Identification of groundwater potential through the characteristics of the aquifer layer is an important study. This is useful for knowing the availability of shallow groundwater in an area. Arjosari Village, Kalipare District, Malang Regency is an area that often experiences shortages in meeting daily water needs, especially during the dry season. The availability of groundwater at the research site is influenced by the area's topographical conditions, which range from flat to very steep.This study aims to identify the location of the aquifer and groundwater potential in Arjosari Village. This study uses the Schlumberger configuration to identify aquifers and groundwater. This method adheres to the basic principle that each rock layer has a different resistivity value. In addition to rock material type factors, the level of saturation and chemical composition in water affects the value of resistivity. The results showed that the aquifer characteristics and groundwater potential were different for each lithological condition, slope, soil type, and land use. In the research location, shallow aquifers were found less than 20 meters while there were also deep aquifers located more than 25 meters below the ground surface. Shallow aquifers can be used as a water source by the community, especially to meet their daily water needs. The results of this study are used for Geography learning on hydrological material.

Abstrak: Sub DAS Amprong secara administrasi masuk pada wilayah Kabupaten Malang dan Kota Malang. Meliputi lima Kecamatan yakni: Kedungkandang, Poncokusumo, Tumpang, Pakis dan Jabung. Risiko bencana longsor tergolong tinggi pada kawasan ini. Maka dari itu, penelitian ini bertujuan untuk melakukan pengurangan risiko bencana longsor mengunakan pendeketaan GIS (Geographic Information System). Menggunakan GIS distribusi tingkat risiko akan dapat diketahui dengan baik, sehingga mampu memberikan solusi yang lebih akurat. Penelitian ini meliputi empat tahapan: 1) pemetaan bahaya longsor, 2) pemetaan kerentanan bencana, 3) pemetaan kapasitas bencana, 4) pemetaan risiko bencana. Hasilnya diketahui bahwa kecamatan Jabung dan Poncokusumo merupakan wialayah dengan tingkat risiko longsor paling tinggi. Upaya yang dapat dilakukan untuk mengurangi tingkat risiko dapat dilakukan melalui mitigasi bencana secara struktural dan nonstruktural. Wilayah dengan risiko tinggi bukan merupakan kawasan pemukiman, namun memiliki aktivitas utama berupa pertanian. Oleh karena itu perlu adanya manajemen risiko bencana longsor dalam usaha longsor seperti: dengan cara: 1) pengaturan sistem irigasi dengan baik, 2) penerapan sistem terasering, dan 3) pemasangan bronjong pada kaki lereng. Abstract: Amprong watershed is administratively included in Malang Regency and Malang City. Includes five districts namely: Kedungkandang, Poncokusumo, Tumpang, Pakis and Jabung. The risk of landslides is classified high in this region. Therefore, this research aims to reduce the risk of landslides using GIS (Geographic Information System). Using GIS the distribution of risk levels will be well known, so as to provide a more accurate solution. This research includes four stages: 1) mapping of landslide hazards, 2) mapping of disaster vulnerability, 3) mapping of disaster capacity, 4) mapping of disaster risk. The results are known that the Jabung and Poncokusumo sub-districts are areas with the highest risk of landslides. Efforts that can be made to reduce the level of risk can be done through structural and nonstructural disaster mitigation. High risk areas are not residential areas, but have major activities in the form of agriculture. Therefore, it is necessary to have landslide risk management, such as: by: 1) regulating the irrigation system properly, 2) applying the terracing system, and 3) installing gabions at the foot of the slope.

The study of landslides for long time is studied by geomorphological approach. In the study of geomorphology, each and every spatial segment of the earth surface possesses some physiographic aspects. Its analysis enables us to predict an interrelationship between physical and cultural phenomena as a whole. Pacet is one of the most susceptible areas due to landslides in Mojokerto Regency, East Java. Pacet is located at mountainous area which the slope stability depends upon physical and chemical properties of the soil. Such condition is represented on the geomorphic properties, such as slope angle, slope aspect, profile curvature, TWI, TPI, SPI and lithological composition. To obtain a proper landslides susceptibility mapping, some data were derived from geospatial data such as slope angle, slope aspect, profile curvature, TWI, TPI and SPI. DEM extraction by GIS platform were used to obtain the data. Soil samples were collected from different landform unit. The spatial distribution of landslides data was processed using GIS Software. The result shows that landslides were influenced by slope, aspect, profile curvature, TWI, TPI, SPI and lithological composition in study area.

Banjir Bandang merupakan salah satu ancaman bencana di Kecamatan Dau, Kabupaten Malang. Tercatat kejadian bencana banjir bandang terjadi di tahun 2002, 2012 dan 2020. Tahun 2002 kejadian banjir bandang mengakibatkan satu orang korban meninggal dunia dan mengakibatkan 67 rumah rusak. Sebagai upaya mitigasi bencana, penelitian ini melakukan pemetaan tingkat kerawanan banjir bandang di Kecamatan Dau, Kabupaten Malang. Pemetaan tingkat kerawanan banjir bandang dalam penelitian ini menggunakan metode AHP (Analytic Hierarvhy Process). Terdapat empat tahapan dalam proses penelitian ini, yaitu: 1) analisis parameter kriteria, 2) analisis AHP, 3) reclassify data raster, dan 4) kalkulasi data raster. Hasil penilai tingkat kerawanan banjir bandang di bagi menjadi lima kelas, yaitu: sangat rendah, rendah, sedang, tinggi, sangat tinggi. Secara umum Kacamatan Dau memiliki tingkat baya banjir bandang dengan kelas rendah hingga sedang. Umumnya Kacamatan Dau memiliki tingkat kerawanan banjir bandang dengan kelas rendah hingga sedang. Tingkat kerawanan banjir bandang sangat tinggi terdapat pada Desa Kucur. Sementara itu, tingkat kerawanan sangat rendah ada pada Desa Mulyoagung dan Landungsari. Distribusi tangkat kerawanan tinggi berada pada jarak 10—25 dari saluran drainase atau sungai. Sementara kelas sangat tinggi berada pada jarak 0—10 dari saluran drainase atau sungai.

Kecamatan Pacet, Kabupaten Mojokerto is one of an area with many landslide events in East Java Province. As a mitigation effort, this research aimed to map the landslide susceptibility class distribution of the research area. This research applied a machine learning analysis technic which combined Frequency Ratio (FR) and Logistic Regression (LR) models to assess the landslide susceptibility class distribution. FR bivariate analysis is used to normalized the data and to identify the influence significancy on each class of triggering factors. LR multivariate analysis is applied to generate the landslide probability (susceptibility) and to show the influence significancy of each triggering factor to landslide events. There are 12 triggering factors to landslide used in this research, which is: TPI, TWI, SPI, slope, aspect, elevation, profile curvature, distance to drainage, geological unit, rainfall, land use, and distance to the road. This research has 383 landslides and 383 non-landslide events as the data sample based on field survey, BPBD Kabupaten Mojokerto, and Google Earth Pro imagery interpretation. The proportion of dataset training and testing is 70% and 30%, which generated from the data inventory. This research used ROC analysis to validate the landslide susceptibility model. The result showed that the landslide susceptibility model has an AUC value of 0.91, which indicated that the model has high accuracy.