Peatlands trap carbon dioxide, even during droughts
Although peatlands make up only 3 percent of the Earth’s surface, they store one third of the soil carbon trapped in soils globally. Preserving peatlands is therefore of paramount importance for mitigating climate change, provided that these vulnerable environments are not themselves threatened by global warming. To better determine this risk, two French scientists, including Vincent Jassey, a CNRS researcher at the Laboratoire Ecologie Fontionnelle et Environnement (CNRS/Université Toulouse III—Paul Sabatier/INP Toulouse), studied carbon uptake by the two main species of moss that make up the Le Forbonnet peatland in Frasne (Jura). They discovered that when temperatures were high and also during droughts, the two Sphagnum species behaved in opposite ways: Sphagnum medium resists drought, whereas the photosynthesis of Sphagnum fallax is negatively impacted; conversely, in very hot but humid weather, photosynthesis, and thus carbon uptake, in Sphagnum fallax increases, whereas t...