Effects of plant growth on the dynamics of the soil solution composition in the root zone of maize in four Japanese soils

Abstract

Abstract The effects of plant growth on the dynamics of the chemical composition of the soil solution were studied by growing maize (Zea mays L.) in four Japanese soils. A pot experiment was carried out with eight treatments: four soil materials with and without plants. In each pot^four samplers with a looped hollow fiber (LHF-samplers, Yanai et al. 1993: Soil Sci. Plant Nutr., 39, 737-743) were installed and the soil solutions were sampled nondestructively from the root zone in situ, five times during the 50-day growth period. In soils supporting active plant growth, electrical conductivity and concentrations of Ca, Mg, K, and NO3 in the soil solution decreased and the pH increased significantly with plant growth. Spatial differences were also observed: soil solutions in the upper parts of the pots were significantly less concentrated in some elements than those in the lower parts. As in the case of concentrations, the composition of the soil solution was also affected by plant growth: the activity ratio...