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291.
Satisfaction of communities living close to forests with forest management authorities is essential for ensuring continued
support for conservation efforts. However, more often than not, community satisfaction is not systematically elicited, analyzed,
and incorporated in conservation decisions. This study attempts to elicit levels of community satisfaction with three management
approaches of Kakamega forest in Kenya and analyze factors influencing them. Three distinct management approaches are applied
by three different authorities: an incentive-based approach of the Forest Department (FD), a protectionist approach of the
Kenya Wildlife Service (KWS), and a quasi-private incentive-based approach of Quakers Church Mission (QCM). Data was obtained
from a random sample of about 360 households living within a 10-km radius around the forest margin. The protectionist approach
was ranked highest overall for its performance in forest management. Results indicate that households are influenced by different
factors in their ranking of management approaches. Educated households and those located far from market centers are likely
to be dissatisfied with all the three management approaches. The location of the households from the forest margin influences
negatively the satisfaction with the protectionist approach, whereas land size, a proxy for durable assets, has a similar
effect on the private incentive based approach of the QCM. In conclusion, this article indicates a number of policy implications
that can enable the different authorities and their management approaches to gain approval of the local communities. 相似文献
292.
A database of global agricultural primary production has been constructed and used to estimate its energy content. The portion
of crops available for food and biofuel after postharvest losses was evaluated. The basic conditions for agriculture and plant
growth were studied, to ensure sustainable scenarios regarding use of residues. The available energy contents for the world
and EU27 was found to be 7,200–9,300 and 430 TWh, respectively, to be compared with food requirements of 7,100 and 530 TWh.
Clearly, very little, or nothing, remains for biofuel from agricultural primary crops. However, by using residues and bioorganic
waste, it was found that biofuel production could theoretically replace one-fourth of the global consumption of fossil fuels
for transport. The expansion potential for global agriculture is limited by availability of land, water, and energy. A future
decrease in supply of fossil energy and ongoing land degradation will thus cause difficulties for increased biofuel production
from agriculture. 相似文献
293.
A multi-scaled model for biodiversity conservation in forests was introduced in Sweden 30 years ago, which makes it a pioneer
example of an integrated ecosystem approach. Trees are set aside for biodiversity purposes at multiple scale levels varying
from individual trees to areas of thousands of hectares, with landowner responsibility at the lowest level and with increasing
state involvement at higher levels. Ecological theory supports the multi-scaled approach, and retention efforts at every harvest
occasion stimulate landowners’ interest in conservation. We argue that the model has large advantages but that in a future
with intensified forestry and global warming, development based on more progressive thinking is necessary to maintain and
increase biodiversity. Suggestions for the future include joint planning for several forest owners, consideration of cost-effectiveness,
accepting opportunistic work models, adjusting retention levels to stand and landscape composition, introduction of temporary
reserves, creation of “receiver habitats” for species escaping climate change, and protection of young forests. 相似文献
294.
Karin Löfstrand Anna Malmvärn Peter Haglund Anders Bignert Åke Bergman Lillemor Asplund 《Environmental science and pollution research international》2010,17(8):1460-1468
Introduction
Naturally occurring hydroxylated polybrominated diphenyl ethers (OH-PBDEs), their methoxylated counterparts (MeO-PBDEs), and polybrominated dibenzo-p-dioxins (PBDDs), together with their potential precursors polybrominated phenols (PBPs) and polybrominated anisoles (PBAs), were analyzed in blue mussels (Mytilus edulis) gathered along the east coast (bordering the Baltic Sea) and west coast of Sweden (bordering the North Sea). Brown algae (Dictyosiphon foenicolaceus) and cyanobacteria (Nodularia spumigena) from the Baltic Sea, considered to be among the primary producers of these compounds, were also analyzed for comparison. 相似文献295.
Maurice C Gustavsson B Ragnvaldsson D Rydvall B Berglind R Haglund P Johnson T Leffler P Luthbom K von Heijne P 《Ambio》2007,36(6):502-511
Investigations of polluted brownfield sites and sample analyses are expensive, and the resulting data are often of poor quality. Efforts are needed, therefore, to improve the methods used in investigations of brownfield sites to both reduce costs and improve the quality of the results. One approach that could be useful for both of these purposes is the triad strategy, developed by the US Environmental Protection Agency, in which managing uncertainty is a central feature. In the investigations reported here, a field study was conducted to identify possible ways in which uncertainties could be managed in practice. One example considered involves optimizing the uncertainty by adjusting the sizes of samples and the efforts expended in analytical work according to the specific aims of the project. In addition, the potential utility of several toxicity assessment methods for screening sites was evaluated. As well as presenting the results of these assessments, in this contribution we discuss ways in which a flexible work strategy and screening methods inspired of the triad philosophy could be incorporated into the Swedish approach to remediate brownfield sites. A tiered approach taking advantage of field and screening methods is proposed to assess brownfield sites focusing on the response and acceptable uncertainty that are required for the task. 相似文献
296.
Hwang IH Matsuto T Tanaka N Sasaki Y Tanaami K 《Waste management (New York, N.Y.)》2007,27(9):1155-1166
Carbonization is a kind of pyrolysis process to produce char from organic materials under an inert atmosphere. In this work, chars derived from various solid wastes were characterized from the standpoint of fuel recovery and pretreatment of waste before landfilling. Sixteen kinds of municipal and industrial solid wastes such as residential combustible wastes, non-combustible wastes, bulky wastes, construction and demolition wastes, auto shredder residue, and sludges were carbonized at 500 degrees C for 1h under nitrogen atmosphere. In order to evaluate the quality of char as fuel, proximate analysis and heating value were examined. The composition of raw waste had a significant influence on the quality of produced char. The higher the ratio of woody biomass in waste, the higher heating value of char produced. Moreover, an equation to estimate heating value of char was developed by using the weight fraction of fixed carbon and volatile matter in char. De-ashing and chlorine removal were performed to improve the quality of char. The pulverization and sieving method seems to be effective for separation of incombustibles such as metal rather than ash. Most char met a 0.5 wt% chlorine criterion for utilization as fuel in a shaft blast furnace after it was subjected to repeated water-washing. Carbonization could remove a considerable amount of organic matter from raw waste. In addition, the leaching of heavy metals such as chrome, cadmium, and lead appears to be significantly suppressed by carbonization regardless of the type of raw waste. From these results, carbonization could be considered as a pretreatment method for waste before landfilling, as well as for fuel recovery. 相似文献
297.
Remediation of cadmium-contaminated paddy soils by washing with calcium chloride: verification of on-site washing 总被引:2,自引:0,他引:2
Makino T Kamiya T Takano H Itou T Sekiya N Sasaki K Maejima Y Sugahara K 《Environmental pollution (Barking, Essex : 1987)》2007,147(1):112-119
We developed a new, three-step soil-wash method to remediate Cd-contaminated paddy fields. The method comprises (1) chemically washing the field soil with a CaCl2 solution; (2) washing the treated soil with water to eliminate residual Cd and CaCl2; and (3) on-site treatment of wastewater using a portable wastewater treatment system. Cd concentrations in the treated water were below Japan's environmental quality standard (0.01 mg Cd L-1), and the removal of Cd from the exchangeable fraction was 55% and from the acid-soluble fraction 15%. While soil fertility properties were affected by the soil washing, adverse effects were not crucial and could be corrected. The washing had no affect on rice growth, and reduced the average Cd concentration in rice grains by about two-thirds compared to a control plot. These results confirmed the effectiveness of the soil-wash method in remediating Cd-contaminated paddy fields. 相似文献
298.
Per StÅlnacke Anders Grimvall Karin Sundblad Andrzej Tonderski 《Environmental monitoring and assessment》1999,58(2):173-200
This article presents the results of the first critical examination of time series of riverine nutrient-load data for the entire Baltic Sea drainage area. Water quality data collected by or for the different national environmental agencies were compiled and analysed statistically to identify and remove inconsistent or obviously incorrect observations. Moreover, sampling tours were undertaken to acquire additional information about the present nutrient concentrations in the largest rivers in the study area. Gaps in the time series of approved data were then filled in by employing statistical interpolation and extrapolation methods. Thereafter, the concentration and runoff data were combined to obtain estimates of monthly nutrient loads for the time period 1970–93. The results of the calculations showed that although there had been substantial changes in land use, atmospheric deposition and wastewater treatment in many parts of the study area, the total riverine loads of nitrogen (N) and phosphorus (P) to the Baltic Sea have been fairly constant since 1980, and most likely also since 1970. Moreover, the interannual variation was clearly correlated to the runoff. The mean annual loads for the time period 1980–93 were found to be about 825 000 tonnes N and 41 000 tonnes P, respectively. This implies that (i) several other investigators have strongly underestimated the riverine loads of nutrients, especially the nitrogen, and that (ii) the riverine loads by far exceed the input to the Baltic Sea from other sources, {i.e.} atmospheric deposition, direct emissions from cities and industries along the Baltic Sea coast and nitrogen fixation by marine algae. 相似文献
299.
Okada Kensuke Suzaki Yû Sasaki Rikiya Katsuki Masako 《Behavioral ecology and sociobiology》2017,71(5):1-11
Behavioral Ecology and Sociobiology - Close behavioural association between mothers and offspring should enhance survival and growth of the young. Eastern grey kangaroos Macropus giganteus are... 相似文献