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41.
Zhang J  Liu SS  Dou RN  Liu HL  Zhang J 《Chemosphere》2011,82(7):1024-1029
Ionic liquids (ILs) are a fascinating group of new chemicals with the potential to replace the classical volatile organic solvents, stimulating many applications in chemical industry. In case ILs are released to the environment, possible combined toxicity should be taken into account and it is, however, often neglected up to now. In this paper, therefore, the concentration-response curves (CRCs) of four groups of IL mixtures with various mixture ratios to Vibrio qinghaiensis sp.-Q67 were determined using the microplate toxicity analysis and were compared to the CRCs predicted by an additive reference model, the concentration addition (CA) or independent action (IA), to identify the toxicity interaction. It is showed that most of the IL mixture rays displayed the classical addition while the remaining rays exhibited antagonism or synergism. Moreover, it is found that the pEC50 values of the mixture rays exhibiting antagonism or synergism are well correlated with the mixture ratio of a certain IL therein.  相似文献   
42.
Corruption is a threat to the purpose of humanitarian assistance. Until fairly recently, humanitarian assistance has not been considered an important arena in broader efforts aimed at curbing corruption, and corruption has not always been considered a particularly important concern for humanitarian assistance despite the obviously challenging nature of the context of humanitarian emergencies. Corruption, though, is a threat to humanitarian action because it can prevent assistance from getting to the people who most need it, and because it can potentially undermine public support for such assistance. This paper examines perceptions of corruption and its affects, documents best practices, and outlines gaps in understanding. It suggests recommendations for improving the capacity of humanitarian agencies to prevent and manage the risk of corruption. Agencies have taken steps to combat corruption and improve accountability--downwards and upwards--but scope remains for improvement and for greater sharing of learning and good practice.  相似文献   
43.
Collective payments for ecosystem services (PES) programs make payments to groups, conditional on specified aggregate land-management outcomes. Such collective contracting may be well suited to settings with communal land tenure or decision-making. Given that collective contracting does not require costly individual-level information on outcomes, it may also facilitate conditioning on additionality (i.e., conditioning payments upon clearly improved outcomes relative to baseline). Yet collective contracting often suffers from free-riding, which undermines group outcomes and may be exacerbated or ameliorated by PES designs. We study impacts of conditioning on additionality within a number of collective PES designs. We use a framed field-laboratory experiment with participants from a new PES program in Mexico. Because social interactions are critical within collective processes, we assess the impacts from conditioning on additionality given: (1) group participation in contract design, and (2) a group coordination mechanism. Conditioning on above-baseline outcomes raised contributions, particularly among initially lower contributors. Group participation in contract design increased impact, as did the coordination mechanism.  相似文献   
44.
Abstract: Human–carnivore conflict is manifested in the death of humans, livestock, and carnivores. The resulting negative local attitudes and retribution killings imperil the future of many endangered carnivores. We tailored existing management tools to create a framework to facilitate the selection of actions to alleviate human–carnivore conflict and applied the framework to the human–tiger conflict in the Bangladesh Sundarbans. We identified potential actions that consider previous management efforts, local knowledge, cost‐effectiveness, fieldwork experience of authors and project staff, previous research on tiger ecology by the authors, and recommendations from human–carnivore conflict studies in other countries. Our framework includes creation of a profile to improve understanding of the nature of the conflict and its underlying causality. Identified actions include deterrents, education, direct tiger management, and response teams. We ranked actions by their potential to reduce conflict and the monetary cost of their implementation. We ranked tiger‐response teams and monitoring problem tigers as the two best actions because both had relatively high impact and cost‐effectiveness. We believe this framework could be used under a wide range of human–wildlife conflict situations because it provides a structured approach to selection of mitigating actions.  相似文献   
45.
Integrated Water Resource Management (IWRM) emerged as a popular concept in the water sector in the 20th century. From a highly techno-centric approach in the past, it has taken a new turn embracing Habermasian communicative rationality as a place-based nexus for multiple actors to consensually and communicatively integrate decisions in a hydrological unit. The 'how to integrate' approach had remarkable appeal worldwide in promoting authentic participation of all stakeholders. However, critics argue that the domain of water resource management is a political process of contestation and negotiation; the emphasis is on complexities, contextuality, power dynamics and the importance of analysing real world situations. They demonstrate 'how integration cannot be achieved' given the power dynamics in social interactions. These apparently contradictory discourses draw on different theoretical paradigms and polarise the discourse on IWRM, without offering constructive alternatives. To this end, this paper offers an option to complement this polarised discourse by examining 'how integration actually does take place' in a strategic context thereby facilitating consensual decisions to integrate water management for a sustainable future.  相似文献   
46.
This article considers the dispute between moral economy and rational peasant theories of agrarian societies in application to problems of collective action. The moral-economy theory holds that traditional peasant society is organized cooperatively through shared moral values and communal institutions; while the rational-peasant theory maintains that peasant society shows the mark of rational individual calculation, leading to free-rider problems that undermine successful collective action. This article offers an abstract model of a traditional village and assesses the applicability of recent qualifications of the collective action argument to this model. It will emerge that the social characteristics of the traditional village embody features that facilitate collective action by rational peasants.  相似文献   
47.
对情境意识的定义、活动机制、测量方法及强化方法等进行了述评。分析了关于情境意识研究的问题及趋势。  相似文献   
48.
The article discusses agricultural practices in sub-Saharan Africa, especially in terms of maintaining soil fertility. It disagrees with alarmist tendencies in the current debate, exaggerating the state of soil impoverishment in the African region. Nor does it subscribe to the idea that the remedy lies primarily in a massive influx of chemical fertilisers, especially phosphorus.
Instead, the article advocates a more balanced approach, where soil nutrient replenishment, as an improvement in natural capital, is but one part of the investment African agriculture needs. To achieve sustainable rural livelihoods, other forms of capital are also required, such as physical capital, i.e. infrastructure (roads, means of communication); financial capital in the form of credit and savings schemes; and human- and social capital, especially improved access to information and knowledge for farmers as well as improved local organisation and empowerment.
The article reviews nine case studies, taken from different climate zones in the region and representing different soil conditions. All case studies were projects using the participatory learning and action research (PLAR) method, which is discussed in detail.  相似文献   
49.
Prompted by the calls in recent years to link relief practice to peace-building, development, or both, several conferences and papers have recently mounted a strong critique, seeing these 'broadenings' of relief as 'eroding' or 'corrupting' core humanitarian principles and playing into neo-isolationist agendas to slash humanitarianism. This paper argues that whereas these critiques have important goals in mind when they encourage a concentration on the basics of relief, there has been a loss of subtlety in the ensuing debate. Considering each element of the debate in turn, the paper argues that there is more common ground between 'new' and 'old', 'broadened' and 'basics' relief than at first appears. In concluding, it is argued that further research on key questions, and an openness to hear all perspectives will get us further than entrenched positions and rallying cries.  相似文献   
50.
The southern Africa crisis represents the first widespread emergency in a region with a mature HIV/AIDS epidemic. It provides a steep learning curve for the international humanitarian system in understanding and responding to the complex interactions between the epidemic and the causes and the effects of this crisis. It also provoked much debate about the severity and causes of this emergency, and the appropriateness of the response by the humanitarian community. The authors argue that the over-emphasis on food aid delivery occurred at the expense of other public health interventions, particularly preventative and curative health services. Health service needs were not sufficiently addressed despite the early recognition that ill-health related to HIV/AIDS was a major vulnerability factor. This neglect occurred because analytical frameworks were too narrowly focused on food security, and large-scale support to health service delivery was seen as a long-term developmental issue that could not easily be dealt with by short-term humanitarian action. Furthermore, there were insufficient countrywide data on acute malnutrition, mortality rates and performance of the public health system to make better-balanced evidence-based decisions. In this crisis, humanitarian organisations providing health services could not assume their traditional roles of short-term assistance in a limited geographical area until the governing authorities resume their responsibilities. However, relegating health service delivery as a long-term developmental issue is not acceptable. Improved multisectoral analytical frameworks that include a multidisciplinary team are needed to ensure all aspects of public health are dealt with in similar future emergencies. Humanitarian organisations must advocate for improved delivery and access to health services in this region. They can target limited geographical areas with high mortality and acute malnutrition rates to deliver their services. Finally, to address the underlying problem of the health sector gap, a long-term strategy to ensure improved and sustainable health sector performance can only be accomplished with truly adequate resources. This will require renewed efforts on part of governments, donors and the international community. Public health interventions, complementing those addressing food insecurity, were and are still needed to reduce the impact of the crisis, and to allow people to re-establish their livelihoods. These will increase the population's resilience to prevent or mitigate future disasters.  相似文献   
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