The influence of artificial vertical macropores in a compacted soil on the growth of winterwheat. II. Growth of winterwheat on a pseudogley

In a pseudogley the effect of artificial vertical macropores in a com- pacted structure was compared to a compacted structure without artificial vertical macropores and to a loosened structure. Only in a very wet year (830 mm precipitation). water extraction and yield were positively in- fluenced by the artificial vertical macropores in the compacted structure. Compared to the compacted structure without artificial macropores, where most of the water was extracted from the upper 25 cm of the soil, with vertical macropores most water was extracted from the depth 25-50 cm. In a dry year (700 mm precipitation), the difference in water exlrac- tion between the compacted structures with and without vertical macro- pores was only small. Most water was extracted from the loosened struc- ture, but yield was reduced compared to both compacted structures. How- ever, in the dry year, water extraction from the compacted S~NC~UIE with- out artificial macropores was uniform for the depth 0-50 cm, whereas for the structure with artificial macropores and for the loosened structure most water was extracted from the depth 0-25 cm. Neither in the wet nor in the dry year, vertical root extension was increased by the vertical macropores, but in the wet year root mass was positively influenced by the vertical macropores.