Effect of tillage on water economics in soil profile and on maize yields
2000
Zubec, F. | Jambor, P.
At the vegetation period beginning relative good water supplies were registered at all treatments. In 0.9 m soil profile was totally 218-242 mm, i.e. approximately 73% of maximum capillary water capacity volume. Among the treatments were observed only small differences. Higher water supplies were in the variants more compacted. Smaller supplies were in the variants with ploughing and subsoiling. Extremely dry and hot weather in spring and summer months resulted in intensive and deep soil profile drying. Largest water supply decrease was observed at variants with ploughing and subsoiling, where already in the June end were soil supplies reduced in monitored profile (0.0 - 0.9 m) to the values near to wilting point (137 and 151 mm). While at the variants without subsoiling soil water supplies in the same depth were 166 - 210 mm. Heavier precipitation in July second part improved soil water balance only for shorter period. More beneficial reaction was observed at the treatments with subsoiling than treatments without subsoil loosening. In spite of this already in following month - August waters supplies in soil profile in all variants (with exception of control - Oa, Ob) decreased to the level of wilting point or even deeper (93 - 132 mm). Precipitation in September increased water supplies in soil profile practically without any effect on yields. Higher water consumption took place at the variants with subsoiling, both with or without ploughing. More intensive evapotranspiration corresponded with highest yieds - 5.33; 7.01 t.ha-1, i.e. 50.1 and 98.1% while in the other variants yield increase was registred in range 3.59 t.ha-1 i.e. + 1.7% (no-till) up to 5.00 t.ha-1, i.e. + 41.6%. Soil water economy was most supported by subsoiling (both 0.4 and 0.6 m) and contour tillage. The same was valid at yields heights
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