Nutritive status of soils, botanical composition and yielding ability of grasslands in conventional and organic farm
2002
Geherman, V. (Academical Agricultural Society, Tartu (Estonia))
The general purpose was to study the productivity of organic grasslands and compare this with productivity in the same or similar climatic and pedologic conditions situated conventional farm. The investigation based on field experiments that were carried out in 4 different regions of Estonia. In current research work the botanical composition, the DM-yield of sward, soil pH sub(KCl), and content of organic matter on the 4 research plots of 5 square m were measured. The content of soluble plant nutrients (P, K,and Mg, Ca) estimated by AL (ammonium acetate extraction) method. The dominant soil types in farms of West-Estonia were Calcic Cambisols and in North-Estonian farms Calcic Gleysols, in South-East Haplic Podzols types prevailed. The content of organic matter was higher in organic farms, pH and soil types were the same in compared farm pairs. The content of lactate soluble P and K depended mostly on the location of farms. The low content of P and K in soil was caused by the low content of parent material in soil and also by very low fertilising level used in conventional farm. One of the most important aim in the Estonian grassland husbandry is the use of legume plants as the source of nitrogen and for increase the protein content of forage. Botanical composition of sward did not differ between conventional and organic farms. The average DM yield of the grasslands in the first cut and the total DM yield were by 10-20 per cent higher in conventional farms. The results did not show a large differences between two farm types, because conventional farms with legume-rich grasslands were quite similar to organic farms which used grass-legume mixtures and few mineral fertilisers
显示更多 [+] 显示较少 [-]