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181.
Various measures of plants, soils, and invertebrates were described for a reference set of tidal coastal wetlands in Southern New England in order to provide a framework for assessing the condition of other similar wetlands in the region. The condition of the ten coastal wetlands with similar hydrology and geomorphology were ranked from least altered to highly altered using a combination of statistical methods and best professional judgment. Variables of plants, soils, and invertebrates were examined separately using principal component analysis to reduce the multidimensional variables to principal component scores. The first principal component scores of each set of variables (i.e., plants, soil, invertebrates) significantly (p?<?0.05) correlated with both residential land use and watershed nitrogen (N) loads. Using cumulative frequency diagrams, the first principal component scores of each plant, soil, and invertebrate data set were plotted, and natural breaks and best professional judgment were used to rank the first principal component scores among the sites. We weighted all three ranked components equally and calculated an overall salt marsh condition index by summing the three ranks and then transforming the index to a 0–1 scale. The overall salt marsh condition index for the reference coastal wetland set significantly correlated with the residential land use (R?=???0.87, p?=?0.001) and watershed N loads (R?=???0.86, p?=?0.001). Overall, condition deteriorated in salt marshes and their associated discharge streams when subjected to increasing watershed residential land use and N loads.  相似文献   
182.
Tokyo has historically suffered from a shortage of final disposal sites for the treated sewage sludge. Given this situation, sludge recycling and incineration have been promoted to reduce the volume of treated sludge conveyed to the disposal site, and the recycling options have changed since the late 1990s. This study aims to revisit the sewage sludge treatment and recycling processes in Tokyo and to evaluate different recycling options (brick, aggregate, refuse derived fuel and slag) from the energy consumption perspective by clarifying the complex flow of treated sludge within Tokyo's 23 wards. The study also estimates environmental loads associated with the operation of the whole sludge management system in the area. The environmental loads include: (1) total energy consumption and (2) gas emissions (greenhouse and acidification gases). The estimation was carried out for the years 1995, 1997, 1999 and 2001, during which a drastic change in recycling options occurred. The results indicated that the production of refuse derived fuel was the most energy consuming recycling option while aggregate production is the least energy consuming. They also showed that despite the increasing sludge volume, the energy consumption associated with the operation of the whole system decreased during the period while the gas emissions increased.  相似文献   
183.
Agricultural wastes such as lignocellulosic residues are renewable resources can be used for mushroom cultivation. Spent mushroom substrate (SMS) is defined as leftover of biomass generated by commercial mushroom industries after harvesting period of mushroom. Mushroom cultivation using agricultural wastes promises a good quality of SMS for producing beneficial products such as animal feeding and fertilizers. Based on the published papers, the major applications of SMS are animal feedstock, fertilizer, energy production and wastewater treatment. For instance, some species of mushroom such as Pleurotus spp. and Agaricus bisporus are suitable for applications of ruminant feedstock and fertilizers. This paper reviews the recent studies about the beneficial usage of SMS which is considered as a waste since 2013.  相似文献   
184.
Research on trace elements and the effects of their ingestion on human health is often seen in scientific literature. However, little research has been done on the distribution of trace elements in the environment and their impact on health. This paper examines what characteristics among participants in the Reasons for Geographic and Racial Differences in Stroke (REGARDS) study are associated with levels of environmental exposure to arsenic, magnesium, mercury, and selenium. Demographic information from REGARDS participants was combined with trace element concentration data from the US Geochemical Survey (USGS). Each trace element was characterized as either low (magnesium and selenium) or high (arsenic and mercury) exposure. Associations between demographic characteristics and trace element concentrations were analyzed with unadjusted and adjusted logistic regression models. Individuals who reside in the Stroke Belt have lower odds of high exposure (4th quartile) to arsenic (OR 0.33, CI 0.31, 0.35) and increased exposure to mercury (OR 0.65, CI 0.62, 0.70) than those living outside of these areas, while the odds of low exposure to trace element concentrations were increased for magnesium (OR 5.48, CI 5.05, 5.95) and selenium (OR 2.37, CI 2.22, 2.54). We found an association between levels of trace elements in the environment and geographic region of residence, among other factors. Future studies are needed to further examine this association and determine whether or not these differences may be related to geographic variation in disease.  相似文献   
185.
186.
Policies aiming at improving biodiversity often consist of costly agri-environmental schemes, i.e. subsidized grazing or mowing of semi-natural areas. However, these practices have widely been found to be insufficient to mitigate biodiversity loss. Rewilding, i.e. restoring natural processes in self-sustaining biodiverse ecosystems, has been proposed as an alternative and is hypothesized to be a more cost-efficient approach to promote biodiversity conservation. Rewilding requires the availability of large natural areas which are not allocated for farming, forestry, and infrastructure to avoid potential conflicts over the use of the area. We perform an ex-ante private cost–benefit analysis of the establishment of four large nature reserves for rewilding in Denmark. We analyse the economic effects of changing from summer grazing in nature areas in combination with cultivated fields and forestry to the establishment of nature reserves in four case areas. We consider two scenarios involving conversion of agriculture and forestry areas into natural areas in combination with either extensive year-round cattle grazing or rewilding with wild large herbivores. In two case areas, it appears possible to establish large nature areas without incurring extra costs. Additionally, rewilding further reduces costs compared to year-round cattle grazing. Two opposing effects were dominant: increased economic rent occurred from the shift from summer grazing to year-round grazing or rewilding, while cessation of agriculture and forestry caused opportunity costs.  相似文献   
187.
The known chemical basis of diverse avian eggshell coloration is generated by the same two classes of tetrapyrrole pigments in most living birds. We aimed to extend the evolutionary scope of these patterns by detecting pigments from extinct birds’ eggs. In our samples biliverdin was successfully extracted from subfossil shell fragments of the blue-green egg-laying upland moa Megalapteryx didinus, while protoporphyrin was extracted from the beige eggs of two other extinct moa species. Our data on pigment detection from eggshells of other extant paleognath birds, together with published information on other modern lineages, confirm tetrapyrroles as ubiquitous and conserved pigments contributing to diverse eggshell colours throughout avian evolution.  相似文献   
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189.
Atmospheric particulates were monitored on a typical high concentration day in early winter in Osaka, Japan, using a compact and portable eye-safe laser radar system. The height of mixing layer was about 0.4 km at 8:00 and gradually increased to 0.8 km at 14:00. The development of the layer was in inverse proportion to the decrease of particulates near the ground surface. Analysis of particulates collected with high-volume air samplers showed that concentrations of elemental carbon (EC), lead and ammonium ion near the surface decreased significantly from morning to midday, while concentrations of sulfate, nitrate, sodium and calcium ions were almost constant. The results obtained in the preliminary study suggest that anthropogenic particulates such as EC and lead are on the rise with development of mixing layer from morning to midday.  相似文献   
190.
Shellfish samples (n = 310) purchased from local supermarkets were analysed for the presence of hepatitis E virus (HEV) by nested RT-PCR and real-time qRT-PCR. Overall, 2.9% of samples tested positive for the presence of HEV. Phylogenetic analysis of HEV sequences revealed all as being genotype 3 HEV. This is the first report of the detection of HEV in commercially sold shellfish in Scotland. These findings may encourage further research that will help address the gaps in the knowledge in respect to foodborne transmission of HEV in Scotland and the rest of the United Kingdom.  相似文献   
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