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1.
Cycles of storm destruction and rebuilding of human facilities are as much a part of a predictable cycle of shoreline change as destruction and re-establishment of landforms and wildlife habitat by natural processes. An evaluation of the human-induced and natural geomorphic responses to three storms in two vulnerable developed areas in New Jersey reveals that storms can have limited effect in re-establishing a natural coastal resource base of lasting significance. Reconstruction of coastal landscapes by human action may be more rapid than natural restoration, decreasing the likelihood for geomorphic features to develop based on natural processes. Reliance on storm processes to create new natural habitat in locations where there is human investment in buildings and support infrastructure is not realistic unless a proactive stance is taken to include naturally-functioning characteristics of the coastal system in reconstruction efforts. By striving to control construction of shorefront buildings to reduce their potential for damage, managers may be taking attention away from the separate but critical issue of ensuring that post-storm reconstruction effort include the potential for replacing loss of natural geomorphic features and wildlife habitat.  相似文献   
2.
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   
3.
崇明东滩候鸟自然保护区的动态变化   总被引:4,自引:0,他引:4  
在80年代末期的鸟类及其生境调查研究基础上,正式提出拟建的上海市崇明东滩候鸟自然保护区,5年来随着滩涂的游涨及90年代初期人工围垦的影响,滩涂自然植被和鸟类的种类,数量,分布也随之有了相应的相应的动态变化。该文在新的调查资料基础上,对崇明东滩鸟类赖以生存地自然植被恢复,候鸟食料的容量分析等作了研究;同时,还论述了崇明候鸟自然保护区的界线范围及其动态变化,以及保护区内部3个功能小区的动态等。  相似文献   
4.
Litter at beaches can come from more than one source and determining the proportions to assign pollution to different sources is very complex. There is no widely accepted methodology at present that links litter items to their source. The aim of this study was to create a method of assigning a source to litter found on beaches of the Bristol Channel but which could equally be used on any beach. Various methods that attempt to establish the source of beach litter were evaluated; their strengths, weaknesses, applicability and reliability for use on Bristol Channel, UK beaches were considered. Elements of existing methods coupled with new ideas were utilized in the production of a ‘refined’ methodology: consequently a new method of assigning a source to beach litter was developed. The developed ‘Matrix Scoring Technique’ was applied to data collected at Minehead beach on the Bristol Channel, UK. Several numerical and nomenclature variations were used to produce a system that reflected the various sources and eliminated as much bias as possible. This cross-tabulated matrix scoring system can produce an insight into the contribution of different source groups to litter found on beaches. This novel approach requires further testing with emphasis on a control data set.  相似文献   
5.
Since February 1999, the Municipal Wastewater Treatment Plant (MWTP) of Balneário Camboriú, Brazil, started a complementary treatment with ClO2 application on its effluent. It was realized to minimize its impacts caused by increase of the population during summer. This study was realized in order to verify the influence of this compound in the water quality and the environmental evaluations. Samples of surface water were collected in this environment between January 1997 and June 2001 for chemical and microbiological surveys. The results had shown that after application of ClO2, fecal coliforms were decreased about six times in the beach (2.3 × 103 to 3.5 × 102 MPN/100 ml) and three times in the river (3.3 × 104 to 1.0 × 104 MPN/100 ml), during summer time. NH4 + showed an increase of about four times and 1.5 times, respectively, to beach and river. These results are showing the influence of ClO2 on chemical and microbiological parameters.  相似文献   
6.
The quantity and quality of organic matter, and bacterial density and frequency of dividing cells were investigated in six microtidal mixed beaches of the Ligurian Sea (NW Mediterranean) to evaluate their main trophodynamic features. Concentrations of biopolymeric carbon (average 88.5?±?89.0 µgC/g) and the protein:carbohydrate ratio (on average lower than 1) were very low and classified these beaches as highly oligotrophic. The study of biochemical composition highlighted the nature of organic matter as being mainly refractory; furthermore, the quantitative differences observed along the across-beach gradient together with the unchanged pattern in qualitative features suggest that the organic matter in Ligurian beaches is prevalently of marine origin. This implies a negligible contribution of allochtonous and anthropogenic terrestrial input or in situ autochthonous production. Bacterial density displayed values ranging from 0.1–9.0 cell?×?108/g DW in the top 2?cm layer and showed a significant correlation with the quantity of organic matter. In addition, the frequency of dividing cells showed a positive correlation with the protein:carbohydrate ratio, suggesting that the biochemical composition of organic matter also has an influence on the active bacterial fraction. Because of the exposed nature, a strong coupling was found between the beach and the marine systems, and this seems to be of fundamental importance in terms of material and energy supply for the beach ecosystem. A shortage within this linkage was observed in summer owing to the strong environmental constrains leading to a sort of “beach desertification” and to a marked oligotrophy. Summer also has an effect of smoothing for spatial variability occurring within the biochemical and microbiological variables among the different beaches. The linkage observed between the sea and the land is the main factor controlling the origin and nature of sediment organic matter in these beaches also regulating bacterial abundances and the frequency of dividing cells.  相似文献   
7.
Sand-trapping fences modify the character of the coastal landscape and change its spatial structure, image, and meaning. This paper examines the relationship between these changes and fence usage at the municipal level, where most decisions about fence deployment are made. Use of fences in 29 municipalities on the developed coast of New Jersey is examined over a 6-year period. Interviews with municipal officers indicate that wooden slat sand-trapping fences are used primarily to build dunes to provide protection against wave uprush and flooding, but they are also used to control pedestrian traffic and demarcate territory. These uses result in changes in landforms and habitats. An aerial video inventory of fences taken in 2002 indicates that 82% of the shoreline had fences and 72% had dunes. Single and double straight fence rows are the most commonly used. Fences are often built to accomplish a specific primary purpose, but they can cause many different and often unanticipated changes to the landscape. The effects of a sand fence change through time as the initial structure traps sand, creates a dune that is colonized by vegetation, and becomes integrated into the environment by increasing topographic variability and aesthetic and habitat value. Sand fences can be made more compatible with natural processes by not placing them in locations where sources of wind blown sand are restricted or in unnatural shore perpendicular orientations. Symbolic fences are less expensive, are easy to replace when damaged, are less visually intrusive, and can be used for controlling pedestrian access.  相似文献   
8.
Integrated Coastal Zone Management as a strategy for achieving conservation and sustainable multiple use of the coastal zone includes various types of management initiatives. Due to natural phenomena such as tides and winds and to social and economic activities, coastal areas undergo transformation. Coastal erosion and the disappearance of beaches as a result of wrong planning decisions and lack of effective legislation are among the most damaging effects and to reverse them requires application of a series of engineering techniques. Beach nourishment projects as a way towards shore protection and utilization through recreational purposes in the Spanish and Italian coasts are noteworthy in this respect. In beach nourishment projects, the roles of various entities, both public and private, should be clearly indicated and in the evaluation and execution stage a series of questions should be answered for the successful completion of any nourishment project. Past projects in the Mediterranean and experiences from recent Italian projects in Anzio and Nettuno confirm this. For example, dredging of the entrance channel of the port of Anzio enabled middle-sized ferryboats once again to enter the port (which had not been possible before). This will in turn increase the tourism potential of the town. Nourishment of two beaches at these sites prevented further erosion and provided more area for recreational purposes. Expected economic contribution of beach nourishments to the regional authority was estimated for Nettuno and Anzio; the resulting theoretical payback period was found to be 3 yr for the former and 15 yr for the latter.  相似文献   
9.
This paper concludes the publication of theJournal of Coastal Conservation from 1995–2004 after the European Coastal Union and the Publishers decided to terminate the production of the journal. We look back at the 206 research papers published in this period while concentrating on Geographical and ecological variation, Focuses and trends, and Progress in European coastal conservation and management. Three indices are added: (1) a list of the 206 papers; (2) an Author Index; and (3) a Subject Index based on the titles, keywords and some additional important subjects found in the tables and figures.  相似文献   
10.
Beach conservation and management on the high-value French Riviera in southeastern France have had mixed fortunes in shoreline economic development strategies over the past half century. Prior to 1965, socio-economic growth related to immigration and tourism resulted in considerable pressure on the coastal zone, leading in particular to beach erosion and degradation of beach environmental quality. Between 1965 and 1980, over 20% of the 132 km-long French Riviera was permanently altered through the implantation of yachting harbours and reclamation fill structures, while beach-based recreation had a rather low ranking as a development choice, except in the two major resorts of Cannes and Nice which exhibit a densely urbanized seafront. On this preponderantly boldrocky coast, the mediocre recreational value inherited by many of the beaches from the regional geologic setting, and from development pressures and earlier errors in coastal management, left them vulnerable to appropriation and so-called ‘valorization’ by yachting harbour and estate developers. Over the last decade, artificial shoreline development has virtually ceased, in response to several more or less interrelated factors. These include relative stagnation of socio-economic growth, increasing development and maintenance costs of yachting harbours, saturation of the yachting harbour market as a result of the burgeoning of new, often cheaper, resorts and of reconversion of commercial and shipbuilding ports to leisure ports in the Mediterranean, more stringent legislation, since 1986, on the implantation of residential and major engineering structures on the coastline, pressure for conservation of the cultural and environmental heritage, and greater demand for beach recreational space. This situation has forced a diversification of shore-based activities, as it has been realised that better managed beaches may balance economic aspirations while contributing to enhanced environmental quality and sensible shoreline conservation. This change in strategy has entailed considerable efforts and money on the improvement of coastal water quality, the provision of amenities for beach-goers, and especially the nourishment of eroding beaches and the creation of several artificial beaches. The extent to which beaches will continue to play a role in the sustainable development of French Riviera resorts will depend largely on the capacity of local authorities to maintain environmental quality in the face of inherited and persistent handicaps such as beach erosion.  相似文献   
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