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131.
Combating desertification in natural rangelands has recently become a priority in large parts of southern Africa. Rangeland
managers, farmers, scientists, conservationists and land users have been applying a variety of restoration technologies to
address this problem. Bush encroachment, as part of the desertification process, involves the natural replacement of the herbaceous
plant cover by undesirable problem woody species. The active and passive restoration technologies that are applied, are mainly
based on indigenous knowledge and include the chemical, mechanical or manual reclamation of unproductive rangelands, as well
as the combating of woody and alien species encroachment. Indigenous practices and knowledge play a major role in the effectiveness
and success rate of these technologies. This project faces the challenge of bringing together both local and scientific knowledge
in a single user-friendly, computerised Decision Support System (DSS) which is directly accessible by land users to support
them in the process of decision making, concerning the combating of desertification. Case studies from central and northern
Namibia were used to combine qualitative and quantitative data to develop this Decision Support System. The DSS currently
consists of two databases and an expert system, which evaluates the results of land users’ management practices, and provides
easily accessible information and advice for participants in the system, based on the incorporated data. The DSS is also linked
to national and international web sites and databases to offer a wider range of information on technologies concerning agricultural
and conservation practices. 相似文献
132.
A. Haurie J.J.E. Kübler A. Clappier H. van den Bergh 《Environmental Modeling and Assessment》2004,9(1):1-12
A method is proposed to build integrated models (also called Metamodels) aimed at quantifying the economic efficiency of air quality policies. This Metamodeling approach is based on the coupling of two complementary models, that operate at different scales in space and time, and which represent the economic and the physical and chemical processes, respectively. The joint consideration of the physico-chemical and techno-economic structure of the pollution control problems permits a comprehensive evaluation of air pollution abatement strategies. The motivating pollution control problems include urban-regional air quality management through efficient energy and traffic control policies. A pilot study, exploiting data collected in the Geneva canton (Switzerland), is used to demonstrate the potential of the approach. 相似文献
133.
Brock B. Bernstein Rainer Hoenicke Catherine Tyrell 《Environmental monitoring and assessment》1997,48(3):297-306
We present a planning framework that structures thelarge amount of interrelated information involved indeveloping regional monitoring programs. By regionalwe mean programs that recognize the importance ofprocesses that occur on larger geographic scales andthat cut across more than one ecosystem component. Theframework helps visualize functional relationshipsamong qualitative ingredients such as public concernsand more concrete details such as individual dataelements. It portrays the flow of information amongthe components of a regional program and ties eachaspect of the program to management decision-makingneeds. This makes it easier, during the planningprocess, to ensure that monitoring will actuallyproduce useful information. Further, the frameworksnovel, graphically oriented, and readily accessibleformat makes key information equally available to thewide range of participants (regulators, scientists,managers, public) whose input and support arenecessary for program success. 相似文献
134.
Andrew D. Kennedy 《Environmental monitoring and assessment》1997,48(2):173-192
Identifying process from pattern is one of the most vexing tasks inenvironmental monitoring. Given information on the distribution of speciesin a pre-defined area, together with comprehensive data on how environmentalconditions in that area have altered through time, is it possible toidentify the factors controlling the species‘ layout? Here, the practicalsignificance of this quandary is demonstrated using a series ofenvironmentally-degraded coastal lagoons in New South Wales. The TuggerahLakes (33°17′S,151°30′E) have over the last 50 yearsexperienced significant changes in species‘ distributions. Seagrasses,macroalgae, phytoplankton, molluscs, prawns and the jellyfish Catostylus mosaicus have altered in spatial pattern. Two human activitieshave been blamed for these perturbations: (1) agricultural clearance ofnative vegetation from the catchment, with associated input of top-soil andnutrients; (2) the commissioning of a coal-fired power station in 1967, withmassive uptake and recirculation of lake water for cooling purposes. In thispaper, spatial changes in macrophyte distributions over the last 50 yearsare reviewed in an attempt to identify the true source(s) of perturbation.The model adopted assumes that the power station is a point source of impactwhile nutrient inputs from the catchment are a diffuse source of impact;changes in species distributions can hypothetically be related back to thesesources according to whether they are localised or widespread. However,after a comprehensive analysis of available macrophyte data derived frominterviews, aerial photography and line transect methodologyies theconclusion is reached that changes in biogeographical pattern around theTuggerah Lakes cannot be attributed to specific anthropogenic pressures atanything beyond the coarsest of levels. This is considered to be the normfor most coastal management situations where natural background variation(’noise‘) and the complexity of linkages between physical, chemical andbiological components confounds the identification of causal relationships.The practical implications of this conclusion are discussed in the contextof litigation and remedial management design. Emphasis is placed on theneed to adopt an adaptive approach to estuarine management, incorporatingexplicit recognition of the limitations of available data, and to developnew techniques for identifying cause-effect relationships. 相似文献
135.
136.
王新兰 《辽宁城乡环境科技》2006,26(1):21-23
利用污染指数法及相关系数法对盘锦市境内的河、海水质进行对比分析,从而得出近岸海域海湾水质主要受入海河流水质影响的结论。 相似文献
137.
多介质环境目标值的应用 总被引:1,自引:0,他引:1
本文概述了多介质目标德的SAM/Ⅰ的方法。多介质目标值包括环境目标值和排放目标值。点源分析包括SAM/ⅠA,SAM/ⅠB,SAM/Ⅰ,SAM/Ⅱ。在缺少环境质量标准的情况下,使用多介质环境目标值有较强的适用性,且具有省时、省力、经济等特点。本文将多介质目标值的SAM/ⅠA点源分析方法引入聚氯乙烯生产废水的环境评价中,取得较为满意的结果。 相似文献
138.
139.
简要论述中小企业实施ISO 144001标准、建立 环境管理体系面临机遇和挑战,以及中小企业实施ISO 14001标准的对策。 相似文献
140.
环境保护的两种重要手段-政府决策与公众参与 总被引:1,自引:0,他引:1
综述了目前我国环境保护的两种重要手段-政府决策和公众参与的现状及必要性,将政府决策与公众参与结合起来,以推动我国环保事业的进一步发展. 相似文献