ISBN : 978-979-8452-45-1 PROCEEDING INAFOR 2011 International Conference of Indonesia Foreesstry Researchers “Strengtheninng Forest Science and Technology foor Better Foorestry Development” Bogor, 5-7 Desember 2011 EDITORS : Dr. IBB. Putera Parthama Dr. Achmad Fauzi Mas’ud Dr. Nina Mindawati Prof. Dr. Gustan Pari Dr. Haruni Krisnawati Dr. Krisdianto Dr. Atok Subiakto Ir. Retno Maryani, M.Sc Dr. Titiek Setyawati Dr. Budi Leksono Dr. Maman Turjr aman Dr. Efi Yuliaty Yovy Dr. Leti Sundawati Dr. Dodik Ridho Nurrochmat Proof Reader : Dr. IBB. Putera Parthama Dr. Dede Rohadi Ministry of Forestry Forestry Research and Development Agency 2012 INAFOR11P-009 Genetic Diversity of Four Populations of Arenga pinnata MERR Revealed by Isozyme Markers (Liliek Haryjanto, Prastyono and Burhan Ismail) ............................................................................... 765 INAFOR11P-010 Log Tracking of Merbau (Intsia bijuga) using DNA Markers: Strategy and Research Status (Anto Rimbawanto and AYPBC Widyatmoko) .................................................................................. 771 INAFOR11P-011 The Influence of Growth Medium and Shading to the Growth of Seven Month’s Old of Manglid (Manglietia glauca BL) Seedlings (Rina Bogidarmanti, Rina Kurniaty and Ratna Uli Damayanti) .......................................................................................................... 778 INAFOR11P-012 Microhydro: Green Energy from Forest Area Enhancing Better Relationship Between Forest and People (Hunggul Yudono) ........ 788 INAFOR11P-013 Wood Stump: Harvesting Technique and Chemical Properties (Sukadaryati and Dian Anggraini Indrawan) ................................ 794 INAFOR11P-014 Agroforestry Forest Estate: Whole Rotation of Social Forestry (Triyono Puspitojati) ....................................................................... 804 INAFOR11P-015 The Use of Natural Dye Plants in East Nusa Tenggara (Siswadi, Dani S. Hadi and Soenarno) ............................................................ 812 INAFOR11P-016 The Traditional Use of Woka Palm (Livistona rotundifolia Mart.) as Non-Timber Forest Product in North Sulawesi (Diah Irawati Dwi Arini)............................................................................................... 822 INAFOR11P-017 Assessing FTA Cards for DNA Capture from Different Types of Fungal Material (Purnamila Sulistyawati) ....................................... 830 INAFOR11P-018 Pest and Disease Attack on Nyamplung (Calophyllum inophyllum) Seedling in the Nursery (Eritrina Windyarini and Burhan Ismail) ... 841 INAFOR11P-019 Growth and Proliferation of Embryogenic Callus of Sandalwood (Santalum album L.) (Yoni Herawan) ........................ 848 INAFOR11P-020 Identification for Some Rattan Species on Region Ingkwosi Forest Area Manokwari District (Titi Kalima and Jasni)............. 855 INAFOR11P-021 Puccinia meibomiae (Uredinales) of Erythrina crista-galli in Indonesia (Dono Wahyuno) ............................................................................ 863 INAFOR11P-022 Optimation of Somatic Embryos Formation of Shorea pinanga Scheff. Through Suspension Culture (Yelnititis)............................. 869 INAFOR11P-023 Landslide Hazard Mapping to Support the Handling of Landslide Hazard in the Upstream Deli Watershed (Rahmawaty, Bejo Slamet, Abdul Rauf and Anita Naomi) .......................................... 876 INAFOR11P-024 Study of Traditional Agroforestry System in West Nusa Tenggara: Finding the Alternative of DA REDD Site Based on Carbon Stock (Ryke Nandini)........................................................................ 882 INAFOR11P-025 Four Types of New Record for Diospyros in Tangkoko Nature Reserve in North Sulawesi (Julianus Kinho).................... 888 ix Jl. Tri Dharma Ujung No. 1, Kampus USU, Medan, North Sumatra, 20155, INDONESIA Poster paper prepared for The First International Conference of Indonesian Forestry Researchers (INAFOR) Bogor, 5 – 7 December 2011 INAFOR SECRETARIAT Sub Division of Dissemination, Publication and Library FORESTRY RESEARCH AND DEVELOPMENT AGENCY Jl. Gunung Batu 5, Bogor 16610 Landslide Hazard Mapping to Support the Handling of Landslide Hazard in the Upstream Deli Watershed Rahmawaty1, Bejo Slamet1, Abdul Rauf2 and Anita Naomi1 1Department of Forestry, Faculty of Agriculture, Sumatera Utara University, Jl. Tri Dharma Ujung No. 1, Kampus USU, Medan, North Sumatra, 20155, INDONESIA Corresponding email: [email protected] 2Department of Soil Science, Faculty of Agriculture, Sumatera Utara University, Jl. Tri Dharma Ujung No. 1, Kampus USU, Medan, North Sumatra, 20155, INDONESIA ABSTRACT Natural disasters landslides as one natural phenomenon is one of the environmental problems that often occur in the province of North Sumatra, Indonesia. Landslides usually occur in the watershed upstream. The upstream of Deli Watershed is located in Karo Regency. Karo Regency is an area that has the potential for landslides; this region is mostly located in the highlands. This research aimed to identifying and mapping of landslide prone areas in Karo Regency and provided advice to the government in an effort to support the handling of dangerous landslides. This research used data such as: earth feature of Indonesia map/Peta Rupa Bumi Indonesia (RBI) or what is called as basic map with scale 1:50000, slope map, geological map and land cover/land use map. Processing was done with overlaid each parameter to determine landslide hazard using Geographic Information System. The results showed that in the upstream region DAS Deli, landslide hazard was dominated by high-class, followed by a very 872 high grade, medium, low and very low. The Class which very high landslide hazard contained in the Sub-district of Tiga Binanga, there was a high grade in the Sub-district Mardinding, while other classes (medium, low and very low) spread over several districts in Karo Regency. The main causes of landslides in this area mainly due to the slope factor, type of rock, soil, and land use. Keywords: Landslide, mapping, Deli watershed, environmental, Karo Regency 1. INTRODUCTION 1.1 Background Landslides usually occur in the watershed upstream. Natural disasters landslides as one natural phenomenon are also one of the environmental problems that often occur in the province of North Sumatra, Indonesia. The upstream watershed Deli is located in Karo Regency. Karo Regency is an area that has the potential for landslides; this region is mostly located in the highlands. Many factors can affect the stability of slopes that lead to the occurrence of landslides. These factors include: geological and hydrological conditions, topography, climate and weather changes. According to Priyono et al. (2006), the potential for soil erosion can be minimized by empowering communities to identify typologies of landslide prone slope lands, the early symptoms of the slope will move, and efforts should be done early anticipation. Effective early warning system should be made based on predictions, when and where landslides will occur also actions that should be done when disaster strikes. Geographic information systems can be used in determining the priority areas for disaster relief. According to Burrough (1986), a geographic information system (GIS) is a powerful set of tools for collecting, storing, retrieving, transforming and displaying spatial data from the real world for a particular set of purpose. GIS technology integrates common database operations such as query and statistical analysis with the unique visualization and geographic analysis benefits offered by maps (ESRI, 2007). An area most vulnerable to disasters is a main priority in conducting mitigation measures. By this research, it is known that areas prone to landslides, so early prevention can be done. If the anticipation is not immediately done, losses due to landslides would not be inevitable. 1.2 Objective This study generally aimed to identifying and mapping of landslide prone areas in Karo Regency and provided advice to the government in an effort to support the handling of dangerous landslides. 2. MATERIAL AND METHODS 2.1 Description of the Study Area The research was conducted in Karo Regency (the upstream of Deli Watershed). Geographically, it is located between 2050’ - 3019’ LU dan 97055’ - 98038” BT (Figure 1). This research was conducted during January to July 2010. Data analysis and processing were performed at the Laboratory of Integrated Forest Management, Department of Forestry, University of Sumatera Utara. 873 Figure 1: Map of study area 2.2 Data Collection This research used data such as: earth feature of Indonesia map/Peta Rupa Bumi Indonesia (RBI) or what is called as basic map with scale 1:50.000, slope map, geological map and land cover/land use map. Processing was done with overlaid each parameter to determine landslide hazard using Geographic Information System. 3. RESULT AND DISCUSSION Based on the district in Karo Regency, the distribution of landslide prone consists of five classes, namely: very low, low, medium, high, and very high. Distribution of landslide hazard based on the district was not evenly distributed in each sub-district as is presented in Figure 2. (based on analysis on the map and checking in the field). Each class of landslide hazards was marked with different colors. Landslide Very low Low Medium High Very high Figure 2: Map of landslide hazard class in Karo Regency 874 Source: Analysis result (2010) Characteristics of landslides are most commonly found