Soil properties and phosphorus sorption characteristics due to land use change from pepper-based agroforestry to cassava in North Lampung, Indonesia

Abstract

Changing pepper-based agroforestry land to cassava is massively conducted by farmers in North Lampung, Indonesia because the pepper price is low. This research was aimed to reveal the changes in the chemical properties and the characteristics of P sorption in the North Lampung regency because of the change in land use from pepper-based agroforestry to cassava. Soil pH, exchangeable aluminum (Al), organic carbon (C), basic cations, cation exchange capacity (CEC), and P sorption-desorption were analyzed in collected soil samples. The results showed that soil properties and P sorption-desorption characteristics changed. The land cultivated with cassava for fifteen years had lower pH, organic C, basic cations, CEC, and higher exchangeable Al than land cultivated with pepper-based agroforestry. In topsoil, the P sorption maximum, P binding energy, and standard P requirement of fifteen years old cassava land were higher than those of pepper-based agroforestry. Organic C negatively correlated with the P binding energies. The results revealed that land use change from pepper-based agroforestry to cassava had an adverse effect, on soil organic C and tended to increase P sorption maximum, P binding energy, and standard P requirement. Organic matter management was necessary to maintain soil organic carbon in sufficient status.