Infiltration rate under the most dominant tree stands at the University Green Space: Swietenia macrophylla, Mimusops elengi, and Polyalthia longifolia

Abstract

Abstract Infiltration is crucial for determining how much rainfall enters the soil and how much becomes runoff. The Universitas Sumatera Utara (USU) Campus Medan is one of the green campuses with diverse tree species. The ability of tree stands on the USU Campus Medan to absorb water needs to be studied for flood mitigation. This study aims to analyze the infiltration rate under the most dominant tree stands at the University Green Space: Swietenia macrophylla (mahagony), Mimusops elengi (tanjung), and Polyalthia longifolia (glodokan tiang) using the Horton method. The infiltration measurement uses double ring infiltrometer. The infiltration data will process using Horton Method. The results show that the infiltration rate under mahogany and tanjung stands are included to medium infiltration. While the infiltration rate under glodokan tiang stand is included to fast infiltration. The correlation test on mahogany, tanjung, and glodokan tiang stands indicate a strong correlation between the actual infiltration rate with Horton’s infiltration rate and have a positive trend, so it can be concluded that Horton method can be used to estimate the infiltration rate in each stand.