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In this study, an alternative approach was applied for the characterization of the subsurface geological conditions to estimate the hydrological parameters in the absence of subsurface soil data. The study revealed that the hydrological parameters, estimated from the Transient Electromagnetic (TEM) and Electrical Resistivity Tomography (ERT), were significantly correlated with in situ data. Overall estimated infiltration rate (below 20 inches/h) predicted fine-grained soil was also associated with in situ data. A high correlation among the bulk electrical resistivity, porosity, and the resistivity of the pore fluid thereby confirmed the relevance of Archie's law used in this study. Furthermore, results showed that both TEM and ERT are vital tools for hydrological parameter estimation. [ABSTRACT FROM AUTHOR]

The present study is carried-out to have an idea about varying infiltration rates with varying soil types and cover in Kota Bharu- the capital of Kelantan state. The study area, covering a land area of about 394 km? lies between latitudes of 06°10'N and longitude of 102°20'E. Geologically, the area is mainly comprised of Quarternary alluvium having fluvial and marine origin which is constituted of mainly sand, gravel, silt and clay underlain by granite and metasedimentary rocks. The soil properties like texture, structure, water content, temperature and other factors like vegetation types and cover, and rainfall intensity play a significant role in controlling infiltration rate. Generally, coarse grained soils having large pore spaces with stable structure allows water from rainfall to enter unimpeded throughout a rainfall event. Otherwise, soils that have reduced infiltration may cause flooding in the area. From the soil classification map produced by Department of Agriculture (DOA), selected soils would be tested using double ring method to identify the infiltration rate in the study area. The method employed consists of two metal cylinders of diameter 30 cm and 60 cm that are driven partially into the soil. The ring is filled with specific level of water and the time at which water moves into the soil is measured, thus the rate of infiltration could be calculated in the field. An infiltration map will be produced at the end of the study which will be very useful for decision makers while dealing with flood management. The present study will be also very handy in agricultural field regarding the judicious and timely irrigation. [ABSTRACT FROM AUTHOR]