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Long-term changes of plant phenological phases determined by complex interactions of environmental factors are in the focus of recent climate impact research. There is a lack of studies on the comparison of biogeographical regions in Europe in terms of plant responses to climate. We examined the flowering phenology of plant species to identify the spatio-temporal patterns in their responses to environmental variables over the period 1970-2010. Data were collected from 12 countries along a 3000-km-long, North-South transect from northern to eastern Central Europe. Biogeographical regions of Europe were covered from Finland to Macedonia. Robust statistical methods were used to determine the most influential factors driving the changes of the beginning of flowering dates. Significant species-specific advancements in plant flowering onsets within the Continental (3 to 8.3 days), Alpine (2 to 3.8 days) and by highest magnitude in the Boreal biogeographical regions (2.2 to 9.6 days per decades) were found, while less pronounced responses were detected in the Pannonian and Mediterranean regions. While most of the other studies only use mean temperature in the models, we show that also the distribution of minimum and maximum temperatures are reasonable to consider as explanatory variable. Not just local (e.g. temperature) but large scale (e.g. North Atlantic Oscillation) climate factors, as well as altitude and latitude play significant role in the timing of flowering across biogeographical regions of Europe. Our analysis gave evidences that species show a delay in the timing of flowering with an increase in latitude (between the geographical coordinates of 40.9 and 67.9), and an advance with changing climate. The woody species (black locust and small-leaved lime) showed stronger advancements in their timing of flowering than the herbaceous species (dandelion, lily of the valley). In later decades (1991-2010), more pronounced phenological change was detected than during the earlier years (1970-1990), which indicates the increased influence of human induced higher spring temperatures in the late twentieth century. [ABSTRACT FROM AUTHOR]

Abstract: We analyze trends in crop yields and yield variability of barley, maize, oats, rye, triticale and wheat in Switzerland from 1961 to 2006. It shows that there have been linear increases in crop yields since the 1960s. However, yields of barley, oats, rye, triticale and wheat have leveled off in Switzerland since the early 1990s, which contrasts linear trends in cereal yields that is usually assumed for Europe. We show a relationship between the introduction of agricultural policy measures towards environmentally friendly cereal production that fostered widespread adoption of extensive farming practices and the observed leveling-off of crop yields. Thus, this paper emphasizes that agricultural policy can be an important reason for slowing crop yield growth. Agricultural policy measures will be one of the key driving forces of future crop yields. Thus, the potential leveling-off of crop yields that is indicated in this study should be considered in analyses of future land use and food supply as well as in the evaluation of agri-environmental measures and policy reforms. [Copyright &y& Elsevier]