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KARAKTERISTIK SEDIMEN MELAYANG DAN SEDIMEN DASAR PADA SUNGAI BOMPON, SUB DAS BOMPON, KABUPATEN MAGELANG, JAWA TENGAH Maqdan, Maola; Yogafanny, Ekha; Sungkowo, Andi; Setiawan, Muhammad Anggri; Sartohadi, Junun
Jurnal Mineral, Energi dan Lingkungan Vol 3, No 1 (2019): Juni
Publisher : Fakultas Teknologi Mineral, Universitas Pembangunan Nasional (UPN)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.31315/jmel.v3i1.2893

Abstract

Proses geomorfologi seperti erosi dan longsor sangat aktif terjadi di Sub DAS Bompon yang berada di Kabupaten Magelang, Jawa Tengah. Material yang tererosi tersebut tersedimentasi di Sungai Bompon. Material sedimen yang berada pada Sungai Bompon berasal dari tanah permukaan yang tererosi, erosi tebing sungai, dan erosi dasar sungai. Karakteristik sedimen yang berada di Sungai Bompon perlu diketahui guna mengetahui upaya pengelolaan daerah aliran sungai terpadu. Tujuan penelitian ini untuk menganalisis karakteristik sedimen melayang dan sedimen dasar pada sungai Bompon pada bagian hulu, tengah dan hilir. Metode yang digunakan dalam penelitian ini yaitu metode survei, metode pemetaan, metode analisis laboratorium dan metode matematis. Hasil penelitian menunjukan bahwa debit muatan sedimen melayang pada bagian hulu sungai rata-rata sebesar 55,322 ton/tahun dengan hubungan antara debit aliran dan debit muatan sedimen melayang yang dirumuskan dalam Qs = 9,12119 Q -0,12828 dengan r (korelasi) = 0,9768. Debit muatan sedimen dasar pada hulu sungai rata-rata sebesar 0,323 ton/tahun. Pada bagian tengah sungai, debit muatan sedimen melayang memiliki rata-rata sebesar 945,570 ton/tahun dengan hubungan antara debit aliran dan debit muatan sedimen melayang dapat dirumuskan dalam Qs = 23,9113 Q -0,58204 dengan r (korelasi) = 0,98178. Debit muatan sedimen dasar pada bagian tengah sungai rata-rata sebesar 2,077 ton/tahun. Pada bagian hilir sungai, debit muatan sedimen melayang memiliki rata-rata sebesar 8297,002 ton/tahundengan hubungan antara debit aliran dan debit muatan sedimen melayang dapat dirumuskan dalam Qs = 42,3715 Q -1,14840 dengan r (korelasi) = 0,95373 dan debit muatan sedimen dasar yang dihasilkan rata-rata sebesar 5,975 ton/tahun.
Geospatial Assessment of Coseismic Landslides in Baturagung Area Saputra, Aditya; Sartohadi, Junun; Hadmoko, Danang Sri; Gomez, Christopher
Forum Geografi Vol 29, No 2 (2015): December 2015
Publisher : Universitas Muhammadiyah Surakarta

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.23917/forgeo.v29i2.693

Abstract

Java, the most densely populated island in Indonesia, is located on top of the most seismically active areas in Southeast Asia: the Sunda Megathrust. This area is frequently hit by strong earthquake. More than 3,300 M>5earthquakesoccurred between 1973-2014. The wide range of mountainous areas and high intensity of rainfall, make several part of the island one of the most exposed regions for coseismic landslides such as Baturagung area, the Southeast mountainous area of Yogyakarta Province. An integrated method between RS and GIS was used to conduct the vulnerability assessment due to the lack of the site specific slope instability analysis and coseismic landslides data. The seismic zonation of Baturagung area was obtained based on the analysis of Kanai attenuation. The geologic information was extracted using remote sensing interpretation based on the 1:100,000 geologic map of Yogyakarta and geomorphologic map of Baturagung area as well. The coseismic landslide hazard assessment has been estimated using scoring analysis in the GIS platform proposed by Mora and Vahrson (1993) with several modification. The accomplished coseismic landslide hazard map shows medium hazard coverage in the eastern areas, in the upper slope of Baturagung area, which consists of Semilir Formation. The result provides a distinct description of coseismic landslides hazard distribution in Batuaragung area. However, it should only be the preliminary assessment of the site specific investigation especially on valuable area or asset. 
UTILIZATION OF SOIL FUNCTION INFORMATION FOR ASSESSING SOIL QUALITY OF RICE FIELD IN THE QUATERNARY-TERTIARY VOLCANIC TRANSITIONAL ZONES IN CENTRAL JAVA Prayitno, Ajun; Sartohadi, Junun; Nurudin, Makruf
SAINS TANAH - Journal of Soil Science and Agroclimatology Vol 16, No 2 (2019): December
Publisher : Universitas Sebelas Maret

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (1430.954 KB) | DOI: 10.20961/stjssa.v16i2.35492

Abstract

Soil quality information of the rice field in the Quaternary-Tertiary volcanic transitional zone has not been specifically reported. Research on the assessment of soil quality widely reported only focuses on the discussion of quantitative-qualitative techniques and the use of minimum data sets without paying serious attention to the soil functions. This study aimed to assess soil quality through qualitative and quantitative methods based on the soil function information approach. The study was conducted in the quaternary-tertiary volcanic transitional zone with special cases of thick soil, high clay content, low nutrient content, high erosion, and vulnerability to landslide, which affects soil quality and farmer cultivation practice. The qualitative soil quality approach was based on the local knowledge of the farmers. The quantitative soil quality indexing was performed with the Soil Management Assessment Framework (SMAF) method to obtain sensitive indicators. The results found that the characteristics of paddy soil had high clay content and thick topsoil layers. The paddy soil is commonly called as ngrawa/mbel soil. The minimum qualitative data sets included color, plant condition, texture, ease of tillage, and drainage. Meanwhile, the minimum quantitative data sets included Na-dd, Mg-dd, texture, bulk density, porosity, and permeability. Information on soil functions obtained included the availability of nutrients, rooting media, root penetration, water storage capacity, and soil permeability. The soil function information approach can be used to assess soil quality in the quaternary-tertiary volcanic transitional zone.
Spatio-Temporal Distribution of Landslides in Java and the Triggering Factors Hadmoko, Danang Sri; Lavigne, Franck; Sartohadi, Junun; Gomez, Christopher; Daryono, D
Forum Geografi Vol 31, No 1 (2017): July 2017
Publisher : Universitas Muhammadiyah Surakarta

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.23917/forgeo.v31i1.3790

Abstract

Java Island, the most populated island of Indonesia, is prone to landslide disasters. Their occurrence and impact have increased mainly as the result of natural factors, aggravated by human imprint. This paper is intended to analyse: (1) the spatio-temporal variation of landslides in Java during short term and long-term periods, and (2) their causative factors such as rainfall, topography, geology, earthquakes, and land-use. The evaluation spatially and temporally of historical landslides and consequences were based on the landslide database covering the period of 1981 – 2007 in the GIS environment. Database showed that landslides distributed unevenly between West Java (67 %), Central Java (29 %) and East Java (4 %). Slope failures were most abundant on the very intensively weathered zone of old volcanic materials on slope angles of 30O – 40O. Rainfall threshold analysis showed that shallow landslides and deep-seated landslides were triggered by rainfall events of 300 – 600 mm and > 600 mm respectively of antecedent rainfall during 30 consecutive days, and many cases showed that the landslides were not always initiated by intense rainfall during the landslide day. Human interference plays an important role in landslide occurrence through land conversion from natural forest to dryland agriculture which was the host of most of landslides in Java. These results and methods can be used as valuable information on the spatio-temporal characteristics of landslides in Java and their relationship with causative factors, thereby providing a sound basis for landslide investigation in more detail.
APLIKASI SISTEM INFORMASI GEOGRAFI DAN PENGINDERAAN JAUH UNTUK ESTIMASI KERUSAKAN PEMUKIMAN AKIBAT BANJIR LAHAR DI KECAMATAN NGLUWAR MAGELANG kumalawati, rosalina; Prasaja, Ahmad Syukron; -, Rijanta; Rijal, Seftiawan Samsu; Sartohadi, Junun; Pradiptyo, Rimawan
Seminar Nasional Aplikasi Teknologi Informasi (SNATI) 2013
Publisher : Jurusan Teknik Informatika, Fakultas Teknologi Industri, Universitas Islam Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar

Abstract

Gunungapi Merapi merupakan salah satu gunungapi paling aktif di dunia. Secara administratif, lereng sisi selatan berada dalam administrasi Kabupaten Sleman, Daerah  Istimewa Yogyakarta, dan sisanya berada pada Provinsi Jawa Tengah, yaitu Kabupaten Magelang di sisi barat, Kabupaten Boyolali di sisi utara dan timur, serta Kabupaten Klaten di sisi tenggara. Beberapa bahaya yang ditimbulkan oleh erupsi Gunungapi Merapi salah satunya bencana banjir lahar yang dapat menyebabkan beberapa kerusakan, diantaranya kerusakan pemukiman. Magelang merupakan salah satu Kabupaten yang terkena dampak bencana banjir lahar dimana salah satunya Kecamatan Ngluwar yang berbatasan dengan Kecamatan Salam dan Tempel di sebelah timur, dengan Kecamatan Muntilan dan Borobudur di sebelah utara, dengan Kecamatan Kalibawang di sebelah barat dan berbatasan dengan Kecamatan Minggir di sebelah selatan. Tujuan dari penelitian ini adalah memanfaatkan aplikasi Sistem Informasi Geografis dan Penginderaan Jauh untuk memetakan estimasi kerusakan pemukiman akibat banjir lahar di Kecamatan Ngluwar dengan menggunakan citra Ikonos dan beberapa peta pendukungnya. Penelitian ini tidak mengangkat aktivitas tanggap bencana, akan tetapi lebih fokus pada teknis pemetaan.Daerah yang tidak rusak jauh lebih luas dibandingkan daerah yang rusak. Hal ini mengindikasikan metode ini cukup berhasil dalam menggambarkan kondisi bencana daerah penelitian. Aplikasi SIG dalam menentukan lokasi risiko ini dapat dilakukan pada sungai-sungai yang berhulu di Gunungapi, guna mengurangi dampak akibat dari bencana banjir lahar di masa yang akan datang. Perlunya pengelolaan secara komprehensif antara pemerintah, masyarakat, dan akademisi dalam hal mengurangi risiko bencana.
Spatial Correlation Between Land Development Level and Vulnerability Level of Mass Movement in the Watershed of Kayangan, Kulon Progo Regency, Yogayakarta Special Region Sartohadi, Junun; Purwaningsih, Rina
Forum Geografi Vol 18, No 1 (2004)
Publisher : Forum Geografi

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Abstract

The objective of this research were: 1) to study the degree of soil development, and 2) to study the spatial correlation between the degree of soil development and the degree of mass movement susceptibility in the research area. The sampling method applied in this research was stratified sampling. Soil mapping units were applied as strata. The sample within strata was determined according the degree of mass movement susceptibility. The degree of soil development was determined using quantitative method of color indices and proflie index. The color indices were Buntley – Westin (B – W), Harden (H), and Hurst. The profile index was determined using solum, texture, structure, and soil consistency. The degree of mass movement susceptibility map was taken from PSBA UGM (2001). Spatial correlation between the soil development map and the mass movement susceptibility map was analyzed using “error matrix”. The result of this research indicated that the degree of soil development in the research area could be classified into three classes, i.e. class 1 (weakly develop soil); class 2 (moderately developed soil), class 3 (strongly developed soil). The degree of mass movement susceptibility was classified into three classes, i.e. class 1 (low susceptibility), class 2 (moderate susceptibility), and class 3 (high susceptibility). The result of error matrix calculation between mass movement susceptibility and soil development were 9.56%; 21.96%; 30.21% for BW + Ha, Hurst, and profile indices respectively. There values showed that there were low spatial correlations between the degree of soil development and mass movement susceptibility in the study area.
Estimation of Soil Moisture Regime Based on Analysis of Rainfall, Air Temperature, and Landform - Soil (Case Study on River Regional Unit (SWS) Pemali - Comal) Sartohadi, Junun; Saragih, Junita
Forum Geografi Vol 18, No 2 (2004)
Publisher : Forum Geografi

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Abstract

The objectives of this research were 1) to determine soil moisture regime based on rainfall and temperature data; 2) to make a correction of the first objective based on soil moisture surplus and deficit calulation; 3) to study the pattern of soil moisture regime distribution in the research area. The field sampling tehniques applied in this research was stratified proposed sampling. Landform unit was applied as strata. Soil depth and texture were considered during field soil sampling within the landform unit. Rainfall and air temperature data were analyzed using Newball Simulation Model (NSM) to determine a tentative soil moisture regime. The tentative soil moisture regime was corrected using calculation soil moisture regime of soil moisture surplus and deficit. The soil moisture surplus and deficit was calculated based on soil depth, soil texture, rainfall, and temperature data. The result of this research were 1) soil moisture regime estimated using NSM ranged from ustic to udic; 2) soil moisture regime corrected using surplus and/ or defiit alulation of soil moisture ranged from xeric to udic; 3) the pattern of soil moisture regime distribution in the reaserch area was not only controlled by the pattern of rainfall – air temperature distribution but it was also controlled by the pattern of soil – landform distribution. Under the some amount of annual rainfall, shallow and coarse texture soils have drier soil moisture regime than deep and fine texture soils.
Evaluasi Pengembangan Wilayah Permukiman Berdasarkan Pemetaan Kerusakan Permukiman Akibat Banjir Lahar Di Kali Putih, Kabupaten Magelang Kumalawati, Rosalina; Rijal, Seftiawan Samsu; Rijanta, R; Sartohadi, Junun; Pradiptyo, Rimawan
TATALOKA Vol 15, No 1 (2013): Volume 15 Number 1, February 2013
Publisher : Universitas Diponegoro

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (491.287 KB) | DOI: 10.14710/tataloka.15.1.13-27

Abstract

The aim of this study are (1) to assess the damage of settlement due to lahar flood in study area, (2) to analyze the damage of settlement and (3) to analyze the allocated space of settlement development based on classification of damage settlement. Methods that used in this study are GPS Tracking to know the distribution of lahar flood, classification of damage settlement based on predetermined criteria and spatial autocorrelation to know the pattern of damage settlement. The result of this study is showing that damage settlement due to lahar flood is not only caused by the house distance to the river but also by the materials of it. The spatial pattern of damage settlement is 0,68 (clustered) for Collapse, 0,62 (clustered) for High Damaged, 1,05(clustered) for Low Damaged, 0,64 (clustered) for Medium Damaged) and 1,21 (clustered) for No Damaged.
SEBUAH DILEMA PERTANIAN ORGANIK TERKAIT EMISI METAN Panjaitan, Ernitha; Indradewa, Didik; Martono, Edhi; Sartohadi, Junun
Jurnal Manusia dan Lingkungan (Journal of People and Environment) Vol 22, No 1 (2015)
Publisher : Pusat Studi Lingkungan Hidup Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (1.84 KB)

Abstract

Gas metana (CH4) adalah salah satu gas rumah kaca yang cukup berperan setelah CO2. Peningkatan metana di atmosfer pada belakangan ini perlu diantisipasi mengingat daya pemanasan global yang ditimbulkannya per satu molekul gas metana di troposfer 21 kali lebih tinggi daripada daya pemanasan satu molekul CO2. Tanah sawah adalah salah satu kontributor gas metana sekitar 10-15%. Metana diproduksi sebagai hasil akhir dari proses dekomposisi mikrobial bahan organik secara anaerobik oleh bakteri metanogen. Emisi gas metana ditentukan oleh pengelolaan air, pengolahan tanah, varietas, dan iklim. Seiring dengan kesadaran masyarakat terhadap produk pangan yang sehat, serta ramah lingkungan, maka permintaan akan beras organik meningkat, sehingga perlu diupayakan dengan giat intensifikasi maupun ekstensifikasi budidaya padi organik. Namun, budidaya padi organik menghadapi dilema yaitu peningkatan produksi gas metana lebih tinggi daripada budidaya padi konvensional.
Geospatial Assessment of Coseismic Landslides in Baturagung Area Saputra, Aditya; Sartohadi, Junun; Hadmoko, Danang Sri; Gomez, Christopher
Forum Geografi Vol 29, No 2 (2015): Forum Geografi
Publisher : Universitas Muhammadiyah Surakarta

Show Abstract | Download Original | Original Source | Check in Google Scholar

Abstract

Java, the most densely populated island in Indonesia, is located on top of the most seismically active areas in Southeast Asia: the Sunda Megathrust. This area is frequently hit by strong earthquake. More than 3,300 M>5earthquakesoccurred between 1973-2014. The wide range of mountainous areas and high intensity of rainfall, make several part of the island one of the most exposed regions for coseismic landslides such as Baturagung area, the Southeast mountainous area of Yogyakarta Province. An integrated method between RS and GIS was used to conduct the vulnerability assessment due to the lack of the site specific slope instability analysis and coseismic landslides data. The seismic zonation of Baturagung area was obtained based on the analysis of Kanai attenuation. The geologic information was extracted using remote sensing interpretation based on the 1:100,000 geologic map of Yogyakarta and geomorphologic map of Baturagung area as well. The coseismic landslide hazard assessment has been estimated using scoring analysis in the GIS platform proposed by Mora and Vahrson (1993) with several modification. The accomplished coseismic landslide hazard map shows medium hazard coverage in the eastern areas, in the upper slope of Baturagung area, which consists of Semilir Formation. The result provides a distinct description of coseismic landslides hazard distribution in Batuaragung area. However, it should only be the preliminary assessment of the site specific investigation especially on valuable area or asset.