ARTIFICIAL TRACER TEST FOR CHARACTERISATION AND CONSERVATION OF KARST WATER IN JONGGRANGAN KARST, JAVA ISLAND, INDONESIA

Anjani, Kiskendo, and Mudal springs are essential in the Jonggrangan Karst region, Java Island, Indonesia, because of their perennial flow as the primary domestic water source for residents living in this region and recharged by the surface flow or underground river. This study aims to describe the underground system connectivity and transport parameters of the three springs through a tracer test and estimate the catchment area using the water balance approach. Besides, proposed conservation actions for each catchment spring are carried out by considering the transport parameters from the tracer test and karstification degree values from previous studies. Tracer test results show that several subsurface flow systems with single-conduit character were found in the study area. The results of the water balance approach show that Anjani Cave has a catchment area of 0.8km2, while the Kiskendo and Mudal Caves are 3.69 km2 and 1.71km2, respectively. Recommended conservation actions include the management of solid and liquid wastes before being discharged, restrictions on upstream land-use conversion and arrangements for the use of pesticides (Anjani catchment). They were also planting pioneer trees and making terraces that effectively prevent erosion (Kiskendo catchment), while in the catchment of Mudal Springs (characterised by diffused-recharge typed), it is necessary to maintain the forest not converting it into rice-field or mixed-garden. © 2021. All Rights Reserved.