Characterization of Vermicomposts Prepared from Agricultural Solid Wastes in North Eastern Hill Region of Nagaland, India

Abstract

To evaluate the vermicompost derived from agricultural solid wastes used as bedding material and to identify a superior vermicompost over the conventional vermicompost made from cow dung and paddy straw, an experiment was conducted with four sources of different plant biomass and animal excreta. These vermicomposts were tested for moisture content, pH, electrical conductivity, ash content, C:N ratio, different fractions of carbon (C), nitrogen (N), phosphorus (P), potassium (K), and sulphur (S) by standard procedures. The moisture content decreased at maturity ranged from 9.59 to 29.91 %. Total organic C decreased by 2.90–24.90 %; whereas, total N was increased by 0.56 % (range 0.04–1.33 %) during 40–80 days of the decomposition. The results clearly elucidated the decrease in C:N ratio in the matured product. When poultry dropping was used as one of the bedding material, total P content was increased. Hierarchical cluster analysis showed that vermicomposts prepared from cow dung and pig dung as well as rabbit dung and poultry droppings are relatively homogeneous. It was concluded that the physical characteristics, chemical characteristics and nutrient content of the matured vermicomposts are mainly influenced by the animal excreta used as bedding material and concentration of nutrients is increased at maturity. Since the vermicomposts have high nutritive value with narrow C:N ratio, these are highly favourable for the application in the field.