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John Hahladakis Eleftheria Smaragdaki Georgia Vasilaki Evangelos Gidarakos 《Environmental monitoring and assessment》2013,185(3):2843-2853
Eight different surface sediment samples (K1–K8) were collected from two separate areas of Lake Koumoundourou and two samples (E1 and E2) from one area of Elefsis Bay, Athens, Greece. The level of pollution attributed to heavy metals was evaluated using several pollution indicators. Degree of Contamination, Modified Contamination Degree and Geoaccumulation Indexes were applied in order to determine and assess the anthropogenic contribution of the selected six elements (Cr, Ni, Cu, Zn, As and Pb). Moreover, the adverse effects of the sediments to aquatic organisms, from both heavy metals and polycyclic aromatic hydrocarbons (PAHs), were determined by using Sediment Quality Guidelines. The results indicated that Lake Koumoundourou is contaminated with heavy metals in a moderate degree and almost 50 % of the sediments are associated with frequent observation of adverse effects, when it comes to Ni and occasional observation of adverse effects, when it comes to Cu, Zn and Pb. As far as PAHs are concerned, around 60 % of the samples can be occasionally associated to toxic biological effects according to the effect-range classification for phenanthrene, benzo(a)anthracene, chrysene and pyrene. Finally, samples taken from the north side of the lake are more contaminated with PAHs than the ones taken from the east side probably due to the existence of the water barrier which acts as a reservoir of PAHs. 相似文献
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Integrating Landscape Ecology and Geoinformatics to Decipher Landscape Dynamics for Regional Planning 总被引:1,自引:0,他引:1
We used remote sensing and GIS in conjunction with multivariate statistical methods to: (i) quantify landscape composition
(land cover types) and configuration (patch density, diversity, fractal dimension, contagion) for five coastal watersheds
of Kalloni gulf, Lesvos Island, Greece, in 1945, 1960, 1971, 1990 and 2002/2003, (ii) evaluate the relative importance of
physical (slope, geologic substrate, stream order) and human (road network, population density) variables on landscape composition
and configuration, and (iii) characterize processes that led to land cover changes through land cover transitions between
these five successive periods in time. Distributions of land cover types did not differ among the five time periods at the
five watersheds studied because the largest cumulative changes between 1945 and 2002/2003 did not take place at dominant land
cover types. Landscape composition related primarily to the physical attributes of the landscape. Nevertheless, increase in
population density and the road network were found to increase heterogeneity of the landscape mosaic (patchiness), complexity
of patch shape (fractal dimension), and patch disaggregation (contagion). Increase in road network was also found to increase
landscape diversity due to the creation of new patches. The main processes involved in land cover changes were plough-land
abandonment and ecological succession. Landscape dynamics during the last 50 years corroborate the ecotouristic-agrotouristic
model for regional development to reverse trends in agricultural land abandonment and human population decline and when combined
with hypothetical regulatory approaches could predict how this landscape could develop in the future, thus, providing a valuable
tool to regional planning. 相似文献
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The management of dewatered wastewater sludge is a major issue worldwide. Sludge disposal to landfills is not sustainable and thus alternative treatment techniques are being sought. The objective of this work was to determine optimal mixing ratios of dewatered sludge with other organic amendments in order to maximize the degradability of the mixtures during composting. This objective was achieved using mixture experimental design principles. An additional objective was to study the impact of the initial C/N ratio and moisture contents on the co-composting process of dewatered sludge. The composting process was monitored through measurements of O(2) uptake rates, CO(2) evolution, temperature profile and solids reduction. Eight (8) runs were performed in 100 L insulated air-tight bioreactors under a dynamic air flow regime. The initial mixtures were prepared using dewatered wastewater sludge, mixed paper wastes, food wastes, tree branches and sawdust at various initial C/N ratios and moisture contents. According to empirical modeling, mixtures of sludge and food waste mixtures at 1:1 ratio (ww, wet weight) maximize degradability. Structural amendments should be maintained below 30% to reach thermophilic temperatures. The initial C/N ratio and initial moisture content of the mixture were not found to influence the decomposition process. The bio C/bio N ratio started from around 10, for all runs, decreased during the middle of the process and increased to up to 20 at the end of the process. The solid carbon reduction of the mixtures without the branches ranged from 28% to 62%, whilst solid N reductions ranged from 30% to 63%. Respiratory quotients had a decreasing trend throughout the composting process. 相似文献
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Prenatal diagnosis of achondroplasia presenting with multiple-suture synostosis: a novel association
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Key parameters and practices controlling pesticide degradation efficiency of biobed substrates 总被引:1,自引:0,他引:1
Karanasios E Karpouzas DG Tsiropoulos NG 《Journal of environmental science and health. Part. B》2012,47(6):589-598
We studied the contribution of each of the components of a compost-based biomixture (BX), commonly used in Europe, on pesticide degradation. The impact of other key parameters including pesticide dose, temperature and repeated applications on the degradation of eight pesticides, applied as a mixture, in a BX and a peat-based biomixture (OBX) was compared and contrasted to their degradation in soil. Incubation studies showed that straw was essential in maintaining a high pesticide degradation capacity of the biomixture, whereas compost, when mixed with soil, retarded pesticide degradation. The highest rates of degradation were shown in the biomixture composed of soil/compost/straw suggesting that all three components are essential for maximum biobed performance. Increasing doses prolonged the persistence of most pesticides with biomixtures showing a higher tolerance to high pesticide dose levels compared to soil. Increasing the incubation temperature from 15 °C to 25 °C resulted in lower t(1/2) values, with biomixtures performing better than soil at the lower temperature. Repeated applications led to a decrease in the degradation rates of most pesticides in all the substrates, with the exception of iprodione and metalaxyl. Overall, our results stress the ability of biomixtures to perform better than soil under unfavorable conditions and extreme pesticide dose levels. 相似文献
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Evangelos Karanasios Helen Karasali Anna Marousopoulou Antigoni Akrivou Emilia Markellou 《Environmental monitoring and assessment》2018,190(6):361
The persistence of glyphosate and its primary metabolite AMPA (aminomethylphosphonic acid) was monitored in two areas in Southern Greece (Peza, Crete and Chora Trifilias, Peloponnese) with a known history of glyphosate use, and the levels of residues were linked to spray operators’ activities in the respective areas. A total of 170 samples were collected and analysed from both areas during a 3-year monitoring study. A new method (Impact Assessment Procedure - IAP) designed to assess potential impacts to the environment caused by growers’ activities, was utilised in the explanation of the results. The level of residues was compared to the predicted environmental concentrations in soil. The ratio of the measured concentrations to the predicted environmental concentrations (MCs/PECs) was >?1 in Chora the first 2 years of sampling and <?1 in the third year, whilst the MCs/PECs ratio was <?1 in Peza, throughout the whole monitoring period. The compliance to the instructions for best handling practices, which operators received during the monitoring period, was reflected in the amount of residues and the MCs/PECs ratio in the second and especially the third sampling year. Differences in the level of residues between areas as well as sampling sites of the same area were identified. AMPA persisted longer than the parent compound glyphosate in both areas. 相似文献