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Short-term changes in tropical rainforest soil properties and their impact on C cycling following land-use conversion to agriculture have received intensive study. However, long-term, land-use changes have not been explored for tropical Andisols, whose high carbon stocks and several distinctive properties may differ in their response to land-use conversion. Thus, the primary objective of this study was to assess changes in selected soil properties of Andisols in response to long-term (>100 years) changes of land use from tropical rainforests to agriculture. Soils were sampled by horizon to a depth of 110–140 cm in pine forests (PF), tea plantation (TP) and horticultural crops with either intensive cultivation (IH) or bare fallow (FH) cropping systems. Selected physical, chemical and biological soil properties were characterized, including microbial biomass carbon (MBC) and laboratory CO2 mineralization rates. Results showed that land-use change from rainforest to agriculture resulted in increased soil bulk density and meso/micropores that contributed to increased plant-available water retention capacity. Soil carbon and nitrogen stocks in the upper 1 m of soil were higher in agricultural soils (25–29 kg C m−2; 1.7 – 2.3 kg N m−2) than pine forest soil (17 kg C m−2; 1 kg N m−2) with a redistribution of organic matter from topsoil to subsoil horizons. Organic matter quality was also affected by land-use conversion with the horticultural soils having lower rates of carbon mineralization per unit soil carbon (PF > TP > IH > FH) and lower microbial biomass, especially in topsoil horizons. The MBC sharply decreased in the topsoil horizon due to land-use change from forest (330 mg kg−1) to agricultural production (

This study aimed to identify the characteristics of Andisols under tea plantations affected by different Oldeman's agro-climatic zones, of different ages, and containing different types of volcanic ash material. For this study, three tea plantation estates were chosen, the Ciater Site (CTR), Sinumbra Site (SNR), and Sedep Site (SDP), having Oldeman's agro-climatic zones of A, B1, and B2, respectively. Three profiles (CTR-A, CTR-B, and SNR-A) were created from andesitic volcanic ash, and three profiles (SNR-B, SDP-A, and SDP-B) were created from basaltic volcanic ash materials. The CTR-A, SNR-B, and SDP-B profiles were obtained from Holocene parent materials, while the CTR-B, SNR-A, and SDP-A profiles were derived from Pleistocene parent materials. Soil samples were taken from the soil profiles from depths of 0 to 153 cm incrementally, dependent on each soil horizon thickness. The findings of the study reveal that the age of parent materials and the variance in agro-climatic zones result in considerable differences in soil chemical characteristics, such as pH (H2O), base saturation (BS), and organic C, while the qualities of the basaltic and andesitic volcanic ash parent materials were also shown to be unaffected. All Andisol profiles went through cambic weathering processes. Moreover, the key pedogenetic strategies were the production of short-range-order minerals through the leaching of easily dissolved elements and the coprecipitation of SiO2 and Al2O3 gels. Halloysite was formed by the resilication of short-range-order minerals, while gibbsite was formed by desilication. The XRD analysis indicated that amorphous materials predominated with some HIV and kaolinite minerals were also present. [ABSTRACT FROM AUTHOR]