The anionic nature and high cation exchange capacity (CEC) of clinoptilolite zeolite can be exploited to reduce ammonia (NH3) loss from urea and to improve soil chemical properties to increase nutrient utilization efficiency in lowland rice cultivation. A closed-dynamic airflow system was used to determine NH3 loss from treatments (20, 40, and 60 g clinoptilolite zeolite pot−1). Seed germination study was conducted to evaluate the effects of clinoptilolite zeolite on rice seed germination. A pot study was conducted to determine the effects of clinoptilolite zeolite on rice plant growth variables, nutrient uptake, nutrient recovery, and soil chemical properties. Standard procedures were used to determine NH3 loss, rice plant height, number of leaves, number of tillers, dry matter production, nutrient uptake, nutrient recovery, and soil chemical properties. Application of clinoptilolite zeolite (15%) increased shoot elongation of seedlings and significantly reduced NH3 loss (up to 26% with 60 g zeolite pot−...

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Minimizing ammonia volatilization from urea, improving lowland rice (cv. MR219) seed germination, plant growth variables, nutrient uptake, and nutrient recovery using clinoptilolite zeolite

An overview of the basic engineering properties of Malaysian peats

The occurrence of severe floods in recent years globally as well as in many parts of Malaysia is an indication of both climate change and human interference in land use change. This requires for an integrated flood risk management approach and a shift from conventional structural flood mitigation. Flood modelling is an important part of flood risk management. In this study, development of one dimensional (1D) hydrodynamic model for Pahang River was performed in HEC-RAS 5.0 using combinations of surveyed data with spatial-extracted cross sections and recorded stream flow. The study area had been hit by several extreme floods that caused substantial property damages and loss of lives. This study focusses on the recent 2007 and 2014 flood events. Analyses of water levels, stream discharges and river cross sections were carried out based on the data gathered. A set of flood levels were obtained as the outputs of the hydraulic model and the accuracy of the simulated flood levels were validated. It was found that the model predicts a good output agreement with \(R^{2}\) = 0.96 and \(R^{2}\) = 0.82 for the 2007 and 2014 flood events respectively.

HEC-RAS One-Dimensional Hydrodynamic Modelling for Recent Major Flood Events in Pahang River

Malaysia as a country which received a very high rainfall throughout the year is moving towards adopting rainwater
harvesting system (RWHS) as a means to mitigate water shortage and flood problem. In 2012, RWHS is made
compulsory for every development of new housing and building at several states in Malaysia, both for water supply
and flood control. Furthermore, since flood is becoming more prevalent nowadays in Malaysia especially in
Kuantan, Pahang, lacks of space for the construction of flood mitigation facilities has prompted authorities to look
for other solutions for flood control. This study intends to determine the potential of rainwater harvesting site in
Kuantan, Pahang. Daily rainfall data from six selected hydrology stations in Kuantan catchment are used to analyse
the water availability in order to identify the potential of rainwater harvesting site in Kuantan. The highest amount of
rainfall received by all stations for five consecutive years is on December except for two stations recorded highest
amount of rainfall on January in year 2011 and three stations recorded highest amount of rainfall on February and
May in year 2013. Meanwhile the least number of rainfalls received by all stations for five consecutive years varies.

Rainfall Analysis to Determine the Potential of RainwaterHarvesting Site in Kuantan, Pahang

Flood catastrophe that struck Kelantan in 2014 has marked as the worst in history. The absence of structural approach such as dam has increased the risks of the flood to this state. In this paper, the simulation of 2014 flood event focuses in Kuala Krai area has been carried out before and after the occurrence of the proposed dams along Galas and Lebir rivers, respectively using hydrodynamic model. The Digital Terrain Model (DTM) from Airborne Light Detection and Ranging (LiDAR) combining with Shuttle Radar Topography Mission (SRTM) data resources have been used for hydrodynamic modelling. The flow hydrograph and water level are generated as input data for initial and boundary conditions. River crosssections and Manning’s roughness coefficient values that been estimated based on landcover map obtained in 2010 also used in the model. The model produces the outputs of flood depth and velocity. To validate the simulation results, the flood depths were compared against the flood marks depth from field survey at 16 locations collected by researchers from Disaster Prevention Research Institute, Kyoto University, Japan and Department of Irrigation and Drainage (DID). From the validation, it reveals that the average accuracy percentage obtained was about 90% and it can be said that the flood model was acceptable.

The validation of hydrodynamic modelling for 2014 flood in Kuala Krai, Kelantan

Statistical analysis of annual rainfall patterns in peninsular malaysia using TRMM algorithm

A massive flood event, which hit Kelantan in 2014, has contributed a major destruction particularly at Kuala Krai district An alternative approach to overcome this flood episode is by constructing dams In this study, two dams proposed at the upstream of Galas and Lebir river, near Kuala Krai This paper aims to assess the implementation of the proposed dams which is a structural approach at the upstream area to reduce flood hazard in Kelantan using a hydrodynamic model A coupled of 1D and 2D hydrodynamic model have been tested to simulate the occurrence of flood events in Kelantan due to the proposed dams The Digital Terrain Model (DTM) has been generated by combining the data sources; ie from Airborne LiDAR and SRTM The design of proposed dams were defined based on 50 years flood characteristics proposed by UPEN and simulated into the DTM with different magnitudes of flood The flow hydrograph and water level for 25, 100 and 200-year return period are generated as input data for initial and boundary conditions River cross-sections and hydrodynamic roughness value of Kelantan catchment area are also used in the model The flood that has been observed is focused on Kuala Krai area before and after the construction of the proposed dams The results of maximum velocity and water depth from the hydrodynamic modelling results are then generated to produce flood impulse and flood hazard maps The results obtained from the preliminary study of the hydrodynamic modelling at Kuala Krai after the development of the proposed dams showed that no flood occurred at the downstream based on the streamflow input consideration

Hydrodynamic modelling of a proposed lebir and galas dam for flood hazard analysis

Remote Sensing (RS) data and Geographical Information System (GIS) play a rapidly increasing role in the field of hydrology and water resource development. The ability of RS to generate information in spatial and temporal domain can be consider as one of its greatest advantages in providing data for hydrological modeling and monitoring. This is very important since the availability of such information is very crucial for successful model analysis, prediction and validation. The use of RS technology will involves large amount of spatial management and thus requires an efficient system to handle such data. The GIS technology provides suitable alternatives for efficient management of large and complex databases. This study attempts to quantify the water balance components of the Bekok Reservoir in the state of Johor, Malaysia. This will enable us to determine the major factors that contribute to the input and output of water into the reservoir. An assessment will also be made to find out the hydrological responses due to land use and land cover change. Meteorological data such as rainfall and evapotranspiration are the main input data for the calculation of water balance. Spatial rainfall data will be obtained from Tropical Rain Measuring Mission (TRMM 2A25), while evaporatranspiration will be derived from ASTER satellite data using HBV-96 run-off model.

Tam Tze Huey

Papers

Statistical analysis of annual rainfall patterns in peninsular malaysia using TRMM algorithm

Hydrodynamic modelling of a proposed lebir and galas dam for flood hazard analysis

Application of remote sensing and geographical information system (GIS) for reservoir water balance analysis

Remote sensing methods for mapping flood-prone areas

Integration of biometric and remote sensing techniques for estimation of net ecosytem productivity in tropical rain forest