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251.
The effect of both increased concentrations (0.01 and 1 mg l(-1)) of fluoranthene (FLT) and the duration of exposure (18 and 25 days) on the growth and photosynthetic processes in pea plants (Pisum sativum L., cv. Garde) was investigated. FLT concentration in roots and shoot of pea plants was also determined. The obtained results demonstrated that the higher concentration of FLT (1 mg l(-1)) significantly inhibited the growth of the pea plants after 25 days of the application, also affected the content of photosynthetic pigments (chlorophyll a, b and carotenoids), and the primary photochemical processes of photosynthesis. In chlorophyll fluorescence parameters, the significant increase of F(0) values and the decrease of F(V)/F(M) and Phi(II) values was recorded. The Hill reaction of isolated chloroplasts of pea plants was significantly inhibited after 25 days by presence of FLT (0.01 and 1 mg l(-1)) in nutrient solution, while after 18 days no significant response of Hill reaction activity was recorded. The fluoranthene content in roots and shoot of pea plants increased with increasing FLT concentration in the environment and the substantial accumulation of FLT was observed in the roots.  相似文献   
252.
Tront JM  Saunders FM 《Chemosphere》2006,64(3):400-407
Aquatic plants uptake, transform and sequester organic contaminants and are used as a bioremediation strategy for the removal of pollutants from wastewaters. A better understanding of factors affecting rate of uptake of contaminants by aquatic plants is needed to improve engineered systems for removal of pollutants from wastewaters. This work focused on delineating sorption to plant surfaces and understanding effects of plant metabolic activity, inhibition, and media pH on the uptake of the ionizable contaminant 2,4,5-trichlorophenol (TCP) by aquatic plant Lemna minor. During L. minor exposure to TCP (0.5-13.9 mg l(-1)), a range of plant metabolic activities was measured using oxygen production rate (0-18.4 micromol h(-1)). A positive correlation was shown between contaminant uptake rate and plant activity. Contaminant uptake was examined at a range of media pH values (6-9) and uptake rates were linearly correlated to fraction of contaminant in protonated form. These results demonstrated a link between plant activity and uptake of contaminant by plants and stress the importance of incorporating plant metabolic activity and contaminant speciation in development of natural and engineered phytoremediation systems. This research also indicates that aquatic plants can actively accumulate trace-organic contaminants and may ultimately serve as a sink for these materials in the natural environment.  相似文献   
253.
Host plant odours attract gravid insect females for oviposition. The identification of these plant volatile compounds is essential for our understanding of plant–insect relationships and contributes to plant breeding for improved resistance against insects. Chemical analysis of grape headspace and subsequent behavioural studies in the wind tunnel show that host finding in grapevine moth Lobesia botrana is encoded by a ratio-specific blend of three ubiquitous plant volatiles. The odour signal that attracts mated females to grape consists of the terpenoids (E)-β-caryophyllene, (E)-β-farnesene and (E)-4,8-dimethyl-1,3,7-nonatriene. These compounds represent only a fraction of the volatiles released by grapes, and they are widespread compounds known throughout the plant kingdom. Specificity may be achieved by the blend ratio, which was 100:78:9 in grape headspace. This blend elicited anemotactic behaviour in moths at remarkably small amounts. Females were attracted at release rates of only a few nanograms per minute, at levels nearly as low as those known for the attraction of male moths to the female sex pheromones.  相似文献   
254.
255.
This paper takes a first step in comparing and synthesising the emerging concept of energy justice with extant ethical consumption literatures as two complementary theoretical approaches to ethics and consumption. To date, theories of ethical consumption and energy justice remain somewhat disconnected, so while they have some areas of potential comparability, these have not yet been fleshed out or developed. To address this lacuna, this paper explores areas where research into ethical consumption might be useful for furthering concepts of energy justice. More specifically the discussion draws on the philosophical foundations, the relationship between consumption and development, and the role of transparency and visibility in reconnecting consumption and production practices as the main areas of overlap in these literatures. The conclusion points to some lessons for emerging energy justice literatures that can be drawn from this task of comparison and synthesis.  相似文献   
256.
沿海经济活动的发展与海洋/沿海环境之间的关系异常脆弱.但凡工业扩张的地方,海洋/沿海的生态系统就总体恶化.土地污染引发大量危害.对于旅游产业,特别是在岛屿地区,环境的危害必然会削弱这个产业."全球从陆地活动保护海洋环境的行动计划"谋求改变这种关系.它提出一个有效掌控陆地污染物的计划.未来的落实倚重合作伙伴,特别是私人部门发起或参与的行动.  相似文献   
257.
Degradation and mobility of the surfactants linear alkylbenzene sulfonate (LAS) and nonylphenol (NP) were investigated in a lysimeter study using a sandy loam soil and 45-cm soil columns. Anaerobically digested sewage sludge was incorporated in the top-15-cm soil layer to an initial content of 38 mg LAS and 0.56 mg NP kg(-1) dry wt., respectively. Spring barley (Hordeum vulgare L.) was sown onto the columns. The lysimeters were placed outdoors and therefore received natural precipitation, but were also irrigated to a total amount of water equivalent to 700 mm of precipitation. Leachate and soil samples from three soil layers were collected continuously during a growth period of 110 d. Leachate samples and soil extracts were concentrated by solid-phase extraction (SPE) and analyzed using high performance liquid chromatography (HPLC) with fluorescence detection. The concentrations in the top-15-cm soil layer declined to 25 and 45% of the initial contents for LAS and NP, respectively, within the first 10 d of the study. At the end of the study, less than 1% LAS was left, while the NP content was below the detection limit. Assuming first-order degradation kinetics, half-lives of 20 and 37 d were estimated for LAS and NP, respectively. The surfactants were not measured in leachate samples in concentrations above the analytical detection limits of 4.0 and 0.5 microg L(-1) for LAS and NP, respectively. In addition, neither LAS nor NP were measured in concentrations above the detection limits of 150 and 50 microg kg(-1) dry wt., respectively, in soil layers below the 15 cm of sludge incorporation, indicating negligible downward transport of the surfactants in the lysimeters.  相似文献   
258.
Pesticide uses and transfers in urbanised catchments   总被引:1,自引:0,他引:1  
An investigation on herbicide uses in two semi-urban catchments was performed simultaneously with sampling campaigns at six stations inside both watersheds from April to July 1998. Urban uses of herbicides exceeded agricultural uses, and transfer coefficients were also higher in urban areas. Therefore, the most used product in urban areas (diuron) was by far the most contaminating product. Householders accounted for 30% of all uses. The highest measured diuron concentration in water surface was 8.7 microg l(-1) due to its use on impervious surfaces. Compared to EEC standards for drinking water production (0.1 microg l(-1)), it is clear that suburban uses of herbicides may severely endanger drinking water production from river water.  相似文献   
259.
After satisfying their quantitative and qualitative needs as regards nutrition, consumers in developed countries are becoming more involved in the ethical aspects of food production, especially when it relates to animal products. Social demands for respecting animal welfare in housing systems are increasing rapidly, as is social awareness of human responsibility towards farm animals. Many studies have been conducted on animal welfare measurement in different production systems, but the available information for small ruminants remains insufficient. In this study, a 75 criteria-evaluation tool has been set up on the basis of the five freedoms concept. Animal welfare considerations have been analyzed in 25 documents, including labeling schemes, regulations, and recommendations from different European countries. The results show many differences between regular and organic small ruminant farming standards. Emergency measures are generally lacking. A weak representation of psychological aspects of animal welfare, especially by the current European legislation, is highlighted.  相似文献   
260.
The aim of this study is to explore the manner in which different measures of original socioeconomic position (SEP) influence road traffic injuries (RTIs) among young car drivers in Sweden. The study consists of young people age 16-23. Subjects were taken from the Swedish Population and Housing Census of 1990 (n=727,995), and followed up by a search for cases of injury to car drivers in Sweden's National Hospital Discharge Register over the years 1991-96 (n=1,599). Household SEP was measured using social class, education, and disposable income. Relative risks were estimated by Poisson regression and population attributable risks were computed for each measure of SEP. Children of unskilled workers, of the self-employed, and of farmers, as well as children of parents with compulsory education only showed an increased risk of injury as car drivers compared to children in the highest socioeconomic group and children of highly educated parents. By contrast, level of household disposable income was found not to vary with RTI among young drivers. Twenty-five percent of the injuries could be avoided if all young people had the injury rate of the highest socioeconomic group, and 29% if all young people had the injury rate of those with highly educated parents. The reduction of risk differences based on household SEP calls for consideration of factors related to both differential exposure and differential susceptibility, which may be addressed in driver education.  相似文献   
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