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71.
Systematic conservation planning is intended to inform spatially explicit decision making. Doing so requires that it be integrated into complex regulatory and governance processes, and there are limited instances where this has been achieved effectively. South Africa is a global leader in the application of conservation plans, the outputs of which are widely used for spatial planning and decision making in many spheres of government. We aimed to determine how conservation planning in the country progressed from theory to implementation, and to identify practical actions that enabled this transition, by assessing temporal trends in the characteristics of conservation plans (1990–2017, n = 94). Since 2010 conservation planning has entered an operational period characterized by government leadership of plans, administrative rather than ecological planning domains, decreasing size of planning units, increasing emphasis on end-user products, and scheduled revision of plans. Key actions that enabled this progression include transitioning leadership of plans from scientists to practitioners, building capacity within implementing agencies, creating opportunities to integrate plans in legislative processes, establishing a strong community of practice, adopting implementation-focused methods, and balancing standardization with innovation. Learning from this model will allow other countries, particularly those with a similar megadiverse, developing context, to operationalize conservation planning into spatial planning and decision making.  相似文献   
72.
All frogs are assumed to jump in a similar manner by rapidly extending hindlimbs during the propulsive phase and rotating the limbs forward during flight in order to land forelimbs first. However, studies of jumping behavior are lacking in the most primitive living frogs of the family Leiopelmatidae. These semi-aquatic or terrestrial anurans retain a suite of plesiomorphic morphological features and are unique in using an asynchronous (trot-like) rather than synchronous “frog-kick” swimming gait of other frogs. We compared jumping behavior in leiopelmatids to more derived frogs and found that leiopelmatids maintain extended hindlimbs throughout flight and landing phases and do not land on adducted forelimbs. These “belly-flop” landings limit the ability for repeated jumps and are consistent with a riparian origin of jumping in frogs. The unique behavior of leiopelmatids shows that frogs evolved jumping before they perfected landing. Moreover, an inability to rapidly cycle the limbs may provide a functional explanation for the absence of synchronous swimming in leiopelmatids.  相似文献   
73.
Predicted climate warming is expected to have profound effects on bark beetle population dynamics in the southwestern United States. Temperature-mediated effects may include increases in developmental rates, generations per year, and changes in habitat suitability. As a result, the impacts of Dendroctonus frontalis and Dendroctonus mexicanus on forest resources are likely subject to amplification. To assess the implications of such change, we evaluated the generations per year of these species under three climate scenarios using a degree-day development model. We also assessed economic impacts of increased beetle outbreaks in terms of the costs of application of preventative silvicultural treatments and potential economic revenues forgone. Across the southwestern USA, the potential number of beetle generations per year ranged from 1–3+ under historical climate, an increase of 2–4+ under the minimal warming scenario and 3–5+ under the greatest warming scenario. Economic benefits of applying basal area reduction treatments to reduce forest susceptibility to beetle outbreaks ranged from 7.75/ha (NM) to7.75/ha (NM) to 95.69/ha (AZ) under historical conditions, and 47.96/ha (NM) to47.96/ha (NM) to 174.58/ha (AZ) under simulated severe drought conditions. Basal area reduction treatments that reduce forest susceptibility to beetle outbreak result in higher net present values than no action scenarios. Coupled with other deleterious consequences associated with beetle outbreaks, such as increased wildfires, the results suggest that forest thinning treatments play a useful role in a period of climate warming.  相似文献   
74.
Hunt B  Vincent AC 《Ambio》2006,35(2):57-64
Collecting marine organisms for the discovery and development of pharmaceuticals has been perceived variously as sustaining and threatening conservation. Our initial expectations that marine bioprospecting might pose conservation challenges were largely not confirmed. Thousands of marine species have been collected for initial assessment, but usually only in very small amounts. Very few compounds are sufficiently promising to provoke re-collections, where volumes can be much larger. This is where conservation concerns may arise, particularly if the organism is rare, has a restricted distribution, or is targeted in one narrow area. However, industry generally seeks to avoid dependency on small populations, for economic as well as ecological reasons. Alternative supply strategies to wild capture include synthesis and culture. Mandatory collection protocols and environmental impact (stock) assessments are useful routes for management to achieve sustainable use where extraction is desirable. In general, the scanty information available suggests that marine bioprospecting for pharmaceuticals may have minimal impacts on the environment, particularly compared with those created by other pressures.  相似文献   
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ABSTRACT: For more than 30 years, a program of continuous monitoring of pH, acidity, alkalinity, and other parameters has been maintained on a network of large streams degraded by acid mine drainage in the northern Appalachian high sulfur coal region. Continuous records since 1952 are available at a number of stations, and at several stations, acidity records date back to 1930. Comparable analysis techniques were maintained over the period of record, assuring the long term continuity of the database. This monitoring program has captured integrated long term trends within large and complex watersheds with numerous and varied types of mine discharges. The focus of this paper is a historical trend analysis of lightly to severely acid degraded major tributaries of the Allegheny River. Over the past three decades, all of the Allegheny River drainage basin stations have demonstrated steady and substantial declines in acidity and associated increases in pH and alkalinity. The average recorded decline in total acidity at four stations monitored since the 1950s was 94 percent. Since the 1970s, acidity declined by an average of 63 percent at 10 stations. Oxidative exhaustion of pyritic minerals exposed by mining is proposed as a major factor influencing these trends.  相似文献   
78.
This study examined the predictive contribution of occupational and marital stress to the development of symptomatolgoy, affective disorder, and alcohol-related problems in a sample of 325 male power plant employees interviewed at baseline and one-year follow up. After controlling for known clinical and social risk factors, we found statistically significant predictive effects of job demands on affective disorder and job decision latitude on alcohol problems. In addition, the specific combination of high job demands with low decision latitude was important in predicting the occurrence of alcohol problems. Marital stress was not predictive of poorer mental health. The analyses provided only minimal support for a stress-buffering rote of social support.  相似文献   
79.
Pesticide applications to agricultural lands in California, USA, are reported to a central data base, while data on water and sediment quality are collected by a number of monitoring programs. Data from both sources are geo-referenced, allowing spatial analysis of relationships between pesticide application rates and the chemical and biological condition of water bodies. This study collected data from 12 watersheds, selected to represent a range of pesticide usage. Water quality parameters were measured during six surveys of stream sites receiving runoff from the selected watershed areas. This study had three objectives: to evaluate the usefulness of pesticide application data in selecting regional monitoring sites, to provide information for generating and testing hypotheses about pesticide fate and effects, and to determine whether in-stream nitrate concentration was a useful surrogate indicator for regional monitoring of toxic substances. Significant correlations were observed between pesticide application rates and in-stream pesticide concentrations (p < 0.05) and toxicity (p < 0.10). In-stream nitrate concentrations were not significantly correlated with either the amount of pesticides applied, in-stream pesticide concentrations, or in-stream toxicity (all p > 0.30). Neither total watershed area nor the area in which pesticide usage was reported correlated significantly with the amount of pesticides applied, in-stream pesticide concentrations, or in-stream toxicity (all p > 0.14). In-stream pesticide concentrations and effects were more closely related to the intensity of pesticide use than to the area under cultivation.  相似文献   
80.
In 2009, the Sustainable Remediation Forum released a white paper entitled “Integrating sustainable principles, practices, and metrics into remediation projects” (Ellis & Hadley, 2009, Remediation, 19, pp. 5–114). Sustainable remediation was a relatively new concept, and the white paper explored a range of approaches on how sustainability could be integrated into traditional remediation projects. This paper revisits the 2009 white paper, providing an overview of the early days of the evolving sustainable remediation practice and an assessment of the progress of sustainable remediation over the last 10 years with a primary focus on the United States. The current state of the sustainable remediation practice includes published literature, current practices and resources, applications, room for improvement, international progress, the virtuous cycle that applying sustainable remediation creates, and the status of the objectives cited in the 2009 white paper. Over the last decade, several sustainable remediation frontiers have emerged that will likely be a focus in advancing the practice. These frontiers include climate change and resiliency, weighting and valuation to help better consolidate different sustainable remediation metrics, programmatic implementation, and better integration of the societal impacts of sustainable remediation. Finally, as was the case for the 2009 white paper, this paper explores how sustainable remediation may evolve over the next 10 years and focuses on the events and drivers that can be significant in the pace of further development of the practice. The events and drivers include transformation impacts, societal influences, and the continued development of new technologies, approaches, and tools by remediation practitioners. The remediation industry has made significant progress in developing the practice of sustainable remediation and has implemented it successfully into hundreds of projects. While progress has been significant, an opportunity exists to implement the tenets of sustainable remediation on many more projects and explore new frontiers to help improve the communication, integration, and derived benefits from implementing sustainable remediation into future remediation projects.  相似文献   
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