An interactive multiobjective approach to harvest decisions in forest planning

A hierarchical approach to forest planning is formulated, where harvest schedules are first determined, followed by a decision about harvest methods (harvest regime). Choice of harvest methods is particularly important because of concerns about harvest‐related site disturbance. In the decision model developed in this article, determination of a harvest regime is expressed as a multiple‐objective decision incorporating maximization of net present value and minimization of cumulative site disturbance for different site classes, subject to maintaining high levels of production, an even flow of timber, and avoiding adjacency violations. The search for preferred harvest regimes is performed interactively over a set of non‐dominated harvest schedules with alternative aspiration levels identified for the various objectives to reflect values of different stakeholders.     

多目标决策法在生态公益林资源优化配置中的应用研究

以定性分析为基础,以定量分析为核心,以生态、经济、社会效益最大为目标,运用多目标线性规划的方法,采用相应的数学模型,根据区域性生态经济的发展需求,确定生态公益林的林种结构优化方案,给出资源配置。     

The influence of forest data quality on planning processes in forestry

Abstract

Forestry planning relies on decision support systems for predicting and evaluating the outcomes of different management options. The accuracy of data describing the initial state of the forest will inevitably affect the projections of forest development and, hence, the quality of management decisions. As data acquisition is expensive, there is a trade-off between improving management plans and the increasing cost of gathering more data. This review attempts, from a critical perspective, to summarize research on how the quality of forestry data affects the results of forestry planning and decision making. It is structured as follows: first, the attempts to evaluate forestry data for forestry planning purposes are described, including methodology and main conclusions; secondly, some generic questions concerning how important aspects of this research area can be handled are posed and discussed; and finally, some conclusions are drawn, including methodological recommendations. It is concluded that research in this area is scarce, which is in contrast to the fields of forestry planning and forest data acquisition. The inherent complexity of forestry planning is probably the reason why those who seek to evaluate forestry data often oversimplify the problems.     

基于ArcGIS技术的森林防火辅助决策系统的研制

森林火灾扑救一直是我国森林防火工作的薄弱环节,为提高林火扑救的信息化水平,以中日防火项目为依托,以ArcObject组件为技术手段,研制开发了基于COM的森林防火辅助决策系统。该系统通过对林火行为模拟、火场损失预评估和最佳扑火路线的分析,实现辅助林火扑救、决策工作。     

森林资源灾害应急智能决策系统的概念结构探讨

森林资源是人类最宝贵的资源之一,重大、突发的森林资源灾害往往会严重地破坏森林资源,带来重大损失。森林资源灾害应急智能决策系统是应对这些森林资源灾害的有力手段。本文分析了建设该系统的必要性,提出了系统的概念结构,并探讨了其中各组成要素的作用,可为建立相关的系统提供参考。     

广西生态公益林主要树种植物热值与能量积累

应用氧弹式热量计进行广西公益林主要树种植物热值的测定,结合森林资源连续清查样地资料,估计广西公益林能量积累及其分配.结果表明:不同树种植物热值有差异,针叶林的热值略高于阔叶林,同一树种不同器官的热值亦有差异,叶的热值高于其他器官的热值,但植物热值的变幅多在18.19～22.72 kJ/g,测定结果与相关文献报道结果相符.广西公益林林分能量累积19 092亿MJ,按优势树种组分:杉木848亿MJ,占4.4％;松类1 754亿MJ,占9.2％;阔叶树16 490亿MJ,占86.4％.     

一种地区分销系统的利润优化模型及其算法

研究由一个地区分销中心和多个不同的零售商组成的地区分销系统,假设顾客需求是随机的价格弹性需求.在基于价格折扣的联合决策供应链契约下,由地区分销中心提供一个价格折扣,以系统各成员追求利润最大化为目标,建立了地区分销系统的利润优化模型,并给出了一种基于遗传算法的求解策略.最后,通过算例说明该模型的有效性.     

集体林调查规划体系的中欧比较分析

以按照欧盟技术规程编制的湖南省永顺县万坪镇战略森林规划为例,从森林资源调查、编案单位选择、方案的深度和广度、方案的检查评定4个方面进行了中国和欧盟森林资源调查规划体系的比较分析.森林资源二类调查存在的主要问题是调查面积大、精度低;间隔期长,时效性差;调查因子单一,难以满足编案要求.森林经营方案存在的主要问题是编案单位面积广,实施难度大;方案内容单一,针对性差;方法落后,科学性不强;深度不够,方案的可操作性差.笔者从改进调查体系、缩小编案单位面积、扩展规划内容、加强森林经营措施规划、提高民众参与程度和高新技术应用力度等方面提出了我国集体林区森林经营方案的改革思路.     

国家级森林资源遥感监测业务运行系统的设计

国家级森林资源遥感监测业务运行系统是在林区遥感影像高精度几何校正技术、林区地类信息的提取技术、森林类型、郁闭度和蓄积量信息的提取技术等关键技术进行攻关的基础上将森林资源遥感监测各环节工作进行集成的。通过此系统提供的遥感数据处理、森林分类判读、森林类型变化信息提取、遥感监测成果统计、地理信息分析与信息数据库管理等功能,充分发挥了遥感优势,达到了丰富监测信息,提高监测效率和工作效率的目的。     

卫星遥感数据在森林采伐监测中的应用

分别采用SPOT5、TM5影像前后两期多光谱遥感影像的波谱特征变化,检测森林资源变化信息,确定变化类型,以计算机自动识别对森林资源变化(减少)的区域(伐区)进行信息提取,并在此基础上进行室内人工预判读;结合采伐证、伐区作业设计、二类调查材料,进行补充判读,得出森林采伐图斑。古丈TM5(30 m分辨率)的面积正判率为96.3%;古丈SPOT5(10 m分辨率)的面积正判率为96.9%。实证分析表明,使用中、高分辨率卫星遥感数据能对森林采伐进行监测,结合辅助材料后能显著提高森林采伐监测精度。     

浅议萧山区森林结构优化与森林旅游业的发展

在分析森林结构优化的特点和可行性的基础上,针对萧山区依托森林资源发展的观光旅游业的现状,提出今后进一步优化森林结构和发展森林旅游业的4条措施。     

Assessment of logging moratorium using analytical network process in Iranian Hyrcanian forests

The aim of this research is to evaluate three forthcoming scenarios (continuing of forest management plans, logging ban, and forest management plans halt) in terms of policy change and select the best method based on sustainable forest management strategies in Iranian Hyrcanian forests. For this propose a two-layer evaluation process was considered for choosing the best alternative. Analytic network process as a decision approach is applied with Benefit–Opportunity–Cost–Risk (BOCR) merit. The data were obtained either from the previous research or through questionnaires. The results indicated that the benefits and risks were more important in terms of decision-making, compared to the opportunities and costs. Finally, the scenario of ‘continuity of forest management plans’ was selected as the most suitable alternative. The decision framework proposed in this study offers a rational means for decision-making of forest policy.     

森林收获安排模型研究进展*

森林收获安排是森林经营规划的核心问题之一。文中主要以美国的研究为代表．介绍目前森林收获安排模型的研究进展，包括：模型建立方法、模型分类和模型求解3个方面。模型的建立尚无统一方法。模型分为URM和ARM2类。模型的求解主要采用启发武搜索方法。指出．模型的发展趋势是资源保护空间优化模型。     

浅析我国森林资源清查体系存在的问题与对策

全国森林资源清查是通过定期、准确查清各省的森林资源数量、质量及其消长动态,从而掌握森林生态系统的现状和变化趋势,对森林资源与生态状况进行综合评价。由于清查覆盖面积大、跨度时间长,清查结果不能有效及时利用。本文浅析了我国森林资源连续清查体系在应用中存在的不足,并提出改进措施,以期为完善我国森林资源连续清查体系提供参考。     

浅谈森林资源二类调查的图形处理

文章介绍了森林资源二类调查图形资料的传统处理方法及其存在的不足，提出了以地理信息系统为平台的图形处理方法，并详细论述其处理过程，分析和总结了两种处理方法的效果，表明后一种处理方法的工作效率、准确性和计算精度高。     

西藏森林资源特点与林业发展思考

根据西藏自治区第二次森林资源二类调查结果,系统分析了西藏森林资源特点,客观评价了西藏林业发展状况,提出了西藏林业发展的基本思路,对于促进西藏现代林业的科学发展具有重要的现实意义。     

内蒙古自治区灌木林资源现状与保护发展对策

基于内蒙古自治区森林资源连续清查数据,以内蒙古自治区灌木林资源为研究对象分析了灌木林资源现状及动态变化,系统总结了灌木林资源的特点,提出了灌木林资源保护发展对策,为促进内蒙古自治区灌木林资源的保护与发展具有重要借鉴意义。     

Crown Density and Growth Relationships Between Stands of Picea abies in Norway

Relationships between the crown density and growth of Norway spruce (Picea abies L. Karst.) stands are presented, after removal of the effects of major natural influences. Crown density was assessed annually from 1991 to 1996 on 569 monitoring plots comprising 40000 trees. Stand growth was determined from measurements of diameter and height in 1991 and 1996. Various models explaining mean crown density and annual growth of the stands as a function of natural factors, such as age and site index, were compared. The influence of the natural factors was then removed by recalculating crown density to residual values from one preferred model, and by recalculating growth to relative values given as a percentage of model predictions. Crown density and its residuals were positively correlated to growth. These relationships were weak in terms of their ability to explain variation (low R²). However, the various relationships consistently indicated that approximately 1% change in crown density corresponded to 1% change in growth. This relationship also included common spatial variation over Norway: a large part of south - east Norway had unexplained low crown density and unexplained low growth. Some other, smaller regional consistencies were also found. The study supports the use of crown density assessments and encourages the use of growth data in the search for major stress factors responsible for present forest condition.     

美国森林资源清查的基本做法和启示

在简要回顾美国森林资源清查历史的基础上,重点阐述了美国森林资源清查的现状及特点,并针对我国森林资源清查的实际情况提出了有关建议。     

森林资源二类调查中MapInfo应用技巧探讨

MapInfo是一款著名的地理信息管理桌面系统,具有小巧灵活、使用简单、功能强大、价格适中的特点,非常适合森林资源二类调查中使用;通过合理定制工作流程、快捷键定义、快速配准、建立小班图层、MapBasic编程等技巧的应用,更能得心应手、简捷有效地处理小班信息。