Analysis on Trade-Offs and Synergies of Multiple Functions of Picea schrenkiana Forests in Central Tianshan Mountains

Objective: This paper was carried out to analyze the trade-offs and synergies among forest supply(productivity), regulation(carbon sequestration and oxygen release, water conservation)and support(biodiversity)functions in order to provide a theoretical basis for multi-functional forest management. Method: The study was implemented on Picea schrenkiana forests in the central Tianshan Mountains region of Xinjiang, based on the data from 42 sample plots and 1 170 sub-compartments in forest resources class Ⅱ survey of Banfanggou forest farm. Four functions, including stand productivity, carbon sequestration and oxygen release, water conservation and biodiversity, were predicted by using random forest method. The correlation analysis was made among the four functions of the stand, and the correlation of stand average age, stand volume, average tree height, average DBH, canopy density, slope, altitude, and vegetation coverage with these functions. Result: The main factors those have great influences on stand productivity, water conservation, carbon sequestration, oxygen release and biodiversity are stand average DBH, volume, vegetation coverage, average forest age and canopy density. The correlation coefficient is 0.225-0.917(P<0.01)between stand average age, tree height, DBH, canopy density, stand volume and four functions, comprehensive function. The correlation coefficient is 0.167-0.393(P<0.01)between slope and water conservation, carbon sequestration and oxygen release, biodiversity. The correlation coefficient between altitude and productivity, water conservation, comprehensive function is -0.264 - -0.143(P<0.01). There is a positive correlation between vegetation coverage and water conservation and biodiversity, the correlation coefficients are 0.237 and 0.081(P<0.01), respectively. The correlation coefficient is 0.228-0.645(P<0.01)with four functions, among which, the correlation between biodiversity and carbon sequestration and oxygen release is the highest. There is a synergistic relationship between the functions of the stands. Conclusion: There is a synergistic relationship among the four functions of Picea schrenkiana stands, harmonization of multiple functions could be achieved through rational forest management. © 2019, Editorial Department of Scientia Silvae Sinicae. All right reserved.