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1.
In 1985, in response to declining coral reef conditions, local residents and officials established small, no-take marine sanctuaries on Balicasag and Pamilacan Islands through a community-based process. The implementation of marine protected areas (MPAs) on Balicasag and Pamilacan Islands has been a partial success. As a direct result of protection, living hard coral cover has increased by 119% in Balicasag's sanctuary and by 67% in the non-sanctuary during the period 1984 to 1999, but Balicasag's reef is increasingly affected by breakage from anchors from dive boats and Crown-of-thorns starfish infestations. During the same period, living hard coral cover decreased by 20% in Pamilacan's sanctuary and by 45% in the non-sanctuary from 1984 to 1999. The decrease in living hard coral cover in Pamilacan's sanctuary is most likely a result of the 1998 bleaching event, Crown-of-thorn starfish and possible storm damage. Although there was an initial increase in the economically important target fish abundance in the Balicasag sanctuary and non-sanctuary and in the Pamilacan sanctuary during the first two years of implementation in the mid-1980s, there has since been a significant decline. Mean target fish abundance for the Balicasag non-sanctuary at 230 (+/- 65) individuals per 500 m2 is not significantly different from control sites without MPAs on nearby Panglao and Cabilao Islands at 164 (+/- 67) individuals per 500 m2. In general, fish abundance and diversity inside and outside the sanctuaries peaked in 1986, a year after the establishment of the sanctuaries when enforcement was strictest. Therefore, despite considerable success in enforcing regulations associated with these small MPAs at Balicasag and Pamilacan Islands, a trend of declining fish abundance and species richness among economically valuable species immediately outside the no-take areas highlights the limitations of small and isolated MPAs. This study contributes to the growing sentiment that it is not realistic for scattered, small no-take areas to maintain fish abundance and diversity on surrounding reefs when intensive fishing effort immediately adjacent to no-take areas removes most fish that exit these areas. This finding emphasizes the importance of nesting individual MPAs within broader management regimes that lead to overall fishing effort reduction and networking of MPAs. Among other recommendations, the authors advocate for continued support for community-based MPAs, a network of MPAs, reduced fishing effort in areas surrounding the MPAs and other management measures to improve the quality of the coral reef habitats.  相似文献   

2.
Marine water pollution affects many recreational sites around the world. It has impacts not only on recreational activities but also on health risks for those who come into direct contact with the water. Few economic studies have explicitly considered the health risks of bathing in polluted marine waters and none have attempted to separate health benefits from other benefits of marine water quality improvements. This paper uses stated preference techniques to separately evaluate the multiple benefits of improving the quality of marine recreational waters at the Estoril Coast in Portugal. The results indicate that health risk reductions are only a small fraction of the total social benefits of water quality improvements.  相似文献   

3.
Establishing “social licences to operate” with communities has become a significant corporate social responsibility agenda. The complex dynamics of these relationships can compound the impacts for communities when these contracts are not upheld. This article documents reflections from a rapid rural appraisal conducted in the Shire of Ravensthorpe in remote Western Australia after the Ravensthorpe Nickel Operation was “mothballed” 9 months into a projected 25-year lifespan. It captures how communication about the project and its time frames created a sense of consistency, predictability, certainty and trust – enabling social licence. The raising of hope and the emergence of mistrust underpin social, environmental and financial impacts of this event for the local community. Embedded in the theoretical dimensions of social licences, this case study highlights the problematic of social licences that engage with non-contractual stakeholders as partners in “booms” but have no legal responsibility towards them in times of “bust”.  相似文献   

4.
The conference entitled Managing for Biodiversity: Emerging Ideas for the Electric Utility Industry was held in Williamsburg, Virginia, USA, during 19–20 March 1996. This paper provides an overview of the key points, conclusions, and recommendations from both the presentations/papers and the discussions throughout the conference.  相似文献   

5.
Environment Systems and Decisions - The depletion of natural resources as a byproduct of widespread, global economic growth has urged entrepreneurs to think about the environment when starting or...  相似文献   

6.
In public debates, agricultural biotechnology is almost invariably discussed as a potential threat to the environment and to human health. Without downplaying the risks associated with this technology we emphasize that if properly regulated, it can be a forceful tool to solve environmental problems and promote human health. Agricultural biotechnology can reduce environmental problems in at least three ways: it can diminish the need for environmentally damaging agricultural practices such as pesticides, fertilizers, tillage, and irrigation. It can reduce the land area needed for agriculture, thus reducing the CO2 effect of agriculture and improving biodiversity. It can produce energy in a CO2-neutral way (especially if new technologies involving the cultivation of microalgae become successful). Furthermore, agricultural biotechnology can have positive effects on human health by decreasing occupational and dietary exposure to pesticides, improving the nutritional value of food, and producing pharmaceuticals more efficiently. We argue that those who wish to give high priority to environmental goals cannot afford any longer to be mere onlookers while others decide the future directions of agricultural biotechnology.  相似文献   

7.
Chang R  Fu B  Liu G  Liu S 《Environmental management》2011,48(6):1158-1172
Conversion of cropland into perennial vegetation land can increase soil organic carbon (SOC) accumulation, which might be an important mitigation measure to sequester carbon dioxide from the atmosphere. The “Grain for Green” project, one of the most ambitious ecological programmes launched in modern China, aims at transforming the low-yield slope cropland into grassland and woodland. The Loess Plateau in China is the most important target of this project due to its serious soil erosion. The objectives of this study are to answer three questions: (1) what is the rate of the SOC accumulation for this “Grain for Green” project in Loess Plateau? (2) Is there a difference in SOC sequestration among different restoration types, including grassland, shrub and forest? (3) Is the effect of restoration types on SOC accumulation different among northern, middle and southern regions of the Loess Plateau? Based on analysis of the data collected from the literature conducted in the Loess Plateau, we found that SOC increased at a rate of 0.712 TgC/year in the top 20 cm soil layer for 60 years under this project across the entire Loess Plateau. This was a relatively reliable estimation based on current data, although there were some uncertainties. Compared to grassland, forest had a significantly greater effect on SOC accumulation in middle and southern Loess Plateau but had a weaker effect in the northern Loess Plateau. There were no differences found in SOC sequestration between shrub and grassland across the entire Loess Plateau. Grassland had a stronger effect on SOC sequestration in the northern Loess Plateau than in the middle and southern regions. In contrast, forest could increase more SOC in the middle and southern Loess Plateau than in the northern Loess Plateau, whereas shrub had a similar effect on SOC sequestration across the Loess Plateau. Our results suggest that the “Grain for Green” project can significantly increase the SOC storage in Loess Plateau, and it is recommended to expand grassland and shrub areas in the northern Loess Plateau and forest in the middle and southern Loess Plateau to enhance the SOC sequestration in this area.  相似文献   

8.
Sorption of butachlor to various types of common soil components was investigated. Six pure minerals (montmorillonite [Mont], kaolinite [Kaol], Ca homoionic montmorillonite [Ca-Mont] and kaolinite [Ca-Kaol], amorphous hydrated Al and Fe oxides [AHOs-Al, AHOs-Fe]), four soil alkali-extractable pure humic acids (HAs), and the four corresponding HAs originated real unmodified and HO-treated soils were selected as the representative sorbents. Results showed that the HAs played a crucial role, and clay minerals (especially Mont) also showed an important effect in butachlor sorption. The AHOs may likely influence only in a mediator way by enhancing the availability of sorption domains of HAs. By removing 78% (on average) of the total organic carbon (TOC) from the soils with HO, the content ratio of clay to TOC (RCO) increased by an average of 367% and became >60. This change simultaneously decreased the sorption capacity of soils (40%, on average). Considering that the surface sorption domain on clay minerals may be highly exposed and more competitive after the partial removal of soil organic matter (SOM), this reaffirmed the potential contribution from clay minerals. It can thus be inferred that in the real soil where SOM and clay minerals are associated, the coating of clay minerals may have weakened the partition function of SOM or blocked some sorption domain within SOM, resulting in a decreased sorption of butachlor. Therefore, clay minerals, especially 2:1 type expanding minerals, may play a dual function vs. SOM content for the sorption of butachlor in soil.  相似文献   

9.
Stakeholders in plantation forestry are increasingly aware of the importance of the ecosystem services and non-market values associated with forests. In New Zealand, there is significant interest in establishing species other than Pinus radiata D. Don (the dominant plantation species) in the belief that alternative species are better suited to deliver these services. Significant risk is associated with this position as there is little objective data to support these views. To identify which species were likely to be planted to deliver ecosystem services, a survey was distributed to examine stakeholder perceptions. Stakeholders were asked which of 15 tree attributes contributed to the provision of five ecosystem services (amenity value, bioenergy production, carbon capture, the diversity of native habitat, and erosion control/water quality) and to identify which of 22 candidate tree species possessed those attributes. These data were combined to identify the species perceived most suitable for the delivery of each ecosystem service. Sequoia sempervirens (D.Don) Endl. closely matched the stakeholder derived ideotypes associated with all five ecosystem services. Comparisons to data from growth, physiological and ecological studies demonstrated that many of the opinions held by stakeholders were inaccurate, leading to erroneous assumptions regarding the suitability of most candidate species. Stakeholder perceptions substantially influence tree species selection, and plantations established on the basis of inaccurate opinions are unlikely to deliver the desired outcomes. Attitudinal surveys associated with engagement campaigns are essential to improve stakeholder knowledge, advancing the development of fit-for-purpose forest management that provides the required ecosystem services.  相似文献   

10.
11.
Are there threshold numbers for protected forests?   总被引:4,自引:0,他引:4  
Maintenance of forests biodiversity is intimately related on the one hand to the species and community-related ecological needs of flora and fauna living in the forest and on the other hand the disturbance regimes of the specific forest type. Populations of plants and animals need minimum biotopes for their ontogeny; for assuring their survival they depend on a minimum of connected suitable areas. Specific traits of forest types are based upon different disturbance regimes, ranging from small-scale internal processes (e.g. regeneration, growth, senescence, mortality, gap dynamics) generating normal forest cycles (i.e. regular sequences, e.g. regeneration, optimum, decay phases) to potentially chaotic and large-scale, frequently external, disturbances, e.g. fire, landslides, or beetle attacks. Forest protection may meet the needs of these very different demands by varied protected area networks going from small (>100 ha), medium (1000 ha) to large-scale reserves (National Parks, several thousands of ha). According to this triple protection concept not only graduated threshold numbers, but also threshold sizes and threshold areas for forest protection must be defined. To realize this concept the regional and local conditions (forest area, forest cover percentage, forest composition, socio-economic targets) must always be taken in consideration.  相似文献   

12.
Public engagement in local environmental planning and decision-making is often advocated on various grounds, both instrumental and normative. Yet in developed countries in the context of renewable energy infrastructure deployment, place attachment, place identity and place-protective action continue to be implicated in public objection. We set out an interdisciplinary change readiness hypothesis of specifically how local participatory scenario or visioning processes that include climate mitigation measures may support the mobilisation of place attachment for climate mitigation, including renewable energy deployment. We hypothesise that local visioning may support movement towards change readiness by helping to anchor unfamiliar social representations of low carbon energy infrastructure and new patterns of urban form in existing, more positive representations of localities and associated attachments. To this end, seeking ways to modify threat perceptions relating to climate change and renewable energy infrastructure is advocated as a key direction for study.  相似文献   

13.
Tellurium is increasingly used in solar photovoltaics in the form of cadmium–telluride (CdTe) thin films. There are concerns regarding whether tellurium availability could be a constraint on large-scale deployment of CdTe photovoltaics. The present work brings a new perspective to the discussion of tellurium availability by providing the first extant global tellurium cycles constructed with material flow analysis principles. The tellurium cycles, for 1940–2010, present information on the production, fabrication and manufacturing, use, and resource management stages during this period. The results of the analysis show that during 1940–2010 approximately 11 Gg of refined tellurium was produced. This represents about 4.5% of the tellurium that was extracted from the ground during copper mining. Almost 80% of the refined tellurium, 8.5 Gg, was dissipated into end-uses such as metallurgical additives to iron, steel, and nonferrous metals, and thereby lost to potential reuse. As of 2010, the in-use tellurium stock is estimated at 1.1 Gg, which mainly accumulated after 1990s with the increasing tellurium use in electronics, specifically photovoltaic and thermoelectric devices. Because tellurium is a byproduct of copper ores, its supply can be enhanced by more attention to recovery during processing of the copper parent. Tellurium can also, in principle, be recovered from end-of-life electronics; the increasing in-use stock indicates the potential for significant end-of-life recycling in the coming decades.  相似文献   

14.
Estuarine areas worldwide are under intense pressure due to human activities such as upstream dam building. Shorebirds strongly depend on estuarine intertidal flats during migration and wintering periods and so are particularly vulnerable to such impacts, whose magnitude will depend on the availability of alternative feeding habitats. In this study we analyze if man-made saltpans can represent an alternative habitat for wintering and migrating shorebirds in the Guadiana estuary, a wetland that is already experiencing environmental changes due to the building of the Alqueva reservoir, the largest in Western Europe. We compared the use of mudflats and saltpans as feeding areas by several shorebird species before the construction of the dam. A dataset with 26 years of counts data was also analyzed in order to detect any long-term trend in shorebirds abundance. We concluded that saltpans, in particular the fully mechanized, can be used as an alternative habitat by larger species during winter and southward migration, thus playing a major role in minimizing the possible effects of sediment loss due to dam building. In contrast, smaller species were particularly dependent on mudflats to feed. A significant change in population trends, from positive to negative, was detected for two species. Although we still have no evidence that this is directly linked to dam building, this result and documented changes that limit primary productivity justifies the implementation of a long-term monitoring scheme of shorebird populations in this estuary. We also reinforce the need to manage the saltpans as key habitats for shorebirds.  相似文献   

15.
The paper examines alternative roles for planners in planning for sustainable development. First, it outlines the particular context of the task focusing on operational questions, critical issues and sustainable development planning principles. It then explores roles for planners in this context distinguishing broadly among technician, politician and hybrid planners. It evaluates broadly each role's effectiveness and challenges, in particular decision making and political contexts. Finally, it discusses, first, the implications of these roles for planning education and identifies the main groups of skills planning schools should offer. Second, it analyses briefly the implications of these roles for planning practice in terms of the spatial/organizational level of planning, time horizon, functional planning areas, political/decision making system and planning's position in this system.  相似文献   

16.
Is Amsterdam the “ideal city?” Many of the social, economic, and environmental problems facing Amsterdam are considerably less than those in cities in the USA, and in most cases, Western Europe. Amsterdam, at this moment in history, might be the world's greatest city because of its ability to ensure basic necessities, freedom, and creativity. Tolerance of drugs, sexual freedom, along with the integration of different races helps reduce many of the “social problems” faced by most cities. We have compared, on a per capita basis, differences between Amsterdam/Holland and the USA. The Netherlands is a tiny country, and comparisons are made on a city and per capita numbers at the national level. Our data show that Amsterdam has lower crime, murder, rape, drug usage (cocaine, marijuana), teenage pregnancy, diabetes, obesity, suicide, abortion rates, infant mortality, dependence on fossil fuels, and homelessness, and racial segregation is considerably less. People live longer because of Amsterdam's walkability and bike usage and access to parks. Indeed, the Netherlands leads both Western European and the USA in the proportion of trips made walking and bicycling, with significantly reduced car dependency. Ghettos are nearly non-existent compared with the segregation in the 1940s/1950s. Quality housing is supplied to everyone that gives pride of place compared with the stark, cold, and institutional “projects” provided by the US federal government. Amsterdam leads Western Europe by 35% in social housing, compared with runner-up UK, which has significantly less. The modernism of the 1960s where the poor were warehoused is nearly all gone. People living in Amsterdam seem more tolerant, secure, happier, and healthier compared with citizens in the USA. Great cities provide opportunities for all citizens to enhance their lives and ensure an unrivalled level of freedom. We demonstrate that social and environmental justice are tied together. Amsterdam is by no means perfect, but in comparison with many other democratic industrial cities, it is a far better place for citizens of all races, religions, and incomes.  相似文献   

17.
Adaptive Comanagement for Building Resilience in Social–Ecological Systems   总被引:19,自引:4,他引:15  
Ecosystems are complex adaptive systems that require flexible governance with the ability to respond to environmental feedback. We present, through examples from Sweden and Canada, the development of adaptive comanagement systems, showing how local groups self-organize, learn, and actively adapt to and shape change with social networks that connect institutions and organizations across levels and scales and that facilitate information flows. The development took place through a sequence of responses to environmental events that widened the scope of local management from a particular issue or resource to a broad set of issues related to ecosystem processes across scales and from individual actors, to group of actors to multiple-actor processes. The results suggest that the institutional and organizational landscapes should be approached as carefully as the ecological in order to clarify features that contribute to the resilience of social–ecological systems. These include the following: vision, leadership, and trust; enabling legislation that creates social space for ecosystem management; funds for responding to environmental change and for remedial action; capacity for monitoring and responding to environmental feedback; information flow through social networks; the combination of various sources of information and knowledge; and sense-making and arenas of collaborative learning for ecosystem management. We propose that the self-organizing process of adaptive comanagement development, facilitated by rules and incentives of higher levels, has the potential to expand desirable stability domains of a region and make social–ecological systems more robust to change.Published online  相似文献   

18.
Saltwater fishing tournaments in the United States are generally not regulated nor are there different fishing regulations for tournament and nontournament anglers. Although much is known about those who participate in fishing tournaments in terms of their fishing motivations, attitudes, and characteristics, much less is known at the angler population level regarding their preferences for tournament opportunities. Using a stated preference choice model with hypothetical scenarios to simulate participation choices and understand preferences, study objectives were to identify angler preferences for various types of tournament fishing “products.” Four tournament policy characteristics were investigated: promotion of catch and release, bait restrictions, whether a percentage of the tournament entrance fee should go to support fishery management activities, and whether a tournament should be a nonprofit or profit-making venture. Three expectation attributes were inserted: tournament size, trip cost per day, and whether a tournament is family friendly. We sent seven different versions of the mail questionnaire to 1,633 anglers. Of 795 returns, 648 were used for estimating conditional logit models. Analysis indicated that a scenario with no management interventions was not most preferred. Anglers most preferred a conservation-oriented option that introduced additional management measures. Overall, scenarios with management interventions were more favored than the status quo situation (with no management interventions). Although respondents showed reluctance to adopt other management-related options, results generally indicated they were increasingly concerned with sustainability of fish stocks and potential conflicts between tournament and nontournament users and preferred tournament products that reflect these concerns.  相似文献   

19.
The forests of Colombia are influenced by the actions of armed groups and, in many cases, their settlers are economically dependent on illicit crops. Up to the present armed conflict has simultaneously discouraged organized exploitation in some frontier areas, and encouraged unsustainable use of natural resources therein. The Colombian government seeks to end the conflict by pursuing peace negotiations, and to eradicate illicit crops. How will these policies affect the forests? The environmental consequences of these policies are not only dependent on the unlikely economic success of alternative development, but on making informed decisions about infrastructure development in affected areas.  相似文献   

20.
The estimation of leachate quantities produced in landfills is necessary to dimension the treatment plants allowing to reduce the polluting load of these effluents and consequently avoid their negative impacts on the environment. Different leachate quantification methods were used in this study to assess the leachate volume produced at the Oum Azza landfill. The water balance method give comparable estimations of leachate production to the Ouled Berjal landfill ratio. The first method showed average values between 487 and 495 m3/day for 2015, 2018, and 2019, and at the same time, the second method gave values between 470 and 477 m3/day for the same years. In contrast, the World Bank ratio showed high values that vary between 2260 and 2295 m3/day for 2015, 2018, and 2019. The on-site data and the statistical analysis showed us that the World Bank ratio is not adapted for the estimation of the leachates produced in Oum Azza landfill, while the water balance and the ratio of Ouled Berjal landfill allowed to give comparable results to reality.  相似文献   

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