Every year, in a process known as senescence, the leaves of deciduous trees turn yellow, orange, and red because they suspend growth and extract nutrients from the vegetation. Lei senescence also marks the end of the period when plants absorb carbon dioxide through photosynthesis.
Global warming has led to longer growing seasons – two weeks earlier than 100 years ago, when spring leaves appeared on European trees, researchers said.
“Previous models have predicted that autumn will be warmer and warmer in the coming century – the growing seasons will be longer overall, and autumn will be two to three weeks later,” said ecosystem scientist Konstantin Zohner.
However, Zohner too A group of researchers said their findings could contradict this prediction.
Using a combination of field observations, laboratory tests, and modeling, the experts identified six European deciduous tree species: European horse chestnut, silver birch, European beech, European larch, English oak, and rowan.
Experts have found that spring-summer productivity, temperature, and light amounts, which result from high carbon dioxide, can lead to early loss of tree leaves.
Sohner said fall temperatures and day lengths are the main environmental factors that cause tree loss. Now, researchers have identified a third factor – a “self-regulated” productivity.
“Now we see this third big system going on – (Tree) productivity is self-regulating. If you already have more going on in the spring and summer – if the plant absorbs more CO2 they will lose leaves earlier in the spring and summer,” he said.
“It’s a system we see in humans too – if you start eating early, you’ll fill up earlier,” he said.
Sohner said the trees have production limitations.
“We can’t put more and more CO2 into the atmosphere, (expect) trees will do even more – there are limits,” he said.