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991.
Cornelia E. Nauen 《Environment, Development and Sustainability》2008,10(5):605-622
The paper examines preliminary experiences with international scientific cooperation in fisheries, aquaculture and coastal
zone issues through 90 projects in successive European Research Framework Programmes (FP4–FP6: 1994–2006). FPs had increasingly
ambitious objectives in response to international commitments, such as the Convention on Biological Diversity, the Millennium
Development Goals, the Johannesburg Plan of Implementation and dialogue with partner regions. Sustainable aquatic food production
in the context of respect for ecosystems was a central concern. Engagement with different social actors and attention to investment
in education, people and institutions enabled uptake of research results in education, innovation and some impact. The emphasis
in several recent projects on more integrated analyses and knowledge products in the public domain is an encouraging response
to the growing crisis of aquatic resource systems. It is suggested that significant up-scaling will be required. This might
be done through institutional internalisation and better translation of research results into policy developments supportive
of transitions towards sustainable production systems and ecosystem rehabilitation. Capacity building to use research in novel
ways and other enabling mechanisms need to be put in place to increase societal and environmental benefits of the research.
相似文献
Cornelia E. NauenEmail: |
992.
根据林业部与世界银行达成的协议,在我国60个县市设立世行贷款“国家造林项目”环境监测点,并对监测信息进行科学管理。本研究建立了基本情况库、水土流失监测库、监测结果汇总库、土壤肥力监测库、病虫害监测库等数据库,采用foxPro2.6forWindows程序设计语言编制监测信息管理系统,该系统由站点分布、数据维护、数据浏览、报表生态、统计分析等功能模块构成。在系统软件编制过程中,采用了图文交互支持的信息管理方式,充分利用通用字段(General)的多媒体信息存储功能,且程序运行时可完全脱离foxPro的系统环境,在Windows平台下独立执行。 相似文献
993.
采用内填弹性立体填料的缺氧━好氧固定床生物膜系统处理焦化废水,试验效果良好。当总水力停留时间≥35.2h,COD和NH_3─N的去除率分别这82%和96%以上,出水浓度均达到国家排放标准。 相似文献
994.
Males of the parapatically distributed myobatrachid frogs Geocrinia laevis and G. victoriana have highly divergent advertisement calls. Furthermore, the two species differ strongly in the complexity of their vocal repertoires, with males of G. victoriana possessing, and those of G. laevis lacking, a distinct territorial vocalization (encounter call). We investigated the territorial vocal behavior of males in a persistent natural hybrid population. Most hybrid males possessed encounter calls functionally equivalent to those of G. victoriana, that were produced following exposure to playback of recorded advertisement calls presented at >110 dB peak sound pressure level. The territorial acoustic responses were not associated with an index of hybridity derived from the structure of the advertisement call, suggesting genetic and functional decoupling of the two components of the vocal repertoire; i.e., advertisement calls and encounter calls. This decoupling may be the result of sexual selection favouring those hybrids with pronounced territorial behavior and the associated vocalization, regardless of the structure of their advertisement calls.Communicated by A. Mathis 相似文献
995.
Rimas Žaromskis 《Journal of Coastal Conservation》2007,11(1):23-29
This paper is based on literature-based studies, as well as material collected by the author over more than 30 years on the shores of the Southeast Baltic Sea. In order to protect roads running along the shoreline from East Prussia to Königsberg, local shore reinforcement works commenced in the fifteenth century, although some individual attempts had been made before. In 1684, M. Ch. Hartknoch theoretically substantiated the necessity for, and methods of, shore reinforcement. The state of the shores deteriorated considerably during the Seven Years War (1756–1763), when woodlands growing along the shores were completely destroyed; hence, nearly 100 km length of the coast of the Kur?i? Nerija (Curonian) sand spit was left without any vegetation. Aeolian sand buried as many as fourteen settlements. This situation forced the authorities to organise maintenance of the coast and the dunes at the governmental level, and to start the formation of an uninterrupted dune ridge. The second half of the nineteenth century and the first half of the twentieth century are notable for the extensive construction of new ports. Along the shores running from the Sambian Peninsula to the Gulf of Riga, eight port engineering structures had been constructed with the intervals of approximately 26 km between the ports of Klaip?da and Liepaja, and every 13 km between Palanga and Pape. Shore management measures were being implemented simultaneously, thus ensuring the functioning of the above-mentioned coastal protection structures and the reduction of impacts upon the shores. In the second half of the twentieth century, ports were dredged and developed significantly. Their entrance channels reduced the long-shore sediment transport. Moreover, total sand reserves in the shore zone also diminished. The processes of erosion of the beaches and the dune ridge made it necessary to actively reinforce the shore. A number of countries passed legal acts governing the protection and use of the shore zone. At the turn of the twenty-first century, the incompatibility of such priorities in human activities as sea transport and recreation with nature protection has become evident. The conflict of interests in the Kur?i? Nerija National Park, the port of Klaip?da, and the resort of Palanga serve as good examples of such incompatibility. The conclusion that can be drawn that in twenty-first century is that the priorities in general coastal management should be as follows: harmonisation of interests among the states and individual fields of activities, as well as measures aimed at neutralisation of negative natural trends (higher frequency of storms, global rise of water level, etc.). The protective beach dune ridge will further play the role of efficient means for reducing shore erosion. 相似文献
996.
杀虫双对土壤磷酸酶的毒性效应 总被引:6,自引:0,他引:6
采用模拟方法,对碱性、中性和酸性3类磷酸酶的杀虫双毒性效应进行了研究。结果显示:杀虫双强烈抑制碱性和酸性酶活性,达到了极显著负相关,表明酸性磷酸酶活可表征土壤杀虫双污染的程度;而中性磷酸酶对杀虫双的反应较为迟钝,生态毒性也较弱;不同生态区土壤的酶特征截然不,土和红壤中的主导酶类分别是碱性和酸性磷酸酶,揭示出生态环境对土壤酶特征具有决定性的影响。图2表4参6 相似文献
997.
湖滨带温室气体氧化亚氮(N2O)排放研究 总被引:7,自引:0,他引:7
利用不锈钢气体采集箱,在太湖梅梁湾湖区,沿水体至陆地方向对植被型和裸露型湖滨带进行温室气体N2O的原位排放观测。结果发现两种类型湖滨带N2O排放均显著高于临近的开阔水体,可以达到10~100倍,水位变幅区是湖滨带温室气体N2O排放的峰值区,是陆向和水向辐射区的5~10倍。在观测期间,N2O排放通量的范围为-159.2~1565.6μg·m-2·h-1,具有明显的时空梯度变化,时间上,9月份最高,随着气温的下降和芦苇的衰亡而逐渐减少,在1月份最低;空间上,自水向辐射区至陆向辐射区,先逐渐升高,在水位变幅区达到峰值,然后再降低。该结果初步说明了湖滨带是温室气体N2O的一个极其重要的排放源,而目前IPCC对水体N2O排放的估算可能存在很大的疏漏;同时也从一定程度上反映了湖滨带是湖泊脱氮的重要区域,其对缓解湖泊氮污染起到了举足轻重的作用。 相似文献
998.
以新疆南部孔雀河流域中游地区的尉犁县西尼尔区为例 ,在分析了该区的主要生态环境问题、水资源现状和可用水量的基础上 ,对该区的生态环境建设做出规划。 相似文献
999.
长株潭都市区湘江生态经济带建设 总被引:1,自引:0,他引:1
陈湘满 《城市环境与城市生态》2003,16(4):16-17
都市区作为高密度的人类聚集地,人口与生态环境的矛盾日益突出。都市区生态经济建设显得尤为重要。长株潭都市区3座城市呈“品”字型分布,湘江一水串起3市,建设集旅游观光、生态绿化、科技园区、住宅区和重点小城镇于一体的带状生态经济综合体,即湘江生态经济带,对整个长株潭都市区生态经济建设发挥重要作用。 相似文献
1000.
湖滨带的功能及其管理 总被引:29,自引:1,他引:29
湖滨带是水陆生态交错带的一种类型,具有重要的生态、社会和经济价值。湖滨带功能主要包括:缓冲带功能、生物多样性及生境保护功能、护岸功能和经济美学价值。湖滨带退化的原因主要是人为因素引起的生物群落结构的逆向演替及生态功能的下降,退化湖滨带生态恢复与重建的理论基础是恢复生态学。湖滨带管理的核心是湖滨带植被的正确管理,管理的目标是保护与湖滨带密切相关的各种资源和水生态系统,其管理措施主要包括:(1)建立植被缓冲带;(2)加强湖滨带规划和管理的政策研究;(3)加强湖滨带生态监测系统及生态评价指标体系的建设;(4)促进湖滨带管理的公众参与。 相似文献