Effects of the Digestate Produced by the Bio-Digester EB.06019.LHT-MWINDA on the pH of Kimwenza-Mission Soil and the Growth of Amaranthus cruentus
Balthazar K. Mukuna
Laboratoire de Bioénergie, Groupe de Génies Congolais, Faculté de Science et Technologie, Université Loyola du Congo, Kinshasa, Democratic Republic of the Congo.
Justine M. Monga
Laboratoire de Bioénergie, Groupe de Génies Congolais, Faculté de Science et Technologie, Université Loyola du Congo, Kinshasa, Democratic Republic of the Congo.
Gaston L. Wembi
Laboratoire de Bioénergie, Groupe de Génies Congolais, Faculté de Science et Technologie, Université Loyola du Congo, Kinshasa, Democratic Republic of the Congo.
Alphonsine Ipassou
Laboratoire de Bioénergie, Groupe de Génies Congolais, Faculté de Science et Technologie, Université Loyola du Congo, Kinshasa, Democratic Republic of the Congo.
Pierre L. Lokadi *
Laboratoire de Bioénergie, Groupe de Génies Congolais, Faculté de Science et Technologie, Université Loyola du Congo, Kinshasa, Democratic Republic of the Congo and Sophia University, Faculty of Sciences and Technology, Tokyo, Japan.
*Author to whom correspondence should be addressed.
Abstract
The evaluation of the effects of the digestate produced by the reactor EB.06019.LHT-MWINDA on the pH of Kimwenza soil and the growth of Amaranthus cruentus was conducted during the dry season (June-July 2019). Two treatments were used for the experiment: NPK (T1) and digestate (T2). The untreated soil was taken as a negative control(T0). The results obtained show that the digestate has a more neutralizing effect on the acidity of the Kimwenza-mission soil than the mineral fertilizer: the pH increased from 4.40 ± 0.33 to 9.28 ± 0.45 for T2 versus 5.19 ± 0.59 to 7.71 ± 0.29 for T1. The plants treated with T2 gave leaves with relatively more weight (1.8 ± 0.5g) than those obtained with T1 (1.06 ± 0.87g). It was observed that plants treated with digestate were taller (10,4 ±1,1m) than those with NPK (9,45 ±1,13m). The average number of leaves obtained from plants was 7.06 ; 6.36 and 5.97 respectively for T2, T1 and T0. These results are an indication that the digestate produced by the reactor EB.06019.LHT-MWINDA could be used for the amendment of the acidic soil of Kimwenza-Mission and therefore contribute to reducing significantly the use of synthetic agro-chemicals, hence decreasing residual environmental and human health hazards.
Keywords: Digestate, fertilizer, soil, Amaranthus cruentus, kimwenza.