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排序方式: 共有482条查询结果,搜索用时 323 毫秒
1.
为了分析影响矿工不安全行为决策的成本收益因素,扩展不安全行为的研究方向,基于行为经济学,构建矿工不安全行为决策模型,模型包括矿工属性、管理者属性以及矿工之间的交互影响规则。利用Netlogo工具进行仿真模拟,探讨不同影响因素对不安全行为产生的影响程度。结果表明:正向激励水平对抑制不安全行为效果显著,同时,维持合理的工作时间对保障安全生产意义重大,从而为煤矿企业控制不安全行为提供思路。  相似文献   
2.
中国经济增长对碳排放的影响分析   总被引:44,自引:1,他引:43  
通过相关分析探讨了中国国内生产总值(GDP)的增长与碳排放量的关系.结果表明,二者有明显的相关性(R2=0.958 1).进一步研究认为,由于中国投资率在35%~40%以上,且工业增加值占GDP的比重超过50%,因此中国过分依赖投资的经济增长方式和以第二产业(工业)为主的经济结构在很大程度上是导致温室气体排放量增加的主要原因.未来在全球化背景下,经济增长可转变为更多地依靠科技创新、技术进步和制度的改进,因此,调整经济增长方式和产业结构,可以在保持发展经济的同时,使碳排放强度呈逐渐下降的趋势.  相似文献   
3.
International cooperation to address climate change now stands at a crossroads.With a new international regime for emissions reduction established by the Durban Platform, "New Climate Economics(NCE)" has become a research hotspot.The need for urgent action to combat climate change has prompted discussion on reforms of economic growth patterns and the energy system.The industrial civilization,therefore,now faces a transition towards a new pathway for ecological sustainability.NCE explores new economic concepts,theories,and analytical methods to design a balanced pathway for sustainable growth and emission reduction.Instead of getting trapped in discussions on allocation of emission reduction responsibilities and obligations among countries,NCE pays more attention to developing win-win multilateral cooperation mechanisms that facilitate collaborative RD and knowledge sharing.In addition,NCE studies incentives for low-carbon transition,turning carbon emission reduction into a domestic need for countries to increase their international competitiveness.To achieve the 2°C target,most countries around the world face challenges of insufficient emission allowances to cover expected emissions associated with their projected economic growth.As carbon emissions rights becomes an increasingly scarce resource,increasing the carbon productivity of the economy turns to be the critical path to address the dilemma of green or growth.NCE studies the historical evolution of carbon productivity for countries at different development stages as well as ways to enhance such carbon productivity.This type of study provides invaluable lessons for emerging economies to reach their own emission peaks without losing the momentum of growth.Replacing fossil fuels with new and renewable energy has proven to be an inevitable choice for reshaping the energy system and addressing climate change- it has already become a global trend.NCE studies incentives for new energy technology innovation and deployment provided by carbon pricing,and sheds light on the co-benefits of climate change mitigation,such as resource conservation,environmental protection,and energy security.The role of carbon pricing in promoting intemational RD cooperation and technical transfer will also be studied.The shift in consumption patterns is another key factor enabling a low-carbon transformation.Therefore,NCE also explores the theoretical work on new values of wealth,welfare and consumption,new lifestyles in the context of ecological civilization,concepts and implementation of low-carbon urban planning in developing countries,and the impacts of consumption pattern changes on social development,material production,and urban infrastructure construction.  相似文献   
4.
We study a dynamic common pool resource game in which current resource stock depends on resource extraction in the previous period. Our model shows that for a sufficiently high regrowth rate, there is no commons dilemma: the resource will be preserved indefinitely in equilibrium. Lower growth rates lead to depletion. Laboratory tests of the model indicate that favorable ecological characteristics are necessary but insufficient to encourage effective CPR governance. Before the game, we elicit individual willingness to follow a costly rule. Only the presence of enough rule-followers preserves the resource given favorable ecological conditions.  相似文献   
5.
Between 1990 and 2007, 15 southern white (Ceratotherium simum simum) and black (Diceros bicornis) rhinoceroses on average were killed illegally every year in South Africa. Since 2007 illegal killing of southern white rhinoceros for their horn has escalated to >950 individuals/year in 2013. We conducted an ecological–economic analysis to determine whether a legal trade in southern white rhinoceros horn could facilitate rhinoceros protection. Generalized linear models were used to examine the socioeconomic drivers of poaching, based on data collected from 1990 to 2013, and to project the total number of rhinoceroses likely to be illegally killed from 2014 to 2023. Rhinoceros population dynamics were then modeled under 8 different policy scenarios that could be implemented to control poaching. We also estimated the economic costs and benefits of each scenario under enhanced enforcement only and a legal trade in rhinoceros horn and used a decision support framework to rank the scenarios with the objective of maintaining the rhinoceros population above its current size while generating profit for local stakeholders. The southern white rhinoceros population was predicted to go extinct in the wild <20 years under present management. The optimal scenario to maintain the rhinoceros population above its current size was to provide a medium increase in antipoaching effort and to increase the monetary fine on conviction. Without legalizing the trade, implementing such a scenario would require covering costs equal to approximately $147,000,000/year. With a legal trade in rhinoceros horn, the conservation enterprise could potentially make a profit of $717,000,000/year. We believe the 35‐year‐old ban on rhinoceros horn products should not be lifted unless the money generated from trade is reinvested in improved protection of the rhinoceros population. Because current protection efforts seem to be failing, it is time to evaluate, discuss, and test alternatives to the present policy.  相似文献   
6.
Conservation decision makers commonly use project‐scoring metrics that are inconsistent with theory on optimal ranking of projects. As a result, there may often be a loss of environmental benefits. We estimated the magnitudes of these losses for various metrics that deviate from theory in ways that are common in practice. These metrics included cases where relevant variables were omitted from the benefits metric, project costs were omitted, and benefits were calculated using a faulty functional form. We estimated distributions of parameters from 129 environmental projects from Australia, New Zealand, and Italy for which detailed analyses had been completed previously. The cost of using poor prioritization metrics (in terms of lost environmental values) was often high—up to 80% in the scenarios we examined. The cost in percentage terms was greater when the budget was smaller. The most costly errors were omitting information about environmental values (up to 31% loss of environmental values), omitting project costs (up to 35% loss), omitting the effectiveness of management actions (up to 9% loss), and using a weighted‐additive decision metric for variables that should be multiplied (up to 23% loss). The latter 3 are errors that occur commonly in real‐world decision metrics, in combination often reducing potential benefits from conservation investments by 30–50%. Uncertainty about parameter values also reduced the benefits from investments in conservation projects but often not by as much as faulty prioritization metrics.  相似文献   
7.
Conservation easements are a standard technique for preventing habitat loss, particularly in agricultural regions with extensive cropland cultivation, yet little is known about their effectiveness. I developed a spatial econometric approach to propensity‐score matching and used the approach to estimate the amount of habitat loss prevented by a grassland conservation easement program of the U.S. federal government. I used a spatial autoregressive probit model to predict tract enrollment in the easement program as of 2001 based on tract agricultural suitability, habitat quality, and spatial interactions among neighboring tracts. Using the predicted values from the model, I matched enrolled tracts with similar unenrolled tracts to form a treatment group and a control group. To measure the program's impact on subsequent grassland loss, I estimated cropland cultivation rates for both groups in 2014 with a second spatial probit model. Between 2001 and 2014, approximately 14.9% of control tracts were cultivated and 0.3% of treated tracts were cultivated. Therefore, approximately 14.6% of the protected land would have been cultivated in the absence of the program. My results demonstrate that conservation easements can significantly reduce habitat loss in agricultural regions; however, the enrollment of tracts with low cropland suitability may constrain the amount of habitat loss they prevent. My results also show that spatial econometric models can improve the validity of control groups and thereby strengthen causal inferences about program effectiveness in situations when spatial interactions influence conservation decisions.  相似文献   
8.
Ground and surface water selenium (Se) contamination is problematic throughout the world, leading to harmful impacts on aquatic life, wildlife, livestock, and humans. A groundwater reactive transport model was applied to a regional‐scale irrigated groundwater system in the Lower Arkansas River Basin in southeastern Colorado to identify management practices that remediate Se contamination. The system has levels of surface water and groundwater Se concentrations exceeding the respective chronic standard and guidelines. We evaluate potential solutions by combining the transport model with an assessment of the cost to employ those practices. We use a framework common in economics and engineering fields alike, the Pareto frontier, to show the impact of four different best management practices on the tradeoffs between Se and cost objectives. We then extend that analysis to include institutional constraints that affect the economic feasibility associated with each practice. Results indicate that although water‐reducing strategies have the greatest impact on Se, they are the hardest for farmers to implement given constraints common to western water rights institutions. Therefore, our analysis shows that estimating economic and environmental tradeoffs, as is typically done with a Pareto frontier, will not provide an accurate picture of choices available to farmers where institutional constraints should also be considered.  相似文献   
9.
Horan, Richard D. and James S. Shortle, 2011. Economic and Ecological Rules for Water Quality Trading. Journal of the American Water Resources Association (JAWRA) 47(1):59‐69. DOI: 10.1111/j.1752‐1688.2010.00463.x Abstract: Emissions trading in textbook form uses markets to achieve pollution targets cost‐efficiently. This result is accomplished in markets that regulators can implement without knowing pollution abatement costs. The theoretical promise of emissions trading, along with real‐world success stories from air emissions trading, has led to initiatives to use trading for water pollution control. Yet, trading, particularly when it involves nonpoint sources of pollution, requires significant departures from the textbook concept. This paper explores how features of water quality problems affect the design of markets for water pollution control relative to textbook emissions markets. Three fundamental design tasks that regulators must address for pollution trading to achieve an environmental goal at low cost are examined: (1) defining the point and nonpoint commodities to be traded, (2) defining rules governing commodity exchange, and (3) setting caps on the commodity supplies so as to achieve an environmental target. We show that the way in which these tasks are optimally addressed for water quality markets differs significantly from the textbook model and its real‐world analogs. We also show that the fundamental appeal of emissions trading is lost in the case of realistic water quality markets, as market designs that reduce the costs of achieving water quality goals may no longer be implementable without the regulatory authority having information on abatement costs.  相似文献   
10.
为揭示中国经济持续增长对能源依靠程度、能源利用效率提高程度及环境污染改善水平,统计了2006年-2014年GDP、工业增加值、能耗、SO2和NOx排放量数据,计算得到单位能耗GDP和单位能耗污染物排放量,对比分析单位能耗GDP和单位能耗污染物排放量,前者持续增长,后者呈波动时下降,表明能源利用效率逐步提高,污染物排放得到有效控制.主要城市NOx和PM10浓度出现升高趋势,SO2浓度明显下降.NOx和PM10成为中国未来大气主要污染物,应采取措施控制,同时应注重对非工业源的控制.  相似文献   
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