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71.
Coral reefs provide a multitude of goods and services, some of which are difficult to value due to their intangible nature and the absence of markets to ascribe their relative worth. The coral reefs of Sodwana Bay on the northeast coast of South Africa provide several ecological goods and services, of which only two are considered here: namely, sediment generation and sediment entrapment. Both are deemed essential to the functioning of the Sodwana Bay economy. The replacement-cost method was used to estimate the annual financial cost of sediment provided to the study area if it were replaced by dredging. Sediment generation by the coral reefs was valued at R2.6–R4.8 million, and sediment entrapment valued at R71.8–R84.6 million, totalling between R74.4 million and R89.4 million (≈$5.6–$6.7 million, at R13.38/US$1) per year.  相似文献   
72.
在开展地质灾害变形监测的过程中,由于传感器采集数据结果会受到客观环境的影响而出现异常情况,导致对变形情况的监测结果与实际情况存在较大误差,为此,提出基于多传感器估值融合理论的地质灾害变形监测方法研究。在对多传感器数据进行预处理阶段,引入了估值融合理论,具体采用的融合算法为最小误差均方差法,利用其对传感器采集数据结果中的异常值进行校正。在变形监测阶段,充分利用了多个数据源(传感器)对同一目标进行观测时的特征构成,结合观测特征、实时状态数据与发展函数三者之间的关系,实现对地质灾害变形情况的有效监测。在测试结果中,设计方法能够获取某地铁隧道水平方向上和垂直方向上的位移结果,具有较高的可靠性和精度。  相似文献   
73.
74.
Despite increasing attention paid to the value of marine resources, in particular marine protected areas (MPAs), their economic valuation focuses mainly on use values of ecosystem services such as fishery and tourism. Furthermore, most MPA related studies are carried out for coastal ecosystems, especially tropical coral reefs. The valuation of remote marine ecosystems is rare. The main objective of this paper is to estimate public willingness to pay (WTP) for alternative management regimes of a network of offshore MPAs in the North Sea under the Marine Strategy Framework Directive (MSFD). In a baseline valuation study carried out just before the adoption of the MSFD, beach visitors and a random sample of coastal and non-coastal residents were asked for their preferences for two alternative management options of three remote, ecologically sensitive areas with multiple use conflicts. Despite the lack of public awareness and familiarity with the offshore marine areas, a majority of 70% is willing to pay extra tax for their protection. Using a conservative value elicitation procedure, Dutch households are willing to pay on average maximum 0.25% of their annual disposable income to ban access and economic use. This serves as an indicator of what a network of remote MPAs in the MSFD is allowed to cost according to the Dutch tax payer.  相似文献   
75.
条件价值评估法在公众气象效益评估中的应用研究   总被引:1,自引:0,他引:1  
王桂芝  李廉水  黄小蓉  夏平嵩  李洁 《气象》2011,37(10):1309-1313
条件价值评价法(CVM)是目前生态(环境)经济学中最重要的和应用最为广泛的公共所有物价值的一种评估方法,对自然资源价值进行量化评估方面具有独特的优势,通过问卷调查反映环境影响下的价值问题,是一种理论化极强的评价方法。现将该方法应用到公共气象服务效益评估建模中,在考虑CVM不确定性因素的前提下,对公众气象服务效益进行评估,构建公众气象服务效益评估二分Logistic模型,并与传统的自愿付费法进行比较。采用全国抽样问卷调查数据量化结果比较表明,用二分Logistic模型对全国公众气象服务效益进行定量评估会更客观。  相似文献   
76.
克里金插值是一种进行局部估值的方法,但它并不能对局部的地质特征进行智能分析.因此,在很多时候其插值结果不能体现数据的一种局部异构特征.针对这一问题,提出了一种专家克里金插值法,这种方法是在普通克里金插值法的基础上加入专家地质知识,使得插值结果更能符合实际的地质情况.对该方法的原理、模型进行了详细的论述,并通过实例验证该方法的有效性.  相似文献   
77.
袁瑞娟  李凯琳 《地理科学》2018,38(7):1183-1188
以流经浙江北部的重要河流东苕溪流域为研究区域,从社会效益的视角,遵循意愿调查评估法的思想和技术,估算东苕溪流域居民对水质改善的支付意愿金额,分析影响支付意愿的主要因素。结果发现:357份有支付意愿,占问卷的65.9%,支付意愿范围为104.01~128.54元,中位数的支付意愿为115.63元/(a·户); 185份零支付愿意,占问卷的34.1%。其中影响流域居民支付意愿度的主要因素为:水质改善应为政府或企业的责任,流域居民不应是水质改善的承担者。同时,家庭人口数、文化程度、是否知道其饮用水源来自东苕溪与支付愿意度成正相关,对自家自来水状况的评价与支付意愿成负相关。基于此,研究提出适当增加水费用于水质改善;建立水环境信息制度,引导广大居民参与决策;严格执行环保标准,减少企业污染物排放等建议。  相似文献   
78.
Wetlands are known for their water filtration (or purification) function. Although different wetland types differ in their filtration capacity, they are usually aggregated together in economic valuation studies. Here, we explicitly separate the valuation of the suspended sediment and phosphorus (P) filtration services of the four major wetland types—bogs, fens, marshes and swamps—found in southern Ontario, Canada. The areal extents of the four wetland types are derived from the Canadian Wetland Inventory (CWI) progress map, while the sediment accretion rate is used as the key variable regulating the suspended sediment and P filtration functions. Based on available literature data, we assess the relationship of the sediment accretion rate to wetland size. Because only weak positive correlations are found, we assign a mean (average) sediment accretion rate to each wetland type. The sediment accretion rates are combined with mean soil P concentrations to estimate Pretention rates by the wetlands. The replacement cost method is then applied to valuate the sediment and P filtration services. The unit values for both sediment and P retention decrease in the order: marshes > bogs ≈ swamps > fens. The total value of sediment plus phosphorus removal by all wetlands in southern Ontario amounts to $4.2 ± 2.9 billion per year, of which about 80% is accounted for by swamps. We further assess the costs of different options to offset the additional P loading generated in a hypothetical scenario whereby all wetlands are converted to agriculture. The results demonstrate that replacing the P filtration function of existing wetlands with conventional land management and water treatment solutions is not cost-effective, hence reinforcing the importance of protecting existing wetlands.  相似文献   
79.
The Marine Strategy Framework Directive (MSFD) requires EU member states (MS) to develop and implement marine strategies containing programs of measures to protect and preserve the marine environment. Prior to their implementation, impact assessments, including Cost-Benefit-Analyses (CBA), need to be carried out. While the costs of introducing such measures are often relatively easy to determine, the economic valuation of the benefits derived from environmental improvements is much more challenging, particularly in the marine context. Still, it remains an important prerequisite for conducting CBA. The aim of this paper is to evaluate to what extent benefits can be quantified for use in CBA focusing on the German marine waters. The results indicate that there are still considerable gaps in the scientific knowledge about many of the pressures mentioned in the MSFD. Moreover, few economic studies exist that evaluate the benefits of marine protection measures, and many of them are not applicable in the German context. In addition, there is the risk that some benefits accruing from marine protection measures are systematically omitted in CBA. This raises the question to what extent comprehensive CBAs as required by the MSFD are possible in Germany, but also in other EU MS.  相似文献   
80.
Marine Protected Areas (MPAs) are a cost-efficient and management-effective tool. Fishery Resource Conservation Zones (FRCZs) are one type of MPA in Taiwan, and they were designated to ensure the sustainability of fishery resources since 1976; however, government appropriations are the only financing source for FRCZs, leading to manpower and equipment shortages for FRCZ management. This study selected the Touching and Suao FRCZs in Yilan County of Taiwan as cases studies. To assess the feasibility of establishing a sustainable financing mechanism for MPAs, the Contingent Valuation Method (CVM) was applied to examine respondents׳ willingness to pay (WTP) to setup a fund for FRCZ management. The empirical results indicated that approximately 90% of respondents would be willing to donate funding for MPAs, and the WTP per respondent is NT$586.51 (US$19.6). Thus, establishing an MPA fund is a feasible way to operate Taiwanese MPAs through a co-management framework involving the central government, local government, local communities and stakeholders. However, based on our empirical results, a co-management financing mechanism for MPAs should be established to ensure stable and diverse financing sources.  相似文献   
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