INGENIEUR
“ In many ways the findings of the paper are predictable — many plant-focussed researchers have understood the links between wind dispersal of pollen and seed , and how those factors can contribute to or limit reproduction , dispersal , connectivity , and genetic diversity ,” wrote Jasmine Janes , an evolutionary biologist at Vancouver Island University who was not involved in the research , in an email to Popular Science . What ’ s interesting about this paper is that it brings many of these ideas together and tests them on a range of data sets so that scientists and forest managers can gain a deeper understanding of broad patterns .
Understanding how quickly the location range of a species of trees can migrate in response to climate change is important , says Kling , but it ’ s also important to consider how different genetic adaptations may be able to travel between populations of a given tree species . “ We can imagine that over time , perhaps populations in different climates and different parts of the species range have evolved different adaptations to survive better in those particular climates ,” says Kling . “ As climate warms , it ’ s going to be important for those genetic variants to be able to move around different populations in the species range , to help those other populations be better adapted to the warmer conditions of the future .”
Amazon Rainforest emitted more CO 2 than it absorbed - AFP
The Brazilian Amazon released nearly 20 % more carbon dioxide into the atmosphere over the last decade than it absorbed , according to a stunning report that shows humanity can no longer depend on the world ' s largest tropical forest to help absorb man-made carbon pollution .
From 2010 through 2019 , Brazil ' s Amazon basin gave off 16.6 billion tonnes of CO 2
, while drawing down only 13.9 billion tonnes , researchers reported in the Nature Climate Change journal .
The study looked at the volume of CO 2 absorbed and stored as the forest grows , versus the amounts released back into the atmosphere as it has been burned down or destroyed .
" We half-expected it , but it is the first time that we have figures showing that the Brazilian
Burning of trees in Amazon Forest
Amazon has flipped , and is now a net emitter ," said co-author Jean-Pierre Wigneron , a scientist at France ' s National Institute for Agronomic Research ( INRA ).
" We don ' t know at what point the changeover could become irreversible ," he told AFP in an interview .
The study also showed that deforestation — through fires and clear-cutting — increased nearly four-fold in 2019 compared to either of the two previous years , from about one million hectares to 3.9 million hectares , an area the size of the Netherlands .
Terrestrial ecosystems worldwide have been a crucial ally as the world struggles to curb CO 2 emissions , which topped 40 billion tonnes in 2019 .
Over the last half century , plants and soil have consistently absorbed about 30 % of those emissions , even as they increased by 50 % over that period .
Oceans have also helped , soaking up more than 20 %.
The Amazon basin contains about half of the world ' s tropical rainforests , which are more effective at soaking up and storing carbon that other types of forests .
If the region were to become a net source rather than a " sink " of CO 2
, tackling the climate crisis will be that much harder .
Using new methods of analysing satellite data developed at the University of Oklahoma , the international team of researchers also showed
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