Change search
ReferencesLink to record
Permanent link

Direct link
How does nutrients and light affect algal growth in Swedish headwater streams?: A study using nutrient diffusing substrate and natural gradients of light
Umeå University, Faculty of Science and Technology, Department of Ecology and Environmental Sciences.
2014 (English)Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesisAlternative title
Hur påverkar näring och ljus algtillväxt i svenska bäckar? : En studie med diffunderande näringssubstrat och naturliga ljusgradienter (Swedish)
Abstract [en]

Gaining knowledge about what factors determine benthic algal biomass and productivity is vital for understanding food webs in aquatic systems, especially in woodland streams with naturally low rates of primary productivity. The aim of this study was to investigate what factors determine algal growth in Swedish headwater streams. Nutrients, in terms of nitrogen (N) and phosphorus (P), and light are factors known to affect algal growth. By using nutrient diffusing substrate (NDS) and different gradients of light, it was possible to test the importance of these factors. To determine the effect of the experiment, the study was carried out in a forested reference stream, which is largely shaded with extreme low nutrient levels, and in a stream running through a clear-cutting plantation with high nutrient levels and incident light. In the forested reference stream it became clear that algal growth increased by experimentally adding N (P<0.005), although light did not affect the productivity. In the stream running through the clear-cut, algal productivity increased significantly with higher levels of light (P<0.005), regardless of nutrient addition. The results from this study suggest that light only becomes the depending factor when sufficient amounts of nutrients are available. However, it is still unclear at what nutrient levels this shift occur, and therefore future research is recommended.

Place, publisher, year, edition, pages
Keyword [en]
: boreal streams, algal productivity, N limitation, nutrient diffusing substrate, incident light
National Category
URN: urn:nbn:se:umu:diva-101585OAI: diva2:800734
Educational program
Bachelor of Science in Biology and Earthscience
Available from: 2015-04-08 Created: 2015-04-07 Last updated: 2015-04-08Bibliographically approved

Open Access in DiVA

fulltext(1046 kB)270 downloads
File information
File name FULLTEXT01.pdfFile size 1046 kBChecksum SHA-512
Type fulltextMimetype application/pdf

By organisation
Department of Ecology and Environmental Sciences

Search outside of DiVA

GoogleGoogle Scholar
Total: 270 downloads
The number of downloads is the sum of all downloads of full texts. It may include eg previous versions that are now no longer available

Total: 239 hits
ReferencesLink to record
Permanent link

Direct link