Halophilic diatom taxa are sensitive indicators of even short term changes in lowland lotic systems
نویسنده
چکیده
The occurrence and spread of halophilic diatom taxa in freshwater lotic ecosystems are infl uenced both by natural processes and anthropogenic pollution. Diatom assemblages were regularly monitored in lowland lotic systems in Hungary (Central Europe) during the unusually dry year of 2012. Highly pronounced changes in diatom composition were observed from spring to autumn. Halophilic taxa (especially Nitzschia sensu lato species) appeared in the dry autumn. In addition, the total relative abundances of halophilic species also increased up to autumn. Abundance of Nitzschia cf. lorenziana and Nitzschia tryblionella showed a positive correlation with chloride and phosphate concentration, while that of other taxa like Tryblionella apiculata or Tryblionella calida showed a positive correlation with the concentration of nitrate. Our fi ndings clearly demonstrated that these halophilic and mesohalophilic diatom taxa were sensitive indicators of even short-term changes in lowland lotic ecosystems, such as the increasing salt concentration from spring to autumn caused by the lack of rainfall and/or environmental loads.
منابع مشابه
Lotic Diatoms as Environmental Indicators for Modern and Paleo Studies
The ecological impacts of anthropogenic activities on aquatic environments have led to the development of new methods of environmental monitoring (Cohen et al 1993, Kelly and Whitton 1995). Benthic algae represent a ubiquitous group of photosynthetic organisms that play a pivotal role in stream food webs but may also be used for observing long-term trends in community changes that can occur bec...
متن کاملDiatom-based interpretation of sediment banding in an urbanized lake
Sediment stratigraphy and diatom succession were studied in an 80.5-cm core taken from the deepest part of Third Sister Lake, a small kettle hole in a recently urbanized landscape of southeastern Michigan. Alternating light clay and dark organic bands documented sporadic inputs of clay from outside the basin during rain events, rather than annual laminations. Urban construction activity also di...
متن کاملDiatoms as an indicator for tile drainage flow in a German lowland catchment
Background The separation of runoff components within a model simulation is of great importance for a successful implementation of management measures. Diatoms could be a promising indicator for tile drainage flow due to their diverse preferences to different aquatic habitats. In this study, we collected diatom samples of 9 sites (4 tile drainage, TD, and 5 river sites, Ri) in a German lowland ...
متن کاملDiatoms from lentic and lotic systems in Antioquia, Chocó and Santander Departments in Colombia.
In the tropical and subtropical regions, there is a large number of species which has not been yet described. The high possibility of extinction makes their inventory a priority. In this paper, 23 diatoms taxa from Andean lotic systems and lentic waterbodies localized in the Departments of Antioquia, Santander and Chocó, Colombia, are analyzed with light and scanning electron microscopy. Each t...
متن کاملUsing Benthic Diatoms as a Bioindicator to Assess Rural-urban River Conditions in Tropical Area: A Case Study in the Sai Gon River, Vietnam
The changes in diatom assemblages along an urban-to-rural gradient were characterized to assess the ecological status of the Sai Gon River, Vietnam. Diatoms and physico-chemical variables were measured at 10 stations during dry and rainy season. One-way ANOVA showed that diatom metrics and physicochemical variables were significantly different (p < 0.05) between the upper course sites and both ...
متن کامل