RESUMO
The experiment was under taken during the year 2007-08 to study the effect of long term fertilization and manuring on labile carbon and N mineralization. The dynamics of C and N was studied in the ongoing long term fertilizer experiment initiated since kharif 1988 at Akola, Maharashtra. The experiment comprised of twelve treatments including NPK levels with and without FYM, sulphur and zinc replicated four times in randomised block design. The manure and fertilizers were given to sorghum crop every year and only fertilizers were applied to wheat crop. The soil samples from all the treatments were collected from 0-20 cm depth. The highest and significant increase in the, labile carbon, and NO3 - N and NH3 - N were recorded in the treatment of 10 t FYM ha-1 + 100% NPK (100:50:40 kg NPK for sorghum and 120:60:60 kg NPK for wheat) by 40.1, 18.5 and 29.0 per cent respectively over 100% recommended NPK.