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21.
Deforestation and associated ecological disturbances are the issues of global concern.Researchers have investigated a number of driving forces which accelerate the rate of deforestation at local and regional levels.These include poverty,population growth,market demand and prices,political instability,agricultural expansion and changes in property right and ownership regimes.This paper seeks to explore the impacts of population growth,changing tenure system and other socioeconomic factors on the forest cover of Roghani Valley,located in Hindu Raj Mountains,Northern Pakistan.The present study is mainly based on information collected through participatory observation,selfadministered interviews and questionnaire survey.Geographical Information System(GIS) database is also used for mapping and quantification.The results reveal that in the past three to four decades the study area has been subjected to severe deforestation and about half of the forest area has been converted into barren land.Thus,the area under natural forests decreased from 2099 to 1444 hectares in four decades.This large-scale deforestation is attributed to both proximate and under lying causes particularly traditional land tenure system and demographic development.Consequently,forest resources have been degraded and a number of plant species have disappeared from the forests of the study area while several others are in the process of disappearance.  相似文献   
22.
Abstract

Tenure security is commonly recognized as an important factor in stimulating long-term investments in land. Recent studies suggest that a distinction between legal, actual and perceived tenure security needs to be made in analyzing tenure security. This study discusses the relationships between legal, actual and perceived land tenure security in rural China, and empirically examines the impact of actual on perceived land tenure security by applying Probit models to household and village survey data collected in four provinces. Using household expectations about the absence of land reallocations within the next five years as the dependent variable, we find that tenure security is positively affected by the possession of land certificates in villages that periodically reallocated land but not in villages that did not do so. The estimated impact is larger for land certificates issued in the new round of land certification than for land certificates that were issued earlier.  相似文献   
23.
《Urban geography》2013,34(2):211-235
This study examines the changing demography of the Spanish city of León, and aims to explore the manner in which its urban fabric was reshaped by processes of reurbanization, a dynamic whereby the inner city becomes more attractive to a wide variety of household types and social groups. We draw on sociodemographic analyses of municipal census data, as well as a customized questionnaire survey of local residents. Empirical evidence is provided both for the city as a whole and two inner-city districts, Casco Antiguo and El Ejido. Among other findings, it is argued that, although the contiguous built-up area of the city is clearly losing its inhabitants through out-migration and aging, there are a series of small-scale migration flows that increasingly concentrate "nontraditional" households in and around the city center. This is accompanied by an increasing trend toward "city-mindedness" as a residential choice and housing preference among both in-migrants and the long-time residential population. Overall, the evidence points to the emergence of a spatially fragile, fragmented reurbanization process.  相似文献   
24.
SOFTWARE REVIEWS     
ATLAS*GIS , Version 1.0. ATLAS*MapMaker , Version 4.0. FIVFIV-SINSIN , Release 9.0. Geo-EAS , Version 1.2.1. Evan Englund Sim City , Version 1.0 Statistix , Version 3.1.  相似文献   
25.
26.
The period 1996-2001 has witnessed a refocusing of population growth on Sydney and Melbourne as both cities have developed significant concentrations of so-called 'new economy' jobs and taken on, to greater or lesser extents, the characteristics of global cities. The consequence of these trends, for Sydney most particularly, is population growth. This paper establishes this demographic reality by describing recent demographic trends in Sydney and possible future scenarios for Sydney's population, given differing levels of fertility, internal migration and international migration. A related future trend is also traced--that the number of households in Sydney will grow more rapidly than the population due to changes in household structure. This raises the issue of how and where these households will be accommodated, given the relative land shortage in the Sydney Statistical Division and given that there is no doubt that planners in New South Wales will be attempting to maintain and enhance Sydney's status as a global city. In sum, the paper argues that Sydney planners should be preparing for growth of around one million people in the next 20 years and a further one million in the following 30 years. To maintain that potential future residents of Sydney can be redirected to other parts of New South Wales is a vain hope.  相似文献   
27.
Derek R. Hall 《GeoJournal》1998,46(3):283-287
This paper examines the prospects for Albanian rural diversification with particular reference to rural tourism. In the early 1990s, tourism was identified by the Albanian government and Western development consultants as a likely vehicle for an appropriate and sustainable development strategy, given the relative wealth generated by international tourism in neighbouring Greece, Italy and Croatia. Pressure has been exerted by commercial developers for mass coastal tourism and permission for around 40 new tourist development has been granted. But Albania embraces a considerable wealth of natural and cultural heritage, which provides opportunities for the development of small scale rural tourism carefully integrated into the local economy with respect to organic farming, quality wine production and sustainable fishing. But sensitive social integration is vital where it is difficult to identify rural communities where there is a conspicuous absence of local consensus. The resurgence of traditional social systems and the empowerment of local actors in cases where organised crime has taken root pose major problems for rural diversification. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
28.
Assessing the environmental impact due to consumption of goods and services is a pivotal step towards achieving the sustainable development goal related to responsible production and consumption (i.e. SDG 12). Household appliances plays a crucial role and should be assessed in a systemic manner, namely considering all life cycle stages, technological efficiency, and affluence aspects. The present study assess the impact of such household appliances used in Europe, and tests scenarios of potential impact reduction at various scales. Life cycle assessment is applied to 14 different household appliances (ranging from dishwashers to television devices) selected to build a set of representative products, based on their economic value and diffusion in households in Europe. Related impacts are calculated with the Environmental Footprint method for calculating a Consumer Footprint “appliances” for the baseline year 2010. A number of scenarios encompassing eco-solutions on a technical level, changes in consumption pattern, behavioral changes, as well as the combination of all these aspects are run to estimate the Consumer Footprint related to household appliances for the year 2030, compared against this baseline scenario. The baseline Consumer Footprint is confirming the importance of the use phase in leading the impacts in almost all impact categories. Testing different scenarios concludes that there is a reduction of the impact for most of the categories (with up to 67% for the ozone depletion potential, and still around 35% for the global warming potential), while two of the here examined impact categories (i.e. land-use and mineral resource depletion) show an overall potential that is even negative – i.e. the results of all scenarios are higher than the ones of the 2010 baseline scenario. The increase in purchase and use of such appliances may offset energy efficiency benefits in some of the examined categories. Hence, the assessment of sustainability of appliances consumption should always include several scales, from the efficiency of the products (micro scale), to the improvement of the energy mix (meso scale), up to accounting for socio-economic drivers and patterns of consumption affecting the overall appliances stock (macro scale).  相似文献   
29.
Two distinct, conflicting, land-use planning paradigms affect drylands: one seeking environmentally sustainable outcomes and one addressing political-demographic concerns. The environmental paradigm is relatively new and is couched in the lexicon of sustainable development, combating desertification and biodiversity conservation. These concerns proscribe planning principles that allow for human settlement in drylands while minimizing its environmental impact. The latter paradigm has a longer history, born in central governments’ desire to secure sovereignty over outlying regions. These concerns result in planning goals that conflict with environmental goals. The environmental paradigm encourages compact development and efficient land-use, while the political-demographic one encourages in-migration of ‘friendly’ populations and the establishment of a physical presence on a maximum amount of land. Using Israel’s Negev Desert and China’s Xinjiang region as case studies, we suggest that successful implementation of sustainable dryland management depends on recognizing the challenge presented by political-demographic planning motivations. As such, successful implementation of environmental planning requires resolution of existing political conflicts. Since drylands are characteristically geographic and demographic frontiers, they are ideal settings in which to study the conflict between environmental and political-demographic goals and they provide an opportunity to better understand how this conflict creates a barrier to sustainable development.  相似文献   
30.
Gorgonians are important structuring species of the Mediterranean hard‐bottom communities that are threatened by disturbances such as increasing seawater temperature, mucilaginous events and destructive fishing, among others. In this study we assessed for the first time the population structure and conservation status of one of the most common gorgonians in the Eastern Adriatic Sea, the red gorgonian Paramuricea clavata. During late spring 2009, nine populations dwelling between 30 and 50 m depth were examined by SCUBA diving along 200 km of the Croatian coastline. The density ranged between 7 and 20 colonies·m?2. The mean and maximum colony heights were 31.2 ± 22.7 cm (±SD) and 138 cm, respectively. Two main patterns of P. clavata size frequency distributions were observed: the first one with a higher proportion of juveniles (~30%) observed mostly in the northernmost populations, and the second one with a higher proportion of larger colonies (>25% of colonies >40 cm in height). Regarding the disturbance impact level, the proportion of healthy colonies (with <10% of injured surface) was high in almost all of the studied populations (>60%) and the mean extent of injury (i.e. denuded axis or epibiosis) was 9.7 ± 4% (±SD), indicating low impacts. Contrasting population size structures with high recruitment in mature populations provides new insights into the demographic structure of the Mediterranean gorgonian forests dwelling in their upper bathymetric range (<50 m depth). Furthermore, these size structures and the low impact levels suggest a current favorable conservation status of the studied populations in the Eastern Adriatic Sea and provide a baseline for their monitoring in the future.  相似文献   
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