The effects of common carp bioturbation on fishpond bottom soil

摘要: Abstract Bioturbation activity generated by fish has the potential to improve bottom soil quality increasing oxygen supply a greater depth in aquaculture ponds bottoms. This study was designed assess common carp ( Cyprinus carpio L) conditions pond soils. Enclosures (3×2 m) constructed within tilapia production were stocked with zero, two or seven each. Treatments triplicated (four replicates used for control treatment). Carp not fed prepared diet during study. Fluorescent stained quartz particles added soils (as bioturbation tracer) enclosures. Bottom cores taken from enclosures sectioned 0–1, 1–2, 2–3 and 3–5 cm layers. Total dissolved sulfide (TDS), soluble Mn, easily oxidized matter (EOM), exchangeable NH 4 -N determined. Concentrations of all above measured constituents, 45 days after stocking, along profile that contained fish, lower than without fish. Bulk density surface containing significantly control. Tracer analysis results indicated more displaced down 3-cm as compared control, suggesting stirring effective approximately 3 cm. Pond perturbation increases transfer soil, decrease concentration toxic reduced compounds enable efficient food web recycling nutrient release.