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111.
Although climate change is highly prevalent in the media, people in Europe and the United States are often unsure about climate change terms, processes, and its personal consequences. In other words, climate change communication seems to be largely failing so far. Among other communication tools, maps are widely used for explanatory purposes by scientists and the media. Here two questions arise: first, whether high map complexity may be too intricate to be understood and discourage people from deciphering the map; and second, whether personal interest in climate change can be influenced by the phenomenon depicted or the map’s scale. In a survey conducted among 109 students in the USA, 63% of respondents preferred a simple map, but a substantial subset, 37%, asked for complexity to receive more information. Regional phenomena evoked more concern than far-off phenomena (concern level index difference of 0.93 on a 5-ranked Likert scale). The advantage of maps showing local areas could not be statistically confirmed.  相似文献   
112.
多样化的数据内容和应用需求迫切需要建立导航电子地图内容自适应表达模型,进一步为用户提供个性化服务.本文以用户为中心,从用户需求的角度出发,通过分析用户的背景信息及其用图习惯等行为信息建立了导航电子地图内容自适应表达模型,并利用朴素贝叶斯算法进行模型匹配.研究并改进当前导航电子地图内容结构固化,模式单一的不足,为导航电子地图个性化发展提供一定的借鉴和指导.  相似文献   
113.
In recent years, a vibrant literature on urban informality has emerged in urban geography. A key claim of this literature is that informality is not only present in cities in the Global South, and that the concept can be usefully applied to understand important dimensions of urbanisation in cities in the Global North. In this paper, we apply insights from that literature to an examination of informality in Australian cities, as a means of deepening our understanding of changes currently underway in urban governance and politics. Drawing on that literature and our own research into informal practices in Australian cities, we examine the forces that help to produce informality, the diverse forms and agents of informality, the forms of authority that they enact, and their relationship to formal economies, regulations and politics. We use examples of informal housing, informal labour, do-it-yourself music venues, graffiti and its regulation, food foraging, and queer community building in Sydney to illustrate our arguments. We conclude by reflecting on the lessons learnt across these diverse cases for our understanding of urban governance and politics in Australia, and offer an agenda for further research on this issue.  相似文献   
114.
中国城乡居民创业意愿的空间差异及其影响因素   总被引:2,自引:1,他引:1  
施帆  张佳  王琛 《地理研究》2020,39(8):1852-1863
创业意愿受区域环境的影响。利用中国家庭大数据和中国家庭金融调查,运用多层混合效应logistic模型,从区域创业示范效应、教育背景和风险偏好三方面探讨城乡创业意愿影响因素的差异。研究发现:① 区域示范效应促进东部城市居民创业意愿产生,但对中西部城市及农村居民无显著影响。② 城市中高学历居民更难产生创业意愿,东部农村居民创业意愿与教育背景无关,在中西部农村,高学历促进创业意愿产生。③ 城市中偏好高风险、高收益的居民更可能产生创业意愿,但当居民风险容忍度高到一定程度后,产生创业意愿的可能性不再改变,且东部城市的容忍程度门限高于西部城市;而在农村,偏好更高风险不能促进创业,仅当居民不愿承担任何风险时才会抑制创业。  相似文献   
115.
We used Argos‐linked Fastloc‐Global Positioning System (Argos‐linked Fastloc‐GPS) satellite tags to investigate how loggerhead sea turtles use neritic foraging habitats at multiple scales. Out of 24 turtles, six individuals used more than one foraging site, with all sites being separated by >25 km. These six individuals used up to four sites, remaining at each site for a mean of 150 days and returning to the same site a minimum of 52 days later. The other 18 turtles remained in a single site. The area within sites was not used uniformly, with 15 out of 24 turtles exhibiting complex movement patterns within and amongst up to five focal patches, which were typically 0.1–5.0 km apart within a single site. Movements between sites and patches might sometimes have reflected overwintering behaviour; however, similar movement patterns occurred at multiple times of the year, suggesting other factors were also involved. Use of multiple sites and patches might be driven by differences in resource availability, such as food and/or night‐time refuges, competition, or exploratory movement to investigate or locate alternative patches. We confirmed competition via direct visual observations of aggressive interactions between individuals at one foraging patch. Our results illustrate the importance of standardizing data to the same number of locations per day and night to accurately delineate key areas used by turtles or for evidence‐based marine protected area planning.  相似文献   
116.
As a key species of the Southern Ocean ecosystem,the thermal and saline tolerances of Antarctic krill(Euphausia superb a Dana)are relatively unknown because of the challenging environment and complicated situations needed for observation have inhibited in-situ experiments in the field.Hence,the thermal and saline tolerance of krill were examined under in-situ aquarium conditions with different controlled scenarios.According to the experiments,the critical lethal times of krill were 24h,2h and 0.5h under 9℃,12℃,and 15℃,respectively,and the estimated 50%lethal times were about 17.1 h and 1.7 h under 12℃and 15℃,respectively.Additionally,the critical lethal times(the estimated 50%lethal times)of krill were approximately 14h and 0.5h(about 22.9 h and 1.7 h)of salinity under 19.7 and 15.9,respectively.The observed critical and 50%lethal times of krill were 0.5 h and approximately 1.4 h,respectively,salinity under 55.2.The critical and 50%lethal temperatures of krill were 13℃and approximately 14.2℃,respectively.Additionally,the critical and 50%lethal salinity was 19.6 and approximately 17.5 for the lower saline(below normal oceanic salinity[34.4])environment and 50.3 and approximately 53.2 for the higher saline(above 34.4)environment,respectively.The upper thermal and saline preferences of krill can be considered 6℃and 26.8 to 41.2,respectively.These results can provide potential scenarios for predicting the possible fate of this key species in the Southern Ocean.  相似文献   
117.
超大型矿床数量有限,只占世界矿床总数的一小部分,但储量和开采量对于全世界的总储量和总开采量来说占有十分显赫的位置。它展示的某些地质特征是中小型矿床不具备的。世界上大部分金属主要含于大型、超大型矿床中,它在国民经济发展中却占有十分重要的地位。寻找超大型矿床已是刻不容缓,对超在型矿床的分布、特征、成因各方面的研究则是找矿的一个重要的基础。  相似文献   
118.
Valuing multi-attribute marine water quality   总被引:1,自引:0,他引:1  
The marine environment provides many goods and services that depend on the quality of coastal waters. In this paper, we represent water quality by three different attributes, coastal cod stock level, bathing water quality, and biodiversity level, and carry out a choice experiment among residents on the Swedish west coast to estimate the economic benefits of improved coastal water quality. We find that respondents have high levels of environmental concern and that substantial values are at stake. The highest values were placed on preventing further depletion of marine biodiversity and to improve Swedish cod stocks.  相似文献   
119.
120.
条件价值评估法的发展与应用   总被引:115,自引:2,他引:115  
环境物品或生态系统服务的经济价值评估是国际上生态经济学、环境经济学研究的前沿领域。由于绝大多数环境物品或生态系统服务的公共物品特性,其经济价值的评估需要运用非市场的价值评估技术。条件价值评估法(CVM)是非市场价值评估技术中应用最广、影响最大的一种方法。详细介绍了国际上CVM及其发展与应用研究的现状,分析了CVM在环境价值评估技术中的地位及其理论基础,总结了最大支付意愿(WTP)的各种引导技术,全面归纳了CVM研究中可能出现的各种偏差及其相应的解决方法,简要介绍了最大支付意愿的数据统计分析方法。  相似文献   
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