The effect of climatic factors on the hectare yields of barley, oats and spring wheat in Finland in 1972-77

Abstract

The effects of certain climatic factors on the hectare yields of barley, oats and spring wheat are presented. The effect of the temperature conditions during the growing period is clear and follows an optimum curve; the optimal mean temperature of the growing period is about 14.5‑15°C. The effect of the amount of effective precipitation during the first 60‑65 days of the growing period also follows an optimum curve; the optimal amount during this period is approximately 75‑80 min. Fine weather at the end of the growing period has a beneficial effect. The unfavourable effect of rainy conditions during harvesting is visible to some extent. A clear trend can be seen following the general temperature conditions; this trend results from the fact that in southern Finland more productive varieties are cultivated, the cultivation methods are more intensive and the edaphic condi­tions on average more profitable. Climatic factors account for 50 % of the hectare yield fluctuations in the case of barley (61 % in a more consistent submaterial), 38 % in the case of oats and 52 % in the case of spring wheat.