Claim Missing Document
Check
Articles

Found 9 Documents
Search
Journal : Agromet

EVALUASI DAMPAK PERUBAHAN PENGGUNAAN LAHAN TERHADAP VOLUME LIMPASAN STUDI KASUS: DAS CILIWUNG HULU, JAWA BARAT (EVALUATION OF LANDUSE CHANGE IMPACT ON RUN-OFF VOLUME CASE STUDY : CILIWUNG HULU WATERSHED, WEST JAVA) B. D. Dasanto; . Risyanto
Agromet Vol. 20 No. 2 (2006): December 2006
Publisher : PERHIMPI (Indonesian Association of Agricultural Meteorology)

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (746.555 KB) | DOI: 10.29244/j.agromet.20.2.1-13

Abstract

The upper Ciliwung watershed is one of the critical catchments areas in Java Island. A major element of this area is the modification of natural land-cover due to human activities. Land use change is driven by the interaction between physical and socio-economic factors. The objective of this paper is to develop a land use change model and to evaluate runoff volume based on land use prediction. The pseudo-R2 or 2 in this model is 51.7% and the calibration between predicted land use and the real is 65.5%. The analysis result of land use change for period 2005-2010 and 2015-2020 show a special change pattern. In the first period, the forest land will decrease by 85%, while resettlements land increase by 144%, so the Curve Number value will increase from 80 to 81. These indicate decreasing capability of the upper Ciliwung to retain rainfall. The impact of this condition will increase runoff volume from 660.000 m3 to be 905.000 m3. In the second period, the forest and resettlements land will increase by 612% and 28%, so the Curve Number will decrease from 80 to be 78. This will decrease runoff volume from 805.000 m3 to be 803.000 m3.
ESTIMASI NILAI LINGKUNGAN PERKEBUNAN KELAPA SAWIT DITINJAU DARI NERACA AIR TANAMAN KELAPA SAWIT (STUDI KASUS: PERKEBUNAN KELAPA SAWIT DI KECAMATAN DAYUN, KABUPATEN SIAK, PROPINSI RIAU)THE ESTIMATION OF OIL PALM PLANTATION ... Isa Teguh Widodo; Bambang Dwi Dasanto
Agromet Vol. 24 No. 1 (2010): JUNE 2010
Publisher : PERHIMPI (Indonesian Association of Agricultural Meteorology)

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (469.403 KB) | DOI: 10.29244/j.agromet.24.1.23-32

Abstract

Dayun area is one of the centers of oil palm plantation in Siak Regency. State-owned company that develops oil palm plantation in Dayun is PT Perkebunan Nusantara V (PTPN V) which is the first company developing oil palm plantation in Siak Regency. The oil palm plantations cause various effects to the environment; one of them is the decreasing water availability for the water stakeholders. The decreasing water availability causes additional cost to the community. The objectives of this study were to determine the decreasing of water availability which was caused by oil palm plantation, and its cost to meet the needs of water. The study used water balance model by Thornwhite 1957 and Willingness to Pays (WTP) analysis using questionaire of Contingent Valuation Method (CVM) in Sawit Permai, Dayun Subdistrict, Siak Regency. The land cover, before and after, affects the water balance which impacts the water availability in Dayun. The decreasing water availability was comparable with the increasing water demand in oil palm plantation, equal to 67 mm/year. Oil palm plantation had greater runoff than that of forest. The need of water in oil palm plantation in Dayun was 42.728 liters/ha/day, with the daily need of a single palm tree equal to 0,012 m3/s. Based on the analysis of debt estimation, there is debt decreasing which indicates the decreasing water availability in Dayun, around 349 m3/s yearly. The estimated value of the environment for oil palm plantation by water resources consumption based on the difference of forest and oil palm plantation during the dry season (JJA) is equal to Rp 7.500.000. Average WTP for the water conservation program is Rp 26.400, with WTP maximum and minimum up to Rp 45.000 and Rp 5.000, respectively. The economic value of water conservation program is Rp 18.850.000/month.Dayun area is one of the centers of oil palm plantation in Siak Regency. State-owned company that develops oil palm plantation in Dayun is PT Perkebunan Nusantara V (PTPN V) which is the first company developing oil palm plantation in Siak Regency. The oil palm plantations cause various effects to the environment; one of them is the decreasing water availability for the water stakeholders. The decreasing water availability causes additional cost to the community. The objectives of this study were to determine the decreasing of water availability which was caused by oil palm plantation, and its cost to meet the needs of water. The study used water balance model by Thornwhite 1957 and Willingness to Pays (WTP) analysis using questionaire of Contingent Valuation Method (CVM) in Sawit Permai, Dayun Subdistrict, Siak Regency. The land cover, before and after, affects the water balance which impacts the water availability in Dayun. The decreasing water availability was comparable with the increasing water demand in oil palm plantation, equal to 67 mm/year. Oil palm plantation had greater runoff than that of forest. The need of water in oil palm plantation in Dayun was 42.728 liters/ha/day, with the daily need of a single palm tree equal to 0,012 m3/s. Based on the analysis of debt estimation, there is debt decreasing which indicates the decreasing water availability in Dayun, around 349 m3/s yearly. The estimated value of the environment for oil palm plantation by water resources consumption based on the difference of forest and oil palm plantation during the dry season (JJA) is equal to Rp 7.500.000. Average WTP for the water conservation program is Rp 26.400, with WTP maximum and minimum up to Rp 45.000 and Rp 5.000, respectively. The economic value of water conservation program is Rp 18.850.000/month.
MODEL PERUBAHAN PENGGUNAAN LAHAN DAN PENDUGAAN CADANGAN KARBON DI DAERAH ALIRAN SUNGAI CISADANE, JAWA BARATLANDUSE CHANGE MODEL AND CARBON STOCK ESTIMATION IN CISADANE WATERSHED, WEST JAVA Antonio Alberto; Bambang Dwi Dasanto
Agromet Vol. 24 No. 2 (2010): DECEMBER 2010
Publisher : PERHIMPI (Indonesian Association of Agricultural Meteorology)

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (510.626 KB) | DOI: 10.29244/j.agromet.24.2.18-26

Abstract

Land use and land cover in Cisadane Watershed are very vulnerable to switch over, which is caused by the high rate of population growth.  Land use and land cover change cause the carbon stock changes. These changes were analysed using the logistic regression models, and in this analysis we used land use maps in 2001 and 2006. As many as 44 regression equations were developed with various values of determination coefficient (R2); 14% of the R2 was less than 0.50, 29% was between 0.50 and 0.75, and 57% is than 0.75. Statistically, there were 31 equations suitable to generate landuse map in 2010, 2015, 2020, and 2025. The amount of carbon stocks in Cisadane Watershed until the year 2025 tend to decrease, so the sum of carbon emissions in the atmosphere increased. This was mainly due to conversion of forest area into other landuse types. Land use and land cover in Cisadane Watershed are very vulnerable to switch over, which is caused by the high rate of population growth.  Land use and land cover change cause the carbon stock changes. These changes were analysed using the logistic regression models, and in this analysis we used land use maps in 2001 and 2006. As many as 44 regression equations were developed with various values of determination coefficient (R2); 14% of the R2 was less than 0.50, 29% was between 0.50 and 0.75, and 57% is than 0.75. Statistically, there were 31 equations suitable to generate landuse map in 2010, 2015, 2020, and 2025. The amount of carbon stocks in Cisadane Watershed until the year 2025 tend to decrease, so the sum of carbon emissions in the atmosphere increased. This was mainly due to conversion of forest area into other landuse types. 
ANALISA POTENSI WADUK RUKOH DALAM MEMENUHI KEBUTUHAN AIR DI KABUPATEN PIDIE, INDONESIAANALYSIS OF RUKOH RESERVOIR POTENCY FOR DETERMINING WATER REQUIREMENT IN PIDIE DISTRICT, INDONESIA Siti Nurdhawata; Bambang Dwi Dasanto
Agromet Vol. 25 No. 1 (2011): JUNE 2011
Publisher : PERHIMPI (Indonesian Association of Agricultural Meteorology)

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (296.918 KB) | DOI: 10.29244/j.agromet.25.1.9-16

Abstract

Generally, reservoir can overcome problem of water availability in particular region. The reservoir collects excess water during rainy season to be used at the time of water shortage during dry season. In Pidie, the largest water sources are from Krueng Baro Geunik and Krueng Tiro. The reservoir is located at Krueng Rukoh with Krueng Tiro as the source of water supply. The reservoir provides water for irrigating and supplying domestic water in Baro (11.950 ha) and Tiro (6.330 ha) areas. There are 13 districts (216718 inhabitants) use the water from this reservoir. Given the population growing at rate of 0.52% then the water demand in the region increases. The aim of study was to estimate the volume of water entering the reservoir using the tank model. Calibration curve between the tank model output and observation data showed good correlation (R2 = 0.7). The calibrated model was then used to calculate the discharge at Krueng Baro Geunik. A water balance analysis showed that the highest deficit occurred in September and the highest surplus in November. Based on this analysis, the capacity of Krueng Rukoh reservoir is able to fulfill its function assuming the rate of population growth and the irrigation area are constant.
Determination of Extreme Hydrological Index using HBV Model Simulation Results (Case Study : Upper Ciliwung Watershed) Isnayulia Lestari; Bambang Dwi Dasanto
Agromet Vol. 33 No. 1 (2019): JUNE 2019
Publisher : PERHIMPI (Indonesian Association of Agricultural Meteorology)

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (675.104 KB) | DOI: 10.29244/j.agromet.33.1.20-29

Abstract

The study of climate change on hydrological response is a crucial as climate change impact will drive the change in hydrological regimes of river. Upper Ciliwung watershed is one of the critical rivers in Java Island, which has been affected by climate change. This study aims to: (i) simulate the discharge flow using the Hydrologiska Byrans Vattenbalansavdelning (HBV) model; (ii) simulate future flow using three general circulation models (GCM) namely Commonwealth Scientific and Industrial Research Organisation (CSIRO) Mk.3.6.0, Model for Interdisciplinary Research on Climate version 5 (MIROC5), and Geophysical Fluid Dynamics Laboratory-Coupled Model generation 3 (GFDL-CM3); (iii) determine the changes of extreme hydrological index during historical period (2001-2015) and projected period (2031-2045). The historical year simulation and projections are used to determine eight hydrologic extreme indices for high flow and low flow. We calibrated the HBV model for two years (2001-2002) and validated it for two years (2003-2004). Our model performed well in discharge simulation as shown by the NSE values (0.66 for calibration and validation). Then we calculated the indices for each period used (historical and projected). To show the changes in hydrological regimes, we compare the indices between two periods. Changes in the index of the two periods tend to decrease in value on the index parameters that characterize the minimum extreme events. Hence, that it is possible in the projected period there will be extreme hydrological events in the form of drought.
Fire Danger on Jambi Peatland Indonesia based on Weather Research and Forecasting Model Lisnawati; Muh Taufik; Bambang Dwi Dasanto; Ardhasena Sopaheluwakan
Agromet Vol. 36 No. 1 (2022): JUNE 2022
Publisher : PERHIMPI (Indonesian Association of Agricultural Meteorology)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.29244/j.agromet.36.1.1-10

Abstract

Monitoring drought related to peat fire danger is becoming essentials due to the adverse impacts of peat fires. However, the current monitoring is mostly based on station data and has not yet covered all parts of peatlands. This research was carried out to initiate a spatial monitoring for peat fire, particularly in Jambi province. Our approach was simple by integrating Weather Research Forecasting (WRF) output with a drought-fire model. This research aims to: (i) calibrate rainfall, air temperature and soil moisture data from WRF output; and (ii) analyze temporal drought related to fire danger. A drought-fire model known as Peat Fire Vulnerability Index was applied with daily inputs of WRF output at 5km resolution, which were comprised of rainfall, air temperature, and soil moisture. The results showed that calibration reduced rainfall magnitude, and slightly increased the maximum air temperature and soil moisture. The calibration performance was good as shown by a very low percent bias (less than ±5%), and lower error (RMSE=16.5; MAE=9.5). Our analysis showed that drought triggered by El Niño in 2015 had escalated extreme fire danger class by 38% compared to normal year (2018). This has been confirmed by a low variation of proportion of extreme class during July-August 2015. The results suggested that integrating spatial global climate data will benefit to the improved drought-fire model by providing spatial data. The results are expected to be a reference on drought and peat fires mitigation action.
Bogor Water Adequacy Status for 2009-2019 Nita Tarigan; Perdinan; Bambang Dwi Dasanto
Agromet Vol. 36 No. 1 (2022): JUNE 2022
Publisher : PERHIMPI (Indonesian Association of Agricultural Meteorology)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.29244/j.agromet.36.1.42-50

Abstract

Water adequacy becomes one of the global concerns as the trend of population growth continues to arise. The condition of water adequacy can be worse in some regions since it also relates to rainfall, which is greatly influenced by global climate change. Here we explore water adequacy at local scale especially in Bogor, Indonesia based on sectoral water demands. The study aims to analysis water adequacy for 2009-2019 based on a climatic water balance. Water supply-demand analysis was performed using water usage index (WUI) in which high WUI corresponds to high critical water balance. Our results showed there was a deceased trend for water supply in Bogor approximately 0.6% per year, whereas an increased trend was observed for water demand (1.7% per year). The main contributor for the increased demand was from domestic water demand by 48%. Generally, water adequacy in Bogor for the period analysis (2009 -2019) is still adequate, but a proper management of water resource will ensure water adequacy in the long run in response to population explosion and climate change.
Evaluation of Flood Hazard Potency in Jakarta based on Multi-criteria Analysis RR Mashita Fauzia Hannum; I Putu Santikayasa; Bambang Dwi Dasanto
Agromet Vol. 36 No. 2 (2022): DECEMBER 2022
Publisher : PERHIMPI (Indonesian Association of Agricultural Meteorology)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.29244/j.agromet.36.2.101-111

Abstract

The frequency of flood events in Indonesia has increased since 1990, especially in the capital city of Jakarta. Flood events have affected socio-economic activities, and have threaten community health in flood prone areas. Although many efforts have been performed to reduced flood impacts, research on flood hazard remains a research challenge. This study aims to map level of flood hazard in Jakarta and to determine the most affected factors that cause flood. First, we defined factors that influence flood, and combined an analytical hierarchy process (AHP) to determine their weighted values and GIS approach to determine their score values. The combination of weight and score value determined the flood hazard index (FHI). The sensitivity analysis and validation then were applied to determine the robustness of the approaches. Our results show that the most influenced factors determining flood hazard were rainfall intensity, land use, and slope, whereas geology is the less factor. Based on the sensitivity analysis and FHI validation, our approaches were able to represent 59% flood disaster in Jakarta. The pattern of FHI value was high in north areas and low in south areas. The findings indicated that north areas are more flood prone than south areas. Further, this research contributes to the improved approach of flood mitigation in Jakarta
A Comparison of the Performance of the Weighted Ensembles Means in CORDEX-SEA Precipitation Simulations Aminoto, Tugiyo; Faqih, Akhmad; Perdinan; Koesmaryono, Yonny; Dwi Dasanto, Bambang
Agromet Vol. 38 No. 1 (2024): JUNE 2024
Publisher : PERHIMPI (Indonesian Association of Agricultural Meteorology)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.29244/j.agromet.38.1.19-35

Abstract

Numerous studies stated that the performance of ensemble mean derived from multiple climate models generally surpassed the individual member model, and applying weighting factors potentially increase the ensemble mean of performance. This study aims to assess the performance of unweighted and weighted ensemble means of 9-modelled precipitation datasets in the CORDEX-SEA multi-model simulations for 1981-2005. The 9 datasets included: CNRM_a, ECE_b, GFDL_b, IPSL_b, HadGEM2_a, HadGEM2_c, HadGEM2_d, MPI_c, and NorESM1_d. The weighting factors were derived from the models' skill scores measured using five statistical-based metrics, namely Taylor, Pierce (SS), Tian skill score (Tian), Climate prediction index (CPI), and Performance and Independence (PI). The ERA5 and GPCP precipitation datasets were used as the references for comparison. Then, reliable metrics will be used to determine the weighting factor. The results found that three metrics namely Taylor, SS, and Tian were more reliable than the other two metrics (CPI and PI). Spatially, the weighted ensemble mean based on a random method was superior to other ensemble mean methods and individual models. We found that the CNRM_a and GFDL_b models were spatially performed best. In contrast, most the ensemble means was temporally less performed compared to the individual model. Our findings suggested that by removal of low performance models will significantly influence on the overall ensemble model performance. Further, the research may provide valuable considerations of climate models selection for climate projection assessments, especially in the Southeast Asia region.