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PEMETAAN FAKTOR C YANG DITURUNKAN DARI BERBAGAI INDEKS VEGETASI DATA PENGINDERAAN JAUH SEBAGAI MASUKAN PEMODELAN EROSI DI DAS MERAWU

Jurnal Manusia dan Lingkungan (Journal of People and Environment) Vol 18, No 1 (2011)
Publisher : Pusat Studi Lingkungan Hidup Universitas Gadjah Mada

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Abstract

Penelitian ini bertujuan untuk mengkaji berbagai indeks vegetasi yang diturunkan dari data penginderaan jauh dalam pemetaan faktor C sebagai masukan dalam pemodelan erosi USLE (Universal Soil Loss Equation). Metode yang digunakan dalam penelitian ini adalah dengan menganalisis data penginderaan jauh Landsat 7 ETM + sehingga menghasilkan berbagai indeks vegetasi yang kemudian dilakukan analisis korelasi dengan Faktor C yang diukur di lapangan pada 45 lokasi. Dari analisis ini diperoleh suatu model untuk pemetaan faktor C (C model ) dari berbagai indeks vegetasi. Peta faktor C yang diperoleh kemudian dilakukan validasi pada 48 lokasi sehingga akan diketahui keakuratan hasil pemodelan. Dalam penelitian ini dikaji 11 (sebelas) indeks vegetasi yang diturunkan dari data penginderaan jauh, yaitu ARVI, MSAVI, TVI, VIF, NDVI, TSAVI, SAVI, EVI, RVI, DVI, dan PVI. Hasil penelitian menunjukkan bahwa dari 11 indeks vegetasi yang dikaji terdapat 8 indeks vegetasi yang menghasilkan peta faktor C dengan ketelitian yang tinggi, yaitu MSAVI, TVI, VIF, NDVI, TSAVI, SAVI, EVI, dan RVI. Indeks vegetasi yang menggunakan rumus yang lebih kompleks menghasilkan koefisien korelasi yang lebih tinggi dibanding dengan indeks vegetasi yang menggunakan rumus yang sederhana. Indeks vegetasi yang mempertimbangkan latar belakang tanah (MSAVI dan TSAVI) mempunyai koefisien korelasi lebih tinggi dibanding dengan koefisien korelasi yang tidak mempertimbangkan latar belakang tanah.

Remote sensing techniques for interpretation of landsurface physical variables related to hydrological phenomena in Lembang Area, West Java, Indonesia

Indonesian Journal of Geography Vol 18, No 56 (1988): Indonesian Journal of Geogrphy
Publisher : Faculty of Geography, Universitas Gadjah Mada

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Abstract

The variables related to the hydrological processes within a watershed are considered in four categories: climate, landsurface physical processes, and output variables. Based on the properties of the image of the remotely sensed document, landsurface physical variable is one of these categories which is directly visible on the image, in a broad sense, they may vary from landform to geometrical aspect of channel. On the other hand, features that are not visible on the image, such as, underlying formation, can be deduced from related features that are directly visible.The principal methods of aerial photographic interpretation based on the pattern analysis of the landscape features and the division to the smaller features, are characterized by local pattern elements. The aims of the study are: (i) to get appropriate information about landsurface physical variables through aerial photographic interpretation, (ii) to determine and describe the interrelationship between selected landsurface physical variables and the hydrological processes.The geologic structure of•fault of Lembang area changes the landsurface physical condition, such as, surface drainage pattern, drainage density, landform and local slope, and land use. This fault and the landsurface physical changes appear on the image clearly. The development of the surface drainage is shown quite differently between

Pemanfaatan Citra Penginderaan Jauh dan Sistem Informasi Geografis untuk Pemetaan Daerah Rawan Demam Berdarah Dengue (Studi Kasus di Kecamatan Pangandaran Kabupaten Ciamis Provinsi Jawa Barat)

Aspirator Vol 3, No 2 (2011)
Publisher : Kementerian Kesehatan RI, Badan Litbang Kesehatan, Loka Litbang P2B2 Ciamis

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Abstract

Abstract. Dengue hemorrhagic fever (DHF) are acute febrile diseases, found in tropical and sub tropical regions, caused by dengue virus of the genus Flavivirus, family Flaviviridae. Sub district Pangandaran is an area that is quite a sharp increase in his case. Ranging from no cases in the period 1998-2002 increased 1 case in 2003, 4 cases in 2004, 22 cases in 2005, 35 cases in 2006, 10 cases in 2007, 12 cases in 2008, 14 cases in 2009 and 13 cases in 2010. The purpose of th is study was to determine the ability of remote sensing imagery and G1S in the determination of physical environmental factors for the mapping of areas prone to den­gue fever, dengue fever spreads are based on the distribution of cas es, places, and times from 2005 through to 2010 and determine the level of vulnerability to dengue based on envi­ronmental variables and incidence of DHF. This study is an observational research with cross sectional analysis approach. The results showed that the integration of remote sensing imagery and G1S to analyze the physical environmental risk factors associated with the spread of dengue include: land use, altitude, ra infa ll, area mosquito and fly larvae density area. Distribution pattern of dengue in the district during the last 6 years Pangandaran con­centrated in the southern region of Pangandaran sub-district, the Pangandaran village, Pananjung and Babakan. Distribution of cases based on patient characteristics dominated in the groups of children and adolescents, while based on gender, women are more exposed cases compared to male. 1ncidence of dengue fever occur each after a decline in rainfall from the previous month and decreased at the back there was an increase of ra infa ll. Zoning level of vulnerability to dengue were in the southern district of Pangandaran, the village of Pangandaran, Babakan, Pananjung, Wonoharjo and Most Sukahurip. Broad zone of high vulnerability areas in the Pangandaran sub-district DHF is 22.76 km2 (30.07%), wide area zone vulnerability is 46.16 km2 (60.99%) and broad zones of high vulnerability area 6.75 km2 (8.94%).Keywords: remote sensing image, G1S, dengue risk factor, Pangandaran

TOWARD A FULLY AND ABSOLUTELY RASTER-BASED EROSION MODELING BY USING RS AND GIS

Indonesian Journal of Geography Vol 41, No 2 (2009): Indonesian Journal of Geography
Publisher : Faculty of Geography, Universitas Gadjah Mada

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Abstract

The erosion map data is one of important data used in planningconservation of degraded land. Generally, erosion data is predicted using a modelbecause to gain actual erosion requires much resource (timely, costly and labourintensive). USLE (Universal Soil Loss Equation) is one of existing erosion modelsapplied worlwide, including Indonesia. Nevertheless, erosion analysis conducted isbased on analysis using vector-based maps. This method involves simplification,either algorithms or procedures, and subject to subjectivity, so the result has highuncertainty. This article deals with the idea to build a fully raster-based erosionmodeling. Steps required to obtain raster-based data was highlighted as from thebeginning up to the model validation to get an absolute model. The integration ofremote sensing and GIS was inevitably usedfor the analysis.

PEMANFAATAN CITRA PENGINDERAAN JAUH DAN SISTEM INFORMASI GEOGRAFIS UNTUK PEMETAAN LAHAN KRITIS DI DAERAH KOKAP DAN PENGASIH KABUPATEN KULONPROGO

Jurnal Bumi Indonesia Volume 1, Nomor 2, Tahun 2012
Publisher : Fakultas Geografi UGM

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Abstract

Kerusakan hutan dan lahan dapat terjadi karena faktor manusia maupun bencana alam. Kerusakan lahan yang semakin meluas perlu dilakukan penanganan khusus agar lahan tidak menjadi kritis. Penelitian ini bertujuan untuk: (1) Mengkaji tingkat ketelitian citra ALOS AVNIR-2 untuk memperoleh parameter lahan yang digunakan untuk pemetaan lahan kritis, (2) Menentukan tingkat lahan kritis berdasarkan parameter lahan dari interpretasi citra ALOS AVNIR-2 didasarkan penginderaan jauh dengan bantuan sistem informasi geografis, (3) Pemetaan zonasi tingkat lahan kritis disetiap kawasan di daerah penelitian. Metode yang digunakan yaitu mengacu Departemen Kehutanan SK No. 167/V-SET/2004 dengan cara skoring bobot tertimbang. Parameter yang digunakan yaitu penutup lahan, kemiringan lereng, tingkat bahaya erosi, produktivitas, manajemen lahan, dan prosentase batuan. Hasil pemetaan tingkat lahan kritis di daerah Kokap dan Pengasih diperoleh tingkat lahan tidak kritis dan potensial kritis dengan luas 1948,81 ha dan 323,1 ha, agak kritis 8507,71 ha, kritis 1924,86 ha dan sangat kritis 211,51 ha.Kata kunci : Penginderaan jauh, SIG, lahan kritis, citra ALOS AVNIR-2 

Aplikasi Penginderaan Jauh Dan Sistem Informasi Geografis Untuk Mengkaji Perubahan Koefisien Limpasan Permukaan Akibat Letusan Gunung Merapi Tahun 2010 Di Sub Das Gendol Yogyakarta

Jurnal Bumi Indonesia Volume 2, Nomor 1, Tahun 2013
Publisher : Fakultas Geografi UGM

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Perubahan fisik lahan yang terjadi pada sub DAS Gendol disebabkan oleh terjadinya erupsi Gunung Merapi pada tahun 2010 akan mempengaruhi koefisien limpasan permukaan. Penelitian ini bertujuan untuk mengkaji perubahan fisik lahan dan pengaruhnya terhadap nilai koefisien limpasan permukaan dan mengetahui perubahan koefisien limpasan permukaan pada Sub DAS Gendol sebelum dan sesudah letusan Gunung Merapi tahun 2010. Metode yang digunakan untuk memperoleh nilai koefisien limpasan dalam penelitian ini adalah Metode Cook dengan mempertimbangkan faktor penutup vegetasi, kemiringan lereng, timbunan air permukaan dan infiltrasi tanah sebagai parameternya. Hasil perhitungan menunjukkan bahwa nilai koefisien limpasan pada tahun 2008 yaitu 65% dan berubah menjadi 67% setelah letusan tahun 2010. Hasil analisis menunjukkan bahwa perubahan parameter fisik lahan yang paling berpengaruh terhadap perubahan nilai koefisien limpasan adalah infiltrasi tanah dan penutup vegetasi.Kata kunci: koefisien limpasan permukaan, metode Cook, perubahan fisik lahan

PENGEMBANGAN METODE BANGKITAN DAN TARIKAN PERJALANAN BERDASARKAN CITRA QUICKBIRD

Jurnal Transportasi Vol 13, No 2 (2013)
Publisher : Jurnal Transportasi

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Abstract

As a basic model, trip generation model aims to obtain the number of movement generated by each origin and the one attracted to each destination zone. Based on the movement, trip generation model is categorized into home-based trip generation and non home-originated/destinated trip attraction. Given that the different types of activities attract trips with different characteristics, it can be concluded that land use management determines the movement and activities. Remote sensing imagery has been extensively used in various research themes including land use management or land use and detailed land utility. As one of the remote sensing imageries, Quickbird imagery is advantageous with its high spatial resolution which is 0.61 cm. Therefore, it is interesting to apply the 0.61 cm spatial resolution to the trip generation model to estimate the number of trips at the trip generation. This aims is to minimize field activities which are high cost, extensive workers, and relatively time consuming.Keywords: trip generation model, trip attraction, quickbird imagery

Underground Leachate Distribution Based on Electrical Resistivity in Piyungan Landfill, Bantul

Indonesian Journal of Geography 2018: ARTICLE IN PRESS
Publisher : Faculty of Geography, Universitas Gadjah Mada

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Abstract

Piyungan Landfill is constructed to accommodate the disposal of wastes from Yogyakarta City, Sleman Regency, and Bantul Regency. Overland flow that passes through landfillsand potentially dissolves organic and anorganic materials in a high concentration is referred to as leachate. Leachate is easily transported by overland flow. It can seep through soil or land surface and, then, infiltrate into groundwater, which is commonly accessed through residential wells. Therefore, a study on leachate distribution pattern from landfill to the surrounding area becomes necessary particularly due to the potential of leachate to contaminate the environment via groundwater whose characters are latent and difficult to monitor. This research aims to (1) identify areas that experience groundwater pollution caused by leachate movement, (2) identify the distribution of electrical resistivity in polluted areas as well as the spread direction of leachateto the surrounding area, and (3) to develop a leachate management model. This research uses Electrical Resistivity Tomography (ERT) survey in order to identify the distribution of electrical resistivity in polluted areas. Groundwater quality analysis is used for validating the interpretation of ERT survey. The spread direction of leachate is identified from stratigraphic Fance model correlated with geologic and hydrologic data. The results show that groundwater contamination has occurred in the research area, as indicated by very low electrical resistivity in aquifer zone, i.e. 3-9 Ωm. Such low electrical resistivity is caused byincreased ions in groundwater as the results of leachate migrating downward into groundwater. The increased ions will trigger an increase in electrical conductivity (EC), i.e. up to 1,284 μmhos/cm, and a decline in electrical resistivity. The leachate spreads westward and northward at a depth of 6-17 m (aquifer) with a thickness of pollution between 4-11 m. The recommended landfill management model, emphasizing on leachate movement, include base lining (liner), leachate collection channel, geomembrane cap, and leachate treatment.

PROPOSED MODEL ON LEVELS OF DEGRADED LAND AT MERAWU WATERSHED, BANJARNEGARA REGENCY, CENTRAL JAVA PROVINCE, INDONESIA

BIOTROPIA - The Southeast Asian Journal of Tropical Biology Vol 24, No 3 (2017)
Publisher : SEAMEO BIOTROP

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Abstract

Conservation of degraded land in Indonesia requires maps of degraded land. The maps were established based on a model developed in 1998 by the then Indonesia Department of Forestry. The model has 2 weaknesses i.e. 1. high level of uncertainty due to vector-based data used to build the thematic maps and 2. parameters redundancy or duplication from the model. This research was aimed to build up a proposed model on levels of degraded land at Merawu Watershed using fully raster-based data supported with remote sensing and GIS techniques. Parameters analyzed were Slope, Erosivity (R), Erodibility (K), Slope Length and Steepness (LS), Cover and Management (C), Support Practice (P) and Percentage of Canopy Cover. These data were presented in fully raster format. Management parameter was not explicitly used in this research because management parameter was already represented by the C and P parameters . Five parameters were directly obtained using fully raster format, i.e. Slope, LS, C, P and Percentage of Canopy Cover. The other 2 parameters went through spatial interpolation process before being presented as fully raster format. Correlation analysis among parameters was carried out. Parameters having high correlation coefficient (r ≥ 0.8) were excluded from the model to avoid redundancy. The proposed model only used parameters having low correlation coefficient. The research result showed that the determination of levels of degraded land was more accurate when using only erosion parameters, formulated as:Level of Degraded Land (LoDL) ≈ Erosion ≈ R x K x LS x C x P. 

Utilization of Remote Sensing Techniques for Monitoring and Evaluation of Solo Watershed Management

Forum Geografi Vol 17, No 2 (2003)
Publisher : Forum Geografi

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Abstract

This research is an application of remote sensing technology for monitoring and evaluation of watershed management, which was conducted is Solo Watershed, Central and East Java. The research objectives were 1) to investigate the capability of photomorphic analysis of Landsat Thematic Mapper (TM) and Enhanced Themmatic Mapper (ETM +) imagery as the basic for analyzes of landforms, landuse, and morphometry of the land surface; 2) to calculate the overland flow – peak discharge and erosion – sediment yield as indicators of land degradation of the area; 3) to use the indicators as set of instrument for monitoring and evaluation of watershed management. In this study, visual interpretation by means of on-screen digilization of the digital imagery was carried out in order to identify and to delineate land parameters using photomorphic approach. Based on the photomorphic analysis, several image – based parameters such as relief topography, physical soil characteristic, litho – stratigraphy, and vegetation cover were integrated with other themati maps in a geographic information system (GIS) environment. Estimation of overland flow (C) based on Cook methods (1942) and calculation of peak disccharge (Qmax) based on rational method (Qmax = C. I. A) were applied. Meanwhile, estimation of surface erosion was carried out using Universal Soil Loss Equation (USLE, A = R. K. L. S. CP). The sediment yield (Sy) was estimated using seddiment delivery ratio ( SDR) based on the following formula: Sy = [A + (25% x A)] x SDR. Both pairs of C – Qmax and A – Sy, were utilized as the basis for monitoring and evaluation of the watershed. The combination of C – Qmax and A – Sy were also used as the basis for selection of stream gauge setting / AWLR within particular sub – catchment. It was found that the photomorphic analysis is only color/tone, slope aspects, pattern, and texture, unit boundaries between volcanic – origin landscape (Wilis volcanic complex) and folded – hills landforms (Kendeng ridges) can be delineated. Within the volcanic features, coarse – textured units indicating pyroclastic materials with high drainage density (western part of Lawu volcano). In terms of calculated overland flow and peak discharge of 100 sub – catchment within the Solo Watershed, it was found that there are four sub – catchment with relatively high values (> 0.60 and > 1200 m3s1 for overland flow and peak discharge repectively), namely Samin (Karanganyar), Keduang (Wonogiri), Dengkeng (Klaten), and Sungkur (Ponorogo). Five sub-catchment might be categorized as having moderate peak discharge (Qmax ranges from 1000 – 1200 m3s1), namely Ketonggo (Ngawi), Keyang (Ponorogo), Gandong – Semawur (Magetan), Pepe (Boyolali), and Soko (Bojonegoro), while the remaining 91 sub-catchments are categorized as having low peak discharge. Based on the calculation of erosion and sediment yield, there was no sub-catchment with moderate category (60 – 180 ton ha1yr1), i.e. Samin (Karanganyar), Gonggong (Magetan), Ngisip and Kedung Cilik (Tuban), and Pepe (Boyolali). The other 95 sub-catchment might be categorized as gentle to good. In terms of values representing overland flow – flood and erosion – sediment yield, there are several sub-catchments require first priority in monitoring and evaluation, and are recommended as suitable sites for stream gauge setting, i.e. Samin (Karanganyar), Gonggong (Magetan), Ngisip and Kedung Cilik (Tuban).