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1.
As coastal populations expand, demands for recreational opportunities on beaches and coastal dunes grow correspondingly. Although dunes are known to be sensitive to direct human disturbance and provide irreplaceable ecosystem services (e.g. erosion control, critical habitat and nesting sites), dunes serve as campsites for large numbers of people (∼90,000 p.a.) on the ocean-exposed shores of Fraser Island, Australia. Campsites are located in the established dunes and can only be accessed with 4WD vehicles along tracks cut directly from the beach through the foredunes. Here we quantified the extent of physical damage to foredunes caused by this practice, and tested whether human-induced physical changes to foredunes translate into biological effects. Of the 124 km of ocean-exposed beaches, 122 km (98%) are open to vehicles driven on the beaches, and camping zones cover 28.7 km or 23% of the dunes. A total of 235 vehicle tracks are cut across the foredunes at an average density of eight tracks per km of beach. These tracks have effectively destroyed one-fifth (20.2%) of the dune front in camping zones, deeply incising the dune-beach interface. There is evidence of accelerated erosion and shoreline retreat centred around vehicle tracks, resulting in a “scalloping” of the shoreline. No dune vegetation remains in the tracks and the abundance of ghost crabs (Ocypode spp.) is significantly reduced compared with the abutting dunes. Because current levels of environmental change caused by dune camping may not be compatible with the sustainable use of coastal resources and conservation obligations for the island (listed as a World Heritage Area and gazetted as a National Park), restoration and mitigation interventions are critical. These will require spatial prioritisation of effort, and we present a multi-criteria ranking method, based on quantitative measures of environmental damage and ecological attributes, to objectively target rehabilitation and conservation measures. Ultimately, coastal management needs to develop and implement strategies that reconcile demands for human recreation, including beach camping, with conservation of coastal dune ecosystems.  相似文献   

2.
The Magilligan sand spit dune field is situated on the eastern mouth of Lough Foyle in County Londonderry, Northern Ireland. It is a large triangular-shaped site some 7 km by 4 km by 1.5 km wide (about 800 ha) and maintains areas, particularly in the eastern part, with slacks that regularly flood in winter. The size of the system acts as a buffer to external drivers due to the large volume of groundwater stored, the longer travel distances and lower hydraulic gradients. However, unlike many other coastal dune sites with humid dune slacks in the British Isles the sand is not wholly underlain by silt and clay, as raised beach sand and gravel deposits are in contact with the sand aquifer in some places. A preliminary water balance suggests that the majority of the discharge from the sand aquifer occurs via the underlying raised beach deposits and only a small amount discharges directly from the sand aquifer beneath the foredunes. Available water level monitoring is skewed towards the wetter end of the dune system; no significant short-term water level trends are apparent. The data also indicate that recharge regularly takes place within the sand aquifer interspersed by periods of groundwater level recession.  相似文献   

3.
Coastal dunes are increasingly at risk due to pressures deriving from global climate change, sea level rise, recreation and development. The consequences of the “coastal squeeze” in which dunes are placed, such as erosion and the loss of critical ecosystem services, are usually followed by expensive restoration and protection measures, many of which are unsuccessful. Due to the poor understanding and acknowledgement of the key attributes of coastal dunes in decision making processes, it is essential to provide scientific data on the impacts of human interference on coastal dunes so as to inform executives and guide them towards a sustainable management of the coastal zone. The aim of this study was to investigate the impact of five different levels of infrastructure development on the vegetation community structure of coastal dunes in Jeffreys Bay, South Africa. The effects of infrastructure development on dune vegetation were quantified by measuring the richness, diversity, cover, height and composition of plant species. With an increase in infrastructure development a significant decrease in dune width, average species richness and height of the plants occurred, accompanied by a shift in plant community composition. The foredunes that were backed immediately by infrastructure presented significantly greater species richness, diversity, cover and height compared with the foredunes abutted by primary dunes. This study demonstrated that coastal dunes are environments which are sensitive to varying levels of human impact. Informed and comprehensive management planning of these environments is therefore imperative for the restoration and maintenance of remnant dunes and for the conservation of undeveloped coastal dunes.  相似文献   

4.
Coastal dunes are an essential part of beach-dune systems. Dunes systems have their own intrinsic values and provide a range of goods and services, including the protection of tangible goods located on the shoreline affected by waves, storms, and sea erosion. Dunes also act as repositories of biodiversity that have their exclusive habitat in dune communities, and the aesthetic value of dune landscapes derived from unique plant communities and landforms is also of great importance. Nevertheless, dune systems on developed coasts suffered a drastic decline in geomorphological and ecological quality throughout the last century. Catalonia (Spain, NW Mediterranean Sea) is no exception, and the coastal dune systems which were present in the early 20th century have now disappeared due to urbanization. The regeneration of dune systems is of crucial importance in this context. The aim of this study is to assess the current status of dune systems in Catalonia in order to determine their future prospects based on beach characteristics, those beaches likely to host dunes being determined according to their width and sediment type. The results of our study show that nowadays most dune systems in Catalonia are not developed due to human pressure on the beaches. Only those beaches located in the natural protected areas in Roses Bay, Baix Ter Bay, the Llobregat Delta, and especially the Ebro Delta, have the right characteristics to host well-developed dune systems. That said, 30% of sandy beaches in Catalonia have a width of over 35 metres; wide enough to host well-developed dune systems if appropriate integrated beach management is applied. The methodology used in this research also provide a tool to assess which are the beaches that can host dunes on other developed shores in the Mediterranean area.  相似文献   

5.
The main aim of this paper is to present a new methodology to determine coastal susceptibility to erosion and flooding processes by means of an index-based method. The proposed indices take into account physical parameters, such as dune and beach geomorphologic characteristics, shoreline evolution, local significant wave height and relative run-up. The coastal susceptibility has been estimated by elaboration of spatial input data into a GIS environment. The method has been tested in Valdelagrana area, a sandy spit located in SW Spain. The spit includes several morpho-sedimentary environments: sandy beach, discontinuous embryo dunes and foredunes, mud flats and wide areas of vegetated salt marshes. The Northernmost sector is densely urbanized whilst the rest is part of a natural protected area belonging to the Bahía de Cádiz Natural Park. The results obtained showed how the Southern part of the spit presented a high susceptibility due to an elevated erosion rate and the presence of low and discontinuous dune ridges.  相似文献   

6.
This paper is a summary and elaboration of an earlier publication in Dutch on the compilation of a landscape-ecological map, scale 1 : 50 000, of the Dutch coast. It is argued that such an integrated map is the best basis for the conservation and management of the coastal dunes and salt marshes. It may be combined with local more detailed vegetation maps, some examples of which are mentioned in the context of management. The Dutch North Sea coast is a ca. 350 km long chain of sandy beaches and sand dunes, from only 100 m to more than 10 km wide. On sheltered stretches of dune coasts along estuaries in the Southwest and on the Wadden Sea islands, salt marshes have developed. The small-scale gradient structure of the beach-dune-salt marsh complex is emphasized.  相似文献   

7.
This study examined the relative impacts of different human activities and natural resource protections on the spatial distribution of beach vegetation and related habitat features (wrack, dune succession) in New Jersey (USA). Field surveys of the 209-km shoreline categorized beach segments according to vegetation cover classes, human activities, protection measures (exclosures, beach management plans, access restrictions) and ownership status (federal, state, etc.). A partition model (classification tree) was used to confirm the relative dominance hierarchy of human actions on the distribution of beach vegetation observed, and quantitative comparisons of dominant activities were conducted using vegetation data collected on 218 transects. The spatial extent of beach vegetation was found to be severely restricted by human activities when unconstrained by resource protections. The greatest reductions were found to result from mechanical raking (?99 %), scraping (?91 %) and all-year recreational ORV use (?86 %), which were dominant on nearly 70 % of the state shoreline. Beaches containing larger areas of vegetation (>5 m) were concentrated in areas with resource protections of various kinds (99 %), and on federal or other public parklands (68 %). Exclosures resulted in the greatest coverage of vegetation (48 % of beach surface) compared to public access restricted areas (41 %), beach management plans (31 %), government-only ORV use (31 %), and off-season recreational ORVs (15 %). Greater protection and recovery of beach vegetation and habitat is needed for species conservation and erosion protection in New Jersey and other coastal environments where these activities occur.  相似文献   

8.
The rationale and methods of construction of foredunes in The Netherlands and New Jersey, USA are identified and used to explain their genesis, locations, mobility, internal and external characteristics and temporal scales of evolution. Dunes are then ranked according to the degree they are modified by human processes. The lower level of protection required of foredunes in New Jersey and the greater amount of modification by municipal managers and shorefront residents results in smaller dunes and greater variety of sizes, shapes, methods of construction and alterations. As a result, humans are considered intrinsic agents in evolution of dune landforms and landscapes. Higher, wider, better vegetated foredunes occur in The Netherlands due to greater frequency of onshore winds and greater emphasis on sea defence at the national level. Natural processes play a greater role in the evolution of landforms. Human actions are considered extrinsic at this scale but intrinsic at the scale of landscapes. The change in foredunes from natural features to artifacts reveals the significance of humans in the modification of coastal landforms and reflects the changing perception of the role of these landforms in the coastal landscape.  相似文献   

9.
In 1990, the Government and Parliament of the Netherlands decided on a new national policy for coastal defence. To ensure the enduring safety of the low-lying polders as well as the sustainable preservation of the coastal dunes, it was decided to maintain the coastline in its 1990 position. The main method for coastline preservation in the Netherlands is beach nourishment. Since 1991, approximately 7 million m3 of sand is added to the Dutch beaches annually. From an evaluation study of sand nourishment projects it is concluded that nourishment is an effective and efficient method to preserve the coastline. The evaluation study also proves that nourishment projects should be ‘tailor-made’, taking the local morphological and hydraulic conditions into account. The first results of an experimental shoreface nourishment are discussed. The choice for nourishment as the principal method to combat erosion is well in line with the intention to restore the natural dynamics of the dune-coast in the Netherlands. The key probably is a less strict policy with regard to the maintenance of the foredunes. Plans for the development of typical coastal features such as slufters*, wash-overs, blow-outs and mobile dunes are currently under discussion. A slufter is a breakthrough in the first dune-ridge whereby the sea invades former dune slacks or beach plains situated behind the duneridge. In this way a tidal marsh is formed within the dune zone.  相似文献   

10.
Machair is a highly specialised and complex sand dune habitat confined globally to the west coasts of Ireland and Scotland. Irish machair is designated as a priority habitat under the EU Habitats Directive, with the habitat coverage restricted to the machair grassland. The main goals of the study were to describe the Acari fauna inhabiting the Irish machair and to determine the uniqueness of its mite communities in the context of habitat protection. Ten Irish machair sites were selected and samples were taken from the machair grassland and from two types of dunes within the wider machair system: shifting dunes (foredunes) occurring at the beach and stable (fixed) dunes located in the transition zone to the inland grassland flat areas. One hundred and eleven mite taxa were recovered. The most widespread was Scutovertex cf arenocolus Pfingstl et al. 2009, a halophilous species that has been found in the epilittoral zone of Baltic and European Atlantic coasts. The genus Autogneta Hull 1916 (Oribatida: Oppiidae) and the oribatid species Hermaniella granulata (Nicolet 1855) were recorded for the first time for Ireland. Peloptulus cf gibbus Mihelčič 1957, may also be a new record. Multivariate analysis showed that community composition varied between the areas sampled in the machair systems and that in the machair grassland, an Annex I priority habitat in Ireland, was especially different from both dune types sampled. The assemblages also varied significantly between the different sites sampled in the study.  相似文献   

11.
The varied and very dynamic landscape with a high biological diversity is a distinctive feature of the Curonian spit at the regional scale. Throughout the 20th century the main morphodynamic trend in the littoral of the Curonian spit was shoreline grading on the lagoon side, whereas on the marine side the increasing erosion at the foot of the spit, and increasing accretion at the head of the spit prevailed. The results of a discriminant analysis (Wilkes’ λ = 0.001626 and F = 29.267 when p < 0.001) show that sites with prevailing erosion, accretion and sediment input from the drifting dunes form regular inter-related spatial structures in the littoral with distinctive resulting discontinuities of the sediment drift along the lagoon coast. Dune littoral cells are characterized by Aeolian sediment input and distribution ‘down-drift’, (usually northwards) from the source. The most likely changes in the current development trends of the lagoon shore zone of the Curonian spit are related to expected climate changes and further slowing down of the dune drift. The probability of storms and ice-drift events, and their impact on coasts is expected to increase as a result of climate change. The dune advance will gradually slow down, and with it, the sand input to the coastal zone will decline. In this paper, we define integrated shoreline management as a system of long-term shoreline management measures, which is based on a littoral cell approach and aimed at harmonizing human activity in the coastal zone with the natural development of the shoreline. We propose an integrated management program for the lagoon shoreline of the Curonian spit, which is site-specific for each littoral cell as a coastal management unit. Drifting dunes and seaside beaches are the natural amenities, which are best known and best appreciated on the Curonian spit by 49% of the respondents representing the total Lithuanian population. A responsible tourism development should be considered as the key means for proper appreciation of the drifting dunes and natural coasts by society, which means to acknowledge and cherish the aesthetic and conservation values of dune and coastal landscapes of the Curonian spit as a World Heritage Site. There are at least two pre-conditions for this: (1) to provide visitors with sufficient information about diverse values and functions of the Curonian dunes and coasts within a broader regional and global heritage conservation context; (2) to enable tourists to enjoy the most impressive dune and coastal landscapes at close range. In this paper we propose to encourage active dune tourism, to reintroduce grazing into the Curonian dune areas, to restore and to preserve the most impressive landscapes of the highest white drifting dunes by bringing the blown out sand from the leeward foot of the dunes back to the crest artificially.  相似文献   

12.
Although most UK sand dune systems are now fossilized, with little mobility and reducing amounts of bare sand, they support important populations and assemblages of terrestrial invertebrates. Offering open conditions, warm substrates and a range of habitats and habitat structures, they have become increasingly significant as other coastal habitats have been lost. In Wales, 680 Red Data Book and Nationally Scarce species have been recorded from dunes. 109 species in the UK are restricted to dunes, and in Wales there are an additional 145 species confined to dunes and 208 species strongly associated with dunes. Of these, 172 species are dependent upon bare and sparsely-vegetated sand, in grey dunes and early-successional dune grassland, at some stage of their life cycle, rising to 292 species if those associated with the strandline, foredunes, yellow dunes and pioneer dune slacks are included, equating to 63% of the 462 dune species. Bees and wasps are particularly well represented, with 278 species (68% of the Welsh fauna) recorded on Welsh dunes, including 17 obligates and 44 species with a strong dependence, 52 of which are associated with bare and sparsely-vegetated sand. Key to maintaining invertebrate populations on UK dunes is the provision of bare sand but in Wales, bare sand accounts for only 1.7% of the total sand dune resource. As a more appropriate bare sand threshold is likely to range between 10 and 30%, radical action is required to re-mobilize at least the key sand dune systems.  相似文献   

13.
14.
Geomorphological and sedimentological studies were carried out along the Garigliano and Elis littorals with the aim to highlight if similar geoenvironmental features are controlled by same coastal processes. Actually, both sites are in Mediterranean climate regions very far each other, modeled by western winds and storms, characterized by wide sandy coastal dunes parallel to the present shoreline, with abundant pumices, and locally anthropized. The Garigliano littoral is characterized by Holocene dune and Pleistocene aeolian deposits. The beach is bounded landwards by a dune system emplaced during the Holocene. Geoarchaeological surveys highlighted the presence of a Roman road which cut the dune, with age older than Graeco-Roman Period. Since the end of the 1950’s, strong littoral retreat affected the beach-dune system, partly due to human activity. The coastland of Elis is characterized by Quaternary marine deposits. Three significant morphogenetic phases occurred during the Holocene. During the last phase, from Graeco-Roman Period to current, shoreline retreat and deposition of aeolian sands occurred. Geoarchaeological evidences suggest that this phase is related to a sea-level lowstand followed by a slow sea-level rise up to the present position, and by humid-temperate climate. Geomorphological surveys of the dunes of Garigliano and Elis, each other compared, suggest that the main phases of their development are related to the effects of climatic conditions, sea-level changes, and secondly to the recent anthropization. The coarse pumices found on both beaches of Campania and Peloponnese regions show the same mineralogical and petrographic features, so we assumed that they likely originated from the Aeolian Arc, southern Italy, which have same composition. These pumices reached the studied coasts by flotation, under the influence of winds and marine surface currents from the southwest-southeast and northwest-west respectively, participating to local coastal processes and representing a good geoindicator of long-distance drift. Precisely for these morphologically converging aspects, such distant sites have been selected and compared.  相似文献   

15.
This paper is based on literature-based studies, as well as material collected by the author over more than 30 years on the shores of the Southeast Baltic Sea. In order to protect roads running along the shoreline from East Prussia to Königsberg, local shore reinforcement works commenced in the fifteenth century, although some individual attempts had been made before. In 1684, M. Ch. Hartknoch theoretically substantiated the necessity for, and methods of, shore reinforcement. The state of the shores deteriorated considerably during the Seven Years War (1756–1763), when woodlands growing along the shores were completely destroyed; hence, nearly 100 km length of the coast of the Kur?i? Nerija (Curonian) sand spit was left without any vegetation. Aeolian sand buried as many as fourteen settlements. This situation forced the authorities to organise maintenance of the coast and the dunes at the governmental level, and to start the formation of an uninterrupted dune ridge. The second half of the nineteenth century and the first half of the twentieth century are notable for the extensive construction of new ports. Along the shores running from the Sambian Peninsula to the Gulf of Riga, eight port engineering structures had been constructed with the intervals of approximately 26 km between the ports of Klaip?da and Liepaja, and every 13 km between Palanga and Pape. Shore management measures were being implemented simultaneously, thus ensuring the functioning of the above-mentioned coastal protection structures and the reduction of impacts upon the shores. In the second half of the twentieth century, ports were dredged and developed significantly. Their entrance channels reduced the long-shore sediment transport. Moreover, total sand reserves in the shore zone also diminished. The processes of erosion of the beaches and the dune ridge made it necessary to actively reinforce the shore. A number of countries passed legal acts governing the protection and use of the shore zone. At the turn of the twenty-first century, the incompatibility of such priorities in human activities as sea transport and recreation with nature protection has become evident. The conflict of interests in the Kur?i? Nerija National Park, the port of Klaip?da, and the resort of Palanga serve as good examples of such incompatibility. The conclusion that can be drawn that in twenty-first century is that the priorities in general coastal management should be as follows: harmonisation of interests among the states and individual fields of activities, as well as measures aimed at neutralisation of negative natural trends (higher frequency of storms, global rise of water level, etc.). The protective beach dune ridge will further play the role of efficient means for reducing shore erosion.  相似文献   

16.
A detailed and multidisciplinary study of physical and biotic factors of a coastal sector of southern Italy, the Pineta della foce del Garigliano SCI (Site of Community Importance) area, has been carried out in the frame of the European research project LIFE + Nature & Biodiversity PROVIDUNE. We evaluated the degree of dunes vulnerability (Dune Vulnerability Index, DVI) and sustainable anthropogenic load (carrying capacity) of the emerged beach of the study area, which is largely affected by shoreline retreat and degradation of dune habitat. The values of about 0.6 of the DVI in the two key sectors of the study area suggest a high level of vulnerability of beach/dune system due to both natural and human factors. The partial vulnerability index related to the geomorphological condition exhibits the highest values, as a consequence of a coastal system largely affected by recent and present-day beach erosion and severe hydrodynamics processes. Several inadequate human practises have been recognized in the study area whose impact appears to be an important factor in controlling the reduction of the beach-dune system resilience. Integrated analysis of DVI and carrying capacity suggests that the northern and central sectors of the study area have a high level of dune vulnerability due to hydrodynamic and geomorphological factors whereas the human impact can be considered relatively less important. The southern sector of the study area is featured by a well-developed infrastructure system, which is able to assure a sustainable beach occupation. Nevertheless, significant interventions such as dune replacement by permanent or ephemeral infrastructures, uncontrolled pedestrian or vehicular access and inappropriate use of mechanical beach cleaning have been recognized in this sector of the beach. These long-lasting impacts have promoted the dismantling of large sector of the dune habitats. Obtained results allowed identifying the critical area where appropriate actions can be performed for the mitigation of impacts, the conservation of dune habitats and their sustainable use.  相似文献   

17.
Coastal dunes are delicate systems that are under threat from a variety of human and natural influences. Groundwater modelling can provide a better understanding of how these systems operate and can be a useful tool towards the effective management of a coastal dune system, e.g. by identifying strategically important locations for flora and fauna and guiding the planning of management operations through predicting impacts from climatic change, sea level rise and land use management. Most dune systems are small, typically of the size 10–100 km2, compared with inland groundwater systems. Applying conventional groundwater modelling approaches to these small systems presents a number of challenges due to the local scale of the system and the fact that the system boundaries (sea, drains, ponds etc.) are close to the main body of the aquifer. In this paper, two case studies will be presented using different modelling approaches to understand the groundwater balance in two dune systems in the UK. The studies demonstrate that, although conventional hydraulic models can describe the general system behaviour, a fuller understanding of the recharge mechanisms and system boundaries is needed to represent adequately system dynamics of small groundwater systems.  相似文献   

18.
Wissant Bay is a picturesque and highly frequented French coastal resort comprising beaches, dunes, marshes, and bold capes facing the Dover Strait. Situated at the southern approaches to the North Sea, the 8 km-long bay has, arguably, the most rapidly eroding shoreline in metropolitan France. Retreat has largely affected much of the bay shoreline west of Wissant town, with parts of this sector having lost up to 250 m in the last 50 years, whereas a much smaller sector east of the town is a zone of accretion. Various dune, beach and nearshore morphodynamic studies conducted over the last decade have identified chronic sand bleeding from the western sector and longshore transport to the east, within a framework of what appears to be an ongoing shoreline rotation process within a dominant longshore sediment transport cell between the headland of Cape Gris Nez to the west and the bold chalk cliffs of Cape Blanc Nez to the east. Retreat of the narrowing beach-dune barrier poses a threat in the coming years, as there is a likelihood of it being breached by storms. The seawall protecting Wissant town has also been repeatedly damaged since 2000 due to the chronic sand deficit. These changes involve interactions between a nearshore sand bank, a complex macrotidal beach comprising multiple subtidal to intertidal bars and troughs subject to strong longshore sand transport especially during storms, and aeolian dunes. The nearshore bank acts as a dissipater of incident storm wave energy and as a sand source for the multi-barred beaches and dunes, and has been strongly impacted by past massive aggregate extraction. The bank is, in turn, part of a larger system of mobile banks reworked by storms and tidal currents within the framework of a sand circulation system between the eastern English Channel and the southern North Sea. The aim of this work is to confront knowledge acquired on the morphodynamics of the bay with an engineering plan proposed to counter erosion and reestablish shoreline stability. The plan is based essentially on the creation of an ‘equilibrium’ beach profile, capable of withstanding storms, comprising an enlarged upper beach berm, and constructed through beach nourishment from a nearshore source located 20 km east of Wissant Bay. The plan has not been implemented because of cost. Even if it were to be implemented, its efficiency seems very doubtful because the beach profile simulations on which it is based neglect the complex multi-barred morphology and the overwhelming dominant longshore transport over bars during storms. The plan is also geared towards resolving a local problem of erosion that is embedded in the larger and rather complex spatiotemporal morphodynamics and sediment transport mechanisms evoked above. Wissant Bay is emblematic of the problems of erosion facing many communes in France, and elsewhere. The fight against shoreline erosion generally starts with the commonly insurmountable hurdle of fund-raising for costly engineering proposals that are not always based on a clear grasp of the embedded scales of change affecting the coast.  相似文献   

19.
The aims of this study are to review the current situation of the Israeli Mediterranean coastal sand dunes, to examine the causes for this situation, and to propose options for future conservation and management of the protected dune areas based on ecological, environmental, landscape and recreational demands and interests. The coastal dunes of Israel are characterized by diverse plant communities, with 173 plant species occurring on sand (8.2% of the total flora of Israel) including many endemic species (26% of all endemic species in Israel). Most of the species are annuals. The importance of the coastal strip as a centre of floral and faunal speciation is also manifested in the existing sand-bound animals. However, many species are rare. This is mainly due to the extensive industrial and urban development along the coastal plain and the direct and indirect destruction of the remaining open dune areas by tourism, recreation and sand mining. Only ca. 17% of the Israeli coastal dunes are still of good or reasonable ecological value, while < 5% of this area has been designated as protected area. Management policies differ from place to place and depend on local objectives. These objectives derive mainly from the knowledge and data that exist for each location, and its statutory status. Since 1995 several projects, which aim to develop integrated management tools for nature conservation and recreation uses for all coastal sand dunes in Israel have been conducted. These projects are summarized in the present paper.  相似文献   

20.
On June 6, 2000, the Merchant Vessel River Princess – dead weight 114,645 tonnes and 261 m in length, grounded on the beach off the Candolim-Sinquerim coast, Goa, India, spilling some 40 tonnes of oil. In the past 10 years it has settled some 10 m into the sea bed and taken in circa 40,000 tonnes of sand. Until the ‘60’s the Goan economy centered on agriculture and fishing with very low key recreation. Over the last three decades it has become heavily reliant upon recreation, with 13 % of GDP arising from this sector. Nine million cubic metres of littoral drift occurs off this beach per annum, with the longshore current broken by rips into a series of circulating cells. The vessel acts as a massive groin so much so that downdrift, erosion of approximately 5 to 10 m/annum (dependent on the monsoon strength) is occurring at the Taj hotel site. Satellite imagery has shown that some 0.13 km2 beach loss has occurred since 2001. Downdrift, the beach is circa 20 m wide compared to updrift areas where it exceeds 100 m. Embryo tombola growth has now commenced between shore and ship. In addition to this, the dune system is now seriously out of equilibrium and sand bags, geotextiles etc. are currently in use to combat dune foot erosion. Questionnaires (n?=?111) showed that 37 % of beach users ranked erosion as the top coastal problem. Sixty seven percent of beach users rated scenery as the most important quality of a beach and due to the grounded ship, >60 % rated the scenery as below average, as well as viewing the ship as a source of danger for swimming purposes.  相似文献   

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