EFFECTS OF SOIL COMPACTION ON DEVELOPMENT AND NUTRIENT-UPTAKE OF PEAS

During a rainy period in 1990, most pea fields in an area in southwestern Sweden developed a patchy, premature yellowing and wilting in a pattern pointing out machinery-induced soil compaction as a major reason. A sampling investigation was conducted in 11 fields, and in each of these a plot with green peas (G) was compared with an adjacent plot with yellowing peas (Y). In Y the soil was much harder than in G. The air-filled porosity in the plough layer at a matric water tension of 100 hPa was reduced from 13.1 to 8.6% (v/v), which led to insufficient soil aeration, to poorer Rhizobium-nodulation and reduced N content in the shoots, and to reduced uptake of other plant nutrients.