CHEN Shulin，WEN Zuomin

(College of Economics and Management，Nanjing Forestry University，Nanjing 210037 China)

Estimating Forest Ecosystem Service Function and Its Value of Soil Carbon Sequestration under Different Tree Species in Guangxi Province：Take Raw Material Forest of Stora Enso Bases for Example

CHEN Shulin，WEN Zuomin

(College of Economics and Management，Nanjing Forestry University，Nanjing 210037 China)

Background Manmade Forest plays an increasingly important role in soil carbon fixation function of forest ecosystem in China．Eucalyptus (Eucalyptusrobusta) plantations bring considerable economic benefits，but they also lead to functional degradation of forest ecosystems．Therefore，study on the forest ecosystem service function and its values of soil carbon sequestration under the Eucalyptus plantations have become an urgent problem faced by Guangxi forest management department．

Methods Gaofeng forest farm and Qipo forest farm are 2 raw material forest bases in stora enso．Eucalyptus plantations，Masson pine (Pinusmassoniana) forest，and Chinese fir (Cunninghamialanceolata) forest are 3 species in the study area，and 207 sample plots were selected according to the factors as tree species，slope，aspect，etc．In each sample plot，we measured the soil organic matter content by the potassium dichromate volumetric method，and determined the soil bulk density by ring knife method．Meanwhile，sample plots are divided into two parts，one part contains 157 points for space interpolation processing，and the other part contains 50 points which were used to verify the accuracy of the interpolation results．Then，we used Kriging interpolation method to estimate the soil organic matter content in the raw material forest bases of stora enso．

Results We used the soil organic matter content which were collected from 50 sample plots to verify the interpolation results，and the results show that the simulated soil organic matter content was consistent with the observed soil organic matter content．It means that Kriging interpolation method is suitable for the soil organic matter content estimation in the raw material forest bases of stora enso．The results also show that the soil organic matter content of distribution in the southwestern areas was lower than the northeastern regions．The averaged soil organic matter content was 4.57%．As results of calculating soil organic carbon storage，the total of the soil organic carbon storage was 7.03×105t．The largest averaged soil organic carbon storage per unit appeared under the Eucalyptus plantations (36.38 t/hm2)，followed by the Masson pine forest (35.02 t/hm2)，and the Chinese fir forest having the smallest averaged soil organic carbon storage per unit (33.37 t/hm2)．It means that Eucalyptus plantations is the fast-growing and high-yield tree species with strong soil carbon sequestration ability，and its soil carbon storage capacity is higher than that of Masson pine forest and the Chinese fir forest．According to the standard proposed by the State Forestry Administration of the People’s Republic of China，we evaluated the value of the forest ecosystem service function of soil carbon sequestration in the raw material forest base of stora enso．The results show that the total value of the forest ecosystem service function of soil carbon sequestration was 8.43 billion yuan．The largest averaged value of the forest ecosystem service function of soil carbon sequestration per unit appeared under the Eucalyptus plantations (4.37×106CNY/hm2)，followed by the Masson pine forest (4.20×106CNY/hm2)，with the Chinese fir forest having the smallest averaged value of the forest ecosystem service function of soil carbon sequestration per unit (4.00×106CNY/hm2)．

Conclusions and Discussions This paper used the plot survey method and the Kriging interpolation method to estimate the value of the forest ecosystem service function of soil carbon sequestration in Stora Enso's raw material forest base．The results show that the soil organic carbon storage and its value pur unit area under the three different tree species from high to low was Eucalyptus plantations >Masson pine forest >Chinese fir forest，and this is consistent with other studies which used the plot survey method．The total amount of the soil organic carbon storage was 7.03×105t，and the value of it was 8.426 1 billion yuan．

soil carbon sequestration；value estimation；Kriging interpolation method；spatial pattern；tree species

Original Articlein陳書林，溫作民．桉樹人工林不同樹種土壤固碳價值評估：以廣西斯道拉恩索公司兩個原料林基地為例．林業(yè)經(jīng)濟(jì)問題，2017，37(2)：35-38，44．

10.16832/j.cnki.1005-9709.2017.02.007