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241.
Michael?M.?WebsterEmail author Paul?J.?B.?Hart 《Behavioral ecology and sociobiology》2006,60(1):77-86
Any mechanism that allows animals to increase their foraging efficiency is likely to be selected for, including the ability
to learn to recognise and subsequently discriminate between habitat types based on their profitability. In a series of laboratory
studies, we manipulated prey densities across two different experimental subhabitats and demonstrated that threespine stickleback
(Gasterosteus aculeatus) can develop foraging preferences for subhabitats that have previously yielded prey. Fish were not recalling the spatial
location of prey patches; rather, they were discriminating between subhabitats based on foraging experience there and allocating
foraging effort accordingly. Foraging preferences took around 14 days to develop, and once established, they persisted independently
of experimental prey density, suggesting that fish were using experience rather than real-time sampling to select foraging
grounds. When we presented focal fish with social information cues, we found that they preferentially used local enhancement
and current public information cues when they conflicted with previous experience, but that they did not use prior public
information. This suggests that in the presence of conspecifics, individuals prioritise social conformity over the use of
private information. We discuss our results in the context of optimal foraging and the trade-offs associated with balancing
conflicting private and social information. 相似文献
242.
Modeling and analysis of nest-site selection by honeybee swarms: the speed and accuracy trade-off 总被引:5,自引:2,他引:3
Nest-site selection in honeybees is a process of social decision making in which the scout bees in a swarm locate several
potential nest sites, evaluate them, and select the best one by means of competitive signaling. We develop a model of this
process and validate that the model possesses the key features of the bees' decision-making process, as revealed by prior
empirical studies. Next, we use the model to study the “design” of the nest-site selection process, with a focus on how certain
behavioral parameters have been tuned by natural selection to achieve a balance between speed and accuracy. First, we study
the effects of the quorum threshold and the dance decay rate. We show that evolution seems to have settled on values for these
two parameters that seek a balance between speed and accuracy of decision making by minimizing the time needed to achieve
a consensus and maximizing the probability that the best site is chosen. Second, we study the adaptive tuning of the tendency
of bees to explore for vs be recruited to a site. We show that this tendency appears to be tuned to regulate the positive
feedback process of recruitment to ensure both a reasonably rapid choice and a low probability of a poor choice. Finally we
show that the probability of choosing the best site is proportional to its quality, but that this proportionality depends
on its quality relative to other discovered sites.
相似文献
Thomas D. SeeleyEmail: |
243.
Ecological indicators can facilitate an adaptive management approach, but only if acceptable levels for those indicators have
been defined so that the data collected can be interpreted. Because acceptable levels are an expression of the desired state
of the ecosystem, the process of establishing acceptable levels should incorporate not just ecological understanding but also
societal values. The goal of this research was to explore an approach for defining acceptable levels of ecological indicators
that explicitly considers social perspectives and values. We used a set of eight indicators that were related to issues of
concern in the Lake Champlain Basin. Our approach was based on normative theory. Using a stakeholder survey, we measured respondent
normative evaluations of varying levels of our indicators. Aggregated social norm curves were used to determine the level
at which indicator values shifted from acceptable to unacceptable conditions. For seven of the eight indicators, clear preferences
were interpretable from these norm curves. For example, closures of public beaches because of bacterial contamination and
days of intense algae bloom went from acceptable to unacceptable at 7–10 days in a summer season. Survey respondents also
indicated that the number of fish caught from Lake Champlain that could be safely consumed each month was unacceptably low
and the number of streams draining into the lake that were impaired by storm water was unacceptably high. If indicators that
translate ecological conditions into social consequences are carefully selected, we believe the normative approach has considerable
merit for defining acceptable levels of valued ecological system components. 相似文献
244.
The INDICATE safety program: evaluation of a method to proactively improve airline safety performance 总被引:1,自引:0,他引:1
A number of recent and highly publicised fatal aircraft accidents, within the Australian regional airline industry, has highlighted the need for operators of regular public transport aircraft to be more proactive in identifying and addressing aviation safety hazards. Despite this need, there are currently few proactive safety management programs that are practical, simple, cost effective and which reliably demonstrate improvements in airline safety performance. This paper outlines a new proactive airline safety program called INDICATE (Identifying Needed Defences In the Civil Aviation Transport Environment) that has been applied within the Australian regional airline industry. To evaluate the INDICATE program, a major Australian regional airline agreed to implement the program in one of its operational bases while another base was used as a control group. Five evaluation criteria were applied to determine whether the program would have a positive influence on the airline's safety performance. These criteria included airline safety culture, staff risk perception of aviation safety hazards, willingness of staff to report safety hazards, action taken on identified safety hazards and staff comments about safety management within the airline. Results from the trial suggest that the program can have a positive influence on airline safety performance, specifically: improving staff confidence in how safety is managed, increasing staff willingness to report safety hazards and incidents, improving organisational safety culture and reducing staff perceptions of the severity and likelihood of safety hazards occurring within the airline. The success of the trial has resulted in a number of Australian and International airlines adopting the program. 相似文献
245.
Using two very different empirical settings, this paper emphasizes the required conditions for the successful crafting of sustainable institutions. In the first setting, different farmer groups in Cambodia and Vietnam try to establish a collective approach for small-scale community-based aquaculture and fail. In the second setting, the collective initiatives of urban women in India are analysed. The Indian women succeed in their objective of a fuel transition from firewood to gas cookers using a cooperative approach. Ostrom's variables identified in the “Multitier Framework for Analyzing Social–Ecological Systems (SES)” (Ostrom, 2007) are applied to local collective action initiatives in both settings to understand which factors make some of the groups succeed in their objectives and others fail. This research highlights the complexity as well as the uniqueness of different SESs. At the same time, the paper contributes to demonstrating the usability of the SES and certain variables to estimate the likelihood of success of self-organisation and crafting of rules. It highlights the relevance of certain conceptual variables for sustainable or unsustainable outcomes for different cases. 相似文献
246.
Wouter T. De Groot Haranath Tadepally 《Environment, Development and Sustainability》2008,10(4):519-536
In southern India, tens of thousands of village-level irrigation systems (‘tanks’ and feeder channels) are in disrepair. This
paper analyses the results of a local NGO effort that focused on awareness-raising and advice to bring about self-sustained
community action for irrigation system restoration. After designing a model structure that contains both motivational and
capacity (social capital) factors, it is found that (pre-existing) collective social capital, as measured through five simple
indicators, strongly correlates with success of the NGO strategy. The intensity of the NGO’s effort shows a negative correlation
with success, however. The discussion focuses on issues of social capital definition and measurement and the practical implications
of the concept for environmental action, especially the difference between using existing social capital for environmental
management versus the construction of social capital as a basis for later self-sustained environmental work.
Readers should send their comments on this paper to BhaskarNath@aol.com within 3 months of publication of this issue. 相似文献
247.
International cooperation and learning may accelerate climate change adaptation and help countries and regions to adapt more effectively and efficiently. Recognizing the importance and opportunities for mutual learning and knowledge transfer, international and supranational organizations, such as the European Commission, have put programmes for international cooperation in place. This paper presents and tests a framework for assessing multi-level learning outcomes of such international cooperation processes and the conditions that produce these outcomes. The framework distinguishes between: (1) group learning by individual process participants; (2) organizational learning by organizations represented in the process; and (3) network and societal learning by actors external to the process. We verify the analytical potential of the framework by comparing learning by six partners in an adaptation-oriented European cooperation project. The project scores rather high on group learning with participants learning from and – to a lesser extent – also with each other. Learning by partner organizations varied and was generally less whereas learning by external actors was very limited. The case study confirms our expectation that learning outcomes are produced by combinations of partner-specific, process-specific and process-external conditions. The presented framework and insights can be used to stimulate learning in and from international cooperation processes. 相似文献
248.
Over the past 30 years, urban environmental pollution governance has been increasingly influenced by ideas of New Public Management. However, there is increasing evidence that it is failing in its promise to deliver efficient and effective regulation. The critiques are mounting of risk-based approaches, where regulators are increasingly accountable for the costs (and benefits) of their interventions upon firms.There is a particular lack of research on the role of conduct and practices involved on the ‘front line’ of regulation. This constrains our ability to understand how more efficient effective urban environmental pollution control might develop. This paper focuses on the regulator field officers and business duty holders of environmental compliance, who have direct contact in the processes and administration of regulation. Applying theories of social practice to environmental regulation, the paper provides new insights into compliance and enforcement practices, as these workers seek to prevent pollution, remediate sites and manage waste. The analysis reveals disconnects between expectations of enforcing and managing compliance; and between practices of policing and polluting.Using an ethnographic-informed approach to understand the social practices of regulation has not been attempted in this way before. It reveals new insights into limitations of current approaches to regulation, and indicates interventions that could lead to improved compliance outcomes in a post-New Public Management era in urban pollution governance. 相似文献
249.
D. S. Pope 《Behavioral ecology and sociobiology》2000,47(6):432-437
Many territorial advertisement signals are thought to be dual-function signals, directed to both rival male and receptive
female conspecifics. However, few studies have tested this assumption by examining whether in fact both sexes are likely to
elicit signaling behavior from territorial males. In this study, I experimentally manipulated the social context of male sand
fiddler crabs (Uca pugilator) to investigate the effect of different audiences on the performance of the claw-waving display, a territorial signal that
is often presumed to be directed to both males and females. To test whether males perform this signal to both audiences, I
measured the frequency of waving behavior by focal males when housed in field enclosures alone, with only males, with only
females, or with both males and females. Focal males waved at a low frequency when alone, and the presence of males had no
effect on their level of waving. However, in the presence of females, focal males showed a significantly higher level of waving,
whether or not males were also present. In addition, there was no association between fighting and waving behavior. This experiment
provides evidence that from the perspective of the signaling male, the claw-waving display of U. pugilator is not a dual-function signal but rather is primarily directed to receptive females.
Received: 16 December 1999 / Received in revised form: 1 February 2000 / Accepted: 19 February 2000 相似文献
250.
There is a growing recognition that scientific and social conflict pervades invasive species management, but there is a need for empirical work that can help better understand these conflicts and how they can be addressed. We examined the tensions and conflicts facing invasive Asian carp management in Minnesota by conducting 16 in-depth interviews with state and federal agency officials, academics, and stakeholders. Interviewees discussed the tensions and conflicts they saw impacting management, their implications, and what could be done to address them. We found three key areas of conflict and tension in Asian carp management: 1) scientific uncertainty concerning the impacts of Asian carp and the efficacy and non-target effects of possible management actions; 2) social uncertainty concerning both the lack of societal agreement on how to respond to Asian carp and the need to avoid acting from apathy and/or fear; and 3) the desired approach to research and management – whether it is informed by “political need” or “biological reality”. Our study of these tensions and conflicts reveals their importance to Asian carp management and to invasive species management, more broadly. We conclude with a discussion of possible ways to address these areas of tension and conflict, including the potential of deliberative, participatory approaches to risk-related decision making and the need to productively engage with apathy and fear. 相似文献