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Although similar processes and functions have been proposed for privacy regulation and place attachment, little theoretical or empirical work encompasses both constructs. In the present study, a theoretical model relates privacy regulation to place attachment in the home. According to this model, the home setting may either facilitate or inhibit privacy regulation with family. When regulation is facilitated, family functioning and feelings of control should be enhanced, promoting attachments to the home.Questionnaire data from student family apartment residents supported this model. Residents who reported greater ease in regulating privacy with family also reported greater apartment attachment. Analyses suggested that this relationship was mediated by family functioning and feelings of control. Similar relationships were found for three different types of attachment.By bridging across concepts often treated separately, the model supported in this study suggests new directions for theoretical and empirical study, and new applications for housing policy and design.  相似文献   
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The extinction of large herbivores, often keystone species, can dramatically modify plant communities and impose key biotic thresholds that may prevent an ecosystem returning to its previous state and threaten native biodiversity. A potentially innovative, yet controversial, landscape‐based long‐term restoration approach is to replace missing plant‐herbivore interactions with non‐native herbivores. Aldabran giant (Aldabrachelys gigantea) and Madagascan radiated (Astrochelys radiata) tortoises, taxonomically and functionally similar to the extinct Mauritian giant tortoises (Cylindraspis spp.), were introduced to Round Island, Mauritius, in 2007 to control the non‐native plants that were threatening persistence of native species. We monitored the response of the plant community to tortoise grazing for 11 months in enclosures before the tortoises were released and, compared the cost of using tortoises as weeders with the cost of using manual labor. At the end of this period, plant biomass; vegetation height and cover; and adult, seedling, flower, and seed abundance were 3–136 times greater in adjacent control plots than in the tortoise enclosures. After their release, the free‐roaming tortoises grazed on most non‐native plants and significantly reduced vegetation cover, height, and seed production, reflecting findings from the enclosure study. The tortoises generally did not eat native species, although they consumed those native species that increased in abundance following the eradication of mammalian herbivores. Our results suggest that introduced non‐native tortoises are a more cost‐effective approach to control non‐native vegetation than manual weeding. Numerous long‐term outcomes (e.g., change in species composition and soil seed bank) are possible following tortoise releases. Monitoring and adaptive management are needed to ensure that the replacement herbivores promote the recovery of native plants. Estudiando el Potencial para Restaurar Ecosistemas Históricos de Forrajeo con Reemplazos Ecológicos de Tortugas Terrestres  相似文献   
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The improvements made by developing countries in the 1970s in petroleum and mineral agreements with transnational corporations have been well documented, and substantial evidence exists to show that some real gains, in terms of host country control over operations, distribution of economic benefits, better employment and training requirements, etc., have in fact been made. In the case of the energy-related minerals, uranium and coal, however, relatively few contracts between Third World governments and transnational corporations have become public, and it is thus difficult to document whether the same gains made in the case of petroleum or non-fuel minerals have been achieved in relation to these energy resources. This article reviews a number of such recent coal and uranium agreements in developing countries. In overall terms, these agreements do not go as far in providing for the interests of host countries as do those negotiated for petroleum or hard minerals. The reasons for this apparent weakness in developing countries' bargaining power in the case of uranium and coal include the specific nature of the markets for these minerals, the structure of transnational corporations in the industry, and the very secrecy which has kept most of these contracts from public view. In the light of the relatively weak markets expected for export sales of coal and uranium through the remainder of the 1980s, it appears unlikey that developing countries can make significant advances in their negotiations to the extent of achieving terms which are more favourable than those contained in the best of the agreements reviewed in this article. It should, however, be possible for host governments to use the more favourable of the agreements reviewed here as standards for future negotiations. Une solide documentation existe sur les améliorations apportées par les pays en développement dans les années '70 dans le domaine des accords pétroliers et miniers avec les sociétés multinationales et il est maintenant bien etabli que des gains réels ont été acquis en ce qui concerne le contrôle des opérations par le pays hôte, la répartition des bénéfices, une meilleure utilisation de la main-d'oeuvre et les obligations de formation professionnelle. Cependant, dans le cas des minerais énergétiques uranium et charbon, relativement très peu de contrats intervenus entre les gouvernements du Tiers Monde et les sociétés multinationales sont tombés dans le domaine public de sorte qu'il est difficile d'établir si des gains semblables à ceux réalisés dans le cadre du pétrole et des minerais métalliques ont été obtenus. Cet article passe en revue certains des accords intervenus récemment dans les domaines du charbon et de l'uranium dans les pays en développement. En termes généraux, ces accords ne vont pas aussi loin dans la protection des intérêts des pays hôtes que ceux qui ont été négociés pour le pétrole et les minerais. La marge de manoeuvre des pays en développement dans le cadre des négociations d'accords portant sur le charbon et l'uranium est limitée en apparence du fait de la nature particulière des marchés de ces minerais, de la place qu'occupent les sociétés multinationales dans l'industrie minière et du caractère confidentiel qui entoure les transactions et les isole de la vue du grand public. Etant donné les tendances baissières des marchés du charbon et de l'uranium à l'exportation pour le reste de cette décennie, il semble peu probable que les pays en développement puissent réaliser des progrès sensibles dans leurs négociations pour atteindre des conditions plus favorables que celles qui figurent dans les meilleurs accords examinés dans cet article. Cependant, les pays hôtes devraient se prévaloir des accords qui leur sont les plus favorables parmi ceux qui sont passés en revue pour les utiliser comme base de leurs futures négociations et tout au moins pour éviter de signer des accords léonins. Los progresos alcanzados en la década del setenta por los países en desar-rollo en los acuerdos con las compañias transnacionales sobre el desarrollo del petróleo y de los minerales ha sido bien documentado y existe evidencia sustantiva de que ha habido ganancias reales en aspectos tales como control del país sobre las operaciones, distribución de beneficios económicos, mejores condiciones para el empleo y el entrenamiento, etc. Sin embargo, en el caso de minerales energéticos, tales como el uranio y el carbón, pocos contratos han sido hechos públicos y es difícil documentar si se tuvieron similares ganancias como en el caso de minerales no energéticos y petróleo. Este artículo pasa revista a un número de dichos contratos recientes sobre carbón y uranio. En términos generales estos contratos no son tan favorables a los países en desarrollo en comparación con los contratos para petróleo y minerales no energéticos. Las razones para esta aparente debilidad del poder de negociación en el caso del carbón y del uranio se debe, entre otras, a la naturaleza específica del mercado para estos minerales, la estruc-tura de las compañías transnacionales dentro de la indústria y el carácter secreto que ha tenido la mayoría de estos contratos con respecto al público en general. A la luz de la relativa debilidad del mercado para las exportaciones de carbón y uranio que se cree que imperará durante el resto de la década del ochenta, parece poco probable que los países en desarrollo puedan hacer avances significativos en sus negociaciones con el objeto de alcanzar términos que sean más favorables que los que se alcanzaron en el mejor de los contratos revisados en el presente artículo. Debería ser posible, sin embargo, que los gobiernos puedan usar como patrón para futuras negociaciones el contrato mas favorable revisado en este artículo y evitar la firma de acuerdos totalmente desfavorables al pais.  相似文献   
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Much of the biodiversity‐related climate change impacts research has focused on the direct effects to species and ecosystems. Far less attention has been paid to the potential ecological consequences of human efforts to address the effects of climate change, which may equal or exceed the direct effects of climate change on biodiversity. One of the most significant human responses is likely to be mediated through changes in the agricultural utility of land. As farmers adapt their practices to changing climates, they may increase pressure on some areas that are important to conserve (conservation lands) whereas lessening it on others. We quantified how the agricultural utility of South African conservation lands may be altered by climate change. We assumed that the probability of an area being farmed is linked to the economic benefits of doing so, using land productivity values to represent production benefit and topographic ruggedness as a proxy for costs associated with mechanical workability. We computed current and future values of maize and wheat production in key conservation lands using the DSSAT4.5 model and 36 crop‐climate response scenarios. Most conservation lands had, and were predicted to continue to have, low agricultural utility because of their location in rugged terrain. However, several areas were predicted to maintain or gain high agricultural utility and may therefore be at risk of near‐term or future conversion to cropland. Conversely, some areas were predicted to decrease in agricultural utility and may therefore prove easier to protect from conversion. Our study provides an approximate but readily transferable method for incorporating potential human responses to climate change into conservation planning. Uso de Cambios en la Utilidad Agrícola para Cuantificar Riesgos Futuros para la Conservación Inducidos por el Clima  相似文献   
38.
Habitat loss is the principal threat to species. How much habitat remains—and how quickly it is shrinking—are implicitly included in the way the International Union for Conservation of Nature determines a species’ risk of extinction. Many endangered species have habitats that are also fragmented to different extents. Thus, ideally, fragmentation should be quantified in a standard way in risk assessments. Although mapping fragmentation from satellite imagery is easy, efficient techniques for relating maps of remaining habitat to extinction risk are few. Purely spatial metrics from landscape ecology are hard to interpret and do not address extinction directly. Spatially explicit metapopulation models link fragmentation to extinction risk, but standard models work only at small scales. Counterintuitively, these models predict that a species in a large, contiguous habitat will fare worse than one in 2 tiny patches. This occurs because although the species in the large, contiguous habitat has a low probability of extinction, recolonization cannot occur if there are no other patches to provide colonists for a rescue effect. For 4 ecologically comparable bird species of the North Central American highland forests, we devised metapopulation models with area‐weighted self‐colonization terms; this reflected repopulation of a patch from a remnant of individuals that survived an adverse event. Use of this term gives extra weight to a patch in its own rescue effect. Species assigned least risk status were comparable in long‐term extinction risk with those ranked as threatened. This finding suggests that fragmentation has had a substantial negative effect on them that is not accounted for in their Red List category. Estimación del Riesgo de Extinción Mediante Modelos Metapoblacionales de Fragmentación a Gran Escala  相似文献   
39.
Abstract: Chytridiomycosis is linked to the worldwide decline of amphibians, yet little is known about the demographic effects of the disease. We collected capture–recapture data on three populations of boreal toads (Bufo boreas [Bufo = Anaxyrus]) in the Rocky Mountains (U.S.A.). Two of the populations were infected with chytridiomycosis and one was not. We examined the effect of the presence of amphibian chytrid fungus (Batrachochytrium dendrobatidis [Bd]; the agent of chytridiomycosis) on survival probability and population growth rate. Toads that were infected with Bd had lower average annual survival probability than uninfected individuals at sites where Bd was detected, which suggests chytridiomycosis may reduce survival by 31–42% in wild boreal toads. Toads that were negative for Bd at infected sites had survival probabilities comparable to toads at the uninfected site. Evidence that environmental covariates (particularly cold temperatures during the breeding season) influenced toad survival was weak. The number of individuals in diseased populations declined by 5–7%/year over the 6 years of the study, whereas the uninfected population had comparatively stable population growth. Our data suggest that the presence of Bd in these toad populations is not causing rapid population declines. Rather, chytridiomycosis appears to be functioning as a low‐level, chronic disease whereby some infected individuals survive but the overall population effects are still negative. Our results show that some amphibian populations may be coexisting with Bd and highlight the importance of quantitative assessments of survival in diseased animal populations.  相似文献   
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Two studies examined whether the previously documented coping strategy of social withdrawal in response to chronic crowding is related to changes in social information processing. In both studies we found evidence that individuals residing in crowded homes in comparison to uncrowded homes were less cognizant of personal information about strangers in an incidental encounter under naturalistic, uncrowded conditions as well as under highly crowded conditions, occurring in the laboratory. Furthermore, we show in the experimental study that interference with this social withdrawal process has significant effects on social information processing. In study 2 we also demonstrate that social withdrawal in response to acute crowding is an effective coping strategy for reducing short-term stress for those who have learned to employ this strategy while living under chronically crowded conditions. All of these results occur independently of income levels.  相似文献   
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