The impact of rotational grazing on biomass characteristics in boreal alluvial meadows

Northern Boreal alluvial meadows are semi-natural habitats that require extensive management. They also have lower productivity as compared to cultivated grasslands. The subsidies for keeping meadow habitats open are currently activity-based, not results-based, and farmers tend to keep stocking rates low. This is not sufficient to keep meadows in good condition. We studied the impact of rotational grazing on biomass yield and forage quality in Estonian semi-natural alluvial meadows. Two traditionally extensively grazed pastures of approximately 36 and 20 hectares were divided into rotational systems, one of which consisted of four paddocks and the other of which consisted of eight paddocks. Other parts of the same grassland were used for low-load extensive grazing and control areas. Biomass samples we collected to measure both quantitative and qualitative parameters. We revealed that, with paddocks and rotating animals, the overall biomass production per area (ca 6 t DW per ha) and metabolic energy content (>10 MJ/kg) in the forage are larger compared with the traditional extensive grazing method, enabling increased stocking rates and the more profitable management of these grasslands. Crude protein, neutral detergent fibre, hemicellulose content and relative forage value are presented. The proportion of fibres was lower, and the proportion of crude protein was larger (10…12%) in the paddocks in which rotational grazing was used at the end of the vegetation period. The impacts of rotational grazing on local biodiversity require further study. We suggest rotational grazing for boreal growing conditions to elongate the grazing period.