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161.
In recent years, fuzzy-logic-based methods have demonstrated to be appropriated to address uncertainty and subjectivity in environmental problems. In the present study, a methodology based on fuzzy inference systems (FIS) to assess water quality is proposed. A water quality index calculated with fuzzy reasoning has been developed. The relative importance of water quality indicators involved in the fuzzy inference process has been dealt with a multi-attribute decision-aiding method. The potential application of the fuzzy index has been tested with a case study. A data set collected from the Ebro River (Spain) by two different environmental protection agencies has been used. The current findings, managed within a geographic information system, clearly agree with official reports and expert opinions about the pollution problems in the studied area. Therefore, this methodology emerges as a suitable and alternative tool to be used in developing effective water management plans.  相似文献   
162.
Regional Environmental Change - Plausible scenarios of future land use derived from model projections may differ substantially from what is actually desired by society, and identifying such...  相似文献   
163.

The continuously growing global demands on a finite land resource will require better strategic policies and management of trade-offs to avoid conflicts between different land-use sectors. Visions of the future can support strategic planning by stimulating dialogue, building a consensus on shared priorities and providing long-term targets. We present a novel approach to elicit stakeholder visions of future desired land use, which was applied with a broad range of experts to develop cross-sectoral visions in Europe. The approach is based on (i) combination of software tools and facilitation techniques to stimulate engagement and creativity; (ii) methodical selection of stakeholders; (iii) use of land attributes to deconstruct the multifaceted sectoral visions into land-use changes that can be clustered into few cross-sectoral visions, and (iv) a rigorous iterative process. Three cross-sectoral visions of sustainable land use in Europe in 2040 emerged from applying the approach in participatory workshops involving experts in nature conservation, recreation, agriculture, forestry, settlements, energy, and water. The three visions—Best Land in Europe, Regional Connected and Local Multifunctional—shared a wish to achieve a land use that is sustainable through multifunctionality, resource use efficiency, controlled urban growth, rural renewal and widespread nature. However, they differ on the scale at which land services are provided—EU-wide, regional or local—reflecting the land-sparing versus land-sharing debate. We discuss the usefulness of the approach, as well as the challenges posed and solutions offered by the visions to support strategic land-use planning.

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164.
Environmental Science and Pollution Research - Recycled aggregates (RA) from construction and demolition waste (CDW) instead of natural aggregates (NA) were analysed in the manufacture of new...  相似文献   
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167.
Pyrene degradation by yeasts and filamentous fungi   总被引:8,自引:0,他引:8  
The saprotrophic soil fungi Fusarium solani (Mart.) Sacc., Cylindrocarpon didymum (Hartig) Wollenw, Penicillium variabile Sopp. and the yeasts Rhodotorula glutinis (Fresenius) Harrison and Rhodotorula minuta (Saito) Harrison were cultured in mineral medium with pyrene. The remaining pyrene concentrations were periodically determined during 20 incubation days, using HPLC. To assess the metabolism of pyrene degradation we added 0.1 microCi of [4,5,9,10] 14C-pyrene to each fungi culture and measured the radioactivity in the volatile organic substances, extractable, aqueous phase, biomass and 14CO2 fractions. The assays demonstrated that F. solani and R. glutinis metabolized pyrene as a sole source of carbon. Differences in their activities at the beginning of the cultures disappeared by the end of the experiment, when 32 and 37% of the original pyrene concentration was detected, for the soil fungi and yeasts, respectively. Among the filamentous fungi, F. solani was highly active and oxidized pyrene; moreover, small but significant degradation rates were observed in C. didymum and P. variahile cultures. An increase in the 14CO2 evolution was observed at the 17th day with cosubstrate. R. glutinis and R. minuta cultures showed similar ability to biotransform pyrene, and that 35% of the initial concentration was consumed at the end of the assay. The same results were obtained in the experiments with or without glucose as cosubstrate.  相似文献   
168.
Photodegradation of an azo dye of the textile industry   总被引:2,自引:0,他引:2  
An advanced oxidation treatment, UV/H2O2, was applied to an azo dye, Hispamin Black CA, widely used in the Peruvian textile industry. Rates of color removal and degradation of the dye have been evaluated. A strongly absorbing solution was completely decolorized after 35 min of treatment, and after 60 min an 82% reduction of the total organic carbon (TOC) was obtained. It has been found that the degradation rate increased until an optimum value, beyond which the reagent exerted an inhibitory effect. The degradation rate was also function of pH.  相似文献   
169.
Green lacewings in the carnea group of Chrysoperla engage in species-specific heterosexual duets using low-frequency substrate-borne signals. Within each species, both sexes sing nearly identical songs. Songs are the principal barriers to hybridization between sympatric species in the complex. Here, we investigated the responsiveness of males and females of Chrysoperla plorabunda to synthesized, prerecorded songs that differed from the species mean in the period between repeated volleys of abdominal vibration. We tested 15–16 males and 15–16 females using playbacks of two signals that gradually increased or decreased in volley period, starting at the species mean. We found that (1) duets during courtship are accurate, interactive, and adjustable by each participant; (2) in staged duets, both sexes respond best to song tempos near the mean volley period of their population, but can nonetheless maintain duets with signals of nearly twice, or half, the normal volley period; (3) individuals fine-tune their adjustments to signals of different volley periods by changing their own volley duration and latent period, or less often by inserting extra volleys or skipping every other volley; (4) males are significantly better at matching signals of changing tempo than females; and (5) the range of song responsiveness of C. plorabunda does not overlap the natural range of volley periods found in Chrysoperla adamsi, an acoustically similar sibling species, thus reaffirming strong behavioral isolation. In sum, the precise, almost unbreakable heterosexual duets characteristic of song species of the carnea group result from tight mutual feedback between partners. Effective reproductive isolation between species can be based on song differences alone.  相似文献   
170.
In the present study, the effects of differing salinities on some important functional responses of haemocytes from the clam, Chamelea gallina, were investigated. The animals were kept for 7 days at 28‰ (hyposalinity), 34‰ (control) and 40‰ salinity (hypersalinity), and total haemocyte count (THC), haemocyte volume, phagocytosis, lysozyme-like activity (in both haemocyte lysate and cell-free haemolymph) were measured. The survival-in-air test was also performed. Clams kept at 28‰ showed significantly increased THC with respect to animals kept at 34 and 40‰. The analysis of haemocyte size frequency distribution highlighted that in clams kept at 28‰ the haemocyte fraction of about 5 μm in diameter and 50–100 femtolitre in volume increased markedly. Conversely, in animals kept at 40‰ an increase was observed in the haemocyte fraction having about 8–10 μm diameter and 400–500 femtolitre volume. Higher phagocytic activity was recorded in haemocytes from control clams, with respect to that of clams kept at 28 and 34‰. Lysozyme-like activity in haemocyte lysate was shown to increase significantly in animals kept at 28‰ with respect to that of clams kept at 40‰, whereas enzyme activity in cell-free haemolymph from clams kept at 34‰ was significantly higher with respect to that of clams maintained at 40‰. A relationship between phagocytosis and lysozyme secretion is suggested. The resistance to air exposure of clams kept at 28 and 40‰ was shown to decrease significantly; LT50 values fell from 7 days in clams kept at 34‰ to 4 and 5 days in those kept at 28 and 40‰, respectively. Results demonstrated that salinity values far from 34‰ affects the functional responses of haemocytes and reduce the resistance of clams to exposure to air.  相似文献   
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