THE EFFECT OF HYDROLOGIC RESPONSE UNIT ON CI RASEA WATERSHED STREAMFLOW BASED ON LANDSAT TM

. This paper discusses spatial pattern of Hydrologic Response Unit (HRU), which is a unit formed of hydrological analysis, including geology and soil type, elevation and slope, and also land cover in 2009. This paper also discusses the impact of HRU on streamflow of Ci Rasea watershed, West Java. Ci Rasea watershed is located at the upstream part of Ci Tarum watersheds in West Java Province, Indonesia. This research used SWAT (Soil and Water Assessment Tool) model to obtain spatial HRU and river flow. The method used Landsat TM data for land cover and daily rainfall for river flow modeling. The results have shown spatial pattern of HRU which was affected by land cover, soil type and slope. In 2009, accumulated surface runoff and streamflow changes were spatially affected by HRU changes. The large amount accumulation of river flow discharge happened in HRU with landcover paddy field, silty clay soil, and flat slope. While the low discharge of river flow happened in HRU with plantation, clay soil, and slightly steep slopes as HRU dominant. It was found that accumulation of surface runoff in Ci Rasea watershed can be reduced by changing the land cover type in some areas with clay and slightly steep slope to become plantation area and the areas with sandy loam soil and flat slope can be used for paddy fields. Beside affected by HRU, the river flow discharge was also affected by the distance of sub watershed to the outlet. By using NS model and statistical t-student for calibration and validation, it was obtained that the accuracy of river flow models with HRU was 70%. It meant that the model could better simulate water flows of the Ci Rasea watershed

SPATIAL PATTERN OF HYDROLOGIC RESPONSE UNIT (HRU) EFFECT ON FLOW DISCHARGE OF CI RASEA WATERSHED USING LANDSAT TM IN 1997 TO 2009

Hydrologic Response Unit (HRU) is a unit formed of hydrological analysis based on geology and soil type, slope, and land cover. This paper discussed the spatial pattern of Hydrologic Response Unit (HRU) in 1997-2009 and its impact on flow Ci Rasea watershed temporally. In this study, SWAT (Soil and Water Assessment Tool) model, based on land cover changed, was used to get HRU and flow in spatially and temporally. This method used Landsat TM 1997, 2003 and 2009 data for land cover and daily rainfall 1997-2009 for flow modeling. The results showed the spatial pattern of HRU in temporally was affected by landcover based on the changing of HRU. The majority of HRU spatial pattern at Ci Rasea watershed were clustered. During 1997-2009, accumulated surface runoff and the changing of flow discharge were affected by changes of HRU spatial pattern. The biggest accumulated surface runoff in Ci Rasea watershed influenced by HRU of agricultural cropland in area of clay soil type with slope slightly obliquely. While the smallest accumulated surface runoff in Ci Rasea watershed influenced by HRU of paddy field in the area of sandy loam soil type with a gentle slope. The changes of HRU agriculture cropland become HRU mixed cropland in area clay soil type with slope at a slight angle and HRU agriculture cropland become HRU paddy field in area, sandy loam soil type with a gentle slope could be decreasing the accumulation of surface runoff in Ci Rasea watershed

ASSESSMENT OF FLASH FLOOD HAZARD POTENTIAL IN A SMALL MOUNTAINOUS CIKUNDUL WATERSHED IN CIANJUR, WEST JAVA, INDONESIA

Flash flood is a geomorphic hazard that can cause huge losses in a short period of time. Cianjur regency, especially Cikundul Watershed is a flash flood frequent area. Therefore, flash flood potential mapping is needed to reduce the threat that can be caused by flash flood. In the flash flood potential mapping, Flash Flood Potential Index (FFPI) method is still rarely applied in Indonesia. This study aims to see the comparison of flash flood potential areas based on models developed in the FFPI method which is Smith, Brewster, Krudzlo, and Ceru models. The four models used slope, land use, soil texture, and vegetation cover as variables. Spatial analysis and statistical test was implemented to validate the flash flood potential areas with flash flood affected locations. The result reveals that Cikundul Watershed was dominated by moderate potential areas based on Brewster, Krudzlo, and Ceru model but low by Smith model. The result also reveals that 65% of 68 Sub-Sub Watershed have different potential and 35% have same potential. High potential areas in all four models was distributed in the Upper Cikundul Watershed. The Crosstab Fit Test result shows that Smith model is the closest model to the actual event

Prioritas Lokasi Revitalisasi Sungai Ciliwung di Wilayah DKI Jakarta: Ciliwung River Revitalization Prioritised Location in DKI Jakarta

Kondisi geomorfologi Jakarta serta bentuk aliran sungai yang bercorak peneplain dibenturkan dengan terjadinya degradasi lingkungan akibat kepadatan penduduk yang terus bertambah menyebabkan kerentanan Jakarta terhadap ancaman bahaya banjir terus meningkat. Dari ke-13 sungai yang mengalir di Jakarta, Sungai Ciliwung menjadi perhatian utama bermula dari sejarahnya sebagai fungsi vital bagi Jakarta sejak jaman Pemerintahan Belanda yang mana merawat Sungai Ciliwung pada saat itu sama dengan menjaga harkat dan martabat Batavia (sekarang Jakarta). Pembelajaran dari negara-negara di Eropa atau Amerika, konsep penanganan sungai yang berhasil dilaksanakan dan menjadi contoh bagi negara lain yaitu menggunakan pendekatan revitalisasi. Revitalisasi sungai berdampak pada peningkatan kualitas lingkungan dan kehidupan yang juga sekaligus menjadi dasar pembangunan berkelanjutan. Urgensi revitalisasi sungai membuat penelitian ini penting untuk dilakukan, yakni membahas kriteria revitalisasi sungai dari perspektif kajian perkotaan untuk mendapatkan tingkat prioritas lokasi revitalisasi. Penelitian menggunakan pendekatan kuantitatif dengan metode Analisis Hirarki Proses (AHP) dan analisis spasial berbasis Sistem Informasi Geografis (SIG). Hasil penelitian menunjukkan bahwa kriteria faktual banjir merupakan kriteria penentu lokasi dengan bobot tertinggi, yaitu 32,4% sehingga setiap segmen pelaksanaan revitalisasi harus memiliki dampak yang besar bagi pengendalian banjir di Jakarta. Adapun lokasi revitalisasi sangat prioritas dimulai dari Jalan TB Simatupang sampai Pintu Air Manggarai

Coastal Physical Vulnerability of Surabaya and Its Surrounding Area to Sea Level Rise

The study for coastal vulnerability to sea level rise was carried out in Surabaya and its surrounding area, it has focused on calculations of the physical vulnerability index were  used coastal vulnerability index (CVI) methods. It was standardized by the multi criteria analysis (MCA) approach according to the study area.  The score of each physical variable derived from remote sensing satellite data and the results of studies that have been done, such as modeling results and thematic maps, and then integrated into geographic information systems (GIS). Result of this study shows that the coastal areas of Gresik, Surabaya, and Sidoarjo in the very low to very high vulnerability level. Physically, the low land areas with open and slightly open coastal have a high vulnerability category. The high level vulnerability was found located in the northern of Madura Strait (Gresik Regency) that overlooks to the Java Sea is about 28.81% from the entire of study areas. Meanwhile, the moderate, low and very low levels of vulnerability were located on Surabaya and Sidoarjo Regency that have more protected coastal area, relatively. According to the physical condition, the coastal elevation is the most variable that contributes to the high of vulnerability index in the coastal of Surabaya City and Sidoarjo Regency.&nbsp

MAPPING BURNT AREAS USING THE SEMI-AUTOMATIC OBJECT-BASED IMAGE ANALYSIS METHOD

Forest and land fires in Indonesia take place almost every year, particularly in the dry season and in Sumatra and Kalimantan. Such fires damage the ecosystem, and lower the quality of life of the community, especially in health, social and economic terms. To establish the location of forest and land fires, it is necessary to identify and analyse burnt areas. Information on these is necessary to determine the environmental damage caused, the impact on the environment, the carbon emissions produced, and the rehabilitation process needed. Identification methods of burnt land was made both visually and digitally by utilising satellite remote sensing data technology. Such data were chosen because they can identify objects quickly and precisely. Landsat 8 image data have many advantages: they can be easily obtained, the archives are long and they are visible to thermal wavelengths. By using a combination of visible, infrared and thermal channels through the semi-automatic object-based image analysis (OBIA) approach, the study aims to identify burnt areas in the geographical area of Indonesia. The research concludes that the semi-automatic OBIA approach based on the red, infrared and thermal spectral bands is a reliable and fast method for identifying burnt areas in regions of Sumatra and Kalimantan

Evaluasi Rencana Tata Ruang Wilayah Berdasarkan Kerawanan Tanah Longsor di Kecamatan Cikakak Kabupaten Sukabumi

Rencana Tata Ruang Wilayah (RTRW) menjadi dasar dalam pengelolaan dan pemanfaatan ruang agar bencana tanah longsor di Indonesia tidak terjadi. Penelitian ini dilatarbelakangi oleh kejadian tanah longsor yang paling sering terjadi di Kecamatan Cikakak setelah tahun 2012 atau saat RTRW telah ditetapkan. Penelitian ini bertujuan untuk memetakan kerawanan longsor dan mengevaluasi rencana tata ruang wilayah di Kecamatan Cikakak terhadap kerawanan longsor. Metode penelitian yang digunakan adalah model Index storie untuk pemetaan kerawanan longsor dan overlay data spasial kerawanan longsor dengan RTRW. Jenis data yang digunakan adalah data kejadian tanah longsor, curah hujan, lereng, litologi, jenis tanah dan penggunaan lahan. Hasil penelitian menunjukkan bahwa Kecamatan Cikakak memiliki kerawanan longsor dominan sedang seluas 7.989,1 hektar (70,9%). Hasil analisis RTRW menunjukkan bahwa rencana tata ruang yang memiliki kerawanan longsor sedang dominan yaitu kawasan hutan konservasi, sedangkan penggunaan lahan permukiman yang telah sesuai dengan RTRW juga memiliki kerawanan longsor tinggi yang luas (249,8 hektar). Sistem peringatan dini, penghijauan, dan pembangunan infrastruktur lainnya di kawasan permukiman dapat dilakukan untuk mengurangi risiko longsor di Kecamatan Cikakak

RISIKO KERUGIAN AKIBAT LONGSOR DI DESA CIBANTENG, KECAMATAN SUKARESMI, KABUPATEN CIANJUR, JAWA BARAT

ABSTRAK Provinsi Jawa Barat merupakan provinsi yang memiliki riwayat kejadian longsor tertinggi di Indonesia. Salah satu wilayah di Provinsi Jawa Barat yang sering terjadi longsor adalah Desa Cibanteng, Kecamatan Sukaresmi, Kabupaten Cianjur. Pada dua tahun terakhir telah terjadi dua kali pergerakan tanah di daerah yang berbeda di Desa Cibanteng. Penelitian ini bertujuan memprediksi besar risiko kerugian bencana longsor pada masa akan datang sehingga bantuan saat terjadi longsor dapat dioptimalkan. Untuk memprediksi besar risiko kerugian digunakan variabel bahaya, kerentanan dan kapasitas kebencanaan longsor. Masing-masing variabel memiliki beberapa indikator tertentu yakni penggunaan tanah, lereng, dan kepadatan penduduk. Penghitungan risiko kerugian dilakukan menggunakan metode overlay masing-masing variabel. Hasil penelitian adalah berupa prediksi risiko kerugian sebesar Rp. 10,1 milyar. Besar risiko kerugian tersebut didapat dari nilai bangunan, jaringan jalan, jaringan listrik dan produktivitas pertanian. Penelitian ini menunjukkan bahwa wilayah risiko bencana longsor mendominasi dibagian selatan Desa Cibanteng.   ABSTRACT West Java Province is a province have a high landslide history in Indonesia. One of the area in West Java Province which often occuring a landslide is Cibanteng Village, Sukaresmi District, Cianjur Regency. In the last two years has been soil movement twice in different areas in the village Cibanteng. This study aims to predict big losses from landslides in future so that assistance can be optimized during a landslide. To predict the risk of loss used hazards variable, vulnerabilities and capacities of landslide disasters. Each variables have some specific indicators namely landuse, slope, and population density. The calculation of losses risk using overlay method in each variable. The results are prediction of losses risk of Rp. 10.1 billion. Great of losses risk can be assessed from value of building , road networks, electricity networks and agricultural productivity. This study shows that risk of landslides dominated in southern of Cibanteng Village

COASTAL PHYSICAL VULNERABILITY OF SURABAYA AND ITS SURROUNDING AREA TO SEA LEVEL RISE

The study for coastal vulnerability to sea level rise was carried out in Surabaya and its surrounding area, it has focused on calculations of the physical vulnerability index were  used coastal vulnerability index (CVI) methods. It was standardized by the multi criteria analysis (MCA) approach according to the study area.  The score of each physical variable derived from remote sensing satellite data and the results of studies that have been done, such as modeling results and thematic maps, and then integrated into geographic information systems (GIS). Result of this study shows that the coastal areas of Gresik, Surabaya, and Sidoarjo in the very low to very high vulnerability level. Physically, the low land areas with open and slightly open coastal have a high vulnerability category. The high level vulnerability was found located in the northern of Madura Strait (Gresik Regency) that overlooks to the Java Sea is about 28.81% from the entire of study areas. Meanwhile, the moderate, low and very low levels of vulnerability were located on Surabaya and Sidoarjo Regency that have more protected coastal area, relatively. According to the physical condition, the coastal elevation is the most variable that contributes to the high of vulnerability index in the coastal of Surabaya City and Sidoarjo Regency. Keywords: coastal vulnerability, sea level rise, remote sensing, CVI, MC

Preferred Site Selection Using GIS and AHP: Case Study in Bangka Island NPP Site

PREFERRED SITE SELECTION USING GIS AND AHP: CASE STUDY IN BANGKA ISLAND NPP SITE. Industrial growth affects the increasing demand for electricity in various places, this also occurs on the island of Bangka. So far, electricity supply has only been obtained from fossil fuel power plants with inadequate capacity, unstable flow and depending on fuel supplies from outside the island. For this reason, it is necessary to build a Nuclear Power Plant (PLTN) which is believed to be reliable and able to overcome these problems. In order to prepare a safe and economical nuclear power plant site, influential parameters such as population density, cooling system, land clearing, cut and fill, and granite for the foundation have been analyzed. The novelty of this analysis lies in 2 methods which gradually used before come up with a final decision, namely spatial analysis and pairwise comparison using Geographic Information Systems (GIS) and Analytical Hierarchy Process (AHP), respectively. The scope of study area is based on the site vicinity (1:5.000) scale, located in the districts of West and South Bangka. The siting process refers to the rules set by the International Atomic Energy Agency (IAEA). Based on the final results of the analysis using the expert choice program, the numerical weights for West Bangka and South Bangka were 0.709 and 0.291, respectively, with a consistency value of 0.03