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1.
The Baltic Sea Action Plan (BSAP) requires tools to simulate effects and costs of various nutrient abatement strategies. Hierarchically connected databases and models of the entire catchment have been created to allow decision makers to view scenarios via the decision support system NEST. Increased intensity in agriculture in transient countries would result in increased nutrient loads to the Baltic Sea, particularly from Poland, the Baltic States, and Russia. Nutrient retentions are high, which means that the nutrient reduction goals of 135 000 tons N and 15 000 tons P, as formulated in the BSAP from 2007, correspond to a reduction in nutrient loadings to watersheds by 675 000 tons N and 158 000 tons P. A cost-minimization model was used to allocate nutrient reductions to measures and countries where the costs for reducing loads are low. The minimum annual cost to meet BSAP basin targets is estimated to 4.7 billion €.  相似文献   
2.
Hasselquist  Eliza Maher  Mancheva  Irina  Eckerberg  Katarina  Laudon  Hjalmar 《Ambio》2020,49(7):1341-1351
Ambio - Improving water quality has become an important environmental issue, spurred in part by the Water Framework Directive. However, the relationship of policy change with forest water...  相似文献   
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The contamination of food and feed by mycotoxins as toxic metabolites of fungi is a risk not only for consumers resulting in various embarrassment regarding health status and well-being, but also for producers, companies and export market on the ground of economic losses and ruined stability of economic trade. As it is given in historical evidence, the contamination of food by mycotoxins is a topic as old as a history of mankind, finding some evidence even in the ancient books and records. Nowadays, the mycotoxins are used in modern biotechnological laboratories and are considered an agent for targeting the specific cells (e.g., defected cells to eliminate them). However, this promising procedure is only the beginning. More concern is focused on mycotoxins as abiotic hazard agents. The dealing with them, systematic monitoring, and development of techniques for their elimination from agricultural commodities are worldwide issues concerning all countries. They can be found alone or in co-occurrence with other mycotoxins. Thus, this review aims to provide widened information regarding mycotoxins contamination in environment with the consequences on health of animals and humans. The inevitability for more data that correctly determine the risk points linked to mycotoxins occurrence and their specific reactions in the environment is demonstrated. This review includes various symptoms in animals and humans that result from mycotoxin exposure. For better understanding of mycotoxin's impact on animals, the sensitivities of various animal species to various mycotoxins are listed. Strategies for elimination and preventing the risks of mycotoxins contamination as well as economical approach are discussed. To complete the topic, some data from past as historical evidences are presented.  相似文献   
5.
Noise annoyance is influenced by sound-related factors: type of noise, noise level and frequency, and person-related factors—physiological, psychological, and social factors. Prior to implementation of the Directive 2002/49/EC of the European Parliament and of the Council in Serbia, there was a need for the first comprehensive study on noise annoyance in Serbian urban population. The aim of this study was to determine principal factors for high noise annoyance in an adult urban population and to assess their predictive value. A cross-sectional study was performed on 3097 adult residents of a downtown municipality in Belgrade (1217 men and 1880 women), aged 18–96 years. Equivalent noise levels [Leq (dBA)] were measured during day, evening and night in all streets of the municipality. Noise annoyance was estimated using self-reported annoyance scale. Noise annoyance showed strong correlation with noise levels, personal characteristics and some housing conditions. Dose–response relationship was found between the percentage of highly annoyed residents and Lden. Logistic regression model identified increased risk for a high level of noise annoyance with regard to: orientation of living room/bedroom toward the street (Odds Ratio = 2.60; 95% Confidence Interval = 2.04–3.31), duration of stay at apartment during the day [OR = 1.04, 95%CI = 1.02–1.06 (per hour)], noise sensitivity [OR = 1.04, 95%CI = 1.03–1.04 (per scale unit)], and nighttime road-traffic noise level [OR = 1.03, 95%CI = 1.02–1.04 (per decibel)].  相似文献   
6.
Field symptoms typical of ozone injury have been observed on several conifer species in Great Smoky Mountains National Park, and tropospheric ozone levels in the Park can be high, suggesting that ozone may be causing growth impairment of these plants. The objective of this research was to test the ozone sensitivity of selected conifer species under controlled exposure conditions. Seedlings of three species of conifers, Table Mountain pine (Pinus pungens), Virginia pine (Pinus virginiana), and eastern hemlock (Tsuga canadensis), were exposed to various levels of ozone in open-top chambers for one to three seasons in Great Smoky Mountains National Park in Tennessee, USA. A combination of episodic profiles (1988) and modified ambient exposure regimes (1989-92) were used. Episodic profiles simulated an average 7-day period from a monitoring station in the Park. Treatments used in 1988 were: charcoal-filtered (CF), 1.0x ambient, 2.0x ambient, and ambient air-no chamber (AA). In 1989 a 1.5x ambient treatment was added, and in 1990, additional chambers were made available, allowing a 0.5x ambient treatment to be added. Height, diameter, and foliar injury were measured most years. Exposures were 3 years for Table Mountain pine (1988-90), 3 years for hemlock (1989-91), and 1 and 2 years for three different sets of Virginia pine (1990, 1990-91, and 1992). There were no significant (p<0.05) effects of ozone on any biomass fraction for any of the species, except for older needles in Table Mountain and Virginia pine, which decreased with ozone exposure. There were also no changes in biomass allocation patterns among species due to ozone exposure, except for Virginia pine in 1990, which showed an increase in the root:shoot ratio. There was foliar injury (chlorotic mottling) in the higher two treatments (1.0x and 2.0x for Table Mountain and 2.0x for Virginia pine), but high plant-to-plant variability obscured formal statistical significance in many cases. We conclude, at least for growth in the short-term, that seedlings of these three conifer species are insensitive to ambient and elevated levels of ozone, and that current levels of ozone in the Park are probably having minimal impacts on these particular species.  相似文献   
7.

Purpose  

Polychlorinated biphenyls (PCBs) represent a large group of recalcitrant environmental pollutants, differing in the number of chlorine atoms bound to biphenyl ring. Due to their excellent technological properties, PCBs were used as heat-transfer media, for filling transformers and condensers, as paint additives, etc. With increasing knowledge of their toxicity, transfer to food chains and accumulation in living organisms, their production ended in most countries in the 1970s and in 1984 in the former Czechoslovakia. But even a quarter of century after the PCB production ceased, from contaminated areas, the volatile PCBs evaporate and contaminate much larger areas even at very distant parts of the world. For this reason, PCBs still represent a global problem. The main method of PCB removal from contaminated environment is at present the expensive incineration at high temperatures. With the aim of finding effective alternative approaches, we are studying biological methods for PCB removal from the environment. In this paper, we summarise 10 years of studies using long-term PCB-contaminated soil from a dumpsite in South Bohemia, targeted for the use of plants (phytoremediation) and their cooperation with microorganisms in the root zone (rhizoremediation).  相似文献   
8.
Since more than 30 years, the Swedish government as well as other governments in the drainage basin strives toward a reduction in nutrient loads to Baltic Sea coastal waters in order to combat eutrophication of the sea. In spite of this, the cost-effectiveness of actual environmental policy for meeting Baltic Sea nutrient targets has not been evaluated by national or international bodies in the region. The aim of this paper is to evaluate Swedish national nitrogen and phosphorus policies with regard to cost-effectiveness. This is done through a comparison of nutrient measures implemented through environmental policy decisions 1995–2005 with cost-effective policies for present national as well as Baltic Sea Action Plan (BSAP) targets. The cost-effective measures are calculated using an empirical programming model including all countries adjacent to the Baltic Sea. Calculations show that measures that jointly reduce nitrogen and phosphorus are hardly applied in actual policy and that reductions in the agricultural sector are much smaller than is cost-effective. Data show, surprisingly, that considerable reductions have been carried out in the Bothnian Sea catchment in spite of there being no nutrient reduction target for this catchment. Results suggest also that the Swedish costs for meeting the new and geographically more restricted targets under the BSAP can be reduced if a policy with less restrictions on the location of phosphorus abatement is applied, compared to what is now suggested.  相似文献   
9.
The objective of a long-term soil survey is to determine the mean concentrations of several chemical parameters for the pre-defined soil layers and to compare them with the corresponding values in the past. A two-stage random sampling procedure is used to achieve this goal. In the first step, n subplots are selected from N subplots by simple random sampling without replacement; in the second step, m sampling sites are chosen within each of the n selected subplots. Thus n · m soil samples are collected for each soil layer. The idea of the composite sample design comes from the challenge of reducing very expensive laboratory analyses: m laboratory samples from one subplot and one soil layer are physically mixed to form a composite sample. From each of the n selected subplots, one composite sample per soil layer is analyzed in the laboratory, thus n per soil layer in total. In this paper we show that the cost is reduced by the factor m — 1 when instead of the two-stage sampling its composite sample alternative is used; however, the variance of the composite sample mean is increased. In the case of positive intraclass correlation the increase is less than 12.5%; in the case of negative intraclass correlation the increase depends on the properties of the variable as well. For the univariate case we derive the optimal number of subplots and sampling sites. A case study is discussed at the end.  相似文献   
10.
Abstract

Isoquercitrin is a dietary bioflavonoid used as a food supplement. We studied the mechanism underlying its effect in human ovarian cancer cells using OVCAR-3 cell line. Viability, survival, apoptosis, release of human transforming growth factor-β1 (TGF-β1) and TGF-β1 receptor, and intracellular reactive oxygen species (ROS) generation by OVCAR-3 cells were examined after isoquercitrin treatment at concentrations 5, 10, 25, 50, and 100?μg mL?1. AlamarBlue assay revealed that isoquercitrin did not cause any significant change (P?>?0.05) in cell viability as compared to control. Apoptotic assay using flow cytometry did not find any significant change (P?>?0.05) in the proportion of live, dead and apoptotic cells as compared to control. ELISA also showed that the release of human TGF-β1 and TGF-β1 receptor were not significantly (P?>?0.05) affected by isoquercitrin as compared to control. Chemiluminescence assay demonstrated that lower concentrations (5, 10, and 25?μg mL?1) were able to exhibit beneficial effects by inhibiting the generation of intracellular ROS. In contrast, elevated concentrations of 50 and 100?μg mL?1 led to oxidative stress (P?相似文献   
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