Conversion of water hyacinth (Eichhornia crassipes) into nutrient-rich fertilizer by pit methods.

Among the aquatic weeds, water hyacinth is considered to be the most obnoxious of all aquatic weeds and occupies eighth rank in the world. Water hyacinth caused lot of problems to human beings and animals in many ways. The present study is therefore aimed to develop an appropriate technology for recovery of resources from aquatic weeds by pit methods of composting. Compost was prepared from aquatic weed water hyacinth using three different pit methods namely Indore method, Bangalore method and phospho-compost method. Physical and chemical parameters of the compost were analyzed in the initial and final stage. The physical analyzes of composts showed that electrical conductivity, porosity, water holding capacity and moisture content were increased from initial to final stage in all pit methods especially in Bangalore method. The drastic reduction was noticed in lignin and cellulose level of composts especially in Bangalore compost. All the three compost have recorded higher macro and micro nutrients especially in Bangalore compost from initial to final stage. Among the three composts, Bangalore compost recorded the highest reduction in C: N ratio followed by phospho-compost and Indoor compost. Increased bacterial and fungal counts were observed in Bangalore compost than the Indore and phospho-compost. The generic compositions of bacterial and fungal strains of three composts were revealed that more or less same types of genera were present. In this context we conclude that all the three techniques of composting are best suitable to replenish the Eichhornia weed biomass. Water hyacinth based compost used as an organic fertilizer has appropriate macro and micro nutrients and microorganisms that will support the plant growth. _____________________________________________________________________________________________________________