Suprajaka Suprajaka

Dr. Suprajaka Suprajaka

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Research Focus & Metrics

Academic Career Length

5Years (2022-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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8 June 2022 in Journal of Water and Land Development
Verified
Journal Article
Closed access
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Wiwin AmbarwulanWiwin Ambarwulan
Wiwin Ambarwulan
INIrmadi Nahib
Irmadi Nahib
WWWidiatmaka Widiatmaka
Widiatmaka Widiatmaka
RDRatna Sari Dewi
Ratna Sari Dewi
SMSri Lestari Munajati
Sri Lestari Munajati
SSSuprajaka Suprajaka
Suprajaka Suprajaka
Land suitability assessment is an important stage in land use planning that guides the direction of optimal land use. The objective of this study was to select a suitable location for settlements in earthquake-prone areas using the integration of the Analytical Hierarchy Process (AHP) and Geographical Information System (GIS). In total, six maps were considered to determine a suitable location for settlements, namely topography, soil, geology, land cover/land use, a regional spatial planning pattern map, and an earthquake vulnerability map. The results showed that in medium earthquake-prone areas, the suitable land area which are available for settlement was 90.25 km2 (46.36% of the total land area available – 194.68 km2). Whereas in highly earthquake-prone areas, the suitable and available land area was 528.11 km2 (70.25% of the total land area in the high vulnerability zone – 751.81 km2). The research proved that AHP and GIS integration is very effective and robust for mapping land suitability in earthquake-prone areas. The results of the analysis can be used by planners to prioritize settlement development in the Sukabumi regency. The methodology developed is recommended to be applied in selecting locations for settlements in other parts of Indonesia.

31 January 2026 in Resources
Verified
Journal Article
Open access
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INIrmadi Nahib
Irmadi Nahib
Yudi WahyudinYudi Wahyudin
Yudi Wahyudin
WWWidiatmaka Widiatmaka
Widiatmaka Widiatmaka
STSuria Tarigan
Suria Tarigan
Wiwin AmbarwulanWiwin Ambarwulan
Wiwin Ambarwulan
BWBambang Winarno
Bambang Winarno
Rapid land use and land cover (LULC) changes in densely populated watersheds pose serious challenges to the sustainability of ecosystem services (ES), yet their spatially explicit economic consequences remain insufficiently understood. This study analyzes the spatio-temporal dynamics of LULC and ecosystem service values (ESVs) in the Citarum Watershed, Indonesia, one of the country’s most critical and intensively transformed watersheds. Multi-temporal Landsat imagery from 2003, 2013, and 2023 was classified using a Random Forest algorithm, while future LULC conditions for 2043 were projected using a Multi-layer Perceptron–Markov Chain (MLP–MC) model under three scenarios: Business-as-Usual (BAU), Protecting Paddy Field (PPF), and Protecting Forest Area (PFA). ESVs were quantified at multiple spatial scales (county, 250 m grids, and 100 m grids) using both the Traditional Benefit Transfer (TBT) method and a Spatial Benefit Transfer (SBT) approach that integrates biophysical indicators with socio-economic variables. The contribution of LULC transitions to ESV dynamics was further assessed using the Ecosystem Service Change Intensity (ESCI) index. The results reveal substantial historical forest and shrubland losses, alongside rapid expansion of settlements and dryland agriculture, indicating intensifying anthropogenic pressure on watershed functions. Scenario analysis shows continued degradation under BAU, limited mitigation under PPF, and improved forest retention under PFA; although settlement expansion persists across all scenarios. Total ESV declined from USD 2641.33 million in 2003 to USD 1585.01 million in 2023, representing a cumulative loss of 46.13%. Projections indicate severe ESV losses under BAU and PPF by 2043, while PFA substantially reduces, but does not eliminate economic degradation. ESCI results identify forest and shrubland conversion to settlements and dryland agriculture as the dominant drivers of ESV decline. These findings demonstrate that integrating multi-scenario LULC modeling with spatially explicit ESV assessment provides a more robust basis for ecosystem-based spatial planning and supports sustainable watershed management under increasing development pressure.

22 March 2024 in Journal of Water and Land Development
Verified
Journal Article
Open access
PDF file
JSJaka Suryanta
Jaka Suryanta
INIrmadi Nahib
Irmadi Nahib
Fadhlullah RamadhaniFadhlullah Ramadhani
Fadhlullah Ramadhani
Farid RifaieFarid Rifaie
Farid Rifaie
Nawa SuwediNawa Suwedi
Nawa Suwedi
SSSuprajaka Suprajaka
Suprajaka Suprajaka
Exploring the drivers of changes in ecosystem services is crucial to maintain ecosystem functionality, especially in the diverse Central Citarum watershed. This study utilises the integrated valuation of ecosystem service and trade-offs (InVEST) model and multiscale geographically weighted regression (MGWR) model to examine ecosystem services patterns from 2006 to 2018. The InVEST is a hydrological model to calculate water availability and evaluate benefits provided by nature through simulating alterations in the amount of water yields driven by land use/cover changes. Economic, topographic, climate, and vegetation factors are considered, with an emphasis on their essential components. The presence of a geographical link between dependent and explanatory variables was investigated using a multiscale geographic weighted regression model. The MGWR model is employed to analyse spatial impacts. The integration of both models simplified the process and enhanced its understanding. The findings reveal the following patterns: 1) decreasing land cover and increasing ecosystem services demand in the watershed, along with a decline in water yield, e.g. certain sub-districts encounter water scarcity, while others have abundant water resources; 2) the impact of natural factors on water yield shifts along vegetation > climate > topography (2006) changes to climate > vegetation > topography (2018).