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1.
Cascading costs:An economic nitrogen cycle   总被引:2,自引:0,他引:2  
The chemical nitrogen cycle is becoming better characterized in terms of fluxes and reservoirs on a variety of scales. Galloway has demonstrated that reactive nitrogen can cascade through multiple ecosystems causing environmental damage at each stage before being denitrified to N2. We propose to construct a parallel economic nitrogen cascade (ENC) in which economic impacts of nitrogen fluxes can be estimated by the costs associated with each stage of the chemical cascade. Using economic data for the benefits of damage avoided and costs of mitigation in the Chesapeake Bay basin, we have constructed an economic nitrogen cascade for the region. Since a single tonne of nitrogen can cascade through the system, the costs also cascade. Therefore evaluating the benefits of mitigating a tonne of reactive nitrogen released needs to consider the damage avoided in all of the ecosystems through which that tonne would cascade. The analysis reveals that it is most cost effective to remove a tonne of nitrogen coming from combustion since it has the greatest impact on human health and creates cascading damage through the atmospheric, terrestrial, aquatic and coastal ecosystems. We will discuss the implications of this analysis for determining the most cost effective policy option for achieving environmental quality goals.  相似文献   

2.
The chemical nitrogen cycle is becoming better characterized in terms of fluxes and reservoirs on a variety of scales. Galloway has demonstrated that reactive nitrogen can cascade through multiple ecosystems causing environmental damage at each stage before being denitrifled to N2. We propose to construct a parallel economic nitrogen cascade (ENC) in which economic impacts of nitrogen fluxes can be estimated by the costs associated with each stage of the chemical cascade. Using economic data for the benefits of damage avoided and costs of mitigation in the Chesapeake Bay basin, we have constructed an economic nitrogen cascade for the region. Since a single tonne of nitrogen can cascade through the system, the costs also cascade.Therefore evaluating the benefits of mitigating a tonne of reactive nitrogen released needs to consider the damage avoided in all of the ecosystems through which that tonne would cascade.The analysis reveals that it is most cost effective to remove a tonne of nitrogen coming from combustion since it has the greatest impact on human health and creates cascading damage through the atmospheric, terrestrial, aquatic and coastal ecosystems. We will discuss the implications of this analysis for determining the most cost effective policy option for achieving environmental quality goals.  相似文献   

3.
The chemical nitrogen cycle is becoming better characterized in terms of fluxes and reservoirs on a variety of scales. Galloway has demonstrated that reactive nitrogen can cascade through multiple ecosystems causing environmental damage at each stage before being denitrified to N2. We propose to construct a parallel economic nitrogen cascade (ENC) in which economic impacts of nitrogen fluxes can be estimated by the costs associated with each stage of the chemical cascade. Using economic data for the benefits of damage avoided and costs of mitigation in the Chesapeake Bay basin, we have constructed an economic nitrogen cascade for the region. Since a single tonne of nitrogen can cascade through the system, the costs also cascade. Therefore evaluating the benefits of mitigating a tonne of reactive nitrogen released needs to consider the damage avoided in all of the ecosystems through which that tonne would cascade. The analysis reveals that it is most cost effective to remove a tonne of nitrogen coming from combustion since it has the greatest impact on human health and creates cascading damage through the atmospheric, terrestrial, aquatic and coastal ecosystems. We will discuss the implications of this analysis for determining the most cost effective policy option for achieving environmental quality goals.  相似文献   

4.
High rates of crop residue removal as biofuel feedstocks could increase losses of nonpoint source pollutants, negatively affecting water quality. An alternative to residue removal can be growing dedicated bioenergy crops such as warm season grasses (WSGs) and short‐rotation woody crops (SRWCs). Yet, our understanding of the implications of growing dedicated bioenergy crops on water quality is limited. Thus, we (i) synthesized and compared the impacts of crop residue removal, WSGs, and SRWCs on water quality parameters (i.e., sediment and nutrient runoff, and nutrient leaching) and (ii) identified research gaps for growing dedicated energy crops. Literature indicates that residue removal at rates >50% (residue retention up to 4.71 Mg ha?1) can increase runoff by 5–15 mm, sediment loss by 0.2–7 Mg ha?1, NO3–N by 0.58–1 kg ha?1, and sediment‐associated C by 0.3–57 kg ha?1 per rainstorm event compared to no residue removal. Crop residue removal may also increase nutrient leaching. Studies on the impacts of growing WSGs as dedicated bioenergy crops at field scale on water quality parameters are few. However, WSGs when used as conservation buffers reduce losses of sediment by 66–97%, nutrients by 21–94%, and contaminants by 9–98%. This suggests that if WSGs were grown as dedicated bioenergy crops at larger scales, they could reduce losses of nonpoint source pollutants. Literature indicates that SRWCs can consistently reduce NO3–N leaching. More modeled than field data are available, warranting further field research on (i) field data collection from WSGs and SRWCs from marginal lands, (ii) growing monoculture or polyculture of WSGs, and (iii) large‐scale production of energy crops. Overall, dedicated bioenergy crops, particularly WSGs, can reduce losses of nonpoint source pollutants compared to residue removal and be an important strategy to improve water quality if grown at larger scales.  相似文献   

5.
The Neuse River Basin in North Carolina was regulated in 1998, requiring that all pollution sources (point and nonpoint) reduce nitrogen (N) loading into the Neuse Estuary by 30%. Point source N reductions have already been reduced by approximately 35%. The diffuse nature of nonpoint source pollution, and its spatial and temporal variability, makes it a more difficult problem to treat. Agriculture is believed to contribute over 50% of the total N load to the river. In order to reduce these N inputs, best management practices (BMPs) are necessary to control the delivery of N from agricultural activities to water resources and to prevent impacts to the physical and biological integrity of surface and ground water. To provide greater flexibility to the agricultural community beyond standard BMPs (nutrient management, riparian buffers, and water-control structures), an agricultural N accounting tool, called Nitrogen Loss Estimation Worksheet (NLEW), was developed to track N reductions due to BMP implementation. NLEW uses a modified N-balance equation that accounts for some N inputs as well as N reductions from nutrient management and other BMPs. It works at both the field- and county-level scales. The tool has been used by counties to determine different N reduction strategies to achieve the 30% targeted reduction.  相似文献   

6.
This article examines the use of economic analysis to inform bioinvasion management, with particular focus on forest resources. Economics is key for understanding invasion processes, impacts, and decision-making. Biological invasions are driven by and affect economic activities at multiple scales and stages of an invasion. Bioeconomic modeling seeks to inform how resources can be optimally allocated across invasion management activities—including prevention, surveillance programs for early detection and management, and controlling invasion populations and spread—to minimize the long-term costs and damages. Economic analysis facilitates understanding of decisions by public and private decision-makers, gaps between these, and the design of policies to achieve socially desirable outcomes. Private decision-makers may undercontrol invasions relative to socially optimal levels, because they generally account for their own costs and benefits of control but less often for broader ecosystem impacts or future spread across the landscape. Economic analysis considers approaches for increasing private invasion management and evaluates feedbacks between ecological and economic systems that can affect policy outcomes. Future research should continue evaluation and design of control strategies across the biosecurity continuum and across species to enhance cost-effectiveness, better incorporate uncertainty into policy design, increase focus on incentives and behavioral tools to influence private behaviors that affect invasion spread, and incorporate invasive species consideration within broader systems-focused science. In addition, challenges in valuing biodiversity and ecosystem service impacts and the costs and effectiveness of control measures are key data gaps. Greater collaboration between decision-makers and researchers will facilitate development and communication of usable economic research.  相似文献   

7.
Human alteration of the nitrogen (N) cycle has produced benefits for health and well-being, but excess N has altered many ecosystems and degraded air and water quality. US regulations mandate protection of the environment in terms that directly connect to ecosystem services. Here, we review the science quantifying effects of N on key ecosystem services, and compare the costs of N-related impacts or mitigation using the metric of cost per unit of N. Damage costs to the provision of clean air, reflected by impaired human respiratory health, are well characterized and fairly high (e.g. costs of ozone and particulate damages of $28 per kg NO(x)-N). Damage to services associated with productivity, biodiversity, recreation and clean water are less certain and although generally lower, these costs are quite variable (<$2.2-56 per kg N). In the current Chesapeake Bay restoration effort, for example, the collection of available damage costs clearly exceeds the projected abatement costs to reduce N loads to the Bay ($8-15 per kg N). Explicit consideration and accounting of effects on multiple ecosystem services provides decision-makers an integrated view of N sources, damages and abatement costs to address the significant challenges associated with reducing N pollution.  相似文献   

8.
The chemical nitrogen cycle is becoming better characterized in terms of fluxes and reservoirs on a variety of scales. Galloway has demonstrated that reactive nitrogen can cascade through multiple ecosystems causing environmental damage at each stage before being denitrified to N2. We propose to construct a parallel economic nitrogen cascade (ENC) in which economic impacts of nitrogen fluxes can be estimated by the costs associated with each stage of the chemical cascade. Using economic data for the benefits of damage avoided and costs of mitigation in the Chesapeake Bay basin, we have constructed an economic nitrogen cascade for the region. Since a single ton of nitrogen can cascade through the system, the costs also cas  相似文献   

9.
Nutrient pollution, now the leading cause of water quality impairment in the U.S., has had significant impact on the nation"s waterways. Excessive nutrient pollution has been linked to habitat loss, fish kills, blooms of toxic algae, and hypoxia (oxygen-depleted water). The hypoxic "dead zone" in the Gulf of Mexico is one of the most striking illustrations of what can happen when too many nutrients from inland watersheds reach coastal areas. Despite programs to improve municipal wastewater treatment facilities, more stringent industrial wastewater requirements, and agricultural programs designed to reduce sediment loads in waterways, water quality and nutrient pollution continues to be a problem, and in many cases has worsened. We undertook a policy analysis to assess how the agricultural community could better reduce its contribution to the dead zone and also to evaluate the synergistic impacts of these policies on other environmental concerns such as climate change. Using a sectorial model of U.S. agriculture, we compared policies including untargeted conservation subsidies, nutrient trading, Conservation Reserve Program extension, agricultural sales of carbon and greenhouse gas credits, and fertilizer reduction. This economic and environmental analysis is watershed-based, primarily focusing on nitrogen in the Mississippi River basin, which allowed us to assess the distribution of nitrogen reduction in streams, environmental co-benefits, and impact on agricultural cash flows within the Mississippi River basin from various options. The model incorporates a number of environmental factors, making it possible to get a more a complete picture of the costs and co-benefits of nutrient reduction. These elements also help to identify the policy options that minimize the costs to farmers and maximize benefits to society.  相似文献   

10.
Worldwide, we rely on introduced plants for the essentials of human life; however, intentional plant introductions for commercial benefit have resulted in invaders with negative environmental, economic or social impacts. We argue that plant species of low expected economic value should be less acceptable for introduction than species of high economic value if their other traits are similar; however, key traits such as likelihood of escape and costs of escape are often highly uncertain. Methods do not currently exist which allow decision makers to evaluate costs and benefits of introduction under uncertainty. We developed a cost-benefit analysis for determining plant introduction that incorporates probability of escape, expected economic costs after escape, expected commercial benefits, and the efficiency and cost of containment. We used a model to obtain optimal decisions for the introduction and containment of commercial plants while maximizing net benefit or avoiding losses. We also obtained conditions for robust decisions which take into account severe uncertainty in model parameters using information-gap decision theory. Optimal decisions for introduction and containment of commercial plants depended, not only on the probability of escape and subsequent costs incurred, but also on the anticipated commercial benefit, and the cost and efficiency of containment. When our objective is to maximize net benefit, increasing uncertainty in parameter values increased the likelihood of introduction; in contrast, if our objective is to avoid losses, more uncertainty decreased the likelihood of introduction.  相似文献   

11.
To improve the sustainability of agricultural systems of the Lombardia region (northern Italy), a mixed indicator-model-expert approach was used. Starting from the results of a previous assessment of current management (ACT) in dairy and arable farms, alternative management scenarios at field level were designed in order to reduce nitrogen (N) losses whilst maintaining or improving the environmental and economic sustainability at the farming system level. By working with a group of experts supported by a mechanisation model and a cropping system model, two alternative N management scenarios were defined following a step-by-step decision procedure. The first scenario (FERT) is an improvement of the current fertiliser management scheme, applied at the same crops as in ACT and aimed at maintaining the same yields. The second scenario (ROT) is based on changes in crop rotations by introducing new crops to reduce N losses and to maintain economic profitability. The sustainability of the two scenarios was assessed and compared with agro-ecological and economic indicators. The results of FERT, indicate that the application of adequate N management plans tuned to the production target and the promotion of best management practices may help to reduce N surplus and consequently to save fossil energy and to decrease the costs of production. In the ROT scenario, the introduction of alfalfa cultivation reduces N surplus on maize, whereas intensive double cropping systems (two crops harvested in 12 months) increase N surplus and require higher energy consumptions and production costs compared to cultivating a summer crop only. However, in rotational systems more favourable weed population dynamics are expected compared to ACT. Both alternative scenarios were not implemented in practice, but they are realistic and are consistent with results of experiments where management options similar to those introduced in FERT and ROT were tested.This work indicates that the rational integration between scientific tools (indicators and models) and expert knowledge is adequate to deal with complex farming and cropping systems, which require a multidisciplinary approach.  相似文献   

12.
For implementation of specific actions to reduce risks, there is lack of a unified tool to compare different mitigation investment strategies and to prioritize alternative mitigation measures. Organizations usually address some operational risks such as business interruption (BI) losses. Computable general equilibrium (CGE) models are state-of-the-art economic tools to account for BI losses. This study proposed a new, improved dynamic CGE model to analyze and compare mitigation investment measures that aim at reducing BI losses. The new model, a time-recursive dynamic model reflecting the recovery and reconstruction period, connects reconstruction investment with reconstruction funds source, such as from government, household, enterprise, or outside a disaster-affected area. The 2008 Wenchuan earthquake in China was selected as a case study to illustrate the new model. Some interesting topics about mitigation investment were analyzed: (1) the relative importance of pre-disaster reduction investment versus post-disaster reconstruction investment; (2) post-disaster economic recovery with the contribution of insurance compensation; (3) the optimal ratio between mitigation funds collected from the disaster-affected area and that collected from outside the disaster-affected area; (4) the rational division of limited mitigation funds to each year during the restoration and reconstruction period.  相似文献   

13.
N2O emissions from the biological treatment of sewage, manure, landfill leachates and industrial effluents have gained considerable interest among policy makers and environmental scientists. Estimated global emission rates from these sources can contribute up to 10% of the anthropogenic N2O emissions. Particularly at the level of a treatment plant, the N2O impact can be very significant and reach up to 80% of the operational CO2 footprint. Imperfect nitritation by an imbalance in the two-step nitritation metabolism of ammonia-oxidizing bacteria is considered as the main contributor to N2O production with hydroxylamine and particularly nitrite as key precursors. Monitoring of these compounds is warranted to understand and abate N2O emissions. Mitigation strategies should also comprise optimizations of the process parameters as well as bio-augmentative approaches empowered to restore the functional capacity and to deal with unwanted accumulation of intermediates. These strategies require validation for their effectiveness and costs at full-scale.  相似文献   

14.
Nitrogen (N) losses from livestock houses and manure storage facilities contribute greatly to the total loss of N from livestock farms. Volatilisation of ammonia (NH3) is the major process responsible for the loss of N in husbandry systems with slurry (where average dry matter content varies between 3 and 13%). Concerning this volatilisation of NH3, the process parameters of pH and air temperature are crucial. During a period of approximately 10 years, systematic measurements of NH3 losses originating from a large variety of different livestock houses were made. One of the problems with NH3 emissions is the large variation in the measured data due to the season, the production of the animals, the manure treatment, type of livestock house, and the manure storage. Generally speaking, prevention and control of NH3 emission can be done by control of N content in the manure, moisture content, pH, and temperature. In houses for growing pigs, a combination of simple housing measures can be taken to greatly reduce NH3 emissions. In houses for laying hens, the control of the manure drying process determines the emission of NH3. Monteny has built an NH3 production model with separate modules for the emission of the manure storage under the dairy house and the floor in the house. Manure spreading is also a major source of NH3 emission and is dependent on slurry composition, environmental conditions, and farm management. The effects of these factors have been employed in a model. Losses via NO, N2O, and N2 are important in husbandry systems with solid manure and straw. The number of experimental data is, however, very limited. As N2O is an intermediate product of complex biochemical processes of nitrification and denitrification, optimal conditions are the key issues in N2O reduction strategies. We may expect that in the near future the emission of greenhouse gases will get the same attention from policy makers as NH3. Sustainable livestock production has to combine low emissions of gaseous N compounds with acceptable odour emissions, low emissions of greenhouse gases, and acceptable standards of animal welfare. For the entrepreneur, the strategy must be built on the regulations, the special conditions of his farm, and what is reasonably achievable.  相似文献   

15.
The agriculture sector has historically been a major source of greenhouse gas (GHG) emissions into the atmosphere. Although the use of synthetic fertilizers is one of the most common widespread agricultural practices, over-fertilization can lead to negative economic and environmental consequences, such as high production costs, depletion of energy resources, and increased GHG emissions. Here, we provide an analysis to understand the evolution of cereal production and consumption of nitrogen (N) fertilizers in Brazil and to correlate N use efficiency (NUE) with economic and environmental losses as N2O emissions. Our results show that the increased consumption of N fertilizers is associated with a large decrease in NUE in recent years. The CO2 eq. of N2O emissions originating from N fertilization for cereal production were approximately 12 times higher in 2011 than in 1970, indicating that the inefficient use of N fertilizers is directly related to environmental losses. The projected N fertilizer forecasts are 2.09 and 2.37 million ton for 2015 and 2023, respectively. An increase of 0.02% per year in the projected NUE was predicted for the same time period. However, decreases in the projected CO2 eq. emissions for future years were not predicted. In a hypothetical scenario, a 2.39% increase in cereal NUE would lead to $ 21 million savings in N fertilizer costs. Thus, increases in NUE rates would lead not only to agronomic and environmental benefits but also to economic improvement.  相似文献   

16.
Abstract The hypothesis that economic damage due to nonpoint pollution exceeds costs of mitigation can be tested by ecologists, economists, and resource managers working at the spatial scale of watersheds for periods of years to decades. We present a framework for combining ecological and economic information to compare management scenarios for nonpoint pollution. Eutrophication of lakes caused by nonpoint phosphorus pollution, a common environmental problem, is the focus of our approach. Economic advantages of mitigating nonpoint pollution increase as the uncertainty of ecological predictions decreases. Uncertainty is measured by the prediction variance of nonpoint pollution models. A major source of variance in nonpoint pollution predictions is the effect of land use change on phosphorus transport. This variance is often large because calibration data sets do not have sufficiently wide ranges of land use variables. Ecological predictions and the resulting economic assessments could be improved by comparative studies of watersheds with contrasting land uses, and by viewing nonpoint pollution management as a large-scale experiment.  相似文献   

17.
Battelli G 《Parassitologia》2004,46(4):359-362
The socio-economic impact of cystic echinococcosis (CE), caused by Echinococcus granulosus, is reviewed with special reference to the following topics: consequences in man and livestock, costs and benefits of control programmes and economic procedures for evaluating control programmes. Examples of some important costs and benefits are given. Many consequences in man and livestock are difficult to evaluate from an economic point of view, because some basic data are difficult to obtain in many countries. However, the socio-economic evaluation of the consequences of CE and of the present and future control actions proves indispensable to best use available resources and possibly tailor control stategies.  相似文献   

18.
Inequalities in health in the United Kingdom are widening as a result of economic policy. By focusing on specific diseases, health policy fails to address why less prosperous groups die earlier from most major categories of death. By concentrating on actions which can be taken by individuals and local communities health policy ignores actions which require the support and involvement of society as a whole. Clinicians see the consequences of health and economic policy in their everyday practice and could contribute more effectively to public debate.  相似文献   

19.
In recent years, policy makers in high-income countries have placed an increasing emphasis on the value of maintaining good mental health, recognizing the contribution that this makes to quality of life, whilst ever more mindful of the socio-economic consequences of poor mental health. The picture in many other parts of the world is much less encouraging; policy attention and resources are still directed largely at communicable diseases. We reflect on some of the challenges faced in these countries and outline the role that economic evidence could play in strengthening the policy case for investment in mental health. Clearly this should include assessment of the economic impact of strategies implemented outside, as well as within the health sector. The ways in which mental health services are delivered is also of critical importance. Non-governmental organizations (NGOs) have long been shown to be key stakeholders in the funding, coordination and delivery of these services in high-income countries. Their role in low- and middle-income countries, where infrastructure and policy focus on mental health are more limited, can be even more vital in overcoming some of the barriers to the development of mental health policy and practice.  相似文献   

20.
生物入侵的危害与防治对策   总被引:30,自引:8,他引:22  
生物入侵是一个世界范围的生态学现象。入侵种通过竞争、捕食、改变生境和传播疾病等方式对本地种及其系统产生影响。生物入侵的危害表现为:造成巨大的经济损失,仅美国每年因外来种入侵造成的经济损失近1370亿美元;威胁到人类的健康和生存。成千上万的人被外来种传染疾病以致死亡;引起严重的社会恐慌和动荡,人们寝食不安;改变了生态系统的结构和功能,全球自然灾害频频爆发;导致生物多样性的急剧下降,威胁到子孙后代的生存和发展。防治生物入侵有3条途径:实行全面检疫,阻止外来种的偶然入侵;采取全面的生态评估和监测,防范引进品种的入侵灾难;对已入侵的外来种采用机械法、化学法和生物防治法进行根除和控制,应用生物防治法、筛选天敌和对其进行危害评估时要特别慎重。  相似文献   

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