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281.
Baseline resource information in an easily accessible form is a vital starting point for developing coastal zone management. On behalf of a wide-ranging group of organizations involved in the management of the U.K. maritime zone, the Joint Nature Conservation Committee (JNCC) is compiling a series of 16 regional volumes. The volumes contain multi-disciplinary coastal zone resource information arranged in ten chapters under the general title ‘Coasts and Seas of the UK’. These volumes form part of a series of paper and electronic publications of coastal information being produced by JNCC’s Coastal Directories Project and are designed to meet the needs of planners and all others involved in decision-making and management of the coast.  相似文献   
282.
The potential impact of future sea level rise and climate change on 15 Welsh coastal dune systems has been investigated. Historical Trend Analysis was undertaken using Ordnance Survey maps to quantify past shoreline change and to permit extrapolation of past trends to predict possible future shoreline positions by 2080–2100. Predictions were also made using the Bruun Rule relationship between sea level rise and shoreline response and an integrated method of assessment, Expert Geomorphological Assessment (EGA), which provides a ‘best estimate’ of future coastline change, taking into account such factors as geological constraints, the nature of past, present and future environmental forcing factors, and known coastal process–response relationships. The majority of the 15 systems investigated experienced a net increase in dune area over the last 100–120 years. Only one (Whiteford Burrows) experienced significant net area loss (>5 ha). EGA predictions suggest that several systems are likely to experience significant net loss of dune habitat over the next century, whilst continued net gain is likely to occur for systems where sediment supply rates remain high. Little net change is predicted in some systems. Considering the 15 dune systems together, it is considered unlikely that net dune habitat loss will exceed net gain over the next 100 years provided that there are no major disruptions to sediment supply and natural coastal processes.  相似文献   
283.
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   
284.
It is expected that the Baltic region becomes a major centre of economic growth and prosperity in Europe already during this decade (Anon. 2000). Therefore, an Agenda 21 for the Baltic region (Baltic 21) was developed to ensure a sustainable development. Especially the coastal ecosystems are subject to increasing anthropogenic pressure e.g. eutrophication, traffic, harbours, tourism or offshore wind parks. Eutrophication remains the main ecological problem in the Baltic Sea and has serious negative social and economical consequences. Inner and outer coastal waters play an important role as buffers and filters for the Baltic proper. Consequently, the utilization and preservation of their self-purification capacity is of great importance. Combined results of our own coastal research and of the international workshop ‘Baltic coastal ecosystems: structure, function and coastal zone management’ (Rostock University, November 2001) are presented here. Conclusions for an improved integrated coastal zone management of Baltic coastal ecosystems will be presented.  相似文献   
285.
In the coastal karstic region of SW Sardinia, from Capo Pecora in the north to Nebida in the south, many interesting geological monuments, ecotopes and several places of social and cultural interest that deserve preservation and valorization can be found. This mostly rocky coastline is characterized by the presence of a Cambrian sequence prevalently composed of limestones and dolostones and only locally of phyllites. A correct use of the many environmental and cultural monuments is necessary both to preserve and to valorize them; therefore they have to be properly managed in order to preserve their original natural conditions. Here, we describe and classify these monuments with the aim to propose an integrated model of sustainable development of this exceptional coastal landscape. Our model is based on several thematic maps according to which we propose the establishment of a natural reserve with specific geological and geomorphologic sites and the creation of several touristic circuits that are the basis for a further valorization of this territory.  相似文献   
286.
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   
287.
Abstract

Kerala, being a prominent tourist destination in the southern part of India with a coastline of 560?km, is prone to microplastic pollution. The National Oceanic and Atmospheric Administration (NOAA) of the USA defines microplastics as plastics of size < 5?mm–1?nm. To solve the problem of microplastic pollution, it is essential to track its source. As plastics are pervasive, it is challenging to track its source with a level of certainty required for implementing control strategies. Formulating and adopting suitable environmental forensic techniques to track microplastic pollution become important in this context. This study quantified the microplastic pollution of the Nattika coast, Kerala, India, and devised an environmental forensic investigation strategy for identifying the pathways and sources of microplastics. The microplastics of size 5–1?mm only were considered. The number of microplastics found in the Nattika Beach in 2017 and 2018 was 70.15 items kg?1 of sand and 120.85 items kg?1 of sand, respectively. The microplastics were subjected to analysis in FTIR and SEM as part of characterization. The forensic investigation of the pollution indicated that majority of the microplastic is sourced from the site/nearby area. The investigation could draw useful conclusions regarding the pathways of pollution. The fibrous microplastic, a significant component in the sample, was found to be sourced from the fishing net mending activities carried out close to the shore.  相似文献   
288.
The present study evaluates ground-based downward surface shortwave radiation (Rs) over the coastal region of Alicante (Southeastern Spain). Hourly measurements collected over the eleven-year period 2010-2020 are used. Two weather stations located over the region capital, Alicante, have been selected as representative of urban and suburban typologies. Two additional weather stations far from the city have been selected representing rural typologies. Rs is significantly reduced over the urban station during the morning hours within the winter season compared to the observations recorded over the suburban and rural stations, with a global mean difference of -81 and -120 W/m2 at 10 LT, respectively. However, no significant differences are obtained during the midday sun, with a global mean difference of -20 W/m2 between the urban and rural stations. With the aim of explaining these differences, the current paper investigates the relationship between Rs and different air pollutants: NOx, SO2, and fine particulate matter (PM2.5 and PM10) as well as the wind field measured at the urban and suburban stations. The results found in this work point towards a close relationship between Rs and NOx concentrations annual cycles, which are also influenced by the prevailing wind circulations observed over the study area. A global mean NOx concentration of 107 µg/m3 is observed over the urban station at 10 LT during the winter season. In contrast, these high concentrations are significantly reduced over the suburban station, with global mean value of 40 µg/m3 at 10 LT, for this period of the year.  相似文献   
289.
从1981年至2001年,深圳海域共记录发生赤潮85起,引发这些赤潮的生物种类约有36种。在这20余a间,引发赤潮的生物种类的演变趋势是:(1)引发赤潮的生物种类的多样性不断增高;(2)在引发赤潮的生物种类中常见种类逐渐减少,罕见种类逐渐增多;(3)在引发赤潮的生物种类中硅藻种类正逐渐减少,甲藻类及针胞类种类明显逐渐增多。据初步分析认为,这种演变趋势与深圳海域近20a来因沿海地区社会经济发展引起的入海污染物构成变化趋势有关,并且与全球不断演变的总趋势是相一致的。  相似文献   
290.
ABSTRACT: A stratified, spatially balanced sample with unequal probability selection was used to design a multipurpose survey of headwater streams in the Mid‐Atlantic Coastal Plain. Objectives for the survey include unbiased estimates of regional stream conditions, and adequate coverage of unusual but significant environmental settings to support empirical modeling of the factors affecting those conditions. The design and field application of the survey are discussed in light of these multiple objectives. A probability (random) sample of 175 first‐order nontidal streams was selected for synoptic sampling of water chemistry and benthic and riparian ecology during late winter and spring 2000. Twenty‐five streams were selected within each of seven hydrogeologic subre‐gions (strata) that were delineated on the basis of physiography and surficial geology. In each subregion, unequal inclusion probabilities were used to provide an approximately even distribution of streams along a gradient of forested to developed (agricultural or urban) land in the contributing watershed. Alternate streams were also selected. Alternates were included in groups of five in each subregion when field reconnaissance demonstrated that primary streams were inaccessible or otherwise unusable. Despite the rejection and replacement of a considerable number of primary streams during reconnaissance (up to 40 percent in one subregion), the desired land use distribution was maintained within each hydrogeologic subregion without sacrificing the probabilistic design.  相似文献   
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