Development Of Multiple-purpose Decision Support Tool For Stand Density Management For Pinus Massoniana Lamb.Plantation

Pinus massoniana Lamb.is one of the most important tree species for timber in South China.The quantification of the management pattern and the improvement of the management level for Pinus massoniana plantation are of great significance to the achievement of sustainable forest management in Chinese southern forest regions.As a key technology for plantation management,stand density regulation serves as an important way to increase the productivity,maintain forest stability,and maximize forest function for plantation.Forestry decision support tool can play an effective role as a carrier for popularizing forestry theories and technologies and can transform them into productivity in planation management practices.Therefore,it is necessary to develop multiple-purpose decision support tool for stand density management for Pinus massoniana plantation.This paper takes the development of multiple-purpose decision support tool for stand density management for Pinus massoniana plantation as the main line,aiming to solve the first problem that the density management technology system is incomplete for Pinus massoniana plantation in the forest regions in Guangxi Zhuang Autonomous Region,and the second problem that it is difficulty for application and popularization of correlative stand density management techniques in the forestry production practices in the autonomous region.Based on the integration of density management theories and technologies,a multi-functional stand density management diagram(SDMD)was built based on the three period data from the pure Pinus massoniana forest plots in Experimental Center of Tropical Forestry(ECTF),Chinese academy of forestry,and the ordinary simulates for stand management were conducted,which could provide key models and core algorithms for the tool,respectively.Next,the comprehensive study of the rest of the algorithms that support the tool's functions was carried.On the basis of algorithm research,user needs were analyzed in depth.Based on the B/S mode and R programming environment,the overall architecture,user interface,functional structure and database of the tool were designed in conjunction with R shiny and other technologies of web data visualization.The tool was implemented and tested by two forms,i.e.,web application and local application.Finally,the paper analyzed the feasibility of the popularization of the tool in main producing regions for Pinus massoniana timber in the autonomous region.The main conclusions drawn from this paper can be summarized as follows:(1)Development of multi-functional stand density management diagram for Pinus massoniana plantationThe multi-function SDMD developed in this paper integrates a number of basic functions,such as harvest forecast for stand volume,biomass and carbon stock,risk assessment for wind disasters and canopy fires,etc.,which have filled the correlative technical gap that stand density management methods were used to judge and prevent the occurrence of wind disasters and canopy fires for planation in domestic.On the one hand,the multi-function SDMD and ordinary the algorithms for ordinary stand management simulates provide both key models and core algorithms for the decision support tool developed in this paper,one the other hand,they can also be used independently of the tool.(2)Development of multiple-purpose decision support tool for stand density management for Pinus massoniana Lamb,plantationThe function of the tool developed in this paper take multiple-purpose stand density management for Pinus massoniana plantation in the autonomous region as the core.In addition to the visualization of data,the tool effectively combined the functions of advice and assessment for afforestation density,plan establishment for tending thinning,calculation for economic profit,evaluation and early warning for current forest condition,etc..The online and offline implementation of the tool can meet the functional and non-functional requirements of the grass-roots foresters,and are applicable to various stand stages such as pre-forestation,young stands,and stands that have experience self-thinning.The tools can provide users with comprehensive service flow for stand density management from parameter input and function selection,calculation,analysis,judgment,tabulation,drawing to local or online saving and query,and can offer effective decision support for multi-purpose stand density management for Pinus massoniana plantations in ECTF.In conclusion,the tool developed by this paper can be helpful to achieve the quantification precision target in the process of stand density management for Pinus massoniana plantations in ECTF.Future,it can provide a feasible tool for quantitative management for Pinus massoniana plantation in Guangxi Zhuang Autonomous Region.