Afforestation falls short as a biodiversity strategy [View all]

[NNadir]

An opinion piece in this week's issue of the journal Science comments on the proposal to address climate change by planting oodles of trees: Afforestation falls short as a biodiversity strategy
(Susana Gómez-González1,2,*, Raúl Ochoa-Hueso1, Juli G. Pausas3, Science 26 Jun 2020: Vol. 368, Issue 6498, pp. 1439)

I believe it's open sourced.

An excerpt:

The recent EU Biodiversity Strategy for 2030 (1) recognizes the importance of biodiversity for increasing our resilience to natural disasters and pandemics and, thus, for human well-being. Although it proposes ambitious measures such as reversing pollinator decline and controlling invasive species, it also introduces the ill-advised idea of planting 3 billion trees.

Massive tree plantation programs (2, 3) have been strongly criticized by the scientific community for their negative ecological and economic impacts and their limited role in climate change and CO2 mitigation (4–8). The specific number of trees proposed in the EU Strategy suggests a lack of a serious, science-based ecological assessment of actual restoration needs. Meeting such a target could threaten biodiverse treeless ecosystems (4, 6, 7, 9) and would waste an opportunity to implement ecologically sound management practices to restore fully functionally integrated mosaics of natural, seminatural, and sustainable agricultural ecosystems.

Massive tree planting could also substantially change the fire regime, especially given the increasing frequency of heat waves and droughts in an area with high population density (10). The probability of large intense fires that threaten biodiversity and human assets is largely influenced by the type, amount, and continuity of biomass...

I personally believe that biomass can play a constructive role in removing carbon dioxide, if, and only if, it is does so safely in an environmentally sustainable manner. Let's be clear, combusting biomass is neither safe nor sustainable, but there are many things to recommend using the large surface areas that biomass can accommodate in a setting of pyrolysis or steam reformation.

However biodiversity is important, and strategies like making monoculture palm oil plantations out of rain forests to generate "renewable biodiesel" doesn't cut it, nor does destroying the ecosystem of the Mississippi delta to make "renewable corn ethanol," nor does putting service roads through virgin forests to install and haul away wind turbines every twenty years with diesel trucks doesn't cut it.

Possibly the authors are on to something.