Title: Examining the uneven growth rates of rubber trees: the case study at a plantation in North-Eastern Thailand
Authors: Jit Ping Siew; Siok Kun Sek
Addresses: School of Mathematical Sciences, Universiti Sains Malaysia, 11800 Minden, Penang, Malaysia ' School of Mathematical Sciences, Universiti Sains Malaysia, 11800 Minden, Penang, Malaysia
Abstract: This study seeks to empirically identify significant factors that contribute to the uneven growth rates of rubber trees using statistical analysis of collected data. The uneven growth rate of rubber trees has caused to the variation in maturity of rubber trees which may then affect the economic returns of the rubber estate. The revealing of the factors may help to reduce the uneven growth rate and the losses caused by this problem. Applying the Tobit model analysis, the results reveal that the land slope and forest boundaries are significant primary factors in influencing the growth rate of rubber trees. Exhibiting the results in three dimensional plots shows that topsoil erosion leads to soil accumulation at foothills of land slopes and this can inhibit growth. On the other hand, ground water table height does not affect the growth rate significantly.
Keywords: rubber tree growth; Tobit model; censored regression; Thailand; growth rates; rubber trees; case study; rubber plantations; land slope; forest boundaries; topsoil erosion; soil accumulation; groundwater table.
International Journal of Agricultural Resources, Governance and Ecology, 2015 Vol.11 No.3/4, pp.387 - 405
Available online: 07 Jan 2016 *Full-text access for editors Access for subscribers Purchase this article Comment on this article