Structure-based Spatial Optimization Management Model For Natural Uneven-aged Forest

Natural uneven-aged forest has very important ecological, economical and social value. Experienced all sorts of unreasonable management and interference, it need so long time to recover to a healthy and stable state if only rely on the power of nature. Therefore the advanced management need to be operate on to promote the optimization and sustainable development of Natural uneven-aged forest.This research discussed how to optimize the stand spatial structure using computer, in order to promote the Natural uneven-aged forest to realize the sustainable development, with the aid of structure-based forest management and all kinds of spatial structure parameters. In this study, Spatial Structure Optimization Model (SSOM) is established, and SSOM software is programming. The management plans of Natural uneven-aged forest, came from management model and forester, are evaluated.In this research, the mean mingling value of stand contains the species number in structure unit after parameter modification, keeping the original class definition of structure unit, which explain the species mixing without confusion, and illustrate the species diversity and isolation degree simultaneously. Two new parameters are established, one is Open Comparison, which explain the light environment with the ratio of two neighbor's horizontal distance and hight difference, the other is Open-Close index, which explain sparsity or crowdedness of the trees crown layer with the ratio of two neighbor's horizontal distance and their crown width.The target of SSOM is spatial structure optimization, signed by the objective function got the minimum value, under the spatial structure and non- spatial structure constraint, and using partial exhaustive method.Analyzing the priority order of management measures, the computer management rules have been established. According to the overall goals and principles of structure-based forest management, the priority order of management urgency factors is: tree health > Climax Species Dominance> stand distribution pattern> the species diversity> stand species composition> tree maturity. The conditions of natural China Ash-korean pine forest, including spatial and non-spatial structure information, located in the northeast Jilin Jiaohe were evaluated by kinds of index, such as the Mingling, Uniform Angle Index, Neighborhood Comparison, Species Dominance, Open-Close index, Open Comparison, species diversity, diameter distribution, Canopy density, and so on. Management consulting results showed the mentioned forest is a secondary forest, and its management urgency is in the Middle Urgency. The management direction is to improve the Climax Species Dominance, cutting some big trees appropriately and taking care natural regeneration.Management results showed both of the field management and SSOM management had achieved the management goals of spatial structure optimization, that means the Climax Species Dominance improved, their pressure of competition reduced, and the composition of species adjusted to a certain extent, and the continuous canopy maintained, at the same time the species diversity and structure stability of stanf protected, at last a certain number of wood obtained. Each management methods have their own business scope. To satisfy all constraints, SSOM controls spatial structure in the the whole situation and achieves the optimization objectives. Furthermore, it can use the complete information of forest spatial structure to explore the spatial structure optimization rules, which can be used by forester to formulate the corresponding operation per trees, in large-scale non- position-data field management.