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771.
Bogdan Stefanović Dušan Stojnić Milorad Danilović 《Journal of Environmental Planning and Management》2016,59(5):911-926
This paper presents a multi-criteria selection of the best forest road network with the aim of achieving effective preventive and timely repressive protection against forest fires. The research was carried out in national park (NP) “Tara” at a site which is under constant threat of fire. Four variants of the forest road network were designed and analyzed against seven criteria, and the best variant was selected using entropy weight coefficients (EWC) method. The importance of these seven criteria was studied by the management of the NP “Tara.” The greatest importance was given to the criteria relating to the cost of construction and maintenance of permanent and temporary roads (47% of the total value of all criteria). The EWC method did not select the variant based on the lowest costs of construction and maintenance as the best option, but the variant whose location was the most suitable for effective defense against forest fires. 相似文献
772.
773.
Out of the wilderness? Achieving sustainable development within Scottish national parks 总被引:1,自引:0,他引:1
The introduction of national parks to Scotland represents a significant shift in the evolution of protected area management within the UK. Although the National Parks (Scotland) Act 2000 adopts the established national park aims of conservation and recreation, provisions are also made for advancing notions of sustainable development. This paper provides an assessment of the degree to which the Scottish national park model is likely to enable the realisation of multiple national park objectives. Five key areas are considered for analysis. These relate to management aims, institutional arrangements, implementation, democratic accountability and funding. The evaluation reveals that whilst management provisions have been established in accordance with international sustainable development guidelines, a number of concerns relating to operational processes remain. 相似文献
774.
Attempts to minimize the effects of human–wildlife conflict (HWC) on conservation goals require an understanding of the mechanisms by which such conflicts are caused and sustained. This necessitates looking beyond the natural sciences to the human dimensions of wildlife management. Public dissemination of information regarding HWC occurs largely through the mass media. We conducted a content analysis of print media articles on human–leopard conflict in Mumbai, India. We sought to understand the framing of HWC and the changes in media coverage over a 10‐year period (2001–2011) during which a large number of attacks on people prior to 2005 were followed by a program of trapping and relocation. After 2005, when there was a decrease in the level of conflict, the tone of English‐language media reports changed. The perpetrator framing was over 5 times more likely before 2005, whereas a neutral framing was twice as likely after 2005. English‐language and non‐English‐language print media differed significantly in their framing of HWC and in the kinds of solutions advocated. Our results also suggest the print mass media in Mumbai could be an influential conduit for content that diminishes HWC. These media outlets seem attentive to human–leopard conflict, capable of correcting erroneous perceptions and facilitating mitigation and effective management. We believe better contact and mutual understanding between conservation professionals and the mass media could be an important component of managing HWC. We further suggest that in such interactions conservation professionals need to be aware of cultural and linguistic differences in reporting within the country. Entendiendo el Papel de las Representaciones del Conflicto Humano–Leopardo en Mumbai A Través del Análisis de Contenido de Medios 相似文献
775.
植物自然丰度的稳定性N同位素(δ15N)在植物N吸收和N转运过程中会发生变化,但植物叶片在凋落之前的N素的再吸收如何影响δ15N变化还不清楚.本研究以凉水地区的14个常见树种和宝天曼地区的16个常见树种为研究对象,测定各树种新鲜叶和凋落叶及其对应土壤中的C、N质量分数和δ15N值.结果表明,凉水树种新鲜叶N质量分数和δ15N值显著高于宝天曼树种,这与凉水土壤的N质量分数和δ15N值都高于宝天曼土壤相对应.此外,凉水树种叶片N吸收率(47%)与宝天曼树种(40%)无显著差异.宝天曼树种凋落叶中的δ15N显著高于新鲜叶中的δ15N值,即叶片N再吸收过程中存在N同位素的分馏效应,而凉水树种凋落叶与新鲜叶中的δ15N无显著性差异.本研究首次报道在植物叶片N再吸收过程中存在显著的同位素分馏效应,而且分馏效应的程度与N再吸收率显著负相关.此外,植物叶片N再吸收过程中是否存在同位素分馏效应可能取决于叶片的N再吸收率;乔木新鲜叶片N质量分数和δ15N值在地区间的差异可能取决于土壤N质量分数和δ15N值的地区差异;叶片N再吸收率可能与N在叶片中的存在形态有关,而与土壤N质量分数不相关. 相似文献
776.
猫儿山自然保护区森林群落垂直格局与主导因素分析 总被引:2,自引:0,他引:2
陆地生态系统中海拔高度的变化会导致植物群落的垂直性分布,这是形成植物多样性的一个重要性原因。了解和分析不同区域植物群落的垂直性分布规律和生物多样性形成机制对保护森林生物多样性具有重要意义。本文通过对猫儿山自然保护区不同海拔高度森林植物群落和环境因子的调查,运用双向指示种分析(Two-way Indicator-Species Analysis)和典范对应分析(Canonical Correspondence Analysis),对不同海拔高度的群落进行划分,对决定植物群落分布的主导环境因子进行分析,结果表明:(1)猫儿自然保护区森林群落可以分为7个群落类型,其代表树种分别是罗浮栲Castanopsis fabri、栲树Castanopsis fargeisii、银木荷Schima argentea、铁椎栲Castanopsis lamontii、南方铁杉Tsuga chinensis、长苞铁杉Tsuga longibracterata、马尾松Pinus massoniana;(2)在中亚热带,海拔对山地植物群落形成起决定性作用;(3)土壤是仅次于海拔的重要环境因子,其中土类和土层厚度对森林群落的影响较大。在中亚热带森林生态保护和恢复过程中,按照不同海拔高度的植物群落特征选择种植合适树种,按照当地土壤条件选择适当的生态保护和恢复措施能加快生态恢复的进程,提高生态保护的效益。 相似文献
777.
A multi-scaled model for biodiversity conservation in forests was introduced in Sweden 30 years ago, which makes it a pioneer
example of an integrated ecosystem approach. Trees are set aside for biodiversity purposes at multiple scale levels varying
from individual trees to areas of thousands of hectares, with landowner responsibility at the lowest level and with increasing
state involvement at higher levels. Ecological theory supports the multi-scaled approach, and retention efforts at every harvest
occasion stimulate landowners’ interest in conservation. We argue that the model has large advantages but that in a future
with intensified forestry and global warming, development based on more progressive thinking is necessary to maintain and
increase biodiversity. Suggestions for the future include joint planning for several forest owners, consideration of cost-effectiveness,
accepting opportunistic work models, adjusting retention levels to stand and landscape composition, introduction of temporary
reserves, creation of “receiver habitats” for species escaping climate change, and protection of young forests. 相似文献
778.
祁连山自然保护区生态承载力分析与评价 总被引:7,自引:0,他引:7
以层次分析法和模糊模式识别为基础,建立生态承载力综合评价模型,重点分析祁连山自然保护区森林、草地和农田3种受人类活动干扰最强烈的生态系统的生态承载力和生态荷载,在此基础上进一步分析整个保护区的总体生态承载力和生态荷载。结果显示,祁连山区域生态系统已经受到人类活动的强烈干扰,生态荷载总体处于严重超载状态。但区域生态系统内部各子系统之间以及生态荷载的空间分布存在差异。其中,森林子系统和草地子系统属于严重超载,农田子系统属于中度超载;在总体生态荷载的空间分布上,西北部地区比东南部地区超载更为严重;就各子系统的生态荷载状况而言,森林子系统和草地子系统的超载程度均表现为东南部地区略低于西北部地区,但农田子系统东南部地区超载程度高于西北部地区。 相似文献
779.
780.
从效益水平、高度水平、转换水平、科技水平四个方面构建了工业结构竞争力的综合评价指标体系,采用熵值法对2000-2007年的黑龙江省工业结构竞争力进行了综合测度.结果表明,影响黑龙江省工业结构竞争力的因素表现为多元化和均衡化,竞争力螺旋上升,以波动性强、子系统变化悬殊为主要特征,科技水平是竞争力得以提高的主要因素.在子系统中,效益和高度子系统具有较为明显的阶段性,转换子系统体现为不连续性,科技子系统则在稳步提高.分析表明,黑龙江省工业结构竟争力存在科技水平不高、结构转换能力不足、高度化水平低、工业经济区域发展不均衡、资源枯竭与工业发展矛盾日益突出等问题,在此基础上简要提出了对策. 相似文献