Preferential Leaching of Water and Chloride in a Clay Loam Soil as Affected by Tillage and Rainfall Intensity

摘要

There is a concern that preferential flow (i.e. bypass of soil matrix) of water and chemcials through soil macropores may enhance leaching below the root zone of agricultural crops, which may impact groundwater quality. Our objective was to investigate the nature of predferential folw in a clay loam soil and to ascertain the potential impact of tillage tillage (heavy-duty cultivator) and no-till field located at Lethbridge in southern Alberta. Four large (46×46×51 cm) undisturbed soil blocks were excavated from each tillage field (unreplicated)during the fallow phase of a wheat-fallow roration. The soil blocks were transported to the laboratory, stored under drying conditions (32 months), and rainfall-leaching experiments conducted under unsaturated, transient conditions.