Using Earthworms Eisenia fetida (Sav.) for Utilization of Expansive Littoral Plants Biomass

This paper presents the results of the process of vermicomposting waste biomass of littoral plants Typha latifolia, Iris pseudacorus, Ceratophyllum demersum in vermireactors, with the use of earthworms Eisenia fetida. It was observed that E. fetida may be used for rapid utilization of pure I. pseudacorus and C. demersum waste, but using the technology presented in this paper and the assumed observation time, it was not possible to recycle T. latifolia waste. Vermicomposts obtained were characterized by higher N, P, K, Ca, and Mg content compared to the initial plant biomass. The content of Cu, Mn, Zn, Cd, and Pb in vermicomposts did not exclude their application as a fertilizer. During vermicomposting of all littoral plants, the earthworm population was maintained up to day 70 of the experiment, with a slight decrease in their number (on average by 6%, p > 0.05), and since day 35, a significant loss in earthworm biomass was observed. The greatest loss of mean sum of biomass (49%, p < 0.05) was noted in a group of earthworms utilizing T. latifolia. The earthworms reproduced, with the greatest mean number (and the sum of biomass) of cocoons observed in a group of earthworms processing C. demersum. These values were greater by 32% and 38% respectively (p < 0.05), for the aforementioned characteristics of cocoons produced in the remaining experimental groups.