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91.
Guanabara Bay is a 384-km2 coastal bay with 70% of the population of the metropolitan area of Rio de Janeiro located within its drainage basin. The water quality of the Bay is impacted by domestic and industrial runoff, of which only 15% has been adequately treated. However, based on a 14-year monitoring program, the water quality for most of Guanabara Bay remains acceptable because of intense tidal flushing, and we failed to find a worsening of conditions during the 14-year study. The inner shallow regions of the Bay, the western and northwestern parts, receive most of the drainage from metropolitan Rio de Janeiro. It is here that the water quality is alarmingly poor, characterized by hypertrophic conditions and occasional hypoxic events. Fecal coliform counts in these inner reaches of the Bay are 4–100 times higher than the maximum acceptable count for recreational waters. Hypertrophic conditions prevail in Guanabara Bay, which is characterized by low dissolved oxygen, high biochemical oxygen demand, peaks in fecal coliform, and extremely high chlorophyll-a concentrations, which reflect high quantities of nutrients entering the system. These anthropogenic pressures are a threat to planktonic and benthic communities and are reminiscent of San Francisco Bay 30 years ago. The Guanabara Bay water quality could be returned to pre-1950 conditions, but it would require sufficient political will and economic investment to ensure that at least 80–90% of the domestic and industrial sewage were treated adequately. Electronic Publication  相似文献   
92.
The term hot cave is used to describe some subterranean chambers in the Neotropics that are characterized by constantly high ambient temperatures generated by the body heat of high densities of certain bat species. Many of these species have limited geographic ranges, and some occur only in the hot‐cave environment. In addition to the bats, the stable microclimate and abundant bat guano provides refuge and food for a high diversity of invertebrates. Hot caves have so far been described in the Caribbean and in a few isolated locations from Mexico to Brazil, although there is some evidence that similar caves may be present throughout the tropics. The existing literature suggests these poorly known ecosystems, with their unique combination of geomorphology and bat‐generated microclimate, are particularly sensitive to disturbance and face multiple threats from urbanization, agricultural development, mining, and tourism. Diversidad No Explorada y Potencial de Conservación de Cuevas Neotropicales Calientes  相似文献   
93.
This paper analyses shrimp caught from the wild and farmed shrimp in Brazil, focusing on production, amounts exported and earnings, with comparisons drawn to all of South America and the world in general. We show that wild caught shrimp still comprises the majority of what is produced and exported in Brazil, although aquaculture has been taking a relevant role in the internal and external scenario, reaching similar levels of extraction in recent years. Despite some fluctuations in the amount of extracted shrimp, Brazil increased its production from 15,000 tons in 1950 to 80,000 in 2004. The money earned with shrimp product exportation, which includes farmed shrimp as well, followed a similar tendency. Shrimp aquaculture began late in Brazil, in 1974, and grew slowly until 1995, initiating an accelerated growing process; current estimates assume 50,000 people are employed in this activity, producing about 76,000 tons of shrimp every year. Although still incipient in relation to the world shrimp farmed production, Brazil has been assuming a relevant role in South America, yielding 44% of its total production, in 2004. Despite the importance of shrimp to the country, no studies have been conducted to explore the interrelations between the environmental and social consequences of such unplanned aquaculture growth or uncontrolled wild shrimp fishing. Based on previous observations, conflicts exist between different fishing scales. However, the consequences of shrimp farming on society (displacement from their lands, changes in the life quality, etc.) have not yet been explored. Both activities, shrimp exploitation and aquaculture, deserve better control and structure toward sustainable shrimp fishing and farming. Readers should send their comments on this paper to: BhaskarNath@aol.com within 3 months of publication of this issue.  相似文献   
94.
The socio‐economic fabric of single‐company mining towns needs to be carefully considered by both Government and companies in sustainability policymaking. Policy design and effectiveness in such towns are significantly impacted by the city's economic dependence on a single company. This paper explores the perceived effectiveness of government and voluntary private sector mining policies for pursuing sustainability in the historic mining town of Itabira, Brazil over a period of 20 years. Itabira serves as a worthwhile case study because it allows for an in‐depth and longitudinal analysis that can reveal valuable lessons to policymakers of different sectors and jurisdictions located elsewhere. Based on extensive face‐to‐face interviews and literature reviews, study results indicate that changes to the state environmental licensing policies in the 1990s led to significant socio‐environmental improvements in the area. The globalization of the mining company also contributed to an increase in the quantity and quality of voluntary industry policies. Recent technological improvements in the beneficiation processes of the mining company promises to extend the life of the mine to 2050. Although there are significant incremental socio‐environmental policies and programmes, sustainability remains an elusive vision in Itabira, with no clear objectives or monitoring and accountability mechanisms. The paper concludes by recommending a more formal integrated policymaking framework.  相似文献   
95.
The policy intervention to enforce property rights and control deforestation frontiers is often undermined in the Brazilian Amazon, and this intervention problem is considered to be stemming from weak frontier governance. However, little has been understood how this governance can be strengthened in the context of social change. Drawing on a literature review of the Amazon development and sociological studies of space, this article argues that frontier governance is characterised by the co-generation of two territorial processes: the official settlement implementation (physical spacing) and the spontaneous settlers' shaping of the vernacular community (production of place). The co-generation process opens new deliberative space where both state and non-state actors claim authority over the intervention. Therefore, strengthening frontier governance involves empowering this emerging authority to be able to promote public engagement with sustainable development on the frontier. The article uses the regional history and ethnographic material collected in the southeast of Pará to illustrate the discussion.  相似文献   
96.
Brazil's Tucuruí Dam provides valuable lessons for improving decision-making on major public works in Amazonia and elsewhere. Together with social impacts, which were reviewed in a companion paper, the project's environmental costs are substantial. Monetary costs include costs of construction and maintenance and opportunity costs of natural resources (such as timber) and of the money invested by the Brazilian government. Environmental costs include forest loss, leading to both loss of natural ecosystems and to greenhouse gas emissions. Aquatic ecosystems are heavily affected by the blockage of fish migration and by creation of anoxic environments. Decay of vegetation left in the reservoir creates anoxic water that can corrode turbines, as well as producing methane and providing conditions for methylation of mercury. Defoliants were considered for removing forest in the submergence area but plans were aborted amid a public controversy. Another controversy surrounded impacts of defoliants used to prevent regrowth along the transmission line. Mitigation measures included archaeological and faunal salvage and creation of a “gene bank” on an island in the reservoir. Decision-making in the case of Tucuruí was virtually uninfluenced by environmental studies, which were done concurrently with construction. The dam predates Brazil's 1986 requirement of an Environmental Impact Assessment. Despite limitations, research results provide valuable information for future dams. Extensive public-relations use of the research effort and of mitigation measures such as faunal salvage were evident. Decision-making was closely linked to the influence of construction firms, the military, and foreign financial interests in both the construction project and the use of the resulting electrical power (most of which is used for aluminum smelting). Social and environmental costs received virtually no consideration when decisions were made, an outcome facilitated by a curtain of secrecy surrounding many aspects of the project. Despite improvements in Brazil's system of environmental impact assessment since the Tucuruí reservoir was filled in 1984, many essential features of the decision-making system remain unchanged.  相似文献   
97.
This article describes the co‐management approach in situations of open access to and of increasing pressure on resources, using a mangrove coastal zone in North Brazil as an example. Co‐management clearly has the potential to turn nonviable, de facto open access to mangroves into effective common property management. Alliances of different political and ideological groups have been formed under the RESEX (reservas extrativistas — natural resource user reserve) model of coastal co‐management. Local economic interests have been mobilized as client constituencies. The RESEX system of co‐management assigns additional duties to both co‐managing parties, i.e., the state administration and the local users, in exchange for new rights. The authors argue that local support for the RESEX model has been gained on partially distorted premises. As the public authority passes on responsibility for management to local users under the RESEX model, this entails a number of duties for the local users. Thus local users assume the duty to implement and monitor resource management; they also appear to gain the right to take local decisions, such as excluding outsiders from resource access, and designing local resource management rules. However, as this article shows with two examples, some important new rights for local users under the RESEX co‐management concept are contrary to environmental legislation in force. This conflict is at present unresolved. It is argued that increased transparency about their precise rights for local resource co‐managers will considerably improve the prospects of coastal co‐management in Brazil.  相似文献   
98.
This article discusses the development of corporate social responsibility (CSR) in Brazil from the perspective of the Ethos Institute of Business and Social Responsibility. The Institute is a not‐for‐profit, non‐governmental organization, that has played a leading role in the Brazilian CSR effort. In Brazil, CSR initiatives have a long tradition of philanthropy, a consequence of the country's great social inequalities. The increased attention to corporate social responsibility has paralleled growing concern about sustainable development and the intensifying activities of pressure groups (consumers, customers, investors, NGOs, labour unions, the media, among others) that have been increasing since the 1990s as natural resources are progressively becoming exhausted, social tensions rising and environmental conditions deteriorating worldwide. This article identifies problems and obstacles to the growth of corporate social responsibility in Brazil, as well as advances and alternatives for CSR and towards creating conditions for the country to be internationally competitive and sustainable in the financial, social and environmental areas.  相似文献   
99.
This article presents a case study of a project which provides photovoltaic-based rural electrification in the state of Alagoas in northeastern Brazil. The project, the Luz do Sol Programme (LdS), was initiated in mid-1996 by the Golden Genesis Company (Golden) and the Fundação Teotônio Vilela (FTV). The article emphasizes some noteworthy characteristics of the project: the partnership between US commercial and Brazilian philanthropic interests; the financial aspect, a dedicated line of credit requiring only the equipment itself as security; and the local ownership and management of system operations, collections, and routine maintenance.
In 1996, the Golden Genesis Company had developed a central battery charging system to bring the price of electrification within the range of the rural poor; it financed the US content of the systems, with the Bank of the Northeast of Brazil (BN) financing the Brazilian content. The article traces the long and arduous path to establish the programme, including both bureaucratic and technical challenges. These difficulties brought the project to an impasse in August of 1998, and Golden withdrew. FTV then re-negotiated the agreement with BN, changing the technical approach to individual solar home systems. This improved the situation, and the project has since enjoyed 100% loan repayment rates from the entrepreneurs. In June 1999, BP/Solarex became FTV's new commercial partner. The project currently shows promise of becoming the commercially viable programme originally envisaged by Golden, with commercial and technical decision-making at the local level.  相似文献   
100.
滇东北山原区是云南省的区域性贫困区.该区以山地为主.自然条件垂直差异大、土地资源质量较差、管理上存在问题多.本文以会泽县为例,对该区土地资源的持续利用进行了探讨.  相似文献   
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