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31.
Protected areas (PAs) are key elements for biodiversity conservation and ecosystem services. Brazil has the largest PA system in the world, covering approximately 220 million ha. This system expanded rapidly in the mid‐1990s to the mid‐2000s. Recent events in Brazil, however, have led to an increase in PA downgrading, downsizing, and degazettement (PADDD). Does this reflect a shift in the country's PA policy? We analyzed the occurrence, frequency, magnitude, type, spatial distribution, and causes of changes in PA boundaries and categories in Brazil. We identified 93 PADDD events from 1981 to 2012. Such events increased in frequency since 2008 and were ascribed primarily to generation and transmission of electricity in Amazonia. In Brazilian parks and reserves, 7.3 million ha were affected by PADDD events, and of these, 5.2 million ha were affected by downsizing or degazetting. Moreover, projects being considered by the Federal Congress may degazette 2.1 million ha of PA in Amazonia alone. Relaxing the protection status of existing PAs is proving to be politically easy in Brazil, and the recent increase in frequency and extension of PADDD reflects a change in governmental policy. By taking advantage of chronic deficiencies in financial and personnel resources and surveillance, disputes over land tenure, and the slowness of the Brazilian justice, government agencies have been implementing PADDD without consultation of civil society. If parks and reserves are to maintain their integrity, there will need to be investments in Brazilian PAs and a better understanding of the benefits PAs provide. Degradación, Reajuste, Eliminacióm de las Listas y Reclasificación de Áreas Protegidas en Brasil 相似文献
32.
我国经济高速发展的同时,出现了矿产资源大量消耗和环境严重污染的问题。许多学者认为是矿产资源国家所有权惹的祸,极力倡导所有权改制。从理性的角度出发分析,出现这种现象并不是国家所有权惹的祸,而是国家所有权的管理体制不再适应今天市场化的要求,应从管理体制和竞争方面来加强矿产资源的管理。 相似文献
33.
34.
A method for evaluating areas for national park status 总被引:1,自引:0,他引:1
Sümer Gülez 《Environmental management》1992,16(6):811-818
A procedure for evaluating different areas as national parks based on a scoring system is proposed. A National Park Evaluation
Form (NPEF) evaluating natural, cultural, and recreational resources in accordance with international criteria for national
parks is presented. The evaluation points given to an area indicate the possibility of the area becoming a national park.
In this method, subjectivity and bias have been minimized by a special application of the Delphi technique. The method outlined
here could help in the efforts of selecting and establishing national parks in many countries. 相似文献
35.
36.
Ben A. Minteer Elizabeth A. Corley 《Journal of Agricultural and Environmental Ethics》2007,20(4):307-333
Few disputes in the annals of US environmentalism enjoy the pedigree of the conservation-preservation debate. Yet, although
many scholars have written extensively on the meaning and history of conservation and preservation in American environmental
thought and practice, the resonance of these concepts outside the academic literature has not been sufficiently examined.
Given the significance of the ideals of conservation and preservation in the justification of environmental policy and management,
however, we believe that a more detailed analysis of the real-world use and understanding of these ideas is needed. In this
paper, we describe the results of a qualitative, semantic study of the concepts of conservation and preservation undertaken
in the context of the Chattahoochee National Forest (CNF), located in northern Georgia (USA). Thirty in-depth interviews were
conducted with scientists and north Georgia residents either interested or involved in the future management of the forest.
Respondents were asked to define conservation and preservation in their own words and to indicate which approach they felt
was more appropriate for the management of the CNF. Qualitative content analysis was used to elicit a set of recurring themes
for each foundational concept. Taken together, these themes help to flesh out the meaning of conservation and preservation
for citizens and scientists today, and illustrate the evolving nature of two of the more significant and venerable ideas animating
US environmental policy and management. 相似文献
37.
Patrick C. Mann John L. Mikesell 《Journal of the American Water Resources Association》1976,12(5):995-1004
ABSTRACT: Two types of organizational systems provide most of the water service in the United States. The investor-owned firm operates on a profit basis generally subject to state commission regulation. The government-owned firm is generally confronted by local control. The comparative efficiency of private versus government firm provision of water services is essentially an empirical issue. Unit costs and other operating statistics are examined for water firms of each ownership form. The analysis shows that private firms tend to have higher operation costs than do government firms, possibly attributable to wage-salary differentials. The analysis also indicates that capital investment in large government firms may result in diseconomies. The analysis creates serious doubt as to whether efficient provision of water services can be better facilitated by large mergers of either ownership form. 相似文献
38.
William E. Sharpe 《Journal of the American Water Resources Association》1978,14(5):1080-1087
ABSTRACT: The municipal water conservation options available to meet the goals of a national water conservation policy are evaluated. Water conservation with water conservation devices is shown to offer many significant advantages over education and pricing and metering as a method of accomplishing water conservation goals. Current constraints on the use of water conservation devices are outlined, and their elimination is suggested if the nation's water conservation goals are to be met. 相似文献
39.
生态足迹是分析和评价国家或地区可持续发展的重要指标。为更加准确地核算小尺度生态足迹,修正了传统生态足迹模型中的均衡因子与产量因子,运用"国家公顷"生态足迹模型,对福建省2012年的生态足迹进行计算。结果表明,福建省2012年的人均生态足迹为1.155372nhm2,人均生态赤字为0.806598nhm2。福建省的人口消费需求超过了自然生态系统的承载能力,可持续发展状况不容乐观。 相似文献
40.
文章运用相关性分析法、主成分分析法探究国庆假日济南城区大气环境质量特征及其影响因素.结果表明:PM2.5、PM10、CO 是国庆期间的主要污染物,小时浓度的峰值出现在9 时和23 时,谷值出现在14 时;PM2.5、PM10是首要污染物,日均浓度(除去10月6日)均超过国家二级标准,10月1日PM2.5浓度上升33.6%,PM10上升34%,10月2日和4日出现浓度"双峰",3日和6日出现浓度"双谷",6日浓度值降至国庆最低,10月7日颗粒物浓度迅速回升;节假日期间,合理安排旅游行程,有利于缓解城市环境压力,促进城市可持续发展. 相似文献