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1.
The Sands of Forvie, National Nature Reserve, Scotland is a complex coastal sand dune system which is associated with the dynamic estuary of the River Ythan. The dune system has developed over more than 5000 years. The south partis a peninsula of dunes, sandhills, sand arcs, erosion and deflation surfaces. The north part is superimposed on a rock plateau with a cliff coastline. This plateau is covered in glacial deposits and is essentially an upland heath landscape. Some of the best examples of large active parabolic dunes in Britain are found in North Forvie. The sequence of geomorphic development is described. As a nature reserve with a rich ecology it has been managed for conservational purposes since 1960s. As such it is an excellent case study of how conservational management has changed to become more flexible and more aware of the importance of dynamic processes.  相似文献   

2.
In coastal foredunes marram grass (Ammophila arenaria) is used to stabilize windblown sand. The development of traditionally plantedAmmophila into a more natural foredune vegetation may take 5 – 10 yr. For economic reasons, traditional planting may be replaced by alternative techniques such as planting seeds or disk-harrowing rhizome fragments. In this paper, we compare the initial vegetation development of traditionally planted stands with stands established from seeds and from rhizomes. The experiments were conducted on an artificial foredune originating from dredged sea sand. The total experimental area covered more than 100 ha and the vegetation development was studied for 6 yr. The data were analysed bya priori grouping of plant species according to their ecology, as well as by Principal Components Analysis (PCA) and Redundancy Analysis (RA) of the percentage ground cover per plant species. Comparing ecological groups of plants showed that all planting methods delivered equal numbers of plant species that are indicative for coastal dunes. PCA and RA showed that methods based on the use of rhizome material resulted in a higher percentage cover of clonal perennials (Calammophila baltica, Festuca rubra ssp.arenaria, Carex arenaria andCirsium arvense) than the traditionally planted stands and the stands obtained from seeds. The latter two were characterized by the dominance of annuals, bi-annuals and (mostly nonrhizomatous) perennials. Initially, the rates of succession were highest in the stands obtained from rhizomes. However, after 3 – 6 yr there were no differences between the various stands. During the first four years, the percentage cover by rhizomatous foredune plants developed faster than that of annuals, bi-annuals and perennials. After 6 yr, the latter contributed almost as much to the percentage cover as the clonal species. Nomenclature: van der Meijden et al. (1990) for plant species. The plant species were classified into ecological groups according to van der Meijden et al. (1991) and Mennema et al. (1980).  相似文献   

3.
In coastal foredunes marram grass (Ammophila arenaria) is used to stabilize windblown sand. The development of traditionally plantedAmmophila into a more natural foredune vegetation may take 5–10 yr. For economic reasons, traditional planting may be replaced by alternative techniques such as planting seeds or disk-harrowing rhizome fragments. In this paper, we compare the initial vegetation development of traditionally planted stands with stands established from seeds and from rhizomes. The experiments were conducted on an artificial foredune originating from dredged sea sand. The total experimental area covered more than 100 ha and the vegetation development was studied for 6 yr. The data were analysed bya priori grouping of plant species according to their ecology, as well as by Principal Components Analysis (PCA) and Redundancy Analysis (RA) of the percentage ground cover per plant species. Comparing ecological groups of plants showed that all planting methods delivered equal numbers of plant species that are indicative for coastal dunes. PCA and RA showed that methods based on the use of rhizome material resulted in a higher percentage cover of clonal perennials (Calammophila baltica, Festuca rubra ssp.arenaria, Carex arenaria andCirsium arvense) than the traditionally planted stands and the stands obtained from seeds. The latter two were characterized by the dominance of annuals, bi-annuals and (mostly nonrhizomatous) perennials. Initially, the rates of succession were highest in the stands obtained from rhizomes. However, after 3–6 yr there were no differences between the various stands. During the first four years, the percentage cover by rhizomatous foredune plants developed faster than that of annuals, bi-annuals and perennials. After 6 yr, the latter contributed almost as much to the percentage cover as the clonal species.  相似文献   

4.
To improve the present national and local sustainable planning capability for the coastal zone a GI application for the Italian Coastal Susceptibility Assessment was planned within an institutional agreement between ENEA and the Land Defence Service of the Italian Ministry of Environment. Taking into account previous European actions a suitable methodology to assess, in a quantitative way, the susceptibility of beaches to be eroded has been set up. The methodology balances the coastline trend as evaluated for a defined time period with the present coastal areas morphology and land use, this in order to derive a value that expresses the evolutionary process in terms of probability of the loss of goods within the ‘Homogeneous Coastal Tracts’. The trend in the movement of the sea-land line has been used asgeo-indicator of a complex dynamic balance that refers both to marine and inland systems, and a vector GI application was built and locally applied in southern Italian coastal areas. The present shoreline position and some other information describing the intrinsic beach morphologies, and having significance for the coastal erosion hazard assessment, have been derived from the national 1∶10.000 ortho-images of the National Cartographic Reference System provided by the Italian Ministry of Environment. The illustrated GI application— CoSTAT—keeps the nominal scale of all data collected or produced. In this analysis the coastal dune presence is analysed as factor limiting coastal erosion susceptibility. Applying a matrix calculation a quantitative evaluation of erosion susceptibility degree was achieved and plans were made to develop new information for a suitable use of Italian coastal areas. The work describes the methodology, the conceptual frame-work and the results of a local application.  相似文献   

5.
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   

6.
The planning and management of coastal sites in Catalonia has been mainly concerned with rendering beaches functional for mass frequentation. This has caused serious problems for the beaches, including the alteration of dune formation processes and the destruction of beach vegetation and habitats. Municipal capacity to plan and manage beaches is theoretically very limited and relegated to the design of plans related to the maintenance of facilities for beach users. Nonetheless, a singular experience, led by a local council in the metropolitan area of Barcelona demonstrates the crucial role that a local administration can play in achieving a balance between habitat preservation and social use based on sustainable coastal management objectives, in spite of a restrictive legislation.  相似文献   

7.
Marinas are usually located in coastal waters, but can also be found in lakes and rivers. Due to the activities that take place in marinas various contaminants are discharged. Specific measures have to be taken in order to keep the marina environment clean and healthy. Experiences from developed countries have shown that the most effective way to reduce pollution in marinas is the implementation of waste management programs. To this end, ‘Best Waste Management Programs’ (BWMPs) have been employed in the USA and other countries. However, in developing countries lack of available financial resources and unawareness of the concept of clean marinas may hinder the activities towards the application of BWMPs. The aim of this study is to address BWMPs in general and explain waste sources and disposal methods for marinas and yachting activities. The Kusadasi Setur marina in Turkey is investigated particularly as an example of a marina in a developing country and management measures taken in this marina are evaluated. The various kinds of waste generated in the marina are described and preventive measures against pollution taken in the marina are reviewed. Finally the importance of management programs towards the mitigation of pollution problems is emphasized.  相似文献   

8.
Coastal erosion poses serious threat to life and properties along Ghana??s coast. This is because major industries, urban settlements, recreational facilities, heritage and conservation sites are located few metres from the coast. In spite of this threat, management strategies, both past and present, remain an ??ad hoc?? and site specific. Limited attention has been given to large scale assessment and investigation to detect the rate of coastal recession and the size of land lost to the sea to inform integrated management plan and to formulate sustainable management strategies to deal with the problem. This paper provides large scale assessment of coastal recession in Ghana through field investigation, applied coastal geomorphology and GIS techniques to selected case study areas. The assessment covered 203?km out of the 540?km coastline of Ghana. Results of the assessment indicate that coastal erosion is very substantial and wide spread along the coast, but the rate of recession varies across the entire coastline. Significant amounts of losses of settlements have been experienced in some localities in the eastern coast (Keta and Ada) and the central coast (Accra, Shama and Sekondi-Takoradi). In some areas, coastal defences have been built to reduce the impacts, yet many areas are still very vulnerable. Interestingly, the paper identified that the high rates of retreat recorded in many areas have yet to cause major risks in some local communities because of the presence of a buffer of largely undeveloped land that has existed historically between the shoreline and the developments. However, recent increase in coastal tourism in Ghana has led to ??scramble?? for purchase of these buffer lands for development, which increase the risk. Ghana has the opportunity to use education and land use planning to keep the coastline clear of major developments and avoid the temptation of engaging in costly cycle of development-risk-defence experienced in many countries including the UK and the Netherlands. The paper recommends that Ghana should adopt the UK SMP, which has progressively moved away from the traditional re-active and parochial approaches of providing localised hard-engineered coastal defence work to solve what was perceived to be a local problem, to a more pro-active and holistic approach that take full account of coastal dynamics, interrelationships of coastal systems, knock-on effects, environment concerns and developments at the backshore.  相似文献   

9.
The coastline near the southern tip of Africa is characterized by large mobile dunes that are driven along wide beaches by strong winds throughout the year. This results in the blockage of the river mouths causing severe flooding of the low-lying farmland of the Agulhas Plain during the rainy winter season. Large parts of the driftsands were stabilized with the European dune pioneer species Marram grass (Ammophila arenaria), which has proved highly invasive along the North American west coast. In order to establish the potential invasiveness ofA. arenaria in South African coastal dune systems and its role in the succession of a large stabilization area, studies were carried out on De Mond Nature Reverve. Using aerial photos, maps and planting records, the vegetation of sites of various ages were sampled. By means of this chronosequence of stands, there is clear evidence that succession takes place at De Mond. Four communities are distinguished, varying from recent plantings ofA. arenaria to mature dune thicket or dune fynbos (heath) vegetation. These relate to four different stages of succession,A. arenaria occurring in reduced abundance in the older communities. After 50 years, formerA. arenaria areas are usually covered by dense dune scrub and in some places even in asteraceous dune fynbos. Succession is most rapid in sheltered, moist dune slacks, butA. arenaria remains vigorous in conditions favourable for its growht, i.e. on exposed, steep dune slopes with strong sand movement.A. arenaria does not appear to spread unaidedly at De Mond and has been successfully used for temporary dune stabilization.  相似文献   

10.
我国自然保护区有效管理评价指标研究   总被引:1,自引:0,他引:1  
本文根据我国自然保护区建设速度较快但管理水平较低的现状,在多年调查研究的基础上,提出制定自然保护区有效管理评价标准的必要性,并详细阐述了在保护区管理条件、管理措施、科研基础和管理成效等四个方面的评价内容,提出13项评价指标,进而作了详细的评分等级划分,提出一套评价全国自然保护区管理质量的指标体系,为全国自然保护区管理的监督检查提供了一套简便适用、易于操作的评判标准。  相似文献   

11.
A significant proportion of the fishing population comprises small-scale fishermen and many studies illustrate that these people are exploited by middlemen in the process of fish marketing combined with money lending. The negative dependency gives rise to poverty and triggers indiscriminate fish catch that threatens fishery resources depletion. This article explores the root causes of failures in resource-led development from the viewpoint of coastal resource conservation. The study presents a case study of Chilika lagoon, India and focuses on the interaction between small-scale fishermen and middlemen. The findings reveal that most of the small-scale fishermen have been exploited by specific middlemen and the underlying causes of the present fish marketing structure stem from (i) indebtedness and (ii) the unstable situation because of perpetual conflicts over fishery resources among the fishers across Chilika lagoon. Based on these observations, this article presents some recommendations on fishery resource conservation from the perspective of a fish marketing structure.
Rajib ShawEmail:
  相似文献   

12.
本文在对我国10多个省(自治区)2o多个自然保护区的实际调查和全国资料的统计分析基础上,从我国自然保护区的管理体制、管理机构建设、资源的保护与适度开发利用、科学研究与宣传教育等方面,全面分析了我国自然保护区有效管理的现状,总结了取得的成绩和存在的问题,并针对存在的主要问题,提出了相应的对策与建议。  相似文献   

13.
This article presents a system dynamics (SD) method to examine the problem of forest degradation. The model developed takes a system-oriented view of forest management, embracing both social and biophysical factors affecting deforestation. Social factors examined are socio-economic variables or elements that influence behaviour and decision-making choices at the household level. Biophysical factors are four sub-components that are considered major land uses namely, the paddy field component, rattan plantations, coffee plantations and forest stands. The model was applied in a case study located in Pasir District of East Kalimantan, Indonesia. The site covers an area that includes a protected forest and a privately allocated timber license concession. Three village communities are examined in the case study. The SD model developed was applied to the case study focusing on three management policies or scenarios, which are based on access rights to the forest resources within the study area. Specifically, the property arrangements examined in each scenario are: Policy 1 – status quo (i.e. continue present property rights arrangements); Policy 2 – local communities manage the forest exclusively; and Policy 3 – collaborative management involving both local communities and a private company. Results from the model show that the third policy is the most viable option, and also lead to a win–win solution.  相似文献   

14.
This paper reviews some of the literature and guidance provided for businesses considering responses to the environmental aspects and impacts of their tourist activities. It concentrates on the role of destinations and stakeholders within the destination cooperating and networking to improve environmental performance and on generating a ‘green’ image. In order to move towards a type of tourism consistent with sustainable development (sustainable tourism), it is argued that we need to see enhanced management of a destination, creating opportunities for networking and cooperation between, in particular, service providers. In a case study of Lillehammer, Norway, three projects negotiated, developed and delivered by service providers in the area are examined. These projects looked at hotel management, transport and aesthetics. Success factors are identified, including the involvement of stakeholders, the development of locally orientated codes of conduct, the role and participation of local authorities and the importance of leadership. Findings add to the body of practical help in moving destinations towards sustainable tourism.  相似文献   

15.
In order to provide a background picture of the water quality of the Egyptian Red Sea a number of hydrological and chemical parameters have been measured bimonthly in 2000. Few data are available on this area, which is apparently subjected to an increasing human impact due to recreational (swimming and diving), industrial (mainly phosphate shipping and industry) and fishing/harbor activities. The results of the present study indicate that changes in the salinity and pH were not significant with highly oxygenated seawaters. The levels of suspended solids (as total suspended matter, TSM) and chlorophyll-a (Chl-a) were generally low and showed an homogeneous distribution in the study region. The ratio of chlorophyll-a to total suspended matter concentrations increased between November and March and decreased from May to September. Chlorophyll-a was significantly correlated with transparency and total suspended matter concentrations in July, September and November. Nitrogen, phosphorus and reactive silicate concentrations were generally low, and allowed classifying the Egyptian Red Sea coastal water as oligotrophic to mesotrophic. The middle region of the study area, which was located between Safaga and Qusair displayed relatively high phosphate contents when compared with other coastal areas. The high values of N:P ratios indicate that PO 4 -P is the limiting factor for phytoplankton growth in the Red Sea coastal waters, with the possible exception of the middle region. Significant relationships were found between chlorophyll-a concentrations and nutrient levels in different sampling periods. Spatial distribution patterns of the studied variables revealed that productivity of the Red Sea coastal waters is mostly controlled by phosphate concentrations, salinity, temperature and dissolved oxygen.  相似文献   

16.
This study examines the impact of flooding on land of high conservation value located along part of the southern shoreline of the River Clyde Estuary in western Scotland. This paper hypothesizes that, over the next 50 years, the frequency and extent of coastal flooding will increase due to the gradual effect of global warming and the consequent rise in sea-level and increase in storminess. It is argued that because of the great cost of constructing new flood defence systems it will not be possible to protect all land areas to an equal extent from flooding. A means of ranking different land use will be necessary so that society can make a rational judgement concerning which sections of coastline will be worth protecting. This study provides a methodology that combines an objective ranking of conservation areas using non-economic indicators with a GIS model of flood potential, and permits accurate forecasts of flood losses to conservation areas of different ecological value. The conservation case study used in this paper proposes the use of an ecological weighting value based on five ecological variables each of 10 categories. Tables and maps identify the sites that have been highlighted as consisting of the most ‘valuable’ conservation sites. The methodology makes extensive use of geographical information systems (GIS) to model the predicted areas of flooding and to calculate conservation weighting values of the land areas.  相似文献   

17.
This study examines the impact of flooding on land of high conservation value located along part of the southern shoreline of the River Clyde Estuary in western Scotland. This paper hypothesizes that, over the next 50 years, the frequency and extent of coastal flooding will increase due to the gradual effect of global warming and the consequent rise in sea-level and increase in storminess. It is argued that because of the great cost of constructing new flood defence systems it will not be possible to protect all land areas to an equal extent from flooding. A means of ranking different land use will be necessary so that society can make a rational judgement concerning which sections of coastline will be worth protecting. This study provides a methodology that combines an objective ranking of conservation areas using non-economic indicators with a GIS model of flood potential, and permits accurate forecasts of flood losses to conservation areas of different ecological value. The conservation case study used in this paper proposes the use of an ecological weighting value based on five ecological variables each of 10 categories. Tables and maps identify the sites that have been highlighted as consisting of the most ‘valuable’ conservation sites. The methodology makes extensive use of geographical information systems (GIS) to model the predicted areas of flooding and to calculate conservation weighting values of the land areas.  相似文献   

18.
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   

19.
Cities (“urban superorganisms”) exhibit metabolic processes. Disturbance of these processes results from the high throughput of the socioeconomic system as a result of the flow of resources between it and its surroundings. Based on systematic ecology and emergy synthesis, we developed an emergy-based indicator system for evaluating urban metabolic factors (flux, structures, intensity, efficiency, and density), and evaluated the status of Beijing's environment and economic development by diagramming, accounting for, and analyzing the material, energy, and monetary flows within Beijing's metabolic system using biophysically based ecological accounting. We also compared the results with those of four other Chinese cities (Shanghai, Guangzhou, Ningbo, and Baotou) and China as a whole to assess Beijing's development status. From 1990 to 2004, Beijing's metabolic flux, metabolic intensity, and metabolic density increased significantly. The city's metabolic processes depend excessively on nonrenewable resources, but the pressure on resources from outside of the city decreased continuously. The metabolic efficiency increased by around 12% annually throughout the study period. Beijing had a highest metabolic fluxes and density compared with the four other cities; its metabolic efficiency was lower, and its metabolic intensity was higher. Evaluating these metabolic indicators revealed weaknesses in the urban metabolic system, thereby helping planners to identify measures capable of sustaining these urban metabolic processes.  相似文献   

20.
Water environmental planning and management has become essential for guiding the water pollution control activities. Past water pollution control activities have been site specific, with little thought on water quality standard reaching at the watershed scale. Based on the watershed approach, a seven-step methodological framework for water environmental planning and management was developed. The framework was applied to water environmental planning and management of the Lake Qilu watershed in Yunnan Province, China. Results show that the reduction amount of total nitrogen (TN) under the plan is 1,205 tons per year so that the target of environmental capacity can be reached in 2020. Compared with traditional methods, the framework has its prevalence and could be generalized to analogous watersheds.  相似文献   

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