3-PG模型在天然兴安落叶松林生长因子预测中的应用

Application of 3-PG Model in the Prediction of Growth Factors in Natural Larix gmelinii Forest

[目的]运用过程模型模拟天然林的生物量及蓄积生长。[方法]以大兴安岭落叶松天然林为研究对象,探索研究基于生理过程的动态模型3-PG模型在天然林中的应用情况,通过调整模型内置模块方程的参数,优化实测值与模拟值的拟合结果,最终得出适用于该地区落叶林天然林的模型参数组,并对不同林龄的林分预测效果进行了对比。[结果]模型在胸径、枝干生物量、根生物量、地上生物量、整株生物量的模拟取得了很好的效果,其中枝干生物量与整株生物量的模拟值与实测值的相关系数R2达到了0.98,且平均相对误差均控制在8%以内。对不同林龄林分的整株生物量与胸径预测结果表明,模型对3个龄组都有很好的拟合效果。[结论]在进行参数本地化调整后,3-PG模型可以运用在落叶松天然林的生长预测中,在生物量预测与胸径预测上可以取得较好的效果。

[Objective]To simulate and predict the biomass and volume growth of natural forest using process-based model.[Method]Taking Larix gmelinii natural forest in Daxing’anling mountains as the research object,the application of 3-PG model was studied based on physiological process in natural forest.By adjusting the parameters of built-in module equation of the model and optimizing the fitting results of measured value and simulated value,the model parameter group suitable for deciduous forest in Northeast China was finally obtained,and the test results of different forest ages were compared.[Result]The model achieved good results in the simulation of DBH,stem biomass,root biomass,above ground biomass and total biomass.The coefficient of determination R2 of stem biomass and total biomass equation reached 0.98,and the relative mean error was controlled within 8%.The results of total biomass prediction and DBH prediction for different aged forest showed that the model had a good fitting effect on young,half-mature and near-mature forests.[Conclusion]After adjustment of the local parameters,3-PG model can be applied to the growth prediction of natural L.gmelinii forest,and it can achieve good results in biomass prediction and DBH prediction.