Nature has built a unique biological museum in Maine, Foulde, in southern New Zealand. The discoveries made there millions of years ago can help us understand the changes that climate change is bringing to trees.
As of now, even during the Miocene 23 million years ago, the climate warmed. Arctic ice melted.
However, paleobotanists who studied plant fossils found that trees were able to adapt to a carbon-rich atmosphere. Trees used carbon dioxide and water as efficiently or even more efficiently than current trees.
Even in the current era of anthropocene, or human, the leaves of plants seem to use water more efficiently than before. Carbon dioxide acts as a fertilizer and trees grow faster.
However, the benefit may disappear in the near future, and water shortages are starting to limit growth, the researchers estimate.
Foulden A volcano erupted in the Maari region 23 million years ago. The eruption gave birth to a shallow crater that was filled with water. Tens of thousands of fossils were deposited in Lake Kraatterijärvi over 130,000 years. The leaves of the plants have remained mummified within the latent layers.
The latent layers are like a book about climate change.
Leaf fossils have been subjected to anatomical and chemical measurements that directly tell the state of the atmosphere and climate during leaf growth.
One Discovery Site tells only part of the truth, but fortunately plant fossils of the same era have also been found in Ethiopia and Panama. Scientists have been able to combine data from different places and refine their climate models.
Fossils the events of the time of formation compare in an interesting way with the present.
The carbon dioxide concentration at that time was at its lowest 450 parts per million and at its highest 550 parts per million. The average global temperature was 5-6 degrees higher than today.
Today, the concentration is 411, and it could be 500 parts per million by 2050.
A paleobotanist at the University of Connecticut who led the study Tammo Reichgelt and his colleagues took drilling samples from the 183-meter-thick layer at Folden Maari.
There were a total of 72 leaves from 18 tree species.
The leaves had been preserved so well that the researchers were able to determine the size of the air gaps. By opening and closing the gaps, the plant’s leaf regulates the exchange of gases with the environment. Carbon dioxide flows in through the air gaps. At the same time, water vapor flows out. Trees adapted to carbon dioxide concentration.
The study was published in August In Climate of the Past.
“Research provides additional information on the physiological response of trees to elevated carbon dioxide levels. It thus helps predict future vegetation responses to climate change, ”says the paleoecologist Maija Heikkilä From the University of Helsinki.
“There is a lot of need for such studies, as well as evidence for any phenomenon in general: with different methods, with different habits and with different species, to get an overall picture of events that facilitates human adaptation.”
In addition, climate change affects different species and environments in different ways.
Reichgelt’s study concerned tropical and temperate deciduous trees. They are very different and adapted to a different climate than our boreal species in the northern coniferous forest zone.
“[Kanadan] Studies of old cedar trees in Quebec suggest that water use by boreal trees also becomes more efficient as carbon dioxide levels rise, but carbon dioxide cannot be used efficiently due to lack of water and nutrients. Thus, the growth of trees did not increase, ”says Heikkilä.
Climate change has significantly increased the growth of Finnish forests in recent decades.
Finland trees are still their own chapter.
Professor of Plant Ecology Frank Berninger The University of Eastern Finland and colleagues have studied the efficiency of water use and evaporation in European forests during the anthropocene.
Anthropocene began when man, by his own actions, began to fundamentally modify the environment.
Berninger and his colleagues studies according to plant leaves have used water more efficiently. In this way, they are able to utilize the air without carbon dioxide as a fertilizer.
The researchers utilized carbon isotope measurements of the annual rings of the trees. Measurements were made at 23 locations. The network of points extended from Morocco to northern Finland.
The water use efficiency of conifers increased by 22 percent during the 20th century and that of deciduous trees by 14 percent.
Climate change has significantly increased the growth of Finnish forests in 1970–2010, the Natural Resources Center showed Luke’s research from 2017.
Environmental factors, such as rising temperatures and carbon dioxide concentrations and nitrogen deposition, explained the 37 percent increase in mineral soils.
Estimates of the carbon sink effect of forests can be overly optimistic.
The whole picture attempts are also being made to build on the changes in vegetation around the globe. In 2016, scientists from eight countries published satellite measurements score leaf cover of trees and other plants.
In the twenty years 1989–2009, the area of green cover had grown in most areas of the globe.
The fertilization effect of carbon dioxide without air accounted for 70 percent of the change. The rest was due to an increase in the amount of nitrogen and other changes in the climate, as well as hitherto unknown factors.
In the future, developments may not be straightforward. Rapid changes in carbon dioxide concentration and temperature bring with them side effects that threaten growth.
In the southern latitudes, long periods of heat and drought may be too much for the adaptability of plants.
Diseases and insects then attack the weakened plants and complement the destruction.
North forests appear to be a little more sustainable, according to studies.
Postdoctoral Researcher Lauri Lindfors From the University of Helsinki found in his dissertation that juniper is an actual drought artist, but pine also withstands drought well in both summer and winter.
Here, too, there is a threat of storm damage and pests. Even if damage is avoided, the fertilizing effect of carbon dioxide and drought tolerance also have their limits.
Growth gains may soon turn into growth losses, Professor of Forest Planning Timo Pukkala The University of Eastern Finland is evaluating the change in northern forests.
“Even without the devastating effect, it has been calculated that the growth-enhancing effect will fold in a few decades as water shortages begin to limit growth,” he writes. on his blog.
New confirmation of the estimate is given by an oven-fresh analysis of the annual ring material of the trees.
Researchers from nine countries, a researcher from the Natural Resources Center of Finland, participated in the work Samuli Helama. The data included 210,000 trees and 110 tree species, and the results were released last week In the journal Nature Communications.
It turned out that carbon dioxide does accelerate growth initially but at the same time shortens the life of trees. Estimates of the carbon sink effect of forests can be overly optimistic, the researchers say.
Whether hot or cold, humid or dry, some plants thrive.
Quantitative in addition to the changes, researchers are interested in the quality of future forests.
A large group of international researchers just looked at it In the journal Science the impact of climate change on the species population over the last 130,000 years. Researchers utilized “paleoarchive” or fossil data.
Natural archives reported that species ranges and numbers of individuals changed dramatically and some species became extinct. For example, a relative of the current spruce, the Critchfield spruce, disappeared from North America more than 15,000 years ago.
Research data also has many economic applications. In addition to plant adaptation reactions, the past provides information on the speed of geographical movement of plant zones, such as the “deciduous afforestation” of southern Finland.
There will also be information on plant diseases and forest fires as the climate changes.
“Based on the information, forest management, protection and management measures can be adapted in advance,” says Heikkilä.
Nature as a whole adapts to climate change. New species are developing to replace the extinct species.
Whether hot or cold, humid or dry, some plants thrive. Some desert plants connect at 46-degree heat, and some cold-climate plants at zero-degree coldness.
It is difficult for a person to keep up with the current changes. The transformation of the Miocene, which was studied by the Reichgelt group, lasted 100,000 years. Anthropocene will erode forests in a few decades.
Researchers and forestry companies are pursuing climate-resilient trees through artificial adaptation, ie processing, but that too is slow compared to the rate of change in the environment.
The aim is therefore to speed up breeding with modern genetic engineering, such as gene editing.
Last year, a number of researchers published in the journal Science petition to update forest certification criteria in line with scientific developments. They also suggested the possibility for genetically engineered trees to receive a certificate of environmental friendliness. If the proposal goes through, there will still be a lot of time for changes in the forests.
However, gene editing of trees is still in its early stages of research.