Supiturang is one of the villages in Kecamatan Pronojiwo, Kabupaten Lumajang that sits on the lahar flow path of Semeru Volcano. The village constantly faces a lahar-flood hazard, inevitably impacting the local community. Therefore, this paper aims to map the lahar-flood hazard of Supiturang village using the analytical hierarchy process (AHP) method. The main parameters are 1) slope (%), 2) distance from drainage (m), 3) elevation (m ASL), 4) rainfall (mm), and 5) land cover (water body/bare land/forest/grassland/plantation/ricefield/mixed agriculture/built-up area). This research is a descriptive-quantitative study that used survey and geographic information system (GIS) approaches. The result showed that the lahar-flood hazard class of Supiturang varies from very low, low, moderate, high, to very high. The very high hazard class is distributed near the lahar flow path. Despite most settlements being in the moderate hazard class, some are in the high and very high hazard class. The findings from this research can advantage the further improvement and development of evacuation routes, assembly points, refuges, observatory stations, and other related Semeru Volcano disaster risk mitigation actions.

Geomorphology affects the potential of land. The geomorphological condition of an area has implications for physical characteristics, including: 1) type; 2) material; and 3) processes formed upon it. Understanding land capability allows for the evaluation of land suitability. Classification of land suitability is carried out by combining the results of land capability identification with requirements for plant growth or existing land use. Evaluation of land suitability can be done using the survey method. This study aimed to assess the suitability of land in Sumbersuko Village in Wagir District, Malang Regency. Land suitability was evaluated by matching the characteristics of the land with the land suitability class. This study used primary data taken from the regional morphology survey. Secondary data included: 1) digital elevation model data; 2) geological maps; 3) maps of soil types; and 4) Sentinel-2A images. The data from the field survey were then compiled using a geographic information system into maps using 2D and 3D modeling. The results of GIS analysis showed that Sumbersuko Village has six landform units, namely M1V1, M1V2, H2V2, U2V2, P2V2, and M3V3. Analysis of land capability and suitability of the six land units in a row gave the following results: 1) forest (highly suitable/S1); 2) forest and industry (suitable/S2); 3) plantation/agrotourism (moderately suitable /S3); 4) agriculture (not suitable/N); 5) residential area (less suitable/S3) S4); and 6) forest (highly suitable/S1). Keywords: scientific, approach, methodological, techniques, geography

Sampang Regency is susceptible to flood which caused by river overflow due to rainfall peak period and rising seawater. Kamoning watershed is one of an area that got annual overflow flood. While the coastal area of Sampang Regency faces rising-seawater flood/high-tide flooding. This research aimed to map the flood susceptibility class in Sampang Regency using a morphological approach. Remote sensing and GIS analysis was used to classify the area into three flood susceptibility classes: high, moderate, and low. After that, the map is verified using hydrostratigraphy analysis using the geoelectric Schlumberger method. Based on the identification, 6 villages in 9 subdistricts located alongside the Kamoning River have a high flood susceptibility owing to river overflow. On the other hand, rising seawater is causing floods in Sreseh Sub-District, Jrengik Sub-District, Pangarengan Sub-District, Sampang Sub-District and Camplong Sub-District in the southern part of Sampang Regency, whereas Banyuates Sub-District, Ketapang Sub-District and Sokobanah Sub-District in the northern part. Consequently, those areas are also classified as high flood susceptibility areas. The hydrostratigraphy analysis showed that the surface of Sampang Regency is mainly composed of clay. With low permeability level (0.0002 m/day), water pools and surface runoff could easily be generated when rain falls.