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1.
Historical decline in coral reef growth after the Panama Canal   总被引:1,自引:0,他引:1  
Guzman HM  Cipriani R  Jackson JB 《Ambio》2008,37(5):342-346
The Panama Canal is near its vessel size and tonnage handling capacity, and Panamanians have decided to expand it. The expansion of the Canal may consider the historical long-lasting impacts on marine coastal habitats particularly on sensitive coral reefs. These potential impacts were discussed during the national referendum as were other equally important issues, such as its effects on forests, watersheds, and water supply. Coral growth rates provide a direct measure of coral fitness and past environmental conditions comparable to analyses of tree rings. We examined stable isotopes, metal geochemical tracers, and growth rates on a century-long (1880-1989) chronology based on 77 cores of the dominant reef-building coral Siderastrea siderea collected near the Caribbean entrance to the canal. Our results showed a gradual decline in coral growth unrelated to changes in sea surface temperature but linked to runoff and sedimentation to coastal areas resulting from the construction and operation of the Panama Canal.  相似文献   

2.
The maintenance of biodiversity by securing representative and well-connected habitat networks in managed landscapes requires a wise combination of protection, management, and restoration of habitats at several scales. We suggest that the integration of natural and social sciences in the form of "Two-dimensional gap analysis" is an efficient tool for the implementation of biodiversity policies. The tool links biologically relevant "horizontal" ecological issues with "vertical" issues related to institutions and other societal issues. Using forest biodiversity as an example, we illustrate how one can combine ecological and institutional aspects of biodiversity conservation, thus facilitating environmentally sustainable regional development. In particular, we use regional gap analysis for identification of focal forest types, habitat modelling for ascertaining the functional connectivity of "green infrastructures", as tools for the horizontal gap analysis. For the vertical dimension we suggest how the social sciences can be used for assessing the success in the implementation of biodiversity policies in real landscapes by identifying institutional obstacles while implementing policies. We argue that this interdisciplinary approach could be applied in a whole range of other environments including other terrestrial biota and aquatic ecosystems where functional habitat connectivity, nonlinear response to habitat loss and a multitude of economic and social interests co-occur in the same landscape.  相似文献   

3.
Conservation of the marine environment mainly focuses on threatened elements and more precisely on vulnerable and endangered species like birds and mammals. When dealing with the conservation of marine habitats, the scientific community is mainly interested in hot spots of diversity, like seagrass beds in Europe, or hot spots of endemism, like coral reefs in tropical areas. Nevertheless, using the example of a common and widespread marine invertebrate, the sandmason worm (Lanice conchilega, Polychaeta, Terebellidae), we show that vulnerability and rarity are not the only criteria to take into account in order to select the best natural element for conservation. This species can form dense beds that increase biodiversity, are attractive feeding grounds for birds and fishes, and have a high socioeconomic value. In consequence, they have a high functional value that should be considered as an important conservation stake. Through the example of the Chausey archipelago and the Bay of the Mont Saint-Michel (France), we propose a synthetic interdisciplinary approach to evaluate the conservation needs of these beds. The issue is even more pressing when one considers that these natural elements and many similar ones still do not benefit from any legal protection in Europe despite their high heritage value.  相似文献   

4.
McClanahan T  Maina J  Pet-Soede L 《Ambio》2002,31(7-8):543-550
Data were collected in southern Kenya on coral reef ecosystems and fisheries to assess the influence of the 1998 coral bleaching and mortality event. We compared benthic cover, sea urchin and fish abundance in unfished marine parks and fished reefs and the reef-associated fisheries 3 years before and after 1998. Hard and soft coral decreased while coralline algae increased in both management areas. Turf increased in marine parks and sponge and fleshy algae increased in the fished reefs. Sea urchin grazer biomass was unchanged over this period and the fish community changed less than benthic cover. In general, butterflyfish, damselfish and wrasses were negatively influenced while surgeonfish and a few uncommon families were positively influenced by the substratum change. There was a 17% increase in fishing effort as measured by fishermen per day at each landing site and the total demersal catch declined by 8% and the catch per man declined by 21% after 1998. The decline in the total catch and CPUE combined with the increase in effort suggest an overexploited fishery and this makes it difficult to distinguish changes caused by coral mortality or fishing effort. The price of fish increased over this period and this caused an 18% increase in the total value of the fishery but no difference in the net income of individual fishermen.  相似文献   

5.
Coastal habitats are situated on the border between land and sea, and ecosystem structure and functioning is influenced by both marine and terrestrial processes. Despite this, most scientific studies and monitoring are conducted either with a terrestrial or an aquatic focus. To address issues concerning climate change impacts in coastal areas, a cross-ecosystem approach is necessary. Since habitats along the Baltic coastlines vary in hydrology, natural geography, and ecology, climate change projections for Baltic shore ecosystems are bound to be highly speculative. Societal responses to climate change in the Baltic coastal ecosystems should have an ecosystem approach and match the biophysical realities of the Baltic Sea area. Knowledge about ecosystem processes and their responses to a changing climate should be integrated within the decision process, both locally and nationally, in order to increase the awareness of, and to prepare for climate change impacts in coastal areas of the Baltic Sea.  相似文献   

6.
Muhando CA  Kuguru BL  Wagner GM  Mbije NE  Ohman MC 《Ambio》2002,31(7-8):558-561
This study examined the distribution and abundance of corallimorpharians (Cnidaria, Anthozoa) in Tanzania in relation to different aspects of the coral reef environment. Five reefs under varying degrees of human disturbance were investigated using the line intercept transect and point technique. Corallimorpharian growth and the composition of the substratum were quantified in different habitats within reefs: the inner and middle reef flat, the reef crest, and at the 2 and 4 m depths on the reef slope. Corallimorpharians occurred on all the reefs and 5 species were identified: Rhodactis rhodostoma, R. mussoides, Ricordea yuma, Actinodiscus unguja and A. nummiforme. R. rhodostoma was the dominant corallimorpharian at all sites. Within reefs, they had the highest densities in the shallow habitats. While R. rhodostoma occurred in all habitats, the other corallimorpharian species showed uneven distributions. Corallimorpharians ranked second, after scleractinian coral, in percent living cover. Results from this study suggested that corallimorpharians benefitted from disturbance compared with other sessile organisms. They preferred inhabiting areas with dead coral, rock and rubble whilst live coral was avoided. There was a positive relationship between percent cover of corallimorpharians and water turbidity and they dominated the more disturbed reefs, i.e. reefs that were affected by higher nutrient loads and fishing.  相似文献   

7.
Freshwater ecosystems are important for global biodiversity and provide essential ecosystem services. There is consensus in the scientific literature that freshwater ecosystems are vulnerable to the impacts of environmental change, which may trigger irreversible regime shifts upon which biodiversity and ecosystem services may be lost. There are profound uncertainties regarding the management and assessment of the vulnerability of freshwater ecosystems to environmental change. Quantitative approaches are needed to reduce this uncertainty. We describe available statistical and modeling approaches along with case studies that demonstrate how resilience theory can be applied to aid decision-making in natural resources management. We highlight especially how long-term monitoring efforts combined with ecological theory can provide a novel nexus between ecological impact assessment and management, and the quantification of systemic vulnerability and thus the resilience of ecosystems to environmental change.  相似文献   

8.
Francis J  Nilsson A  Waruinge D 《Ambio》2002,31(7-8):503-511
This article reviews the governance and management of Marine Protected Areas (MPAs), and the coral reefs they contain, in the eastern African Region. This includes the Comoros, Kenya, Madagascar, Mauritius, Mozambique, Tanzania, and the Seychelles. Three generations or categories of MPAs are distinguished: i) small areas for protection of a single species or unique marine habitat; iii) large multiple use MPAs designed for coastal development as well as biodiversity protection; and iii) MPAs managed by a nongovernmental organization (NGO) or the private sector. Each of these MPA types is examined according to the policies, legislation, and management systems they entail as well as the economic and community situation they operate within. The paper also provides a review of some eastern African MPAs in terms of their size and location, the type of MPA, zonation schemes, and financial status. The successes of the different types of MPAs are discussed based on specific indicators, such as changes in biodiversity, infrastructure, compliance to regulations and the level of involvement of primary stakeholders in the management. From the review it is clear that a fourth generation of MPAs may be forthcoming; community-based MPAs. Although lack of data makes it difficult to assess the effectiveness of these different categories of MPAs, it is clear that no MPA can succeed without support of the local communities. Generally, the results of the analysis are promising for MPAs, however a lack of data is hampering a deeper analysis. The major issues facing MPAs in the region are highlighted, as well as some regional initiatives striving to address these issues. A number of recommendations are made, aiming to strengthen the establishment and management of MPAs in the eastern African region.  相似文献   

9.
Coastal and other area resources such as tidal wetlands, seagrasses, coral reefs, wetlands, and other ecosystems are often harmed by environmental damage that might be inflicted by human actions, or could occur from natural hazards such as hurricanes. Society may wish to restore resources to offset the harm, or receive compensation if this is not possible, but faces difficult choices among potential compensation projects. The optimal amount of restoration efforts can be determined by non-market valuation methods, service-to-service, or resource-to-resource approaches such as habitat equivalency analysis (HEA). HEA scales injured resources and lost services on a one-to-one trade-off basis. Here, we present the main differences between the HEA approach and other non-market valuation approaches. Particular focus is on the role of the social discount rate, which appears in the HEA equation and underlies calculations of the present value of future damages. We argue that while HEA involves elements of economic analysis, the assumption of a one-to-one trade-off between lost and restored services sometimes does not hold, and then other non-market economic valuation approaches may help in restoration scaling or in damage determination.  相似文献   

10.
Payet R  Agricole W 《Ambio》2006,35(4):182-189
The Seychelles is a small island state in the western Indian Ocean that is vulnerable to the effects of climate change. This vulnerability led the Intergovernmental Panel on Climate Change (IPCC) in 2001 to express concern over the potential economic and social consequences that may be faced by small island states. Small island states should be prepared to adapt to such changes, especially in view of their dependence on natural resources, such as water and coral reefs, to meet basic human welfare needs. Analysis of long-term data for precipitation, air temperature, and sea-surface temperature indicated that changes are already observable in the Seychelles. The increase in dry spells that resulted in drought conditions in 1999 and the 1998 mass coral bleaching are indicative of the events that are likely to occur under future climate change. Pre-IPCC Third Assessment Report scenarios and the new SRES scenarios are compared for changes in precipitation and air surface temperature for the Seychelles. These intercomparisons indicate that the IS92 scenarios project a much warmer and wetter climate for the Seychelles than do the SRES scenarios. However, a wetter climate does not imply readily available water, but rather longer dry spells with more intense precipitation events. These observations will likely place enormous pressures on water-resources management in the Seychelles. Similarly, sea-surface temperature increases predicted by the HADCM3 model will likely trigger repeated coral-bleaching episodes, with possible coral extinctions within the Seychelles region by 2040. The cover of many coral reefs around the Seychelles have already changed, and the protection of coral-resilient areas is a critical adaptive option.  相似文献   

11.
Philipson P  Lindell T 《Ambio》2003,32(8):586-593
The dramatic bleaching events on the coral reefs recently have enhanced the need for environmental monitoring. Remote sensing is an important constituent for monitoring of reefs, and an invaluable complement to field observations. This paper discusses the possibilities and limitations of present high resolution satellites for mapping and monitoring coral reefs. The sensors with the best spatial and radiometric resolution available today, e.g. IKONOS, can be useful for mapping and monitoring of reefs, but they are too costly for global surveys. However, our coral bleaching studies indicate that massive bleaching could be detected even from satellites with lower resolution, like Landsat, SPOT, and IRS. They could also be useful for coarser, from a spatial and thematic point of view, global mapping and updating purposes. A more detailed monitoring requires both better spatial resolution and spectral resolution than today's sensors. In the future, it is necessary to construct a more reef specific sensor with a few specially selected narrow bands and a good spatial, radiometric and temporal resolution.  相似文献   

12.
Novel urban ecosystems, biodiversity, and conservation   总被引:2,自引:0,他引:2  
With increasing urbanization the importance of cities for biodiversity conservation grows. This paper reviews the ways in which biodiversity is affected by urbanization and discusses the consequences of different conservation approaches. Cities can be richer in plant species, including in native species, than rural areas. Alien species can lead to both homogenization and differentiation among urban regions. Urban habitats can harbor self-sustaining populations of rare and endangered native species, but cannot replace the complete functionality of (semi-)natural remnants. While many conservation approaches tend to focus on such relict habitats and native species in urban settings, this paper argues for a paradigm shift towards considering the whole range of urban ecosystems. Although conservation attitudes may be challenged by the novelty of some urban ecosystems, which are often linked to high numbers of nonnative species, it is promising to consider their associated ecosystem services, social benefits, and possible contribution to biodiversity conservation.  相似文献   

13.
Climate change represents one of the most pressing societal and scientific challenges of our time. While much of the current research on climate change focuses on future prediction, some of the strongest signals of warming can already be seen in Arctic and alpine areas, where temperatures are rising faster than the global average, and in the oceans, where the combination of rising temperatures and acidification due to increased CO2 concentrations has had catastrophic consequences for sensitive marine organisms inhabiting coral reefs. The scientific papers highlighted as part of this anniversary issue represent some of the most impactful advances in our understanding of the consequences of anthropogenic climate change. Here, we reflect on the legacy of these papers from the biotic perspective.  相似文献   

14.
Current observed as well as projected changes in biodiversity are the result of multiple interacting factors, with land use and climate change often marked as most important drivers. We aimed to disentangle the separate impacts of these two for sets of vascular plant, bird, butterfly and dragonfly species listed as characteristic for European dry grasslands and wetlands, two habitats of high and threatened biodiversity. We combined articulations of the four frequently used SRES climate scenarios and associated land use change projections for 2030, and assessed their impact on population trends in species (i.e. whether they would probably be declining, stable or increasing). We used the BIOSCORE database tool, which allows assessment of the effects of a range of environmental pressures including climate change as well as land use change. We updated the species lists included in this tool for our two habitat types. We projected species change for two spatial scales: the EU27 covering most of Europe, and the more restricted biogeographic region of ‘Continental Europe’. Other environmental pressures modelled for the four scenarios than land use and climate change generally did not explain a significant part of the variance in species richness change. Changes in characteristic bird and dragonfly species were least pronounced. Land use change was the most important driver for vascular plants in both habitats and spatial scales, leading to a decline in 50–100% of the species included, whereas climate change was more important for wetland dragonflies and birds (40–50 %). Patterns of species decline were similar in continental Europe and the EU27 for wetlands but differed for dry grasslands, where a substantially lower proportion of butterflies and birds declined in continental Europe, and 50 % of bird species increased, probably linked to a projected increase in semi-natural vegetation. In line with the literature using climate envelope models, we found little divergence among the four scenarios. Our findings suggest targeted policies depending on habitat and species group. These are, for dry grasslands, to reduce land use change or its effects and to enhance connectivity, and for wetlands to mitigate climate change effects.  相似文献   

15.
Densely occupied drainage basins and coastal zones in developing countries that are facing economic growth are likely to suffer from moderate to severe environmental impacts regarding different issues. The catchment basins draining towards the Atlantic coast from northeastern to southern Brazil include a wide range of climatic zones and diverse ecosystems. Within its borders lies the Atlantic rain forest, significant extensions of semiarid thorn forests (caatinga), vast tree and scrub woodlands (cerrado) and most of the 6670 km of the Brazilian coast and its marine ecosystems. In recent decades, human activities have increasingly advanced over these natural resources. Littoralization has imposed a burden on coastal habitats and communities. Most of the native vegetation of the cerrado and caatinga was removed and only 7% of the original Atlantic rainforest still exists. Estuaries, bays and coastal lagoons have been irreversibly damaged. Land uses, damming and water diversion have become the major driving forces for habitat loss and aquatic ecosystem modification. Regardless of the contrast between the drought-affected northeastern Brazil and the much more prosperous and industrialized southeastern/southern Brazil, the impacts on habitat and communities were found equally severe in both cases. Attempts to halt environmental degradation have not been effective. Instead of focusing on natural resources separately, it is suggested that more integrated environmental policies that focus on aquatic ecosystems integrity are introduced.  相似文献   

16.
We present a synoptic, participatory vulnerability assessment tool to help identify the likely impacts of climate change and human activity in coastal areas and begin discussions among stakeholders on the coping and adaptation measures necessary to minimize these impacts. Vulnerability assessment tools are most needed in the tropical Indo-Pacific, where burgeoning populations and inequitable economic growth place even greater burdens on natural resources and support ecosystems. The Integrated Coastal Sensitivity, Exposure, and Adaptive Capacity for Climate Change (I-C-SEA Change) tool is built around a series of scoring rubrics to guide non-specialists in assigning scores to the sensitivity and adaptive capacity components of vulnerability, particularly for coral reef, seagrass, and mangrove habitats, along with fisheries and coastal integrity. These scores are then weighed against threat or exposure to climate-related impacts such as marine flooding and erosion. The tool provides opportunities for learning by engaging more stakeholders in participatory planning and group decision-making. It also allows for information to be collated and processed during a “town-hall” meeting, facilitating further discussion, data validation, and even interactive scenario building.

Electronic supplementary material

The online version of this article (doi:10.1007/s13280-015-0652-x) contains supplementary material, which is available to authorized users.  相似文献   

17.
Changes in climate, land-use and pollution are having disproportionate impacts on ecosystems and biodiversity of arctic and mountain ecosystems. While these impacts are well-documented for many areas of the Arctic and alpine regions, some isolated and inaccessible mountain areas are poorly studied. Furthermore, even in well-studied regions, assessments of biodiversity and species responses to environmental change are biased towards vascular plants and cryptogams, particularly bryophytes are far less represented. This paper aims to document the environments of the remote and inaccessible Altai-Sayan mountain mires and particularly their bryofloras where threatened species exist and species new to the regional flora are still being found. As these mountain mires are relatively inaccessible, changes in drivers of change and their ecosystem and biodiversity impacts have not been monitored. However, the remoteness of the mires has so far protected them and their species. In this study, we describe the mires, their bryophyte species and the expected impacts of environmental stressors to bring attention to the urgency of documenting change and conserving these pristine ecosystems.Supplementary InformationThe online version contains supplementary material available at 10.1007/s13280-021-01596-w.  相似文献   

18.
For many years, the planning and management of terrestrial areas has been supported by a detailed knowledge of the distribution of habitats and their associated species. However, the detailed mapping of biological resources in extent coastal areas, such as the Norwegian coastal zone, is unrealistic due to its enormous coastline. Here, we present a useful and feasible approach and a set of simple, cost-effective methods which are suitable for providing a broad-scale overview of marine habitats and fish resources. This approach was developed in conjunction with a pioneer study conducted along the southern coast of the Skagerrak, where we combined knowledge gathered from local fishermen with scientific knowledge of important species and nature types to establish a coastal sea mapping program. GIS modeling tools were used in both the mapping program and to integrate local and scientific knowledge into digital maps made available to local area management. This multi-faceted approach, which combines local knowledge and scientific methods, provides valuable information with respect to marine biodiversity, and has been used extensively by local environmental management.  相似文献   

19.
Improvements in human wellbeing are dependent on improving ecosystems. Such considerations are particularly pertinent for regions of high ecological, but also social and cultural importance that are facing rapid change. One such region is the Great Barrier Reef (GBR). Although the GBR has world heritage status for its ‘outstanding universal value’, little is known about resident perceptions of its values. We surveyed 1545 residents, finding that absence of visible rubbish; healthy reef fish, coral cover, and mangroves; and iconic marine species, are considered to be more important to quality of life than the jobs and incomes associated with industry (most respondents were dissatisfied with the benefits they received from industry). Highly educated females placed more importance on environmental non-use values than other respondents; less educated males and those employed in mining found non-market use-values relatively more important. Environmental non-use values emerged as the most important management priority for all.

Electronic supplementary material

The online version of this article (doi:10.1007/s13280-014-0554-3) contains supplementary material, which is available to authorized users.  相似文献   

20.
National Park Development in China: Conservation or Commercialization?   总被引:1,自引:0,他引:1  
Wang G  Innes JL  Wu SW  Krzyzanowski J  Yin Y  Dai S  Zhang X  Liu S 《Ambio》2012,41(3):247-261
The rapid development of parks and ecotourism in China has attracted worldwide attention, not only for the beauty of the landscape that the parks are protecting but also for their abundant and often unique biodiversity. However, in some areas, the development of ecotourism has actually led to the degradation of local ecological, economic, and social systems. Using National Forest Parks for demonstration, this article analyzes the current political, institutional, legal, environmental, and economic issues concerning National Parks in China, and examines their potential future development. Although the intention of National Park systems in China is to raise environmental quality, and to protect biodiversity and social livelihoods, their success has varied. Future success will be measured by their capacity to reduce poverty, to promote long-term rehabilitation of wildlife habitats, and to simultaneously protect Chinese culture and biodiversity.  相似文献   

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