Nitrogen leaching and herbage production on intensively managed grass and grass-clover pastures on sandy soil in Finland

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How can forage production in Nordic and Mediterranean Europe adapt to the challenges and opportunities arising from climate change?

Climate change and its effects on grassland productivity vary across Europe. The Mediterranean and Nordic regions represent the opposite ends of a gradient of changes in temperature and precipitation patterns, with increasingly warmer and wetter winters in the north and increasingly warmer and drier summers in the south. Warming and elevated concentration of atmospheric CO2 may boost forage production in the Nordic region. Production in many Mediterranean areas is likely to become even more challenged by drought in the future, but elevated CO2 can to some extent alleviate drought limitation on photosynthesis and growth. In both regions, climate change will affect forage quality and lead to modifications of the annual productivity cycles, with an extended growing season in the Nordic region and a shift towards winter in the Mediterranean region. This will require adaptations in defoliation and fertilization strategies. The identity of species and mixtures with optimal performance is likelyto shift somewhat inresponse to altered climate and management systems. Itis argued that breeding of grassland species should aimto (i) improve plantstrategies to cope with relevant abiotic stresses and (ii) optimize growth and phenology to new seasonal variation, and that plant diversity at all levels is a good adaptation strategy

Consumo de forragem e produção de leite de vacas em pastagem de azevém-anual com duas ofertas de forragem Herbage intake and milk yield of dairy cows grazing Italian ryegrass at two herbage allowances

Avaliou-se o efeito de duas ofertas de forragem (25 e 40 kg MS/vaca.dia) sobre o consumo de forragem e a produção de leite em vacas pastejando azevém-anual. Utilizou-se o método rotacionado, em delineamento experimental de dupla reversão, com três períodos de 12 dias e dez vacas da raça Holandesa no terço médio de lactação. O consumo de forragem foi estimado pela produção fecal e pela digestibilidade da forragem ingerida e a produção de leite foi medida diariamente. A biomassa e a altura do dossel antes do pastejo não diferiram entre as ofertas de forragem. A altura pós-pastejo foi maior na oferta de forragem de 40 kg MS/vaca.dia, o que determinou desaparecimento de forragem equivalente a 49,0% nessa oferta de forragem e a 69,0% na oferta de 25 kg MS/vaca.dia. O consumo individual de matéria seca (MS) da forragem foi 11,9 e 16,6 kg/dia e a produção de leite, 18,4 e 21,1 kg/dia nas ofertas de 25 e 40 kg MS/vaca.dia, respectivamente. Vacas leiteiras em pastagem de azevém com alta oferta de forragem podem ingerir mais de 16,0 kg de MS e produzir mais de 20 kg de leite/dia. A produção de leite reduz aproximadamente 0,2 kg a cada kg de diminuição na MS de forragem oferecida.<br>The effect of two herbage allowances (25 and 40 kg dry matter/cow.day) were assessed on the herbage intake and milk yield of dairy cows grazing Italian ryegrass. A rotational grazing system was used, according to a Change Over procedure with three 12-day periods and ten Holstein cows in mid-lactation. Individual herbage intake was estimated from fecal output and the digestibility of the selected herbage and the milk yield was measured daily. Pre-grazing sward height and herbage mass at ground level did not differ between treatments. Post-grazing sward height was higher 40 kg dry matter/cow.day and the pasture disappearance rate from the initial sward was 49.0% and 69.0%, respectively. The individual dry matter intake of the herbage was 11.9 and 16.6 kg kg/day and the milk yield was 18.4 and. 21.1 kg/day at the allowances 25 and 40 kg dry matter/cow.day, respectively. Dairy cows grazing Italian ryegrass pasture, with a high forage allowance, can eat more than 16.0 kg DM/day and produce more than 20 kg milk/day. The milk yield decreased around 0.2 kg per kg of reduction in DM offer