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91.
Recovery planning is a key component of many threatened species conservation initiatives and can be a powerful awareness raising tool. One of the largest impediments to conservation efforts in the Pacific region however, is the lack of ecological data and its subsequent effects on the development of feasible and useful recovery plans for threatened species. Without these plans, the understaffed, underfunded and often technically ill-equipped conservation agencies face huge difficulties in planning, prioritizing and conducting conservation activities to adequately protect biodiversity. The Fiji sago palm, Metroxylon vitiense, is an endemic endangered palm species whose survival is heavily dependent on a feasible species recovery plan. It is geographically restricted and threatened by habitat destruction and overexploitation for thatch for the tourism industry and palm heart consumption by local consumers. Despite its threatened status, M. vitiense is not currently protected by national or international legislation. Recent field surveys and extensive stakeholder consultation have resulted in the production of a species recovery plan highlighting the importance of the species and advocating sustainable harvesting rather than complete bans to promote conservation. This article summarizes the recovery plan and its current effects on the status of M. vitiense in Fiji. We also discuss the role of different stakeholders in the conservation of M. vitiense, including the absence of significant behavioral changes by the largest consumer - the tourism industry, and the importance of recovery plans for biodiversity conservation in the Pacific.  相似文献   
92.
In safety assessments of underground radioactive waste repositories, understanding radionuclide fate in ecosystems is necessary to determine the impacts of potential releases. Here, the reliability of two mechanistic models (the compartmental K-model and the 3D dynamic D-model) in describing the fate of radionuclides released into a Baltic Sea bay is tested. Both are based on ecosystem models that simulate the cycling of organic matter (carbon). Radionuclide transfer is linked to adsorption and flows of carbon in food chains. Accumulation of Th-230, Cs-135, and Ni-59 in biological compartments was comparable between the models and site measurements despite differences in temporal resolution, biological state variables, and partition coefficients. Both models provided confidence limits for their modeled concentration ratios, an improvement over models that only estimate means. The D-model enables estimates at high spatio-temporal resolution. The K-model, being coarser but faster, allows estimates centuries ahead. Future developments could integrate the two models to take advantage of their respective strengths.  相似文献   
93.
States, territories, and tribes identify nonpoint source pollution as responsible for more than half of the Nation’s existing and threatened water quality impairments, making it the principal remaining cause of water quality problems across the United States. Combinations of education, technical and financial assistance, and regulatory measures are used to inform landowners about nonpoint source pollution issues, and to stimulate the use of best management practices. A mail survey of non-commercial riparian landowners investigated how they learn about best management practices, the efficacy of different educational techniques, and what motivates them to implement land management activities. Landowners experience a variety of educational techniques, and rank those that include direct personal contact as more effective than brochures, advertisements, radio, internet, or television. The most important motivations for implementing best management practices were linked with elements of a personal stewardship ethic, accountability, personal commitment, and feasibility. Nonpoint source education and social marketing campaigns should include direct interpersonal contacts, and appeal to landowner motivations of caring, responsibility, and personal commitment.  相似文献   
94.
The development of effective agricultural monitoring networks is essential to track, anticipate and manage changes in the social, economic and environmental aspects of agriculture. We welcome the perspective of Lindenmayer and Likens (J. Environ. Monit., 2011, 13, 1559) as published in the Journal of Environmental Monitoring on our earlier paper, "Monitoring the World's Agriculture" (Sachs et al., Nature, 2010, 466, 558-560). In this response, we address their three main critiques labeled as 'the passive approach', 'the problem with uniform metrics' and 'the problem with composite metrics'. We expand on specific research questions at the core of the network design, on the distinction between key universal and site-specific metrics to detect change over time and across scales, and on the need for composite metrics in decision-making. We believe that simultaneously measuring indicators of the three pillars of sustainability (environmentally sound, social responsible and economically viable) in an effectively integrated monitoring system will ultimately allow scientists and land managers alike to find solutions to the most pressing problems facing global food security.  相似文献   
95.
In the early 2000s, the development of local food systems in advanced industrial countries has expanded beyond creation and support of farmers’ markets and community supported agriculture farms and projects to include targeted Buy Local Food campaigns. Non-governmental groups in many U.S. places and regions have launched such campaigns with the intent of motivating and directing consumers toward more local food purchasing in general. This article examines the current manifestations and possibilities for social justice concerns in Buy Local Food campaigns, by considering them within the more general category of “selective patronage“ campaigns. Historical campaign examples, such as Buy Union, Buy American, and Buy Black campaigns, offer instructive comparisons to contemporary consumer campaigns promoting local food. Through examining the construction of threats, intended beneficiaries, products to be avoided, and those to be preferentially selected, the paper demonstrates how selective patronage campaigns have emphasized social justice needs and concerns for designated groups in ways that have been potentially exclusionary of other disadvantaged groups and thus undermining of social justice more broadly. As a contemporary instance of “selective patronage,“ Buy Local Food campaigns exhibit similar contradictory impulses, which are intensified by the conceptual and practical pitfalls in designating “local.“ The article concludes by considering how the challenges and prospects for commitments to social justice in local food consumer campaigns reinforce the importance of emerging initiatives centered on domestic fair trade.  相似文献   
96.
97.
Aetiological understanding and screening methods for congenital heart disease (CHD) are limited. Maternal metabolomic assessment offers the potential to identify risk factors and biomarkers. We performed a systematic review (PROSPERO CRD42022308452) investigating the association between fetal/childhood CHD and endogenous maternal metabolites. Ovid-MEDLINE, Ovid-EMBASE and Cochrane Library were searched between inception and 06/09/2022. Case control studies included analysing maternal blood or urine metabolites in pregnancy or postpartum where there was foetal/childhood CHD. Risk of bias assessment utilised the Scottish Intercollegiate Guidelines Network methodology checklist and narrative synthesis was performed. A total of 134 records were screened with eight eligible studies (n = 3242 pregnancies, n = 842 CHD-affected offspring). Five studies performed metabolomic analysis in pregnancy. Metabolites distinguishing case and control groups spanned lipid, glucose and amino-acid pathways, with the development of sensitive risk prediction models. No single metabolite consistently distinguished cases and controls across studies. Three studies performed targeted analysis postnatally with altered lipid and amino acid metabolites and raised homocysteine and markers of oxidative stress identified in cases. Included studies reported small sample sizes, analysing different biosamples at variable time points using differing techniques. At present, there is not enough evidence to confidently associate maternal metabolomic profiles with offspring CHD risk. However, several identified pathways warrant further investigation.  相似文献   
98.
Kin selection has played an important role in the evolution and maintenance of cooperative breeding behaviour in many bird species. However, although relatedness has been shown to affect the investment decisions of helpers in such systems, less is known about the role that kin discrimination plays in other contexts, such as communal roosting. Individuals that roost communally benefit from reduced overnight heat loss, but the exact benefit derived depends on an individual's position in the roost which in turn is likely to be influenced by its position in its flock's dominance hierarchy. We studied the effects of kinship and other factors (sex, age, body size and flock sex ratio) on an individual's roosting position and dominance status in captive flocks of cooperatively breeding long-tailed tits Aegithalos caudatus. We found that overall, kinship had little influence on either variable tested; kinship had no effect on a bird's position in its flock's dominance hierarchy and the effect of kinship on roosting position was dependent on the bird's size. Males were generally dominant over females and birds were more likely to occupy preferred roosting positions if they were male, old and of high status. In this context, the effect of kinship on social interactions appears to be less important than the effects of other factors, possibly due to the complex kin structure of winter flocks compared to breeding groups.  相似文献   
99.
Cues for detecting and responding to perceived predation risk may be indirect, i.e., correlated with the probability of encountering a predator, or direct, i.e., produced by or related to the actual presence of a predator. Research shows, independently, both types of cues can influence anti-predator and foraging behaviours in prey species. However, since animals naturally encounter indirect and direct cues simultaneously, we were interested in quantifying their cumulative effect. Our aim was to evaluate food intake and behaviours (patch use, feeding (rate and time), vigilance) of a nocturnal mammalian herbivore to indirect (open vs. covered microhabitats; illumination) and direct (fox/owl odours) predator cues. We ran a preference trial with four paired treatments using a covered Safe food patch and an open Risk food patch, with one of four combinations of indirect and direct predator cues. Predation risk had a significant effect on both intake and behaviour (including feeding time, rate, and vigilance), but these effects differed depending on cues. No two combinations of cues produced exactly the same effects, illustrating the complexity of interactions that occur between cues. Covered patches were always perceived as less risky than open patches, but unexpectedly, open patches were perceived as riskier when dark rather than light. The strongest suite of (negative) responses to risk was associated with combined indirect and direct cues. These results highlight the importance of considering jointly, intake from a patch, intake rate, and behaviours, such as the proportion of time spent vigilant, when quantifying predation risk, rather than intake alone.  相似文献   
100.
Evolutionary theory suggests that divergent natural selection in heterogeneous environments can result in locally adapted plant genotypes. To understand local adaptation it is important to study the ecological factors responsible for divergent selection. At a continental scale, variation in climate can be important while at a local scale soil properties could also play a role. We designed an experiment aimed to disentangle the role of climate and (abiotic and biotic) soil properties in local adaptation of two common plant species. A grass (Holcus lanatus) and a legume (Lotus corniculatus), as well as their local soils, were reciprocally transplanted between three sites across an Atlantic-Continental gradient in Europe and grown in common gardens in either their home soil or foreign soils. Growth and reproductive traits were measured over two growing seasons. In both species, we found significant environmental and genetic effects on most of the growth and reproductive traits and a significant interaction between the two environmental effects of soil and climate. The grass species showed significant home site advantage in most of the fitness components, which indicated adaptation to climate. We found no indication that the grass was adapted to local soil conditions. The legume showed a significant home soil advantage for number of fruits only and thus a weak indication of adaptation to soil and no adaptation to climate. Our results show that the importance of climate and soil factors as drivers of local adaptation is species-dependent. This could be related to differences in interactions between plant species and soil biota.  相似文献   
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