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Bobori DC Salvarina I 《Journal of environmental biology / Academy of Environmental Biology, India》2010,31(6):995-1000
The seasonal variation of fish species composition and abundance in gillnet catches (14-90 mm knot-to-knot) from the Greek part of the transboundary Lake Doirani was studied during the period 2006-2007. A total of 8,419 specimens weighing 182.3 kg and belonging to 9 species were caught. Catch composition differed with season. Thus, Rhodeus meridionalis dominated in terms of NPUE the spring, Perca fluviatilis the summer and Albumus macedonicus the autumn and winter catches. Cyprinids were generally the most abundant, with the cyprinids:percids biomass ratio ranging from 1.7 in summer to 14.8 in winter, supporting the eutrophic character of the lake. Richness and Shannon-Wiener diversity and evenness indices differed seasonally (ANOVA; p < 0.05). The abundance-biomass comparative (ABC) curves showed that fish communities were dominated by one or a few opportunistic species (e.g. Rhodeus meridionalis, Albumus macedonicus), which while dominated in number did not dominate in biomass, being small bodied. 相似文献
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Cheimonopoulou MT Bobori DC Theocharopoulos I Lazaridou M 《Environmental management》2011,47(2):279-290
Biological elements, such as benthic macroinvertebrates and fish, have been used in assessing the ecological quality of rivers
according to the requirements of the Water Framework Directive. However, the concurrent use of multiple organism groups provides
a broader perspective for such evaluations, since each biological element may respond differently to certain environmental
variables. In the present study, we assessed the ecological quality of a Greek river (RM4 type), during autumn 2003 and spring
2004 at 10 sites, with benthic macroinvertebrates and fish. Hydromorphological and physicochemical parameters, habitat structure,
and riparian vegetation were also considered. Pollution sensitive macroinvertebrate taxa were more abundant at headwaters,
which had good/excellent water quality according to the Hellenic Evaluation System (HES). The main river reaches possessed
moderate water quality, while downstream sites were mainly characterised as having bad or poor water quality, dominated by
pollution-tolerant macroinvertebrate taxa. Macroinvertebrates related strongly to local stressors as chemical degradation
(ordination analysis CCA) and riparian quality impairment (bivariate analysis) while fish did not. Fish were absent from the
severely impacted lower river reaches. Furthermore, external pathological signs were observed in fish caught at certain sites.
A combined use of both macroinvertebrates and fish in biomonitoring programs is proposed for providing a safer assessment
of local and regional habitat impairment. 相似文献
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