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501.
Zak Le Roux 《The Environmentalist》1993,13(2):105-110
Summary The objectives, appropriate strategies, the state of conservation in South Africa, and the contributed research which is needed, are evaluated. It is suggested that the ultimate objectives of conservation are to maintain the ecosystem to support people and to achieve economic advantages. These can only be obtained by providing for the greatest possible diversity of life on Earth. An appropriate conservation strategy can be based on a balanced combination of five types of conservation opportunities. These opportunities are: (i) formal conservation in reserves, (ii) promotion of land use change for conservation, (iii) law enforcement, (iv) national resource utilisation planning, and (v) the development of a national land ethic. Adjustment of the opportunity combination to address changing threast must be an ongoing exercise. Conservation strategies need to be based on sound conceptual models of ecosystem structure and function, as well as human needs and aspirations. The main goals of the conservation ecologist are the development, testing and validation of conceptual models of ecosystems.Mr Zak Le Roux is employed in the Scientific Services Section of the Ecosystem Conservation Department of the Natal Parks Board. He possesses a BSc in Forestry and Nature Conservation from the University of Stellenbosch, and is currently undertaking research in Plant Ecology at the University of Natal. A tenth generation South African, his work focuses on vegetation dynamics of semi-arid savanna landscapes and general conservation in Zululand. In particular, this involves the integration of wildlife with agriculture, and the development of more appropriate land uses in the areas surrounding the parks. 相似文献
502.
Gall M 《Disasters》2004,28(1):82-97
This paper, through spatial-analysis techniques, examines the accessibility of emergency shelters for vulnerable populations, and outlines the benefits of an extended and permanently established shelter network in central Mozambique. The raster-based modelling approach considers data on land cover, locations of accommodation centres in 2000, settlements and infrastructure. The shelter analysis is a two-step process determining access for vulnerable communities first, followed by a suitability analysis for additional emergency shelter sites. The results indicate the need for both retrofitting existing infrastructure (schools, health posts) to function as shelters during an emergency, and constructing new facilities - at best multi-purpose facilities that can serve as social infrastructure and shelter. Besides assessing the current situation in terms of availability and accessibility of emergency shelters, this paper provides an example of evaluating the effectiveness of humanitarian assistance without conventional mechanisms like food tonnage and number of beneficiaries. 相似文献
503.
Banks D Adam AM Bayliss V Hogg GM Bleuten W Dees M Karnachuk OV Le Blansch K Marquand J 《Environmental management》2000,26(1):35-46
/ Implementation of environmental management in Russia is undergoing rapid changes. Federal responsibility rests with the Russian Federation State Committee for Environmental Protection (RFSCEP) and is delegated at regional level to local State Committees for Environmental Protection (SCEPs). This paper focuses on the functioning of the SCEP for Tomsk oblast' (region) in Siberia, which is strongly committed to forging constructive links with regional government, academia, industry, and environmental NGOs. Considerable difficulties exist for SCEPs in Russia, however, and prominent among these are (1) a rigidly vertical civil service structure, with separate organs having responsibility for different natural resources, persisting from Soviet times, which hinders effective intergrated and holistic environmental management; and (2) a lack of open access to environmental information from military and quasi-military sites. 相似文献
504.
Ribeiro IC Veríssimo I Moniz L Cardoso H Sousa MJ Soares AM Leão C 《Chemosphere》2000,41(10):1637-1642
In the present work the sensitivity of yeast strains of Kluyveromyces marxianus, Pichia anomala, Candida utilis, Schizosaccharomyces pombe and Saccharomyces cerevisiae, to the fungicides cymoxanil, penconazol, and dichlofluanid, was evaluated. Dichlofluanid induced the most negative effects, whereas penconazol in general was not very toxic. Overall, our results show that the parameters IC50 for specific respiration rates of C. utilis and S. cerevisiae and C(D) for cell viability of S. cerevisiae can be applied to quantify the toxicity level of the above compounds in yeast. Hence, could be explored as an alternative or at least as a complementary test in toxicity studies and, therefore, its potential for inclusion in a tier testing toxicity test battery merits further research. 相似文献
505.
Josefina León-Félix Rosa A. Martínez-Bustillos Manuel Báez-Sañudo Felipe Peraza-Garay Cristóbal Chaidez 《Food and environmental virology》2010,2(4):211-217
To evaluate the impact of harvesting and packinghouse operation on the contamination of green bell pepper (GBP) with viruses
and enteric bacteria. Hands of 97 workers plus 40 GBP were sampled from field and packinghouse areas. RT-nested PCR were used
for the identification of Noroviruses (NV) and Chromogenic agar for the quantification of coliforms and Escherichia coli. NV was found in 30.9 and 23.7% of workers’ hands, before and after 3 h of work, respectively, while 45 and 30% of field
and packed GBP was positive for NV. Fecal coliforms and Escherichia coli were present in 68 and 57.3% and 12.4 and 11.1% of workers’ hands before and after 3 h of work, respectively. Fecal coliforms
were detected in 85 and 15% of field and packed GBP, respectively, while E. coli was absent. There was no significant correlation between bacterial indicator and NV in the analyzed samples (P > 0.05). Handling of fresh produce by workers during harvesting and packing operations has negative impacts on fresh produce
safety. 相似文献
506.
Haifa Maalouf Monique Pommepuy Françoise S. Le Guyader 《Food and environmental virology》2010,2(3):136-145
Human fecal wastes contain a large variety of viruses that can enter the environment through discharge of waste materials from infected individuals. Despite the high diversity of viruses that are introduced into the environment by human fecal pollution, only a few have been recognized to cause disease in association with consumption of contaminated shellfish. To explain bivalve mollusks contamination, several factors including human epidemiology, virus persistence through sewage treatment plant, and shellfish uptake may be suggested. Considering different outbreaks described in the literature, the most common route for transmission is accidental contamination after heavy rainfall, when extra loads cause an overflow, and release of untreated sewage into the aquatic environment. Outbreak analysis also demonstrates the impact on shellfish consumption of some viral strain transmission and thus their impact on molecular epidemiology, especially for norovirus. To limit shellfish contamination and thus to protect the consumer, the most desirable and effective option is to reduce the viral input. 相似文献
507.
Å. Eliasson R.J.A. Jones F. Nachtergaele D.G. Rossiter J.-M. Terres J. Van Orshoven H. van Velthuizen K. Böttcher P. Haastrup C. Le Bas 《Environmental Science & Policy》2010,13(8):766-777
This article defines eight key climate, soil and terrain criteria that have been developed for the future delimitation of the Intermediate Less Favoured Areas (LFAs) support, a measure of the Common Agricultural Policy. The LFA scheme has existed since 1975 and is a broad mechanism for improving the viability of agriculture in areas with natural handicaps. The common criteria have been developed for the European Commission's Directorate-General for Agriculture and Rural Development to satisfy the objectives in the Rural Development Policy 2007–2013 (Axis II), which aim to improve the environment and the countryside by more sustainable land management. The criteria were developed by experts, coordinated by the European Commissions Joint Research Centre, to meet the requirement for a robust and harmonised approach of identifying areas that experience natural constraints to agriculture throughout the EU 27 Member States. The criteria proposed are: temperature, heat stress, drainage, soil texture and stoniness, soil rooting depth, soil chemical properties, soil moisture balance and slope. Each criterion is described and an indicative threshold for assessment of its impact on agriculture is provided. The criteria are currently being tested by the EU Member States for a future possible legislation. 相似文献
508.
509.
基于Web-GIS的环境空气自动监测系统研究 总被引:1,自引:0,他引:1
为使空气自动监测技术更加完善,实现以环境空气实时监控为主的各项基础信息的快速查询、统计、分析,建立基于浏览器/服务器模式的采用W eb-G IS技术的空气自动监测系统,采用数据库、中间层服务器和浏览器组成的三层体系结构。导入鞍山市城区电子地图,实现各监测子站、各污染物及各气象参数的图形动态演示,直观地表现子站及周边污染源分布及污染物监测浓度的动态变化,实现了环境空气污染的空间信息、属性信息的综合管理。 相似文献
510.