Assessment of Fertilised Pond Ecosystem Productivity Using Aerobic Cellulose Decomposing Bacteria as Carbon Signature

The growth response of aerobic cellulose decomposing bacteria (CDB) to qualitatively different fertilisers [cattle manure (CM), poultry droppings (PD), inorganic fertiliser (IF)] were examined in experimental tanks under alluvial and laterite soil conditions as well as in natural ponds with alluvial soil. A mixed application of fertiliser [organic - PD (14 kg); CM (44.5 kg) and inorganic - urea (557g); single super phosphate- 3.14 g] was applied in natural ponds. The maximum CDB population occurred in CM treatment (water: 52 280 x 10^3 mL-1; sediment: 38- 278 x 10^4 g-1 ) followed by mixed application (pond water: 122-212 x10^3 mL-1; sediment: 58-206 x 10^4 g-1), PD (water: 42-195 x 10^3 mL-1; sediment: 21-200 x 10^4 g-1 ), and IF (water: 3.3-72 x 10^3 mL-1 ; sediment: 2.5- 58 x 10^4 g-1). Higher values of C/N (61-116.3) and N/P (1.89-2.28) ratios in the CM treatment suggest that carbon was not limiting in the CM, and the CDB populations therefore can be a good indicator of carbon status in wetlands. Hence, CDB population in pond ecosystem can serve as carbon signature of the system productivity supporting necessary carbon amendments through manuring in the system for enhanced production.