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11.
    
Conserving freshwater habitats and their biodiversity in the Amazon Basin is a growing challenge in the face of rapid anthropogenic changes. We used the most comprehensive fish-occurrence database available (2355 valid species; 21,248 sampling points) and 3 ecological criteria (irreplaceability, representativeness, and vulnerability) to identify biodiversity hotspots based on 6 conservation templates (3 proactive, 1 reactive, 1 representative, and 1 balanced) to provide a set of alternative planning solutions for freshwater fish protection in the Amazon Basin. We identified empirically for each template the 17% of sub-basins that should be conserved and performed a prioritization analysis by identifying current and future (2050) threats (i.e., degree of deforestation and habitat fragmentation by dams). Two of our 3 proactive templates had around 65% of their surface covered by protected areas; high levels of irreplaceability (60% of endemics) and representativeness (71% of the Amazonian fish fauna); and low current and future vulnerability. These 2 templates, then, seemed more robust for conservation prioritization. The future of the selected sub-basins in these 2 proactive templates is not immediately threatened by human activities, and these sub-basins host the largest part of Amazonian biodiversity. They could easily be conserved if no additional threats occur between now and 2050.  相似文献   
12.
This paper demonstrates the ability of Polish agriculture to adapt to predicted climate change according to GISS and GFDL scenarios. Both climate-change scenarios will significantly affect farming conditions in Poland through water deficit, shifts in planting and harvesting seasons, changes in crop yields and crop structure. Neither scenario seems to endanger the self-sufficiency of Poland as long as preventative measures are taken. Moreover, the realization of GISS creates the possibility of a surplus in production. It must be emphasized that regardless of the scenario, the adaptation of agriculture to an expected climate change cannot be handled by the farming community itself.  相似文献   
13.
为提高用驾驶人危险辨识能力评估系统得到的评估结果的信效度,探讨评估场景对评估结果的影响。首先,分析各类评估系统中评估场景的异同点;其次,由于评估场景一般为危险情境,通过对危险定义与类型、危险风险度的系统梳理,探讨危险情境对评估结果的影响;最后,通过分析动静态场景的优缺点,探讨场景展现形式对评估结果的影响。结果表明:危险情境的主观和客观风险度的一致性越高,评估结果的信效度越好;动静态场景各有利弊,静态场景能有效避免评估结果的模糊性和驾驶人的疲劳厌烦效应,动态场景更利于理解危险情境,同时更贴近驾驶人实际驾驶时的危险辨识工作机制。  相似文献   
14.
Modeling of non-point source pollution in a Mediterranean drainage basin   总被引:2,自引:0,他引:2  
SWAT ver. 2000 was used to predict hydrographs, and sediment, nitrate and total phosphorus loadings from a 1349 km2 mountainous/agricultural watershed in Northern Greece. The model was calibrated and verified using continuous meteorological data from eight stations within the drainage area, and runoff, sediment and nutrient concentrations measured at nine stations located within the main tributaries of the watershed, for the time period from May 1st, 1998 to January 31st, 2000. Model validation methodology and resulting input parameters appropriate for Mediterranean drainage basins are presented. Predicted by the model hydrographs, sedimentographs and pollutographs are plotted against observed values and show good agreement. Model performance is evaluated using the root mean square error computation and scattergrams of predicted versus observed data. The validated model is also used to test the effectiveness of three alternative cropping scenarios in reducing nutrient loadings from the agricultural part of the watershed. The study showed that this model, if properly validated, can be used effectively in testing management scenarios in Mediterranean drainage basins.  相似文献   
15.
Air pollution Integrated Assessment Models (IAM) can be used for determining how emissions should be reduced to improve air quality and to protect human health in a cost-efficient way. The application of IAM is also useful to spread information to the general public and to explain the effectiveness of proposed Air Quality Plans. In this paper, the application of the RIAT+ system to determine suitable abatement measures to improve the air quality at a regional/local level is presented for two European cases: the Brussels Capital Region (Belgium) and the Porto Urban Area (Portugal). Both regions are affected with PM10 or NO2 concentrations that exceed the limit values specified by the European Union legislation. To properly assess air quality abatement measures a surrogate model was used, allowing the implementation of an efficient optimization procedure. This model is derived in both cases through a set of simulations performed using a Chemistry Transport Model fed with different emission reduction scenarios. In addition, internal costs (due to the implementation of emission reduction measures) and external costs (due to population exposure to air pollutant concentrations) of policy options were considered. The application of this integrated assessment modelling system in scenario (Brussels case) and optimization (Porto) modes contributes to identifying some advantages and limitations of these two approaches and also provides some guidance when urban air quality has to be assessed.  相似文献   
16.
Acid rain in Asia   总被引:3,自引:0,他引:3  
Acid rain has been an issue of great concern in North America and Europe during the past several decades. However, due to the passage of a number of recent regulations, most notably the Clean Air Act in the United States in 1990, there is an emerging perception that the problem in these Western nations is nearing solution. The situation in the developing world, particularly in Asia, is much bleaker. Given the policies of many Asian nations to achieve levels of development comparable with the industrialized world—which necessitate a significant expansion of energy consumption (most derived from indigenous coal reserves)—the potential for the formation of, and damage from, acid deposition in these developing countries is very high. This article delineates and assesses the emissions patterns, meteorology, physical geology, and biological and cultural resources present in various Asian nations. Based on this analysis and the risk factors to acidification, it is concluded that a number of areas in Asia are currently vulnerable to acid rain. These regions include Japan, North and South Korea, southern China, and the mountainous portions of Southeast Asia and southwestern India. Furthermore, with accelerated development (and its attendant increase in energy use and production of emissions of acid deposition precursors) in many nations of Asia, it is likely that other regions will also be affected by acidification in the near future. Based on the results of this overview, it is clear that acid deposition has significant potential to impact the Asian region. However, empirical evidence is urgently needed to confirm this and to provide early warning of increases in the magnitude and spread of acid deposition and its effects throughout this part of the world.  相似文献   
17.
Abstract: For over 10 years, several species of salmon have been identified as either threatened or endangered in the Snake River Basin of Idaho. The United States Bureau of Reclamation, in cooperation with the National Marine Fisheries Service, has proposed a variety of plans to increase stream flows in the Snake River Basin to facilitate movement by juvenile salmon smolts to the ocean. This research examines two of the flow augmentation plans proposed by the Bureau of Reclamation as well as two alternative plans, one founded purely on existing priority‐based water rights and another geared toward minimizing the effects of flow augmentations on farms profitability. Results from a basin‐wide model of agricultural production in the Snake River Basin, the Snake River Agricultural Model, present evidence that (1) older water rights are used towards production of less valuable crops, (2) flow augmentation scenarios have unequal effects on farms profitability across agricultural regions within the basin, and (3) irrigation water is valued from US$4 to US$59 an acre‐foot.  相似文献   
18.
    
This paper describes a Delphi methodology to generate a number of broadly consensual low carbon scenarios for 2050. This approach to ‘creating’ the future, rather than predicting, is useful when dealing with profound and uncertain change over a long period of time and is therefore suited to carbon management. The methodology is described, and the first stage of the consultation process is discussed with reference to its application in the UK city region of Bristol. Findings from the first round have resulted in the identification of seven working scenarios and patterns in the responses of individuals from different backgrounds, suggesting that strong world-views and agendas are present within groups. Subsequent rounds of a questionnaire and a backcasting workshop will refine these working scenarios and identify pathways to achieve them.  相似文献   
19.
    
Planning for the deployment of carbon dioxide capture and storage (CCS), infrastructure must consider numerous uncertainties regarding where and how much CO2 is produced and where captured CO2 can be geologically stored. We used the SimCCS engineering‐economic geospatial optimization models to determine the characteristics of CCS deployment in France and corridors for pipelines that are robust to a priori uncertainty in CO2 production from industrial sources and CO2 storage locations. We found a number of stable routes that are robust to these uncertainties, and thus can provide early options for pipeline planning and rights‐of‐way acquisition.  相似文献   
20.
The applications of chlorine have been broadly used in many industrial products, such as bleaching agents, synthetic rubbers, plastics, disinfectants, iron chlorides, fire refractory materials, insecticides, and anti-freezers, etc. According to the Taiwan Environmental Protection Administration (TEPA), more than 30 thousand tons were used in the year 2000. In addition, there were more than 12 reported incidents from 2000 to 2003—mostly on using chlorine as disinfectants (five) and as process agents (four).

This study investigated 15 chlorine operation plants in central Taiwan. These chlorine usages included bleaching agents, disinfectants, iron chloride, synthesizing rubber plastics, and others. Thirteen plants were located in the industrial parks and two were in or near residential zones. The consequence analysis were used three different methods to analyze the worst-case scenarios (WCSs) and alternative release case scenarios (ACSs) in order to compare impact zones for applying various active and passive mitigation systems, such as confined space, scrubber, water-spray, and so no. For two plants in or near residential zones, multi-layers mitigation systems and operation limits should be implemented in order to enforce more stringent protection measures. However, there was no specific regulation for chlorine plants operated at different locations, such as industrial parks or residential zones. In order to reduce chemical accidents and their impacts on public safety, our results suggest that source mitigation/management and warning systems should be adopted simultaneously.  相似文献   

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