Madrid, 13 feb ( EFE).-A team of researchers, with Spanish participation, has concluded that forest ecosystems suffer the consequences of disruption, as the logging of trees, for decades, even centuries, and that the current effects of climate change overlapped the past sequels.
These are some of the findings of a study that publishes the magazine “PNAS”, which also confirms the difficulty when it comes to discern, in systems that have been subjected to shocks for a long time between the effects of the current climate change and those of past human actions.
Susana Bernal, one of the authors of this work, explained to Efe that the interesting thing about the study is that it is a “effect clear” of climate change on forest ecosystems, but “not enough” to explain the changes observed.
And this is the case, according to Bernal, because ecosystems have “inertia” and respond slowly to disturbances that have already suffered in the past, as the felling of trees in the early 20th century.
To arrive at these conclusions, the researchers analyzed data from 50 years – climate, atmospheric deposition and export of nutrients – and forest inventory of Hubbard Brook Experimental basins, in the northeast of the us for two years.
One of the analyzed variables was the change in the efficiency of inorganic nitrogen, in particular nitrate retention.
According to Bernal, nitrogen is an essential nutrient for all living beings in a system.
In addition to the growth of forests, influencing the capacity of absorption of carbon in ecosystems.
“The ability of forest ecosystems to retain more carbon in the atmosphere is limited by the availability of other essentials, such as nitrogen or phosphorus”, said the researcher, who undertook this work with a scholarship to Princeton University.
Cited American basins, “perhaps the most studied in the world and that more information is available”, have experienced a drastic decline in the export of nitrogen in recent decades (around 90 per cent), according to Bernal.
Scientists have estimated that as much global warming could explain 40 percent of the decline in the export of nitrogen, usually occurs through the water of the rivers, and on the other hand at least a 60 percent might result of long-term logging effects.
Understand the complexity of the interactions between these disturbances and past is today one of the most difficult scientific challenges, said Bernal.
The study also participated the Cary Institute of ecosystem studies (USA). EFE
