Identifikasi dan Analisa Kerentanan Banjir Bandang di DAS Cimanuk Hulu Garut dengan Model Shannon's Entropy

Main Article Content

Isabella Hilda Febriyanti
Adam Pamudji Rahardjo
Budi Kamulyan

Abstract

Banjir bandang merupakan salah satu bencana alam dengan karakteristik khusus yang terjadinya secara cepat dan menimbulkan dampak korban jiwa dan kerusakan yang lebih besar daripada banjir biasa. Dari Geoportal Data Bencana Indonesia (BNPB), sepanjang tahun 2009 hingga 2022 tercatat 19 kejadian banjir dan 3 banjir bandang di area DAS Cimanuk Hulu. Penelitian ini bertujuan untuk mengidentifikasi faktor-faktor yang mempengaruhi terjadinya banjir bandang di DAS Cimanuk Hulu serta mengetahui nilai bobot tiap faktor dan indeks kerawanan banjir bandang. Delapan faktor atau parameter yang mempengaruhi banjir bandang di lokasi penelitian digunakan dan dikumpulkan dari berbagai sumber untuk dilakukan perhitungan menggunakan model Shannon’s Entropy sehingga didapatkan nilai Flash Flood Susceptibility Index (FFSI) serta peta kerawanan banjir bandang. Hasil perhitungan menunjukkan bahwa kemiringan lereng, ketinggian, Stream Power Index (SPI) dan curah hujan merupakan empat faktor dengan nilai bobot tertinggi. Nilai FFSI berada pada range 1.296-4.072. Validasi hasil permodelan dengan menggunakan kurva Receiver Operating Characteristic (ROC) menunjukkan hasil sangat bagus (85,8 %).

Article Details

Section
Articles

References

Adi, S. (2013). Karakterisasi Bencana Banjir Bandang di indonesia. Jurnal Sains dan Teknologi Indonesia, 15(2): 42-51.

Arumugam, J., and Anbazhagan, S. (2016). Flood Susceptibility Appraisal in Ponnaiyar River Basin, India using Frequency Ratio (FR) and Shannon’s Entropy (SE) Models. International Journal of Advanced Remote Sensing and GIS, 5(10): 1946-1962. doi:10.23953/cloud.ijarsg.73.

Dhari, I.C.W. (2017). The Use of Rainfall Variability in Flood Countermeasure Planning. Journal of The Civil Engineering Forum, 3(3): 157-165

Fakhrudin, M., dan Daruati, D. (2017). Zonasi Resapan Air Hujan Sebagai Dasar Konservasi Sumber Daya Air DAS Cimanuk. LIMNOTEK Perairan Darat Tropis di Indonesia, 24(1): 26-35.

Haghizadeh, A., Siahkamari, S., Haghiabi A.H., and Rahmati, O. (2017). Forecasting Flood-prone Areas Using Shannon’s Entropy Model. Journal of Earth System Science, 126(3) : 39

Hang, H.T., Hoa, P.D., Tru, V.N., and Phuong, N.V. (2021). Application of Shannon’s Entropy Model and GIS in Flash Flood Forecasting Along National Highway-6, Hoa Binh Province, Vietnam. International Journal of GEOMATE, 21(87) : 50-57.

Kementerian PU dan JICA project. (2012). Petunjuk Tindakan dan Sistem Mitigasi Banjir Bandang. https://www.jica.go.jp/project/indonesian/indonesia/0800040/materials/pdf/outputs_15.pdf

Khosravi, K., Pourghasemi, H.R., Chapi, K., and Bahri, M. (2016). Flash Flood Susceptibility Analysis and Its Mapping Using Different Bivariate Models in Iran: a Comparison Between Shannon’s Entropy, Statistical Index, and Weighting Factor Models. Environmental Monitoring and Assesment, 188(12): 1-21.

Larsen, M.C., Conde, M.T.V. and Clark, R.A. (2001). Landslide Hazards Associated with Flash-Floods, with Examples from the December, 1999 Disaster in Venezuela, Coping with Flash floods. Kluwer Academic Publisher. 259-275p.

Naghibi, S.A., Pourghasemi, H.R., Pourtaghi, Z. S., & Rezaei, A. (2014). Groundwater Qanat Potential Mapping Using Frequency Ratio and Shannon’s Entropy Models in the Moghan Watershed, Iran. Earth Science Informatics, 8(1): 171-186. doi:10.1007/s12145-014-0145-7.

Peta Rupa Bumi Indonesia. (2017)

Pourghasemi, H.R., Mohammady, M., and Pradhan, B. (2012). Landslide Susceptibility Mapping Using Index of Entropy and Conditional Probability Models in GIS: Safarood Basin, Iran. Catena, 97: 71–84.

Pourghasemi, H.R., Pradhan, B., Gokceoglu ,C. ,Mohammadi, M., and Moradi, H.R. (2013a). Application of Weights-of-evidence and Certainty Factor Models and Their Comparison in Landslide Susceptibility Mapping at Haraz Watershed, Iran. Arab Journal Science Engineering, 6: 2351–2365.

Pourghasemi, H.R., Jirandeh, A.G., Pradhan, B., Xu, C., and Gokceoglu, C. (2013b). Landslide Susceptibility Mapping Using Support Vector Machine and GIS at the Golestan Province, Iran. Journal Earth System Science, 122: 349–369.

Pourghasemi, H.R., Moradi, H.R., and Aghda, S.M.F. (2013c). Landslide Susceptibility Mapping by Binary Logistic Regression, Analytical Hierarchy Process, and Statistical Index Models and Assessment of their Performances. National Hazards, 69: 749–779.

Pourghasemi, H.R., Moradi, H.R., and Fatemi Aghda, S.M. (2014). Prioritizing Factors Affecting Landslide and Zonation of Its Susceptibility Using Shannon’s Entropy Index. Soil Water Science, 70: 181–191.

Rahman, A. (2017). Analisis Aliran Pada Daerah Aliran Sungai Cimanuk Hulu (Studi Kasus Cimanuk-Bojongloa Garut). Jurnal Konstruksi, 14(1). https://doi.org/10.33364/konstruksi/v.14-1.391.

Savitri, E., dan Pramono, I.B. (2017). Analisis Banjir Cimanuk Hulu 2016. Jurnal Penelitian Pengelolaan Daerah Aliran Sungai, 1(2): 97-110.

Sulaksana,N., Sukiyah, E., Sjafrudin, A., dan Haryanto, E.T. (2013). Karakteristik Geomorfologi DAS Cimanuk Bagian Hulu dan Implikasinya Terhadap Intensitas Erosi Serta Pendangkalan Waduk Jatigede. Bionatura-Jurnal Ilmu-ilmu Hayati dan Fisik, 15(2): 100-106.

Tejakusuma, I.G. (2016). Bencana Banjir Bandang di Garut 20 September 2016. Jurnal Sains dan Teknologi Mitigasi Bencana, 11(2): 10-18.

Undang-Undang Republik Indonesia Nomor 24 Tahun 2007 tentang Penanggulangan Bencana.

Youssef, A. M., Pradhan, B., and Sefry, S.A. (2016). Flash flood Susceptibility Assessment in Jeddah City (Kingdom of Saudi Arabia) using Bivariate and Multivariate Statistical Models. Environmental Earth Sciences, 75(12). doi:10.1007/s12665-015-4830-8

Yufeng, S., and Fengxiang, J. (2009). Landslide Stability Analysis Based on Generalized Information Entropy. International Conference on Environmental Science and Information Application Technology, 2: 83–85.