Samenvatting

This thesis examines how oil palm plantation characteristics affect the presence and biomass of earthworms in Malaysia. The research was carried out across 228 plots in Selangor and Negeri Sembilan. Results show that industrial plantations host more earthworms, while smallholder plantations support heavier individuals. Grazing as a weed management method led to higher earthworm numbers than chemical weeding. In addition, interplanting rows contained more earthworms than harvesting paths, due to better soil conditions and higher organic matter. Earthworms proved to be important bioindicators of soil health and sustainability. The study highlights the importance of proper soil management and sustainable agricultural practices to maintain biodiversity within the palm oil sector.