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11.
王伟  孙平军  杨青山 《地理科学》2018,38(4):539-547
基于传统各学科分析的城市群形成与演进的影响因子,依据因子作用的方式和属性分成3类、阐释三者之间相互联系和作用的机理,在此基础上构建纳入制度因子的城市群形成与演进的影响因子综合分析模型;基于新制度经济学视角阐释制度视角的城市群形成与演进的作用机理,提出其实质就是现有制度及其变迁过程中是如何影响人的行为选择,人的行为又如何影响城市群形成与演进过程中的各项经济活动(实体因子),进而明晰制度及其演变对城市群形成与演进中的作用机理,并据此从宏观制度变迁视角、中观机制设计视角、微观交易成本视角构建了城市群形成与演进机理的新制度经济学解释框架和具体主要研究内容的设计。  相似文献   
12.
In this paper, the authors analyze a wide range of recreational management strategies for their impacts on red snapper yield, economic surplus and the fish stock. Simulating a wide range of policies, the authors find Data Envelopment Analysis (DEA) inspired policy efficiency frontiers that lead to finding those management strategies that offer the greatest level of economic surplus for any biological target, looking at both the east and west Gulf of Mexico fisheries. Red snapper has been declared overfished since 1988 and the 2005 SEDAR 7 stock assessment declared red snapper were overfished and undergoing overfishing. In November 2009, the update of the assessment declared that overfishing was no longer occurring but that the red snapper stocks needed to be rebuilt. In this analysis, it was found that red snapper are neither overfished or undergoing overfishing. The main difference between the present model and the SEDAR 7 model is that the latest model uses a higher mortality rate for juveniles and a density dependent model. The authors also suggest that the east and west should be managed as separate units.  相似文献   
13.
Regulatory agencies in the United States do not generally consider economic values of ecosystem services in their policy decisions. We report the results of a collaborative effort by a team of economists, conservation biologists, and staff members of the California Ocean Protection Council to provide spatially explicit and policy-relevant values for ecosystem services generated in coastal regions in California. We developed a matrix in which the rows are types of ecosystem services and the columns are types of marine ecosystems along the California coast. Where possible, we populated this matrix with ecosystem service values per unit of area drawn from the economics literature. We then evaluated whether the values for given services, in given ecosystems, could be reasonably approximated by applying the replacement cost or the avoided cost method. Reported values of coastal ecosystems varied widely, and much of the valuation research did not address specific ecosystem services. Even when ecosystem services were explicitly addressed, the services often were not described or valued in a spatially explicit manner. These results suggest that rigorous application of non-market values to policy decisions requires original valuation studies for specific services in specific ecosystems. Where original, place-based valuation studies are not possible, valuation by replacement or avoided cost methods is feasible for some ecosystem services.  相似文献   
14.
公众对气象信息需求的规律与公共气象服务   总被引:2,自引:0,他引:2  
韩佳芮  叶谦  田青 《干旱气象》2007,25(2):82-89
通过对“北京2008奥运气象服务社会需求调查”所得资料的统计定量分析,揭示出公众对气象信息的需求呈现出以下规律:公众最为关注的气象信息、指数(夏季温度、污染相关信息)受生理需求驱动;次关注的信息(高影响天气和人体舒适相关信息)与公众的安全感和追求高品质生活有关;而关注程度相对较低的信息具有2个特点:(1)需求人群相对特殊;(2)难以从大部分媒体获得。分析表明,所发现的公众气象信息需求规律基本符合马斯洛需求层次理论。而行为经济学信息易得性理论对调查中所发现的冰雹和降水概率的低关注度问题则有较好的解释。本研究所得结果为气象部门改进气象信息服务工作有一定的启示。  相似文献   
15.
1INTRODUCTIONTheaceleratedreleaseofsedimentfromsoilandrocksurfacesanditsmovementto,through,andfromstreamsisthemostpervasivean...  相似文献   
16.
An Irish commercial fishery for orange roughy began in the Northeast Atlantic in 2001 with the assistance of government grants. The fishery began as an open access, non-quota fishery. The rapid boom and bust of many deep water fisheries was experienced. Landings peaked in 2002 and then dropped significantly the following year. Many vessels were forced out of the fishery due to high costs and rapidly declining stocks. By 2005 the fishery was largely closed. Applying a bioeconomic analysis, this paper shows why the fishery no longer exists and discusses both the external and opportunity costs of the fishery. A bioeconomic model is applied to the available data to assess the open access effort and harvest with and without government grant aid. The results suggest that in the absence of subsidies, deep water trawling would not have been viable. In addition to the financial costs such as high fuel consumption, there are also externalities associated with deep water trawling. Orange roughy is closely associated with deep water ecosystems such as seamounts and cold water corals. This paper examines the costs of damage to cold water corals. These costs include the loss of fish habitats and lost future use and preservation values.  相似文献   
17.
During the last decade a number of Large Marine Protected Areas (LMPAs) – marine protected areas that exceed a minimum size threshold and are often in offshore or open ocean waters – have been designated in an effort to meet marine conservation objectives. Research on the human dimensions of LMPAs is limited, though comprehensive policy analysis requires an understanding of the full range of social, cultural and economic benefits associated with LMPA designation. This paper addresses this need by employing a stated preference choice experiment survey of U.S. west coast households to examine public preferences for different protected area designs sited off the U.S. west coast. Using data from over 3000 randomly selected households in California, Oregon, and Washington we estimate choice models and calculate economic values for a suite of LMPAs that vary in size and in the types of restrictions within area boundaries. Results show that the LMPA size yielding the highest value is ~15.6% of the west coast Federal waters. Results also underscore the importance of restriction type, as there are considerably different threshold sizes above which diminishing returns and negative economic values are derived from no-access reserves, no-take, and multiple-use designations. While the value of any specific configuration can be estimated using the model, results offer insight on optimal use designations from a public perspective for small (< 2.5% of west coast Federal waters), medium (2.5%–~10%) and large (> 10%) LMPAs sited off the U.S. west coast.  相似文献   
18.
Abstract

Because of ever-growing demand for strategic metals, the focus of the international community has fallen on deep sea manganese nodules occurring at a water depth of more than 4500?m. We present an economic appraisal and strategy for mining of nodules from the Indian Ocean Nodule Field- one of the four economically potential areas in the world oceans. In contrast to the prevailing perception of non-viability of nodule mining, our analysis indicates a fair degree of economic feasibility and commercial sustainability to mine the deep-sea manganese nodules.  相似文献   
19.
A large deposit of low-grade kaolinite is occurring within the rocks of Lower Vindhyan Supergroup southwest of Chittaurgarh, Rajasthan. The deposit is being utilised by open-cast, manual to semi-mechanised methods of mining. Kaolinite produced is being marketed without processing. Earlier, nearly 60% of the kaolinite produced from the area was consumed by cement industries, but in recent past, utilisation of low-grade kaolinite has been minimised by cement industries in production of ordinary cement and hence its production has significantly declined. Mineralogical studies reveal that kaolinite is the main clay-mineral and quartz, calcite, iron-oxides and biotite are present as non-clay minerals in clay deposit of the area. Chemical analysis of the kaolinite show that alumina ranges from 15 to 35% while, silica and iron varies from 51 to 78% and 0.25 to 2.50% respectively.  相似文献   
20.
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