Vermicomposting process for treating animal slurry in Latin American rural areas

Abstract

The management of animal slurry is a big issue in low-income rural areas worldwide. Bolivia suffers this issue related to collection, treatment and final disposal since the main solution applied is the open dumping. The aim of this study is to introduce a feasible treatment of animal slurry in the rural area of Carmen Pampa, where about 670 kg of dung are produced per day and disposed of in open areas. The objective is the improvement of the environmental sustainability and human health, providing an alternative solution for encouraging the circular economy. The study is focused on the vermicomposting process, a sustainable solution for low-income regions. The analysis was conducted in function of the earthworm breeds used locally ( Eisenia fetida and Lumbricus terrestris) and the application of activated bacteria (AB) for improving the process. The mass loss, the treatment time, and the growing rate of the earthworms were analyzed. The results suggest that the different breed of the worms allows gaining up to 19 days, while the use of the AB allows saving about 30 days. Moreover, the vermicomposting process reduced the mass of the slurry of about 65% for the swine’s dung and the bovine’s dung, and 90% of the hens’ dung. Finally, experimental evidence shows that the growing rate of the E. fetida is higher than the L. terrestris (F[1,8] = 78, p < 0.05), with an average of about 193%. The data obtained could be of interest for other stakeholders who live in similar environmental, climatic, and economic conditions for improving sustainability.

Can tourism support resource circularity in small islands? On-field analysis and intervention proposals in Madagascar

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Vermicomposting: A Valorization Alternative for Corn Cob Waste

“…As per Yadav and Garg, acceptable pH range for the vermicomposting process is between 5.5 and 8 [58,59]; while Ali et al have pointed out that a neutral pH is adequate for the proper development of worms, although they may survive in a range of 4.5 to [10].…”

Effects of vermicompost on plant and soil characteristics - a literature overview

“…This process is called vermicomposting. A typical mass balance for the processing of dairy manure by earthworms is shown in Figure 1 (Nova Pinedo et al, 2019).…”