我国森林经营思想的演变和技术的发展

通过比较,分析限我国古代营林技术的发展历程,认为中国营林思想和技术发展历史悠久,许多领域达到了非常高的水平,许多实用技术至今仍被沿用。现代营林技术的进步,主要源主相技术的普及和基础理论的发展。今后仍将依杖生物和信息技术等新科技的渗透和实用化。现代经营思想在经过了法正林经营之后,更推崇自然林业和持续经营思想。虽然这一点与古代囿于生产力限制而遵循的自然林业思想有层次上的不同,但殊途同归,古今森林经营思     

社会发展与森林经营思想的演变

森林是人类生存和发展的摇篮,森林在人类的生存和发展过程中,起着不可替代的作用.随着社会经济的发展、科学技术的进步,人类在步入工业文明的相当长的一个时期内,对于森林与人类休戚与共的关系没有给予应有的认识和关注,全球范围内森林资源的持续减少和生态环境的逐步恶化,是导致当今人类社会生存和发展过程面临严重威胁的最重要因素之一.研究森林经营思想的发展变化,有利于从中吸取经验和教训,有利于正确地经营和管理森林,使林业的发展能够逐步满足人类对森林产品及其森林环境日益增长的需要,同时也有利于中国林业可持续发展的实践.     

森林经营思想的发展概况

对从森林永续利用到森林可持续经营思想的转变过程中几种典型的森林经营思想做一概略回顾。     

现代森林经营思想初探

森林曾经是人类诞生的摇篮、生存和进化的基础，现在森林在人类的生存和发展过程中仍然起着不可替代的作用。随着社会、经济的发展，科学技术的进步，人类在步人工业明后的相当长的一个时期内，对于森林与人类休戚与共的关系没有给予应有的认识和关注，不均衡的发展造成了资源的巨大消耗。全球范围内森林资源     

美国地方法官判决暂停布什政府的新森林法规

据《华盛顿邮报》2007年3月30日报道：加利福尼亚北部地区联邦地方法官密尔顿（Phyllis Hamilton）于30日做出以下裁决：布什政府2005年对1．92亿英亩的联邦森林和草原管理法的修改是非法的，并要求在提交新的政策计划时必须考虑对环境的影响问题。[第一段]     

人工林经营思想与经营模式

１ 近、现代有影响的森林经营思想与模式 从１８世纪末到１９世纪中叶，在英国爆发产业革命后，欧洲一些国家的资本家面对森林资源日益减少的严酷现实，为保证森林的均衡利用，不断追求高额利润，纷纷寻求采伐木材量入为出的办法，因此产生了森林永续利用和理财的想法，这就是森林经理学的雏形。 随着森林经理学的日臻完善和各种技术的采用，以法正林思想为技术核心的森林永续利用的概念和原则逐渐被各国林学界和产业界所接受，森林永续利用概念和思想成了近、现代森林经营思想的杰出代表。在当今世界面临资源环境和生存发展之间的矛盾日益…     

美国的森林旅游

美国的森林旅游赵海泉，赵建林森林公园和森林旅游起源于美国。１９７２年美国创立了世界第一个国家公园──黄石公园，首开现代人类森林旅游之先河。之后，美国国会于１９６０年通过森林资源多用途法，明确规定林地和草原的功能之一就是开展森林旅游；１９８７年开始制定...     

世界森林经营思想的演变及其对我们的启示

本文回顾了世界森林经营思想和实践的演变过程,对“森林的永续经营”和“森林的可持续经营”概念进行了诠释,同时指出“森林的可持续经营”概念目前已为世界上众多政治家和林业工作者所接受,从而成为当今世界森林经营的主体思想。作者还根据近年来国际森林问题的发展动态,就我国的林业发展提出了几点思考。作者认为,保持森林的环境保护与生产作用的平衡是至关重要的,在重视生态保护的同时,切莫忽略了森林的传统功能——生产。     

美国的城市林业

本文介绍了城市林业的内涵以及在美国的发展简史。作者还对其经营范围、法规制定、价值计算、行道树管理、教育和科学研究等作了阐述。     

美国耐旱景观实践及启示

在水资源日益紧缺的背景下,耐旱景观在世界范围内受到重视,其原则广泛应用于干旱地区的景观营造并获得了巨大收益。文中介绍美国耐旱景观及其原则,解析耐旱景观的内涵,列举美国耐旱景观实践的具体做法,希望通过美国耐旱景观的实践能够让更多地区的景观建设获得启示并从中受益。     

面向虚拟森林经营管理的树木交互式参数建模方法

从树木构筑概念出发,将传统的几何建模技术与树木形态结构结合,提出了一种交互式参数建模的方法.采用主干、枝条、叶片三类参数来描述和定义树木,约定了一系列的建模规则和参数化调节方法,并构建了一个树类.林业管理者通过输入熟悉的参数平台交互式地构建各种具有不同几何特征的树木,并且能够建立不同生长阶段的三维几何树模型,其模型简单且形态逼真,能够充分地表现树木的空间结构.     

Forestland ownership changes in the United States and Sweden

This article examines the changing structure and ownership of the forest products industry in North America and the Nordic countries. The authors explore company-specific perspectives on why some private forest products companies divest themselves of timberland ownership and others do not. The focus is on the United States, where the forest products industry has divested itself of substantial amounts of timberland, and on Sweden, where divestitures have been smaller. In both the United States and Sweden, forest products industries are large and forestland ownership has traditionally been an important component of the portfolio of an integrated forest products firm. The analysis presented here is based in part on literature about the vertical integration of markets.     

美国林业人才培养及启示

高层次林业人才培养是林业科学可持续发展的关键.美国高等林业教育在发展过程中积累了丰富的经验, 形成了较完备的教育体系.然而最近几十年来, 美国林业人才教育出现了一些值得关注的趋势, 一是某些早期的林业人才项目宣告提前结束或主动放弃认证资格; 二是研究型或具备博士学位授权的院校在逐渐收缩林业人才培养项目, 而科研力量相对较弱的大学却在逐渐增加林业教育项目.文中简述美国林业人才培养概况, 介绍美国林业人才培养项目的发展趋势, 分析美国人才培养所面临的挑战并探讨美国涉林院校对林业人才培养模式的调整, 提出我国林业人才教育培养的思考与启示.     

美国森林的水文效应

详尽综述了美国森林在涵养水源、改良水质和保障人民健康方面的作用和贡献,集中分析了国有林在水供给方面所扮演的重要角色——包括数量、质量、时空分布及防洪减灾等方面的经济价值.     

美国国有森林系统规划管理

美国的森林资源丰富且国有森林经营管理水平较高,其国有森林的权属清晰,管理理念先进,管理体系规范,法律法规健全,科学化经营程度高,森林多功能经营完善。美国最新的国有森林系统规划管理是在吸取了几十年的经验和教训之后提出的,旨在为人们和社区提供生态系统服务和多种用途,为当前和未来提供一系列的社会、经济和生态效益。文中介绍美国国有森林系统规划管理的背景和规划框架,分析其规划管理特点,总结其现行管理体系,并提出对我国国有林经营管理的借鉴意义。     

Silvopasture practices and perspectives in the Northeastern United States

The use of silvopasture systems on farms in the Northeastern United States has never been documented. Our objective was to gather baseline data to describe silvopasture practices and perspectives in the Northeastern United States. To accomplish this, we investigated the structure, management of, and reasons for use of silvopastures in New York state and New England through a series of interviews and inventories on 20 farms purposefully chosen as practicing silvopasture. Thematic content analysis was conducted to summarize interview results and identify trends related to silvopasture practices. Three farmers in this study had been practicing silvopasture on their farms over 30 years; the rest were new to silvopasture in the past 10 years. Only three of 20 farmers interviewed in this study had experience practicing silvopasture prior to implementing it on their farms. Forest conversion to silvopasture was the primary starting point for silvopastures observed on regional farms. Orchard, open field edge, outdoor living barn, and plantation silvopastures were also documented on multiple farms. Shade and a desire to maximize use of farm woodlands were primary reasons for silvopasture utilization. This research provides evidence that silvopastures are being used to diversify regional farms. For the practice to be advanced in the region further research is needed on the topic.     

Agroforestry and forestry-related practices in the Midwestern United States

A survey, conducted in 1990–1991 on agroforestry and forestry-related systems in eight Midwestern states, showed that three traditional and three nontraditional agroforestry systems are practiced in the region. Of 46 traditional systems reported, most common was agrisilviculture (28), then silvipasture (12) and agrisilvipasture (6). These systems often involved corn, soybeans, and hay planted with tree species for nut, timber, or Christmas tree production, and cattle. Non-traditional agroforestry systems were field windbreaks/shelterbelts (29), treeshrub intercropping systems (21), and boundary plantings (11). These systems involved a variety of northern hardwood species evergreens, and shrubs. There was also a preponderance of specialized systems (97) of growing trees with the production of mushrooms, nuts, syrup, wildlife, and other nonwood products. The survey is exploratory in nature and, although the results may not represent a complete count of people involved with agroforestry in the region, the numbers reported may indicate where a practice may be prevalent. The results reflect the fact that much work still needs to be done by agroforesters in this region. They also provide some basis for further research on more suitable systems, and for identifying other researchable questions on agroforestry for the region. The methodology also made possible a bigger nucleus for networking of agroforesters and other interested people in the Midwest. Finally, although not normally considered as agroforestry, the significance of the other specialized systems reported in this survey is that they offer varied ways of connecting forestry with other activities in a largely agricultural landscape, and that they may even be seen as opportunities for easier transition into agroforestry.     

Agroforestry practice and policy in the United States of America

Agroforestry practices and the policies influencing development and adoption within the United States are reviewed. Agroforestry is defined as ‘intensive land-management systems that optimize the benefits from biological interactions created when trees and/or shrubs are deliberately combined with crops and/or livestock’. The five agroforestry systems identified as having importance in the US are tree-agronomic crop systems (alley cropping and intercropping), riparian vegetative buffer strip systems, tree-animal systems (silvopasturing), forest/speciality crop systems (forest farming) and windbreak systems (shelterbelts). A lack of federal policy relating specifically to agroforestry exists. If agroforestry is to achieve its full potential in the United States, adequate financial, institutional and technical support for its development must be provided.