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Environmental gradients across wetland vegetation groups in the arid slopes of Western Alborz Mountains, N. Iran

100%
Kamrani A., Naqinezhad A., Jalili A., Attar F.
Acta Societatis Botanicorum Poloniae
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2010
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tom 79
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nr 4
Mountain wetlands are unique ecosystems in the arid southern slopes of Alborz range, the second largest range in Iran. The spatial distribution characteristics of wetland vegetation in the arid region of the Alborz and the main factors affecting their distributional patterns were studied. A classification of vegetation and ecological characteristics were carried out using data extracted from 430 relevés in 90 wetland sites. The data were analyzed using Two Way Indicator Species Analysis (TWINSPAN) and detrended correspondence analysis (DCA). The wetland vegetation of Alborz Mountain was classified into four large groups. The first vegetation group was calcareous rich vegetation, mainly distributed in the river banks and characterized by helophytes such as Bolboschoenus affinis as indicator species. The second group was saline transitional vegetation, distributed in the ecotone areas and dominated by Phragmites australis. The third vegetation group is wet meadow vegetation which mainly consists of geophytes, endemic and Irano-Turanian species, distributed in the higher altitudes. This vegetation is mainly characterized by indicator species such as Carex orbicularis, high level concentration of Fe2+ and percentage of organic matter in the soil. The fourth vegetation group is aquatic vegetation, distributed in the lakeshores. The aquatic group species are mainly hydrophytic such as Batrachium trichophyllum. The TWINSPAN vegetation groups could be also recognized in the DCA graphs and ecologically differentiated by ANOVA of studied variables. Four vegetation groups can be differentiated on two first axes of indirect ordination. There is a gradient of pH, EC and organic matter associated with altitude on the DCA diagram. Correlation analysis between the axes of DCA and environmental factors shows that altitude, soil texture and other dependant environmental variables (e.g. pH) are the main environmental factors affecting the distribution of wetland vegetation groups.
2

Microbial properties and dehydrogenase activity in semiarid area, Kerman Province, Iran

100%
Teimouri M., Mohammadi P., Jalili A.
Polish Journal of Environmental Studies
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2019
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tom 28
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nr 2
Soil microbial and biochemical properties are important indicators in estimating soil degradation. This study aimed to determine the impact of site, season, and grazing on microbial population size, microbial biomass carbon, and dehydrogenase activity in two semiarid areas in Kerman Province, Iran. Soil samples were taken from four sites that were either cold or warm and either grazed or notgrazed over two seasons. Microbial count, microbial biomass carbon, and dehydrogenase activity were determined via plate count, fumigation-extraction, and colorometric methods, respectively. The statistical analysis showed a significant difference in fungal and bacterial plate count, microbial biomass, and dehydrogenase activity among the studied areas. Fungal and bacterial counts, microbial biomass carbon, and dehydrogenase activity were greater at cold sites compared to warm sites, possibly due to increased plant cover, soil organic carbon, and moisture. In addition, there was temporal variation in microbial properties and dehydrogenase activity with the increased activity of the spring samples. Grazing did not change the soil chemical properties but did alter its microbiological properties and dehydrogenase activity, indicating their greater sensitivity in estimating soil quality. Based on the measured microbial properties, the cold sites have an advantage in sustaining soil quality, and the warm sites are more likely to require protective management programs.
3

Total mercury in Aquaculture fish

64%
Hardisson A., Rubio C., Gutierrez A., Jalili A., Hernandez-Sanchez C., Lozano G., Revert C., Hernandez-Armas J.
Polish Journal of Environmental Studies
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2012
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tom 21
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nr 5
Three fish species from aquacultiire cages located along the coast of Tenerife island (Canary Islands, Spain) were analyzed: gilthead bream (Spams auratd), sea bass (Dicentrarchus labrax), and rainbow trout (Oncorhynchus mykiss). Cold vapor atomic absorption spectrometry was used to determine total mercury in 120 fish muscle samples. 0.037±0.04 mg/kg, 0.082±0.15 mg/kg, and 0.023±0.025 mg/kg wet weight of Hg were found for sea bass, gilthead bream, and rainbow trout, respectively. Due to these low Hg levels, the consumption of these species of aquaculture fish contributes very little to total Hg dietary intake.
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