The study of soil biological and chemical properties on palm oil plant rhizosphere with and without palm oil mill effluent applications

Abstract

Palm oil mill effluent (POME) is a by-product of palm oil mills. POME application to the field must comply with the regulations issued by the Minister of Environment. The research objective was to determine the soil biological and chemical properties in the rhizosphere of palm oil plant on the land with and without POME application. The research used factorial randomized block design (RBD) with 2 treatments, the first factor was with and without POME application. The second factor was the sample distance from palm oil trees, namely 0 m, 100 cm, 200 cm, 300 cm and 400 cm. Data were analyzed with the analysis of variance at a 5% level and continued with the DMRT at significantly different treatments. The results showed that the POME application had a significant effect on total microbes, soil respiration and cation exchange capacity. The total microbes, C-organic, soil respiration, cation exchange capacity and alkaline saturation on the POME application land were 34.7 x 10−6 CFU ml-1, 2.16%, 1.4 mg C (CO2), 11.1 cmol kg−1 and 40.75%, while on land without POME applications were 1.63 x 10−6 CFU ml−1, 2.32%, 0.52 mg CO2, 7.59 cmol kg−1, and 70.63%. Soil sampling at a distance of 0, 100 cm, 200 cm, 300 cm and 400 cm from the palm oil tree towards the POME application trench had a significant effect on total microbes and soil respiration. The highest of total microbes and soil respiration at 0 cm from oil palm trees were 34.07 x 10−6 CFU ml−1 and 1,14 mg C (CO2). The interaction between soil sampling from the application land and without the application land with the sampling distance treatment from palm oil trees had a significant effect on the soil total microbes parameters. The conclusions of this research were; the application of POME with BOD 180 mgL-1 and COD 593 mgL-1 on palm oil plantations can increase the total soil microbes, soil respiration and cation exchange capacity but did not increase C-organic and alkaline saturation. The closer the application to the palm oil plant rhizosphere, the higher the distribution and microbial activity.