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The paper provides an overview of attempts to represent climate change impact in over twenty integrated assessment models (IAMs) of climate change. Focusing on policy optimization IAMs, the paper critically compares modeling solutions, discusses alternatives and outlines important areas for improvement. Perhaps the most crucial area of improvement concerns the dynamic representation of impact, where more credible functional forms need to be developed to express time‐dependent damage as a function of changing socio‐economic circumstances, vulnerability, degree of adaptation, and the speed as well as the absolute level of climate change.  相似文献   

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Because of the importance and complexity of the processes involved in the response of land cover and land use to changing environmental conditions, other approaches are required to evaluate the effectiveness of mitigation options. One such approach is provided by the global integrated assessment model, IMAGE 2. This article presents the structure and some of the underlying assumptions of IMAGE 2, which illustrates the importance of feedback processes in evaluating the effectiveness of mitigation options with respect to land use. Although models such as IMAGE 2 are unsuitable for local and national mitigation evaluations, they can be used to define the regional and global constraints of the smaller scale assessments.  相似文献   

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In dealing with the complex issues of greenhouse gas (GHG) emission and climate change mitigation, many interrelated factors such as cost, level of technology development, supply and demand of energy, structure of industry, and expenditures on research and development exist. Using indicators to monitor environmental impacts and evaluate the efficacies of policies and regulations has been practiced for a long time, and it can serve as a useful tool for decision making and for comparison between different countries. Although numerous indicators have been developed for relevant subjects, integrated approaches that consider individual changes, dynamic interaction, and multi-dimensions of indicators are scarce. This paper aimed to develop a Driving Force-Pressure-State-Impact-Response (DPSIR) framework to assess the problems. This DPSIR model is mainly related to energy consumption, environmental impacts, and policy responses. The objectives of the paper were: (1) conduct a literature review on the indicators that have been used in GHG-related studies; (2) develop a DPSIR model that incorporates GHG-related indicators and evaluate their relationships using a cause?Ceffect chain of GHG emission; and (3) develop a calculative method that can be used to explain the dynamic correlation among the interdependent indicators. Taiwan is a significant source of global GHG emissions. A case study, using the developed framework and Taiwan??s actual data of the past two decades, was conducted. The results indicate that regulatory strategies for pollution control are inadequate in terms of ensuring environmental quality, and the nature does not have the capability to revert the impacts from the existing level of pollution.  相似文献   

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Increasing nitrogen (N) immobilization and weed interference in the early phase of implementation of conservation agriculture (CA) affects crop yields. Yet, higher fertilizer and herbicide use to improve productivity influences greenhouse gase emissions and herbicide residues. These tradeoffs precipitated a need for adaptive N and integrated weed management in CA-based maize (Zea mays L.)—wheat [Triticum aestivum (L.) emend Fiori & Paol] cropping system in the Indo-Gangetic Plains (IGP) to optimize N availability and reduce weed proliferation. Adaptive N fertilization was based on soil test value and normalized difference vegetation index measurement (NDVM) by GreenSeeker? technology, while integrated weed management included brown manuring (Sesbania aculeata L. co-culture, killed at 25 days after sowing), herbicide mixture, and weedy check (control, i.e., without weed management). Results indicated that the ‘best-adaptive N rate’ (i.e., 50% basal + 25% broadcast at 25 days after sowing + supplementary N guided by NDVM) increased maize and wheat grain yields by 20 and 14% (averaged for 2 years), respectively, compared with whole recommended N applied at sowing. Weed management by brown manuring (during maize) and herbicide mixture (during wheat) resulted in 10 and 21% higher grain yields (averaged for 2 years), respectively, over the weedy check. The NDVM in-season N fertilization and brown manuring affected N2O and CO2 emissions, but resulted in improved carbon storage efficiency, while herbicide residuals in soil were significantly lower in the maize season than in wheat cropping. This study concludes that adaptive N and integrated weed management enhance synergy between agronomic productivity, fertilizer and herbicide efficiency, and greenhouse gas mitigation.  相似文献   

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A large number of studies on the reclamation of mine soils focused on the problem caused by metals and did not explore in depth the issue of nutrients and vegetation after the application of organic materials. The aim of this study was to compare the effect of two treatments made of wastes and vegetated with Brassica juncea L. on the fertility of a settling pond mine soil. The first treatment was compost, biochar, and B. juncea (SCBP) and the second treatment was technosol, biochar, and B. juncea (STBP). This study evaluated the effect of the treatments on the soil nutrient concentrations and fertility conditions in the soil amendment mixtures, after 11 months of greenhouse experiment. Total carbon and nitrogen concentrations were higher in treatment SCBP than in treatment STBP after 7 months but, after 11 months, carbon concentration was higher in STBP. The used technosol could have forms of carbon more stable than compost, which could be released slower than in the compost-amended soils. Both compost and technosol mixed with biochar also increased the concentration of calcium, potassium, magnesium, and sodium in exchangeable form in the mine soil.  相似文献   

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Mathematical models are utilized to approximate various highly complex engineering, physical, environmental, social, and economic phenomena. Model parameters exerting the most influence on model results are identified through a sensitivity analysis. A comprehensive review is presented of more than a dozen sensitivity analysis methods. This review is intended for those not intimately familiar with statistics or the techniques utilized for sensitivity analysis of computer models. The most fundamental of sensitivity techniques utilizes partial differentiation whereas the simplest approach requires varying parameter values one-at-a-time. Correlation analysis is used to determine relationships between independent and dependent variables. Regression analysis provides the most comprehensive sensitivity measure and is commonly utilized to build response surfaces that approximate complex models.  相似文献   

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Though the principles of the Earth's greenhouse effect have been known for well over a century, it is only recently that advances in climate research have indicated that significant and possibly costly climate change, due to growing emissions of greenhouse gases and their precursors by human activity, is a real possibility. Current estimates of the global human-related emissions of carbon dioxide, methane and nitrous oxide are presented, though many sources remain poorly known or understood. The compilation of national greenhouse inventories as required by the United Nations Framework Convention on Climate Change is likely in the longer term to help improve such global estimates, as long as comparable methodologies are used. The development of the IPCC Guidelines for National Greenhouse Gas Inventories is described, emphasizing the strategies employed to gain wide international participation.  相似文献   

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Modern ecological state of the World Oceans is analysed, stressing the need for organization and development of a scientific basis for global ocean monitoring. The tasks and basic principles of integrated global ocean monitoring are described.Complex of natural processes determines the assimilative capacity of marine ecosystems, which can serve as a basis for the study of ecological reserves of the World Oceans and ecological rationing of the anthropogenic impact.  相似文献   

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The Gambia has successfully completed a national greenhouse gas emissions inventory based on the results of a study funded by the United Nations Environment Programme (UNEP)/Global Environment Facility (GEF) Country Case Study Program. The concepts of multisectoral, multidisciplinary, and interdisciplinary collaboration were most useful in the preparation of this inventory. New data were gathered during the study period, some through regional collaboration with institutions such as Environment and Development in the Third World (ENDA-TM) Energy Program and the Ecological Monitoring Center in Dakar, Senegal, and some through national surveys and the use of remote sensing techniques, as in the Bushfires Survey. Most of the data collected are used in this paper. The Intergovernmental Panel on Climate Change/Organisation for Economic Co-operation and Development/International Energy Agency (IPCC/OECD/IEA) methodology is used to calculate greenhouse gas emissions. Many of the default data in the IPCC/OECD/IEA methodology have also been used. Overall results indicate that in the biomass sectors (agriculture, forestry, and land-use change) carbon dioxide (CO2) is emitted most, with a total of 1.7 Tg. This is followed by methane (CH4), 22.3 Gg; carbon monoxide (CO), 18.7 Gg; nitrogen oxides (NOx), 0.3 Gg; and nitrous oxide (N2O), 0.014 Gg. The Global Warming Potential (GWP) was used as an index to describe the relative effects of the various gases reported here. Based on the emissions in The Gambia in 1993, it was found that CO2 will contribute 75%, CH4 about 24.5%, and N2O 0.2% of the warming expected in the 100-year period beginning in 1993. The results in this analysis are limited by the shortcomings of the IPCC/OECD/IEA methodology and scarce national data. Because the methodology was developed outside of the developing world, most of its emissions factors and coefficients were developed and tested in environments that are very different from The Gambia. This is likely to introduce some uncertainties into the results of the calculations. Factors and coefficients that are country-or region-specific are likely to provide more accurate results and should be developed. The surveys were conducted either during the wet season or just at the end of the wet season. This seasonal factor should contribute to variations in the results, particularly in the livestock numbers and composition survey. Use of one-time survey data is also likely to introduce uncertainty into the results.  相似文献   

12.
A simple model has been designed to describe the interaction of climate and biosphere. Carbon dioxide, understood as a major emitted gas, leads to a change of global climate. Economic interpretation of the model is based on the maximisation of the global CO2 cumulative emissions. The two most important profiles of emission have been obtained: optimal and multi-exponential suboptimal profiles, each displaying different characteristics. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

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Starting with the intensification of irrigation activities in the beginning of 1980s in Abaya and Chamo lakes area, the decreasing water inflow to the lakes caused denudation of the wetlands. The ecological situation in the lake region changed significantly during last four decades. The lakes and associated wetlands change have been studied using Landsat MSS (1973), Landsat TM (1986), and Ladsat ETM (2000) satellite imagery. Along with satellite imagery, other hydro-meteorological data were collected and hydro-meteorological data analyses were done to assess the variability of wetlands. From these data, lakes morphometric property estimation at different time series and water balance analysis for both lakes were done. Wetlands are mapped from the TCT image and these maps are subject to change detection to see the temporal and spatial variability of the wetlands. Moreover, the lake-morphometric area and volume variation have been studied. The result showed that between 1986 and 2000, a significant reduction has been observed but lesser than the previous decades (6.4 km(2)). The identified reason behind this change is that the free settlement and shoreline cultivation of the wetlands causing the soil erosion and eventually adds the sediment to the wetlands.  相似文献   

16.
The aim of this study is to research natural land cover change caused by the permanent effects of human activities in Duzce plain and its surroundings, and to determine the current status of the land cover. For this purpose, two Landsat TM images were used in the study for the years 1987 and 2010. These images are analysed by using data image processing techniques in ERDAS Imagine©10.0 and ArcGIS©10.0 software. Land cover change nomenclature is classified according to the Coordination of Information on the Environment Level 2 Classification (1—urban fabric, 2—industrial, commercial and transport units, 3—heterogeneous agricultural areas, 4—forests, and 5—inland wetlands). Furthermore, the image analysis results are confirmed by the field research. According to the results, a decrease of 33.5 % was recorded in forest areas from 24,840.7 to 16,529.0 ha; an increase of 11.2 % was recorded in heterogeneous agricultural areas from 47,702.7 to 53,051.7 ha. Natural vegetation, which is the large part of land cover in the research area, has been changing rapidly because of rapid urbanisation and agricultural activities. As a result, it is concluded that significant changes have occurred on the natural land cover between the years 1987 and 2010 in the Duzce plain and its surroundings.  相似文献   

17.
城市环境信息综合查询分析系统开发与应用实践   总被引:4,自引:0,他引:4  
主要介绍了城市环境信息综合查询分析系统的建设目标、体系结构、数据组织、系统模块的功能、关键技术等.应用实践表明,开放的体系结构、通用的GIS平台,一体编码的数据库管理技术,规范标准的信息维护与评价体系等可为开发其它城市的环境信息系统提供借鉴.  相似文献   

18.
Agent-based integrated assessment modelling: the example of climate change   总被引:1,自引:0,他引:1  
Current approaches to deal with the socio-economic implications of climate change rely heavily on economic models that compare costs and benefits of different measures. We show that the theoretical foundations underpinning current approaches to economic modelling of climate change are inappropriate for the type of questions that are being asked. We argue therefore that another tradition of modelling, social simulation, is more appropriate in dealing with the complex environmental problems we face today.  相似文献   

19.
How to assess the potential habitat integrating landscape dynamics and population research, and how to reintroduce animals to potential habitats in environments highly human disturbed are still questions to be answered in conservation biology. According to behavioral research on Elaphurus davidians, we have developed a suitability index and a risk index to evaluate the potential habitats for the deer. With these indices, we conducted two transect assessments to evaluate the gradient change of the target region. Then, taking rivers as border lines, we tabulated the forest areas, high grassland area and total area and then compared the forest and high grassland area in each subregion. Furthermore, we computed the land use transfer matrix for the whole Yancheng coast during 1987-2000. We also computed human modified index (HMI) in six subregions. Lastly with a geographical information system support we obtained the spatial distribution of the indices and evaluation of the whole potential habitats from a neighborhood analysis. The transect assessment showed that the suitability of the coastal area was higher than that of the inland area for the deer, while the southern area was higher than the northern. Landscape metrics and HMI analysis showed that different landscape patterns and different anthropogenic disturbance existed within the region, and the increasing human disturbance was the key factor causing the pattern dynamics. The evaluation of potential habitats showed that there was an estimated carrying capacity of no more than 10,000 for David's deer reintroduction into the natural area. Also the reintroduction strategy was discussed. This integrated approach linked the population research and the landscape metrics, and the dataset with different scale; thus, it is an approach likely to be useful for the protection of other large animal in a landscape highly disturbed by humans.  相似文献   

20.
The effect of humic acids on the sequential extraction of metals from various soils and sediments has been studied. A new multi-element extraction method optimised via experimental design has been employed. The method uses centrifugation to pass the extractant solution, at varying pH, through the sediment sample. The sequential leaches were collected and analysed by ICP-AES. Chemometric data processing was utilised to identify the composition of the physico-chemical components in order to characterise the sample. A sediment sample collected from Carnon River (Cornwall, UK) and a reference material (NIST 2711 agricultural soil) were spiked with humic acids and the sequential extraction scheme was used to monitor the changes in metal distribution. The method has proved a quick and reliable way to evaluate different sediment samples, and has potential as a new tool for environmental geochemistry analysis.  相似文献   

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