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排序方式: 共有1007条查询结果,搜索用时 15 毫秒
61.
Nehal Karim 《Natural Hazards》1995,11(3):247-258
This paper deals with various types of natural disasters which occur very frequently in Bangladesh. Disaster can occur at any time, in any place, in any dimension, and may owe as much to the circumstances as to the scale of the event. With the exception of the man-made disaster of war, famine, fire, pollution, accident and civil strife, the worst disasters follow natural events.Bangladesh is widely known as a land of natural disasters and is highly vulnerable to flood, cyclone and river erosion. By the effects of these disasters the country is now permanently in distress. These disasters have become a regular phenomenon and cause suffering to millions of people of the country since many decades. Besides, it also focuses on policy options concerning disaster management. 相似文献
62.
本文采用类比法和定量化方法对上海宝山区村镇民房震害损失进行了预测。在此基础上,对上海已有的和新建的民房提出抗震对策和措施。 相似文献
63.
ABSTRACTWater indicators and indices are useful tools to assess river basin performance, that is, to measure whether the basin operates satisfactorily under a wide range of possible future demands and hydrological conditions. Spanish regulations assess the performance of water demands by using reliability indicators (RIs), established by law in 2008. This article raises the possibility of updating RIs by comparing them with sustainability indicators (SIs). SIs are widely used for the assessment of river basin performance and several policy scenarios. We applied a water allocation model to the Guadiana River basin in Spain to compare indicators under three scenarios. The study was framed within the science of socio-hydrology, combining the physical environment of a water system with its influence on social aspects. SIs gave better results than RIs when comparing future scenarios. We also propose the introduction of a vulnerability indicator into Spanish regulations. 相似文献
64.
65.
Main concepts of the "European approach" to karst-groundwater-vulnerability assessment and mapping 总被引:4,自引:1,他引:3
D. Daly A. Dassargues D. Drew S. Dunne N. Goldscheider S. Neale I. Popescu F. Zwahlen 《Hydrogeology Journal》2002,10(2):340-345
In order to achieve some consistency in the establishment of groundwater intrinsic vulnerability maps in Europe, a new approach
is proposed by Working Group 1 of the European COST Action 620 on "Vulnerability mapping for the protection of carbonate (karst)
aquifers". A general procedure is offered which provides consistency while allowing the required flexibility for application
to a continent and under conditions of varying geology, scale, information availability, time, and resources.
The proposed methodology is designed to be clearly more physically based than the existing vulnerability-mapping techniques.
It takes the specificity of the karstic environments into account without necessarily excluding the applicability to other
geological conditions. Combined "core factors" for overlying layers and for concentration of flow account for the relative
protection of groundwater from contamination while taking into account any bypass of the overlying layers.
A precipitation factor is distinguished for describing characteristics of the input of water to the system. Differentiation
is made between groundwater resource intrinsic vulnerability mapping and source intrinsic vulnerability mapping. For the latter,
a factor describing the karst network development is relevant. This short technical note describes a first step in the work
program of Working Group 1 of the COST Action 620. Future steps are now in progress to quantify the approach and to apply
it in various European pilot areas.
Electronic Publication 相似文献
66.
67.
Joseph R. Oppong 《The Professional geographer》1998,50(4):437-448
Ten years after the human immuno-deficiency virus (HIV) was first reported in Ghana, it continues to spread throughout the country following patterns that are rare in other African countries. HIV is seen in twice as many females as males, more frequently in rural than urban regions, and regions with high rates of polygamy have significantly lower rates. The evidence presented in this paper shows that HIV diffusion patterns probably reflect the spatial distribution and social networks of vulnerable social groups. While information-based campaigns are still necessary in the fight against HIV/AIDS, they fail to enable or empower vulnerable people to protect themselves against infection. 相似文献
68.
Development of Seismic Risk Scenarios Based on a Hybrid Method of Vulnerability Assessment 总被引:11,自引:5,他引:6
A hybrid methodology of vulnerability analysis is presented, involving elements from both empirical and theoretical methods. A model for correlating analytically calculated structural damage indices to loss (in monetary terms) is also proposed and calibrated against available statistical data. Probability damage matrices derived using this methodology are incorporated into a cost-benefit model tailored to the problem of estimating the feasibility of seismically rehabilitating the existing stock of reinforced concrete buildings in Thessaloniki, Greece. Losses calculated using the suggested procedure are found to be in good agreement with losses incurred during the 1978 Thessaloniki earthquake. The results of the present study also indicate that benefit/cost ratios for reinforced concrete buildings are quite low. Hence, it appears that a pre-earthquake strengthening programme is not economically justifiable. 相似文献
69.
Fred W. Krüger 《GeoJournal》1998,46(2):79-87
Namibia and Botswana differ from other sub-Saharan nations in their record of stable political performance. However, both
countries have to face increasing social problems. In the case of Namibia these are still mainly related to the process of
post-apartheid national reconciliation and identity building, in the case of Botswana they refer to issues of growing tribal
tensions and of a gradual interior restructuring of society. This paper analyzes the various patterns of social transformation
in the two countries and examines in what ways state-society relations are different from other African nations.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
70.
岷县地形多变、地貌多样、地质环境复杂,近年来地震、滑坡等地质灾害多发。基于易损性影响因素,结合岷县具体情况,选取人口密度、国内生产总值、公路、房屋、林地和耕地6个指标,以乡镇为基本单元,利用模糊综合评判法构建评价体系,将研究区易损性划分为不同等级。结果表明,高易损性地区占研究区总面积的20.62%,中易损性地区的占比为19.90%,低易损性地区的占比为37.25%,极低易损性地区的占比为22.23%。将易损性结果与地质灾害历史灾害点进行叠加分析发现,中易损性和高易损性地区的历史灾害占灾害总数的50.53%,为岷县防灾减灾工作提供了新的思路和参考。 相似文献