management of P.sylvestris and P.tabulaeformis constructive species and offer a theoretical guidance.In this paper,P.sylvestris and P.tabulaeforrmis tree species were investigated in western Liaoning(Jianping and Fuxin)and the eastern Liaoning(Huairen,Qingyuan and Benxi)regions,according to the different slope positions(upslope,midslope,low slope),slope direction(shady-slope,sunny-slope)and soil depth(0～15cm,15～30cm).Soil samples were collected accordingly.Soil nutrients like soil organic C,soil Ca,soil total N,soil total P,soil available N and soil available P;growth traits like the tree height,diameter at breast height,ratio of diameter at breast height to height and crown growth were investigated,the results of the study concluded as follows:(1)There are significant differences in soil nutrients between different slop positions,slope directions and soil depth of P.sylvestris and P.tabulaeformis plantations in western Liaoning.The variation trends of soil organic C,soil Ca,soil total N,soil total P,soil available N and soil available P in P.sylvestris and P.tabulaeformis plantations show that:low slope>midslope>upslope,shady slope>half shady slope>sunny slope>sunny slope).Meanwhile,soil nutrient contents in P.sylvestris and P.tabulaeformis in upper soil layer are higher than that of the lower soil layer.(2)There are significant difference between the different slop positions,slope directions and soil depth of P.sylvestris and P.tabulaeformis artificial plantations in eastern Liaoning.The variation trends of soil organic C,soil Ca,soil total N,soil total P,soil available N and soil available P show that low slope>midslope>upslope,shady slope>half shady slope>sunny slope>sunny slope.Meanwhile,soil nutrient contents in P.sylvestris and P.tabulaeformis in upper soil layer are higher than that of the lower soil layer.(3)The relationship between soil nutrients contents,soil nutrients and the growth traits of P.sylvestris and P.tabulaeforrmis artificial plantations under different slope positions,slope direction and soil depth in western Liaoning were analyzed.The correlation coefficients in low slope are higher than that of midslope and upslope.The correlation coefficients in shady-slope are higher than that of sunny slope.To sum up,soil nutrients in the P.tabulaeformis artificial plantations under low,shady slope has a significant positive related to soil organic C,soil total N,soil total P,soil available N and soil available P(p<0.05).Soil nutrients in P.tabulaeformis artificial plantations under low,shady slope had close relationships.And soil organic C,soil total N,soil total P,soil available N and soil available P are significantly positively related to diameter at DBH,tree height(p<0.05).The soil nutrients content in low,shady slope in P.sylvestris artificial plantation is higher than the midslope and upslope.The correlation coefficients of soil nutrients content under shady slope are higher than that in sunny slope.Soil nutrients in low,shady slope of P.sylvestris are significantly positively related to each other(p<0.05).(4)The relationship between soil nutrients contents,soil nutrients and the growth traits of P.sylvestris and P.tabulaeformis artificial plantations under different slope positions,slope direction and soil depth in eastern Liaoning were analyzed.The correlation coefficients in both of P.sylvestris and P.tabulaeformis artificial plantations low slope soil nutrient contents are higher than that of midslope and upslope.The correlation coefficient in shady-slope is higher than that of sunny slope.Soil nutrients in the P.tabulaeformis artificial plantations under low,shady slope has a significant positive related to soil organic C,soil total N,soil total P,soil available N and soil available P(p<0.05).Soil nutrients in P.tabulaeformis artificial plantations under low,shady slope had close relationships.And soil organic C,soil total N,soil total P,soil available N and soil available P are significantly positively related to each other(p<0.05).Soil nutrients in P.sylvestris artificial plantations under low,shady slope had close relationships.And soil organic C,soil total N,soil total P,soil available N and soil available P are significantly positively related to each other(p<0.05).