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71.
This paper examines the use of conservation easements, with a focus on California. Conservation easements are now the dominant tool used for private land conservation in the United States. Easements are in many ways a paradigmatic neoliberal environmental policy tool. They privatize and re-scale a great deal of land conservation decision-making authority; they are market-based; they provide financial incentives for participation rather than punishment for non-compliance; and they commodify new property rights. However, these neoliberalisms are incorporated in uneven, and sometimes contradictory, ways that emphasize the gulf between neoliberal ideologies and “actually existing neoliberalisms.” Most critically, as a result of extensive public funding and management, conservation easements are not nearly as private (and thus not as neatly neoliberal) as they sometimes seem. Conservation easements are often heralded as a “win–win” land conservation strategy. I argue that the extent to which conservation easements may be construed as win–win solutions depends a great deal on who is included in the calculation of winners and losers. I contend that using and governing easements as if they are private elides complex questions about larger public costs and benefits. This obscures the large number of people and institutions (both state and private) that will likely need to be involved in governing conservation easements in the long term. 相似文献
72.
Gillad Rosen 《Urban geography》2017,38(4):606-625
The City of Toronto has undergone a number of dramatic transformations in the last several decades morphing from an industrial-driven metropolis into a thriving real estate and consumer amenities market. Over these decades, the development of condominiums has significantly transformed Toronto’s cityscape surpassing by far other types of real estate development. Based chiefly on a series of interviews with property developers and local politicians, this article explores development from the perspective of condo developers. The article identifies the key condo developers and categorizes them according to their development approaches and spatial preferences. Findings reiterate the need to consider property developers as highly diverse and flexible place entrepreneurs. Differences play out not merely in preferred development location and size, but also in target population, tenure mix, corporate structure, and the extent to which capitalism and economic gain are mixed with more idealistic motivations such as social benefits. 相似文献
73.
Arne Schnack-Friedrichsen Angela M. Davis Jim D. Bennell Dei G. Huws 《Marine Georesources & Geotechnology》2001,19(4):221-243
The interdependence between the seismo-acoustic properties of a marine sediment and its geotechnical/physical parameters has been known for many years, and it has been postulated that this should allow the extraction of geotechnical information from seismic data. Though in the literature many correlations have been published for the surficial layer, there is a lack of information for greater sediment depths. In this article, a desktop study on a synthetic seafloor model illustrates how the application of published near-surface prediction equations to subsurface sediments (up to several tens of meters burial depth) can lead to spurious predictions. To test this further, acoustic and geotechnical properties were measured on a number of sediment core samples, some of which were subjected to loading in acoustically-equipped consolidation cells (oedometers) to simulate greater burial depth conditions. For low effective pressures (representing small burial depths extending to around 10 meters subsurface), the general applicability of established relationships was confirmed: the prediction of porosity, bulk density, and mean grain size from acoustic velocity and impedance appears generally possible for the investigated sedimentary environments. As effective pressure increases through, the observed relationships deviate more and more from the established ones for the near-surface area. For the samples tested in this study, in some instances increasing pressure even resulted in decreasing velocities. There are several possible explanations for this abnormal behavior, including the presence of gas, overconsolidation, or bimodal grain size distribution. The results indicate that an appropriate depth correction must be introduced into the published prediction equations in order to obtain reliable estimates of physical sediment properties for greater subsurface depths. 相似文献
74.
《Geoforum》2017
In Vietnam, initial programs to Reduce Emissions from Deforestation and Forest Degradation (REDD+) have proliferated through international finance and new governance regimes for climate change mitigation. National capacity and legal frameworks have been adjusted to make the country eligible for REDD+ financing. In some local areas, activities have been implemented to ‘produce’ carbon credits intended for the international voluntary carbon market. Through a case study of a pilot REDD+ project in the Central Highlands of Vietnam, we examine how REDD+ has intersected with property rights institutions and agrarian change to influence changing property relations and commodity markets. Our findings show that REDD+ implemented through state and local institutions has articulated with the local political economy to coproduce conditions that embody local norms, needs, and desires. Specifically, local actors negotiate state-sanctioned tenurial instruments used for REDD+ governance, not for the purposes of carbon sequestration but instead in order to reassert their rights to land and forest for the cultivation of boom crops—the antithesis of REDD+ objectives. In the fine balancing act of adjusting local forestland holdings, REDD+ implementation has effectively facilitated increased opportunities for upland villagers to strategically claim land titles from local political authorities in the form of communal land certificates for forests called ‘Red Books’. In securing communal Red Books, villagers redefine or co-constitute the purpose of REDD+ to secure land for cash crop and commercial timber production. As with other forms of environmental governance, REDD+ is thus co-constituted locally in line with state and local institutions and histories and present day realities. 相似文献
75.
76.
In this ‘Thinking Space’ essay we revisit Maurie Daly’s 1982 book Sydney Boom, Sydney Bust, fuelled by concern for how Australian cities are being transformed by financialised real estate. Daly's insights remain highly relevant to Sydney and other cities around Australia and the world today. Poorly planned densification, inflated property markets, land speculation, and housing poverty are all outcomes of the (global) capitalist intersection of finance and land in Australia. The overwriting of Aboriginal country with colonial-capitalist systems of land ownership set in train a process of land and housing booms, bubbles and busts that are better understood by their circular continuity rather than as a set of ephemeral ruptures. It is the property and finance system itself, rather than any ruptures to it, that reproduces unequal and alienating social relations. Researchers investigating property speculation, global capital, urban planning and financialisation, we argue, ought to revisit this key text to inform their contemporary analyses. Moreover, those wielding power over Australian urban affairs would do well to read it too, lest its lessons be ignored for another generation. 相似文献
77.
环台湾岛海域全日分潮的特征和潮汐、潮流的综合性质 总被引:6,自引:0,他引:6
用97版POC海洋模式,对环台湾岛海域的全日分潮和整个潮汐,潮流综合特征进行三维数值研究。研究海域全日分潮是由太平洋传入的,且来自台湾岛北部海区传入的潮波穿越海峡。由吕宋海峡传入的全日分潮对维持南海的潮运动起着重要作用。全日分潮最大流同时线分布表层有5个圆流点,其中4个本文首次得到。台湾海峡及其以北海区和台湾东部洋区为不规则半日潮区,台湾东南为全日分潮为主的混合潮区。台湾岛北部为气旋式余流涡旋区,环绕台浅滩为反气旋余流涡旋区,澎湖水道开始的转向流预示着海峡及其邻近海区的涨潮流或落潮流的来临。 相似文献
78.
基于“3S”技术,结合水文、地质地貌等野外考察,围绕喀斯特水动力效应、地貌响应及缓冲区的缓冲作用进行分析,探讨了贵南铁路对荔波-环江喀斯特世界自然遗产地地貌价值的影响。结果表明:1)贵南铁路线路穿过荔波-环江喀斯特的缓冲区,未穿过遗产地,对遗产地地貌价值无直接影响;2)线路以桥梁、隧道、路基的形式穿过缓冲区,以桥梁形式跨过遗产地上游地表河与地下河,河中不设桥墩,基本不影响遗产地上游水质水量;缓冲区的九万大山二号隧道可能使缓冲区隧区降深漏斗带内地下水位降低,但对遗产地的水文地质条件和喀斯特作用过程的影响极小;位于缓冲区的路基出露处均为非喀斯特地貌,不影响遗产地喀斯特地貌;3)遗产地大、小七孔与茂兰-环江2个片区分属不同的水文地质单元,无统一的地下水水力联系,贵南铁路对遗产地2个片区之间地下水水力联系及喀斯特作用过程无影响;4)线路将影响缓冲区的13个峰丛洼地共计面积5.32 km2,占缓冲区总面积的1.22%,基本不影响缓冲区的缓冲作用。 相似文献
79.
Fernanda Michalski Jean Paul Metzger Carlos A. Peres 《Global Environmental Change》2010,20(4):705-712
Deforestation in Brazilian Amazonia accounts for a disproportionate global scale fraction of both carbon emissions from biomass burning and biodiversity erosion through habitat loss. Here we use field- and remote-sensing data to examine the effects of private landholding size on the amount and type of forest cover retained within economically active rural properties in an aging southern Amazonian deforestation frontier. Data on both upland and riparian forest cover from a survey of 300 rural properties indicated that 49.4% (SD = 29.0%) of the total forest cover was maintained as of 2007, and that property size is a key regional-scale determinant of patterns of deforestation and land-use change. Small properties (≤150 ha) retained a lower proportion of forest (20.7%, SD = 17.6) than did large properties (>150 ha; 55.6%, SD = 27.2). Generalized linear models showed that property size had a positive effect on remaining areas of both upland and total forest cover. Using a Landsat time-series, the age of first clear-cutting that could be mapped within the boundaries of each property had a negative effect on the proportion of upland, riparian, and total forest cover retained. Based on these data, we show contrasts in land-use strategies between smallholders and largeholders, as well as differences in compliance with legal requirements in relation to minimum forest cover set-asides within private landholdings. This suggests that property size structure must be explicitly considered in landscape-scale conservation planning initiatives guiding agro-pastoral frontier expansion into remaining areas of tropical forest. 相似文献
80.