The Brantas Watershed located in East Java has the vulnerability of drought as one of hydrometeorological disasters. The Vegetation Health Index (VHI) as one of remote sensing index was used to analyse drought. VHI can be derived based on both the Land Temperature Surface (LST) and Normalized Differenced Vegetation Index (NDVI). This research aimed to determine the influence of LST and NDVI, respectively, to VHI, especially in dry season of 2008 - 2017. The data used were MODIS Vegetation Indices (MOD13A1) and MODIS Land Surface Temperature (MOD11B1). The influence of LST and NDVI to VHI in the Brantas Watershed was analysed using correlation and regression testing. The LST - NDVI correlation of Brantas Watershed was negative (-0.73). The high temperature distribution was dominantly located in the low-density vegetation areas. The LST - VHI correlation was 0.35, and NDVI - VHI correlation was 0.63. This illustrated that the influence of land surface temperature to the vegetation drought was weak. Drought indicated by VHI was more likely to be influenced by internal conditions of vegetation and other environmental elements.

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Sumberpitu water springs was the one of primary resources, not only for people living in around of Bromo Mountain, but also for people living in Malang City. The water spring was very important for them to sustain their life activities. The importance of that urged people to be aware how important conservation activities was. Understanding conservation activities was done using System Dynamics approach which was part of system thinking helping to be understand real life condition. Causal Loop Diagram (CLD) is a system dynamics form having feedback among the variables. Water-Human-Land System (WHLS) Sumberpitu water spring Conservation was used as CLD Model. The CLD Model used Groundwater Storage including Sumberpitu water spring, Built-Up/Opened Area and Agricultural Areas in the Upper stream of water springs, and Rural and Urban Population as primary variable. The variables have both influence and feedback to each other. Conservation activities were done by local people including water prices variable as environment services charge, conservation education variable, and Adat Karo traditional ceremony as a local wisdom. For sustaining Sumberpitu water spring use, the conservation activities were expected to control, not only water use, but also land use change in the upper stream of water springs.

This study aims to obtain an overview of hydrogeomorphological conditions in Zero Order Basin in Brau Village. Quantitative approaches are used by using primary and secondary data sources. Primary data includes: geomorphological, geological, and hydrological conditions. Secondary data used is Topographic Map data. The result of the study was in the form of a hydrogeomorphology of Zero Order Basin in Brau Village. Steep topography causes landslides, and water flows down gravitatively along the slope. The process of sedimentation occurs in a narrow depression zone located around seepage and springs. Tuffs and breccias (with cracks) cause high both porosity and permeability. Surface flow is not visible, but the baseflow occurs over the year. The baseflow that comes out as seepage and spring, is located in the bending area of the slope which has a narrow depression zone. The springs belt is formed at an elevation of 1,120-1,140 masl. The main function of Zero Order Basin in Brau Village is to accumulate water to form a complex river network system. Abstrak: Penelitian ini bertujuan untuk mendapatkan gambaran kondisi hidrogeomorfologi pada DAS Orde 0 (Nol) di Dusun Brau. Pendekatan kuantitatif digunakan dengan sumber data primer dan sekunder. Data primer mencakup: kondisi geomorfologi, geologi, dan hidrologi. Data sekunder yang digunakan adalah data Peta Topografi. Hasil kajian berupa deskripsi hidrogeomorfologi DAS Orde 0 (Nol) di Dusun Brau. Topografi curam mengakibatkan terjadinya longsor dan air mengalir secara gravitatif menuruni lereng. Proses sedimentasi terjadi pada zona depresi sempit di sekitar rembesan dan mata air. Tuff dan breksi (dengan retakan) menyebabkan tingginya porositas dan permeabilitas. Aliran permukaan tidak nampak, tetapi aliran dasar terjadi sepanjang tahun. Aliran dasar yang keluar sebagai rembesan dan mata air, berada pada daerah tekuk lereng yang memiliki zona depresi yang sempit. Sabuk mata air terbentuk pada elevasi 1.120-1.140 mdpl. Fungsi utama DAS Orde 0 (Nol) di Dusun Brau yaitu untuk mengakumulasikan air sebelum terbentuknya sistem jaringan sungai yang lebih kompleks.This is an open access article under the CC-BY-SA license.

This study aims to identify the potential groundwater in Jedong, Malang, East Java. The hydrogeomorphological approach is a suitable approach to describe the relationship between hydrological and geomorphological processes on and below the earth's surface. The survey of geoelectricity complements the hydrogeomorphological approach. It will give a better description of the groundwater conditions below the earth's surface. Based on the research, there are 2 hydrogeomorphological units in the study area, which are: Volcanic Foot Valley Unit and Volcanic Foot Ridge Unit. The best groundwater potential is in Volcanic Foot Valley Hydrogeomorphological unit, namely Awar-awar Valley and Cokro Valley. The valleys are dominated by gully erosion and landslides. They have surface deposits up to a depth of 7 meters, and lots of outcrops of breccia, pumice, and andesite boulders. The valley’s springs discharge between 56 - 198 m3/day. The average infiltration rate in the valley is 1776 mm / hour, with sandy soil material. The best aquifer consisting of sandy material is more than 10 meters in depth, based on the geoelectrical survey. Water in the aquiclude layer, cannot be exploited because it is breccia and tuff material. The Sawah valley cannot be exploited further because the groundwater potential is very low. This can be identified by the thick water outflow seepage. In the Volcanic Foot Ridge Hydrogeomorphological unit, the groundwater potential is also very small. Hydrogeomorphically, water will flow down the slope to the valley. It will reduce the infiltration rate. In general, the ridge area is only used for settlement, while the slopes are used for dryland agriculture. The geoelectric analysis results show that the groundwater potential is at a depth of more than 45 meters. This research’s results show that the combination of the hydrogeomorphological approach and the geoelectric use will provide a better description of the potential groundwater.