Forest Restoration: Carbon, Water and So Much More

Forests and trees do so much more than simply capturing carbon. While carbon storage provides a vital service, a focus on the crucial role of carbon alone neglects the many other vital contributions forests make. For example, their role in sustaining biodiversity, contributing to local people, and maintaining the water cycle, require greater emphasis. In their essay Frontiers | Restoring deforested drylands for a wetter future – harnessing trees for credits, climate and water (frontiersin.org) , SUPERB’s Koen Kramer (LandLife Company) and Douglas Sheil (Wageningen Research and University) emphasize the importance of considering water alongside carbon when planning dryland restoration efforts. With the right tree species in the right locations, we can improve both carbon capture and the water cycle.

The authors argue that in case of drylands, changes in atmospheric water should be recognised as human-induced factor for enhanced global warming. Their argument is that vast areas of dryland forests have been cleared over the last 2 centuries, which has resulted in desiccation, i.e. reduced condensation and thus less cooling of the atmosphere.

In other words, human-induced deforestation enhanced the greenhouse effect of water vapor in the atmosphere and should therefore be recognised as direct effect determining climate change. If recognized, this effect can be expressed in CO₂ equivalents and existing markets can be used to fund restoration of deforested drylands.

This is, as the experts admit, a bold idea. The effects of trees and forests on local hydrology, albedo, and atmospheric moisture content is much debated in the scientific community as they depend on local orographic conditions, distance to sea, tree cover and species composition, and so on.

Nevertheless, at a larger scale, desiccation by deforestation and rewetting by reforestation is increasingly recognized. With the right tree species in the right locations, we can improve both carbon capture and the water cycle, emphasize Koen and Douglas. This could form the base to improve the land and lives of those living there. Water matters because everything else depends on it.