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All Journal Geo Media: Majalah Ilmiah dan Informasi Kegeografian LaGeografiA Jurnal Geografi : Media Informasi Pengembangan dan Profesi Kegeografian Majalah Geografi Indonesia Journal of Degraded and Mining Lands Management
Riyanto, Indra Agus
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Agriculture, Biological Sciences & Forestry Humanities Biochemistry, Genetics & Molecular Biology Earth & Planetary Sciences Education Physics Social Sciences Other

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Dampak Siklon Tropis Savannah pada Karst Window Kalinongko, Karst Gunungsewu, Kabupaten Gunungkidul, Indonesia Riyanto, Indra Agus; Cahyadi, Ahmad; Ramadhan, Fajri; Naufal, Muhammad; Widyastuti, Margaretha; Adji, Tjahyo Nugroho
Jurnal Geografi : Media Informasi Pengembangan dan Profesi Kegeografian Vol 17, No 1 (2020): January
Publisher : Universitas Negeri Semarang

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.15294/jg.v17i1.21419

Abstract

Siklon Tropis Savannah melewati Daerah Istimewa Yogyakarta pada tanggal 17 Maret 2019. Curah hujan yang disebabkan oleh Siklon Tropis Savannah terekam pada stasiun Geofisika badan meteorologi, klimatologi dan Geofisika (BMKG) Yogyakarta sebesar 170,6 mm/hari dan terekam pada Stasiun Cuaca Beton milik Kelompok Studi Karst Fakultas Geografi Universitas Gadjah Mada sebesar 78,3 mm/hari. Curah hujan menunjukkan bahwa siklon tropis ini menyebabkan terjadinya hujan ekstrim. Siklon Tropis Savannah menyebabkan bencana banjir di beberapa wilayah Daerah Istimewa Yogyakarta salah satunya terjadi di Karst Window Kalinongko, Kawasan Karst Gunungsewu, Kabupaten Gunungkidul. Karst Window Kalinongko terdampak banjir dari meluapnya sungai bawah tanah. Proses terjadinya banjir di Karst Window Kalinongko disebabkan oleh aliran air yang melebihi kapasitas pengaliran dari lorong konduit pada sungai bawah tanah. Sistem konduit yang penuh kemudian meluap ke permukaan dan menggenang pada bagian dolin di sekitar Karst Window Kalinongko. Waktu surut banjir airtanah di Karst Window Kalinongko adalah selama 10 hari. Banjir Siklon Tropis Savannah yang menggenang memiliki volume sebesar 4.894.258 m3, luasan area terdampak seluas 13.723 m2, dan ketinggian genangan 6 meter. Dampak genangan banjir airtanah yang disebabkan Siklon Tropis Savannah di Karst Window Kalinongko merendam lahan sawah seluas 10.586 m2 dan perkebunan seluas 3.137 m2.
Kajian Daerah Sulit Air di Kabupaten Kulon Progo Daerah Istimewa Yogyakarta Hendrayana, Heru; Riyanto, Indra Agus; Nuha, Azmin
LaGeografia Vol 19, No 2 (2021): Februari
Publisher : UNIVERSITAS NEGERI MAKASSAR

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (1406.468 KB) | DOI: 10.35580/lageografia.v19i2.15345

Abstract

Water-scarce areas can be identified from geology, meteorology, water installations, and drought conditions in the area. All of these aspects can be found in Kulon Progo Regency. The aim of this research is to identify water scarcity areas in Kulon Progo Regency and to determine priorities areas for building up some deep wells. There are four parts of the method that used in this study, there are water scarcity areas from the geological aspect interpreted based on geological, hydrogeological, and groundwater basin  maps, meteorological aspects using the water balance method and drought index, distribution water installation analyzed from PDAM data, and drought information collection from interview. Based on a study on the identification of water scarcity areas in Kulon Progo Regency with geological and hydrogeological parameters, meteorological drought, PDAM and SPAM, and Interviews, it was found that 181 hamlets that having water-scarce in 35 villages in 11 sub-districts both covering areas that can be drilled and cannot be drilled. The number of water-scarce areas selected for groundwater drilling is 104 hamlets. The number of water scarcity areas in 1st priority is 37 hamlets, there are 21 helmets for 2nd priority, and 46 hamlets for 3rd priority.
Dampak Siklon Tropis Savannah Terhadap Karakteristik Hidrogeokimia Aliran pada Mata Air Guntur, Kawasan Karst Gunungsewu Ramadhan, Fajri; Riyanto, Indra Agus; Cahyadi, Ahmad; Naufal, Muhammad; Widyastuti, M; Adji, Tjahyo Nugroho
Jurnal Geografi : Media Informasi Pengembangan dan Profesi Kegeografian Vol 18, No 2 (2021): In progress [July 2021]
Publisher : Universitas Negeri Semarang

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.15294/jg.v18i2.30293

Abstract

Tropical Cyclones often occur in Indonesia and have disastrous impacts. Until now, no research has focused on time series data related to groundwater discharge and chemistry due to tropical cyclones. Therefore, this study aims to analyze and compare the characteristics of the hourly time series, both discharge and chemistry of the Guntur karst springs. Guntur Spring was affected by the tropical cyclone of Savannah on March 17, 2019. The method used in this study consisted of two parts, namely the analysis of the discharge and chemistry of Guntur Spring. Discharge analysis was performed by correlation test with rain intensity. Chemical analysis was carried out using the Minister of Health Regulation No. 90 of 2002 and expert standards. Other chemical analyzes were performed using a triangular piper, rectangular piper, and stiff diagram of the parameters Na+, K+, Ca2+, Mg2+, SO42-, Cl-, and HCO3-. The results of the relationship between discharge and rain intensity are directly proportional and increase significantly during a cyclone. The results of analysis of the Guntur Springs during Tropical Cyclone Savannah, all parameters are in accordance with the quality standard. In addition, there was a reduction in ion content due to the dilution process of Ca2+, Mg2+, Cl-, HCO3-., DHL, and pH ions compared to non-cyclone, Beton Resurgence, and Gremeng Resurgence ions. The chemical results when the cyclone is different compared to non-cyclone, Gremeng Resurgence and Beton Resurgence with a characteristic decrease in ionic content.
Karakteristik Hidrogeologi dan Hidrogeokimia DAS Tempuran Lereng Barat Kompleks Gunungapi Bromo-Tengger Hendrayana, Heru; Riyanto, Indra Agus; Nuha, Azmin
Majalah Geografi Indonesia Vol 38, No 1 (2024): Majalah Geografi Indonesia
Publisher : Fakultas Geografi, Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22146/mgi.89369

Abstract

Abstrak Lereng bagian barat Gunungapi Bromo meiliki peranan penting dalam penyediaan air untuk masyarakat disekitarnya. Penggunaan air tanah cukup intensif baik domestik, pertanian, dan industri pada lereng bagian barat Gunungapi Bromo. Lerang bagian barat bagian barat Gunungapi Bromo belum pernah dilakukan kajian detail baik potensi, kualitas, dan imbuhan air tanah. Kajian tersebut di tujukan untuk mengetahui kondisi air tanah di lereng bagian barat Gunungapi Bromo supaya dapat dimanfaatkan secara berkelanjutan. Metode yang digunakan dalam penelitian ini terdiri atas pengamatan batuan, pengukuran muka air tanah, pengukuran kimia air tanah TDS, pH, EC, dan suhu, analisis geokimia berdasarkan diagram piper, diagram fingerprint, dan diagram kurlov, analisis isotop asal usul air tanah dan imbuhan air tanah. Litologi di area kajian terdiri atas endapan pasir kerikilan, endapan pasir, batupasir, konglomerat, breksi laharik, lapilli tuff, tuff, breksi, dan lava andesit. Nilai TDS, pH, Suhu, dan EC di DAS Tempuran semakin meningkat dari hulu ke hilir. Pola aliran air tanah pada DAS Tempuran secara umum mengalir dari arah selatan menuju utara. Satuan lava dan breksi andesit merupakan akuifer, lava andesit dan breksi andesit merupakan akuiklud, jatuhan piroklastik merupakan akuifer, dan tuf dan lapilli tuf merupakan akuitard. Tipe air tanah pada DAS Tempuran didominasi oleh tipe kalsium bikarbonat (diagram piper) dan kalsium magnesium bikarbonat (diagram kurlov), dan diagram fingerprint terdapat 3 sistem air tanah. Sampel air tanah di DAS Tempuran keseluruhan berasal dari air meteorik. Imbuhan air tanah di DAS termpuran berasal dari elevasi 430-805 mdpl. Daerah imbuhan air tanah terdapat di Kecamatan Pasepran, Puspo, dan Tutur. Air tanah di area kajian secara kualitas dan kuantitas tergolong sangat baik.Abstract The western slopes of Mount Bromo have an important role in providing water for the surrounding community. Groundwater use is quite intensive, both domestically, agriculturally, and industrially, on the western slopes of Mount Bromo. The western slope of Mount Bromo has never had a detailed study of its potential, quality, and groundwater recharge. The study was aimed at determining the condition of groundwater on the western slopes of Mount Bromo so that it can be used sustainably. The methods used in this research consist of rock observations, measurements of groundwater levels, measurements of groundwater chemistry (TDS, pH, EC, and temperature), geochemical analysis based on Piper diagrams, fingerprint diagrams, and Kurlov diagrams, isotope analysis of the origin of groundwater, and recharge. groundwater. The geology in the study area consists of gravelly sand deposits, sandstone, conglomerate, laharic breccia, lapilli tuff, andesite breccia, and andesitic lava. The TDS, pH, temperature, and EC values in the Tempuran watershed increase from upstream to downstream. The groundwater flow pattern in the Tempuran watershed generally flows from south to north. Units of lava and andesite breccia are aquifers; andesite lava and andesite breccia are aquicludes; pyroclastic falls are aquifers; and tuff and tuff lapilli are aquitards. The groundwater types in the Tempuran watershed are dominated by calcium bicarbonate (Piper diagram) and calcium magnesium bicarbonate (Kurlov diagram), and in the fingerprint diagram, there are 3 groundwater systems. The entire groundwater sample in the Tempuran watershed comes from meteoric water. Groundwater recharge in the purest watershed comes from an elevation of 430–805 meters above sea level. Groundwater recharge areas are in the Pasepran, Puspo, and Tutur Districts. The study area’s groundwater quality and quantity are rated as very good
Kesesuaian Lahan Untuk Tanaman Kopi di Area Sekitar Danau Toba Riyanto, Indra Agus; Hendrayana, Heru; Sambodo, Ahmad Priyo; Widyaningsih, Yuli; Jayanto, Galih Dwi
Majalah Geografi Indonesia IN PROGRESS ISSUE
Publisher : Fakultas Geografi, Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22146/mgi.94042

Abstract

Abstrak Youngest Toba Tuff (YTT) merupakan material pembentuk tanah andosol yang dominan di Kaldera Toba. YTT memiliki karakteristik yang berbeda dengan tanah andosol hasil dari material gunungapi aktif. YTT tersusun atas material ignimbrite tebal yang kaya akan batuapung. Material YTT tersebut tergolong subur untuk berbagai jenis tanaman yang ada pada Kaldera Toba bagian dalam. Kajian kesesuaian lahan untuk peruntukan tanaman tertentu belum pernah dilakukan di Kaldera Toba bagian dalam. Oleh karena itu penelitian ini bertujuan untuk mengkajian kesesuaian lahan untuk tanaman kopi. Metode yang digunakan adalah weight matching dengan konsep faktor terberat menjadi penentu klasifikasi utama kelas kesesuaian lahan. Unit analisis yang digunakan dalam penelitian ini adalah sistem lahan. Karakteristik klimatologi DTA Danau Toba sesuai untuk tanaman kopi dengan curah hujan 2.000-2.500 mm/tahun, bulan kering < 2 bulan, suhu 18,4-19,4°C, dan kelembaban 84-91%. karakteristik fisik tanah DTA Danau Toba Toba dominan termasuk sesuai (S2) dengan bahan organik (BO) 1-2%, tekstur geluh pasiran, dan permeabilitas agak cepat. Kelas S2 terdapat pada sistem lahan MBI, SAR, BTA, dan BTG, dan TWI. Kelas tidak sesuai (N) terdapat pada sistem lahan ASA dan BTG dengan kedalaman tanah tipis (<25cm) dan tekstur lempung liat. Kelas kesesuaian lahan sesuai marginal (S3) terdapat pada sistem lahan BBG, BPD, BPP, SLK, dan TBG. Kelas kesesuaian lahan sangat sesuai (S1) terdapat pada sistem lahan UBD dan SLK dengan dengan berat volum (0,8-1,1 gram/cm3), kedalaman tanah (75-100) cm, BO (>3%), permeabilitas cepat, dan tekstur geluh pasiran. Formasi YTT termasuk dalam kelas kesesuaian lahan S1 dan S2 untuk tanaman kopi, sedangkan material endapan danau, dan lava termasuk kelas S3 dan N untuk tanaman kopi.  Abstract Youngest Toba Tuff (YTT) is the dominant andosol soil-forming material in the Toba Caldera. YTT has different characteristics from the andosole soil resulting from active volcanic material. YTT is composed of thick ignimbrite material that is rich in pumice. YTT material belongs fertile to various kinds of plants that exist on the Toba Caldera inside. Soil suitability studies to have never been carried out in the inner Toba caldera. Therefore, this study aims to examine the suitability of the soil for coffee crops. The method used is weight matching with the concept of the heaviest factor being the primary determinant of the classification of the land suitability class. The unit of analysis used in this study is the land system. Climate Characteristics Toba Caldera is suitable for coffee plants with rainfall of 2,000-2.500 mm/year, dry months < 2 months, temperature 18,4-19,4°C, and humidity 84-91%. Dominant Toba Caldera soil physical characteristics include matching (S2) with organic material (BO) 1-2%, sandy loam texture, and relatively fast permeability. Class S2 is available on MBI, SAR, BTA, and BTG, and TWI land systems. The class non-conform (N) is found on ASA, BTG land systems with thin soil depths (<25cm) and clay texture. Marginal soil compatibility classes (S3) are found on BBG, BPD, BPP, SLK, and TBG soil systems. Very suitable soil (S1) is present on UBD and SLK soil system with volume weights (0.8-1,1 grams/cm3), soil deep (75-100) cm, BO (>3%), fast permeability, and sandy loam textures. YTT material belongs to the soil suitability classes S1 and S2 for coffee plants, while lake sediment and lava are classified in the classes S3 and N for coffee plantations. 
Groundwater quality assessment in different volcanic rocks using water quality index in the tropical area, Indonesia Hendrayana, Heru; Riyanto, Indra Agus; Ismayuni, Novia; Nuha, Azmin; Muhammad, Azwar Satrya; Fadillah, Arif
Journal of Degraded and Mining Lands Management Vol. 11 No. 4 (2024)
Publisher : Brawijaya University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.15243/jdmlm.2024.114.6225

Abstract

Groundwater is the main water source that is most widely used in the world, one of which is in Indonesia. One of the uses of groundwater is for consumption needs. Therefore, the groundwater used should have good water quality. For this reason, this study aimed to determine groundwater quality in Indonesia during the dry season and make recommendations for groundwater management policies. A total of 211 groundwater samples taken from springs, drilled wells, and dug wells spread across volcanic areas on the islands of Sumatra, Java, Bali, and Sulawesi were collected to test their quality in this research. The method used in this research consisted of 4 analyses: WHO threshold analysis, Piper Diagram, Water Quality Index (WQI), and statistical correlation and regression. Based on the analysis, it was discovered that 47 K+ samples, 1 Na+ sample, 5 Ca2+ samples, 1 Cl- sample, 115 HCO3- samples, 3 TDS samples, and 3 pH samples exceeded WHO standards. The results of the Piper triangle diagram analysis showed that the majority of groundwater in Indonesia falls into the Unpolluted Groundwater classification (categories D and G), and the results of the WQI analysis also showed that 98% of the groundwater in Indonesia analyzed falls into the excellent and good water categories. The results of statistical analysis of the parameters K+, Na+, Mg2+, Ca2+, SO42-, Cl-, HCO3-, TDS, and pH showed that all these parameters are strongly and positively correlated with the WQI value.
The decline in water level and discharge of Lake Toba of North Sumatera, Indonesia, affected by land degradation Riyanto, Indra Agus; Hendrayana, Heru; Yuli Widyaningsih; Jayanto, Galih Dwi; Azmin Nuha; Sabdo Sumartono
Journal of Degraded and Mining Lands Management Vol. 12 No. 2 (2025)
Publisher : Brawijaya University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.15243/jdmlm.2025.122.7123

Abstract

Lake Toba is one of the prioritized conservation lakes in Indonesia, crucial for domestic needs, tourism, fisheries, agriculture, and power generation. However, Lake Toba’s water levels and discharge have declined in recent decades. This study aimed to enhance water recharge and the water level of Lake Toba through hydrological modeling using the SWAT analysis and regional and specific conservation measures. The SWAT analysis utilized input data, including climate, soil, geomorphology, land use, and hydrology, to generate both existing and post-conservation water balance models. Conservation methods were categorized into civil engineering and vegetative approaches. Vegetative conservation techniques included agroforestry and MPTS (Multi-Purpose Tree Species), while civil engineering methods encompassed terracing, trenching, and infiltration wells. Regional conservation focused on land use plant types, while specific conservation involved detailed classification of the Lake Toba watershed by slope class, plant type, and land use. The analysis revealed significant land use changes in the Lake Toba catchment area, with dry fields increasing from 72,961 ha to 125,000 ha, a decrease in water level from 905 to 903 m above sea level, and a reduction in discharge from 180 m³/s to 125 m³/s. SWAT analysis shows that the existing inflow to Lake Toba is 131 m³/s (with 78% accuracy), with potential increases to 250 m³/s due to regional conservation and 180 m³/s due to specific conservation. Conservation efforts have also improved discharge rates across 39 sub-watersheds of Lake Toba, both monthly and annually.
In-depth Assessment of Groundwater Quality in East Java Industrial Areas to Maintain the Sustainability of Groundwater Utilization Hendrayana, Heru; Riyanto, Indra Agus; Nuha, Azmin
Journal of Degraded and Mining Lands Management Vol. 12 No. 3 (2025)
Publisher : Brawijaya University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.15243/jdmlm.2025.123.7649

Abstract

With its abundant groundwater potential, East Java faces a growing risk of contamination due to rapid industrial growth. This study assessed groundwater quality in four regional groundwater basins (GWB) using the Water Quality Index (WQI), water quality standard comparison, Piper diagram, and hydrogeochemical ion analysis. The WQI analysis revealed that 59% of the samples were classified as excellent and good for consumption, predominantly found in volcanic, river alluvial, and limestone hill areas. In comparison, 11% were unsuitable for consumption due to contamination, particularly near coastal, industrial, and agricultural zones. The Piper diagram showed that most groundwater samples were unpolluted, reflecting the natural interaction between groundwater and surrounding lithology. However, ion standard comparison identified samples exceeding acceptable ion levels, and ion correlation analysis confirmed contamination from industrial, agricultural, anthropogenic, and municipal wastewater activities. These findings highlight the need for targeted groundwater management, particularly in areas vulnerable to contamination.
Studi Pendahuluan Karakteristik Hidromorfologi Danau Laut di Kawasan Karst Mawasangka Timur, Buton Tengah, Sulawesi Tenggara Haryono, Eko; Putra, Rakhmat Dwi; Hakim, Arief Abdurrahman; Siswanto, Aries Dwi; Satrio, Fahry Adhi; Riyanto, Indra Agus; Cahyadi, Ahmad
Geo Media: Majalah Ilmiah dan Informasi Kegeografian Vol. 23 No. 1 (2025): Geo Media: Majalah Ilmiah dan Informasi Kegeografian
Publisher : Universitas Negeri Yogyakarta

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.21831/gm.v23i1.78909

Abstract

Danau laut memiliki keunikan baik secara morfometri dan proses terbentuknya.  Penelitian ini bertujuan menganalisis hidromorfologi danau laut di Kawasan Karst Mawasangka Timur, Kabupaten Buton Tengah, Sulawesi Tenggara. Analisis hidromorphologi meliputi L Max, B max, B mean, SI, orientasi danau laut, elevasi dan jarak dari pantai.  Analisis hidromorfologi dilakukan dengan pengukuran langsung di lapangan, pengukuran dengan underwater drone, dan pengukuran melalui data citra penginderaan jauh dan peta sekunder. Danau laut yang dikaji meliputi  Oe Mamba Kecil, Oe Mamba Besar, Pasi Bungi, Air Wali, dan Wa Piho Piho. Hasil perhitungan L max danau laut di area kajian berkisar 39 – 1.028 m, B max (30 – 685 m), B mean (21 – 487 m), SI (155,62 – 2.951 m2), DI (0,381 – 0,425 m), Orientasi (NE-SW, N-S, dan E-W), elevasi (2 – 35 mdpal), jarak terhadap pantai (37 – 785 m) dan kedalaman max (10 – 57,8 m). Nilai morfometri danau laut di Buton Tengah Sulawesi Tenggara memiliki rentang yang sama dengan danau laut tropis lain di Kalimantan, Papua, Filipina, dan Kroasia.
Co-Authors Ahmad Cahyadi **) Aries Dwi Siswanto Arif Fadillah Azmin Nuha Eko Haryono Hakim, Arief Abdurrahman Heru Hendrayana Ismayuni, Novia Jayanto, Galih Dwi M Widyastuti Margaretha Widyastuti Muhammad Naufal, Muhammad Muhammad, Azwar Satrya Nuha, Azmin Putra, Rakhmat Dwi Ramadhan, Fajri Sabdo Sumartono Sambodo, Ahmad Priyo Satrio, Fahry Adhi Tjahyo Nugroho Adji Widyaningsih, Yuli Yuli Widyaningsih