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1.
The frequency and severity of mass coral bleaching events are predicted to increase as sea temperatures continue to warm under a global regime of rising ocean temperatures. Bleaching events can be disastrous for coral reef ecosystems and, given the number of other stressors to reefs that result from human activities, there is widespread concern about their future. This article provides a strategic framework from the Great Barrier Reef to prepare for and respond to mass bleaching events. The framework presented has two main inter-related components: an early warning system and assessment and monitoring. Both include the need to proactively and consistently communicate information on environmental conditions and the level of bleaching severity to senior decision-makers, stakeholders, and the public. Managers, being the most timely and credible source of information on bleaching events, can facilitate the implementation of strategies that can give reefs the best chance to recover from bleaching and to withstand future disturbances. The proposed framework is readily transferable to other coral reef regions, and can easily be adapted by managers to local financial, technical, and human resources.  相似文献   

2.
Because environmental conservation can remove scarce natural resources from competing uses, it is important to gain support for conservation programs by demonstrating that management actions have been effective in achieving their goals. One way to do this is to show that selected significant environmental variables (indicators) vary between managed and unmanaged areas or change over time following implementation of a management regime. However, identifying indicators that reflect environmental conditions relevant to management practices has proven difficult. This paper focuses on developing a framework for choosing indicators in a coral reef habitat. The framework consisted of three phases: (1) information gathering to identify candidate variables; (2) field-testing candidate variables at sites that differ in intensity of human activity, thus identifying potential indicators; and (3) evaluating potential indicators against a set of feasibility criteria to identify the most useful indicators. To identify indicators suitable to measure the success of a management strategy to reduce anchor damage to a coral reef, 24 candidate variables were identified and evaluated at sites with different intensities of anchoring. In this study, measures that reflected injuries to coral colonies were generally more efficient than traditional measures of coral cover in describing the effects of anchoring. The number of overturned colonies was identified as the single most useful indicator of coral reef condition associated with anchoring intensities. The indicator selection framework developed here has the advantages of being transparent, cost efficient, and readily transferable to other types of human activities and management strategies.  相似文献   

3.
There is a consensus that Marine Protected Area (MPA) performance needs regular evaluation against clear criteria, incorporating counterfactual comparisons of ecological and socio-economic performance. However, these evaluations are scarce at the global level. We compiled self-reports from managers and researchers of 78 coral reef-based MPAs world-wide, on the conservation and welfare improvements that their MPAs provide. We developed a suite of performance measures including fulfilment of design and management criteria, achievement of aims, the cessation of banned or destructive activities, change in threats, and measurable ecological and socio-economic changes in outcomes, which we evaluated with respect to the MPA’s age, geographical location and main aims. The sample was found to be broadly representative of MPAs generally, and suggests that many MPAs do not achieve certain fundamental aims including improvements in coral cover over time (in 25% of MPAs), and conflict reduction (in 25%). However, the large majority demonstrated improvements in terms of slowing coral loss, reducing destructive uses and increasing tourism and local employment, despite many being small, underfunded and facing multiple large scale threats beyond the control of managers. However spatial comparisons suggest that in some regions MPAs are simply mirroring outside changes, with demonstrates the importance of testing for additionality. MPA benefits do not appear to increase linearly over time. In combination with other management efforts and regulations, especially those relating to large scale threat reduction and targeted fisheries and conflict resolution instruments, MPAs are an important tool to achieve coral reef conservation globally. Given greater resources and changes which incorporate best available science, such as larger MPAs and no-take areas, networks and reduced user pressure, it is likely that performance could further be enhanced. Performance evaluation should test for the generation of additional ecological and socio-economic improvements over time and compared to unmanaged areas as part of an adaptive management regime.  相似文献   

4.
In the history of disasters in Venice, there are implications for modern times in terms of complex systems management and emerging threats, in particular from examples of risk management and resilience achieved by the Venetian state during outbreaks of the plague. In fourteenth century Venice, risk assessment the way we practice it today would fail to provide meaningful recommendations to reduce the casualty rate of the plague epidemic because the cause and transmission of the disease was not understood. Instead, a set of systemic actions across the social, economic, and transportation networks of the city taken by officials and doctors eventually slowed and arguably stopped the spread of the disease. These latter actions are an early example of what is now considered resilience management. Resilience management improves a complex system’s ability to prepare, absorb, recover, and adapt to unexpected threats and does so by address the capabilities at a system, rather than component, level. Resilience management can be a guide to addressing current issues of population growth and rising sea level in modern day Venice and across the globe. This paper calls for integration of resilience assessment in comprehensive risk and resilience management framework.  相似文献   

5.
There is a close relationship between ports and reef areas, mainly because reefs provide protection to vessels against extreme weather events like storms and hurricanes. This historical relationship has generated severe impacts on reef ecosystems. In order to identify the main impacts from the construction of port facilities in shallow coral reef areas, we analyzed and described the effects of land reclamation and coastal structure construction associated to port growth throughout a century in the Sistema Arrecifal Veracruzano National Park, Mexico. We used aerial photographs and maps of the nineteenth and early twentieth century to assess the impacts caused by port expansion activities on shallow coral reefs. Three types of impacts were identified: (a) direct reef area loss caused by landfills and perpendicular coastal structures construction leading to the loss of nearly 50 % of the fringing reef near to the port; (b) fragmentation in short- and medium-term scale, which affects two fringing reefs, and (c) long-term modification of coastal dynamics leading to sedimentation and loss of a complete reef area. On the eve of a new expansion of Veracruz Port, we used the New Port Project Plan, long-shore net drift geomorphic indicators and the port impact typology from the 100-year period assessment to evaluate a possible future scenario. The scenario describes how the new expansion project will repeat the three types of impacts affecting a whole reef area, which is currently part of the National Park.  相似文献   

6.
Marine protected areas (MPAs) provide place-based management of marine ecosystems through various degrees and types of protective actions. Habitats such as coral reefs are especially susceptible to degradation resulting from climate change, as evidenced by mass bleaching events over the past two decades. Marine ecosystems are being altered by direct effects of climate change including ocean warming, ocean acidification, rising sea level, changing circulation patterns, increasing severity of storms, and changing freshwater influxes. As impacts of climate change strengthen they may exacerbate effects of existing stressors and require new or modified management approaches; MPA networks are generally accepted as an improvement over individual MPAs to address multiple threats to the marine environment. While MPA networks are considered a potentially effective management approach for conserving marine biodiversity, they should be established in conjunction with other management strategies, such as fisheries regulations and reductions of nutrients and other forms of land-based pollution. Information about interactions between climate change and more “traditional” stressors is limited. MPA managers are faced with high levels of uncertainty about likely outcomes of management actions because climate change impacts have strong interactions with existing stressors, such as land-based sources of pollution, overfishing and destructive fishing practices, invasive species, and diseases. Management options include ameliorating existing stressors, protecting potentially resilient areas, developing networks of MPAs, and integrating climate change into MPA planning, management, and evaluation.  相似文献   

7.
We present a new approach for characterizing the potential of scientific studies to reduce conflict among stakeholders in an analytic-deliberative environmental decision-making process. The approach computes a normalized metric, the Expected Consensus Index of New Research (ECINR), for identifying where additional scientific research will best support improved decisions and resolve possible conflicts over preferred management actions. The ECINR reflects the expected change in agreement among parties over preferred management actions with the implementation and consideration of new scientific studies. We demonstrate the ECINR method based on a preliminary application to coral reef protection and restoration in the Guánica Bay Watershed, Puerto Rico, focusing on assessing and managing anthropogenic stressors, including sedimentation and pollution from land-based sources such as sewage, agriculture, and development. Structured elicitations of values and beliefs conducted at a coral reef decision support workshop held at La Parguera, Puerto Rico, are used to develop information for illustrating the methodology. The ECINR analysis was focused on a final study group of seven stakeholders, consisting of resource managers and scientists, who were not in agreement on the efficacy and respective benefits of reducing loadings from three sources: sewage, agriculture, and development. The scenario assumed that loadings would be reduced incrementally from each source through a series of management steps, which would be ranked in order of maximizing anticipated benefits. An examination of whether beliefs exhibited greater confidence and coherence between stakeholders when informed by plausible study results followed. The results suggest that new scientific research would be generally likely to bring people who initially disagreed to agree. Seventy-five percent of the hypothetical research results were projected to result in more agreement among the stakeholders. However, there can be situations where prior beliefs may be too different from the study results to shift perspectives enough to result in more agreement. Furthermore, in a few cases, hypothetical research results were projected to lead to more conflict among stakeholders. Priority research, according to the seven stakeholders, would be to quantify loadings from agriculture and sewage, and not loadings from development, since it is predicted to make little difference in the outcome. Assuming the stakeholders are conflict-averse, they would likely opt for research on sewage loadings as the highest priority. Though preliminary, these results suggest that ECINR can provide useful insights into the social implications of a research program.  相似文献   

8.
In many ecosystems the effects of disturbance can be cryptic and disturbance may vary in subtle spatiotemporal ways. For instance, we know that bark beetle outbreaks are more frequent in temperate forests during droughts; however, we have little idea about why they occur in some locations and not others. Understanding biotic and abiotic factors promoting bark beetle outbreaks can be critical to predicting and responding to pest outbreaks. Here we address the environmental factors which are associated with Ips confusus outbreaks during the 2002 widespread drought within the distribution range of pinyon pine woodlands in Arizona. We used univariate statistics to test if whether tree characteristics, other herbivores, stand properties, soil type, wind, and topography were associated with I. confusus outbreak, and logistic regression to create a predictive model for the outbreaks. We found that I. confusus attacks occur in low elevation stands on steeper slopes, where favorable winds for I. confusus dispersion occur. I. confusus select larger trees, in high density stands with understory shrubs that exhibit phenotypic traits characteristic of resistance to stem-boring moths. The model was highly accurate, and explained 95% of the variability in occurrence (98% of the absences and 95% of the presences). Accurate prediction of the impacts of disturbance allow us to anticipate, minimize or mitigate for and eventually counteract its effects, especially those affecting diversity and ecosystem function. Identification of outbreak risk areas can guide regional and national management towards the reduction of infestation risk and enhancing conservation of pinyon-juniper woodlands.  相似文献   

9.
Shallow reefs (reef flats <1.5 m) in the northern Red Sea are impacted by growing tourism that includes swimmers, snorkellers and reef walkers but have largely been neglected in past studies. We selected a fringing reef along the lagoon of Dahab (Sinai, Egypt) as a model for a management strategy. Point-intercept line transects were used to determine substrate composition, coral community and condition, and the coral damage index (CDI) was applied. Approximately 84% of the coral colonies showed signs of damage such as breakage, partial mortality or algal overgrowth, especially affecting the most frequent coral genus Acropora. Questionnaires were used to determine the visitors' socio-economic background and personal attitudes regarding snorkelling, SCUBA-diving and interest in visiting a prospective snorkelling trail. Experiencing nature (97%) was by far the strongest motivation, and interest in further education about reef ecology and skill training was high. Less experienced snorkellers and divers--the target group for further education and skill training--were those most prepared to financially support such a trail. We therefore recommend a guided underwater snorkelling trail and restricting recreational use to a less sensitive 'ecotourism zone' while protecting the shallow reef flat. Artificial structures can complete the trail and offer the opportunity to snorkel over deeper areas at unfavourable tide or wind conditions. This approach provides a strategy for the management and conservation of shallow-water reefs, which are facing increasing human impact here and elsewhere.  相似文献   

10.
Combating drought through preparedness   总被引:1,自引:0,他引:1  
Drought is a complex, slow–onset phenomenon that affects more people than any other natural hazard and results in serious economic, social, and environmental impacts. Although drought affects virtually all climatic regimes and has significant consequences in both developed and developing countries, its impacts are especially serious in developing countries where dryland agriculture predominates. The impacts of drought are often an indicator of unsustainable land and water management practices, and drought assistance or relief provided by governments and donors encourages land managers and others to continue these practices. This often results in a greater dependence on government and a decline in self–reliance. Moving from crisis to risk management will require the adoption of a new paradigm for land managers, governments, international and regional development organizations, and non–governmental organizations. This approach emphasizes preparedness, mitigation, and improved early warning systems (EWS) over emergency response and assistance measures. Article 10 of the Convention to Combat Desertification states that national action programmes should be established to identify the factors contributing to desertification and practical measures necessary to combat desertification and mitigate the effects of drought. In the past 10 years, there has been considerable recognition by governments of the need to develop drought preparedness plans and policies to reduce the impacts of drought. Unfortunately, progress in drought preparedness during the last decade has been slow because most nations lack the institutional capacity and human and financial resources necessary to develop comprehensive drought plans and policies. Recent commitments by governments and international organizations and new drought monitoring technologies and planning and mitigation methodologies are cause for optimism. The challenge is the implementation of these new technologies and methodologies. It is critical for governments that possess this experience to share it with others through regional and global networks. One way to accomplish this goal is to create a network of regional networks on drought preparedness to expedite the adoption of drought preparedness tools to lessen the hardships associated with severe and extended drought episodes.  相似文献   

11.
Applications of Turbidity Monitoring to Forest Management in California   总被引:1,自引:1,他引:0  
Many California streams have been adversely affected by sedimentation caused by historic and current land uses, including timber harvesting. The impacts of timber harvesting and logging transportation systems on erosion and sediment delivery can be directly measured, modeled, or inferred from water quality measurements. California regulatory agencies, researchers, and land owners have adopted turbidity monitoring to determine effects of forest management practices on suspended sediment loads and water quality at watershed, project, and site scales. Watershed-scale trends in sediment discharge and responses to current forest practices may be estimated from data collected at automated sampling stations that measure turbidity, stream flow, suspended sediment concentrations, and other water quality parameters. Future results from these studies will provide a basis for assessing the effectiveness of modern forest practice regulations in protecting water quality. At the project scale, manual sampling of water column turbidity during high stream flow events within and downstream from active timber harvest plans can identify emerging sediment sources. Remedial actions can then be taken by managers to prevent or mitigate water quality impacts. At the site scale, manual turbidity sampling during storms or high stream flow events at sites located upstream and downstream from new, upgraded, or decommissioned stream crossings has proven to be a valuable way to determine whether measures taken to prevent post-construction erosion and sediment production are effective. Turbidity monitoring at the project and site scales is therefore an important tool for adaptive management. Uncertainty regarding the effects of current forest practices must be resolved through watershed-scale experiments. In the short term, this uncertainty will stimulate increased use of project and site-scale monitoring.  相似文献   

12.
The quality of the coral reefs in the Florida Keys is essential to sustain nature-based tourism in the Keys. The recently established marine reserves (MR) are expected to improve the reef environment, particularly coral and fish abundance and diversity. In this paper, a combined model of travel cost and contingent behavior was estimated in order to measure the non-market recreational benefits of reef quality improvements. The results indicated that an average visitor would undertake 43-80% more number of trips to the Florida Keys and experience a 69% increase in the use values per trip, as a result of the MR-induced reef quality improvements. The above non-market value estimates were further applied to evaluating alternative management proposals for funding the MR program. It was found that the annual management costs of the MR program would constitute an insignificant portion--only around one to 2%--of the annual recreational benefits that the MR would generate. The results provide a strong economic justification for designing user-based funding mechanisms in order to make the MR program self-sustaining in the future.  相似文献   

13.
The purpose of this paper is to explore the use of computer models, including artificial intelligence systems, in the context of risk assessment and management for wildfowl diseases. In particular, the paper focuses on avian cholera and botulism in U.S. wildfowl, which are a source of continuing concern to the U.S. Fish and Wildlife Service (USFWS). Severe outbreaks occur frequently, and some have been estimated to claim the lives of as many as 300 000 waterfowl. A potentially valuable support to the USFWS would be a set of models that assist in recognizing situations with high risk of an outbreak, assessing the anticipated severity of an outbreak, and advising on possible preventive measures. The USFWS has already initiated development of several potentially useful models. This paper reviews these as well as other related efforts, within the overall context of risk management for avian botulism and cholera.  相似文献   

14.
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   

15.
The effects of trampling on the coral communities of the outer reef flat and reef crest were investigated at Heron Island at the southern end of the Great Barrier Reef. Eighteen months of trampling at various intensities increased the percentage cover of unoccupied substrate and the cover of mobile rubble. The morphology of the coral was the most important feature relating to trampling resistance. Branching corals were reduced on the outer reef flat, and most broken branches were recorded in the initial phases of the experiment. The reef crest was much more resistant.A short-term trampling experiment showed that trampling detached a greater mass and larger fragments of coral on the outer reef flat than on the reef crest. Further trampling reduced the sizes of the detached fragments on the outer reef flat. A drift experiment indicated that greatest movement of fragments occurred on the reef crest and here the largest fragments moved greater distances.We concluded that all habitats would be changed by reef walking and that by one measure the outer reef flat was 16 times more vulnerable than the reef crest. The routes taken by reef walkers need to be chosen in relation to the trampling resistance of the habitat.  相似文献   

16.
A linkage between the condition of watersheds and adjacent nearshore coral reef communities is an assumed paradigm in the concept of integrated coastal management. However, quantitative evidence for this "catchment to sea" or "ridge to reef" relationship on oceanic islands is lacking and would benefit from the use of appropriate marine and terrestrial landscape indicators to quantify and evaluate ecological status on a large spatial scale. To address this need, our study compared the Hawai'i Watershed Health Index (HI-WHI) and Reef Health Index (HI-RHI) derived independently of each other over the past decade. Comparisons were made across 170 coral reef stations at 52 reef sites adjacent to 42 watersheds throughout the main Hawaiian Islands. A significant positive relationship was shown between the health of watersheds and that of adjacent reef environments when all sites and depths were considered. This relationship was strongest for sites facing in a southerly direction, but diminished for north facing coasts exposed to persistent high surf. High surf conditions along the north shore increase local wave driven currents and flush watershed-derived materials away from nearshore waters. Consequently, reefs in these locales are less vulnerable to the deposition of land derived sediments, nutrients and pollutants transported from watersheds to ocean. Use of integrated landscape health indices can be applied to improve regional-scale conservation and resource management.  相似文献   

17.
ABSTRACT: Drought has been a common feature in the United States during the past decade and has resulted in significant economic, social, and environmental impacts in virtually all parts of the nation. The purpose of this paper is two fold. First, the status of state drought planning is discussed to illustrate the significant increase in the number of states that have prepared response plans - from three states in 1982 to 27 in 1997. In addition, six states are now in various stages of plan development. Second, mitigative actions implemented by states in response to the series of severe drought years since 1986 are summarized. This information was obtained through a survey of states. The study concludes that states have made significant progress in addressing drought-related issues and concerns through the planning process. However, existing plans are still largely reactive in nature, treating drought in an emergency response mode. Mitigative actions adopted by states provide a unique archive that may be transferable to other states. Incorporating these actions into a more anticipatory, risk management approach to drought management will help states move away from the traditional crisis management approach.  相似文献   

18.
Coastal coral reefs, especially in the Florida Keys, are declining at a disturbing rate. Marine ecologists and reef scientists have emphasized the importance of establishing nonmarket values of coral reefs to assess the cost effectiveness of coral reef management and remediation programs. The purpose of this paper is to develop a travel cost-contingent valuation model of demand for trips to the Florida Keys focusing on willingness to pay (WTP) to preserve the current water quality and health of the coral reefs. The stated and revealed preference models allow the marginal valuation of recreationists to adjust depending on current and planned trip commitments in valuing nonmarginal policy changes in recreational opportunities. The integrated model incorporates key factors for establishing baseline amenity values for tourist dive sites, including perceptions of reef quality and dive conditions, the role of substitute sites, and the quality and availability of tourist facilities and recreation opportunities. The travel cost and WTP model differ in identifying critical variables and provide insight into the adjustment of trip decisions across alternative destination sites and the valuation of trips. In contrast to the travel cost model, a measure of the availability of substitute sites and total recreation activities does not have a significant impact on WTP valuations reported by snorkelers. Snorkelers engage in a relatively focused set of activities, suggesting that these recreationists may not shift expenditures to other sites or other recreation activities in the Florida Keys when confronted with increased access costs for the snorkeling experience.  相似文献   

19.
We present a decision support framework for science-based assessment and multi-stakeholder deliberation. The framework consists of two parts: a DPSIR (Drivers–Pressures–States–Impacts–Responses) analysis to identify the important causal relationships among anthropogenic environmental stressors, processes, and outcomes; and a Decision Landscape analysis to depict the legal, social, and institutional dimensions of environmental decisions. The Decision Landscape incorporates interactions among government agencies, regulated businesses, non-government organizations, and other stakeholders. It also identifies where scientific information regarding environmental processes is collected and transmitted to improve knowledge about elements of the DPSIR and to improve the scientific basis for decisions. Our application of the decision support framework to coral reef protection and restoration in the Florida Keys focusing on anthropogenic stressors, such as wastewater, proved to be successful and offered several insights. Using information from a management plan, it was possible to capture the current state of the science with a DPSIR analysis as well as important decision options, decision makers and applicable laws with a the Decision Landscape analysis. A structured elicitation of values and beliefs conducted at a coral reef management workshop held in Key West, Florida provided a diversity of opinion and also indicated a prioritization of several environmental stressors affecting coral reef health. The integrated DPSIR/Decision landscape framework for the Florida Keys developed based on the elicited opinion and the DPSIR analysis can be used to inform management decisions, to reveal the role that further scientific information and research might play to populate the framework, and to facilitate better-informed agreement among participants.  相似文献   

20.
ABSTRACT: Severe drought is a recurring problem for the United States, as illustrated by widespread economic, social, and environmental impacts. Recent drought episodes and the widespread drought conditions in 1996, 1998, and 1999 emphasized this vulnerability and the need for a more proactive, risk management approach to drought management that would place greater emphasis on preparedness planning and mitigation actions. Drought planning has become a principal tool of states and other levels of government to improve their response to droughts. For example, since 1982, the number of states with drought plans has increased from 3 to 29. Many local governments have also adopted drought or water shortage plans. Unfortunately, most state drought plans were established during the 1980s and early 1990s and emphasize emergency response or crisis management rather than risk management. This paper presents a substantive revision of a 10‐step drought planning process that has been applied widely in the United States and elsewhere. The revised planning process places more weight on risk assessment and the development and implementation of mitigation actions and programs. The goal of this paper is to encourage states to adopt this planning process in the revision of existing drought plans or, for states without plans, in the development of new plans.  相似文献   

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