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81.
1IntroductionChinahasalongcoastalline.Since1980’,economyincoastalareashasbeendevelopingfast,alongwiththeincreasingpopulation....  相似文献   
82.
西部大开发中生态环境的保护与建设   总被引:3,自引:0,他引:3  
加强生态建设是国家实施西部大开发战略的工作重点之一,根据西部地区的地域特征,气候特征及其脆弱的生态环境,西部大开发生态环境建设必须走一条可持续发展道路,可持续发展是以控制人口,节约资源,保护环境为重要条件的,其目的是使经济发展同人口增长,资源利用和环境保护相适应,实现资源,环境的承载能力与经济社会发展相协调,本文通过对西部自然条件和生态环境的分析,提出了生态环境保护和建设的相关措施。  相似文献   
83.
台湾含金斑岩铜矿床   总被引:1,自引:0,他引:1  
台湾省主要金属矿产为金和铜 ,本文只介绍斑岩铜矿。为了解台湾斑岩铜矿产出的地质背景 ,本文简要分析了台湾地区的地质概况 ,以及台湾斑岩铜矿与环太平洋带其他同类型铜矿床的对比情况。台湾斑岩铜矿主要产在台湾省东部海岸山脉及临近的小岛上。最大的铜矿床为奇美铜矿 ,已达特大型规模。斑岩铜矿的出现与欧亚、太平洋两大板块碰撞有密切关系。本文较详细地介绍了奇美铜矿床产出的时代、岩石、围岩蚀变及矿体分布特征 ,同时还简要介绍了台湾东海岸的都峦山及兰屿岛斑岩铜矿矿化情况。  相似文献   
84.
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   
85.
江苏海岸带土壤重金属来源解析及空间分布   总被引:6,自引:0,他引:6  
吕建树  何华春 《环境科学》2018,39(6):2853-2864
以江苏省响水如东段海岸带为研究区,系统采集了239个表层土壤样品,分析测试了Cd、Cr、Cu、Hg、Ni、Pb和Zn等7种重金属元素,综合运用多元统计和地统计方法,探讨了研究区土壤重金属的主要来源,绘制了重金属的空间分布图.结果表明:(1)江苏响水如东段海岸带土壤Cd、Cr、Cu、Hg、Ni、Pb和Zn的平均含量分别为0.14、64.23、24.15、0.026、29.16、22.24和77.94 mg·kg~(-1),Cd、Cu、Hg、Pb和Zn存在较为明显的富集,Cr和Ni的平均值低于江苏滨海土壤背景值.(2)Cd、Cr、Cu、Ni、Pb和Zn在海积物母质发育土壤中的含量显著低于河流冲积物、潟湖相沉积物和三角洲沉积物母质;Cd、Cu、Hg、Pb和Zn在城镇建设用地的平均含量显著高于其他地类.(3)Cr和Ni为自然来源元素,受到成土母质的控制;Cd、Cu、Pb和Zn受到成土母质和人类活动的共同影响,人为源主要包括工业、交通排放和农业活动;Hg为人为来源,受到人为排放的大气沉降的影响.(4)Cd、Cu、Pb和Zn的高值区分布在研究区的北部、南部和西部,Hg的高值区分布在研究区的西部和南部的城镇密集区.  相似文献   
86.
王庆 《灾害学》1998,13(3):51-55
根据距今4000a以来海面波动与河谷地貌、海岸地貌发育之间的关系,未来海面上升有可能导致入海河流发生溯源堆积,使河床纵剖面发生调整,海面上升在导致某些岸段蚀退的同时,还有可能使某些岸段的海淤进;河流溯源堆积导致的入海泥沙减少,可能使原有海岸蚀退加剧.对海面上升可能给山地海岸资源与环境带来的影响,建议加强观测与研究,进行合理规划与管理,并采取必要的工程措施.  相似文献   
87.
吉林西部农业生态环境问题及对策   总被引:8,自引:0,他引:8  
章光新  杨建锋  刘强 《生态环境》2004,13(2):290-292
在自然因素和人为因素的影响下,吉林西部农业生态环境问题日益突出,土地退化严重,直接表现为“三化”(即土地盐碱化、草原退化和土地沙化)。盐碱地面积已增至160.69104 hm2,与50年代相比,盐碱地面积增加52.79104 hm2,平均每年增加1.35104 hm2,年递增率1.3%;建国初期,嫩平原吉林省西部草地面积252.9104 hm2,到了1999年,草地面积仅为122.3104 hm2,年递减率约2.6%,而且草原的质量也在下降。目前,沙地面积68.6104 hm2,土地沙化局面已基本控制。文章系统分析农业生态环境恶化的原因和驱动机制,提出综合防治对策和措施。  相似文献   
88.
‘Coastal squeeze’— an historical perspective   总被引:1,自引:0,他引:1  
The use of salt marsh for agricultural use has probably been going on for thousands of years. This paper will look at the situation in southeast England, particularly the Wash. Here enclosure for extended grazing and over the last several hundred years, for arable cultivation, may have taken place since Roman Times. An enclosure of Freiston Shore salt marsh (1979) and a proposed further enclosure at Gedney Drove End at about the same time raised concerns about the cumulative effect of these developments on nature conservation interests. These concerns prompted the nature conservation agencies to oppose the Gedney Drove End enclosure. Though the conservation argument did not persuade the Government that no further enclosure should take place, economic circumstances changed such that the pressure for the creation of new agricultural land diminished. This marked the end of ‘reclamation’ in the Wash. Since then, in the UK at least, there have been no further enclosures of salt marsh for agriculture. What were the arguments that lead to this change? Up to this point the perceived wisdom, in the Wash at least, was that as enclosure took place new inter-tidal land was created to seaward— with no net loss of inter-tidal land. Today we accept that this is not the case and a policy of managed re-alignment has increasingly been adopted in England, at sites ranging from the Porlock shingle ridge in north Devon to the salt marshes of Freiston in the Wash. It is argued that recognition of ‘coastal squeeze’ probably began in the Wash some 20 years ago. It would appear that we are now witnessing a reversal of this trend. How far will it take us? Will we see a return of the large expanses of tidal swamp around the Wash and elsewhere along the southern North Sea coast? Is this an inevitable consequence of global warming? This paper provides an historical perspective of the issues and arguments that have led us to recognize ‘coastal squeeze’ and the importance of dynamic coast, including the European Commission’s ‘EURosion Project’, which reported in 2004 (Salman et al. 2004).  相似文献   
89.
西部生态环境现状的经济学分析   总被引:4,自引:0,他引:4  
陈伟 《重庆环境科学》2001,23(2):21-23,29
西部生态环境的恶化是一个人与自然叠加影响的历史过程,但人为对生态环境的影响却越来越大。本文试图从产权、、收入和寻租理论等方面来分析问题的根源,并提出了建立对策。  相似文献   
90.
Freshly deposited surface sediments from the Alexandria coastal zone were collected and analysed in 1995 for their trace metal concentrations. Metal concentrations in the sediments vary between sites within a wide range for copper, zinc, iron, lead, chromium and cadmium. the statistical analysis between the metal concentrations and the different constituents (organic carbon, total nitrogen, silt, clay and total iron) showed significant correlations. the enrichment factors for the sediments ranged between 3 and 4-fold for copper, chromium and zinc and reached up to 9-fold for lead and 113-fold for cadmium. the highest index for cadmium and lead may be attributed to the anthropogenic inputs from the surrounding area, where they are highest in lower discharge areas.  相似文献   
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