Rubber agroforestry system (RAS) practices to overcome rubber price and soil erosion in Southern Thailand

Abstract

Most of rubber agroforestry system (RAS) showed strategies to reduce the chemical methods. The economic margins of the 5 plots for 6-year simulation (2019-2024) were divided into 3 levels; high, medium, and low level of ability to overcome the low rubber price. Plot 1, 2 and 4 were high levels because stingless bee and bamboo in plot 1, sala in plot 2, and champadak and phakleang in plot 4 which provided more products, and the price of products were high. Especially, all these 3 plots had not spent much cost in the plots. Plot 5 was a medium level, plot 3 was low level. However, eaglewood trees in plot 3 provided very high income when age was proper for harvesting but beyond the 7-year simulation. Coffee trees in plot 5 would increase the products every year. All RAS plot practices are still an alternative to improve the livelihood of RAS farmer households. On the other hand, the plant community structure is composed of rubber trees with upper canopies and intercrops with lower canopies. When the rain come, all canopies are intercepted by absorbing the raindrops until saturated. So, the rest of raindrops would be stemflow and throughfall to the lower canopies and ground which covered by leaves and branches of rubbers and other intercrops that were fallen and decayed. These layers helped to prevent soil erosion caused by rainfall. The crown covers of all plants’ canopies in representative areas of all 5 RAS plots ranged from 93 to 98% of area that provided a great potential to protect soil from direct rainfalls in raining season and had ability to keep moisture in the plots due to the multiple levels of vertical stratification and crown covers