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331.
ABSTRACT: The purpose of this paper is to describe a land use and environmental planning model. Map overlays were used for analyzing and aggregating economic, social, and environmental data. Various land use categories were evaluated using a numerical scoring system. These scores were then used to assist in the development of land use regulations in a coastal county in South Carolina.  相似文献   
332.
To determine the level of total hydrocarbon concentrations (THCs) along the eastern coastal regions of Peninsular Malaysia, samples of subsurface seawater (1 m) and surface sediments were collected from several sampling stations between June and August 1993. THCs in seawater and sediments as determined by fluorescence spectroscopy ranged from 1.4 to 21.8 µg L-1 (Seligi crude oil equivalents) and from 0.79 to 20.0 mg kg-1 (dry weight Seligi crude oil equivalents) respectively. In comparison to results obtained in similar surveys in Malaysian waters, the levels of THCs found in the present study were significantly lower indicating lower hydrocarbon contamination in the area studied.  相似文献   
333.
High Spatial and Temporal Variability of Dry Deposition in a Coastal Region   总被引:1,自引:0,他引:1  
A real meteorological situation characterized by strong spatial and temporal variability of the meteorological fields in a coastal region of eastern Denmark is examined in view of the transport of a passive tracer and dry deposition. Model simulations using a full mesoscale NWP model (COAMPSTM) at different horizontal resolutions are performed. A realistic simulation showed that the differences in the amount of dry deposited matter can reach one order of magnitude and larger, during the period of one afternoon, depending on the model horizontal resolution. In addition, the results of an idealized experiment with straight coastline indicate that the horizontal model resolution alone is responsible for most of the differences. This study confirms the importance of high spatial and temporal resolution modelling for environmental applications.  相似文献   
334.
This paper examines a 3-yr EU LIFE-funded project for the management of two especially protected areas on the Maltese coast. Project partners are the Euro-Mediterranean Centre on Insular Coastal Dynamics (ICoD), the Gaia Foundation and the Ministry for the Environment of Malta. Project sites are the Ghajn Tuffieha area on the northwest coast of Malta, and the Ramla Bay area on the island of Gozo. While both sites are in a relatively pristine state and comprise a number of features of ecological and scientific importance, they are also prime recreational areas, hosting thousands of visitors especially during the summer months. The challenge is to manage these sites in a sustainable manner in order to protect their unique ecology while simultaneously controlling and managing the human activities taking place there. The following sequence of activities is being implemented at both sites: surveys of the resources present (biodiversity, habitats, geological and hydrological features, and archaeological heritage), implementation of first intervention measures, and the drawing up and implementation of site-specific management plans, including rehabilitation and protection of biodiversity and habitats, regulations for site use, and awareness raising and educational measures. The management structure of this project supports the concept of decentralization of management of protected areas, through the granting of responsibility for the direct management of these sites to a non-governmental organization, under joint government/EU funding. This paper thus presents the project as a model for similar initiatives for the management of protected sites in the Mediterranean.  相似文献   
335.
东南沿海中生代安山岩的地质意义   总被引:1,自引:0,他引:1  
在中国东部大陆边缘中生代火山岩带中 ,东南沿海火山岩岩性岩相出露最全 ,火山地质调查研究程度较高。以往的研究主要集中于大面积酸性火山岩和与之共生的玄武岩 ,而对安山岩注意不够。作为过渡性岩类 ,安山岩的成因研究对于探讨中生代火山岩带物质来源、岩浆分异演化、大地构造背景等具有不可替代的作用。近年来在东南沿海新生代玄武岩中陆续发现了一些基性麻粒岩包体 ,为研究底侵作用与壳幔作用过程提供了珍贵的实物材料。结合基性麻粒岩包体的研究 ,进行系统的安山岩成因研究 ,对于研究中生代火山岩带成因、进而探讨东部大陆边缘形成演化动力学过程 ,具有重要意义  相似文献   
336.
研究了江苏省沿海地区覆盖与种植对轻度盐渍化土的水分、盐分、温度、养分等生态环境以及覆盖对大麦生长发育和产量的影响。结果表明:春旱季节,覆盖可以减少土壤水分蒸发,抑制盐分表聚,降低土壤溶液浓度和土表温度,增加土壤有效养分,种大麦后由于植株的蒸腾作用,使土壤水分降低,但土壤盐分和溶液浓度仍低于裸地。盆栽试验结果还显示,覆盖种麦有效地促进了大麦生长发育,显著地提高了大麦产量。  相似文献   
337.
This work was conducted to analyse pressing and competingdemands of water in Northeast Sicily, Italy. In thisarea, looking at the Ionian Sea, freshwaters and coastalseawaters have been studied on the quality and on thetransport processes of pollutants. Attention has beenfocused on chemical and microbial parameters proposed byEuropean Directives for drinking freshwaters and bathingseawaters. The findings show that the ground freshwaters areof good quality but the surface ones, particularly torrentsand correlated under-river aquifers, are clearly polluted.The characteristics of the coastal seawaters are accordingwith those of the closely bound up estuarine waters.Contamination is due essentially to discharge of raw sewagein the watercourses by public and private pipes. The impactis usually less evident during the wet season because rainand seastorms dilute the polluting load, but in dry periodsthis pollution causes loss of habitat and deleterious effectson environment. A database has been developed to provide agraphic and mapping display interface of the area studied andto assist the management of the studied fluvial basins.  相似文献   
338.
Sea-level rise involves increases in the coastal processes of inundation and erosion which are affected by a complex interplay of physical environmental parameters at the coast. Many assessments of coastal vulnerability to sea-level rise have been detailed and localised in extent. There is a need for regional assessment techniques which identify areas vulnerable to sea-level rise. Four physical environmental parameters – elevation, exposure, aspect and slope, are modeled on a regional scale for the Northern Spencer Gulf (NSG) study area using commonly available low-resolution elevation data of 10 m contour interval and GIS-based spatial modeling techniques. For comparison, the same parameters are modeled on a fine-scale for the False Bay area within the NSG using high-resolution elevation data. Physical environmental parameters on the two scales are statistically compared to coastal vulnerability classes as identified by Harvey et al. [1] using the Spearman rank-correlation test and stepwise linear regression. Coastal vulnerability is strongly correlated with elevation and exposure at both scales and this relationship is only slightly stronger for the high resolution False Bay data. The results of this study suggest that regional scale distributed coastal process modeling may be suitable as a first cut in assessing coastal vulnerability to sea-level rise in tide-dominated, sedimentary coastal regions. Distributed coastal process modeling provides a suitable basis for the assessment of coastal vulnerability to sea-level rise of sufficient accuracy for on-ground management and priority-setting on a regional scale.  相似文献   
339.
A long-term study of temperature, pH, turbidity, suspended solid, salinity, dissolved oxygen, biochemical oxygen demand and ammonia nitrogen has been performed in a port and harbour region in India for four years from December 1996 to November 2000. Marine water quality results showed no regular trend. The mean monthly values of temperature, pH, turbidity, suspended solid, salinity, dissolved oxygen, biochemical oxygen demand and ammonia nitrogen were in the range of 22.64 ± 0.4 to 29.05 ± 1.37 °C; 7.65 ± 0.04 to 7.81 ± 0.13; 28.8 ± 14.7 to 64.2 ± 32.0 NTU; 283.5 ± 81.8 to 356.0 ± 159.7 mg/L; 29.78 ± 7.18 to 29.78 ± 1.04 ppt; 4.67 ± 0.50 to 6.01 ± 1.02 mg/L; 5.41 ± 1.92 to 7.56 ± 2.1 mg/L; and 0.25 ± 0.07 to 0.63 ± 0.49 mg/L, respectively. The results of correlation analysis showed that biochemical oxygen demand (BOD) was inversely correlated dissolved oxygen (DO) and poorly correlated with all other parameters. Turbidity and suspended solid were moderately correlated with each other while salinity was moderately correlated with other water quality parameters. In factor analysis, four factors were drawn out of the eight variables, which represented 74% of the variance of the original data. Factor I was related to suspended solid and turbidity. Factor II represented mainly temperature and DO showing inverse relation between these two. Factor III implied the degree of pollution at any monitoring station. Factor IV included pH and salinity. It could be concluded that the factor model represented almost all the variables.  相似文献   
340.
Despite the advances in climate change modeling, extreme events pose a challenge to develop approaches that are relevant for urban stormwater infrastructure designs and best management practices. The study first investigates the statistical methods applied to the land‐based daily precipitation series acquired from the Global Historical Climatology Network‐Daily (GHCN‐D). Additional analysis was carried out on the simulated Multivariate Adaptive Constructed Analogs (MACA)‐based downscaled daily extreme precipitation of 15 General Circulation Models and Weather Research and Forecasting‐based hourly extreme precipitation of North American Regional Reanalysis to discern the return period of 24‐hr and 48‐hr events. We infer that the GHCN‐D and MACA‐based precipitation reveals increasing trends in annual and seasonal extreme daily precipitation. Both BCC‐CSM1‐1‐m and GFDL‐ESM2M models revealed that the magnitude and frequency of extreme precipitation events are projected to increase between 2016 and 2099. We conclude that the future scenarios show an increase in magnitudes of extreme precipitation up to three times across southeastern Virginia resulting in increased discharge rates at selected gauge locations. The depth‐duration‐frequency curve predicted an increase of 2–3 times in 24‐ and 48‐h precipitation intensity, higher peaks, and indicated an increase of up to 50% in flood magnitude in future scenarios.  相似文献   
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