Indonesian Journal of Geography
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Incremental planning of the location of public health facilities in a rural region
Get PDFSome people in rural areas are often excluded from using health facilities in developing nations due to political interference in facility location decision-making. Limited attention has been paid in the literature to promoting inclusiveness in public facilities usage in developing nations. Therefore, this study was designed to examine the access to Primary Health Centres (PHCs) in the Yewa region, Nigeria. Data on the 509 settlements and 91 PHCs in the Yewa region were obtained from government directories. The p-median Location-Allocation model was used for data analyses. The study showed that the number of PHCs increased and access to them improved in the Yewa region between 1991 and 2019. It was also shown that inclusiveness in facilities could be promoted by optimally adding new PHCs. The study assessed the effectiveness of past locational decisions, similar to other studies in Bangladesh and India, and revealed that the military administration performed better than the civilian administration in facility location decision-making between 1991 and 2019. The study showed how new facilities could be optimally located to improve access and inclusiveness in public usage
Comparison of Various Spectral Indices for Optimum Extraction of Tropical Wetlands Using Landsat 8 OLI
No full textThis research specifically aims to investigate the most accurate spectral indices in extracting wetlands geospatial information taking South Kalimantan, Indonesia, as an example of wetlands in tropical areas. Ten spectral indices were selected for testing their ability to extract wetlands, those are NDVI, NDWI, MNDWI, MNDWIs2, NDMI, WRI, NDPI, TCWT, AWEInsh, andAWEIsh. Tests were performed on Landsat 8 OLI path/row 117/062 and 117/063. The threshold method which was used to separate the wetland features from the spectral indices imagery is Otsu method. The results of this research showed that generally MNDWIs2 was the most optimal spectral indices in wetlands extraction. Especially tropical wetlands that rich with green vegetation cover. However, MNDWIs2 is very sensitive to dense vegetation, this feature has the potential to be detected as wetlands. Furthermore, to improve the accuracy and prevent detection of the dryland vegetation as wetlands, the threshold value should be determined carefully
Change Detection of Benthic Habitat Communities using Landsat Imageries in Wakatobi Islands from 1990 to 2017
No full textCurrently, coral reef and seagrass ecosystems in Wakatobi Islands are categorized as 'poor' because the coverage of the healthy coral is less than 50%. Therefore, detailed information about their condition through time is needed to prevent coastal degradation. Time-series analysis of Landsat images recorded in 1990, 2000, 2010, and 2017 is expected to provide information on coral reefs' habitat in Wakatobi Islands over the studied period. This study aims to determine areas that experience drastic changes in benthic habitat cover and analyze the dynamics of the changes. The image processing procedures used in this study are image correction, image classification, and applying the Change Detection Model. The image correction consists of geometric, sunglint, and water column correction, while the change detection model uses SPEAR Tools in ENVI software. The results showed a precise location that experienced a drastic change in benthic habitat cover and the changes in benthic habitat classes every ten years, which started from 1990 to 2017
Rainfall variability analysis using Precipitation Concentration Index: a case study of the western agro-climatic zone of Punjab, India
No full textDue to climate change, the rainfall pattern has changed, which ultimately either cause flood or drought in any region of the world. Hence, a rainfall variability analysis helps to manage the water resources better. Rainfall variability analysis of a long term at particular area reveals vital information about past and future climate. The study's objective was to analyse the rainfall variability and intensity of long term monthly rainfall data (1982–2018) using the Precipitation Concentration Index (PCI). Data was collected from Punjab Agricultural University, Regional Research Station, located at Bathinda, India. The PCI was calculated for the annual, winter, pre-monsoon, monsoon, post-monsoon season, and decadal scale. Results have outlined that PCIAnnual ranges from the lowest of 14.96 in 2006 to the highest of 43.82 in 2000, and the average of 37 years is 23.22. About ≈59.5% of the year PCIAnnual was characterised by Strong Irregularity of Precipitation Distribution (SIPD, PCIAnnual> 20), an indication of SIPD within the 37 years. While ≈2.7% of the year recorded annual value within the moderate irregular range (10<PCIAnuual<15), which indicates an irregular rainfall distribution (MIPD) and concentration across the months. Similarly, the precipitation concentration in China was also found strongly irregular in the western and northern parts of the northwest and the northern region of the Tibetan Plateau. The study recommends that the Bathinda Development Authority (BDA) may use and adopt these results and redevelop the existing groundwater recharge structures (pond) and artificial recharge structures
The Assessment of Groundwater Vulnerability towards Contamination using the DRASTIC and NV Indexes in Banjarbaru City, South Borneo, Indonesia
Get PDFThe current excessive use of groundwater is exacerbated by human activities, which directly or indirectly trigger surface pollution and gradually affect to the subsurface, including groundwater. Indonesia is one of the developing countries that encounter these obstacles, specifically Banjarbaru City in South Kalimantan Province and its surroundings. Hence, proper management is needed to maintain the sustainable function of groundwater, such as by determining its vulnerability index to pollution. This study used geospatial analysis to determine the intrinsic and extrinsic vulnerability of groundwater via the DRASTIC and NV index methods, respectively, through visual representations on a map. The validation involved the distribution of nitrate and nitrite values to review the relationship between vulnerability levels and the presence of anthropogenic influences. Subsequently, the results of the DRASTIC method showed that the study area is included in three vulnerability indexes, namely low (95-120), medium (120-160), and high (160-186). The NV method further indicated that the groundwater vulnerability indices are divided into four, namely very low (21.2-70), low (70-110), moderate (110-150), and high (150-186). Based on the results, the use of specific vulnerabilities was considered more effective than the intrinsic technique in determining the vulnerability index because the NV method considers land use as a parameter to provide more detailed outcomes
Greenhouse Gas Emission from Rice field in Indonesia: Challenge for future research and development
Get PDFRice is an essential crop in Indonesia. Any aspects of rice to increase productivity have been well studied and documented; however, there are still lacking well-documented studies on its environmental aspects, including climate change. Many researches might already be conducted, but only a few have been published in a peer-reviewed journal. There is still a lack of robust data on greenhouse gas (GHG) emissions from the rice field in Indonesia, factors affecting and the technology on how to reduce it. From the reviewed publications, it was found out that research only conducted under a controlled environmental setting. More research on understanding the controlling factors (e.g., water management, rice cultivar, soil types, and fertilizer) of GHG emission from rice field is still needed. The result will introduce a sustainable farming practice, with low in GHG emissions, high in productivity, simple to apply and generate more income to farmers. This review has identified the gaps for future research and development in Indonesia. The research should meet the need, either national or global strategies. Development of a new farming practice will succeed in the presence of government policies. Therefore an intensive interdisciplinary approach between researcher and other stakeholders should be conducted
The Impact of the Interaction between Madden-Julian Oscillation and Cold Surge, on Rainfall over Western Indonesia
No full textThe Madden-Julian Oscillation and Cold Surge phenomena have been known to cause increased rainfall, with the capacity to trigger hydrometeorological disasters, in western Indonesia. However, further investigations are required regarding the interaction between these phenomena on rainfall pattern. Therefore, this study aims to analyze the interaction between MJO and CS over western Indonesia, particularly by using land-based rainfall observation data from multiple stations, as previous studies were dominated by the use of gridded data from remote observations. This study utilized in-situ observation data obtained from 4329 weather observations and rain stations between 1989 and 2018. Subsequently, quality control performed based on data availability exceeding 70% over a 30-year period resulted in 303 selected stations to be used for further analysis. Meanwhile, the RMM index, as well as reanalysis data of mean sea level pressure and 925 hPa meridional wind, were also applied for MJO and CS identification. According to the composite analysis, the effect of CS on MJO phases tends to increase precipitation by about 50%, over western Indonesia, with maximum increase ranging from 200 to 400% over the northeastern coast of Sumatra, around Karimata Strait (Riau Islands and West Kalimantan), as well as the northern coast of Java. These areas are exposed to the sea and have direct access to the wind-terrain interaction. In addition, the highest rainfall anomaly due to the MJO-CS interaction occurs around Karimata Strait, followed by northern Sumatra and Java, with spatially averaged rainfall anomaly reaching 5 mm/day over the area
Unregistered artesian Well Management in Pasuruan, Indonesia: An Attempt to Protect Groundwater Resources
No full textThe number of unregistered artesian wells increases every year in the northern slopes of Bromo Volcano, Pasuruan. Artesian wells are used for domestic needs and agricultural irrigation but are not followed by environmentally sound groundwater use. The purpose of this study is to assess the potential for groundwater, groundwater use, wasted groundwater, and recommendations for groundwater management. The groundwater potential was obtained by measuring the depth of the groundwater table, piezometric surface of artesian wells, and geoelectrical data. Water uses were obtained from calculations based on the Indonesian National Standard. The amount of wasted groundwater was obtained by comparing the groundwater potentials, groundwater uses, and groundwater discharges from unregistered artesian wells. Water transfer was assessed by selecting unregistered artesian wells with discharges able to fulfill the water demands of each village. Groundwater in the Sub-Districts of Gondang Wetan and Winongan has high potential consisting of 1 unconfined aquifer group and two confined aquifer groups. Gondang Wetan and Winongan Sub-Districts are characterized as wasting groundwater potential through unregistered artesian wells. The discharge flow of unregistered artesian wells exceeds the water needs (>100%) in Winongan and Gondang Wetan Sub-Districts. Groundwater can be managed by water transfer, closure of artesian wells, and regulation of artesian wells use. Water can be transferred to areas not covered by Artesian wells in 20 villages. The number of artesian wells used for water transfer is 20 with a discharge of 5-20 liters/s.
The Risk of Non-Communicable Diseases after being Exposed to the Urban Flood; A Literature Review and Meta-Analysis
No full textBackground: Risk mapping for the various types of non-communicable diseases (NCDs), which lead to the cause of death due to the impact of the urban flood, is rarely conducted. The study aimed to conduct a Systematic Literature Review (SLR) and meta-analysis of the risk of various NCDs after the community experienced the urban flood disaster. Methods: The data was taken from PubMed, ScienceDirect, Taylor and Francis, and ProQuest from June 2010 to June 2020 by searching for the words of flood and NCDs that only occurred in urban areas. This study refers to the guideline that is widely used to conduct meta-analysis research, namely PRISMA. The procedure was started by searching, screening, and validating the original articles through meta-analysis using R Studio. Result: Twenty-six original articles were selected for SLR, and only two articles were not eligible for meta-analysis. Mental illness (0.53, 95% CI, 0.33-0.68), heart problems (0.39, 95% CI -0.11-0.73), and respiratory problems (0.53, 95% CI, 0.02-0.82) are the NCDs categories occurring after the community, predominantly female and the community aged >40 years, was exposed to the urban flood. This risk magnitude finding complements the previous studies that only did a literature review. The heterogeneous result (tau^2 p-value>0.05) and bias effects of publication (Egger test p-value>0.05) indicated that immediate assistance for victims is essential to prevent the onset of NCDs. Conclusion: Without early prevention and urban planning, the urban flood disaster can contribute to mental illness, heart problems, and respiratory problems
Detection of Potential Fishing Zones of Bigeye Tuna (Thunnus Obesus) at Profundity of 155 m in the Eastern Indian Ocean
Get PDFRemotely sensed data and habitat model approach were employed to evaluate the present of oceanographic aspect in the Bigeye tuna's potential fishing zone (PFZ) at a profundity of 155 m. Vessel monitoring system was employed to acquire the angling vessels for Bigeye tuna from January through December, 2015-2016. Daily data of sub-surface temperature (Sub_ST), sub-surface chlorophyll-a (Sub_SC), and sub-surface salinity (Sub_SS) were downloaded from INDESO Project website. Vessel monitoring system and environmental data were employed for maximum entropy (maxent) model development. The model predictive achievement was then estimated applying the area under the curve (AUC) value. Maxent model results (AUC>0.745) exhibited its probable to understand the Bigeye tuna's spatial dispersion on the specific sub-surface. In addition, the results also showed Sub_ST (43,1%) was the most affective aspect in the Bigeye tuna dispersion, pursued by Sub_SC (35,2%) and Sub_SS (21,6%)