Suspension feeders transform massive amounts of seston in large northern rivers

• DOI: 10.1034/j.1600-0706.2001.920105.x
• Publication Date: 2004-12-27T18:34:21Z
• Authors: Björn Malmqvist; Roger S. Wotton; Yixin Zhang
• Keywords: Seston; Dry weight; Sedimentation; Suspension

The concentration and transport of faecal pellets (FPs) produced by blackfly (Diptera: Simuliidae) larvae were estimated in a large, free‐flowing river the north Sweden during 1997–1999. FPs abundant from May through August FP loads peaked at 429 t dry mass d−1 site lower part 1997. Daily same site, averaged over each study period (16 Jun.–18 Sep. 1997, 6 Apr.–10 1998, 21 Apr.–5 Aug. 1999), was to be 93.7 (3.7 carbon), 47.5 (1.9 carbon and) 69.2 (2.7 respectively. On large scale, there downstream trend increasing and, periods with greater discharge, sedimentation reduced so that more material exported river. Samples six sites regulated (into which our focal flows) parallel unregulated tributary showed considerably concentrations river, presumably because much smaller populations as consequence habitat loss damming. A survey two other rivers northern confirmed these also carry amounts FPs. We conclude transformation small suspended food particles into larger huge filter‐feeding is major process rivers.