Tree health mapping with multispectral remote sensing data at UC Davis, California

Tree health is a critical parameter for evaluating urban ecosystem health and sustainability. Traditionally, this parameter has been derived from field surveys. We used multispectral remote sensing data and GIS techniques to determine tree health at the University of California, Davis. The study area (363 ha) contained 8,962 trees of 215 species. Tree health conditions were mapped for each physiognomic type at two scales: pixel and whole tree. At the pixel scale, each tree pixel within the tree crown was classified as either healthy or unhealthy based on vegetation index values. At the whole tree scale, raster based statistical analysis was used to calculate tree health index which is the ratio of healthy pixels to entire tree pixels within the tree crown. The tree was classified as healthy if the index was greater than 70%. Accuracy was checked against a random sample of 1,186 trees. At the whole tree level, 86% of campus trees were classified as healthy with 88% mapping accuracy. At the pixel level, 86% of the campus tree cover was classified as healthy. This tree health evaluation approach allows managers to identify the location of unhealthy trees for further diagnosis and treatment. It can be used to track the spread of disease and monitor seasonal or annual changes in tree health. Also, it provides tree health information that is fundamental to modeling and analysis of the environmental, social, and economic services produced by urban forests.     

The Role of Lumber Networks in Forest Devastation: Economic Sociology of Rural Forest Household Business in Japan

In this article, I utilize the perspectives of economic sociology to examine the structural background of forest devastation in Japan. First, I explore the factors behind cited problems for the forestry industry and demonstrate that expanded imports of inexpensively priced foreign-sourced logs do not sufficiently explain those issues. On that basis, I then demonstrate that the concepts and analytical tools offered by economic sociology are essential to a full understanding of relevant problems. Next, to understand how the current crisis differs from that experienced by forestry households in the 1980s, I turn my focus to changes in the social networks that supported the trade in wood products. The crisis witnessed a transformation that involved disembedding sawmills from the traditional wood trading networks that had relied on cooperative ties with forestry households. Eventually, social relationships between forestry households and sawmills were severed and these households became unable to address their economic difficulties through their existing practices. Given that context, I then examine the contrasting economic behavior of sawmills and forestry households and demonstrate that exposure to global price competition forced forestry households into uncontrolled over-cutting. Finally, I assert that economic sociology is better able to provide a more precise understanding of the true nature of the problems facing forestry in modern-day Japan than conventional economics with its adherence to the useful but insufficient principles of market competition and economic efficiency.     

清代湖北木材贸易研究

清代是我国传统木材市场快速发展的时期,木材流通与贸易频繁。湖北地处长江中游地段,有着丰富的木材资源,是发展木材贸易的主要基础。省会城市武汉,水路交通便利,素有“九省通衢”之称,在清末发展成为全国著名的木材集散中心。全国各地的木商云集于此,有着发达的木商组织,同时拥有发达的金融机构为其提供资金周转贸易,支持长途运输木材,故木材销量大,辐射面广。湖北木材贸易集湘、黔、川之木材,输往江南、京师要地,为当时园林建设、运河堤坝的巩固、城市发展等做出了巨大贡献。通过对这段历史的回顾,有利于摸清当时木材贸易的规律,为我国当前林业发展提供一定的借鉴。     

论我国木材经营加工许可制度改革

木材经营加工产业是一项古老的产业,也是现代林业产业体系中的重要产业,具有极大的发展空间。当前,中国木材经营加工产业发展面临诸多的制度瓶颈,林业行政部门在实施木材经营加工许可制度时存在扩大管制地理空间、压缩木材经营加工企业市场空间、随意设定行政许可有效期和年检等问题。要发展木材经营加工产业,最优选择是取消木材经营加工许可制度,次优选择是全面规范木材经营加工许可制度,包括严格控制地理空间范围、简化木材经营加工许可申请材料、取消年检等。     

“第三部门”视野下的福建集体林业产权制度改革

福建集体林业产权制度改革进入第二阶段后,随着广大林农自治能力的逐步提高,市场和政府不能涵盖的林业生产领域方面出现了"第三部门".本文对"第三部门"的出现、现状及其存在的问题进行了经济分析,并在此基础上,提出要加强对"第三部门"的制度支持与约束,完善提高"第三部门"自身参与能力的政策措施.     

再论现代林学、森林与林业——对北京林业发展之初议

本文论述了林学、森林和林业近两个多世纪以来的发展变化。林学经历了由传统林学向现代林学的转变。现代林学是以森林生态系统的营建、恢复、改造、经营管理和合理利用为研究对象和内容,以全面发挥森林生态系统的多功能和多种效益为目的,并做到森林可持续发展、永续利用的学科。对森林的认识也经历了由单株树木到树木群体再到森林生态系统的变化,森林对环境的影响由局部影响转向深入研究森林对大范围包括国家、洲及全球的影响。特别是热带森林有地球的“心脏”、“肺”之称,影响全球。人们对林业的认识也从长期以木材利用为中心,转变到全面发挥森林多功能、多效益的复合产业和公益事业,以实现森林的永续利用和可持续发展。本文还对北京林业未来发展的定位、布局、质量及多功能经营问题,提出了一些新见解。     

关于积极推进森林生态文化体系建设的几点思考

森林生态文化建设不仅是和谐文化体系构建的重要组成部分,也是现代林业建设的内在要求,更是人与自然和谐、人与社会和谐、人与人和谐的重要实践。本文就生态文化体系建设的意义、森林生态文化的内涵、森林生态文化体系建设的主要内容、主要措施四个方面进行了详细阐述。     

战略管理会计在林业企业管理中的应用

我国林业企业管理远远不能适应激烈的竞争环境,不能满足建立现代化企业的要求。本文对林业企业应用战略管理会计的紧迫性、应用过程中存在的难点问题进行讨论,并提出一些建议。     

现代生态景观视野下城市树木价值计算方法

城市树木是城市有价财产,价值体现在木材产品和生态服务两个方面.为了能够通过货币来表达和评估城市树木的实际价值,通过参考国外城市树木价值计算方法、森林树木价值研究成果、政府官方网站数据、国际木材价格以及咨询城市林业专家的方法,提出城市树木价值计算公式：城市树木的价值=胸高（1.3m）树干断面积×树木基价×树种系数×生长位置系数×生长情况系数×观赏特性系数×生态效益系数,并确定计算公式中的树木基价以及系数赋值的方法和标准.     

林业信息工程本科人才培养体系研究

林业基层信息化人才的紧缺,对林业高等院校人才培养提出新的要求。研究构建林业信息工程本科人才体系框架,解决＂培养什么人＂和＂如何培养人＂的问题,重点从人才培养目标影响因子进行分析,从而界定了林业信息工程本科人才培养目标;为优化人才的知识结构、能力和素质结构,构建了林业信息工程本科人才培养课程体系。