Soil Water in Different Management Systems of Coffee-Pine Agroforestry and Its Relation to Coffee Bean Yields

Coffee-pine agroforestry is a common land use system in Indonesia, that provides several benefits, including increased soil fertility, biodiversity, and economic returns. However, the management of coffee-pine agroforestry systems can significantly impact on soil water dynamics, affecting coffee bean yields. This study investigated the effects of different management systems on soil water dynamics and coffee bean yields in a coffee-pine agroforestry system in UB Forest, Malang East Java, Indonesia. Five different management systems were evaluated: (i) no management, (ii) pruned coffee with no fertilizer, (iii) pruned coffee with added organic fertilizer, (iv) pruned coffee with added organic-inorganic mix fertilizer, with a planting distance of pine trees of 3 x 2 m, and (v) pruned coffee with added organic-inorganic mix fertilizer under pine trees with a planting distance of 6 x 2 m. The soil water dynamics were measured at depths of 0-0.2 m with a soil moisture sensor and connected with a data logger measured within a year, started in April 2022. Coffee bean yield was measured with 100 coffee plants, then converted to production on ton ha-1. The results showed that the different management systems significantly impacted soil water dynamics and coffee bean yields. The combination of pruning and fertilization is a promising management strategy for increasing coffee bean yields in coffee-pine agroforestry systems. The consequent better growth of coffee plants impacts increasing soil water extraction. This study provides valuable insights for farmers and forest managers who are interested in improving the productivity of coffee-pine agroforestry systems and conserving soil water or sometimes needing water addition through irrigation.