Research Center of Environment and Sustainable Development, College of Environment, Tehran, Iran.
Department of Rangeland Management, College of Natural Resources, University of Tehran, Tehran, Iran.
Sci Rep. 2021 Jan 13;11(1):1124. doi: 10.1038/s41598-020-80426-7.
In managed forests, windstorm disturbances reduce the yield of timber by imposing the costs of unscheduled clear-cutting or thinning operations. Hyrcanian forests are affected by permanent winds, with more than 100 km/h which cause damage forest trees and in result of the tree harvesting and gap creation in forest stands, many trees failure accidents happen annually. Using machine learning approaches, we aimed to compare the multi-layer perceptron (MLP) neural network, radial basis function neural network (RBFNN) and support vector machine (SVM) models for identifying susceptible trees in windstorm disturbances. Therefore, we recorded 15 variables in 600 sample plots which are divided into two categories: 1. Stand variables and 2.Tree variables. We developed the tree failure model (TFM) by artificial intelligence techniques such as MLP, RBFNN, and SVM. The MLP model represents the highest accuracy of target trees classification in training (100%), test (93.3%) and all data sets (97.7%). The values of the mean of trees height, tree crown diameter, target tree height are prioritized respectively as the most significant inputs which influence tree susceptibility in windstorm disturbances. The results of MLP modeling defined TFM as a comparative impact assessment model in susceptible tree identification in Hyrcanian forests where the tree failure is in result of the susceptibility of remained trees after wood harvesting. The TFM is applicable in Hyrcanian forest management planning for wood harvesting to decrease the rate of tree failure after wood harvesting and a tree cutting plan could be modified based on designed environmental decision support system tool to reduce the risk of trees failure in wind circulations.
在管理森林中,风灾干扰通过强加计划外的砍伐或疏伐作业的成本来降低木材产量。咸海森林受到永久风的影响,风速超过 100 公里/小时,会对森林树木造成损害,结果是森林林分中的树木采伐和空隙形成,每年都会发生许多树木倒伏事故。我们使用机器学习方法,旨在比较多层感知器 (MLP) 神经网络、径向基函数神经网络 (RBFNN) 和支持向量机 (SVM) 模型,以识别风灾干扰中的易倒伏树木。因此,我们在 600 个样本中记录了 15 个变量,这些变量分为两类:1. 林分变量和 2. 树木变量。我们通过人工神经网络技术(如 MLP、RBFNN 和 SVM)开发了树木倒伏模型(TFM)。MLP 模型在训练(100%)、测试(93.3%)和所有数据集(97.7%)中表示目标树木分类的最高准确性。树木高度、树冠直径、目标树木高度的平均值的数值被优先视为影响风灾干扰中树木易倒伏性的最重要输入。MLP 建模的结果将 TFM 定义为识别咸海森林中易倒伏树木的比较影响评估模型,其中树木倒伏是由于采伐后剩余树木的易倒伏性所致。TFM适用于咸海森林管理规划中的木材采伐,以降低采伐后树木倒伏率,并且可以根据设计的环境决策支持系统工具修改树木采伐计划,以降低风循环中树木倒伏的风险。