The Research Of Naturalization Management Models Of Larch Plantation In The Northeast Forest Region Of China

The structure,productivity,biodiversity and succession of larch plantation were studied by means of simple transect method and and a,βdiversity index methods in the eastern forestry region of Liaoning,furthermore,the roles that larch plantations played in the deteriorate climax vegetation restoration were assessed quantitatively,and its naturalization process and managing approaches were probed,so as to provide scientific basis for the management.The results showed that:①The community of larch plantation in Northeast Forest had obvious naturalization phenomenon,and was closely related with the site condition. respectively formed a vertical mixed forest by the composition of Larch(important value 0.605) and Fraxinus mandshuric(0.139),a level mixed forest by the composition of Larch(0.543) and Juglans mandshurica(0.156),and a "planting conifers and conserving broad-leaved trees" forest by the composition of Larch(0.528) and the Korean pine(0.338).②The plantation communities had quite high productivity and cost-effectiveness.Larch plantation volume in the Liaodong,the Changbai Mountain and Laoyeling Forests were 254.90,173.14 and 270.32 m~3/hm~2,productivity were 5.548,5.771 and 6.758m~3/a.hm~2;And its direct economic benefits were about 63897～112821 yuan/hm~2.③The plantation communities had high plant species diversity and community diversity.Northeast Forest larch plantation community,herb layer, shrub layer,the tree layer species richness distributed from 32 to 50,15 to 20,6 to 16,9 to 17, and the species diversity indnce distributed from1.3583 to 2.5192,1.1145 to 2.2895,1.0351 to 2.2060,1.2678 to 2.3045,and there was a close correlation with site condition,the the species diversity indnce along the bottom-up environmental gradient showed a general pattern of partial state(central＞bottom＞top).the community similarity coefficient was relatively low (the average value 0.496～0:600),and the species change rate(Cody index) was relatively high (the average value 13.00～18.75).④The succession result of the plantation communities will to be Korean pine hard broad-leaved mixed forests.Liaodong Forest will be Korean pine hard broad-leaved mixed forest dominated by Korean pine,Fraxinus mandshuric,Quercus mongolica,Ulmus davidiana and Acer mono.Changbai Mountain Forest will be hard broad-leaved mixed forest dominated by Fraxinus mandshuric and Acer mono.Laoyeling Forest will be hard broad-leaved mixed forest dominated by Fraxinus mandshuric,Quercus mongolica, Ulmus davidiana and Acer mono.⑤Three kinds of naturalization management models of Larch Plantation were put forward at last,on the basis of understanding the structure,productivity, biodiversity and succession of larch plantation communities,so as to make full use of its vanguard role in the community and its natural laws of succession,and to accelerat the recovery process of degradation forest vegetation.