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131.
Diego Rubolini Maria Romano Roberta Martinelli Barbara Leoni Nicola Saino 《Behavioral ecology and sociobiology》2006,59(4):549-560
Mothers may profoundly affect offspring phenotype and performance by adjusting egg components, including steroid hormones.
We studied the effects of elevated prenatal testosterone (T) exposure in the ring-necked pheasant on the expression of a suite
of male and female traits, including perinatal response to stress, immune response, growth, and secondary sexual traits. Prenatal
T levels were increased by injecting the yolk of unincubated eggs with physiological doses of the hormone. Yolk T injection
resulted in a reduced length of male tarsal spurs, a trait which positively predicts male success in intra- and intersexual
selection and viability, whereas no direct effect on male wattle characteristics or plumage traits of either sex was observed.
Female spur length was also negatively affected by T, but to a lesser extent than in males. In addition, the covariation between
male secondary sexual traits, which are reliable quality indicators, differed between T and control males, suggesting that
the manipulation may have altered the assessment of overall male quality by other males and females. In conclusion, the negative
effects of elevated yolk T on spur length, a trait which positively predicts male fitness, coupled with the lack of effects
on growth or other traits in both sexes, provided limited evidence for mothers being subjected to a trade-off between positive
and negative consequences of yolk T deposition on offspring traits and suggest that directional selection for reduced yolk
T levels may occur in the ring-necked pheasant. 相似文献
132.
Emmanuel Fort Laure Pourcel Philippe Davezies Camille Renaux Mireille Chiron Barbara Charbotel 《Safety Science》2010,48(10):1412-1420
Road accidents sustained at work represent between 20% and 40% of work fatalities in most industrialised countries, yet few data on occupational road accident risk factors have been published. A case control study was performed to assess the role of work-related risk factors in the occurrence of occupational road accidents. A preliminary qualitative study was carried out to identify possible occupational factors in occupational road accidents, and to draw up the case control study. Cases were recruited from the Rhône road trauma registry (France), controls from voting lists. A telephone interview was performed. Exposure to road risk was measured as a percentage of work time. One hundred and forty-six cases and 440 matched controls were interviewed. Accident risk was found to increase with exposure. Driving was associated with more difficult working conditions than found in jobs not involving driving. These difficulties, however, were not systematically associated with increased occupational road accident risk. Among factors which still emerge after adjustment for road risk exposure, there are scheduling issues (inflexible schedule organisation, lack of consecutive rest-days, lack of flexibility in performing the work), difficulties of communication with superiors, low seniority in the activity, low educational level and physical constraints at work. This study highlights some possible occupational road accident risk factors. Given the chosen case/control methodology, the findings may be considered as advancing our knowledge of the subject, but need confirmation by further studies. 相似文献
133.
Barbara S. Lawrence 《组织行为杂志》1984,5(1):23-35
The age distribution within an organization forms an implicit career timetable, and there is evidence that people use their perceptions of this timetable to determine whether their careers are on or off schedule. Questionnaire data were collected from managers (N = 488, 47 per cent) within a large electric utility. The results indicate that managers who see themselves as ‘behind time’ in their careers have more negative attitudes towards work than other managers, even when their perceptions of being ‘behind time’ are inaccurate. However, although these managers continue to have the most negative attitudes, differences between the on and off schedule managers are smaller when their position on the actual career timetable is controlled. Thus, work attitudes are influenced by both individual and demographic factors. Finally, the longer managers remain in the same job, the more likely they are to define themselves as ‘behind time’. This supports other research suggesting that lateral moves within organizations may be an important device for managing the normal -limitations of upward movement in managerial careers. 相似文献
134.
Mariana Egler Claudio Antonio Gonçalves Egler Barbara Franz Maria Silvia Muylaert de Araujo Marcos Aurélio Vasconcelos de Freitas 《Regional Environmental Change》2013,13(2):263-271
In recent years, Amazonian deforestation has become a question of global concern. Deforestation in Amazon is a complex phenomenon in nature and has been related to traditional agriculture expansion. In this work, land use, socioeconomic and conservation indicators, combined with statistical analysis, were used to understand forces associated with patterns of deforestation. This approach was applied in Southern Brazilian Pre-Amazon in Mato Grosso State, which represents an extensive rain forest-savanna ecotone, located in the south border of Amazon biome. Based on data from the last two agricultural censuses (1995/1996–2006), we compared agricultural expansion in this area and Mato Grosso state. Results have shown that 85 % of state deforestation was concentrated in Southern Pre-Amazon and was closely related to increase in number of cattle and pasture area. PCA results pointed that population (92 %), number of cattle (86.5 %), pastures (84.2 %) and tractors (78.4 %) were variables with highest positive correlation to deforestation. It showed that GDP contributes to an individual axis and has a low correlation to deforestation (37.8 %). Conservation units and indigenous reserves also contribute to a single axis and were negatively correlated to temporary crops area. Results revealed a significant reduction in production and commercialization of extractive products in the region, revealing that the main, almost only conservation policy in Mato Grosso remains the creation of Special Areas. We suggest that further studies are necessary to screen development alternatives to simple cutting trees down. It is important to diversify strategies for deforestation control, and development aspects must be more seriously considered to reach a sustainable deforestation control policy. 相似文献
135.
Scot D. Anderson Taylor K. Chapple Salvador J. Jorgensen A. Peter Klimley Barbara A. Block 《Marine Biology》2011,158(6):1233-1237
Mark-recapture techniques can be used to estimate white shark (Carcharodon carcharias) population abundance. These frameworks are based on assumptions that marks are conserved and animals are present at the sampling location over the entire duration of the study. Though these assumptions have been validated across short-time scales for white sharks, long-term studies of population trends are dependent on these assumptions being valid across longer periods. We use 22 years of photographic data from aggregation sites in central California to support the use of dorsal fin morphology as long-term individual identifiers. We identified five individuals over 16–22 years, which support the use of dorsal fins as long-time individual identifiers, illustrate strong yearly site fidelity to coastal aggregation sites across extended time periods (decades), and provide the first empirical validation of white shark longevity >22 years. These findings support the use of fin morphology in mark-recapture frameworks for white sharks. 相似文献
136.
137.
Barbara Neumann Michael Lütz Beatrice Schüpbach Erich Szerencsits 《Regional Environmental Change》2009,9(3):197-207
Spatial modelling of environmental indicators has been well established in landscape ecology and in nature conservation on
regional and national scales over the recent past. Yet, using spatial information as a basis for the coordination of environmental
measures on a trans-national European level reveals several shortcomings and hindrances, ranging from data quality issues
and methodological aspects to discussions on how to define ecological indicators across Europe. This paper analyzes the potential
of spatial modelling for the development and implementation of agri-environmental measures as part of rural development policies,
discussing critical aspects of spatial environmental modelling as well as chances, trends and demands. 相似文献
138.
High-resolution satellite locations were obtained from striped marlin using Argos transmitters attached to the upper lobe
of the caudal fin. Twenty-six striped marlin were tagged off New Zealand (2005–2007) and tracked as far as the central Pacific
Ocean. Caudal fin mounted Argos tags generated 1,524 locations during a total of 659 tracking days [mean 25 (±21.24) days
per fish and 2.3 (±2.30) locations per day]. 38% of locations have an estimated accuracy of ±1 km or better. Displacement
rates from high quality locations ranged from 2.9 to 170.8 km in a 24 h period, with a mode at 20–30 km and a mean of 45 km/day.
The caudal fin attachment methodology and antenna configuration was adjusted each season to improve transmission life and
data quality, with the best results obtained in the last year of deployments (2007). The longest track duration was 102 days,
with a total displacement of 4,959 km and a total track distance from all locations received of 6,850 km. Tag shedding and
antenna failure appear to have limited the duration of tracks from SPOT tags. The high temporal and spatial resolution data
revealed behaviours not previously observed in striped marlin, including associations to subsurface bathymetric features.
High resolution location data such as these are useful inputs for statistical models used to investigate habitat selection
and switching between different behavioural modes. The geolocations calculated using ukfsst estimates from PAT tag data had
RMS errors of 1.01° latitude and 0.59° longitude when compared with SPOT tag Argos locations. 相似文献
139.
Jacqueline Loos Felipe Benra Marta Berbs-Blzquez Leah L. Bremer Kai M. A. Chan Benis Egoh Maria Felipe-Lucia Davide Geneletti Bonnie Keeler Bruno Locatelli Lasse Loft Barbara Schrter Matthias Schrter Klara J. Winkler 《Ambio》2023,52(3):477
Mainstreaming of ecosystem service approaches has been proposed as one path toward sustainable development. Meanwhile, critics of ecosystem services question if the approach can account for the multiple values of ecosystems to diverse groups of people, or for aspects of inter- and intra-generational justice. In particular, an ecosystem service approach often overlooks power dimensions and capabilities that are core to environmental justice. This article addresses the need for greater guidance on incorporating justice into ecosystem services research and practice. We point to the importance of deep engagement with stakeholders and rights holders to disentangle contextual factors that moderate justice outcomes on ecosystem service attribution and appropriation in socio-political interventions. Such a holistic perspective enables the integration of values and knowledge plurality for enhancing justice in ecosystem services research. This broadened perspective paves a way for transformative ecosystem service assessments, management, and research, which can help inform and design governance structures that nourish human agency to sustainably identify, manage, and enjoy ecosystem services for human wellbeing. 相似文献
140.
Barbara Walna Iwona Kurzyca Ewa Bednorz Leszek Kolendowicz 《Environmental monitoring and assessment》2013,185(7):5497-5514
A 2-year study (2010–2011) of fluorides in atmospheric precipitation in the open area and in throughfall in Wielkopolski National Park (west-central Poland) showed their high concentrations, reaching a maximum value of 2 mg/l under the tree crowns. These high values indicate substantial deposition of up to 52 mg/m2/year. In 2011, over 51 % of open area precipitation was characterized by fluoride concentration higher than 0.10 mg/l, and in throughfall such concentrations were found in more than 86 % of events. In 2010, a strong connection was evident between fluoride and acid-forming ions, and in 2011, a correlation between phosphate and nitrite ions was seen. Analysis of available data on F? concentrations in the air did not show an unequivocal effect on F? concentrations in precipitation. To find reasons for and source areas of high fluoride pollution, the cases of extreme fluoride concentration in rainwater were related to atmospheric circulation and weather patterns. Weather conditions on days of extreme pollution were determined by movement of weather fronts over western Poland, or by small cyclonic centers with meteorological fronts. Macroscale air advection over the sampling site originated in the western quadrant (NW, W, and SW), particularly in the middle layers of the troposphere (2,500–5,000 m a.s.l.). Such directions indicate western Poland and Germany as possible sources of the pollution. At the same time in the lower troposphere, air inflow was frequently from the north, showing short distance transport from local emitters, and from the agglomeration of Poznań. 相似文献