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The ever-increasing economic and population growth closely relates to the change in land cover. As a region grows, the land cover shifts from forests to agriculture and further to developed areas. Such a gradual change occurs slowly; however, understanding the land cover dynamics is essential to regional planning, especially in developing regions, including Indonesia. Despite its importance, studies on land cover changes in developing regions lack a coherent dataset, as many studies are based on ad-hoc approaches, resulting in embedded uncertainties. An example is the land cover classification using LANDSAT data in many parts of the developing countries lacking consistency. As an alternative, the MODIS dataset is a relatively new dataset produced by NASA, presenting a standardized land cover dataset with a 500×500 m resolution at global coverage. Such a standardized dataset gives consistency in land cover dynamics and future projections. This study presents the potential of MODIS and its use case in understanding land cover dynamics in an urbanizing watershed, i.e., the Majalaya Watershed in West Java, Indonesia. The study presents the use of Markov Chain Analysis in understanding the tendency of changes between land cover classes. This study also indicates future research directions to enrich the topic further.

Flooding is a major problem in Indonesia, with a need for a more data-driven model to understand the sources of floods and potential measures. As ground-based data availability and quality are major sources of uncertainty in flood modeling in such a developing country, satellite-based data is one significant option to complement the drawbacks of ground-based data. The data available from the satellite data still needs to be calibrated with the ground-based observation data. This research uses satellite rainfall data from GSMaP (Global Satellite Mapping and Precipitation) by JAXA and the quantile mapping method to calibrate the satellite rainfall data with local rainfall observation. The quantile method is a bias correction method frequently used for precipitation and temperature variables. This method investigates the bias in regional satellite rainfall data and local rainfall observation. The satellite and ground-based data scales are changed to quantiles or percentiles to calculate the correction factors. The quantile mapping method aims to determine the closely fitted CDF curve between the satellite and the ground-based rainfall data. The study area is Majalaya, one of the regencies in West Java known as the metropolitan city for the textile industry and agriculture center. The Quantile Mapping method successfully calibrated the GSMaP rainfall data in Majalaya with an R2 of 0.996. This research can solve the problem of rainfall data in Indonesia and can further be developed for other purposes, such as flood analysis and prediction.

Prevention of stress in the asymptomatic stage of the plants could result in improved crop management. In this study, the water and light stress of three oil palm seedlings (Elaeis Guineensis) was examined by assessing the leaves' colour using CIELAB colour space. The oil palm seedlings were subjected to water stress for 33 days and then to water and light stress from 55 to 78 day (for 25 days). The variation of the colour of the leaves due to water stress was discussed in detail. The approach used in this study to identify the drought stress may allow for differentiating mild environmental and severe drought stress in oil palm plants and may be used for remote field-scale estimation of plant stress resistance and health.

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.

Titanium dioxide (TiO2) is an attractive semiconductor oxide compound due to its good stability properties both in chemical and photochemical. TiO2 in the form of nanofibers offers many advantages such as high surface area, flexibility of structures and mechanical properties such as stiffness and tensile strength. In this study, we reported the synthesis of TiO2 nanofibers using electrospinning technique. TiO2 nanofibers were produced from titanium (IV) iso-propoxide precursor solution at different applied voltages of 10 kV and 12 kV, while the flowrate was kept constant at 0.7 ml/hours during the process. The electrospinning process produced a thin layer of nanofibers which was then calcined for 1 hour at different calcination temperature. Based on the SEM images, we found that at applied voltage of 12 kV uniform and continuous nanofibers had already formed with the average diameter of nanofibers was in the order of sub microns. The diffraction pattern of TiO2 nanofibers shows that at a calcination temperature of 450°C, the phase was dominated by the anatase phase, while at 500°C it has a combination of anatase and rutile phases. Based on UV-Vis spectroscopy, it was found that the energy gap of TiO2 nanofibers calcined at temperature of 450°C and 500°C were 3.32 eV and 3.22 eV, respectively.

The low-cost quartz crystal microbalance (QCM) instrument with the microcontroller as the basis of the embedded system of the frequency counter was implemented. The system uses a quartz crystal transducer from the crystal oscillator component. The frequency shifting was observed and analysed in association with some experimental tests. The experiments such as ethanol evaporation, water vapor in the humidity chamber, and coating the surface with TiO2 particles had been conducted. The developed QCM instrument has shown the ability to measure the frequencies in response to the addition or reduction of mass on the surface of the crystal oscillator. These responses are caused by evaporation, humid condition, and deposited particle on the quartz crystal surface. The QCM was varied into two initial frequencies, 5 and 10 MHz. The 5 MHz system represents the proper “in range” frequency counters, inside a counting limit of the microcontroller up to 5.6 MHz. On the other side, the 10 MHz is an experimental development system. Both types utilise a D flip-flop frequency divider that made a microcontroller-based frequency counter and can count the frequency twice the limit. The more stable 10 MHz have shown promising potential application related to the surface interaction with other material and can hold thicker deposition on its surface with a better stability response than the lower frequency counterpart.

Indonesia has 16.100 islands and 92 is outermost islands. These small islands are currently experiencing the impact of climate change from sea level rise and global warming. This study aims to determine vulnerability of small island through changes in coastline and dynamic change of area due to climate change especially from coastline changes. Nineteen islands selected as representation of Indonesia seas regions. The data were collected from satellite images range from 2000 to 2020. To analyze, this research method uses Coastsat method to detect coastlines and QGIS to process coastline data and change of the island areas. The results of this study indicate that the average reduction in the area of small islands in Indonesia reaches 5.084% for approximately 20 years. Overall, the change in the area shows that most of the small outermost islands in Indonesia have Medium vulnerability

Bengkulu, as part of Sumatra, receives less attention for its odonatological aspect during the current advance of life science. Historical records on Odonata were contributed by many foreign researchers from Dutch colonial era, including accounts provided by Lieftinck and Ris. In order to compile Odonata database for Bengkulu, there have been conducted dragonfly surveys from two years ago at some representative sites in this province. Conservation area of Seluma in the southern Bengkulu was visited in 2019 for two weeks survey, while conservation area of Lemo Nakai was surveyed in 2020 for the same work duration. Random survey and continuous citizen science have been performed at Bengkulu City to further the database from human impacted area. Thirty-five species were recorded from Seluma, thirty-nine were from Lemo Nakai and ten species were observed to exist within the human impacted area in Bengkulu City. In total, there were total 52 dragonfly species recorded within the administrative boundary of Bengkulu Province which more than half of historical Odonata records for this province. Thirty-one species belonged to Anisoptera (true dragonflies) and twenty-one species are grouped into Zygoptera (damselflies). Some noteworthy records are highlighted in this paper, such as the rare Dysphaea dimidiata (Euphaeidae), Anax panybeus (Aeshnidae) and Orthetrum schneideri (Libellulidae); Sumatran endemic Heliocypha angusta angusta (Chlorocyphidae) and Megalogomphus sumatranus (Gomphidae); as well as the observation of three Aeshnid species within human settlement in Bengkulu City. Further details on prominent Odonata species were also outlined along with their significances.