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991.
This study was designed to investigate the composition and the toxicity of leather tanning wastewater and conditioned sludge collected at the leather tanning wastewater treatment plant (CODISO) located in Solofra, Avellino (Southern Italy). Samples were analyzed for their conventional parameters (COD, TSS, chromium and ammonia) and for metal content. Effluent samples included raw wastewater, and samples collected following coagulation/flocculation process and biological treatment. A set of toxicity endpoints were tested using sea urchin and marine microalgal bioassays by evaluating acute embryotoxicity, developmental defects, changes in sperm fertilization success and transmissible damage from sperm to the offspring, and changes in algal growth rate. Dose-related toxicity to sea urchin embryogenesis and sperm fertilization success was exerted by effluent or sludge samples according to the following rank: conditioned sludge > coagulated effluent > or = raw influent > effluent from biological treatment. Offspring quality was not affected by sperm exposure to any wastewater or to sludge samples. Algal growth was inhibited by raw or coagulated effluent to a similar extent and, again, the effluent from the biological treatment resulted in a decreased toxicity. The results suggest that coagulated effluent and conditioned sludge result in higher toxicity than raw influent in sea urchin embryos and sperm, whereas the biological wastewater treatment of coagulated effluent, in both sea urchins and algae, cause a substantial improvement of wastewater quality. Hence a final biological wastewater treatment should be operated to minimize any environmental damage from tannery wastewater.  相似文献   
992.
Environmental Science and Pollution Research - The presence of toxic chlorinated compounds in drinking water, generated during the disinfection step in water treatment plants, is of great concern...  相似文献   
993.
994.
Environmental Science and Pollution Research - Occupational exposure to pesticides has been identified as a major trigger of the development of cancer. Pesticides can cause intoxication in the...  相似文献   
995.
A solid-phase microextraction (SPME) procedure has been developed to extract eight organophosphorus pesticides (OPs) in water and the method was compared with a conventional solid phase extraction (SPE) technique. The extracted OPs were analyzed by gas chromatography using thermionic specific detection. Both extraction methods presented linear calibration at least over the concentration range investigated (100 to 1000 ng x mL(-1) for SPE and 1 to 100 ng x mL(-1) for SPME). SPME method presented higher sensitivity than SPE. The quantitation limits were between 0.1 to 1.0 ng x mL(-1) for SPME depending upon the analyte, and 100 ng x mL(-1) for SPE. The precision, as measured by the standard deviations (RSD), were in the range 3.6% to 5.8% for SPME and 2.4% to 9.2% for SPE. Along with the feature of being a solvent - free sampling technique, SPME offers additional benefits due to its high sensitivity, simplicity, and small size sample required (typically: SPE - 500 mL, SPME - 5 mL).  相似文献   
996.
Observations from the purse seine fishery off northern Portugal are used to describe the early dynamics of sardine (Sardina pilchardus) stress reactions and identify likely stressors during the commercial fishing operation. Sardine blood and muscle were sampled from the onset of fishing (school identification and encircling) to the end of fish transfer onboard (90–120 min later). The evolution of haematocrit, haemoglobin, cortisol, glucose, ionic concentrations, ATP and its catabolites were modelled using linear mixed models as a function of time spent in the net, biological (sex, reproductive state and condition) and operational variables (catch, light level and phase of fishing operation). Significant linear trends with time were detected for most stress variables and mean concentrations after 2 h in the net were similar to literature values corresponding to acute stress reactions for teleosts. Biological variables were rarely significant and explained a small proportion of variation, while operational variables were never significant. For each stress variable, levels varied considerably between trips but the temporal evolution was common across trips. Random trip effects were uncorrelated among most biochemical variables, suggesting that distinct factors affected each stress variable during the sampled trips. However, the linear trend with time spent in the net observed for most stress variables indicates that the duration of the fishing operation is an important stressor in purse seine fishing due to the progressive water volume restriction, crowding and manipulation associated to the fishing method.  相似文献   
997.
In this work we studied the trophic ecology and feeding impact of the cladoceran Penilia avirostris and the cyclopoid copepod Oithona nana, the two dominant zooplankters in the summer communities of the coastal NW Mediterranean, on the naturally occurring microbial communities. In order to ascertain carbon surplus for growth and reproduction and the contribution to carbon and nitrogen recycling of these two species, we also determined their basal metabolism and excretion rates. The experiments conducted during summers 2002, 2003, and 2004 indicate that P. avirostris grazed mostly upon small flagellates, dinoflagellates, and diatoms, whereas O. nana had a narrower prey range, selecting motile organisms such as ciliates and occasionally dinoflagellates. The grazing impact of both species accounted, on average, for <10% of the standing stock of the microbial groups considered. In spite of the oligotrophic conditions, the feeding activity of P. avirostris is in general sufficient to compensate basal metabolism and allows a surplus for growth and reproduction. This was not the case for O. nana, its daily rations being often lower than the carbon basal demands. Regarding excretion rates, both species presented different N:P excretion ratios, the ones of O. nana falling within values typical for copepods, whereas the absence of detectable phosphorus excretion by P. avirostris implied an unbalance recycling with respect to typical Redfield ratio composition of marine seston.  相似文献   
998.
One of the most endangered species in tropical seas, Chelonia mydas (green turtles) prefer undisturbed sand beaches to lay their eggs. While Caretta caretta lays their eggs all over the Mediterranean beaches of Turkey, C. mydas nesting locations are limited with north-eastern site (Alata, Kazanli, Akyatan and Samandag) of the country and some beaches in Cyprus. Until 2003, no nesting place of both species between Akyatan and Samandag was recorded. From north to south, the beaches examined in 2003 summer are Arsuz, Konacik, Kale, Tr-H-3, Tr-H-2, and Tr-H-1 in addition to well-known and studied nesting beaches of sea turtle species in Hatay Province: Cevlik, Seyhhizir and Meydan. Since the Hatay Provincial Coast between Cevlik and Arsuz is hilly and no stabilized road is available, these small beaches were not known to have both C. mydas and C. caretta nests. Some physical and chemical sand properties, the number of nests belong to both species and selected nest specifications were investigated in this study. Kale Beach was found to be the most important nesting place in this less populated area. Based on results, Kale, Tr-H-3 and Tr-H-1 beaches were recorded to have high hatchling success.  相似文献   
999.
This study aimed to assess how poor planning for irrigation led to heavy salt loads, how those salt loads adversely affected the environment, and how to identify management practices to deal with these potential problems in the Great Menderes River Basin, Aydin Plain Irrigation Scheme of Turkey for the period between 2000 and 2006. In order to determine the effects on the environment; electrical conductivity, salinity load, total amount of water table salinity, inflow and outflow salinity were measured and calculated for the research area. There was no problem on account of water table fluctuations. The mean of area prevented the plant growth by high water table was 8.5%. The percentage of the area occurring water table salinity problem was 39.2. The total amount of salt transported to the Great Menderes River and accumulated in the soil of the research area was 211,609 and 246,565 tones respectively. Salt, 458,174 tones in total, had adverse effects on the environment.  相似文献   
1000.
Inorganic chemical composition of native trees of the Atlantic Forest   总被引:1,自引:0,他引:1  
The Atlantic Forest with its exuberant vegetation of high level of biodiversity is classified as one hotspot of the world. Chemical composition of leaves from native trees and underlying soils was evaluated by INAA. The predominant species Euterpe edulis, Bathysa meridionalis, Hyeronima alchorneoides, Marlierea tomentosa, Gomidesia flagellaris, and Gomidesia spectabilis belonging to the diverse plant families were studied. Euterpe edulis, the most abundant understory specie, presented the lowest element concentrations except for Zn. Some variation in chemical composition was noted, however, the chemical specificity of tree species can be more predominant than the soil variability for the obtained leaf concentrations. Factor values obtained through the Monte-Carlo assisted factor analysis were used for species discrimination. The results indicate that chemical investigation of native trees is a quite promising tool for biodiversity studies in the Atlantic Forest.  相似文献   
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