Soil microbial populations of several land use types in Makbon District, Sorong Regency, Indonesia

Degradation of soil function can damage the surrounding ecosystem. Soil fertility is important to plant growth because it is the source of nutrition. One of the factors determining soil fertility is the soil's biological aspects. The study aims to identify the soil microorganism population in the area with the potential for agriculture in Makbon District. The research steps included sampling, media preparation, preparation of dilution series, isolation, and soil microorganism calculation. Based on the land usage, samples K۱, M۱, and M۳ were mapped as primary forests; K۲ was a banana farm; B۱, K۳, M۲, and T۱ were mixed farms; while T۲ and T۳ were for horticulture. The findings show that based on the calculation of the total bacteria using the TPC model, the biggest population was found in the mixed farms among various land usages. T۲ exhibited  the biggest number of bacteria (۱,۲ × ۱۰۵ CFU mL-۱) compared to other samples, followed by T۱ with the total bacteria of ۱.۱ × ۱۰۵ CFU mL-۱ and M۲ with the total bacteria of ۱.۰ × ۱۰۵ CFU mL-۱. On the other hand, sample K۳ displayed the biggest number of fungi colonies, ۱.۰ × ۱۰۳ CFU mL-۱. The biggest number of phosphate-solubilizing bacteria colonies were found in Sample B۱, which was ۱.۸ × ۱۰۵ CFU mL-۱. Furthermore, the biggest number of Nitrobacter colonies was found in sample M۳, which was ۱.۲ × ۱۰۴ CFU mL-۱. The study is expected to provide a description and information about the ground microbe population in agroforestry and mixed farms to be considered in the next studies.

Keywords:

Compost , waste , land potential , Organic fertilizer