False Autumn

Autumn has arrived earlier than ever this year.

With global warming, just like any other living creatures trees also are affected by heat waves. High heat has serious impacts on trees. One of them is on leaf level. Photosynthesis is reduced, photooxidative stress increases, leaves shed and growth rate of remaining leaves decreases. When a tree faces heat waves and negative effects of heat stress, it can lead to mortality. Although some tree species show tolerance to thermal stress, those are still under the influence of climate change. Excessive heat can cause a decrease in growth, leaf development and leaf area. So the direct effects of high temperature can be severe. The heatwaves, in terms of number and intensity have increased throughout this century and it seems that they will continue to increase.

Let me tell you about trees’ surviving mechanisms. Trees may pass water from their leaves to the air. This may cause air bubbles to form in the channels leading from the roots to the leaves. Those bubbles break the chain of water molecules which are required to keep water moving upward through a tree.

Trees respond to high heat closing the openings in their leaves to limit water loss. By doing this their ability to photosynthesis is shut down. They need coolness to be able to make food.

Why we should protect the trees?

Imagine yourself on a summer day, a very hot day, you are outside and looking for a shadow for relief. Then you find a shadow of a tree, a shelter against the heat. But what about trees? They are exposed to direct sunlight. They try to survive in changing temperatures and climate change. They can lower air temperature in cities to lifesaving degrees. Also they reduce electricity demand for degrees by helping avoid potential power outages during heat waves and sparing money and emissions.

The trees are under stress

Of course it is in their nature to fall leaves in the autumn. The greens in the leaves give way to reds, yellows, oranges and browns as the tree withdraws the sugars into its branches and trunk. Yet it is not normal that they shed their leaves early. Lack of rain, has a very dry summer so leaves fall from trees and trees go survival mode early. In the UK, this summer it was above 40 degrees. And this summer millions of trees were deprived of water and shed their leaves early to conserve sugar and water. According to the experts, early fall is a sign of stress, as trees attempt to retain moisture amid the soaring heat and low rainfall. They shed their leaves prematurely to conserve water and energy.

So you see, it is all about survival instinct, they are trying to protect themselves. We should embrace our responsibility and think about trees, using electricity and non-renewable energy. Because they are all connected to each other. Start generating clean energy and at least you do something for nature!