Comparative Ecological Characteristics and Return in Smallholding Rubber-Based Monoculture and Agroforestry in Nam Noi Sub-district, Hat Yai District, Songkhla Province

Abstract

The research was carried out in Nam Noi Sub-district, Had Yai District, Songkhla Province, in a 21 year old rubber plantation. The objective was to compare the ecological characteristics and economic return of rubber-based monoculture and agroforestry. Inventory plots were laid out to assess ecological characteristics and questionnaires and interview were used to assess the return by using economic value such Net Present Value (NPV) and Internal Rate of Return (IRR).

The results showed that rubber-based agroforestry has more diversity based on the ecological characteristics. Specifically, the monoculture had three canopy layers with four stem size classes, while the agroforestry had four canopy layers. The total biomass of the monoculture and the agroforestry were 22.30 and 45 tonne per rai, respectively. For the 21 years period, the financial inputs of the two systems were 157,426.48 and 166,492.68 baht per rai, the incomes were 273,508.20 and 339,747.96 baht per rai, NPV (at 7 % interest rate) values were 32,455.44 and 51,978.53 baht per rai, and IRR value were 21.0 and 23.45 %, respectively.