Evaluation On Nanning Arboretum's Public Welfare Forest And Commercial Forest Ecological Service Function

For the purpose of better protecting the forest resources and giving play to the ecological service function of different types of forests,the forests are classified into non-commercial forest and commercial forest in China according to their dominant function.It is of great practical significance for protecting,reasonable utilizing and sustainably developing forest resources through the approach of classified studies of the service function and economic value of non-commercial forest and commercial forest.In this paper the author will expound the service function and evaluation mechanism of forest ecological system,and adopt appropriate measurement theory and indicator system based on actual requirement to quantitatively study the ecological service function of non-commercial and commercial forests in Nanning Arboretum of the Guangxi Zhuang Autonomous Region(based on the date of 2009,2013 and 2017).Through field survey,statistical calculation and inductive analysis,to learn the ecological service function values,dynamic changes and differences of the two types of forests,which can effectively improve people's understanding of the necessity and importance of protecting the forest ecological environment,and meanwhile provide theoretical support for solving problems in the development of plantation forests(commercial forests).The main research results of this paper are as follows:1.The present(2017)total value of the ecosystem services function in Nanning Arboretum is 3.4832×1010 yuan/a,and the value per unit area is 1.4738 X 107 yuan/(hm2 a).The indirect value(3.4829×1010 yuan/a)is 12543 times of the direct value(2.7767×106 yuan/a),which highlights the main features of Nanning Arboretum that operated as a forest park.2.The total value of the non-commercial forest ecosystem service function in Nanning Arboretum is 1.3700 × 1010 yuan/a,and the value per unit area is 9.7478 X 106 yuan/(hm2 a);the total value of commercial forest ecosystem service function is 3.4695 × 1010 yuan/a,and the value per unit area is 3.6225×107 yuan/(hm2 a).The total value of commercial forest ecosystem service functions is 2.53 times that of non-commercial forests,and its value per unit area is 3.72 times that of non-commercial forests.3.The ranking of each ecological service functions value of the two types of forests in Nanning Arboretum is slightly different.For non-commercial forest:oxygen-generating function>carbon sequestration function>reduce soil nutrient loss function>species conservation function>dust retention function>reduce soil sedimentation function>cultural function>water purification function>products providing function>regulating water amount function>sulfur dioxide absorption function>provide anion function;For commercial forest:oxygen-generating function>carbon sequestration function>reduce soil nutrient loss function>species conservation detention>dust retention function>reduce soil sedimentation function>products providing function>water purification function>regulating water amount function>sulfur dioxide absorption function>provide anion function>cultural function.4.Comparing the ecological service function value of Nanning Arboretum non-commercial and commercial forests in different years shows that in 2009,commercial forests was superior than non-commercial forest in the functions of products providing,water amount regulating,water purification,soil sedimentation reducing,anion providing,dust retaining and oxygen-producing.In 2013,commercial forest only had advantages in the functions of carbon sequestration,anion providing,dust retaining and oxygen producing,and the advantageous index also decreased significantly compared with 2009.In 2017,commercial forest has only five indexes are higher than that of non-commercial forest which including product providing,carbon sequestration,anion providing,dust retaining and oxygen generating,but its overall advantages were further reduced.5.With abundant tree species and complex stand structure,the plant species and species conservation value of non-commercial forest in Nanning Arboretum is much higher than that of commercial forest.For example,in 2009,the ecosystem species conservation value of non-commercial forest was 6.2919 X 107 yuan/a,which was 15.0 times of the commercial forest(4.4298 X 106 yuan/a)in that year;in 2013,the ecosystem species conservation value ofnon-commercial forest was 7.3577×107 yuan/a,which was 26.0 times of the commercial forest(2.7900×106 yuan/a)in that year;in 2017,the ecosystem species conservation value of non-commercial forest was 7.4420 × 107 yuan/a,which was 25.9 times of the commercial forest(2.8734 × 106 yuan/a)in that year.