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291.
Community gardens (CGs) in university settings are faced with challenges associated with a transient and inexperienced population of student gardeners, but they also have the potential to have a lasting impact on the food behaviours of many young people. This paper undertakes a systematic critical review of literature about University Community Gardens for Sustainability (UCGS) in order to suggest directions of future research in the emerging field research about CGs within and outside of universities. The literature shows that UCGS have similar benefits to those identified in urban CG literature; but with greater emphasis on both the educational and environmental sustainability benefits, suggesting an under-used potential of CGs in these areas. We argue that a better understanding of the particular challenges and benefits of UCGS could improve outcomes of CGs in all settings. Therefore we recommend that future should explore: (1) participant transience in CGs, thereby helping sustainability projects with large volunteer bases learn to cope with challenges this poses in order to maximise the garden’s impacts; (2) whether/how participating in CGs can contribute to changes in attitudes/behaviours with regards to sustainability and be used as a tool for Education for Sustainability in and outside of university settings and (3) failed cases of CGs to genuinely understand factors that contribute to success. By addressing these areas we can improve our understanding of how community gardening can contribute to our communities, universities and environment, and can begin to make these potential contributions a reality.  相似文献   
292.
Objectives: The Insurance Institute for Highway Safety (IIHS) rates front seat/head restraint designs using a combination of static and dynamic measurements following RCAR-IIWPG procedures. The purpose of this study was to determine whether vehicles with better IIHS-rated seats/head restraints had lower injury risk in rear-end collisions and how the effect of better rated seats interacted with driver gender and age.

Methods: The presence of an associated insurance injury claim was determined for rear-impact crashes using 2001–2014 model year cars and SUVs. Logistic regression was used to compare injury risk for vehicles with good, acceptable, and marginal IIHS-rated seats/head restraints with poor-rated seats/head restraints. Analyses were run by gender and driver age and also by the rate of more severe injury claims.

Results: Injury rates were 11.2% lower for vehicles with seats/head restraints rated good compared to vehicles with seats/head restraints rated poor. The percentage reduction for good- versus poor-rated seats was greater for females (12.7%) than males (8.9%). Comparing good- with poor-rated seats, driver ages 15–24 had the largest reduction at 19.8%, followed by 10.7% for driver ages 45–64 and 10.4% for driver ages 25–44.

Conclusions: Seats/head restraints with better IIHS ratings are associated with lower injury rates in rear-impact collisions than seats rated poor. The reductions in injury rates were strongest for females and for young-to–middle-age drivers. The strong reductions in injury rates for these groups are encouraging given their high initial injury rates.  相似文献   

293.
Agri-environment schemes (AES) are widely used policy instruments intended to combat widespread biodiversity declines across agricultural landscapes. Here, using a light trapping and mark-release-recapture study at a field-scale on nine common and widespread larger moth species, we investigate the effect of wide field margins (a popular current scheme option) and the presence of hedgerow trees (a potential scheme option in England) on moth abundance. Of these, we show that wide field margins positively affected abundances, although species did not all respond in the same way. We demonstrate that this variation can be attributed to species-specific mobility characteristics. Those species for which the effect of wide margins was strongest covered shorter distances, and were more frequently recaptured at their site of first capture. This demonstrates that the standard, field-scale uptake of AES may be effective only for less mobile species. We discuss that a landscape-scale approach, in contrast, could deliver significant biodiversity gains, as our results indicate that such an approach (perhaps delivered through targeting farmers to join AES) would be effective for the majority of wider countryside species, irrespective of their mobility level.  相似文献   
294.
Recently, evidence is mounting that females can adaptively engineer the quality of their offspring via the deposition of yolk compounds, including carotenoids and androgens. In this study, we simultaneously consider how both carotenoids and androgens in egg yolk relate to parental quality in barn swallows (Hirundo rustica erythrogaster). First, we found no relationship between concentrations or amounts of yolk androgens and carotenoids. Yolk carotenoids decreased with laying order, whereas we found no relationship between yolk androgens and laying order. Second, we tested the Investment Hypothesis, which predicts that high-quality females or females paired to high quality mates, allocate differentially more of these yolk compounds to their offspring. For carotenoids, we mostly found evidence to counter predictions of the Investment hypothesis: (1) Carotenoid concentrations varied among females, (2) heavier eggs contained lower carotenoid concentrations, although heavier yolks contained greater amounts of carotenoids, (3) eggs of earlier-laying females had lower concentrations in their eggs, and (4) yolk carotenoids were not correlated with clutch size or male plumage ornamentation. For androgens, we found weak support for the Investment Hypothesis: (1) Yolk androgens varied among females, (2) heavier eggs and yolks contained greater amounts, although not concentrations of androgens, (3) females paired to more colorful males laid eggs with greater concentrations of androgens, and (4) no effects of laying date or morphological correlates of female quality on androgen concentrations in egg yolks. Overall, these findings suggest that each yolk compound may have different functions and therefore may be regulated by different mechanisms.  相似文献   
295.
Loss of forest cover is a likely consequence of climate change in many parts of the world. To test the vulnerability of eucalypt forests in Australia’s island state of Tasmania, we modelled tree canopy cover in the period 2070–2099 under a high-emission scenario using the current climate–canopy cover relationship in conjunction with output from a dynamically downscaled regional climate model. The current climate–canopy cover relationship was quantified using Random Forest modelling, and the future climate projections were provided by three dynamically downscaled general circulation model (GCM) simulations. Three GCMs were used to show a range of projections for the selected scenario. We also explored the sensitivity of key endemic and non-endemic Tasmanian eucalypts to climate change. All GCMs suggested that canopy cover should remain stable (proportional cover change <10 %) across ~70 % of the Tasmanian eucalypt forests. However, there were geographic areas where all models projected a decline in canopy cover due to increased summer temperatures and lower precipitation, and in addition, all models projected an increase in canopy cover in the coldest part of the state. The model projections differed substantially for other areas. Tasmanian endemic species appear vulnerable to climate change, but species that also occur on the mainland are likely to be less affected. Given these changes, restoration and carbon sequestration plantings must consider the species and provenances most suitable for future, rather than present, climates.  相似文献   
296.
Continued development of personal air pollution monitors is rapidly improving government and research capabilities for data collection. In this study, we tested the feasibility of using GPS-enabled personal exposure monitors to collect personal exposure readings and short-term daily PM2.5 measures at 15 fixed locations throughout a community. The goals were to determine the accuracy of fixed-location monitoring for approximating individual exposures compared to a centralized outdoor air pollution monitor, and to test the utility of two different personal monitors, the RTI MicroPEM V3.2 and TSI SidePak AM510. For personal samples, 24-hr mean PM2.5 concentrations were 6.93 μg/m3 (stderr = 0.15) and 8.47 μg/m3 (stderr = 0.10) for the MicroPEM and SidePak, respectively. Based on time–activity patterns from participant journals, exposures were highest while participants were outdoors (MicroPEM = 7.61 µg/m3, stderr = 1.08, SidePak = 11.85 µg/m3, stderr = 0.83) or in restaurants (MicroPEM = 7.48 µg/m3, stderr = 0.39, SidePak = 24.93 µg/m3, stderr = 0.82), and lowest when participants were exercising indoors (MicroPEM = 4.78 µg/m3, stderr = 0.23, SidePak = 5.63 µg/m3, stderr = 0.08). Mean PM2.5 at the 15 fixed locations, as measured by the SidePak, ranged from 4.71 µg/m3 (stderr = 0.23) to 12.38 µg/m3 (stderr = 0.45). By comparison, mean 24-h PM2.5 measured at the centralized outdoor monitor ranged from 2.7 to 6.7 µg/m3 during the study period. The range of average PM2.5 exposure levels estimated for each participant using the interpolated fixed-location data was 2.83 to 19.26 µg/m3 (mean = 8.3, stderr = 1.4). These estimated levels were compared with average exposure from personal samples. The fixed-location monitoring strategy was useful in identifying high air pollution microclimates throughout the county. For 7 of 10 subjects, the fixed-location monitoring strategy more closely approximated individuals’ 24-hr breathing zone exposures than did the centralized outdoor monitor. Highlights are: Individual PM2.5 exposure levels vary extensively by activity, location and time of day; fixed-location sampling more closely approximated individual exposures than a centralized outdoor monitor; and small, personal exposure monitors provide added utility for individuals, researchers, and public health professionals seeking to more accurately identify air pollution microclimates.

Implications: Personal air pollution monitoring technology is advancing rapidly. Currently, personal monitors are primarily used in research settings, but could they also support government networks of centralized outdoor monitors? In this study, we found differences in performance and practicality for two personal monitors in different monitoring scenarios. We also found that personal monitors used to collect outdoor area samples were effective at finding pollution microclimates, and more closely approximated actual individual exposure than a central monitor. Though more research is needed, there is strong potential that personal exposure monitors can improve existing monitoring networks.  相似文献   
297.
Building trust between resource users and natural resource institutions is essential when creating conservation policies that rely on stakeholders to be effective. Trust can enable the public and agencies to engage in cooperative behaviors toward shared goals and address shared problems. Despite the increasing attention that trust has received recently in the environmental management literature, the influence that individual cognitive and behavioral factors may play in influencing levels of trust in resource management institutions, and their associated scientific assessments, remains unclear. This paper uses the case of fisheries management in the northeast to explore the relationships between an individual’s knowledge of the resource, perceptions of resource health, and participatory experience on levels of trust. Using survey data collected from 244 avid recreational anglers in the Northeast U.S., we test these relationships using structural equation modeling. Results indicate that participation in fisheries management is associated with increased trust across all aspects of fisheries management. In addition, higher ratings of resource health by anglers are associated with higher levels of trust of state and regional institutions, but not federal institutions or scientific methods.  相似文献   
298.
The Jamaica Bay portion of Gateway National Recreation Area, located next to highly urbanized New York City, faces many challenges to preserve and protect its natural, cultural, and recreational resources. To aid in the management of the park resources, detailed estuarine shoreline analyses of Jamaica Bay were undertaken using imagery taken in 1951, 1974, and 2006. A 15-class land use/land cover (LULC) classification scheme was created after doing an initial examination of the types of LULC in the 2006 orthoimagery and then applied in the analyses of the previous years. By quantifying how and where the shoreline has changed over the past 60 years, park managers can better assess the impact of management practices by comparing LULC of the shoreline within the park boundary to the LULC of the shoreline outside the park boundary before and after the park was created in 1972. Despite the heavy development of New York City and the trend for shoreline modification, the overall shoreline of Jamaica Bay has maintained large percentages of undeveloped vegetation and sandy beaches. Much of the LULC change has occurred in the creeks as a result of dredging and shape modification for residential and commercial uses. Park management has been effective in limiting the alteration of undeveloped shoreline although there have been significant changes in the relative percentages of sand and vegetated beaches between 1974 and 2006.  相似文献   
299.
ABSTRACT

In 1996, Schwartz, Dockery, and Neas1 reported that daily mortality was more strongly associated with concentrations of PM2.5 than with concentrations of larger particles (coarse mass [CM]) in six U.S. cities (“original paper'V'original analyses”). Because of the public policy implications of the findings and the uniqueness of the concentration data, we undertook a reanalysis of these results. This paper presents results of the reconstruction of these data and replication of the original analyses using the reconstructed data. The original investigators provided particulate air pollution data for this paper. Daily weather and daily counts of total and cause-specific deaths were reconstructed from original public records. The reconstructed particulate air pollution and weather data were consistent with the summaries presented in the original paper. Daily counts of deaths in the reconstructed data set were lower than in the original paper because of restrictions on residence and place of death. The reconstruction process identified an administrative change in county codes that led to higher numbers of deaths in St. Louis. Despite these differences in daily counts of deaths, the estimated effects of par-ticulate air pollution from the reconstructed dataset, using analytic methods as described in the original paper, produced combined effect estimates essentially equivalent to the originally published results. For example, the estimated association of a 10 |j.g/m3 increase in 2-day mean particulate air pollution on total mortality was 1.3% (95% confidence interval [CI] 0.9-1.7%, t = 6.53) for PM25 based on the reconstructed dataset, compared to the originally reported association of 1.5% (95% CI 1.1-1.9%, t = 7.41). For coarse particles, the estimated association from the reconstructed dataset was 0.4% (95% CI -0.2-0.9%, t = 1.43) compared to the originally reported association of 0.4% (95% CI -0.1-1.0%, t = 1.48). These results from the reconstructed data suggest that the original results reported by Schwartz, Dockery, and Neas1 were essentially replicated.  相似文献   
300.
ABSTRACT

The Clean Air Act mandates that sensitive subpopulations be considered in setting standards to protect the public's health. The purposes of this paper are to point out different conceptualizations of susceptibility, examine how it is approached in risk-related processes, and recommend ways it may be more explicitly framed for risk assessment and management purposes. We studied the traditional risk assessment paradigm, the U.S. Environmental Protection Agency (EPA) guidelines and revised PM standard, discussions from recent interdisciplinary meetings, and peer-reviewed literature. Areas of controversy include what factors intrinsic and extrinsic to the host should be incorporated in susceptibility, what health endpoints are of concern, whether susceptibility is deterministic or stochastic, and whether it should be defined on an individual or population scale. Recent discussions about susceptibility applied to PM indicate that it needs to be more clearly defined and evaluated for scientific and policy purposes. We conclude that varying concepts of susceptibility can affect risk-related processes such as PM standard setting. We recommend that susceptibility be clearly defined in the problem statement of risk assessments and be addressed in a specific subsection of risk characterization, integrating all susceptibility findings from the prior three  相似文献   
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