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321.
Abstract: Rare or narrowly distributed species may be threatened by stressors to which they have never been exposed or for which data are very limited. In such cases the species response cannot be predicted on the basis of directly measured data, but may be inferred from the response of one or more appropriate surrogate species. Here, I propose a practical way to use the stressor response of one or more surrogate species to develop a working hypothesis or model of the stressor response of the target species. The process has 4 steps: (1) identify one or more candidate surrogate species, (2) model the relationship between the stressor and the response variable of interest for the surrogate species, (3) adapt the stressor–response relationship from the surrogate species to a model for the target species, possibly using Bayesian methods, and (4) incorporate additional data as they become available and adjust the response model of the target species appropriately. I applied the approach to an endangered fish species, the amber darter (Percina antesella), which is potentially threatened by urbanization. I used a Bayesian approach to combine data from a surrogate species (the bronze darter[Percina palmaris]) with available data for the amber darter to produce a model of expected amber darter response. Although this approach requires difficult decisions on the part of the manager, especially in the selection of surrogate species, its value lies in the fact that all assumptions are clearly stated in the form of hypotheses, which may be scrutinized and tested. It therefore provides a rational basis for instituting management policy even in the face of considerable uncertainty.  相似文献   
322.
Blood level of calcium fractions (ionized and bound), phosphates, magnesium and albumin were measured in non‐insulin dependent diabetic patients (NIDD). Results were compared with healthy controls to elucidate the pathogenesis of probable changes of these elements. Total ionized calcium and magnesium showed significant decrease (p<0.001, p<0.05 and p<0.05) respectively. Phosphates showed non‐significant decrease while albumin reported nearly similar results. Positive correlation between inorganic phosphates and ionized calcium (r = 0.48, p<0.05) was observed only in healthy control group, not in diabetics. This may be attributed to alteration of ions excretions under diabetic condition through unknown mechanism. Additive increase of heparin sodium units in vitro to normal blood resulted in progressive fall in ionized calcium. Significant decrease was only observed upon addition of higher unit (5IU/ml). This must be taken into consideration biochemically for plasma determination of ionized calcium.  相似文献   
323.
Location matters for the value of capital assets. The value of changes in natural capital wealth can depend on whether natural capital asset prices are measured locally and then aggregated or whether average values are applied over aggregate representative areas. Spatial heterogeneity of resource characteristics and institutions impact approximations of the intertemporal welfare function and accounting price function because when spatial aggregation precedes valuation it implies greater arbitrage opportunities leading to more inelastic shadow (accounting) price functions than when valuation is done locally and then aggregated. Aggregation of observed values across varying resource and institutional characteristics can lead to omitted variables bias. We illustrate these results in the context of groundwater in the Kansas High Plains Aquifer and demonstrate that the accounting price function is less elastic when the accounting price is measured locally. Failure to measure locally and then aggregate could lead to undervaluing scarce resources and overvaluing plentiful ones, which biases wealth accounts in favor of passing the non-declining wealth sustainability test.  相似文献   
324.
Participatory epidemiology methods were employed retrospectively in three pastoralist regions of Ethiopia to estimate the specific causes of excess livestock mortality during drought. The results showed that starvation/dehydration accounted for between 61.5 and 100 per cent of excess livestock mortality during drought, whereas disease‐related mortality accounted for between 0 and 28.1 per cent of excess mortality. Field observations indicate that, in livestock, disease risks and mortality increase in the immediate post‐drought period, during rain. The design of livelihoods‐based drought response programmes should include protection of core livestock assets, and it should take account of the specific causes of excess livestock mortality during drought and immediately afterwards. This study shows that, when comparing livestock feed supplementation and veterinary support, relatively more aid should be directed at the former if the objective is to protect core livestock during drought. Veterinary support should consider disease‐related mortality in the immediate post‐drought period, and tailor inputs accordingly.  相似文献   
325.
Jacques Henry 《Disasters》2013,37(2):293-316
This paper proposes an inductive analysis of the decision as to whether to return or to relocate by persons in the State of Louisiana, United States, who evacuated after Hurricanes Katrina and Rita in August and September 2005, respectively. Drawing on interviews with evacuees in these events and extensive fieldwork in the impacted area, the paper seeks to identify the folk dimensions of the decision‐making process, assess their arrangements, and situate the process in the larger context of risk and resilience in an advanced society. It suggests that, despite the material and emotional upheaval experienced by affected persons, the decision‐making process is a rational endeavour combining a definite set of tightly interconnected factors, involving material dimensions and substantive values that can act in concert or in conflict. In addition, it indicates that there are significant variations by geographic areas, homeownership, and kind of decision. Some theoretical implications, practical measures, and suggestions for future research are examined.  相似文献   
326.
The ever-increasing complexity of disasters demands utilisation of knowledge that exists outside domains traditionally drawn upon in disaster management. To be operationally useful, such knowledge must he extracted, combined with information generated by the disaster itself, and transformed into actionable knowledge. The process, though, is hampered by existing, business-oriented approaches to knowledge management, by technical issues related to access to relevant, multi-domain information/knowledge, and by executive decision-making processes based predominantly on historical knowledge. Consequently, as shown by many recent incidents, the management of large-scale (mega) disasters is often inefficient and exceedingly costly. This paper demonstrates that the integration of modified information and knowledge management into the concepts of network-centric operations and network-enabled capabilities, and the employment of Boyd's OODA (Observe, Orient, Decide, and Act) Loop-based decision-making in unpredictable and dynamically changing environments, may address some of these problems.  相似文献   
327.
Fan Li  Tao Zhou  Lin Wang 《Disasters》2021,45(1):180-201
This study performed a comparative analysis of changes in the operating status of initial surviving disaster‐stricken businesses and non‐disaster‐stricken businesses in Lushan County, China, after a devastating earthquake on 20 April 2013. It used a logistic regression model to explore the key factors associated with ‘post‐disaster continued business operation’ in the long term. Field data were collected from 1,078 businesses and questionnaire data from 263 small businesses between 2013 and 2017. The results indicate that a higher proportion of initial surviving disaster‐stricken businesses than non‐disaster‐stricken businesses managed to remain operational in each observation period. The continued operation of disaster‐stricken businesses after the earthquake was positively associated with the owner's age, previous disaster experience, pre‐disaster financial conditions, closure duration, and borrowing money from family or friends. A negative association was found with the size of the business. The findings serve as a vital reference for strategies to promote post‐disaster continued business operation.  相似文献   
328.
Abstract. Hyetographs are essential to many hydrological designs. Many studies have shown that hyetographs are specific to storm types and durations. Recent work presented evidence that dimensionless hyetographs are scale invariant. We show that the simple scaling property of rainfall guarantees that the normalized rainfall rates of different storm durations are identically distributed and propose a nonstationary Gauss‐Markov model based on the annual maximum events that arise from the dominant storm type. We derive the unique estimators for the parameters of the Gauss‐Markov model under two constraints that: (a) the typical peak rainfall rate is preserved, and (b) the most likely hyetograph is obtained. One attractive feature of this model is that it allows translating hyetographs between storms of different durations. Two examples illustrate our model.  相似文献   
329.
The dominant paradigm in disaster risk reduction (DRR) policies has been seriously contested because of its reliance on interventions based on technocratic expertise. In the Mexican context, the influence of informal practices such as clientelism and cartelisation of the political system produces environmental degradation and vulnerability to disasters within the communities in the study site. This paper contributes to understanding of failed institutional processes and parallel practices that intensify vulnerability to disasters by contrasting the discourses of agents within a peri‐urban community in central Mexico. Employing the Situational Analysis Approach as a methodological framework, the study identifies divergent views and practices within the community, leading to different responses to disasters and to different perceptions regarding institutional performance. In addition, it finds that institutional decision‐making, based only on scientific and technical expertise, has resulted in unintended consequences that influence ongoing vulnerability to floods in the site under review.  相似文献   
330.
Peter M. Lawther 《Disasters》2016,40(3):494-517
Contemporary responses to facilitate long‐term recovery from large‐scale natural disasters juxtapose between those of humanitarian agencies and governments and those of the affected community. The extent to which these mechanisms articulate is crucial to the recovery propensity of the affected communities. This research examines such action by exploring the relationship between the scale of post‐disaster response interventions, the extent of community participation in them, and their impact on community recovery, using a community wealth capital framework. The investigation was applied to a study of the longer‐term community recovery of the island of Vilufushi, Republic of Maldives, which was almost completely destroyed by the Indian Ocean tsunami of 26 December 2004. Data were analysed through the employment of a pattern match technique and a holistic recovery network analysis. The research framework, informed by the case‐study results, other long‐term recovery evaluations, and existing resilience theory, is reconfigured as a testable roadmap for future post‐disaster interventions.  相似文献   
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