Cultural and geological heritage in time elapsed during historical Kingdoms in Yogyakarta Special Region, Indonesia

Yogyakarta, Indonesia is known for its kingdom government system for all its living history; since 8-10th century Mataram Hindu-Buddhist temples to the present Muslim Ngayogyokarto Hadiningrat. Those stretch of history resulted in many artefacts and chronicles. A cultural imaginary line that linking Merapi Volcano in the north and the Indian Ocean in the south through the Yogyakarta Palace in the middle has a sacral geo-cultural heritage, explaining a prosperity gentle volcanic town, a beautiful scheme of the open panoramic features with several temples standing on the plain and mountainous landscapes in between the rest of earthquakes and the volcanic eruptions. Many temples were partly buried under volcanic materials, and some others show evidence of being shaken several times by earthquakes. Boulders of volcanic materials varying in size and shapes are present in the plain of Yogyakarta, near Cangkiringan, Ngemplak and Ngaglik. Landslides exposed many geological features, such as faults, rock formation and stratigraphy, and some unstable slopes. Cultural and geological heritages at Yogyakarta Region were created over the time.

Modification Model of Soil Fertility Evaluation FAO-UNESCO on the Slopes of Merapi Volcano, Indonesia

One of the mountains known as active volcanoes in the world was Merapi volcano. From the very active impact of Merapi activity, there was a continuous addition of volcanic material associated with soil fertility, which can be evaluated using the Soil Fertility Evaluation (SFE) system. This study aims to obtain a more adaptive SFE system to the southern slopes of Merapi volcano by modifying the FAO- UNESCO version of SFE system that still uses linear equations. In this research used system of quadratic equation, use of natural logarithm (ln), and modification of new parameter. From the evaluation of soil fertility is then connected with the production component of paddy rice (dry grains crop). There were several indicators that used to see the quality of the model or test the goodness of fit of the model we make, for example from its R2. In this study the quality of a model was seen from: Akaike Info Criterion (AIC) and Schwarz Criterion (SC), and the data was done by using EViews 9. The results showed the parameters that influence big in the model can be seen from the correlation and influence the parameters in single. Quadratic equations can improve the quality of a model over a linear equation. The standard SFE model which is modified by using the nat

Real-Time Tephra Detection and Dispersal Forecasting by a Ground-Based Weather Radar

Tephra plumes can cause a significant hazard for surrounding towns, infrastructure, and air traffic. The current work presents the use of a small and compact X-band multi-parameter (X-MP) radar for the remote tephra detection and tracking of two eruptive events at Merapi Volcano, Indonesia, in May and June 2018. Tephra detection was performed by analysing the multiple parameters of radar: copolar correlation and reflectivity intensity factor. These parameters were used to cancel unwanted clutter and retrieve tephra properties, which are grain size and concentration. Real-time spatial and temporal forecasting of tephra dispersal was performed by applying an advection scheme (nowcasting) in the manner of an ensemble prediction system (EPS). Cross-validation was performed using field-survey data, radar observations, and Himawari-8 imageries. The nowcasting model computed both the displacement and growth and decaying rate of the plume based on the temporal changes in two-dimensional movement and tephra concentration, respectively. Our results are in agreement with ground-based data, where the radar-based estimated grain size distribution falls within the range of in situ grain size. The uncertainty of real-time forecasted tephra plume depends on the initial condition, which affects the growth and decaying rate estimation. The EPS improves the predictability rate by reducing the number of missed and false forecasted events. Our findings and the method presented here are suitable for early warning of tephra fall hazard at the local scale.

Real-Time Tephra Detection and Dispersal Forecasting by a Ground-Based Weather Radar

Tephra plumes can cause a significant hazard for surrounding towns, infrastructure, and air traffic. The current work presents the use of a small and compact X-band Multi-Parameter (X-MP) radar for the remote tephra detection and tracking of two eruptive events at Merapi Volcano, Indonesia, in May and June 2018. Tephra detection was done by analysing the multiple parameters of radar: copolar correlation and reflectivity intensity. These parameters were used to cancel unwanted clutter and retrieve tephra properties, which are grain size and concentration. Real-time spatial and temporal forecasting of tephra dispersal was performed by applying an advection scheme (nowcasting) in the manner of Ensemble Prediction System (EPS). Cross-validation was done using field-survey data, radar observations, and Himawari-8 imagery. The nowcasting model computed both the displacement and growth and decaying rate of the plume based on the temporal changes in two-dimensional movement and tephra concentration, respectively. Our results with ground-based data, where the radar-based estimated grain size distribution fell within the range of in-situ data. The uncertainty of real-time forecasted tephra plume depends on the initial condition, which affects the growth-and decaying rate estimation. The EPS improves the predictability rate by reducing the number of missed and false forecasted events. Our findings and the method presented here are suitable for early warning of tephra fall hazard at the local scale.

Student’s Level of Understanding on Mobile Learning based Volcano Eruption

This study aims to analyze student's level of understanding on mobile learning based volcano eruption. This research is quantitative descriptive. The sample were 200 students who lives in the area that affected by the eruption of Merapi Volcano (Magelang Regency, Sleman Regency, and Yogyakarta City), recruited using a simple random sampling. The instruments were online survey questionnaire of Student's Level of Understanding on Mobile Learning based Volcano Eruption. The distribution of the data is normal, reliable and homogen based the analysis used IBM SPSS Statistics 22 software. The results of this study indicate that students who lives in Merapi Volcano prone area have a good understanding about mobile learning based volcano eruption. Level of student's understanding on mobile learning meet a good criteria with percentage 72,80%, level of student's understanding on volcano eruption meet a good criteria with percentage 73,40%, and student's understanding on disaster mitigation meet a good criteria with higher percentage 76,40%.

Rethinking local genius of the Merapi’s community in eruption disaster risk reduction. Does it still work?

Merapi Volcano in Central Java which has a high level of activity still holds hazard potential in the future. To reduce the disaster risks, a good disaster management is required. People who live in hazardous areas possess important social capital to enhance disaster management, in the form of local genius to cope with eruption. However, a question arises whether local genius still exists and is accepted by members of the younger generation. This paper presents a discussion about the existence of local genius on the younger generation in the southwest region of Merapi Volcano. The data were collected using some techniques which include interviews, focus group discussions, and literature study. The data were analyzed descriptively supported with scoring and statistical analysis. The results of the study show that local genius is not widely recognized and understood by the younger generation. There are no differences on the understanding of local genius among young members of the society who differ in age. The lack of teaching about local genius between generations causes a low understanding of young generation on local genius. Despite having a high motivation for preserving local genius, the younger generation perceive the local genius as a socio-cultural assets rather than as a source which enhances a disaster management. Overall, this paper presents new insights to understand the existence of local genius among the younger generation.

Developing Sustainable Schools in the Shadow of Active Stratovolcano: A Study at Disaster-Prone Areas of Merapi Volcano

Education is a right for people that must be given to children, even in an emergency of eruption disaster. To ensure the sustainable education during the crisis situations, ideas on how to develop a sustainable school system in the stratovolcano area which is prone to eruption disaster are needed. This research was conducted at schools located in the western side of Merapi Volcano, attempting to provide alternative information about the potential and role of schools in providing education during emergency situations of eruption disaster. Data in the study were collected through interviews, observations, remote sensing image interpretations, and documentations. Data were analysed by scoring and spatial analysis using geographic information systems. The results of the study are as follows. First, schools have the potential to provide education during the disaster emergency situations. School potential consists of physical infrastructure and human resource potential in the form of the role of the principal and teachers. Second, most of the level of school preparedness in facing disasters is still in the low category. This needs to be strengthened to ensure that the schools continue to function during the crisis period. Last, a division of roles in the sister school system is needed based on the location of the school toward the eruption centre. The schools in the safe zone act as a buffer for schools in vulnerable areas. Overall, schools have the potential to keep running the learning process during the crisis periods. This requires good management through the sister school system within the framework of sustainable school initiatives.

Disaster Risk Analysis of Merapi Volcano Eruption in Cangkringan District Sleman Regency

Abstrak Cangkringan is located in the Merapi Volcano Disaster Prone Areas which has the potential to be affected by eruption. The eruption of Merapi Volcano is a consequence that must be faced by the local resident, so that the need for disaster risk analysis in the region through research is a must. This disaster risk analysis research aims to (1) Analyze the risk level of Merapi Volcano eruption in Cangkringan. (2) Analyze the risk distribution of Merapi Volcano eruption in Cangkringan.This research is a descriptive research with a quantitative approach conducted in Cangkringan District, Sleman Regency, Special Region of Yogyakarta. The population in this study is the entire village in Cangkringan. The entire area is the subject of this research. The variables of this reseach are hazard, vulnerability and capacity. This study used primary data and secondary data. Data collection techniques used are observation, interviews, and documentation. Data analysis techniques used are scoring, overlay and descriptive.The results of this study indicate: (1) The level of risk of Merapi Volcano Eruption in Cangkringan is divided into four levels which are high, medium, low and very low. The area of Cangkringan has a high level of risk covering an area of 19,00% of the total area, the medium-risk level is 38,38% of the total area, the low-risk level is 16,61% of the total area, the very low-risk level is 20,23% of the total area of Cangkringan District. The higher the level of disaster risk, the greater the potential loss due to the eruption of Merapi Volcano. (2) The distribution of disaster risk of Merapi Volcano Eruption in Cangkringan is in the entire village. The distribution of high-risk level is in part of Umbulharjo Village, part of Glagaharjo Village and part of Argomulyo Village. The distribution of medium-risk level is in part of Umbulharjo Village, part of Kepuharjo Village and part of Glagaharjo Village. The distribution of low-risk level is in part of Kepuharjo Village, part of Wukirsari Village and part of Argomulyo Village. The distribution of very low-risk level is in part of Wukirsari Village and part of Argomulyo Village.

The potential of river discharge at the peak of the dry season in some disaster-prone area of Merapi Volcano

With a high level of volcanic activity and many people living in the disaster-prone area, sustainable disaster management in the Merapi Volcano area is still very much needed in the future. One of the needs in building disaster management is ensuring water resources available during the pre-eruption period. So far, springs are the primary source of water that has been widely used by residents in the volcanic foothills, which are prone to eruption disasters. However, at the time of the eruption, many springs were not functioning so that alternative water sources were needed. River water can be an alternative water source, and a study of river water's potential is required to ensure its feasibility. This study was conducted on the south to the southwest side of Merapi Volcano to analyze the quantity and quality of river water as an alternative water source. Data collected through observation, literature study, and document search. Data analysis performed using descriptive analysis, matching analysis, and statistical analysis using independent sample t-test and simple linear regression. The study results show that seven rivers in the south to the southwest slope can be used as water sources because they are not lava flows. These rivers have varying discharge and water quality. There is no difference in discharge and water quality between the top and the bottom of the volcano foot. When dry season is on the peak, three rivers have no flow because some springs locations are at the volcano's bottom. Overall, based on these findings, it can be emphasized that the use of water sources is needed to do at the closest point to the evacuation barracks. However, a water treatment installation needs to be provided in the evacuation barracks so that the river water is suitable for consumption.