Menu

Javascript is not activated in your browser. This website needs javascript activated to work properly.
You are here

Effect of riparian structure, temperature and channel morphometry on detritus processing in channelized and natural woodland streams in southern Sweden

Author:
  • Lena Vought
  • Anders Kullberg
  • Robert C. Petersen
Publishing year: 1998
Language: English
Pages: 273-285
Publication/Series: Aquatic Conservation
Volume: 8
Issue: 2
Document type: Journal article
Publisher: John Wiley & Sons

Abstract english

1. Ten south Swedish streams were selected to represent two distinct types - natural woodland streams and channelized streams. Measurements were made on leaching, decomposition and microbial respiration of the dominant riparian vegetation (European Black Alder), structure of the benthic macroinvertebrate community, macroinvertebrates inhabiting leaf material, channel morphometry, macrophyte composition, water chemistry and total accumulated degree days.

2. Leaf decomposition rates were not significantly different when channelized streams were compared with natural woodland streams. In channelized streams the average decomposition rate was -0.0556±0.0337 (±S.D.) day-1 compared with -0.0457±0.0115 day-1 in natural woodland streams.

3. There was significantly higher variation in leaf decomposition among the five channelized streams compared with the five natural streams (F-test, p<0.05). This was mainly due to extremely high decomposition rates in channelized streams colonized by emergent macrophytes.

4. Alder decomposition rates were low in channelized streams without macrophytes (-0.0053 °day-1), intermediate in natural streams (-0.0087 °day-1), and high in channelized streams with macrophytes (-0.0136 °day-1).

5. The shredder functional group ranged from 13 to 70% of the benthic community in the natural streams. Channelized streams had a more variable shredder population ranging from 0.5 to 80%. The highest values were found in channelized streams that had become colonized by macrophytes.

6. There was a significant difference in total accumulated degree days between the channelized (256 °day) and natural woodland streams (209 °day). This is most likely an effect of drainage tiles contributing warmer groundwater to the channelized streams during fall.

7. It is concluded that, contrary to the prevailing conceptual model of stream systems, decomposition rates and macroinvertebrate functions are not necessarily reduced in streams without riparian vegetation. The loss of the riparian canopy can stimulate emergent macrophytes which will provide autochthonous detritus for benthic communities. This will change benthic community structure and the life cycle strategies present.

Keywords

  • Ecology
  • Environmental Sciences
  • channelized
  • stream
  • functional group
  • invertebrates
  • leaf pack
  • decomposition
  • riparian
  • detritus

Other

Published
  • ISSN: 1052-7613
Anders Kullberg
E-mail: anders [dot] kullberg [at] biol [dot] lu [dot] se

IT coordinator

Administration Office (Science)

+46 46 222 44 53

B121B

Sölvegatan 27, Lund

39

IT coordinator

Department of Biology

+46 46 222 44 53

E-B160

Sölvegatan 37, Lund

50