Impact of oxygen released by the roots of aquatic macro-phytes on composition and distribution of benthic macroinvertebrates in a mesocosm experiment
Ságová-Marecková, Marketa; Kvet, Jan
published: Dec 9, 2002
ArtNo. ESP141015504003, Price: 29.00 €
Abundance of benthic macroinvertebrates was studied in relationship to the presence of roots of aquatic macrophytes, sediment type and oxygen concentrations in the root zone. In tanks, four species (in 1997) or six species (in 1998) of macrophytes and two sediment mixtures were used as treatments. Significantly more animals were found regularly in the root zone of macrophytes than in the plant-free sediment. Sediment mixture did not have much influence on the animal numbers but size of chironomids (body width) was greater in the sediment mixture with higher organic matter content. Oxygen concentration was always significantly higher in the root zone of macrophytes than in the plant-free sediment. Also, the oxygen concentration in the root zone was species specific and was similar in the two years of observation. Abundance of chironomids in the first year and oligochaetes in the second year showed significant positive regression with oxygen concentration.