摘要
Highly weathered soils are distributed in the humid and wet-dry tropics, as well as in the humid subtropics. As a result of strong weathering, these soils are characterized by low activity clays, which develop variable surface charge and related specific properties. Surface reactions regarding base exchange and soil acidification, heavy metal sorption and mobility, and phosphorus sorption and availability of the tropical highly weathered soils are reviewed in this paper.Factors controlling surface reactivity towards cations and anions, including ion exchange and specific adsorption processes, are discussed with consideration on practical implications for rational management of these soils. Organic matter content and pH value are major basic factors that should be controlled through appropriate agricultural practices, in order to optimise favorable effects of colloid surface properties on soil fertility and environmental quality.
Highly weathered soils are distributed in the humid and wet-dry tropics, aswell as in the humid subtropics. As a result of strong weathering, these soils are characterized bylow activity clays, which develop variable surface charge and related specific properties. Surfacereactions regarding base exchange and soil acidification, heavy metal sorption and mobility, andphosphorus sorption and availability of the tropical highly weathered soils are reviewed in thispaper. Factors controlling surface reactivity towards cations and anions, including ion exchange andspecific adsorption processes, are discussed with consideration on practical implications forrational management of these soils. Organic matter content and pH value are major basic factorsthatshould be controlled through appropriate agricultural practices, in order to optimise favorableeffects of colloid surface properties on soil fertility and environmental quality.
关键词
重金属
高度风化土壤
热带土质处理
可变电荷矿石
heavy metal
highly weathered soils
phosphorus
tropical soil management
variable charge minerals