Temporal Variations of Baseflow Contribution to Epikarst spring Discharge in Gunungsewu Karst Area, Indonesia

Abstract

Flow moving slowly (infiltration), and known as steady flow or baseflow is the only supplier of water in underground flows in the form of karst fields during the dry season. Certainly, the character contribution of this flow plays a major role in supporting the supplier of clean water. Understanding related to the character of baseflow in detail has a very high urgency to be studied. This Research aims to do a temporal analysis of baseflow contributions on epikarst water springs in Gunungsewu Karst Area, Indonesia. The research takes place in Guntur Springs that occupy the hydrogeological subsystem. Data used in this Research includes flow data from Guntur Springs for one year. The method used in this Research is automated base flow separation by digital filtering. Results of the analysis show that baseflow contribution in Guntur Springs are between 79.57% and 93.96%.

Temporal Variation of Tropical Karst Groundwater Suitability for Irrigation in Gremeng Resurgence, Gunungsewu Karst Area, Indonesia

“…In other words, hazards that originate from sodium presence and electrical conductivity in the study area are relatively low. Such low electrical conductivity is attributable to the relatively long distance to seawater sources (little to no possibility of intrusion), relatively small catchment (13.25 km 2 ), allogenic recharge that responds quickly to rain (allowing short contact of water to rocks), and relatively developed dissolution channels [27,28,29]. High electrical conductivity has the same impact as high sodium content.…”

Geochemical of Karst Water in the Western part of Gunungkidul District Area

“…Groundwater emerges in several places as springs of reef limestone aquifers, supported by intergrain, fractures, and channels porosities. Groundwater and surface water are colourless (46 -350 TCU) and relatively clear (3)(4)(5)(6)(7)(8)(9)(10)(11)(12)(13)(14)(15)(16)(17)(18)(19) with a pH of 6.8 -8.1 and TDS of 76 -308 ppm. Groundwater shows Ca -bicarbonate and Ca, Mgbicarbonate types, whereas dolines water has Ca, Mgbicarbonate types.…”

“…The low flow rate is one of the characteristics of the emergence of springs in the area. During the rainy season, the direct flow has a greater contribution to reducing the proportion of the baseflow component [10].…”

Dampak Siklon Tropis Savannah pada Karst Window Kalinongko, Karst Gunungsewu, Kabupaten Gunungkidul, Indonesia

“…Kedua mataair tersebut memiliki keterhubungan sistem konduit di Kawasan karst dengan Underground River kalinongko (Cahyadi, dkk., 2018a;Riyanto, 2019). Sistem konduit adalah sistem hidrologi airtanah dikawasan karst yang berupa lorong hasil pelarutan dengan ukuran diameter minimal 10 mm (Cahyadi, 2014;Cahyadi dan Agniy, 2016 Naufal, et al, 2019;Ramadhan, dkk., 2019). Ketinggian tinggi muka air mataair Guntur saat siklon 57 cm dan pengukuran tertinggi sebelumnya sebesar 30 cm saat musim penghujan.…”

“…Proses penurunan genangan banjir Siklon Tropis Savannah di Karst window Kalinongko butuh waktu 10 hari karena sistem aliran yang dominan berupa diffuse, sedangkan drainase konduit sudah berkembang tetapi belum lanjut (Haryono dkk., 2017;Naufal, et al, 2019;Rahmawati, 2019;Ramadhan, dkk., 2019). Sistem diffuse merupakan aliran air melalui rongga antar butir batuan gamping.…”