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971.
人口地理信息系统的研制 总被引:4,自引:0,他引:4
提出了人口地理信息系统的层次结构、功能,并对人口地理信息系统的研制进行了详细的探讨。 相似文献
972.
There are limitations in conventional earthquake loss procedures if attempts are made to apply these to assess the social and economic impacts of recent disastrous earthquakes. This paper addresses the need to develop an applicable model for estimating the significant increases of earthquake loss in mainland China. The casualties of earthquakes were studied first. The casualties of earthquakes are strongly related to earthquake strength, occurrence time (day or night) and the distribution of population in the affected area. Using data on earthquake casualties in mainland China from 1980 to 2000, we suggest a relationship between average losses of life and the magnitude of earthquakes. Combined with information on population density and earthquake occurrence times, we use these data to give a further relationship between the loss of life and factors like population density, intensity and occurrence time of the earthquake. Earthquakes that occurred from 2001 to 2003 were tested for the given relationships. This paper also explores the possibility of using a macroeconomic indicator, here GDP (Gross Domestic Product), to roughly estimate earthquake exposure in situations where no detailed insurance or similar inventories exist, thus bypassing some problems of the conventional method. 相似文献
973.
Dmitri Piterski 《GeoJournal》1997,43(4):385-388
The author examines the recent situation in the development of cities in Russia. Recent trends include a lack of growth and even a decrease in population; extensive economic restructuring; a grave ecological situation in cities; and recent peculiarities in the geopolitical situation and population migration. Due to the new economic, demographic, geopolitical and social situation in Russia it is necessary to re-evaluate the prospects for the development and growth of the big cities in this country. The system of basic documents for regional and city planning in the former USSR and in Russia includes different stages: from The General Scheme for the Settlement Systems of the Country and The Regional Territorial Complex Schemes of Environmental Protection in different regions to the detailed plans for the different parts of cities and towns. The shortcomings of this system and in the process of the realization of the schemes of regional planning and general plans for cities are documented. 相似文献
974.
论述了全球人口及城市人口增长与发展的基本规律,根据历史记录数据建立了其预测指数方程,预测结果表明,21世纪50年代全球人口将超过100亿;且其城市人口将于2025年发展为79亿。论证了人口高速增长与全球地质环境变化紧密相关。讨论了农业地质环境变化-谷物供应问题以及可耕土地资源减少和水土资源流失、沙漠膜问题及工业矿产、能源、资源与水资源紧缺以及其地质环境变化问题。相应于地质环境变化问题建立了预测方程 相似文献
975.
黄鼎成 《水文地质工程地质》1993,20(1):5-8
文章概述了我国正以历史上最为严峻的资源、环境状况,承载着历史上最多的人口群及其最大的活动能力。初步探讨了持续发展的必然选择。 相似文献
976.
The spatial properties of events in the 1997 Colfiorito–Sellano seismic sequence (Northern Apennines, Italy) were investigated using coherence, a parameter derived from seismic moment tensors that quantifies the kinematic similarity between focal mechanisms. The 1997 Colfiorito–Sellano seismic sequence predominantly consists of normal faulting earthquakes, with a few strike-slip and reverse faulting episodes. This kinematic heterogeneity is possibly related to the contemporaneous activity of two different sets of faults: NW–SE normal faults and NNE–SSW sub-vertical faults, the latter inherited from the previous Miocene compressional phase. The study used two independently-derived data sets of the same seismic sequence characterized by a different number of events and by different precision of spatial localisation. Their statistical significances, assessed through a reshuffling procedure, reveal that data sets with at least some hundreds of events and good positional precision are required to obtain significant results through coherence analysis. Results from the better quality data set indicate that this seismic sequence is characterized by a rapid decrease in the kinematic similarity between earthquake pairs within 2 km of separation, particularly along directions sub-perpendicular to the normal fault strike. The decrease rate seems to be controlled by the geometric characteristics of the normal faults, given that the mean along-dip distance between fault segments is 2 km. In proximity to pre-existing tectonic lineaments the relative abundance of strike-slip and reverse faults tends to decrease the kinematic similarity between events but does not influence the coherence decrease rate. The presence of mixed focal mechanisms (normal, reverse and strike-slip) in a single seismic phase implies that mixed fault types are not restricted to polyphase tectonic histories: such heterogeneous kinematics during a single phase may be induced by the presence of inherited discontinuities. 相似文献
977.
The mean center of population of the United States is a convenient location used to summarize the population distribution of the United States and how it changes over time. As computed by the U.S. Census Bureau, the center depends on an arbitrary choice of a map projection. We feel that this location should depend only on the population distribution and not on any choices made in representing the data of the distribution. This note discusses a method for computing this location that does not depend on any choices made and describes how the results of this method differ from those of the Census Bureau. 相似文献
978.
中国城市人口增长过程及差异研究 总被引:1,自引:0,他引:1
采用1984—2003年中国所有设市城市完整的人口规模数据,揭示该阶段中国城市人口增长过程的总体特征、等级差异特征及空间差异特征。分析认为:中国城市人口增长过程具有持续性和波动性的总体特征;在等级差异方面则表现为明显的阶段性特征,2000年前以中小城市增长为主,之后则以特大城市和大城市增长为主;人口增长过程存在显著的空间差异,最突出的是以东北三省为主的北方城市人口增长明显慢于全国平均水平,此外,新城市的人口增长明显快于原有城市。 相似文献
979.
新疆小城镇人口规模预测 总被引:1,自引:1,他引:1
小城镇人口的发展对新疆城镇化发展具有重要意义,其人口变动的各种信息将对新疆城镇的发展起到重要的参考作用。在对人口预测的主要方法进行比较的基础上,采用一元线性回归法、指数法、增长速度法和灰色系统GM(1,1)模型等对新疆小城镇2010、2015和2020年的总人口进行了预测。由于近年来新疆经济的加速发展,城镇化速度也将加快,小城镇人口将会出现较快的提高。故而,在综合考虑新疆小城镇人口发展的多种因素及未来新疆城镇发展趋势的基础上,针对各种预测方法的优缺点综合得出了新疆小城镇2010、2015和2020年的总人口数量。 相似文献
980.
Albert A. Bartlett 《Natural Resources Research》2006,15(3):151-164
This paper examines the implications of statements by Australia’s Minister of… Resources that Australia’s exports of coal
are growing rapidly and that Australia’s coal will last “110 years at current rates of production.” If one assumes that coal
production P(t), follows a Gaussian curve (similar to a Hubbert curve) one can construct a family of Gaussian curves showing possible future
paths of P(t) which are consistent with the cited “110 years.” Each curve reaches a maximum after which P(t) declines toward zero. Knowledge of the present value of dP/dt allows one member of the family to be identified as the most probable future path of P(t). Families of curves and tabular data are presented for resource quantities that would last 50, 100 and 200 years “at current
rates of production.” If, instead, Australia’s P(t) follows a declining exponential curve (exp(−kt)) with k = (1/110) per year, the stated quantity of coal will allow production to continue forever, with P(t) declining with a half life of 76 y. This and more rapidly declining exponential paths are the only paths that can be said
to be sustainable. The envelope of the family of Gaussian curves divides the (P, t) plane into “allowed” and “forbidden” areas.
The declining exponential curve divides the “allowed” area into an upper area that is “terminal” and a lower area that is
“sustainable.” These facts, coupled with Australia’s expectations of rapid growth of its population, suggest that Australia’s
present resource policies are “anti-sustainable” and that the people of Australia need to rethink their present policy of
rapidly exporting their fossil fuels. 相似文献