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1.
我国上市公司资本结构的主要特点是偏好股权投资、流动负债比率偏高、债券比重小。要改变我国上市公司资本结构中呈现的重股轻债的状况,需采取优化股权结构、发展和完善债券市场、规范股市行为等措施,使我国上市公司的资本结构日趋合理。  相似文献   

2.
A detailed inventory shows that an average resident of the City of New Haven depends on a per capita capital stock of 9200 kg/c of iron and 144 kg/c of copper in the city infrastructure, buildings, transportation systems, and equipment. Of the iron stock 28% is in items such as rail cars and ships in ocean trade not permanently within the city, and 22% is devoted to receiving and delivering oil fuel to the city and its surrounding communities. Copper is principally used in the distribution of electric power and in water piping within buildings. The city's 9200 kg/c of iron stock-in-use is less than the 13,000 kg/c national average due to New Haven's lack of heavy industry and relatively small number of large buildings. The 144 kg/c of copper stock-in-use is only 58% of the overall value for the United States, but is comparable to that in cities such as Stockholm, Sweden. Attainment of a level of iron and copper services with contemporary technology in less developed countries to the level enjoyed in New Haven would require consumption of the presently identified world copper resources.  相似文献   

3.
We intend to estimate the value of ecosystem services in the U.S. State of New Jersey using spatially explicit benefit transfer. The aggregated net rent, a conservative underestimate for the total economic value of the state’s natural environment, ranged from 11.6 to11.6 to 19.6 billion/year, conditional on how inclusive we were in selecting the primary studies used to calculate the central tendency values to transfer. In addition to calculating the range, mean, and standard deviation for each of 12 ecosystem services for 11 Land Use/Land Cover (LULC) types, we also conduct a gap analysis of how well ecosystem service values are represented in the literature. We then map these values by assuming a mean value for each LULC and apply this to spatial data. As to sensitivity analysis, we calculate the net present value of New Jersey’s natural environment utilizing three different methods of discounting. These research results provide a useful, albeit imperfect, basis for assessing the value of ecosystem services and natural capital, and their comparison with the value of conventional human and built capitals.  相似文献   

4.
Co‐management involves the shared administration of natural resources by two or more parties. This study examines the role of social capital in the process of developing co‐management in three river corridors in Canada. Qualitative analysis reveals that social capital acts as a catalyst helping groups to progress through the stages of the co‐management process. Forms of social capital (bridging and bonding) are identified that advance and/or inhibit the development of co‐management. The article reaffirms the need to expand the institutional basis for natural resource management and provides empirical evidence that social capital plays a fundamental role in developing co‐management. In conclusion, the article suggests that resource agencies need to recognize the value of social capital and the necessity for government representatives to be informed of and practiced in these skills, if they are to engage meaningfully with the civilian population.  相似文献   

5.
当前学术界对于GEP的概念内涵和核算方法仍在探索之中,而地方实践已然走在理论研究之前。GEP核算是生态服务价值的货币化评价,主要是为了科学认识生态系统服务的潜在价值,不等同于生态服务价值的市场显现;核算的出发点是为了更好保护自然资本,而非生态产品价值转化。GEP核算通过货币化评价生态服务价值,将自然资本保护更好地纳入经济社会发展决策,为完善生态补偿机制、进行生态文明绩效考核、引导人造资本和人力资本进入生态产业化提供重要参考依据。GEP和GDP都是流量,将GEP直接转化为GDP在逻辑上不成立。如何使GEP核算更好地服务于生态产品价值实现,需要在理论上厘清逻辑关联,在实践中明晰政策边界。  相似文献   

6.
Valuation of Ecological Resources and Functions   总被引:8,自引:0,他引:8  
/ Ecological resources are natural resources that provide certain necessary but overlooked system maintenance functions within ecosystems. Environmental economics is in search of an appropriate analysis framework to determine economic values of such resources. This paper presents a framework that estimates and compiles the components of value for a natural ecosystem. The framework begins with the ecological processes involved, which provide functions within the ecosystem and services valued by humans. We discuss the additive or competive nature of these values, and estimate these values through conventional and unconventional techniques. We apply the framework to ecological resources in a shrub-steppe dryland habitat being displaced by development. We first determine which functions and services are mutually exclusive (e.g., farming vs soil stabilization) and which are complementary or products of joint production (e.g., soil stabilization and maintenance of species). We then apply benefit transfer principles with contingent valuation methodology (CVM), travel cost methodology (TCM), and hedonic damage pricing (HDP). Finally, we derive upper-limit values for more difficult-to-value functions through the use of human analogs, which we argue are the most appropriate method of valuation under some circumstances. The highest values of natural shrub-steppe habitat appear to be derived from soil stabilization.KEY WORDS: Natural resource economics; Ecological economics; Ecological resources; Shrub-steppe; Environmental valuation; Cost; Benefit; Value  相似文献   

7.
基于成本分析的西部生态补偿法律机制研究   总被引:1,自引:0,他引:1  
建立和实施西部生态补偿机制,是加强西部生态建设和强化西部生态功能专业化服务的必由之路。生态系统服务补偿理论和自然资本理论为我们分析西部生态补偿提供了新的分析范式,西部生态补偿包括国家补偿、区域和流域补偿、自力补偿三个层次。其内部的成本关系包括生态服务利用成本关系、跨区域资源调配成本关系、生态工程实施成本关系、内部补偿成本关系等,基于成本分析基础上的三层次补偿关系协同发展是完善西部生态补偿法律机制的基本内容。  相似文献   

8.
Valuing goods and services from open oceans provides arguments for the ocean's protection and plays an increasingly important role in debates on the use and management of natural resources. This paper identifies and estimates the monetary value of some of the most important goods and services provided by open oceans. The list of goods and services considered includes food production, raw materials, water supply, CO2 regulation, bioremediation of waste, biomass and biodiversity conservation. Therefore, not only values associated with productive uses are quantified but also values assigned to other biological ecosystem services. This paper constitutes a first attempt in the open ocean literature at evaluating services such as water supply, biomass and biodiversity conservation. To obtain their monetary value, different techniques, some not applied before in this area, have been used depending on the ecosystem service to be evaluated. As a general criterion we use the concept of net value added (revenues obtained from the services less incurred costs). Our methodology is illustrated by estimating the monetary values of goods and services provided by the open ocean ecosystem of Spain as defined by its exclusive economic zone. The total economic value obtained measures the contribution of oceans to overall welfare and it may be an important instrument in managing open ocean ecosystems and developing environmental policies in the future.  相似文献   

9.
A new environmental paradigm has emerged, reflecting a change in the public's understanding of resource sustainability. Forest policy makers need to be better informed about such changes to achieve economic, social, and environmental objectives in a manner that balances human needs and aspirations with ecosystem constraints. As an aid to this task, a forest resource accounting system based on the key concept of natural capital could help reshape forest policies to provide an even wider spectrum of benefits for both present and future generations by maintaining and enhancing the productive capacity of forest capital. Such a resource accounting system would provide a tool for integrating multidimensional information requirements in measuring the health of both forest ecosystems and economic systems. This paper outlines some of the features of this accounting system and proposes and framework that would integrate economic and ecological characteristics of natural resources. Forest resource accounting is urgently needed to achieve the sustainability goals of ecosystem management.  相似文献   

10.
Research on ecosystem services has focused mostly on natural areas or remote places, with less attention given to urban ecosystem services and their relationship with technological change. However, recent work by urban ecologists and urban designers has more closely examined and appreciated the opportunities associated with integrating natural and built infrastructures. Nevertheless, a perception remains in the literature on ecosystem services that technology may easily and irreversibly substitute for services previously obtained from ecosystems, especially when the superiority of the engineered system motivated replacement in the first place. We emphasize that the expected tradeoff between natural and manufactured capital is false. Rather, as argued in other contexts, the adoption of new technologies is complementary to ecosystem management. The complementarity of ecosystem services and technology is illustrated with a case study in Barcelona, Spain where the installation of sophisticated water treatment technology increased the value of the ecosystem services found there. Interestingly, the complementarity between natural and built infrastructures may remain even for the very ecosystems that are affected by the technological change. This finding suggests that we can expect the value of ecosystem services to co-evolve with new technologies. Technological innovation can generate new opportunities to harness value from ecosystems, and the engineered structures found in cities may generate more reliance on ecosystem processes, not less.  相似文献   

11.
The purpose of this short article is to set static and dynamic models for optimal floodplain management and to compare policy implications from the models. River floodplains are important multiple resources in that they provide various ecosystem services. It is fundamentally significant to consider environmental externalities that accrue from ecosystem services of natural floodplains. There is an interesting gap between static and dynamic models about policy implications for floodplain management, although they are based on the same assumptions. Essentially, we can derive the same optimal conditions, which imply that the marginal benefits must equal the sum of the marginal costs and the social external costs related to ecosystem services. Thus, we have to internalise the external costs by market-based policies. In this respect, market-based policies seem to be effective in a static model. However, they are not sufficient in the context of a dynamic model because the optimal steady state turns out to be unstable. Based on a dynamic model, we need more coercive regulation policies.  相似文献   

12.
The Great Lakes watershed is home to over 40 million people (Canadian and U.S.) who depend on a healthy Great Lakes ecosystem for economic, societal, and personal vitality. The challenge to policymakers and the public is to balance economic benefits with the need to conserve and replenish regional natural resources in a manner that ensures long term prosperity. Nine critical broad-spectrum stressors of ecological services are identified, which include pollution and contamination, agricultural erosion, non-native species, degraded recreational resources, loss of wetlands habitat, climate change, risk of clean water shortage, vanishing sand dunes, and population overcrowding. Many of these stressors overlap. For example, mining activities alone can create stress in at least five of these categories. The focus groups were conducted to examine the public’s awareness of, concern with, and willingness to expend resources on these stressors. This helped generate a grouping of stressors that the public is especially concerned about, those they care little about, and everything else in between. Stressors that the respondents have direct contact with tend to be the most important to them. This approach of using focus groups is a critical first step in helping natural resource managers such as Trustees and NGOs understand what subsequent steps to take and develop policy measures that are of most interest and value to the public. Skipping or glossing over this key first task could lead to difficulties with respect to survey design and model development in a non-market valuation study. The focus group results show that concern related to pollution and contamination is much higher than for any of the others. It is thus clear that outreach programs may be necessary to educate the public about the severity of some low-ranked stressors including climate change.  相似文献   

13.
A significant amount of mineral aggregates are used in constructing, rehabilitating and maintaining roads. As local (nearby) quarries get exhausted, aggregates need to be hauled from sources that are at ever-greater distances. Hence, over time the cost of trucking as well as the amount of emissions generated by trucking increases with a decrease of local natural aggregate stocks. The objectives of this study are to construct and utilize a system dynamics model of the depletion of a stock of natural aggregates due to pavement construction and maintenance, and determine the effect of using local and nonlocal aggregates, recycling and project cancellation (slowing growth) on the paving of roads. Long-term simulations are carried out with available aggregate stock, trucking distance and cost data. The quality of roads and a sustainability score, based on engineering, economic and environmental factors (emissions) are evaluated for different scenarios. An optimal combination of the use of local and nonlocal recycled aggregates, recycling and project cancellation is recommended. The proposed system dynamics model could be utilized by agencies to plan for the proper utilization of aggregate resources for road development and maintenance/rehabilitation projects.  相似文献   

14.
Natural landscapes produce goods and services, such as fish, wildlife, recreation, climate control, that are not adequately incorporated in their market values. Contingent Valuation (CV) and Energy Analysis (EA) approaches were used to estimate the nonmarket value of forests in Georgia. Both methods yielded similar estimates of approximately $200 ha–1, which was 31% of the total market and nonmarket value of forests. Energy analysis was also used to estimate the nonmarket value of the major land uses in Georgia. Relative contributions of nonmarket value to total value ranged from 0.1% for urban areas to approximately 100% for wetlands. For the state as a whole, nonmarket production of natural and developed ecosystems was estimated at $2.6 billion. This value is comparable to annual marketed agricultural ($2.8 billion) and timber ($4.5 billion) production, both very important industries in Georgia. Changing land use patterns in Georgia and elsewhere are likely to be accompanied by shifts in the relative importances of market and non-market values.  相似文献   

15.
The concept of natural behavior is a key element in current Dutch policy-making on animal welfare. It emphasizes that animals need positive experiences, in addition to minimized suffering. This paper interprets the concept of natural behavior in the context of the scientific framework for welfare assessment. Natural behavior may be defined as behavior that animals have a tendency to exhibit under natural conditions, because these behaviors are pleasurable and promote biological functioning. Animal welfare is the quality of life as perceived by the animal. Animals have evolved cognitive-emotional systems (“welfare needs”) to deal with a variable environment. Animals do not only have so-called physiological needs such as the need for food, water, and thermal comfort. They also need to exercise certain natural behaviors such as rooting or nest-building in pigs, and scratching or dust-bathing in poultry. All needs must be taken into account in order to assess overall welfare. The degree of need satisfaction and frustration can be assessed from scientific information about the intensity, duration, and incidence of (welfare) performance criteria such as measurements of behavior and/or (patho)physiology. Positive welfare value relates to how animals are inclined to behave under natural conditions, in preference tests, and in consumer-demand studies. Negative welfare value relates to stress, frustration, abnormal behavior, aggression, and reduced fitness. Examples are given to illustrate how the need to perform natural behaviors can be assessed following the general principles for welfare assessment, providing a first approximation of how different natural behaviors affect animal welfare.  相似文献   

16.
This research studies the relationship between the capital structure of a firm and its asset utilization rate in resource intensive industries. We study this issue from both private and public policy perspectives. From a private perspective, it's conceivable that a positive relationship may exist because a company is trying to increase its use of debt to effect a more efficient utilization of its assets. However, from a public policy perspective, finding a positive relationship between asset utilization and debt levels in natural resource sensitive industries may signal a sub-optimal exploitation of natural resources when debt levels rise. This research examines measures of leverage and asset utilization in firms from the mining, oil, and timber industries to determine whether the behavior alleged in the PALCO/MAXXAM case (an increased cutting rate to pay off junk bond financing) has been observed more systematically. We observe a positive relationship between leverage and asset utilization in all three industries when leverage is calculated using book value measures. When market value measures are used, this positive relationship no longer holds in the mining industry. Possible explanations for these results are offered.  相似文献   

17.
我国鲟鱼类资源及其保护与发展途径   总被引:1,自引:0,他引:1  
鲟鱼类为北半球古老的大型经济鱼类,栖息于太平洋、大西洋和内陆水域,是世界著名的经济鱼类.近年来在有关科研项目的支持下,对我国境内的11种鲟鱼类资源进行了生物学、生态学等方面的一系列调查研究.本文着重论述了鲟鱼类的自然分布、经济与科研价值,分析了资源现状及其衰退原因,并提出今后资源保护与发展的8个途径.  相似文献   

18.
Choice modelling is an emerging approach to estimating the non-use values of environmental services with multiple attributes. In this paper, results are reported of a choice modelling study conducted in the Herbert River District of North Queensland to estimate the value placed on the protection of natural vegetation in areas suitable for cane production by the local community. Resource use options that vary in the level of environmental protection and the level of agricultural production were presented as a series of choice sets and respondents were asked to choose among a set of three discrete alternatives in a given choice set. The alternatives in each choice set were described by four attributes, pertaining to the area of teatree woodlands, the area of vegetation along rivers and in wetlands, regional income from cane production, and an environmental levy. The responses were analysed together with socio-economic data using a nested-logit discrete-choice model to estimate the community willingness-to-pay for the protection of natural vegetation. The results indicate that the environmental values of wetlands are comparable to returns from commercial production of sugar cane and that the values of teatree woodlands are comparable to returns from extensive grazing. It is argued that land allocation policies should recognise these values in tandem with commercial benefits of production to ensure that resources are used more efficiently.  相似文献   

19.
As demand for water in the southwestern United States increases and climate change potentially decreases the natural flows in the Colorado River system, there will be increased need to optimize the water supply. Lake Powell is a large reservoir with potentially high loss rates to bank storage and evaporation. Bank storage is estimated as a residual in the reservoir water balance. Estimates of local inflow contribute uncertainty to estimates of bank storage. Regression analyses of local inflow with gaged tributaries have improved the estimate of local inflow. Using a stochastic estimate of local inflow based on the standard error of the regression estimator and of gross evaporation based on observed variability at Lake Mead, a reservoir water balance was used to estimate that more than 14.8 billion cubic meters (Gm3) has been stored in the banks, with a 90% probability that the value is actually between 11.8 and 18.5 Gm3. Groundwater models developed by others, observed groundwater levels, and simple transmissivity calculations confirm these bank storage estimates. Assuming a constant bank storage fraction for simulations of the future may cause managers to underestimate the actual losses from the reservoir. Updated management regimes which account more accurately for bank storage and evaporation could save water that will otherwise be lost to the banks or evaporation.  相似文献   

20.
The La Antigua watershed drains into the Gulf of Mexico and can be considered as one of the most important areas in Mexico because of its high productivity, history, and biodiversity, although poverty remains high in the area in spite of these positive attributes. In this study, we performed an integrated assessment of the watershed to recommend a better direction toward a sustainable management in which the four capitals (natural, human, social, and built) are balanced. We contrasted these four capitals in the municipalities of the upper, middle and lower watershed and found that natural capital (natural ecosystems and ecosystem services) was higher in the upper and middle watershed, while human and social capitals (literacy, health, education and income) were generally higher downstream. Overall, Human Development Index was negatively correlated with the percentage of natural ecosystems in the watershed, especially in the upper and lower watershed regions. Our results indicate that natural capital must be fully considered in projections for increasing human development, so that natural resources can be preserved and managed adequately while sustaining intergenerational well-being.  相似文献   

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