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521.
The intersections between technology, mobility and citizenship have been relatively neglected in current geographical enquiry. Through qualitative analysis of user, operator and media accounts of retro-fitted safety technology on HGVs (Heavy Goods Vehicles), this paper illustrates the ways in which citizenship as a moral accomplishment is dependent upon the socio-technical worlds into which individual actors are folded. In response to the growing incidence of cyclist fatalities under the wheels of HGVs, various safety technologies have been positioned as reliable ‘intermediaries’ by policymakers, manufacturers and operators seeking to mitigate the risks of the HGV. However, we demonstrate that these technologies are more accurately seen as ‘mediators’, because of the ways in which they distort and translate information, producing and reshaping new tasks and roles for HGV drivers. One of the consequences of this is a shift in responsibility towards the drivers, which increases the potential to construct them as negligent if accidents still occur. Accordingly, we indicate how technologies ‘push back’ on mobile subjects, shaping not only their ability for moral conduct, but broader social identities as citizens.  相似文献   
522.
Military activities have produced contaminated environments at many sites around the world. This contamination and the associated health risks play a large role in how these places can be redeveloped after military use. In this essay we focus on the island of Vieques, Puerto Rico which was used as a bombing range by the US military for six decades until 2003. We examine the ways different groups of people perceive this formerly militarized landscape and the ways that these perceptions legitimatize certain redevelopment options over others. Through participant observation, semi-structured interviews and an analysis of textual materials we found that many local residents view the island as suffering from severe contamination while the large number of visitors, tourism promoters and North Americans now flocking to the post-militarized Vieques view it quite differently. These perceptions of purity and contamination, affected by different knowledges of the island’s history, have led to differing valuation of the landscape and contentious economic, political, and cultural battles over an island often labeled “natural” despite a history of military use and social exclusion.
Jeffrey Sasha DavisEmail:
  相似文献   
523.
利用河北省棉区1981—2015年40个气象站逐日气象资料、农业气象观测站棉花农情、连阴雨灾情、棉花产量资料,分析连阴雨过程特征及其对棉花生长的影响,修订和完善连阴雨灾害指标;采用数理统计方法获取历史连阴雨产量灾损率、筛选关键致灾因子,采用权重系数法构建连阴雨强度指数,并建立基于强度指数的灾损评估模型;利用有序样本聚类分析法划分连阴雨强度等级;依据风险分析原理,构建连阴雨风险指数并进行风险区划。结果表明:建立的强度指数能够客观反映连阴雨灾害强度,灾损评估模型评估效果较好。棉花播种出苗期连阴雨发生概率低(0.076)、造成的损失小(平均产量灾损率0.09%);现蕾至吐絮期连阴雨影响较大,发生概率和造成的灾损率由大到小依次为花铃期(0.447,17.1%) > 现蕾期(0.394,11.7%) > 吐絮期(0.237,7.2%)。近年来,现蕾期连阴雨发生站次减少,对棉花影响减弱,花铃期和吐絮期发生站次增加,尤其是吐絮期增加明显,成为连阴雨灾害影响棉花生长的主要时期。现蕾期和花铃期连阴雨高风险区主要分布在非主棉区,其中现蕾期高风险区分布在保定北部及以北棉区,花铃期高风险区分布在保定北部及以北棉区和石家庄、邢台、邯郸三市西部棉区;吐絮期高风险区分布在保定西南部、衡水西部、石家庄及其以南棉区,部分地区为主棉区。  相似文献   
524.
利用暴雨区连续追踪的思路和全国2481个气象站逐日降水资料对1961—2019年全国区域连续性暴雨过程(Regional Continuity Rainstorm Process,RCRP)进行客观识别,并根据RCRP的持续时间、影响范围、最大日降水量和最大过程降水量建立和改进危险性评估模型和危险性区划。结果显示:1961—2019年中国共发生2294次RCRP,危险性排名前十强的RCRP与历史记录相符;其危险性空间分布特征与我国降水气候态分布相似,由东南向西北逐级递减;我国RCRP的高危险性区域位于华南和江南地区;危险性的季节空间分布与同季节的降水特征相关,春季华南地区的RCRP高危险性等级体现了我国华南前汛期的影响;夏季华北和东北地区的RCRP危险性高于其他季节,沿海地区的高危险性体现了台风暴雨的影响;秋季四川北部的危险区主要体现了华西秋雨的影响;单次RCRP危险性区划表征本次暴雨洪涝受灾程度大小的分布情况,可以直观地判断此次RCRP对我国相应区域造成暴雨洪涝灾害的大小分布情况。其研究结果增进了对于RCRP演变规律的认识,对于预测未来RCRP季节或次季节内等不同时间内的区域危险性强度大小及其相关的暴雨洪涝灾害风险防范具有重要意义。  相似文献   
525.
IPCC第六次评估报告(AR6)第二工作组(WGII)报告的第二章表明,气候变化对陆地和淡水生态系统影响的范围和程度较前期评估结果更为严峻。人为气候变化导致生态系统结构、功能和恢复力恶化,生物群落转移,疾病的传播范围和发病率增加,野火燃烧面积增加和持续时间延长,局部地区物种灭绝,极端天气的频率和强度增加。未来气温升高2~4℃情景下,陆地和淡水生态系统中高灭绝风险物种占比为10%~13%,野火燃烧面积增加35%~40%,森林地区50%以上树木面临死亡风险,15%~35%的生态系统结构发生转变,碳损失持续增加,气温的升高将进一步加剧这些风险造成的严重且不可逆的影响。通过生态系统保护和恢复等人为适应和减缓措施,可以在一定程度的气候变化范围内保护生态系统的生物多样性并增强生态系统服务在气候变化下的恢复力。加剧的气候变化将阻碍适应措施的制定和实施,为保证措施的有效性需要考虑气候变化的长期影响并加快适应措施的部署。  相似文献   
526.
基于自然灾害风险评估理论,利用2005—2019年辽宁省1639个自动站逐时降水观测资料、2017年辽宁省30 m分辨率的基础地理信息和山洪沟资料以及风险普查数据,对辽宁暴雨诱发山洪灾害风险区划进行研究,并将风险区划结果与历史山洪灾情进行对比分析。结果表明:通过山洪灾害与降水相关性统计发现,6 h暴雨作为辽宁省山洪致灾因子更为合适,因此构建了6 h综合利用分级暴雨强度及暴雨频次精细评估暴雨致灾危险性;山洪沟沟口高程、沟床比降及河网密度等资料可有效评估山洪孕灾环境敏感性;人口密度、耕地比例两个风险暴露度指标以及灾损敏感系数可大体评估承灾体的易损性;与历史山洪灾害空间和频率分布对比,山洪灾害的高发区与在本次风险区划高风险区基本吻合;精确到每个山洪沟风险区划的结果,提高了山洪灾害的风险区划精度,为辽宁暴雨诱发山洪灾害精准防御提供参考。  相似文献   
527.
Crop and livestock farmers must respond to climate change, including a range of physical and cultural impacts and risks. In rural northern California, farmers face extreme drought and catastrophic wildfires with increasing frequency. I draw on an extended case study of farmers and agricultural advisors in Siskiyou County to understand how rural agriculturalists perceive risks when navigating climate change discourses. While farmers are changing their management practices in response to the physical effects of climate change, many perceive substantial social risks within their communities if they align themselves publicly with climate change beliefs or actions. Perceived social consequences included loss of access to the benefits of membership in formal and informal farming groups. Efforts focused on educating or convincing farmers of climate science may, in some contexts, increase rather than decrease the perceived social risks of climate action. The framing of climate policies, programs, and practices – especially by public agricultural advisors like Cooperative Extension Advisors and local USDA staff (e.g., Farm Service Agency) – is important not only for increasing farmer participation, but also for reducing perceived social risks associated with climate change. Interventions that focus on livelihood impacts and validate existing land stewardship-oriented values have more potential to increase the pace and scale of climate change mitigation and adaptation in agriculture.  相似文献   
528.
Plastic pollution through small particles, so-called microplastics, is acknowledged as an environmental problem of global dimension by both politicians, and the public. An increasing number of environmental studies investigate the exposure and effects of microplastics. Although there are many open questions, current scientific evidence does not confirm a high risk for the environment. At the same time, the issue receives great public attention, which in turn motivates various political and policy actions. So far, little research has examined the underlying social dimensions, i.e., the factors explaining individual risk perception of microplastics. This paper studies the perception of risks associated with microplastics concerning the environment and human health using data from a representative online survey conducted in Germany (n = 1027). We particularly examine the role of socio-demographics, individual awareness, knowledge factors, and the media’s influence on risk perception. Our results show that a majority of the respondents rates the risks through microplastics very high for both the environment and human health. Regression analyses demonstrate that environmental awareness and knowledge of media narratives are the strongest predictors for this risk perception. Our study illustrates the incongruence between scientific knowledge, media framing, and the public opinion concerning the risk posed by microplastics.  相似文献   
529.
全球气候安全问题已经日益突显,为了开展气候安全风险管理,国内学术界最近提出了气候容量的概念。然而,目前对气候容量的科学认识十分有限,甚至还没有比较统一的科学定义,对如何通过气候容量评价开展气候安全风险管理也没有明确的技术思路。在归纳总结以往研究的基础上,进一步讨论了气候容量及其对气候安全风险管理的作用,对气候容量给出了更加科学的定义和合理的诠释,并且分析了气候容量的科学属性和基本特征,探讨了全球气候安全风险的总体趋势,提出了利用气候容量的杠杆作用提升气候安全风险管理和气候资源开发利用水平的初步思路。这对推进我国气候业务对国家非传统安全的服务能力具有科学参考作用。  相似文献   
530.
Pockmarks form where fluids discharge through seafloor sediments rapidly enough to make them quick, and are common where gas is present in near-seafloor sediments. This paper investigates how gas might lead to pockmark formation. The process is envisioned as follows: a capillary seal traps gas beneath a fine-grained sediment layer or layers, perhaps layers whose pores have been reduced in size by hydrate crystallization. Gas accumulates until its pressure is sufficient for gas to invade the seal. The seal then fails completely (a unique aspect of capillary seals), releasing a large fraction of the accumulated gas into an upward-propagating gas chimney, which displaces water like a piston as it rises. Near the seafloor the water flow causes the sediments to become “quick” (i.e., liquefied) in the sense that grain-to-grain contact is lost and the grains are suspended dynamically by the upward flow. The quickened sediment is removed by ocean-bottom currents, and a pockmark is formed. Equations that approximately describe this gas–piston–water-drive show that deformation of the sediments above the chimney and water flow fast enough to quicken the sediments begins when the gas chimney reaches half way from the base of its source gas pocket to the seafloor. For uniform near-surface sediment permeability, this is a buoyancy control, not a permeability control. The rate the gas chimney grows depends on sediment permeability and the ratio of the depth below seafloor of the top of the gas pocket to the thickness of the gas pocket at the time of seal failure. Plausible estimates of these parameters suggest gas chimneys at Blake Ridge could reach the seafloor in less than a decade or more than a century, depending mainly on the permeability of the deforming near-surface sediments. Since these become quick before gas is expelled, gas venting will not provide a useful warning of the seafloor instabilities that are related to pockmark formation. However, detecting gas chimney growth might be a useful risk predictor. Any area underlain by a gas chimney that extends half way or more to the surface should be avoided.  相似文献   
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