美国的城市林业

美国是世界上都市化程度较高的国家之_。今天,生活在城市的人口己占美国人口的3/4以上。城市林业在美国市民生活中起着非常重要的作用。 本文介绍了美国城市林业的历史、内含、管理,还介绍了美国部分城市各种不同用地类型(包括住宅区、商业区、工业区、学校、公园、隙地等)的森林复盖率,城市林业职业教育和城市植树的经费来源。     

珠海生态示范区建设与城市可持续发展对策

文章以珠海生态示范区建设为对象，重点探讨了生态示范区建设与城市可持续发展的关系，从生态资源的合理开发利用，生态环境与经济的关系，生态工程建设，环境管理等方面提出了相应的对策建议。     

林业持续发展与高效林业

王永安教授惠寄本刊的新作—“林业持续发展与高效林业”,从林业的生态效益、社会效益、经济效益的新角度出发,阐明了高效林业的基本概念,即高效林业的关键在高效;提出了高效林业是现代林业的重要标志,是21世纪环境发展中资源—环境—人口协调的重要方面,是林业溶于社会的必由之络;指出了发展高效林业应具备的基本条件,即在不同林种,不同功能,不同类型的时间、空间分配差异的森林实施不同发展途径和方法;论述了实现高效林业的途径和指标体系。这些新的观点对指导林业生产,发展高效林业、增强森林生态功能等具有重要的指导意义和现实意义。     

基于人均生态承载力的安徽省资源环境公平性研究

通过对人均生态承载力内涵的扩展,提出了生态承载系数的概念。从多个时间断面出发,计算2001—2010年安徽省17个地市的人均生态承载力,并选取能源消耗、水资源消耗、SO2排放和COD排放4个评价因子,构建基于人均生态承载力的安徽省资源环境基尼系数和生态承载系数的计算与评价方法。结果表明:(1)安徽省SO2排放的资源环境基尼系数高于0.4的警戒线,能源消耗的资源环境基尼系数接近0.4的警戒线,水资源消耗和COD排放的资源环境基尼系数均处于相对平均等级。(2)总体来看,省内资源型城市马鞍山、淮南,经济较发达城市合肥和沿江工业城市安庆、芜湖是安徽省资源消耗和污染物排放不公平性的主要因子,需要优化资源环境分配;皖南山区城市黄山、池州和宣城是安徽省资源消耗和污染物排放公平性的主要因子。该研究可为安徽省资源环境安全性评估和分配提供理论依据。     

国际环境技术中心(IETC)在城市环境和淡水管理中的作用

背景和情结国际环境技术中心(IETC)由联合国环境规划署(UNEP)建立，1994年4月开始工作.办事处设 在日本的两个城市：大阪市和志贺县草津市.该中心隶属联合国环境规划署技术、工业与经济司(UNEP DTIE)，主要职能是推动对环境 有利的技术(ESTs)应用于发展中国家和过渡经济国家的城市环境与淡水资源管理的工作.IET C尤其关注诸如废水、污泥、空气污染和一体化市政废物管理等城市环境问题和淡水资源管 理.IETC的委任依据21世纪议程.因此，IETC实行一种结果取向的工作计划，包括：◆改善ESTs信息的检索；◆促进技术合作、伙伴关系…     

城市人口与城市环境

人口问题是其他问题(资源、能源、粮食、环境)的主要根源。城市人口与城市环境的关系密切。本文从世界、全国、湖北省及武汉市的人口发展分析,指出城市环境的研究核心问题是城市生态系统。提出今后城市应用生态和理论生态学方面可开展研究的内容,以及城市生态系统的调控中应注意应用耗散结构理论、协同论和黑箱方法。研究城市化的过程,重点应是城市人口的增长和分布、土地利用方式、工业化过程、目前的水平和趋势。适宜的人口密度及其良好素质,可提高社会经济活力,提高城市的经济效益,有利于搞好城市环境保护。     

国际环境技术中心 (IETC)在城市环境和淡水管理中的作用

背景和情结 国际环境技术中心 (IETC)由联合国环境规划署 (UNEP)建立， 1994年 4月开始工作 .办事处设在日本的两个城市：大阪市和志贺县草津市 . 该中心隶属联合国环境规划署技术、工业与经济司 (UNEP DTIE)，主要职能是推动对环境有利的技术 (ESTs)应用于发展中国家和过渡经济国家的城市环境与淡水资源管理的工作 .IETC尤其关注诸如废水、污泥、空气污染和一体化市政废物管理等城市环境问题和淡水资源管理 . IETC的委任依据 21世纪议程 .因此， IETC实行一种结果取向的工作计划，包括： ◆改善 ESTs信息的检索； ◆促进技术合作、伙伴关系、采纳和使用 ESTs；和 ◆能力建设 . 任务 IETC的任务以城市环境和淡水管理为中心 .该中心采取下列措施，使水和城市环境管理一体化： ◆增强意识； ◆信息交流； ◆能力建设； ◆示范项目 . IETC的活动集中于： ◆通过识别和解决环境问题支持政府和其它组织机构； ◆评估新技术应用解决当前问题的可能性； ◆在发展中国家推广和示范对环境有利的技术 . 过去 IETC的活动包括： ◆出版《西亚淡水扩充的可利用技术》和建立一个 EST数据库， maESTro; ◆开展中国洱海与西洱河流域调查研究，为帮助区域可持续发展制定投资计划； ◆举办湖泊水库防治海藻污染规划和管理问题讨论会并提供说明书； ◆举办采纳、应用和管理工业和家庭废水处理 ESTs区域讨论会； ◆编制城市环境管理系统综合方案； ◆发行一本废水和雨水可持续管理的资料手册 . IETC现在在下列领域开展活动： ◆用于建筑和城市化的环境有效的技术；◆城市中受污染和废弃的土地； ◆开沟技术； ◆城市能源和水利用效率； ◆城市温室气体 (GHG)排放、空气质量管理和城市运输； ◆作为可持续生态系统的城市开发； ◆城市和地方政府当局的环境管理系统； ◆水的回收与再利用； ◆植物技术与生态系统管理 . 要了解与城市环境和淡水资源管理有关的 IETC及其活动的详情，请与国际环境技术中心 (IETC)联系，联系地址： 2－ 110 Ryokuchi koen,Tsurumi ku,Osaka 538 0036,Japan.Tel:＋ 81(6)6915 4580:Fax:＋ 81(6)6915 0304;ietc@unep.org.jp;http://www.unep.or.jp 什么是 maESTro? maESTro是一个数据库，包含有关各种各样环境技术、组织机构和信息来源，这些信息涉及城市环境和淡水管理领域的空气和水污染、环境管理、人类住区、有毒物质的再循环、固体废物、废水、水的扩充和更多的利用 .这些信息由 IETC以及 EST的贡献者、各别使用者和各种组织与机构定期更新 . maESTro首先作为一种信息工具开发，以软磁盘、 CD ROM和报告 (硬拷贝 )形式免费传播对环境合理技术 (ESTs)的信息 .在 1998年 3月，应 maESTro的用户的请求， IETC决定进一步开发 maESTro，以便人们可以通过因特网检索它 . 技术可以是“硬”的，“软”的，也可以是以自然为基础的或人造的 . 所包含的所有信息可与其他 maESTro用户共享 .欢迎所有 maESTro用户通过 web、 e mail或 /定期邮件登录他们自己的资料，以便用户可通过这一交互式数据库交流信息 . EST的供献者 1996年以来， maESTro有幸与很多政府部门合作，包括新西兰环境部，蒙古资源与环境部，立陶宛环境保护部，印度环境与森林部，巴林住房、市政与环境部，黎巴嫩环境部，厄立特里亚能源与矿产部，和大韩民国环境部 . 促进 EST相关信息交流的 maESTro其它贡献者包括设在奥地利的联合国工业发展组织 (UNIDO)，日本全球环境中心基金 (GEC)，美国的环境保护局 (EPA)和加拿大安大略环境技术促进中心 (OCETA)等 .     

鹿特丹公约:为什么在这里和它试图达到什么目的?

在二十世纪,各种合成化学品的使用有着令人注目的增长,特别是在制造产业和农业中.这些化学品中有许多后来显示出大量的不合乎需要的特性,包括在环境中的持久性,在食物链中生物放大的趋势,对于环境的负面影响.某些化学品也显示导致癌症或出生率下降.有些是非常危险的,即使在非常有限的暴露之后.在1970年代和1980年代所关切的是在一些国家中采取的禁止或限制某些有效化学品的使用,例如可能导致当这些化学品被出口到其他制定规章、基础结构和资源不足的国家时出现的管理它们的风险.为了响应这些关注,联合国粮食与农业组织(FA O)开发了自愿的…     

基于企业环境经营的生态环境管理效益探讨

现阶段,生态环境破坏程度日趋严重,环境规制越来越严格,企业作为环境资源的主要消费者,不得不寻求更好的经营理念,来实现其经济效益和环境效益的协调,提升其市场竞争力,实现企业目标。由此,环境经营的新理念应运而生。与传统的经营理念相比,新兴的环境经营理念,把环境视为企业发展要素,视环境为资源,把环境保护当作企业的重要经营服务活动,争取地球资源的循环利用,与环境和谐相处,完全改变了企业与环境原来的关系。环境管理效益则是企业环境经营活动所产生的效果或效应。企业通过主动推进前瞻性环境经营,能最大程度地提高环境管理效益。     

基于投影寻踪的广东省资源环境绩效评估与分析

采用基于投影寻踪的资源环境综合绩效指数（REPIPP）,对2007年广东省各市的资源环境绩效进行了评估与分析。研究结果表明,全省资源环境绩效水平空间差异明显,呈现珠江三角洲地区高于东西两翼和粤北地区、沿海城市高于内陆城市的特点,与广东省的区域经济发展格局基本一致;在各项指标中,工业固废排放绩效的权重较大,落后地区应特别注意加强环境保护和发展循环经济,减少工业固废排放;REPIPP与人均GDP具有一定的正相关关系,但并不完全由人均GDP决定,必须通过优化经济结构、增强科技创新水平和管理水平、加强环境保护等综合措施来提高资源环境绩效水平。     

Effects of national forest‐management regimes on unprotected forests of the Himalaya

Globally, deforestation continues, and although protected areas effectively protect forests, the majority of forests are not in protected areas. Thus, how effective are different management regimes to avoid deforestation in non‐protected forests? We sought to assess the effectiveness of different national forest‐management regimes to safeguard forests outside protected areas. We compared 2000–2014 deforestation rates across the temperate forests of 5 countries in the Himalaya (Bhutan, Nepal, China, India, and Myanmar) of which 13% are protected. We reviewed the literature to characterize forest management regimes in each country and conducted a quasi‐experimental analysis to measure differences in deforestation of unprotected forests among countries and states in India. Countries varied in both overarching forest‐management goals and specific tenure arrangements and policies for unprotected forests, from policies emphasizing economic development to those focused on forest conservation. Deforestation rates differed up to 1.4% between countries, even after accounting for local determinants of deforestation, such as human population density, market access, and topography. The highest deforestation rates were associated with forest policies aimed at maximizing profits and unstable tenure regimes. Deforestation in national forest‐management regimes that emphasized conservation and community management were relatively low. In India results were consistent with the national‐level results. We interpreted our results in the context of the broader literature on decentralized, community‐based natural resource management, and our findings emphasize that the type and quality of community‐based forestry programs and the degree to which they are oriented toward sustainable use rather than economic development are important for forest protection. Our cross‐national results are consistent with results from site‐ and regional‐scale studies that show forest‐management regimes that ensure stable land tenure and integrate local‐livelihood benefits with forest conservation result in the best forest outcomes.     

The progress and challenges in sustainable forestry development in China

Forestry development in China has undergone a series of reforms over the past six decades. This article examines temporal changes in forest resources and policies, the current status of forestry, and future challenges toward sustainable forest management in China. Excessive logging in the 1950s to 1980s badly damaged the nation’s forests, but the adoption of enlightened forest policies in the late 1990s has led to increases in China’s total forest area and growing stock. Forest degradation was ecologically and economically costly, and rehabilitation processes have become increasingly more expensive. The low quality and young age of forest resources, loss of natural forests, and more difficulties in afforestation and reforestation pose severe challenges for China’s sustainable forestry. It is critically important for China to enhance forest productivity through intensive management, strengthen enforcement, and educational programs for protecting and restoring natural forests, narrow the gap between domestic timber supply and rapidly expanding consumption, improve coordinating networks for management, finance, and technology transfer, and accelerate efforts to clarify and stabilize tenure arrangements for non-state forests. China’s experience and lessons in forestry may be helpful for other developing countries that are seeking to achieve the goal of sustainable forest management.     

Biodiversity Differences between Managed and Unmanaged Forests: Meta-Analysis of Species Richness in Europe

Abstract: Past and present pressures on forest resources have led to a drastic decrease in the surface area of unmanaged forests in Europe. Changes in forest structure, composition, and dynamics inevitably lead to changes in the biodiversity of forest‐dwelling species. The possible biodiversity gains and losses due to forest management (i.e., anthropogenic pressures related to direct forest resource use), however, have never been assessed at a pan‐European scale. We used meta‐analysis to review 49 published papers containing 120 individual comparisons of species richness between unmanaged and managed forests throughout Europe. We explored the response of different taxonomic groups and the variability of their response with respect to time since abandonment and intensity of forest management. Species richness was slightly higher in unmanaged than in managed forests. Species dependent on forest cover continuity, deadwood, and large trees (bryophytes, lichens, fungi, saproxylic beetles) and carabids were negatively affected by forest management. In contrast, vascular plant species were favored. The response for birds was heterogeneous and probably depended more on factors such as landscape patterns. The global difference in species richness between unmanaged and managed forests increased with time since abandonment and indicated a gradual recovery of biodiversity. Clearcut forests in which the composition of tree species changed had the strongest effect on species richness, but the effects of different types of management on taxa could not be assessed in a robust way because of low numbers of replications in the management‐intensity classes. Our results show that some taxa are more affected by forestry than others, but there is a need for research into poorly studied species groups in Europe and in particular locations. Our meta‐analysis supports the need for a coordinated European research network to study and monitor the biodiversity of different taxa in managed and unmanaged forests.     

广州市城市森林的空间特征与发展研究

应用城市林业的基本理论和ＧＩＳ技术，广州市城区森林的空间分布以两山（白云山、越秀山）两河（珠江、流溪河）为核心，辅之公共绿地和道路绿化，形成多功能、多类型的网络式结构。近郊森林建设好风暴旅游林以及环绕卫星城镇和重点工业镇的生态公益林。远郊森林保障了“菜蓝子”工程，促进森林旅游及其相关产业的发展。     

北方城市干涸河流生态环境治理途径

以滹沱河石家庄市区段为例,针对目前我国北方城市干涸河流治理和改造存在的问题,提出"以绿代水"的生态恢复与重建模式。在对河流进行生态输水、水资源合理管理与调度的同时,选择适宜的研究尺度,恢复流域内自然植被,实现河道中心区草本滞洪补潜、缓冲区灌木束水导流、杨柳护堤造岸、过渡区林果防风固沙的"绿色滹沱",为北方城市干涸河流的生态环境治理提出新的理念和途径。     

Characterization of soil erosion and its implication to forest management

Forests have traditionally been managed to maximize timber production or economic profit, completely neglecting other forest values. Nowadays, however, forests are being managed for multiple uses. The basic requirement of multiple use forestry is to identify and quantify forest values and to determine management objectives. The priorities of management objectives, however, must be decided. In this study, a model predicting the soil loss for multi objective forest management was developed. The model was based on data from remeasurement of permanent sample plots. The data were gathered from 132 sample plots. Approximately 80% of the observations were used for model development and 20% for validation. The model was designed for even aged and uneven aged forests, as well as for forests with mixed and pure species composition. The explicatory variables in the model were mean diameter and number of trees. All parameter estimates were found highly significant (p < 0.001) in predicting soil loss. The model fit and validation tests were fairly good. The soil loss model presented in this paper was considered to have an appropriate level of reliability. It can be used in the overall multi-objective forest management planning, but, it should be limited to the conditions for which the data were gathered.     

Beyond Kyoto: Forest Management in a Time of Rapid Climate Change

Abstract: Policies to reduce global warming by offering credits for carbon sequestration have neglected the effects of forest management on biodiversity. I review properties of forest ecosystems and management options for enhancing the resistance and resilience of forests to climate change. Although forests, as a class, have proved resilient to past changes in climate, today's fragmented and degraded forests are more vulnerable. Adaptation of species to climate change can occur through phenotypic plasticity, evolution, or migration to suitable sites, with the latter probably the most common response in the past. Among the land-use and management practices likely to maintain forest biodiversity and ecological functions during climate change are (1) representing forest types across environmental gradients in reserves; (2) protecting climatic refugia at multiple scales; (3) protecting primary forests; (4) avoiding fragmentation and providing connectivity, especially parallel to climatic gradients; (5) providing buffer zones for adjustment of reserve boundaries; (6) practicing low-intensity forestry and preventing conversion of natural forests to plantations; ( 7) maintaining natural fire regimes; (8) maintaining diverse gene pools; and (9) identifying and protecting functional groups and keystone species. Good forest management in a time of rapidly changing climate differs little from good forest management under more static conditions, but there is increased emphasis on protecting climatic refugia and providing connectivity.     

Current situation and development of Chinese urban forestry

This paper introduces Chinese urban forestry research in terms of the concept, forest types, ecosystem services, spatial structure, planning and construction, assessment and management. Modern Chinese urban forest had a close relationship with traditional landscape architecture. Urban forest services had been quantified in some case cities, and determined by urban forest spatial patterns and internal structures. Based on landscape ecology and urban planning, urban forest spatial patterns have been analysed and planned rationally in some cities. However, studies on urban forestry generally lack long-term, continuous and systemic observations, as well as in-depth research on ecological processes and mechanisms. The development trends in urban forestry in China might include extensive application of '3S' technology, research on the relationship between urban forest landscape spatial patterns and their ecological effects, economic assessment, ecological and economic benefits and studies on the negative effects of pollutants.     

Impact of Forestry Practices on Fitness Correlates and Population Productivity in an Open-Nesting Bird Species

Abstract:  In the boreal forests of Fennoscandia, over 99% of forest area has been altered by forestry practices, which has created forest with age structures and stand characteristics that differ from primary forest stands. Although many researchers have investigated how forestry affects species abundance, few have assessed how forestry practices affect fitness correlates of species living in altered habitats, and this has negatively affected management efforts. We experimentally addressed the effect of standard forestry practices on fitness correlates of an open-nesting, long-lived bird species typical to boreal forests of Eurasia, the Siberian Jay ( Perisoreus infaustus ). We used a before-after comparison of reproductive data on the level of territories and found that standard forestry practices had a strong negative effect on the breeding success of jays. Both partial thinning of territories and partial clearcutting of territories reduced future breeding success by a factor of 0.35. Forestry practices reduced territory occupancy. Thus, over the 15 years of the study, productivity of the affected population declined over 50% as a result of territory abandonment and reduced breeding success. Results of previous studies on Siberian Jays suggest that the strong effect of forest thinning on fitness is explained by the fact that most common predators of nests and adults are visually oriented and thus thinning makes prey and nests more visible to predators. The consequences of thinning we observed are likely to apply to a wide range of species that rely on understory to provide visual protection from predators. Thus, our results are important for the development of effective conservation management protocols and for the refinement of thinning practices.     

Managing mangroves in Bangladesh: A strategy analysis

Bangladesh, favoured by a tropical climate, houses the world’s largest stretch of mangroves forests (Sundarbans Reserved Forest) and plantations. Around half of the forests of the country occur in the coastal zone. People extract various goods and services from the mangroves. Nevertheless the mangrove forests are depleting. Although the extent of the Sundarbans forest has not changed much, its decline is of a qualitative nature. Mangrove plantations are increasing in area but they are losing growing stock. To arrest this, Bangladesh has adopted several strategies. The ‘Sustainable Ecosystem Management’ strategy has now been adopted instead of the ‘Sustained Yield Principle’. Biodiversity conservation and enhancement has been taken as a key management goal. A zoning system is being developed for both production and protection purposes. The government facilitates alternative income for the local people by generating activities for the communities which are dependent on the forest. Different non-governmental organizations collaborate with the government in reducing the local people’s dependence on the forest. Coastal plantations are erected to protect people from cyclones and to make the land more suitable for habitation. Through this greening of the coastal belt tree plantation is encouraged in coastal villages. Coastal embankments are being planted and leased to poor settlers in exchange for routine maintenance of the embankments. Plantations on newly accreted mud flats help in stabilizing the land, which can later on be settled by victims of erosion elsewhere. These adopted management measures do not only contribute to forestry resource management but also to the social, environmental and economic wellbeing of the coastal communities. These efforts are at present being integrated into an Integrated Coastal Zone Management (ICZM) project.