Short Communication: Agroforestry as sustainable agroecosystem in terrestrial semi-arid region, Indonesia: Evidence from soil organic carbon

Abstract. Moata MRS, Takalapeta AM. 2021. Short Communication: Agroforestry as sustainable agroecosystem in terrestrial semi-arid region, Indonesia: Evidence from soil organic carbon. Intl J Trop Drylands 5: 1-4. Agroforestry system has been recognized as a better system for food security, especially during dry season in a tropical region. Therefore, the sustainability of this system becomes crucial for rural livelihood, especially in dryland areas. One indicator for sustainable agriculture system is the total amount and quality of the soil organic matter (SOM) which is expressed as soil organic carbon (C-org). Therefore, this study focused on soil quality of three land uses (forest, dryland agriculture with less input, and agroforestry) under Inceptisol, Entisol, and Alfisol from 36 locations at dryland terrestrial ecosystem in West Timor-Indonesia. The results showed that all soils are dominated by clay and silt loam textures (54%) and neutral pH (83%) but still have very low SOM and C-org < 1% (48%). However, a mixed cropping system (agroforestry) provides a higher C-org compound (5% C-org) than other land uses (< 1% C-org). Carbon has a strong correlation with nitrogen (r=0.90, p= 0.0004), weak correlation with potassium (r= 0.51, p= 0,13) and correlation with phosphorus-P (r= 0.30, p = 0.40). The SOM in these terrestrial ecosystems has a moderate correlation with Cation Exchange Capacity (CEC) (r= 0,64, p = 0.04). It is indicated that most of the soil nutrients and CEC were influenced by SOM (C-org) except P (likely from mineral soil). It is a promising finding that agroforestry is a sustainable system for agriculture where SOM could be key driver for land productivity in the terrestrial ecosystem.