Forests, trees, water: our life on earth depends on them
What is a forest? An ecosystem formed by trees, animals, grasses, shrubs, fruits, microorganisms in direct relationship with each other. The forest is a complex ecosystem in a delicate balance with all the elements of the planet and in particular with the climate and, consequently, with climate change. Forest ecosystems are heavily influenced by drought phenomena and this is a problem that concerns us all. No one excluded.
Forests: a delicate balance fruit of continuous evolution
A process well known to those who deal with forestry sciences is the so-called selective pressure: in all forest ecosystems there are organisms that are better adapted to the typical characteristics of those particular environments. All plant and animal species living in woods and forests have undergone evolutionary adaptations that have allowed them to grow, reproduce and adapt, but above all to assume a form that is suitable for that particular habitat: it is evolution that allows forests to live in that delicate dynamic balance made of interconnections between all the living beings they host. The ability of the forest to limit the negative impacts of climate change is a quality that derives precisely from this ability to adapt.
Trees are thirsty
But this delicate balance is threatened by a number of factors, almost all of which are anthropogenic: man’s emission of greenhouse gases – carbon dioxide, methane and nitrous oxide. Rising temperatures, altered precipitation patterns, extreme events such as tornadoes and hurricanes, heat waves and forest fires are only the most visible consequences of climate change. The most worrisome, drought, is a phenomenon that particularly affects trees that are paying too high a price and the cause is our behavior: trees, in order to survive, must overcome a great challenge.
The challenge of trees
Just as with all living things, trees also live thanks to and above all to an element that is fundamental to them: water. But what happens when trees don’t have enough water? They slow down photosynthesis, an ancient process that gives trees life. There are no trees without water. There is no life without photosynthesis. And we humans cannot live if we lack or “jam” even one of these two elements.
Reduced photosynthetic activity is the most obvious and considered effect related to drought because it reduces the amount of wood produced by the tree and, more importantly, reduces carbon sequestration in forest biomass. In a study conducted by Los Alamos National Laboratories in the U.S.A. it is underlined that periods of intense drought – events that are increasing a lot during the last years – correspond a substantial reduction of carbon that trees are able to absorb thanks to photosynthesis: the data, impressive, indicates that the reduction is more than three times compared to the consequences of drought studied so far.
More frequent and longer drought periods are able to directly cause the death of trees, less and less able to absorb CO2: we can call it “carbon starvation”. Alteration of the reproductive cycle of trees, flowering, pollination, fructification, seed production and probability of survival of young plants are just some of the cascading effects that, if we do not reverse course, will soon become visible in the years to come.
How can we help forests and trees survive?
We need a change of course, without ifs and buts. The change starts first of all from institutions, governments, international and supranational organizations: without their intervention it will be almost impossible to limit the effects of climate change and drought. We need laws, regulations, incentives, protection of forests. But we citizens can also do our part, changing our consumption and purchasing habits, our diet, the way we look at, feel and live nature, woods and forests.
Planting new trees and protecting existing forests is one of the best ways to fight the climate crisis, help trees to survive drought periods and stop deforestation.