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1.
Long-standing concerns about the effects of scallop dredging and demersal trawling on high diversity mudstone reef and cobble habitats in Lyme Bay, southwest England, were addressed by the exclusion of bottom towed fishing gear from a 206 km2 area in July 2008. A consortium led by Plymouth University Marine Institute was funded by the UK Department of Environment, Food and Rural Affairs to design and implement a study (initially funded for 3 years) to examine the effects of the closure on both nekton and epibenthos. This paper provides a detailed account of the methodology employed from survey design to data analysis to provide a protocol for future MPA monitoring programmes. Information on historical fishing effort, substrate distributions and current and previous closure boundaries was overlaid using GIS to locate suitable monitoring sites. Non-destructive and cost-effective techniques, including a towed high-definition video array and static baited video, were used to quantify changes in relative abundances of epibenthos and nekton over three years at sites previously fished but now closed to bottom towed fishing compared to both fished and un-fished reference sites. The monitoring programme as described provides a model for robust, cost-effective evaluation of the efficacy of policy instruments for feedback into the adaptive management cycle.  相似文献   

2.
Recent international policy developments require states to conserve at least 10% of coastal and marine areas by creating effectively managed and ecologically coherent networks of protected areas in the marine environment. In the framework of the PANACHE project, the current status of designation, management and monitoring of the network of marine protected areas (MPAs) of an important environmental, social and economic marine area: the English Channel (the Channel) was examined. Currently 224 MPAs exist belonging to 12 different designation categories and covering 17 440 km2, or approximately 20.3% of the project area in the Channel. International protection targets in the marine environment are thus met at this regional scale, although the individual contributions of the UK and France are considerably different, with French MPAs accounting for nearly 80% of the total area protected. Differences between countries are also found regarding MPA designation categories (11 in France, 6 in the UK, 1 in the Channel Islands) and management structures (with more actors involved in the UK) and approach, whereas the monitoring techniques used are similar, although more standardised in the UK. Pending challenges include greater within-country and cross-country MPA designation, monitoring and management simplicity, integration and coordination as well as the assessment of management effectiveness and ecological coherence of the Channel network of MPAs.  相似文献   

3.
A statutory two hundred and six square kilometre ‘closed area’ in Lyme Bay, South West England entered into force on the 11 July 2008 to protect the reef substrate and the associated biodiversity from the impacts of trawling and dredging with heavy demersal fishing gear. This case study provides an example of how the ecosystem approach has been incorporated into decision making for marine nature conservation and shows that despite sound ecological knowledge of a marine area, the current reliance on traditional neo-classical economic valuations for marine spatial planning can obscure other issues pertinent to the ecosystem approach. With the Government seeking win–win scenarios for stakeholders in the designation of Marine Conservation Zones under the Marine and Coastal Access Act, experience of marine spatial planning in Lyme Bay has revealed that a win–win must be a long-term goal based on a thorough evaluation of the environmental, social and economic values of marine biodiversity.  相似文献   

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Marine industries face a number of risks that necessitate careful analysis prior to making decisions on the siting of operations and facilities. An important emerging regulatory framework on environmental sustainability for business operations is the International Finance Corporation’s Performance Standard 6 (IFC PS6). Within PS6, identification of biodiversity significance is articulated through the concept of “Critical Habitat”, a definition developed by the IFC and detailed through criteria aligned with those that support internationally accepted biodiversity designations. No publicly available tools have been developed in either the marine or terrestrial realm to assess the likelihood of sites or operations being located within PS6-defined Critical Habitat. This paper presents a starting point towards filling this gap in the form of a preliminary global map that classifies more than 13 million km2 of marine and coastal areas of importance for biodiversity (protected areas, Key Biodiversity Areas [KBA], sea turtle nesting sites, cold- and warm-water corals, seamounts, seagrass beds, mangroves, saltmarshes, hydrothermal vents and cold seeps) based on their overlap with Critical Habitat criteria, as defined by IFC. In total, 5798×103 km2 (1.6%) of the analysis area (global ocean plus coastal land strip) were classed as Likely Critical Habitat, and 7526×103 km2 (2.1%) as Potential Critical Habitat; the remainder (96.3%) were Unclassified. The latter was primarily due to the paucity of biodiversity data in marine areas beyond national jurisdiction and/or in deep waters, and the comparatively fewer protected areas and KBAs in these regions. Globally, protected areas constituted 65.9% of the combined Likely and Potential Critical Habitat extent, and KBAs 29.3%, not accounting for the overlap between these two features. Relative Critical Habitat extent in Exclusive Economic Zones varied dramatically between countries. This work is likely to be of particular use for industries operating in the marine and coastal realms as an early screening aid prior to in situ Critical Habitat assessment; to financial institutions making investment decisions; and to those wishing to implement good practice policies relevant to biodiversity management. Supplementary material (available online) includes other global datasets considered, documentation and justification of biodiversity feature classification, detail of IFC PS6 criteria/scenarios, and coverage calculations.  相似文献   

7.
基于海岸带综合管理的理念,通过海域生态环境敏感性评价与海域生物多样性保护重要性评价,综合利用地理相关分析法、空间叠置法等定性和定量分区相结合的方法进行海洋生物多样性保护空间规划分区划界,提出了海洋生物多样性保护空间规划分区体系,将规划区域划分为生物多样性重点保护区、生物多样性养护区和生物多样性保护重点监督区.以福建泉州湾为案例,应用海洋生物多样性保护空间规划分区体系,得出泉州湾生物多样性保护极重要地区是泉州湾河口湿地省级自然保护区,泉州湾生物多样性保护比较重要地区是晋江河口、洛阳江河口、晋江南岸地区及清源山.泉州湾海洋生物多样性保护空间规划分区方案共划定26个分区,包括生物多样性重点保护区3个,生物多样性养护区14个,生物多样性保护重点监督区9个.泉州湾的应用结果表明,本研究提出的海洋生物多样性保护空间规划分区体系具有一定的可行性和可操作性,可为泉州湾生物多样性保护管理提供重要科学依据.  相似文献   

8.
Substantial changes are taking place in the coastal landscape as a result of rapid urbanization. A series of environmental and resource problems have emerged owing to rapid urban development, including encroachment of agricultural land, land reclamation, silt deposition in rivers, and severe flooding. These problems have had a significant impact on sustainable development in Lingding Bay, the largest estuary of the Pearl River. This paper demonstrates that remote sensing can be effective in monitoring the dynamics of coastal zones, such as coastline movement, urban expansion, land-use changes, and migration of shoals and deep-water channels. Remote sensing data from 1978 to 1998 were used to detect the accelerating changes that have taken place in the study area. A hybrid approach has proved to be an effective way of improving remote sensing image classification, with multi-temporal compound imaging, for coastal change analysis. Geographic information system (Intergraph's modular GIS environment, MGE) software was used to assist planners in the analysis of such changes, by combining the maps from 1974, 1989 to 1997 and integrating the multiple (spatial and attribute) databases. The result demonstrates that: (1) the Pearl River estuary is being reclaimed, estuarine waterways are getting narrower; the area of water near Humen town has narrowed by 4–6 km; (2) shoals in Lingding Bay have reduced the area of water by 114 km2 over the past 23 years; the area of deep-water channels has declined by ∼24 km2, even with dredging; on average, the area of water has decreased by 5.9 km2 annually; western channels migrated eastwards 0.8 and 1.1 km during the first and second 10-year period, respectively; according to this scenario, the western channel will disappear from Lingding Bay in approximately 183 years; (3) land-use changes: 92% of shoal reclamation occurred in the 1980s and 80% of waterway reclamation happened during the 1990s; Panyu District of Guangzhou city leads the table in land reclamation, Zhongshan city is second, and Zhuhai city third; the area of reclamation in the last 10 years is slightly more (1.18 times) than in the previous 10 years, in particular, there was a 1.6- and 1.8-fold increase, respectively, for the Zhongshan and Zhuhai coastal regions; at the current rate of reclamation, Tangjia Bay in Zhuhai and Jiaoyi Bay in Dongwan will vanish in approximately 25 and 70 years, respectively; the decline of the bays will cause large-scale destruction of the aquatic environment—the consequences should not be ignored. The impact of such changes on flood control and prevention, and coastal planning, are also discussed. We stress the importance of regulating and controlling the long-term development of coastal areas in the Pearl River Delta.  相似文献   

9.
The aim of this study is to predict changes in the distribution and extent of habitat forming species defined as “Priority Marine Habitats” (PMHs) in the North-East (NE) Atlantic under future scenarios of climate-induced environmental change. A Species Distribution Modelling method was used for each PMH to map the potential distribution of “most suitable” habitat. The area and percentage cover was calculated within each country׳s Exclusive Economic Zone for the baseline (2009) and the projected (2100) years. In addition, a conservation management score was calculated based on the number of PMHs that co-occur in assessment units. Overall, this study reveals the potential for movement and/or change in the extent of some PMHs across the NE Atlantic under an increased ocean temperature scenario (4 °C) by 2100. There are regional differences in the predicted changes and some countries will experience greater/different changes than others. The movement of biodiversity hotspots (where one or more PMHs occur in the same broad area) provides both opportunities and risks for conservation management that are discussed. Co-operation between neighbouring countries and marine regions will require substantial enhancement in order to provide a robust adaptive management strategy going forward.  相似文献   

10.
Natural and anthropogenic factors in coastal wetland changes are widely discussed in wetland studies. Previous literatures have demonstrated that many factors may cause wetland change and argued that the global climate change and nutrient enrichment may become the most important ones in the next 50 years. Through field investigation, with the help of remote sensing technology and geographic information system, this research discusses the wetland change in Tianjin under the great pressure of rapid economic development, population growth, and sea-level rising. These findings include: (1) the wetland area expanded from 466.50 km2 to 658.38 km2 between 1987 and 1998, but it shrank to 550.5 km2 by the year of 2006. (2) The results show that the groundwater has not been contaminated while the surface water has been polluted. (3) The questionnaire survey shows that the social environment in some specific ways impedes the protection of natural reserve. In order to achieve the harmony between human and nature, feasible countermeasures on how to keep ecological balance should be immediately taken. Consequently, natural conservation and sustainable economic development will be realized.  相似文献   

11.
The incorporation of the ecosystem approach into marine planning requires that all aspects of value associated with marine biodiversity are incorporated into the decision making process. An ecosystem services approach to valuing marine biodiversity is recognised as a framework by which economic, ecological and social values may be incorporated into the decision making process. There are sectors of the marine leisure and recreation industry (sub-aqua diving, sea angling and wildlife watching), which depend on the presence of natural marine resources in order to carry out their activity. Estimating the value of this direct use can provide an evidence base for the sustainable use of marine biodiversity when set against other competing economic interests in marine spatial planning. In the case study area of Lyme Bay, the marine leisure and recreation industry has been valued using both monetary and non-monetary methods. The results show that the leisure and recreation industry is dependent on the diversity of sites (many of which are currently unmanaged) and that the industry is of economic significance and an area which has recently been closed to trawling activity enables the protection of some of the most valuable sites but has limited benefits for protecting the full resource base upon which this local industry depends.  相似文献   

12.
Acoustic seabed classification is a useful tool for monitoring marine benthic habitats over broad-scales (>1 km2) and meso-scales (10 m2–1 km2). Its utility in this context was evaluated using two approaches: by describing natural changes in the temporal distribution of marine biotopes across the broad-scale (4 km2), and by attempting to detect specific experimentally-induced changes to kelp-dominated biotopes across the meso-scale (100 m2). For the first approach, acoustic backscatter mosaics were constructed using sidescan sonar and multibeam echosounder data collected from Church Bay (Rathlin Island, Northern Ireland) in 1999, 2008 and 2009. The mosaics were manually segmented into acoustic facies, which were ground-truthed using a drop-video camera. Biotopes were classified from the video by multivariate exploratory analysis and cross-tabulated with the acoustic facies, showing a positive correlation. These results were integrated with bathymetric data to map the distribution of seven unique biotopes in Church Bay. Kappa analysis showed the biotope distribution was highly similar between the biotope maps, possibly due to the stability of bedforms shaped by the tidal regime around Rathlin Island. The greatest biotope change in this approach was represented by seasonal and annual changes in the growth of the seagrass, Zostera marina. In the second approach, sidescan sonar data were collected before and after the removal of 100 m2 of kelp from three sites. Comparison of the data revealed no differences between the high-resolution backscatter imagery. It is concluded that acoustic seabed classification can be used to monitor change over broad- and meso-scales but not necessarily for all biotopes; its success depends on the type of acoustic system employed and the biological characteristics of the target biotope.  相似文献   

13.
Our objective was to understand how marine birds respond to oceanographic variability across the Southern Indian Ocean using data collected during an 16-day cruise (4–21 January 2003). We quantified concurrent water mass distributions, ocean productivity patterns, and seabird distributions across a heterogeneous pelagic ecosystem from subtropical to sub-Antarctic waters. We surveyed 5155 km and sighted 15,606 birds from 51 species, and used these data to investigate how seabirds respond to spatial variability in the structure and productivity of the ocean. We addressed two spatial scales: the structure of seabird communities across macro-mega scale (1000 s km) biogeographic domains, and their coarse-scale (10 s km) aggregation at hydrographic and bathymetric gradients. Both seabird density and species composition changed with latitudinal and onshore–offshore gradients in depth, water temperature, and chlorophyll-a concentration. The average seabird density increased across the subtropical convergence (STC) from 2.4 birds km−2 in subtropical waters to 23.8 birds km−2 in sub-Antarctic waters. The composition of the avifauna also differed across biogeographic domains. Prions (Pachyptila spp.) accounted for 57% of all sub-Antarctic birds, wedge-tailed shearwaters (Puffinus pacificus) accounted for 46% of all subtropical birds, and Indian Ocean yellow-nosed albatross (Thallasarche carteri) accounted for 32% of all birds in the STC. While surface feeders were the most abundant foraging guild across the study area, divers were disproportionately more numerous in the sub-Antarctic domain, and plungers were disproportionately more abundant in subtropical waters. Seabird densities were also higher within shallow shelf-slope regions, especially in sub-Antarctic waters, where large numbers of breeding seabirds concentrated. However, we did not find elevated seabird densities along the STC, suggesting that this broad frontal region is not a site of enhanced aggregation.  相似文献   

14.
《Ocean & Coastal Management》2006,49(9-10):696-705
Coral Cay Conservation, a United Kingdom-based not-for-profit organization, operates using teams of international volunteers to conduct coral reef and tropical marine resource assessments in order to provide a baseline of data to facilitate marine resource management. This modus operandi provides the resources necessary to conduct a detailed study at minimal cost to the host country partners.This paper introduces a technique of data analysis to define the conservation value of the shallow (<30 m) tropical coastal environment. All data initially undergoes multivariate analysis to define discrete benthic habitat classes using the methods described by Mumby and Harborne [Development of a systematic classification scheme of marine habitats to facilitate regional management and mapping of Caribbean coral reefs. Biological Conservation 1999;88:155–63]. Subsequent analysis of benthic and reef fish data in terms of biodiversity and reef health indices allows spatial comparison of sites of differing conservation value and the geographic delineation of areas suitable for Marine Protected Area status.  相似文献   

15.
A method to identify special and/or unique sites was developed when reviewing the zoning of the Great Barrier Reef Marine Park. Fifty-three (totalling approximately 10,445 km2) of 408 sites were identified as special or unique based on the amount, detail and nature of justification; geographic explicitness; type of information sources; number of independent sources; and national or international obligations. All but four special or unique sites increased in protection after the Zoning Plan was revised, increasing the area of no-take protection for all special or unique sites from 1614 km2 (15.4%) to 4013 km2 (38.4%).  相似文献   

16.
We observed the origin, behavior, and flux of dissolved organic carbon (DOC), dissolved organic nitrogen (DON), colored dissolved organic matter (CDOM), and dissolved inorganic nitrogen (DIN) in the subterranean estuary of a volcanic island, Jeju, Korea. The sampling of surface seawater and coastal groundwater was conducted in Hwasun Bay, Jeju, in three sampling campaigns (October 2010, January 2011, and June 2011). We observed conservative mixing of these components in this subterranean environment for a salinity range from 0 to 32. The fresh groundwater was characterized by relatively high DON, DIN, and CDOM, while the marine groundwater showed relatively high DOC. The DON and DIN fluxes through submarine groundwater discharge (SGD) in the groundwater of Hwasun Bay were estimated to be 1.3 × 105 and 2.9 × 105 mol d 1, respectively. In the seawater of Hwasun Bay, the groundwater-origin DON was almost conservative while about 91% of the groundwater-origin DIN was removed perhaps due to biological production. The DON flux from the entire Jeju was estimated to be 7.9 × 108 mol yr 1, which is comparable to some of the world's large rivers. Thus, our study highlights that DON flux through SGD is potentially important for delivery of organic nitrogen to further offshore while DIN is readily utilized by marine plankton in near-shore waters under N-limited conditions.  相似文献   

17.
Competing usage of marine space has prompted several coastal nations to implement marine spatial planning (MSP). While progressive governments promote the deployment of renewable energy technologies (RETs) in order to meet renewable energy capacity and greenhouse gas emissions reductions targets, offshore RETs become another player operating within a finite and already stressed marine environment. This paper applies the sectoral MSP process employed by Scotland to the Nova Scotia context in order to draft a MSP for the province's tidal energy sector. Applicable legislation is reviewed in order to establish the regulatory authorities with powers to plan for both the marine development and ecosystem protection agendas. The scoping process identifies suitable resource areas based on the operational parameters of commercially viable tidal current turbines (TCTs), while the sustainability appraisal identifies areas of cultural, industry, ecological, and socioeconomic constraint and exclusion. Plan option areas emanating from the applied methodology demonstrated a 238.345 km2 (98.1%) increase in suitable TCT deployment area than the marine renewable energy areas identified in Nova Scotia's Marine Renewable Energy Act which did not undertake such a methodology.  相似文献   

18.
Effective fisheries management needs to consider spatial behavior in addition to more traditional aspects of population dynamics. Acoustic telemetry has been extensively used to provide information on fish movements over different temporal and spatial scales. Here, we used a fixed-receiver array to examine the movement patterns of Labrus bergylta Ascanius 1767, a species highly targeted by the artisanal fleet of Galicia, NW Spain. Data from 25 individuals was assessed for a period of 71 days between September and November 2011 in the Galician Atlantic Islands Maritime-Terrestrial National Park. Fish were present within the monitored area more than 92% of the monitored time. The estimated size of individual home ranges, i.e. the area where fish spent most of their time, was small. The total minimum convex polygons area based on all the estimated positions was 0.133 ± 0.072 km2, whereas the home range size estimated using a 95% kernel distribution of the estimated positions was 0.091 ± 0.031 km2. The core area (50% kernel) was 0.019 ± 0.006 km2. L. bergylta exhibited different patterns of movement in the day versus the night, with 92% of the fish detected more frequently and traveling longer distances during the daytime. In addition, 76% of the fish displayed a larger home range during the day versus during the night. The linearity index was less than 0.005 for all fish suggesting random movements but within a relatively small area, and the volume of intersection index between consecutive daily home ranges was 0.75 ± 0.13, suggesting high site fidelity. The small home range and the sedentary behavior of L. bergylta highlight the potential use of small MPAs as a management tool to ensure a sustainable fishery for this important species.  相似文献   

19.
The scope of this work was to evaluate the levels of polycyclic aromatic hydrocarbons (PAHs) and their possible sources in two shallow sediment cores from an estuarine area located in the south region of Brazil, the Guaratuba Bay. The estuary is encompassed by an Environmental Protection Area (EPA) of 1306 km2, which is still considered to be pristine, despite recent urban growth. To assess levels of 14 selected PAHs in the sediments, among those listed as “priority pollutants” by the US Environmental Protection Agency, the cores were divided in several sections, followed by extraction, clean-up, fractionation and subsequent analysis using HPLC coupled to a fluorescence detector. Among the PAHs detected, phenanthrene and fluoranthene showed the highest concentrations. PAHs with more than four rings were usually present in low concentrations or were undetectable. To assist in the identification of possible sources, the ratios An/(An + Phe) and Flt/(Flt + Py) (anthracene to anthracene plus phenanthrene and fluoranthene to fluoranthene plus pyrene) and a PCA model were also used. Total concentrations of PAHs ranged between 1.5 and 3130 ng/g (mean 495) dry weight for the core collected in the inner part of the estuary, and between 78.5 and 3270 ng/g (mean 899) dry weight for the other core, collected in the outer part. Compared to values found in other studies in coastal zones along South American eastern margin, this area can be considered to range from low polluted to moderately polluted. From the data, it was also possible to conclude that there is predominance of petroleum sources, and essentially close to the more urbanised areas. Combustion sources have only minor contribution and are episodic, when compared to the latter.  相似文献   

20.
Climate models with biogeochemical components predict declines in oceanic dissolved oxygen with global warming. In coastal regimes oxygen deficits represent acute ecosystem perturbations. Here, we estimate dissolved oxygen differences across the global tropical and subtropical oceans within the oxygen minimum zone (200–700-dbar depth) between 1960–1974 (an early period with reliable data) and 1990–2008 (a recent period capturing ocean response to planetary warming). In most regions of the tropical Pacific, Atlantic, and Indian Oceans the oxygen content in the 200–700-dbar layer has declined. Furthermore, at 200 dbar, the area with O2 <70 μmol kg?1, where some large mobile macro-organisms are unable to abide, has increased by 4.5 million km2. The tropical low oxygen zones have expanded horizontally and vertically. Subsurface oxygen has decreased adjacent to most continental shelves. However, oxygen has increased in some regions in the subtropical gyres at the depths analyzed. According to literature discussed below, fishing pressure is strong in the open ocean, which may make it difficult to isolate the impact of declining oxygen on fisheries. At shallower depths we predict habitat compression will occur for hypoxia-intolerant taxa, with eventual loss of biodiversity. Should past trends in observed oxygen differences continue into the future, shifts in animal distributions and changes in ecosystem structure could accelerate.  相似文献   

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