Short-Term Biochemical Impacts in <i>Cyphoderus javanus</i> Borner (Collembola) as Potential Biomarkers of Fly Ash and Heavy Metal Pollution in Tropical Lateritic Soil

Abstract

The detritivorous soil microarthropods are ideal models for environmental health assessment, but only scant information is available on their biomarker potentials against xenobiotics in the tropical edaphic conditions. This microcosm study has estimated short-term biochemical changes with respect to tissue nutrient levels and digestive enzyme activities in a near cosmopolitan Collembola Cyphoderus javanus Borner exposed to coal fly ash amended lateritic cropland soil (5% and 20% w/w i.e. 50 or 200 t ·ha -1 ), and cadmium sulphate (200 mg/kg soil)/lead acetate (200 mg/kg soil) treated sterile river sand. The levels of total tissue carbohydrates, proteins, free amino acids, and lipids decrease within 7 days in the specimens of fly ash (P < 0.001) and heavy metals treated sets. The α -amylase, cellulase and protease activities are also down regulated by fly ash and heavy metals (P < 0.05). It is also observed the enzyme: protein ratios increase in fly ash treated sets and decrease in lead and cadmium treated specimens. Specimens in treated sets accumulate high levels of lead and cadmium within 15 days, which decrease subsequently probably due to elimination through frequent moulting. These short-term biochemical effects in Collembola have applied importance in C. javanus, as biomarkers for quick ecotoxicological assessments in the tropical agricultural soils.