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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 | Full PDF (2020.225 KB) | 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. 
Analisi Transisi Lahan di Kabupaten Gunungkidul dengan Citra Penginderaan Jauh Multi Temporal Wardhana, Wahyu; Sartohadi, Junun; Rahayu, Lies; Kurniawan, Andri
Jurnal Ilmu Kehutanan Vol 6, No 2 (2012)
Publisher : Jurnal Ilmu Kehutanan

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (71.575 KB)

Abstract

Gunungkidul was well known as barren area during 1940-1970 but now becomes fully vegetated. This process called the transition process. This study provided empirical evidences by spatial changes and remote sensing analysis and then the results were used for modelling of  the transition phases according to Mather (1992) and Hosunuma (2002). According to the model, the current transition phase is close to the final stage of the growth process. A unique phenomenon of the transition process of re-vegetation is that the regions dominated by settlement/yard, rain fed and upland/fields (in accordance to SNI 7645-2010). This model could be categorize as model of new ecosystem in the transition process, which is different from the previous one. The previous model was in the form of mixed forest as described by Nibbering(1991). This model is a compromise form of socio-ecological aspect as a result of the rehabilitation process, which was conducted by either the public or the Local Government based on Greening  Program of the Central Government according to Presidential Instruction. Interested learning from the process of re-vegetation transition is that the formations of re-vegetation lead to a new ecosystem in Gunungkidul through the dominance of settlement, rain field and upland.IntisariKabupaten Gunungkidul dulu terkenal tandus kering gersang pada tahun 1940-1970-an tetapi kini telah menjadi hijau kembali. Proses ini disebut dengan proses transisi. Penelitian ini memberikan bukti empirik melalui alat bantu analisis perubahan spasial dan penginderaan jauh yang hasilnya kemudian digunakan untuk memodelkan proses tahapan transisi sebagaimana model menurut Mather (1992) dan Hosunuma (2002). Tahapan transisi saat ini menurut model tersebut adalah menuju tahap akhir dari proses pertumbuhan. Yang unik dari proses transisi di wilayah ini adalah model penutupan/penggunaan lahan yang dominan dengan bentuk pemukiman/pekarangan, sawah tadah hujan dan tegalan/ladang (sesuai SNI 7645-2010). Model ini dapat dikatakan merupakan model penyusun ekosistem baru yang terjadi dalam proses transisi yang berbeda dari model penutupan sebelumnya yang berupa hutan campuran sebagaimana dijelaskan oleh Nibbering (1991). Model ini merupakan bentuk kompromi sosial-ekologis hasil proses rehabilitasi saat itu yang dilakukan baik oleh masyarakat maupun oleh Pemerintah Daerah dengan program INPRES Penghijauan dari Pemerintah Pusat saat itu. Pembelajaran yang menarik dari proses transisi adalah kembalinya lahan bervegetasi menjadi sebuah ekosistem baru di Gunungkidul melalui dominasi penutupan/penggunaan lahan pemukiman (pekarangan), sawah tadah hujan dan tegalan/ladang. Bentuk-bentuk ini merupakan proses kompromi yang menjadi faktor keberhasilan rehabilitasi yang dilakukan saat itu.Katakunci: Gunungkidul, transisi hutan, rehabilitasi, perubahan spasial, penginderaan jauh
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 | Full PDF (1736.673 KB) | 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.
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 | 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

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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.
Analisis Transisi Lahan di Kabupaten Gunungkidul dengan Citra Penginderaan Jauh Multi Temporal Wardhana, Wahyu; Sartohadi, Junun; Rahayu, Lies; Kurniawan, Andri
Jurnal Ilmu Kehutanan Vol 6, No 2 (2012)
Publisher : Fakultas Kehutanan Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (71.575 KB) | DOI: 10.22146/jik.5737

Abstract

Kabupaten Gunungkidul dulu terkenal tandus kering gersang pada tahun 1940-1970-an tetapi kini telah menjadi hijau kembali. Proses ini disebut dengan proses transisi. Penelitian ini memberikan bukti empirik melalui alat bantu analisis perubahan spasial dan penginderaan jauh yang hasilnya kemudian digunakan untuk memodelkan proses tahapan transisi sebagaimana model menurut Mather (1992) dan Hosunuma (2002). Tahapan transisi saat ini menurut model tersebut adalah menuju tahap akhir dari proses pertumbuhan. Yang unik dari proses transisi di wilayah ini adalah model penutupan/penggunaan lahan yang dominan dengan bentuk pemukiman/pekarangan, sawah tadah hujan dan tegalan/ladang (sesuai SNI 7645-2010). Model ini dapat dikatakan merupakan model penyusun ekosistem baru yang terjadi dalam proses transisi yang berbeda dari model penutupan sebelumnya yang berupa hutan campuran sebagaimana dijelaskan oleh Nibbering (1991). Model ini merupakan bentuk kompromi sosial-ekologis hasil proses rehabilitasi saat itu yang dilakukan baik oleh masyarakat maupun oleh Pemerintah Daerah dengan program INPRES Penghijauan dari Pemerintah Pusat saat itu. Pembelajaran yang menarik dari proses transisi adalah kembalinya lahan bervegetasi menjadi sebuah ekosistem baru di Gunungkidul melalui dominasi penutupan/penggunaan lahan pemukiman (pekarangan), sawah tadah hujan dan tegalan/ladang. Bentuk-bentuk ini merupakan proses kompromi yang menjadi faktor keberhasilan rehabilitasi yang dilakukan saat itu.Katakunci: Gunungkidul, transisi hutan, rehabilitasi, perubahan spasial, penginderaan jauh Analysis on the Land Transition in Gunungkidul using Multi Temporal Remote SensingAbstractGunungkidul was well known as barren area during 1940-1970 but now becomes fully vegetated. This process called the transition process. This study provided empirical evidences by spatial changes and remote sensing analysis and then the results were used for modelling of  the transition phases according to Mather (1992) and Hosunuma (2002). According to the model, the current transition phase is close to the final stage of the growth process. A unique phenomenon of the transition process of re-vegetation is that the regions dominated by settlement/yard, rain fed and upland/fields (in accordance to SNI 7645-2010). This model could be categorize as model of new ecosystem in the transition process, which is different from the previous one. The previous model was in the form of mixed forest as described by Nibbering(1991). This model is a compromise form of socio-ecological aspect as a result of the rehabilitation process, which was conducted by either the public or the Local Government based on Greening  Program of the Central Government according to Presidential Instruction. Interested learning from the process of re-vegetation transition is that the formations of re-vegetation lead to a new ecosystem in Gunungkidul through the dominance of settlement, rain field and upland.
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 | Full PDF (2020.225 KB)

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. 
A Review of Society’s Behaviour Towards Land Management of Susceptible Area to Landslide in Pekuncen, Banyumas Suwarno, Suwarno; Sartohadi, Junun; Sunarto, Sunarto; Sadharto, Djarot
Forum Geografi Vol 30, No 1 (2016): July 2016
Publisher : Universitas Muhammadiyah Surakarta

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Abstract

Land management is a manifestation of the society’s behaviour in utilizing the land. The objective of the research was to examine the effect of education level, income, land tenure, knowledge, and information input on the society’s behaviour in managing the area susceptible to landslide in Pekuncen sub-district, Banyumas district.   The method of this research was survey by employing questionnaire to collect field data. The variable comprised of the data of education level, income, land tenure, knowledge, and information input.. Stratified random sampling was applied to determine the samples of the research. The area susceptibility class  was considered as the strata in which each stratum consisted of 40 family heads as the respondents. The data analysis applied statistical test of multi-regression. Research area was divided into three classes of landslide susceptibility comprising of low, medium, and high class. Education level, income, land tenure, knowledge, and information input significantly influenced the society’s behaviour dealing with land management (determination co-efficiency (R²) was 69.9 %). It occurred in the area of medium susceptibility class. Information input (regression coefficient/(beta) = 0.817) was the most influential predictor of society’s behaviour in land management located in the low susceptibility class. From this research, it was expected that the description about the factors that influenced the society’s behaviour in managing the landslide-prone area would be a valuable reference in preventing landslide in those areas.