Mineral substances in natural grassland under different nitrogen fertilizing systems
1997
Jancovic, J. (Slovak Agricultural Univ., Nitra (Slovak Republic))
Over eight years (1986-1993) on a Cynosuretum type of semi-natural grassland floristic changes that simplified grassland community occurred. By the alternation of PK and NPK fertilization the legume species vitality increased. In dry matter crops the alternating intensity of fertilization accords with the yearly N-fertilization application. The P content in dry matter did not achieve the optimal parameters for farm animal requirements with respect to unsuitable soil properties and insufficient grassland reaction upon the chosen fertilization systems. By alternating fertilization intensity the K in dry matter was accumulated for a required need (27.74 - 22.84 g per kg) and in a dose of 240 kg per ha the K content decreased to the level of a controlled variant. With the increasing intensity of N-fertilization the Ca content in dry matter decreases but its content usually increases by this alteration with P-K fertilization. The Ca concentration was highest on a non-fertilized control and P-K variant. The Mg content in dry matter did not decrease to under 2.50 g per kg in both fertilization systems except in the P-K variant. The Mg content was increased with a dose of N
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