Health Assessment Of Forest Resources In Minjiangyuan National Nature Reserve

With special geographic location and the great strategic significance in eco-environment construction,Minjiangyuan National Nature Reserve,which plays a key role in soil and water conservation,water resource conservation and climate regulation.The forest resources current situation of natural reserve region can be understood by health assessment of regional forest resources,meanwhile,effecting factors of forest health are revealed with pertinence,thus improving the forest ecological community with local conditions and putting forward some scientific suggestions on forest resources construction,development,management and application of nature reserve.Moreover,scientific operating and healthy development of forest resources in nature reserve,have important realistic meanings and unique value to protecting ecological environment,biodiversity and water system in the Minjiang River watershed.The data derived from the sub compartment of second type inventory of forest resources,Jianning County,Fujian Province in 2014 as well as the vector graphs of Minjiangyuan National Nature Reserve.And using field sample survey method to prefect forest inventory data,meanwhile,launching replenishment investigation to partial health evaluation factors.Furthermore,do health assessment research on 1 735 sub compartment,11 604.304 3 hm2 of forest resources in Minjiangyuan National Nature Reserve,and advance some corresponding suggestions.The main conclusions are listed as follow:(1)Sub compartment data can be divided into three kinds:"Incapable of qualitative and quantitative indexes","Both qualitative and quantitative indexes","Qualitative index".Based on some principles for index system establishment,finally constructing assess index system of health assessment of forest resources in Minjiangyuan National Nature Reserve by referring to literature and experts consultation method.Assess index system has three rule layers such as:productivity,organization structure,resistance and including 15 kinds of indexes:canopy density,shrub height,shrub layer coverage,herb layer coverage,hierarchical structure,average height,average DBH,per unit area of stock,soil thickness,thickness of soil humus,aspect,altitude,main tree species,tree species diversity mingling,human disturbance and so on.(2)Combining AHP and entropy method by comprehensive weight method in order to figure out comprehensive weight and obtains final weight value order:human disturbance(0.243 1)>hierarchical structure(0.178 5)>shrub height(0.092 2)>herb layer coverage(0.071 5)>canopy density(0.070 6)>tree species diversity mingling(0.063 0)>aspect(0.060 0)>main tree species(0.047 3)>shrub layer coverage(0.046 3)>altitude(0.030 6)>average height(0.029 3)>soil thickness(0.022 0)>stock of sub compartment(0.017 4)>thickness of soil humus(0.016 7)>average DBH(0.011 5).Therefore,human disturbance and hierarchical structure are main factors of assess index system of health assessment of Minjiangyuan National Nature Reserve.(3)Obtained each sub compartment comprehensive scores by weighted average method,and finally thus draw the conclusion that most forest resources in Minjiangyuan National Nature Reserve is within the health condition.Among them,the quantities of sub compartment in health,sub-health,mid-health,ill-health condition were 803,508,376,and 48,account for 46.28%,29.28%,21.67%and 2.77%,respectively,the areas of which were 6892.42 hm2,2 893.30 hm2,1 732.887 4 hm2 and 85.701 9 hm2,account for 59.40%,24.93%,14.93%and 0.74%,respectively.(4)Through contrast and analysis of health condition on land category,forest species,age group,and dominant species,the conclusion can be drawn that arbor forest is the healthiest of all land categories.The areas of healthy arbor forest is 6 706.107 1 hm2 which cover the 57.79%of total forest land area in natural reserve region;Forest for special purposes has the highest health level in all forest species,the area of which is 4 755.650 9 hm2,accounts for 40.98%of the total forest land;Mature forest has the best healthy condition in all age groups,whose healthy forest area is 3 908.276 1 hm2 which cover the 33.68%of total forest land area in natural reserve region;Broadleaved tree species is the most healthy in all dominant species,the area of which is 3 970.271 5 hm2,accounts for 33.21%of the total forest land.(5)Based on natural reserve region forest resources current situation and evaluation result,the constructive and purposeful suggestions of management are put forward,according to different health levels of forest.Concrete contents are as follows:Healthy sub compartment should be enclosed and forbidden for conservation,meanwhile,forbid human disturbance to its human disturbance.As for sub-health sub compartment should use artificial management and protection measures in main.Measures for intermediate cutting and replanting broadleaved tree species should be adopted in mid-health sub compartment.Methods of renovated-cultivation and dynamic monitoring should be applied in the ill-health sub compartment.