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Mandatory insurance requirements and/or mitigation fees (royalties) for mining companies may help reduce environmental risk exposure for the federal government. Mining is examined since the Environmental Protection Agency (EPA) Toxic Release Inventory reveals that this sector produces more hazardous waste than any other industrial sector. Although uncommon, environmental expense can exceed hundreds of millions of dollars per development. Of particular concern is the potential for mines to become unfunded Superfund sites. Monte Carlo simulation of risk exposure is used to establish a plausible range of unfunded federal liabilities associated with cyanide-leach gold mining. A model is developed to assess these costs and their impact on both the federal budget and corporate profitability (i.e., industry sustainability), particularly if such costs are borne by offending firms.  相似文献   
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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   
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随着我国社会主义市场经济体制的建立和发展,企业将面临着一个日益完善的市场经济体系,这就要求企业的行为要更加规范。于是能够评价、分析企业盈利能力、生存能力、发展能力等各项指标的财务分析体系,就显得尤为重要了。本文主要从现行条件下财务分析体系入手,从财务分析体系的内容和发展前景两个方面,阐述了对财务分析体系发展的几点初步认识。  相似文献   
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基于2001-2010年CPI与15家旅游上市公司的财务数据,通过最小二乘回归模型和假设检验,分析了CPI变化对我国旅游上市公司盈利能力的影响,比较了CPI对景区类、酒店类、综合类旅游上市公司盈利能力影响的大小.结果发现,CPI对我国旅游上市公司盈利能力的影响是反向的和显著的;CPI对景区类、酒店类、综合类旅游上市公司盈利能力的影响存在差异;综合类高于景区类和酒店类,景区类高于酒店类.根据上述情况分析原因,提出相关建议.  相似文献   
5.
ABSTRACT: Changes in cropping patterns, water use, and profitability of producing sorghum with the LID (Limited Irrigation-Dryland) furrow irrigation system were compared with conventional irrigation practices. A recursive linear programming model was used to assess the economic impacts over a ten-year period. The analysis of various water resource situations in the High Plains of Texas indicated the LID system increased irrigated sorghum acreage over conventional practices. Although less irrigated and dryland wheat was generally produced, present value of returns increased from about $18 per acre to $50 per acre. Water use was slightly higher in most situations when using the LID system.  相似文献   
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Begging behaviour of nestling birds may involve more than a simple, honest source of information for parents to use in provisioning. Many aspects of begging behaviour relate instead to sibling competition for food items within the nest, and we might expect evidence of adaptive learning and behavioural adjustment in response to experience of the competitive environment. In this study, we consider begging in different locations within the nest as analogous to foraging in different patches, varying in food availability. Using hand-feeding trials, we created zones of differing profitability within an artificial nest by adjusting either the prey size or number of items delivered, and allowed only indirect competition between pairs of southern grey shrike (Lanius meridionalis) nestlings. Nestlings demonstrated the ability to detect differences in zone profitability and position themselves accordingly. By the end of both the prey size and delivery rate trials nestlings had increased the amount of time spent in the high quality zone. Such movement in response to differences in load quality, as well as frequency, demonstrates the ability of nestlings to learn about their environment and to facultatively adjust their begging in order to maximise energetic rewards.  相似文献   
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Wood charcoal production provides affordable energy in many developing countries and has substantially contributed to the economy through the provision of rural incomes. In several countries, charcoal production leads to overexploitation of forests due to inefficiencies in processing. This study was undertaken in central Laos to (1) examine and document traditional charcoal production systems; (2) investigate the production capacity, recovery efficiencies and economic gains of existing traditional charcoal production methods; (3) characterize the chemical properties of wood charcoal and investigate the potential for soil restoration and (4) investigate local charcoal producers' perception on forest degradation and their species preferences. Through a socio-economic survey, a cost-based method for economic valuation was undertaken on a range of charcoal production methods currently being used. Laboratory chemical analyses were performed on wood charcoal samples. Results indicated that the traditional mud charcoal mound was used by the majority (82%) of charcoal producers. Total charcoal production per production cycle varied between 400 (produced from 2.7 m3 of wood) and 1600 kg (produced from 18 m3 of wood), with a mean of 938 kg (±120) for traditional mud charcoal mounds. The volume of the traditional mud charcoal mounds correlated positively and significantly with total charcoal production (R 2 = 0.45, p?=?0.03), whereas correlated negatively and significantly with the recovery efficiency (R 2 = 0.58, p?=?0.01). On average, the local producers receive a total net benefit of 457,272 Lao kip (USD 57.2) in 17 days. We also identified a rice husk mound method of charcoal production, which may not encourage further deforestation while producing rice husk biochar that can be used for soil restoration. Furthermore, we found that there are significant differences (p < 0.05) between the sampled wood charcoals in chemical properties, indicating that the potential of using wood charcoal for the restoration of degraded soils varies from charcoal to charcoal.  相似文献   
8.
Since forager honeybees change their food-unloading behavior according to nectar-source profitability, an experiment was performed in order to analyze whether food-receivers modify their within-hive tasks related to different reward conditions. We offered individual foragers two reward conditions at a rate feeder while an additional feeder offered a constant reward and was of free access to the rest of the hive. Both feeders were the only food sources exploited by the colony during the assays since a flight chamber was used. After receiving nectar, hive bees performed processing cycles that involved several behaviors and concluded when they returned to the delivery area to receive a new food sample. During these cycles, receivers mainly performed oral contacts offering food, or inspected cells, and often both. In the latter case, both behaviors occurred simultaneously and at the same distance from the hive entrance. When they performed a single task, either the occurrence of cell inspections increased or contact offerings decreased for the highest reward rate offered to the donor-forager. Receivers also begged for food more often after interacting with low-profit foragers. Thus, the profitability of the food source exploited by nectar-forager honeybees could affect receiver behaviors within the hives based on individual-to-individual interactions.Communicated by R.F.A. Moritz  相似文献   
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大力发展风电产业有利于降低碳排放,对于保持经济社会可持续发展具有重要意义.跟其他的产业一样,产业组织结构是影响风电产业发展速度的决定因素之一.产业组织理论认为,产业的垂直结构影响着产业资源的配置效率、产业利润的分配和下游企业的定价.本研究回答两个问题:①风电制造企业市场集中度与风电场的利润率之间的关系;②它们之间的关系还受到哪些因素的影响.本文从中国风电产业链的垂直结构入手,分析了风电设备制造市场的市场集中程度对风电场利润的影响.理论模型的推导结果表明风电设备制造企业的市场集中度和风电场的利润率之间呈负相关关系,且影响程度随风电场对风电设备需求弹性的降低而加强.因此,本文认为政府可以通过给予风电设备制造企业税收优惠、在风电制造业中实施必要的反垄断措施和制定并实施中国风电产业标准等措施,吸引新的企业进入风电设备制造市场,降低设备制造市场的市场集中度,增加风电场对特定风电设备的需求弹性.从而提高风电场的利润,加快风电产业的健康发展.  相似文献   
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