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https://doi.org/10.21256/zhaw-19840| Publication type: | Bachelor thesis |
| Title: | Stream biofilm response to an increasing number of non-flow periods |
| Authors: | Etter, Ariane Fischer, Selina |
| Advisors / Reviewers: | Döring, Michael Acuña, Vicenç |
| DOI: | 10.21256/zhaw-19840 |
| Extent: | 75 |
| Issue Date: | 2020 |
| Publisher / Ed. Institution: | ZHAW Zürcher Hochschule für Angewandte Wissenschaften |
| Publisher / Ed. Institution: | Winterthur |
| Language: | English |
| Subjects: | Intermittent waterways; Intermittency; Non-flow period; Artificial streams; Stream biofilm; Frequency; Duration; Impact; Recovery; Autotrophic and heterotrophic activities; Function; Biomass |
| Subject (DDC): | 570: Biology |
| Abstract: | Anthropogenic impacts and climate change are considerably altering freshwater systems. Most significant consequences of this are changes to flow regimes as well as the transformation of permanent into temporary waterways. This is problematic, as despite their role in supporting biodiversity and ecosystem processes, temporary waterways are undervalued and poorly understood. In fact, although the effects of non-flow periods are known, there is a lack of knowledge regarding how changes in frequency and duration of non-flow periods influence temporary waterways. Therefore, the goal of further research is to extend the current knowledge surrounding the effects of temporal components on the aquatic ecosystem. This bachelor thesis aims to identify how the frequency of non-flow periods affects autotrophic and heterotrophic stream biofilm. With this objective, an experiment at the Experimental Stream Facility of Catalan Institute for Water Research (ICRA) was performed. The treatments consisted of one drought duration (28 days) and three frequencies (1 period of 28, 2 periods of 14, 4 periods of 7 non-flow days). The development of the autotrophic and heterotrophic stream biofilm was measured during flow periods by means of yield of photochemistry, aerobic respiration, ecosystem metabolism and ash free dry mass. The hypotheses were that with increasing frequency, the effects on stream biofilm are less because the number of subsequent non-flow days is smaller and thus the biofilm is less stressed, and that autotrophs in the epipsammic biofilm recover more slowly than in the epilithic biofilm, because the amount of water retained in sand is higher. Both hypotheses were partially confirmed, as an increasing frequency only lessened the effect on epipsammic biofilm and only autotrophic function recovered more slowly in sand than on cobbles. In addition, the majority of the variables experienced the most severe impact and thus the quickest recovery in the same treatment. Nevertheless, at the end of the experiment none of the differences persisted. Therefore, the frequency of non-flow periods only had an effect on a short-term but not on a long-term scale and consequently, both hypotheses were discarded. |
| URI: | https://digitalcollection.zhaw.ch/handle/11475/19840 |
| License (according to publishing contract): | Licence according to publishing contract |
| Departement: | Life Sciences and Facility Management |
| Appears in collections: | Bachelorarbeiten Umweltingenieurwesen |
Files in This Item:
| File | Description | Size | Format | |
|---|---|---|---|---|
| 2019_Etter_Ariane_und_Selina_Fischer_BA_UI.pdf | 7.31 MB | Adobe PDF |  View/Open |
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Etter, A., & Fischer, S. (2020). Stream biofilm response to an increasing number of non-flow periods [Bachelor’s thesis, ZHAW Zürcher Hochschule für Angewandte Wissenschaften]. https://doi.org/10.21256/zhaw-19840
Etter, A. and Fischer, S. (2020) Stream biofilm response to an increasing number of non-flow periods. Bachelor’s thesis. ZHAW Zürcher Hochschule für Angewandte Wissenschaften. Available at: https://doi.org/10.21256/zhaw-19840.
A. Etter and S. Fischer, “Stream biofilm response to an increasing number of non-flow periods,” Bachelor’s thesis, ZHAW Zürcher Hochschule für Angewandte Wissenschaften, Winterthur, 2020. doi: 10.21256/zhaw-19840.
ETTER, Ariane und Selina FISCHER, 2020. Stream biofilm response to an increasing number of non-flow periods. Bachelor’s thesis. Winterthur: ZHAW Zürcher Hochschule für Angewandte Wissenschaften
Etter, Ariane, and Selina Fischer. 2020. “Stream Biofilm Response to an Increasing Number of Non-Flow Periods.” Bachelor’s thesis, Winterthur: ZHAW Zürcher Hochschule für Angewandte Wissenschaften. https://doi.org/10.21256/zhaw-19840.
Etter, Ariane, and Selina Fischer. Stream Biofilm Response to an Increasing Number of Non-Flow Periods. ZHAW Zürcher Hochschule für Angewandte Wissenschaften, 2020, https://doi.org/10.21256/zhaw-19840.
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