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881.
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   
882.
溶解态有机氮(DON)是土壤中活跃的氮库,其生态环境行为与它的化学组成和粒径分布密切相关。为评估热带滨海区不同土地利用方式对不同粒径中土壤溶解性有机氮组成特征的影响,从水稻田、橡胶园、菜园和果园采集土壤样品,通过一系列微滤和超滤(0.7,0.45,0.2,0.1μm,100,10,1 kDa)对土壤溶解性有机氮分级,并使用连续流动分析仪、三维荧光光谱和红外光谱研究了滤液中溶解态有机氮、无机氮的含量及荧光组分和有机官能团特征。结果表明,4种土地利用背景下土壤DON值的范围为5.25-10.88 mg·kg^-1,其大小顺序为水稻>菜园>果树>橡胶,且DON与溶解性总氮(DTN)的比值范围为26.08%-67.11%,其中橡胶土最高,水稻土最低;不同粒径下4种土地利用类型土壤DON主要集中在<100 kDa的粒径中,其值范围为4.85-9.48 mg·kg^-1,占全量的85.89%-92.41%。三维荧光光谱(3D-EEMs)及平行因子分析表明,4种土地利用背景下土壤DON含有两种类腐殖质组分及一种类蛋白质组分,且以类腐殖质组分为主,占比54.00%-77.67%;类蛋白组分对土地利用变化敏感,且随着粒径的减小,类蛋白组分占比增加,在<1 kDa组分中比例最高。红外光谱结果表明,4种土地利用背景下土壤DON主要在6个位置有相似的吸收峰,包含3410 cm^-1、1636 cm^-1、1402 cm^-1、1138-1035 cm^-1、673 cm^-1、602 cm^-1,不同土地利用背景下各吸收峰的透光度不同,强度最大的吸收来自游离的胺类N-H伸缩振动;水稻、菜园土壤DON芳香物质含量较高,结构较复杂。了解DON的组成与粒径分布对土地利用的响应,对进一步研究其生态环境行为具有重要意义。  相似文献   
883.
本文介绍了1990—1991年对上海粮田锌和铅的生物地球化学研究.阐述了锌和铅在上述地区的富集和迁移规律.研究了结累锌和铅的地球化学栅栏以及谷物对锌和铅的吸收与富集.  相似文献   
884.
本文以江英乡为例,阐明了广东石灰岩山区土壤资源的生态环境特点。针对这些特点,我们提出了顺应生态环境、充分发挥小气候优势、推广良种良法、调整农业结构、发展外向型绿色企业以及保水保土等一系列综合开发利用的措施,并在江英乡付诸实施。实践证明,这些措施具有明显的经济效益和社会效益,从而为广东石灰岩山区开发利用土壤资源、发展农业经济提供了参考依据。  相似文献   
885.
简述了柴河水库水源涵养对保护水源水质、改善水质的作用;针对柴河水库水源涵养区氮磷污染、面源污染和生态破坏等存在的主要环境问题,提出了可操作性较强的保护措施。  相似文献   
886.
发展农村沼气建设生态家园   总被引:1,自引:0,他引:1  
周超贤  林瑞如 《生态环境》2004,13(3):459-460
以沼气建设为核心的“猪沼果”等生态家园技术模式的推广,在实施农业可持续发展战略中发挥了越来越重要的作用。这种模式,在促进农业结构调整、增加农民收入的同时,能保护和改善生态环境、高效利用资源、提高农产品的质量安全和改善农村环境卫生,从而实现家居温暖清洁化、庭院经济高效化和农业生产无害化的生态家园富民目标。  相似文献   
887.
The United States Environmental Protection Agency (USEPA) recommends the use of Escherichia coli (E. coli) and enterococci as indicators of enteric pathogens in fresh waters; however, fecal coliform analyses will remain important by virtue of the large amount of historic data collected in prior years. In this study, we attempted, in a real-world situation (i.e., a rural inland watershed in the Piedmont of South Carolina) to compare different bacterial indicators and methods to one another. We compared fecal coliforms, enumerated by membrane filtration with E. coli, enumerated by a commercialized enzyme substrate method and observed E. coli/fecal coliform ratios of 1.63 and 1.2 for two separate tests. In the same watershed, we observed an E. coli/fecal coliform ratio of 0.84 when we used the commercialized enzyme substrate method for both enumerations. Given these results, users of such data should exercise care when they make comparisons between historic membrane filtration data and data acquired through the use of the more modern enzymatic methods. Some sampling and side-by-side testing between methods in a specific watershed may be prudent before any conversion factors between old and new datasets are applied.  相似文献   
888.
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   
889.
Assessment of community noise problem in Greater Beirut Area,Lebanon   总被引:1,自引:0,他引:1  
Over the last two decades, urban noise has been increasingrapidly, primarily in urban areas, due to population growthand the increase of certain noise sources. The main objectiveof this paper is to assess the sources and possible impactsof the community noise problems in Lebanese urban areas,particularly the Greater Beirut Area. The causes and effectsof community noise pollution are briefly presented. Soundpressure levels that were measured to define existing noiseexposure levels in various locations in the Greater BeirutArea are also presented. The attitudes toward noise pollutionand perceived annoyance impact on a sample of 1,038 exposedresidents are described. The association between measurednoise levels and sources, as well as annoyance, is examinedusing correlation analysis and linear and multiple linearregressions. A set of recommendations is presented to reducecommunity noise problem in Greater Beirut Area.  相似文献   
890.
综合遥感解译、宗地调查和入户问卷调查方法,研究黄淮海平原农区禹城市5个村庄的宅基地时空演变特征和不同退出标准的宅基地整治潜力和整治效果。研究结果表明:(1)改革开放以来,农村宅基地经历了剧烈扩张,调研村庄的宅基地平均扩张了3.7倍。2015年户均宅基地高达1.6宗,30.8%的农户存在“一户多宅”现象,28.5%的房屋被闲置或废弃。(2)2000年以前,调研村庄的宅基地空间扩张模式以飞地式为主,2000年后被填充式和蔓延式所取代。分村庄来看,宅基地空间扩张受到主要交通干线布局、土地资源禀赋和村庄初始布局等因素的影响。(3)调研村庄宅基地整治具有较大的理论潜力,可节约56%的村庄居住用地。基于两套退出标准方案的宅基地整治可分别节约26%和36%的村庄居住用地,但均与理论潜力存在较大差距。(4)未来宅基地试点改革亟需在推进转移人口市民化、建立宅基地退出补偿价值体系、探索退出的宅基地转化为集体经营性建设用地的办法等宏观体制机制推进,并在微观层面依据农户就业结构和土地资源禀赋分类施策。  相似文献   
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