This forests percentage of planet absorbs CO2 from atmosphere and thus helping to combat climate change. However, something is changing and This great “vacuum cleaner” of carbon dioxide begins to show irregularities in key areas of the planet.. This imbalance worries scientists.
A study published this week in the journal Nature has identified clear signs that carbon sequestration is at risk of destabilization in large areas of the Earth. The study shows that In some areas, carbon sequestration has changed drastically in recent years; the moments when plant productivity is high (high eclipse) and the others less (low eclipse). The authors warn that this variability is a sign that ecosystems may be at risk of destabilization and divergence, causing sudden changes.
“For example, in Mediterranean ecosystems, we may see forests turning into shrubs without the ability to revert to their original forest forms,” says Marcos Fernández, a CREAF researcher and collaborator at the University of Barcelona, first author of the study. “We also detected another signal in these areas, a an increase in its “memory” (temporary autocorrelation) indicates that each value is increasingly correlated with the previous one; such that if one value is decreasing, the next will decrease even more.“.
Among the regions of imbalance, the Mediterranean
The study confirms that the areas most at risk of destabilization have less forest, more crops, are warmer and are subject to greater increases in the variability of their temperatures; this may be related to an increase in extreme weather events such as waves. hot and cold. These regions would be Mediterranean region, eastern region of East Africa, west coast of North America and Central America, India and Pakistan or Southeast Asia.
To conduct the study, the research team worked with global data from two global atmospheric inversion models (CAMS and CarboScope) on the net production of ecosystems for the period 1981-2018. Also data on clean production of ecosystems of a set of 12 dynamic models of global vegetation (TRENDY).
Unstable nature limits carbon sequestration
The study shows that regions with the highest destabilization potential have seen their carbon sequestration capacities compromised in recent years. On the contrary, regions that tend to be less volatile (the Amazon or central and northern Europe, among others) have increased their carbon sequestration capacity.
“In the Amazon example, we see it losing less and less, although it loses carbon on average over the runtime. because the system is now less volatile than before,” says Josep Peñuelas, CSIC research professor at CREAF.
“Being able to predict the carbon cycle is key to tackling climate change. We do not know whether these abrupt changes will lead to changes in climate or the capacity of plants to sequester carbon. potential destabilization of large areas of the biosphere harder predictionsbecause it greatly increases variability,” comments Jordi Sardans, who is also a writer and CREAF researcher.
Does more biodiversity mean more stability?
In ecology, it is always said that the most biodiverse ecosystems with the greatest diversity and richness of species are more stable and productive and therefore have a greater capacity to sequester carbon. In this study we wanted to confirm this in all the regions of the world studied, and it was seen that highest rates of carbon sequestration occur in regions with moderate biodiversityWhere biodiversity is very high, such as the tropics, this carbon sequestration capacity is lower.
According to the researchers, this may be due to: positive impact of biodiversity on decomposition and respiration in tropical ecosystems may offset the positive impact on photosynthesisdoes not occur in other ecosystems. On the other hand, this study suggests that contrary to popular belief, the maximum variability in carbon sequestration also occurs in regions with moderate biodiversity. Given the global scale of this study, it is very difficult to understand the mechanisms behind these results.
Reference work: DOI : 10.1038/s41586-023-05725-1 2021-11-17874
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