Do forests clean the air?

2001/05/24 Galarraga Aiestaran, Ana - Elhuyar Zientzia

• Ekologia
• Ingurumena

Two groups of American researchers, after studies in a pine forest, have shown that their beliefs were too optimistic. Research published in the journal Nature should be taken into account when calculating the damage caused by carbon dioxide emissions.

The team at Duke University of North Carolina analyzes a pine forest of the species Pinus taeda. The pine forest was divided into two and the unilateral pines remained at high concentrations of carbon dioxide (0.06%). The aim of the researchers was to compare the concentration of carbon dioxide with the growth of those who had a normal concentration (0.04%). In fact, when trees are growing they accumulate carbon in the trunk. However, the concentration of carbon dioxide in the medium was high, after three years of growth superior to the rest, stagnated.

Apparently, the decrease in food was what limited growth, especially nitrogen shortage. In addition, in times of drought, the high concentration of carbon dioxide was less pronounced.

Even if it seems untrue, increasing pollution improves the results in the experiment, because thanks to the nitrogen contained in acid rain, trees can assimilate this excess of carbon dioxide. However, the participation of other agents to consider has not been measured.

For example, half the amount of carbon absorbed by trees accumulates in the leaves. When falling to the ground, the second group of researchers wanted to see if the carbon of the leaves passes back into the air or if the soil is occupied. To do this, researchers from the Bowden School of Maine and Duke University analyzed the same pine forest and, once again, obtained negative results in terms of warming.

According to this study, although trees in a highly concentrated environment of carbon dioxide had a higher number of leaves, after their fall to the ground, they released carbon dioxide into the atmosphere in less than three years.

Despite the need for more research, it has been shown that what I saw in forests was wrong in solving the greenhouse effect and climate change problems. The increase in forests does not allow contamination.