Optimisation of morphometric parameters of Limbang river basin, Borneo in the equatorial tropics for terrain characterisation

Abstract

Limbang River basin (LRB) in the equatorial tropics was characterised through the statistical optimisation of morphometric parameters of its 33 subwatersehds of various orders. Basic, linear, aerial and relief parameters which are capable of expressing the geological, structural and relief setup of the river basin were estimated. The present study will enhance the scientific understanding about geomorphometric setup of the Limbang river basin, since there is no previous information is available. The 8th order river basin shows spatial variation in estimated parameters suggest the differential influence of lithological, structural and relief characteristics over the present geomorphological condition of the river basin. Overall, the results of morphometric parameters analysed reveal that the area is geologically complex and poses high runoff, low permeability and infiltration along with high rate of erosion and flash flood proneness. Among the estimated variables few of them shows statistically significant interdependency (r ≥ ± 0.80). Spatial variation in morphometric characteristics facilitated the categorisation of river basin into different zones having varying structural complexity, runoff potential and erosion proneness. The findings of the present study will aid in planning further hydrological development activities in the river basin.