Distribution of the macrophyte communities in the Danube reflects river serial discontinuity

Janauer, Georg A. (author), Germ, Mateja (author), Holcar, Matej (author), Zelnik, Igor (author), Gaberščik, Alenka (author)

The Danube is the second-longest river in Europe that is subjected to various man-made alterations, including those related to hydro-power plants. We surveyed and analyzed the presence and abundance of macrophytes in the main channel from 2582 river kilometers (rkm) to 171 rkm. We also assessed selected habitat parameters in the sampled river stretches. Sixty-eight different plant species were recorded along the entire course. Among neophytes, we found Elodea nuttallii, E. canadensis, Vallisneria spiralis and Azolla filiculoides. Based on similarity analysis, we distinguished 15 plant communities, most of which were defined as associations, which were classified into 5 alliances and represented three vegetation classes, namely vegetation of rooted hydrophytes Potamogetonetea, the vegetation of pleustophytes Lemnetea and vegetation of marshes Phragmitetea. The number and abundance of plant species, as well as plant communities recorded in single stretches, varied along the course. Canonical correspondence analysis (CCA) revealed that environmental parameters explained 21% of plant species composition. CCA runs with neophytes explained 41% of the variance, and current velocity, water transparency, species number and bank structure were significant variables. The present study revealed that the free-running sections of the river are poor in number and abundance of plant species, whereas impounded reaches mainly show an opposite result.

• Language: English
• Keywords: Danube, large river, macrophytes, neophytes, plant communities, distribution
• Work type: Article
• Typology: 1.01 - Original Scientific Article
• Organization: BF - Biotechnical Faculty
• Publication status: Published
• Publication version: Version of Record
• Year: 2021
• Number of pages: 24 str.
• Numbering: Vol. 13, iss. 7, art. 918
• PID: 20.500.12556/RUL-135011
• UDC: 574
• ISSN on article: 2073-4441
• DOI: 10.3390/w13070918
• COBISS.SI-ID: 58377987
• Publication date in RUL: 17.02.2022

Record is a part of a journal

• Title: Water
• Shortened title: Water
• Publisher: Molecular Diversity Preservation International - MDPI
• ISSN: 2073-4441
• COBISS.SI-ID: 36731653

Licences

• License: CC BY 4.0, Creative Commons Attribution 4.0 International
• Link: http://creativecommons.org/licenses/by/4.0/
• Description: This is the standard Creative Commons license that gives others maximum freedom to do what they want with the work as long as they credit the author.
• Licensing start date: 01.04.2021

Secondary language

• Language: Slovenian
• Keywords: Donava, velike reke, makrofiti, neofiti, rastlinske združbe, razširjenost