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131.
Environmental Science and Pollution Research - A novel adsorbent (PN-Fe3O4-IDA-Zr) was developed from the chemical modification of peanut husk (a low cost material) with Fe3O4, iminodiacetic acid...  相似文献   
132.
Environmental Chemistry Letters - The rising pollution of water resources is threatening the health of humans and ecosystems, calling for advanced methods to clean polluted waters. Adsorption on...  相似文献   
133.
Analytic webs support the synthesis of ecological data sets   总被引:1,自引:0,他引:1  
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134.
The conservation of wildlife requires management based on quantitative evidence, and especially for large carnivores, unraveling cause‐specific mortalities and understanding their impact on population dynamics is crucial. Acquiring this knowledge is challenging because it is difficult to obtain robust long‐term data sets on endangered populations and, usually, data are collected through diverse sampling strategies. Integrated population models (IPMs) offer a way to integrate data generated through different processes. However, IPMs are female‐based models that cannot account for mate availability, and this feature limits their applicability to monogamous species only. We extended classical IPMs to a two‐sex framework that allows investigation of population dynamics and quantification of cause‐specific mortality rates in nonmonogamous species. We illustrated our approach by simultaneously modeling different types of data from a reintroduced, unhunted brown bear (Ursus arctos) population living in an area with a dense human population. In a population mainly driven by adult survival, we estimated that on average 11% of cubs and 61% of adults died from human‐related causes. Although the population is currently not at risk, adult survival and thus population dynamics are driven by anthropogenic mortality. Given the recent increase of human‐bear conflicts in the area, removal of individuals for management purposes and through poaching may increase, reversing the positive population growth rate. Our approach can be generalized to other species affected by cause‐specific mortality and will be useful to inform conservation decisions for other nonmonogamous species, such as most large carnivores, for which data are scarce and diverse and thus data integration is highly desirable.  相似文献   
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Mittelstet, Aaron R., Michael D. Smolen, Garey A. Fox, and Damian C. Adams, 2011. Comparison of Aquifer Sustainability Under Groundwater Administrations in Oklahoma and Texas. Journal of the American Water Resources Association (JAWRA) 1‐8. DOI: 10.1111/j.1752‐1688.2011.00524.x Abstract: We compared two approaches to administration of groundwater law on a hydrologic model of the North Canadian River, an alluvial aquifer in northwestern Oklahoma. Oklahoma limits pumping rates to retain 50% aquifer saturated thickness after 20 years of groundwater use. The Texas Panhandle Groundwater Conservation District’s (GCD) rules limit pumping to a rate that consumes no more than 50% of saturated thickness in 50 years, with reevaluation and readjustment of permits every 5 years. Using a hydrologic model (MODFLOW), we simulated river‐groundwater interaction and aquifer dynamics under increasing levels of “development” (i.e., increasing groundwater withdrawals). Oklahoma’s approach initially would limit groundwater extraction more than the GCD approach, but the GCD approach would be more protective in the long run. Under Oklahoma rules more than half of aquifer storage would be depleted when development reaches 65%. Reevaluation of permits under the Texas Panhandle GCD approach would severely limit pumping as the 50% level is approached. Both Oklahoma and Texas Panhandle GCD approaches would deplete alluvial base flow at approximately 10% development. Results suggest periodic review of permits could protect aquifer storage and river base flow. Modeling total aquifer storage is more sensitive to recharge rate and aquifer hydraulic conductivity than to specific yield, while river leakage is most sensitive to aquifer hydraulic conductivity followed by specific yield.  相似文献   
137.
We investigated the hypothesis that perception of psychological restorativeness during visits to coastal parks is modified by objective and perceived environmental conditions. Visitors (n = 1153) to California beaches completed a survey on perceived weather, environmental quality, and perceived restorativeness. We used generalized ordinal logistic models to estimate the association between environmental parameters and odds of perceiving higher levels of restorativeness. Visitors perceived greater restorativeness at beaches when ambient temperatures were at or below mean monthly temperatures and during low tides. The odds of perceiving the environment as more psychologically restorative were three times greater when visiting on days defined by government policy as having good air quality (OR = 3.25; CI: 1.69–6.28). Visitors’ perception of air (OR = 1.56; CI: 1.14–2.18) and water quality (OR = 1.78; CI: 1.28–2.49) also affected perceived restorativeness; with perceived healthy days more restorative. Warmer temperatures with less space due to sea level rise and poor environmental quality will restrict restorative experiences in recreational facilities designed for urban populations.  相似文献   
138.
ABSTRACT: In this paper we seek to identify historical indicators of international freshwater conflict and cooperation and to create a framework to identify and evaluate international river basins at potential risk for future conflict. We derived biophysical, socioeco‐nomic, and geopolitical variables at multiple spatial and temporal scales from GIS datasets of international basins and associated countries, and we tested these variables against a database of historical incidents of international water related cooperation and conflict from 1948 to 1999. International relations over freshwater resources were overwhelmingly cooperative and covered a wide range of issues, including water quantity, water quality, joint management, and hydropower. Conflictive relations tended to center on quantity and infrastructure. No single indicator—including climate, water stress, government type, and dependence on water for agriculture or energy—explained conflict/cooperation over water. Even indicators showing a significant correlation with water conflict, such as high population density, low per capita GDP, and overall unfriendly international relations, explained only a small percentage of data variability. The most promising sets of indicators for water conflict were those associated with rapid or extreme physical or institutional change within a basin (e.g., large dams or internationalization of a basin) and the key role of institutional mechanisms, such as freshwater treaties, in mitigating such conflict.  相似文献   
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How does transboundary water cooperation begin at the initial stages, and how can third parties help to foster said cooperation? Many nations with transboundary waters do not cooperate or have ceased cooperation. Yet cooperation often prevails, resulting in 688 water‐related treaties signed from 1820 to 2007. We address the following: by which practices can development partners best design and implement cooperative projects at the state level to enhance basin water security in the earliest stages? This article identifies strategies for initiating cooperation and lessons drawn from reviewing select cases. We compiled from the Oregon State University Transboundary Freshwater Dispute Database all transboundary water resources projects over the last decade with multinational participation. We selected 10 case studies that enhance water security that fit the following filtering criteria: (1) Funding exclusively/primarily from outside sources, (2) Including nonofficial stakeholders in project design/implementation, (3) Absence of formal relations around water resources between or among the riparian nations before the project was discussed, (4) Project design possibly enhancing hydropolitical relations. Findings suggest that to enhance water security, project designs should respect participating riparians' autonomies, create basin‐wide networks of scientists, allow for each partner to garner responsibility for project activities, and consult a diverse group of stakeholders.  相似文献   
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