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61.
Concentration of heavy metals in aquatic animals mainly occurs due to industrial contamination. In this study, the concentrations of four heavy metals (cadmium, lead, mercury, and arsenic) in organs of two cyprinid fish and in water collected from three sections of the Kor River, Iran were determined using the inductively coupled plasma method. Pathological and hormonal changes due to metal contamination were also measured. The concentrations of heavy metals in tissue of fish from the middle sampling zone were significantly higher (p?<?0.05) than those from the other two sampling zones, whereas no significant differences (p?>?0.05) were detected between the two sexes and species. High levels of metals were found in the ovaries and testes; estradiol in females and progesterone and testosterone in males from the middle study site were significantly (p?<?0.05) lower than values from the other two sites. Pathological changes in blood cells, liver, and kidneys of fishes were significantly higher in highly polluted areas (middle sampling zone). These results show that industrial activities have polluted the river and that the maximum concentrations of Cd, Pb, and Hg were higher than the permissible levels for human consumption.  相似文献   
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Environmental Science and Pollution Research - Every year, almost eight million people die from tobacco-related diseases, among which around 1.2 million die from secondhand smoke (SHS) exposure....  相似文献   
63.
While fuzzy specialists commonly use homogeneous experts' knowledge to construct fuzzy models, it is much more difficult to deal with knowledge elicited from a heterogeneous group of experts. This issue is exemplified in the area of sustainable rangeland management (SRM). One way to deal with the diversity of opinions is to develop a fuzzy system for all experts and to combine all these, the so-called primary systems, into one multi-fuzzy model. To derive each of the primary fuzzy systems, several semi-structured interviews were held in three different areas of the Fars province in Southwest Iran using the knowledge of a group of administrative experts. To obtain the final output of the multi-fuzzy model, we applied different 'voting' methods. The first method simply uses the arithmetic average of the primary outputs as the final output of the multi-fuzzy model. This final output represents an estimation of the right rate of stocking (RRS). We also propose other (un)supervised voting methods. Most importantly, by harmonising the primary outputs such that outliers get less emphasis, we introduce an unsupervised voting method for calculating a weighted estimate of the RRS. This harmonising method is expected to provide a new useful tool for policymakers dealing with heterogenity in experts' opinions: it is especially useful where limited field data are available and one is forced to rely on experts' knowledge only. By constructing the three fuzzy models based on the elicitation of heterogeneous experts' knowledge, our study shows the multidimensional vaguenesses that exist in SRM. Finally, by comparing the final RRS with its common values, this study strongly points to the existence of overgrazing in pastures in the three regions of the Fars province in Southwest Iran.  相似文献   
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Environmental Science and Pollution Research - Daily transportation of wastes due to its environmental, financial, and social aspects has been considered a challenging issue in developing...  相似文献   
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Environmental Monitoring and Assessment - No studies have been carried out on the benthic harmful algal blooms (BHABs) along the Strait of Gibraltar in the Mediterranean, and little is known about...  相似文献   
68.
Environmental Science and Pollution Research - Trihalomethanes (THMs) are one of the most common classes of disinfection by-products. In this study, the temporospatial trends and health risks due...  相似文献   
69.
The photodegradation of some pesticides in water has been investigated. The kinetics of the photochemical processes is discussed and the photolytic half‐life is calculated. The objective of this paper is to present some of the recent results on the kinetics and on the products of sunlight‐induced reactions of Parathion, Gardona, Diazinon, Atrazine and Phenmediphame at low concentrations in distilled water and fresh water. The quantum yield, measured at 263 nm for Phenmediphame in aerated water at 5 × 10‐4 M and 30°C, was 1.4 × 10‐2, and for Parathion, measured at 300 nm in aqueous solution at 3.42 M at pH 6.4 and 25 °C, was 1.5 × 10‐3. The measured absorption spectra and the variable light intensity were used to estimate the environental phototransformation process and the persistence of these compounds in water.  相似文献   
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Based on the literature and on work conducted in Israel, the management of spider populations through habitat manipulation was found to be very helpful in controlling pest insects in various crops. Spiders were found to be reduced or eliminated by non-selective insecticides, although some resistance has been noted  相似文献   
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