Soil Profiles: Kuantan
Kuantan Series
The Kuantan Series is a member of the Kuantan Family which is a very fine, oxidic, isohyperthermic, brown Tipik Akrolemoks. It typifies this family and is developed over basalt. These are deep (> 100 cm), very friable and uniformly brown soils having a thin dark brown to brown A horizons and dark yellowish brown clayey B oxic horizons. The depth of these soils often exceeds two metres below which iron-coated basalt parent material occurs. The ECEC values are less than 1.5 cmol (+) kg–1 clay in the oxic horizon.
Type Location
The Kuantan Series was first established by Owen (1951) in the vicinity of Kuantan town. The above pedon was described by Paramananthan (1977) at the Bukit Goh Felda Oil Palm Scheme, near Kuantan, Pahang. The elevation was 30 metres (100 ft) and on midslope of a short (8% or 4°) slope in gently undulating terrain. Location: Topographic Sheet 4360, 3°55′ N, 103°15’40” E (Grid reference 4360 – 855325 m).
Range in Characteristics
The range in characteristics of the Kuantan Series has been outlined by Paramananthan and Lim (1974). The A horizon is often a thin dark brown (10YR4/3) clay while the B horizons which are uniform and deep have colours ranging from dark yellowish brown to dark brown through to reddish brown (10YR4/4, 7.5YR4/4 and 5YR4/4) with clay textures. The structures are generally very weak subangular blocky breaking readily to strong granules. The soils have extremely friable consistence and clayballs are often found in the profile. Drainage is somewhat excessive. The profiles are usually very deep and almost always exceed two metres in depth. Below this depth the soil changes abruptly to yellowish red iron coated parent material. Sometimes a band of loosely packed petroplinthite gravels occur at depth above the basalt.
Competing Soils and Their Differences
The Kuantan Series is at an advanced stage of weathering and therefore tends to resemble other soils at a similar stage. The soils which are fairly similar include Sungei Mas Series and Senai Series. The Sungei Mas Series is fairly similar to the Kuantan Series. The Kuantan Series in general has much yellower hues than the Sungei Mas Series. The Kuantan Series is derived from basic lavas (or tuffs) while the Sungei Mas Series on serpentinite. Occasionally the Kuantan Series (on steeper slopes) develops yellowish red colours. The Senai Series has higher values and chromas and is developed over gabbro parent material. The Tangga Series described by Lim (1976) belongs to the same family but is developed over limestone. The Table Series mapped in Sabah over basalts has a morphology similar to that of the Kuantan Series but generally has higher cation exchange capacity values. The Pinianakan Series mapped in Sabah over serpentinites has dusky red colours and higher cation exchange capacity values. The Goh Series mapped locally in the Jabor Valley area in Pahang is the moderately deep (50– 100 cm) equivalent of the Kuantan Series.
Setting
The Kuantan Series typically occurs on gently undulating terrain (4–20% or 2– 10° slopes) over the Quaternary basalts (1.6 My) in the vicinity of Kuantan. They occur at elevations not exceeding 150 metres (450 ft).
Principal Associated Soils
In the Kuantan area, where these soils have only been mapped to-date, they occur as distinctive soils easily distinguished from other soils such as Rengam Series, Bungor Series etc. in the surrounding area. Therefore they have only been mapped as a single series and never in association. In detailed mapping the Kuantan Series is locally associated with its moderately deep equivalent the Goh Series and the shallow equivalent the Jabor Series.
Drainage and Permeability
The soils of the Kuantan Series have very rapid permeability and very rapid internal drainage. They are somewhat excessively drained soils.
Use and Vegetation
Except for a small area in the Bukit Goh Forest Reserve which is under Lowland Dipterocarp Forest most of the areas under the Kuantan Series have been developed for agriculture. The common crops are fruit trees, rubber, and oil palm which are mainly under estate management and some under smallholders.
Distribution and Extent
The Kuantan Series has only been mapped in the vicinity of Kuantan town in Pahang. They are estimated to occupy about 18,000 ha. They are found in the Bukit Goh Forest Reserve, Bukit Goh Felda Schemes and in Jabor Valley and a little in southern Terengganu.
Series Established
This soil was established near Kuantan, Pahang by Owen (1951). The source of name is Kuantan town in Pahang, Peninsular Malaysia.
Remarks on Classification
The Kuantan Series is classified here according to the Malaysian Soil Taxonomy – Second Approximation (Paramananthan 1998) as a member of the very fine, oxidic, isohyperthermic, brown family of Tipik Akrolemoks which is developed over basalts. They are classified here as soils having a deep oxic horizon, heavy clay texture, weak structures and a low (< 1.5 cmol (+) kg–1 clay) cation retention capacity in the B horizon. In the Keys to Soil Taxonomy – Eighth Edition (Soil Survey Staff 1998) these soils would be classified as Typic Hapludox as they do not meet the pH requirement of the Acrudox. In the FAO/UNESCO Soil Map of the World – Revised Legend (FAO 1990) the Kuantan Series would probably be classified as Geric Ferralsols.
Suitability for Agriculture
The somewhat excessive drainage can be a serious limitation to the agricultural potential of the soil. Oil palm yields can be expected to fluctuate significantly with periods of drought. Moisture, P fixation and low nutrient content are expected to be the major limitations of this soil. The establishment of the cover crops and the main crops is difficult particularly if droughts are encountered. Once established, rooting is deep and moisture is not expected to be that serious a problem.
