Successful preparation of compost from invasive Water hyacinth (Eichhornia crassipes) in Pokhara valley of Nepal.

Water hyacinth is an invasive species in lakes of Pokhara valley of Nepal. There is usual practice of removal of this species from the lake and its deposition in the shore of the lake. Wetland Friends of Nepal (WFN) carried out an experiment seeking alternative on whether this species can be recycled to useful resource. Accordingly, the project facilitated the establishment of a plant at Rupa lake area to carryout experiment on converting Water hyacinth into productive compost and fish feeding item. The experiment was locally administered by Bioresources Conservation Movement - a NPO at Rupa lake area. After the 3 months long experiment, compost was successfully prepared from this species, mixing some other materials as well. The chemical analysis of the compost was made to find the nutrient content, and it was found that the compost has acceptable amount of nutrients for plant growth.

The results of laboratory tests of compost from Water hyacinth are as follows:

The PH value of the compost was found 8.4.
The N, P, K content in common compost type is generally 1.0 %, 0.5 % and 1.0 % respectively. Likewise the N, P, K values in the farmyard manure falls under 0.5-1.0 %, 0.5 % & 0.5-1.0 % ranges respectively (pers. Comm. regional soil test laboratory of Pokhara Nepal). Laboratory test results show that the compost obtained from Water hyacinth has acceptable composition of N, P, K and pH; and can be used in agricultural land for crop production.

 
Further experiment on composting from Water hyacinth under more controlled conditions and replications is recommended. Laboratory tests of the compost for toxic elements are also highly recommended. Periodic laboratory tests of raw compost in certain time intervals of the experiment are highly recommended to determine the appropriate stage of composting. Identification of Carbon to Hydrogen ratio in the compost is crucial for agricultural application. It is also crucial to carryout experiment on the effects of raw compost from water hyacinth on agricultural crop production to find the best stage of composting.

For further information, please write to Wetland Friends of Nepal at info(at)wetlandsnepal.org. This experiment was funded by Toyota Environmental Activities Grant Program of Toyota Motor Corporation.