Impact of Palm Oil By-Products Application to Earthworm Populations and Soil Chemical In Oil Palm Plantation

Abstract

Palm oil mill has by-products from processing fresh fruit bunch such as empty fruit bunch and fruit fiber that benefits oil palm plantation. The aim of this research was to observe earthworms population and soil chemical properties after the application of palm oil by-products. This research was conducted in Pantai Harapan Estate PT Bumitama Gunajaya Agro, Central Kalimantan from July 2020-May 2021. The organic matter was used in this study were empty bunch, empty bunch compost, and pressed fruit fiber, applied in an oil palm circle in two different soil types. The earthworms population was observed before and six months using a square sampling size 1 m x 1 m at a depth of 0,15 m. The earthworms population after six months with organic application both in dystrudepts and haplohumods range from 46 to 119 individuals/m2. Earthworms population increased 22,17% and 71,33% after six month, compared to control decrease 48,21% and 68,51% in haplohumods and dystrudepts respectively. Soil chemical properties such as C-organic, total P, and K are significantly different after organic application compared to control both in haplohumods and dystrudepts. Thus, the application of organic matter is able to increase the earthworms population and improve soil chemical properties in oil palm plantations.