دانلود رایگان مقاله ماکروفیتها مانند ویژگی فیزیکوشیمیایی بیواندیکاتور تالاب ها در شبه جزیره بالکان

Abstract

The simultaneous monitoring of vegetation, water and sediments was conducted in wetlands of the central Balkan Peninsula due to the lack of available knowledge on the univariate response of macrophytes along environmental gradients. The environmental preferences and bioindicator potential of macrophytes were assessed using Huisman-Olff-Fresco (HOF) models. Bolboschoenus maritimus and Scirpus lacustris subsp. tabernaemontani are valuable bioindicators of slightly saline (electroconductivity of 2000–4000 S cm−1 in the sediment) and alkaline habitats that are rich in SO4 2−. Their ecological niches are partially overlapped. Bolboschoenus maritimus prefers saltier and more alkaline habitats for optimal development. The salinity and alkalinity of habitats are decisive factors in the ecological diversification of the Boloboschoenus species. Bolboschoenus glaucus is adapted to non-saline (400–900 S cm−1) and slightly alkaline habitats, unlike Bolboschoenus maritimus. Relatively deep, slightly acid waters which are poor in SO4 2− (0.30 mg/l), and sediments with low values of electroconductivity and K2O (6.8 mg/100 g sediment) are preferred by Typha angustifolia, Sparganium erectum and Typha latifolia. The abundance of Phalaris arundinacea, Scirpus lacustris, Carex riparia and Eleocharis palustris increases when there is a decrease in the amount of nutrients (NH4 +, PO4 3− and SO4 2−) in the water. Phragmites australis has low indicative value and regional bioindicator potential. The data obtained in the study may serve as a basis for adjusting the existing indicator values of these species and extending indicator systems by defining the indicator values of species with respect to environmental variables which have not yet been considered.

4. Discussion

The environmental preferences established using the HOF models and data published in relevant literature sources could be used as a basis for assessing the bioindicator potential of the macrophytes studied here. However, a comparison between these results and those already published would be difficult for the following reasons: 1) literature sources rarely contain information about the ecological optimum values and ecological tolerances of particular species with respect to local or regional estimated environmental variables (Stechová ˇ et al., 2008; Ugurlu ˘ and Oldeland, 2012), 2) the values of measurement for environmental variables are expressed as their ranges or mean/median values (Onaindia et al., 2005), 3) the assessment of bioindicator potential is often given for the communities (Kłosowski and Jabłonska, ´ 2009; Lukács et al., 2009) and not for their indicator species. Although the ecological amplitudes of communities are not the same as the ecological amplitudes of their indicator species (Pełechaty, 1999), such data are significant. They provide information about the regional differences between habitats in terms of their physicochemical properties and possible stochastic occurrences of the species in suboptimal conditions (Stechová ˇ et al., 2008).