Assessment of seawater intrusion to the agricultural sustainability at the coastal area of Carey Island, Selangor, Malaysia

Abstract

Groundwater suitability for agriculture in an island with limited recharge area may easily be intluenced by seawater intrusion. The aim of this study was to investigate seawater intrusion to the suitability of the groundwater for oil palm cultivation at the ex-promontory land of Carey Island in Malaysia. This is the first study that used the integrated method of geo-electrical resistivity and hydrogeochemical methods to investigate seawater intrusion to the suitability of groundwater for oil palm cultivation at two different land cover condition. The relationship between earth resistivity, total dissolved solids and earth conductivity was derived with crop suitability classification according to salinity, used to identify water types and also oil palm tolerance to salinity. Results from the contour conductivity maps show that area facing severe coastal erosion and area still intact with mangrove forest exhibits unsuitable groundwater condition for oil palm at the unconfined aquifer thickness of 15 and 3 1 m, respectively. Based on local sea-level rise prediction and Ghyben-Herzherg assumption (sharp interface), the condition in the study area, especially in severe erosion area, by the twenty-first century will no longer be suitable for oil palm plantation. The application of geo-elechcal method combined with geochemical data, aided with the information on environmental history and oil palm physiography, has demonstrated that the integration of techniques is an effective tool in defining the status of agricultural suitability affected by salinity at the coastal aquifer area.

Correlation Analysis Between Field Electrical Resistivity Value (ERV) and Basic Geotechnical Properties (BGP)

“…In addition to the user friendliness of the software, RES2DINV is adopted worldwide as a resistivity data processing tool. Its use has been cited by many researchers involved in resistivity tomography studies [9][10][11][12]. The software is supplied by Geotomo Software Company in Penang, Malaysia.…”

The Use of Electrical Resistivity Method to Mapping The Migration of Heavy Metals by Electrokinetic

“…The groundwater samples, the anion analysis was chloride (Cl-), sulphate (SO42-), nitrate (NO3-) and bromide(Br-), on Dionex ion chromatography model ICS2000. While, the cation analysis were sodium (Na), calcium (Ca), magnesium (Mg), potassium (K) and iron (Fe), on Perkin Elmer inductive coupled plasma optical emission spectrometer model Optima 3300RL [24] This study was performed using ABEM Terrameter LS with configuration based on Schlumberger array and Wenner array. The survey used four resistivity land cables, 61 electrodes and 64 jumper cables with 5.0 m spacing along 200 m length.…”

Integrated geophysical image of the hot spring in Rokan Hulu, Riau, Indonesia

“…Islami et al (2018a) investigated the presence of potential groundwater in peat area using one-dimensional geoelectrical resistivity. Geoelectrical two-dimensional resistivity method has also been successfully used in the case of seawater intrusion in an aquifer and delineation of leachate plumes (Khaki et al, 2016;Baharuddin et al, 2013;Zeinab et al, 2012;Samsudin et al, 2007). The method also has been successfully used for time-lapse nitrate monitoring in shallow groundwater system and also in the investigation of the possibility of heavy metal in the aquifer system (Islami et al, 2012;Islami, 2017;Islami et al, 2018b).…”