Kajian Laju Infiltrasi pada Tegakan Mahoni, Jati Putih, Pulai dan Jabon di Arboretum Universitas Sumatera Utara

Abstract

Infiltration is the process of water entering the soil from the surface and plays an important role in the hydrological cycle. The Arboretum of Campus 2, University of Sumatera Utara, Bekala has various tree stands, including mahogany, white teak, pulai, and jabon. These stands have the potential to increase the infiltration rate and reduce runoff. This study aims to analyze the infiltration rate in various tree stands in the Arboretum of Campus 2, University of Sumatera Utara Bekala, as well as the relationship between soil physical properties and infiltration rate. Infiltration rate measurements in the field were carried out using a double ring infiltrometer. The Horton Model and the Kostiakov Model were used to analyze the infiltration rate of each stand. The results of the models were then tested using the Nash Sutcliffe Efficiency (NSE) and Root Mean Square Error (RMSE) tests. The results showed that the highest average infiltration rate was found in the jabon stands, namely 1.28 cm/hour, while the lowest average infiltration rate was found in the mahogany stands, namely 0.65 cm/hour. Organic matter content and sand fraction are the factors that most strongly influence the infiltration rate, with a positive correlation to the maximum infiltration capacity (Fc) and the initial infiltration rate. The NSE and RMSE test results show that the Horton Model provides a better infiltration rate prediction value than the Kostiakov Model, with a lower RMSE value and an NSE closer to one.