Extreme weather postpones flowering fime of plants

Science Daily: Extreme weather events have a greater effect on flora than previously presumed. A one-month drought postpones the time of flowering of grassland and heathland plants in Central Europe by an average of 4 days. With this a so-called 100-year drought event equates to approx. a decade of global warming. The flowering period of an important early flowerer, the common Birds-foot Trefoil (Lotus corniculatus) was even shortened by more than a month due to heavy rain and started flowering early by almost one month. In a study conducted by the University of Bayreuth and the Helmholtz-Centre for Environmental Research (UFZ) researchers came to this conclusion.

Using experimental plots in Bayreuth the researchers generated artificial heavy rain and drought in their experiment and the effects on ten different plant species were observed accordingly over a two-year period. With climate change it is expected that such extreme weather events will increase in frequency and intensity, which entails a risk for animal-plant interactions and ecological services. In this respect it is conceivable that the synchronisation between flowering plants and pollinating insects could be uncoupled and the rhythm of evolution lost due to extreme weather events. For example, the activity of pollinating insects is determined more so by temperatures as opposed to changes in rainfall, as researchers have reported in the scientific journal Global Change Biology.

Changes to the flowering time of plants are regarded as one of the most evident signs of global warming. Other studies have already shown that since 1960 the beginning of Spring has been postponed in the northern hemisphere by an average of 2.5 days per decade. Although forecasts like the IPCC-Report 2007 reckon with a more considerable increase in extreme weather events, the effects of such events on ecology have previously been researched very little. Scientists working with Prof. Anke Jentsch have therefore set up an experimental site in the ecological botanical garden in Bayreuth, to investigate the effects of extreme weather events such as droughts or heavy rains….

Bird's foot trefoil, shot by Circeus, under the Creative CommonsAttribution ShareAlike 2.0 Canada"Licence