Effect of 50-year term different crop rotations on soil organic matter

Soil carbon sequestration is almost only negative emission technologies which are readily available at a low cost and crop rotation is one of those. Identification and implementation of land use and soil management practices which create a positive agricultural soil organic matter and restore soil quality is specific challenge worldwide. Long-term field experiment was established in 1966 at the Experimental Station of Vytautas Magnus University. 9 different crop rotations were arranged in time and space. In addition, Continuous rye monoculture (with and without herbicides and mineral fertilizers) as well as Continuous bare fallow were included as control treatments. Investigations were carried out in 2015 and 2018 (after 50-year term). Soil – Calc(ar)i-Endohypogleyic Luvisol. The objective of this investigation was to compare the effect of different crop rotations and rye monoculture as well as 50-year bare fallow on soil organic matter. The highest soil organic matter (SOM) content established in crop rotations with perennial grasses and/or with farmyard manure application: Cereal, Norfolk, Fodder and Field with raw crops. Crop rotations For green manure and Intensive, in which soil productivity supported with green manure, indicated lower SOM. The least SOM content was in Cereal and Three course crop rotations. SOM stocks were 16.9 % and 22.5 % lower to compare with Norfolk crop rotation. SOM in Continuous bare fallow obtained 2 times less. Bare fallow without farmyard manure application mostly decreased soil productivity. Crop rotation design in modern agriculture persist as one of major instruments for soil organic carbon management and sustainable intensificationAgronomijos fakultetasVytauto Didžiojo universiteta