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Hadmoko Danang Sri de Belizal Edouard Mutaqin Bachtiar Wahyu Dipayana Gilang Arya Marfai Muh Aris Lavigne Franck Sartohadi Junun Worosuprojo Suratman Starheim Colette C. A. Gomez Christopher 《Natural Hazards》2018,94(1):419-444
Following the 2010 VEI 4 eruption of Merapi volcano, more than 250 lahars were triggered during two rainy seasons from October 2010 to March 2012. This high number of post-eruption lahars mainly occurred in the Kali (valley) Putih watershed and was mostly associated with high-magnitude rainstorms. A lahar occurring on January 8, 2011, caused significant damage to homes in several communities, bridges, sabo dams, and agricultural crops. The aims of this contribution are to document the impacts of lahars on the Kali Putih watershed and specifically (1) to analyze the lahar frequency during the period of 1969–2012 on an inter-annual and intra-annual basis and to determine the link between the volume of tephra and the frequency of lahars; (2) to detail the lahar trajectory and channel evolution following the January 8th lahar; (3) to map the spatial distribution of the thickness and geomorphic effects of the lahar deposit; and (4) to determine the impacts of the lahar on the infrastructure (sabo dams and roads) and settlements in the distal area of the volcano. The Kali Putih watershed has experienced 62 lahars, which represent 22% of all lahars triggered on 17 rivers at Merapi between 2010 and 2012. The main geomorphic impacts are: (1) excessive sedimentation in valleys, settlements and agricultural areas; (2) undercutting of the river banks by as much as 50 m, accompanied by channel widening; and (3) abrupt changes in the river channel direction in the distal area (15–20 km downstream of the volcano). About 19 sabo dams were damaged, and 3 were totally destroyed. Over 307 houses were damaged, and the National Road Yogyakarta–Semarang was regularly cut (18 times during approximately 25 days). Although the sabo dams on Kali Putih were originally constructed to protect distal areas from lahar damage, they had little effect on the 2010–2012 rain-triggered lahars. The underlying design of those dams along this river is one of the main reasons for the major destruction in this sector of the volcano’s lower slope. The catch basin capacity of the sabo dam was only 1.75?×?106 m3, whereas the total volume of the 2010–2011 lahars exceeded 5?×?106 m3. In order to prepare for future lahars, the government has invested in significant mitigation measures, ranging from structural approaches (e.g., building new sabo dams and developing an early warning system) to non-structural approaches (e.g., contingency and preparedness planning and hazard education).
相似文献2.
Mohd Khairul Nizar Shamsuddin Wan Nor Azmin Sulaiman Saim Suratman Mohamad Pauzi Zakaria Kamarudin Samuding 《Arabian Journal of Geosciences》2014,7(9):3731-3753
The bank infiltration (BI) technique may be a viable option if the local climate, hydrological, and geological conditions are conducive. This study was specifically conducted to explore the possibility of using BI to source the polluted surface water in conjunction with groundwater. Three major factors were considered for evaluation: (1) investigation on the contribution of surface water through BI, (2) input of local groundwater, and (3) water quality characteristics of water supply. Initially, the geophysical method was employed to define the subsurface geology and hydrogeology, and isotope techniques were performed to identify the source of groundwater recharge and interaction between surface water and groundwater. The physicochemical and microbiological parameters of the local surface water bodies and groundwater were analyzed before and during water abstraction. Extracted water revealed a 5 %–98 % decrease in turbidity, as well as HCO3 +, SO4 ?, NO3 ?, Al, As, and Ca concentration reduction compared with those of Langat river water. However, water samples from test wells during pumping show high concentrations of Fe2+ and Mn2+. In addition, amounts of Escherichia coli, total coliform, and Giardia were significantly reduced (99.9 %). Pumping test results indicate that the two wells (DW1 and DW2) were able to sustain yields. 相似文献
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Mohammed Ilyas Arunsala Pandy Mohd. Suhaimi Jaafar 《Journal of Atmospheric Chemistry》2001,40(2):111-121
The South-East Asian region experienced a haze episode in 1994 which was widely believed to be due to widespread forest fires in Sumatra and Kalimantan (Indonesia). Broadband measurements of the surface level solar ultraviolet-B, UV-A and Global radiation at Penang (Malaysia) are used to study the effect of the 1994 haze on effective UV-B irradiance. We find that during the haze episode, there is enhanced absorption of surface level UV-B radiation. The effect of haze on UV-A and Global radiation is much less. The reduction in absolute noon time UV-B irradiance (mostly cloud free) during the 1994 haze period was 23% relative to the UV-B irradiance during thecorresponding haze-free period in 1995. Even though the noon time radiation data minimizes the cloud effect in the results presented some cloud effect is still present. 相似文献
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Groundwater and surface-water utilisation using a bank infiltration technique in Malaysia 总被引：1，自引：1，他引：0
Mohd Khairul Nizar Shamsuddin Wan Nor Azmin Sulaiman Saim Suratman Mohamad Pauzi Zakaria Kamarudin Samuding 《Hydrogeology Journal》2014,22(3):543-564
Bank infiltration (BI) is one of the solutions to providing raw water for public supply in tropical countries. This study in Malaysia explores the use of BI to supplement a polluted surface-water resource with groundwater. Three major factors were investigated: (1) contribution of surface water through BI to the resulting abstraction, (2) input of local groundwater, and (3) water-quality characteristics of the resulting water supply. A geophysical method was employed to define the subsurface geology and hydrogeology, and isotope techniques were performed to identify the source of groundwater recharge and the interaction between surface water and groundwater. The physicochemical and microbiological parameters of the local surface-water bodies and groundwater were analyzed before and during water abstraction. Extracted water revealed a 5–98 % decrease in turbidity, as well as reductions in HCO3 ?, Cl?, SO4 2?, NO3 ?, Ca2+, Al3+ and As concentrations compared with those of Langat River water. In addition, amounts of E. coli, total coliform and Giardia were significantly reduced (99.9 %). However, water samples from test wells during pumping showed high concentrations of Fe2+ and Mn2+. Pumping test results indicate that the two wells used in the study were able to sustain yields. 相似文献
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Sangeun Lee Suhaimi Abdul-Talib Heekyung Park 《Aquatic Sciences - Research Across Boundaries》2012,74(2):213-227
Numerous publications document increasing consensus in the scientific community that climate change will increase the severity
and frequency of drought. However, constructing large infrastructures is often viewed as an unreliable and inefficient option
in dealing with the problem of drought, owing to unpredictability of climate change. This study aims at illustratively presenting
that there is much room to improve drought management without resorting solely to infrastructure options. The adaptiveness
concept is first explained to examine the reasons of failure in drought management and appropriate options from the viewpoint
of a systems approach. Thereafter, a Korean water scarcity case is defined as the system dynamics model. The model is implemented
to include movement of water via the reservoir and water supply facilities, the operating rules of the reservoir, and the
relation between water scarcity and customer stress. Simulation results demonstrate that adaptiveness of drought management
was low because of untimely or limited options of the reservoir operator. They also show that most customer stress could be
largely mitigated by two options chosen from the adaptiveness concept. It is finally concluded that drought management needs
to be addressed with consideration of the adaptiveness concept before deciding solely on expansion of infrastructure upon
facing challenges due to climate change. 相似文献
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Mohd Khairul Nizar Shamsuddin Saim Suratman Mohamad Pauzi Zakaria Ahmad Zaharin Aris Wan Nor Azmin Sulaiman 《Environmental Earth Sciences》2014,72(8):3129-3142
Induced bank infiltration (BI) is commonly implemented in other countries, but remains new and unexplored in Malaysia. Increasing river pollution could affect drinking water resources. Given the threat of pollution to raw water sources, applying induced BI to sustain water management is essential. This paper presents a case study of the BI method, which evaluates the effects of groundwater pumping and BI operation on the installation of wells as well as determines the effect of pumping rate on flow paths, travel time, the size of the pumping and capture zone delineation, and groundwater mixing in a pumping well in Jenderam Hilir, Malaysia. The proposed method performs infiltration safely and achieves the ideal pumping rate. Numerical modeling packages, MODFLOW and MODPATH (particle tracking) were used. Results indicate that the migration of river water into the aquifer is generally slow and depends on the pumping rate and distance from well to the river. Most water arrives at the well by the end of a pumping period of 1–5 days at 3,072 m3/day for test wells DW1 and DW2, and during simultaneous pumping for DW2 and PW1 for a well located 36 and 18 m, respectively, from the river. During the 9.7-day pumping period, 33 % of the water pumped from the DW1 well was river water, and 38 % from DW2 throughout 4.6 days was river water. The models provide necessary information for water operators in the design and construction of pumping and sampling schedules of BI practices. 相似文献
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Suhaimi Suratman Keith Weston Naomi Greenwood David B. Sivyer David J. Pearce Tim Jickells 《Estuarine, Coastal and Shelf Science》2010
The aim of this study was to investigate the cycling of dissolved inorganic and organic nutrients using moored instrumented buoys (SmartBuoys) during the spring bloom in the North Sea. The instrumentation on the buoys enabled high frequency measurements of water-column integrated irradiance and in situ chlorophyll to be made, and also preserved water sample collection which were used for dissolved inorganic and organic nutrient analyses. The SmartBuoys were located in the year-round well-mixed plume zone associated with the River Thames and in the summer stratified central North Sea. These site locations allowed comparison of nutrient concentrations and cycling, and spring bloom development at two contrasting sites. The spring bloom was expected to be initiated at both stations due to increasing insolation and decreasing suspended load leading to higher water-column integrated irradiance. Due to differences in suspended load between the sites, the spring bloom started ∼2 months earlier in the central North Sea. The spring bloom in the Thames plume also resulted in higher maximum phytoplankton biomass due to the higher pre-bloom nutrient concentrations associated with riverine input. The use of SmartBuoys is also shown to allow the cycling of dissolved organic nutrients to be examined over the critical, and often undersampled, spring bloom period. Dissolved Organic Nitrogen (DON) clearly increased during the spring bloom in the central North Sea compared to winter concentrations. DON also increased in the Thames plume although showing greater winter variability related to higher riverine and sedimentary dissolved organic matter input at this shallow (∼18 m) coastal site. DON increase during the spring bloom was therefore related to primary production at both sites probably due to active release by phytoplankton. At both stations DON decreased to pre-bloom concentrations as the bloom declined suggesting the released DON was bioavailable and removed due to heterotrophic uptake and production. The preserved nutrient samples from the central North Sea site were also suitable for Dissolved Organic Phosphorus (DOP) analysis due to their low suspended load with similar trends and cycling to DON, albeit at lower concentrations. This suggested similar processes controlling both DON and DOP. The variable timing of short term events such as the spring bloom makes sampling away from coastal regions difficult without the use of autonomous technology. This study demonstrates for the first time the applicability of using preserved samples from automated buoys for the measurement of dissolved organic nutrients. 相似文献
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Tony Greer Ian Douglas Kawi Bidin Waidi Shun Jadda Suhaimi 《Singapore journal of tropical geography》1996,16(1):1-21
Resource development in the form of cyclical commercial logging activities results in a short period of often severe land disturbance followed by a prolonged phase of recovery. The monitoring of catchment sediment yield gives some indication of the gross erosion processes within the catchment as a result of the disturbance and may also effectively measure any ameliorative processes. Studies in Ulu Segama, Sabah, East Malaysia, recorded significant increases in stream suspended sediment loads as a result of logging. Stream loads were derived from a combination of daily sample measurements and storm event sampling using automated liquid samplers. Measured loads were then compared to computed loads from sediment discharge rating sets derived from the actual samples. Application of these ratings in the disturbed catchment initially underestimated sediment loads; however, a progressive overestimation of loads occurred as the catchment vegetation recovered. When using sediment rating curves as a tool to measure catchment erosion rates in disturbed environments, considerable caution has to be used. Vegetation recovery is reflected in the rapid recovery of stream water quality, making it necessary to continually review the rating. 相似文献
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