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71.
72.
The ACCSEPT project, which ran from January 2006 to December 2007, identified and analysed the main factors which have been influencing the emergence of CO2 capture and geological storage (CCS) within the European Union (EU). The key clusters of factors concern science and technology, law and regulation, economics, and social acceptance. These factors have been analysed through interviews, a large-scale questionnaire conducted in 2006, and discussions in two stakeholder workshops (2006 and 2007). In Part I of this paper, we aim to distil the key messages and findings with regards to scientific, technical, legal and economic issues. There are no compelling scientific, technical, legal, or economic reasons why CCS could not be widely deployed in the forthcoming decades as part of a package of climate change mitigation options. In order to facilitate this deployment, governments at both the EU and Member State levels have an important role to play, in particular in establishing a robust and transparent legal framework (e.g. governing long-term environmental liability) and a strong policy framework providing sufficient and long-term incentives for CCS and CO2 transportation networks.  相似文献   
73.
Arm damage and loss were examined in the starfish Asterias rubens that had been caught in a variety of towed commercial fishing gears deployed on different sea bed types. Between 7% and 38% of the starfish in each catch lost one or more arms, and arm loss was positively correlated with the volume of the catch for two of the fishing gears examined. Subsequent monitoring of damaged animals showed that arms were autotomised for at least 3 weeks following capture. Mortality was highest in starfish with damaged or missing arms, compared with those that appeared intact after fishing. Arm regeneration was delayed in a small proportion of the animals caught by commercial gears. In a parallel study, 17% of starfish caught by a 4 m beam trawl had a damaged ambulacral ossicle at the point of autotomy (cf. none from a control group that were induced to autotomise under controlled conditions). There was no difference in regeneration rates between the animals caught by commercial gears and a control set (caught by a small trawl and forced to autotomise an arm in the laboratory) once the animals that delayed regeneration were excluded from the dataset. After 1 year under laboratory conditions the starfish had, on average, regenerated the missing arm to 75% of the length of the other four arms. During this time period the lengths of the undamaged arms increased by ca. 50%. The implications of this study for using arm loss in starfish as an indicator of fishing disturbance are discussed. Received: 16 August 2000 / Accepted: 20 October 2000  相似文献   
74.
The autotomy of body parts as a means of escaping predation or renewing damaged tissues has evolved in a number of animal groups. Starfishes are unique in that they can autotomise >75% of their body mass and continue to survive. Presumably, multiple autotomy of tissue has energetic costs in terms of potential fitness and may affect the allocation of energy reserves accordingly. We investigated arm autotomy, predatory capabilities and subsequent regeneration in common starfish, Asterias rubens, that were induced to lose one, two or three arms. Initially, both regeneration of autotomised arms and the rate of growth of intact arms was slowest in animals that had lost the most arms (i.e. three arms missing vs two arms missing vs one arm missing). However, 8 months later, the growth of intact arms since the start of the experiment was not significantly different between groups of starfish that had autotomised different numbers of arms. However, the average dry weight per regnerating arm was significantly higher in starfish that had autotomised the most arms. Arm loss decreased the ability of starfish to open mussels and those that had autotomised two arms were significantly less likely to feed successfully on a mussel in a 24-h period than intact starfish. Our data suggest that proportionally more energy is allocated to arm regeneration in starfish that have suffered multiple arm loss and this may compensate a potential decrease in fitness that results from decreased feeding capability.  相似文献   
75.
This dedicated issue of the Journal of the Air & Waste Management Association contains nine peer-reviewed scientific papers that were presented at the NARSTO Symposium on Tropospheric Aerosols: Science and Decisions in an International Community, held October 24-26, 2000, in Querétaro, Mexico.1 Other peer-reviewed papers2-9 appear in a companion issue of Science of the Total Environment to be published in February 2002. More than 130 papers were presented in platform and poster sessions at the meeting. Approximately 28% of the technical presentations dealt with topics from Mexico, and 15% related to Canada, with the remainder discussing U.S. and global topics.  相似文献   
76.
Granular activated carbon (GAC) exhaustion rates on pulp and paper effluent from South East Australia were found to be a factor of three higher (3.62 cf. 1.47 kg m−3) on Kraft mills compared to mills using Thermomechanical pulping supplemented by Recycled Fibre (TMP/RCF). Biological waste treatment at both mills resulted in a final effluent COD of 240 mg L−1. The dissolved organic carbon (DOC) was only 1.2 times higher in the Kraft effluent (70 vs. 58 mg L−1), however, GAC treatment of Kraft and TMP/RCF effluent was largely different on the DOC persisted after biological treatment. The molecular mass (636 vs. 534 g mol−1) and aromaticity (5.35 vs. 4.67 L mg−1 m−1) of humic substances (HS) were slightly higher in the Kraft effluent. The HS aromaticity was decreased by a factor of 1.0 L mg−1 m−1 in both Kraft and TMP/RCF effluent. The molecular mass of the Kraft effluent increased by 50 g mol−1 while the molecular mass of the TMP/RCF effluent was essentially unchanged after GAC treatment; the DOC removal efficiency of the GAC on Kraft effluent was biased towards the low molecular weight humic compounds. The rapid adsorption of this fraction, coupled with the slightly higher aromaticity of the humic components resulted in early breakthrough on the Kraft effluent. Fluorescence excitation-emission matrix analysis of the each GAC treated effluent indicated that the refractory components were higher molecular weight humics on the Kraft effluent and protein-like compounds on the TMP/RCF effluent. Although the GAC exhaustion rates are too high for an effective DOC removal option for biologically treated pulp and paper mill effluents, the study indicates that advanced organic characterisation techniques can be used to diagnose GAC performance on complex effluents with comparable bulk DOC and COD loads.  相似文献   
77.
The Anthropocene: From Global Change to Planetary Stewardship   总被引:3,自引:0,他引:3  
Over the past century, the total material wealth of humanity has been enhanced. However, in the twenty-first century, we face scarcity in critical resources, the degradation of ecosystem services, and the erosion of the planet's capability to absorb our wastes. Equity issues remain stubbornly difficult to solve. This situation is novel in its speed, its global scale and its threat to the resilience of the Earth System. The advent of the Anthropence, the time interval in which human activities now rival global geophysical processes, suggests that we need to fundamentally alter our relationship with the planet we inhabit. Many approaches could be adopted, ranging from geoengineering solutions that purposefully manipulate parts of the Earth System to becoming active stewards of our own life support system. The Anthropocene is a reminder that the Holocene, during which complex human societies have developed, has been a stable, accommodating environment and is the only state of the Earth System that we know for sure can support contemporary society. The need to achieve effective planetary stewardship is urgent. As we go further into the Anthropocene, we risk driving the Earth System onto a trajectory toward more hostile states from which we cannot easily return.  相似文献   
78.
This paper analyses patterns in beliefs about the implementation of wind power as part of a geographical comparison of onshore wind power developments in the Netherlands, North-Rhine Westphalia and England. Q methodology is applied, in order to systematically compare the patterns in stakeholder views on the institutional conditions and changes in the domains of energy policy, spatial planning and environmental policy. Three factors represent support for wind power implementation from fundamentally different perspectives. The fourth perspective is critical opposed to wind power developments as well as critical to the manner in which wind projects are proposed, planned and implemented. These four perspectives exist across the geographical cases; however, some perspectives are prominent in one case and marginal in another. This relates to different legacies and varying implementation achievements in the three cases. The analysis shows that an approach that focuses on implementing as much wind power as possible, relying on technocratic reasoning and hierarchical policies is in practice the least successful, whereas collaborative perspectives with more emphasis on local issues and less on the interests of the conventional energy sector were particularly dominant in the most successful case, North-Rhine Westphalia.  相似文献   
79.
The most widespread invasive alien plant species in South Africa’s Kruger National Park (KNP) were either introduced unintentionally along rivers and roads, or intentionally for use as ornamentals. We examine the spatial distribution of ornamental alien plants in KNP, look at the link between human population size, history, and species richness, and show how the distribution of particular species reflects the likely history of ornamental plantings. Results are used to assess whether past management actions have been appropriately directed. Two hundred and fifty-eight alien species have been recorded in the 36 tourist camps and staff villages. The number of staff housed in villages explains much of the diversity of cultivated alien plant species. Older camps also tend to have more ornamental alien plant species. However, the lack of a strong link between camp age and number of cultivated species suggests that ornamental plants have been widely spread around the KNP by humans. We also show that increased camp activity (either size or age) has led to more ornamental species, while, with the notable exception of Skukuza, camp activity has had a much smaller effect on the number of noncultivated species. Noncultivated species tend to be naturally dispersed, as opposed to directly spread by humans between camps. Past management prioritized certain species on the basis of their potential to invade KNP and on the prevailing national legislation. These species were removed manually and follow-up control was carried out. Once the priority species were deemed to be under control, less invasive species were targeted. All alien species were removed from vacated houses, regardless of the potential invasiveness of the species. Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   
80.
ABSTRACT: A model was developed of the periodic-stochastic structure of daily precipitation over an area. The model is based ona multivariate normal distribution. The square roots of daily precipitation at a point were found to approximate a sample from a univariate normal distribution that had been truncated at zero. The zero daily precipitation amounts were considered negative amounts of unknown quantity. The multivariate normal distribution was used to describe the variation of daily precipitation over an area. The periodic fluctuations of the model parameters were described with Fourier series. The model was tested using data from two areas of different precipitation characteristics. Data generated with the model contained many of the statistical characteristics observed in the historical data.  相似文献   
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