Nutrients Leached under Lychee Cultivation of an amended Northern Thai Highland Acrisol

摘要

Lychee cultivation in northern Thailand is a popular method to earn income for farmers. Fertilizer and soil amendments will always be recommend for improving soil properties. This experiment examines responses of selected soil amendments and NPK fertilizer on nutrients leached under lychee canopies of an Acrisol soil. An experiment was conducted with resin buried at 30 and 60 cm depth for 4 months. Chemical application cause more leaching of nutrients than other treatments. The amount of elements absorbed by resin at 30 cm. was large compared with 60 cm depth for all extractants. The contents of nutrients extracted by 0.5N HC1 gave lower values than BrayII and NH4OA_c pH 7.0. The amounts of nutrients leached were at low levels for fly ash application. In addition, extractable S at 60 cm depth ranged from 73 to 133 mg/kg being higher than the amount of S at 60 cm depth of 54 to 86 mg/kg. The treatments resulted in various leaching conditions under lychee canopies for the Acrisol soil. More nutrientsand heavy metals including trace elements should be analyzed.