We have already mentioned before the admirable approach of large polluters who, rather than revising models intrinsically harmful to the environment, compensate for their impact by planting trees (see here: https://www.mangrove-foundation.com/post/ regarding-the-efficiency-of-cheap-greenwashing). If we had criticized the aspect of pure communication, we must also mention the problem of implementation.
Indeed, some forests, with rich biodiversity, are chopped off either massively for agricultural or industrial purposes, or over time by local populations to meet their needs for firewood or construction wood. In all cases, the impact on biodiversity is dramatic, and in the countries where we operate, desertification follows, or at least massive erosion occurs.
When we finally decide to correct these errors, reforestation efforts often consist of plantations of a single species, sometimes chosen for its rapid yields, while a rainforest can take up to 65 years to regrow and massively absorb GHG. There also exist collateral damages. The example of eucalyptus is interesting. Frequently chosen for its rapid growth and economic profitability, this tree is generally planted on land where it is not endemic, and which is not suitable for hosting it. Requiring considerable quantities of water, it then dries up the ground water and enters into competition with local species.
Thus, in Europe, the replacement of native broad-leaved oaks by rapidly growing conifers has certainly led to a 10% increase in forest cover on the continent compared to the pre-industrial era. However, these new trees absorb much less carbon than the original species. On the other hand, they capture heat more efficiently, thus intensifying the effects of global warming. They are so ugly, these well-aligned, single-species tree plantations, and all the same size. They are moreover “empty forests" because the flora and fauna cannot grow there. This was the error of China with its "Great Green Wall", intended to slow down the advance of the Gobi Desert.
So, unless we are satisfied with a communication campaign in which polluters are promoting their new ecological virtue, we must therefore avoid falling into these simplistic methodologies.
The efficiency of reforestation then implies the development of multifunctional forests, capable of satisfying a wide variety of services (including wood production) and at the same time constituting ecosystems which function thanks to complex interactions, between trees, animals, soil and human microorganisms, but which can be monitored and controlled.
These forests can also function thanks to the mastering of assisted natural regeneration, meaning from the seeds produced by the local trees which are then favored or eliminated according to the final quality of the ecosystem sought. A kind of "forest agroecology", as we have implemented it within the framework of our projects in Senegal and Mali.