244
The aim of reducing the fish is to increase the zooplankton population that
feeds on phytoplankton to create clearer water. Elimination of benthivorous fish
species also enhances quality of lake water in shallow lakes by decreasing the
resuspension of sediment as well as nutrient recycling caused due to activity of
fishes (Jeppesen et al. 2012; Fulton et al. 2015) and reducing the quantity of loose
sediment (Scheffer et  al. 2003). Many biomanipulation examples have been
recorded in the past (Jeppesen et al. 2012; Hansson et al. 1998; Søndergaard et al.
2008; Peretyatko et al. 2012; Meijer et al. 1999), and the effects have sometimes
been weak (Gulati and van Donk 2002; Søndergaard et al. 2007). In some biomanipulation projects, a tendency to return to the earlier turbid conditions after
5–10 years has been noticed (Søndergaard et al. 2008). Adequate decrease of the
To Pump
To Pump
GROUND WATER TABLE
CONTAMINATION SOURCE
GROUND WATER TABLE
CONTAMINATION SOURCE
Fig. 12.4 Lowering a water table to eliminate contact with contaminated soil
12 Restoration