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21.
沙滩质量评价是有效的沙滩管理工具。“蓝旗”标准是目前世界上认可度最高的沙滩评价标准。文章基于“蓝旗”标准,根据国内外已有沙滩质量评价体系,结合实地调研和问卷调查,构建适用于万平口沙滩的质量评价体系。评价结果表明:(1)万平口环境因素、安全与教育和环境管理准则层评价结果均为良好,社会因素准则层达到优质等级,说明万平口风景区作为旅游地,其气候条件适宜,服务水平和安全及教育水平都较为发达。(2)万平口沙滩的自然条件本底优良,是最能体现日照“蓝天、碧海、金沙滩”的特色景区。但由于自然及人为因素造成的沙滩侵蚀退化现象严重,影响了沙滩的可持续发展。根据评价结果及万平口与“蓝旗沙滩”的对比差异,认为万平口建设“蓝旗沙滩”,需要完善景区水质监测、加强景区内及周边环境管理、重视沙滩养护、完善基础设施的投放、进一步提高景区的服务水平、重视景区内安全保障及加强景区的宣传,提高公众对“蓝旗”的认知度。 相似文献
22.
根据日照市海岸带2个重点海滩所采集的样品,通过粒度、磁化率、主微量及稀土元素等方面的调查资料,综合分析了研究区沉积物类型、分布特征、搬运路径及物质来源。结果表明,研究区沉积物类型以砂为主,在平行海岸方向上,沉积物粒径自北至南由细变粗。在垂直海岸方向上,从滩肩到滩面再到低潮线处,沉积物粒径逐渐变细。海滨国家森林公园海滩的分选性要好于万平口海水浴场海滩。沉积物受黄海沿岸流影响,多自北向南运移。海滩中浅部物质的来源与陆内一侧基岩中斜长片麻岩和二长花岗岩的关系较为密切,深部物质的来源与靠海一侧基岩中花岗斑岩和花岗闪长岩的关系较为密切。 相似文献
23.
This article analyzes the impact of changing housing and neighborhood characteristics on the accessibility of neighborhood businesses using Long Beach, California, as a case study. Although advocates of smart growth and New Urbanism encourage land use mixing, aggregate-level analysis can be too coarse to pick up on fine-grained aspects of urban streetscapes. This study uses assessor parcel records and a point-based business establishment data set to analyze city-wide patterns of accessibility from individual dwelling units to thirty-one types of neighborhood businesses, including grocery stores, service shops, drug stores, doctor's offices, and banks. Regression results compare parcel-level and neighborhood-level drivers of accessibility between 2006 and 2015 to gauge the aggregated effect of recent economic, demographic, and built environment changes on this aspect of urban spatial structure. Larger homes in older, multiunit buildings and higher income neighborhoods show substantial increases in accessibility to most establishment types, suggesting a trend toward both greater accessibility and larger dwelling units—despite the traditional trade-off between access and space. Although gradual increases in home and business density increased overall accessibility over this period, weaker neighborhood-level results indicate that this trend is less pronounced in high-poverty and non-white areas. 相似文献
24.
未来海平面上升对厦门海滩侵蚀的测算 总被引:2,自引:2,他引:0
本文通过波浪计算和理论海滩剖面方程的拟合,以Bruun模式为基础,根据Everts剖面积分方法,测算了厦门厦门大学海滨浴场、鼓浪屿港 仔后海滨浴场沙滩未来100a海平面上升引起的海滩后退量值。与此同时,计算了Bruun模式的结果。计算结果表明,两处海滨浴 滩的后退值分别为14.81和13.95m与Bruun模式的结果相当接近。 相似文献
25.
The cross-shore profile and the textural distribution of foreshore sediments of Ganpatipule beach along Maharashtra coast covering two annual cycles are examined. Ganpatipule beach depicts erosion and accretion of the berm, reduction and widening of foreshore widths during the monsoon (June–September) and post-monsoon (October–May), respectively with net sediment accretion during the study period due to the changes in the wave characteristics. A direct correlation is observed between the median sediment grain size and beach-face slopes signifying high wave energy ensuing to a gentle to very gentle slope. The sediments are mainly medium grain size, moderately well sorted, bimodal, very fine skewed to very coarse skewed and very platykurtic to very leptokurtic in nature. The binary plots of the textural parameters (mean, skewness, kurtosis, and standard deviation) depicted a characteristic beach environment of deposition. The study shows that the sediment is concentrated in the environment of rolling and bottom suspension. The study on grain size distribution of sediments could be used to assess the wave energy condition prevailing along the coastal area. 相似文献
26.
John D. Booth 《新西兰海洋与淡水研究杂志》2013,47(3):231-265
Twelve common bivalve larvae occurring in the plankton from the Bay of Islands (35°15'S, 174°10'E), Wellington Harbour (41°16'S, 174°51'E), and off Raumati Beach (40°56'S, 174°58'E), New Zealand, during 1970–72 are described and, wherever possible, provisionally identified. The seasonal occurrences of these larvae in the plankton are also described. Information on the spawning cycles of some New Zealand adult bivalves is reviewed; although some species have a short (4 months or less) spawning season, for most it is much longer, possibly with ‘trickle’ spawning through several months of the year. 相似文献
27.
N. Angusamy 《Marine Georesources & Geotechnology》2013,31(2):77-102
Exploration for placer deposits, especially for ilmenites, has been undertaken systematically in the southern coast of Tamil Nadu, India. On the basis of drainage network. Coastal landforms, lithology, and neotectonics, the study area has been grouped into five sectors: Mandapam, Valinokkam, Tuticorin, Manappad, and Kanyakumari. Ilmenites are abundant in Kanyakumari (Max. 53.39 wt%) and Tuticorin (Max. 20.88 wt%) sectors, negligible in Manappad (Max. 0.60 wt%) and Valinokkam (Max. 3.88 wt%) sectors and absent in the Mandapam sector. The abnormal enrichment of ilmenites in the Kanyakumari sector in the absence of any drainage network points to the possibility of a relict source. Literary and scientific evidence corroborates the existence of an Eastern Gondwana land called Lemuria, South of Kanyakumari which was later submerged in the Flandrian transgression. The association of other heavy minerals with ilmenites like overgrown and outgrown zircon supplements the idea of a longer stay of ilmenites in the depositional basin. Ilmenites from these fossil strandlines must have been reworked by the present day coastal processes and deposited in favorable bay-like NE-SW coastal configurations in Kanyakumari-Kuttankuli and Kallar-Vaippar regions under high energy wave conditions. The present study has disclosed the enrichment of ilmenites up to 1 m in depth in the above two zones which can be commercially exploited. The present study also calls for confirming part of the lost continent called Lemuria or Eastern Gondwana by systematic scientific investigations. 相似文献
28.
A 2-year set of profile data from Ovari to Kanyakumari Beach,SE India has been analysed by using empirical orthogonal function(EOF) techniques to identify characteristic patterns of temporal and spatial variation in the sediment volume of the beaches.The results show that variation in the sediment volume of the beach is determined by interaction between the biennial and seasonal exchanges.EOF analysis the pattern of alongshore sediment exchange along the study area.The method facilitated separation of onshore-offshore and alongshore modes of sediment transfer and identification of the patterns of alongshore sediment exchange.The eigenfunction modes confirm the dominance of biennial,annual,and biannual sediment transfers occurring on study area.The sediment movement along the shoreline of study area is mainly governed by the forces associated with the incoming waves and the availability of sediments within the area.The present investigation has been made as an attempt to appreciate the sediment movement in relation to wave activity along the coast.The longshore sediment transport is intensive in the northerly direction as compared to southerly direction.The normal condition is for and to be moved annually or more frequently in the shallows and on the beach.Waves and wave-driven currents cause longshore drift of sand along the beach and offshore. 相似文献
29.
This study has demonstrated a reliable method of quantifying the total mass of litter on a beach. It was conducted on Ookushi beach, Goto-Islands, Japan, and uses a combination of balloon-assisted aerial photography and in situ mass measurements. The total mass of litter over the beach was calculated to be 716 ± 259 kg. This figure was derived by multiplying the litter-covered area (calculated using balloon-assisted aerial photography) by the mass of litter per unit area. Light plastics such as polyethylene made up 55% of all plastic litter on the beach, although more work is needed to determine whether lighter plastics are transported to beaches more readily by winds and ocean currents compared with heavier plastics, or whether lighter plastics comprise a greater percentage of marine litter. Finally, the above estimates were used to calculate the total mass of metals released into coastal ecosystems via plastic litter on beaches. 相似文献
30.
Sabino R Veríssimo C Cunha MA Wergikoski B Ferreira FC Rodrigues R Parada H Falcão L Rosado L Pinheiro C Paixão E Brandão J 《Marine pollution bulletin》2011,62(7):1506-1511
Whilst the potential impact on beach users from microorganisms in water has received considerable attention, there has been relatively little investigation into microbial contaminants in sand. Thirty three beaches across Portugal were analyzed during a five year period (2006-2010) to determine the presence of yeasts, pathogenic fungi, dermatophytes, total coliforms, Escherichia coli and intestinal enterococci in sand.Our results showed that 60.4% of the samples were positive for fungi and that 25.2% were positive for the bacterial parameters. The most frequent fungal species found were Candida sp. and Aspergillus sp., whereas intestinal enterococci were the most frequently isolated bacteria. Positive associations were detected among analyzed parameters and country-regions but none among those parameters and sampling period.Regarding threshold values, we propose 15 cfu/g for yeasts, 17 cfu/g for potential pathogenic fungi, 8 cfu/g for dermatophytes. Eighty four cfu/g for coliforms, 250 cfu/g for E. coli, and 100 cfu/g for intestinal enterococci. 相似文献