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31.
To reduce future loss of biodiversity and to allocate conservation funds effectively, the major drivers behind large‐scale extinction processes must be identified. A promising approach is to link the red‐list status of species and specific traits that connect species of functionally important taxa or guilds to resources they rely on. Such traits can be used to detect the influence of anthropogenic ecosystem changes and conservation efforts on species, which allows for practical recommendations for conservation. We modeled the German Red List categories as an ordinal index of extinction risk of 1025 saproxylic beetles with a proportional‐odds linear mixed‐effects model for ordered categorical responses. In this model, we estimated fixed effects for intrinsic traits characterizing species biology, required resources, and distribution with phylogenetically correlated random intercepts. The model also allowed predictions of extinction risk for species with no red‐list category. Our model revealed a higher extinction risk for lowland and large species as well as for species that rely on wood of large diameter, broad‐leaved trees, or open canopy. These results mirror well the ecological degradation of European forests over the last centuries caused by modern forestry, that is the conversion of natural broad‐leaved forests to dense conifer‐dominated forests and the loss of old growth and dead wood. Therefore, conservation activities aimed at saproxylic beetles in all types of forests in Central and Western Europe should focus on lowlands, and habitat management of forest stands should aim at increasing the amount of dead wood of large diameter, dead wood of broad‐leaved trees, and dead wood in sunny areas.  相似文献   
32.
太行山是我国山地植被破坏历史最长、生态环境严重恶化的山地生态系统,“七五”期间国家将绿化太行山列入重点攻关项目。从1986年开始,作者根据生态工程原理提出:环境辨识工程、种群引进选择工程、种群匹配工程、水土富集工程、时间节律工程和食物链工程为主的立体林业工程新思想,并在湘山小流域建起实施模式。经四年的工作,已取得较大进展。  相似文献   
33.
三水市农业生态系统经济能值投入产出分析   总被引:13,自引:1,他引:13  
进行生态学与经济学系统分析方法的交叉探索,将能值这一全新的生态经济度量尺度引入经济学投入产出分析表,对广东省珠江三角洲三水市农业生态系统经济能值的直接消耗系统和完全消耗系统分析,弥补经济学分析中自然环境投入价值缺失的同时,为复合系统能值分析中各系统间互作分析的量化评价探索了新的途径。分析结果表明:三水市农业生态系统中种植业、渔业、畜牧业和林业之间存在经济能值的依存关系,有着直接的相互作用。种植业、渔业和畜牧业子系统间的经济能值交流网络较为发达。在种植业、渔业、畜牧业和林业中,渔业对种植业的完全消耗系数最大,达到3.461×10-2,畜牧业对种植业的完全消耗系数也最大,达到了8.423×10-2;种植业对渔业的完全消耗系数最大,达到了7.685×10-2。林业与种植业、渔业、畜牧业互相的完全消耗系数都比较小,林业和其它三个子系统的经济能值交流较弱。种植业子系统是整个三水市农业生态系统的基础,渔业和畜牧业在种植业的基础上发展,对物质和能量的再利用起了重要作用。林业子系统是三水市农业生态系统内部物质能量交流网络的薄弱环节。三水市农业生态系统的内部结构有待进一步调整,以加强各子系统间的互作,提高物质与能量的使用效率。  相似文献   
34.
针对森工林区特种设备安全监察工作面临的突出问题,提出了建立行之有效的管理体制、切实可行的执法手段等对策措施。  相似文献   
35.
从基层林业企业安全教育管理现状出发,分析了当前安全教育管理存在的问题,结合新形势下林业企业实际,探索创新安全生产管理路径与措施。  相似文献   
36.
阐述了近几年来全国南方集体林区重点林业县的福建省尤溪县在发展林业产业、调整林业产业结构、推进林业产业化进程、生产安全中所取的成效,以及存在的问题,并以此提出今后集体林区林业产业发展的指导性、实用性的对策与建议。  相似文献   
37.
介绍了智慧林业的概念、基本特征及形成背景、新观念,分析了数字林业、智慧林业与泛在林业的关系,阐述了中国及智慧林业发展战略,建议深入研究智慧林业定义、内涵、外延、特征、观点、问题及对策,以便形成一门崭新的科学——智慧林业科学.  相似文献   
38.
China has the fifth largest forest area in the world and any change in China's forestry development will have inevitable impacts on global ecological sustainability. China has undergone excessive logging of natural forests and also made tremendous efforts in afforestation during the past half century. China's forestry is now going through a variety of transitions and several forestry programs have been implemented to drive forestry transitions. The goal of these actions is to protect ecological services of forests and sustain China's forestry development. These forestry programs are spatially sophisticated and cannot be successfully implemented without accurate and transparent forest/forestry information. A variety of digital technologies, including forest modeling, remote sensing, geographic information systems, global positioning systems, and visualization, have been applied in handling diverse information in China's forestry. Digital forestry is not just a theoretical concept in China. Our digital forestry experience in northeast China suggests that digital technology is both usable and useful in China's forestry development. Digital technology is playing an important interactive role in China's top-down forestry administration system. The analog-to-digital transition in technology is expected to lead to the success of forestry programs and forestry transitions in China.  相似文献   
39.
This paper studies the emergence of one particular ‘new’ environmental policy instrument: disclosure of emission and pollution data. Disclosure is part of a relatively new sub‐set of regulatory measures, based on monitoring, transparency, citizen‐empowerment and accountability. It originated in the United States but has recently attracted international attention. The attractiveness of disclosure is obvious; it promises environmental improvement combined with strengthened environmental democracy and community empowerment. By analysing the experiences in the US, and the developments in the Netherlands, this paper seeks to assess the functioning and effectiveness of disclosure. The available empirical evidence suggests that disclosure has a positive impact on the environmental performance of industrial facilities as well as a democratising effect. It is argued that Dutch policy makers wrongfully assume that disclosure cannot work in the Netherlands. The consequence is that citizens are provided with little specific information that cannot be used to put pressure on polluters.  相似文献   
40.
International forestry governance is an integral part of the global policy debates on how to prevent deforestation, illicit extraction, and unsustainable timber practices. Africa is an important producer of timber, yet the region is beset by a lack of capacity and other governance challenges in the management of its forestry sector. We employ a network governance analysis to examine the extent to which the evolution and operation of the Forest Stewardship Council (FSC) and la Commission des Forêts d'Afrique Centrale (COMIFAC) have addressed governance challenges. We assess the strengths and weaknesses of these two leading examples of international forestry governance by introducing recent evidence and insights from Africa. We conclude with a policy‐relevant discussion of how the FSC and COMIFAC might enhance authority, legitimacy, and effectiveness and improve forestry governance in Africa and other parts of the world.  相似文献   
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