Green areas on our planet, especially big and small forests, are very important because they are the main and most effective way to fight air pollution, but the expansion of cities and the development of the world economy often disregards this.
During the summer, we have witnessed helpless several fires around the world that have caused unimaginable damage to natural ecosystems, but it’s not just that. Most of all, they have greatly reduced the green areas that guarantee clean air every day to our planet, cleaning it from the pollutants produced every day. This is particularly important since the recent pandemic has highlighted how air pollution can be a vehicle of spread for future diseases that can strike hardest where the air is most polluted.
Moreover, another big threat to these green areas is the phenomenon of deforestation, which has still been greatly put in place despite forests being fundamental to human survival. And even if man has been able to “recreate forests” with different materials, such as the air purifying technology Airlite, also capable of tackle embodied carbons, the power of trees in terms of positive impact on our daily lives cannot be reproduced easily.
Let’s now see how deforestation is impacting one of the biggest green areas in the world.
Deforestation in Brazilian Amazon
As Flavia Milhorance pointed out, deforestation in the Brazilian Amazon has hit the highest annual level in a decade, a new report has shown, despite increasing global concern over the accelerating devastation since President Jair Bolsonaro took office in 2019.
Between August 2020 and July 2021, the rainforest lost 10,476 square kilometers – an area nearly seven times bigger than greater London and 13 times the size of New York City, according to data released by Imazon, a Brazilian research institute that has been tracking the Amazon deforestation since 2008. The figure is 57% higher than in the previous year and is the worst since 2012.
“Deforestation is still out of control,” Carlos Souza, a researcher at Imazon said. “Brazil is going against the global climate agenda that is seeking to urgently reduce greenhouse gas emissions.”
Souza called for the urgent resumption of government actions to stop the destruction, including the enforcement of illegal agriculture-led deforestation in the region, which has been impaired by budget cuts for the Environment Ministry and environmental protection agencies.
Even as he faces accusations of systematically dismantling environmental protections, Bolsonaro has deployed thousands of soldiers to combat illegal deforestation and fires.
But the policy has proved ineffective, said Marcio Astrini, the executive-secretary of the organisation Climate Observatory. “The data shows that it didn’t work,” said Astrini. “No army operation will be able to mask or reverse the attacks of the federal government against the forest.”
Astrini said that the deforestation rates in 2021 are expected to be almost 50% higher than in 2018, before Bolsonaro took office.
In June, then-environment minister Ricardo Salles resigned amid a criminal investigation over allegations that a police investigation into illegal Amazon logging was blocked.
But the ministry’s leadership “hasn’t shown any progress,” Astrini said. “The measures that benefit the export of illegal timber – the reason why Salles had to leave office – are still in place,” he said.
The new figures were released as lawmakers held a public hearing to push for changes in Brazil’s environmental policies. “We are going through a very tough moment in Brazilian history. There’s a lot of denialism, and many attempts to weaken our environmental policy,” senator Eliziane Gama told the hearing.
Could miniature forests help air-condition cities?
City air is in a sorry state, The Economist declared. It is dirty and hot. Outdoor pollution kills 4.2m people a year, according to the World Health Organisation. Concrete and tarmac, meanwhile, absorb the sun’s rays rather than reflecting them back into space, and displace plants which would otherwise cool things down by evaporative transpiration. The relentless spread of buildings and roads thus turns urban areas into heat islands, discomforting residents and exacerbating dangerous heatwaves, which are in any case likely to become more frequent as the planet warms.
A possible answer to the twin problems of pollution and heat is, of course, planting trees. Their leaves may destroy some chemical pollutants and they certainly trap airborne particulate matter, which is then washed to the ground by rain. And trees cool things down. Besides transpiration, they provide shade. Their leaves have, after all, evolved to intercept sunlight, the motor of photosynthesis.
To cool an area effectively, though, trees must be planted in quantity. In 2019 researchers at the University of Wisconsin found that American cities need 40% tree coverage to cut urban heat back meaningfully.
One group of botanists believe they have at least a partial solution to this lack of urban vegetation. It is to plant miniature simulacra of natural forests, ecologically engineered for rapid growth. Over the course of a career that began in the 1950s their leader, Miyawaki Akira (recently died), a plant ecologist at Yokohama National University, in Japan, has developed a way to do this starting with even the most unpromising derelict areas. And the Miyawaki method, as it has become known, is finding increasing favor around the world.
The Miyawaki method skips some of the early phases and jumps directly to planting the kinds of species found in a mature wood.
Using a wide mix of species, not all of them trees, is important. Most plantations, having been created for commercial purposes, are monocultures. But trees, shrubs and ground-covering herbs all coexist in natural forests, and the Miyawaki versions therefore have this variety from the start. Not only does that pack more greenery into a given space, it also encourages the plants to grow faster—for there are lots of positive ecological relations in a natural forest. Vines rely on trees for support. Trees give shade to shrubs. And, beneath the surface, plants’ roots interact with each other, and with soil fungi, in ways that enable a nutrient exchange which is only now beginning to be understood.
As well as trying to encourage the development and creation of green areas in built-up areas, we can also turn to new building technologies to help combat pollution. As we’ve seen, there are several innovative materials and techniques on the market, but we need a strong political and social impetus to go in this direction.
Public opinion must demand more sustainable choices for the future of cities to ensure better living conditions for all.
Read the full articles here:
- Flávia Milhorance, in The Guardian, August 2021, Deforestation in Brazilian Amazon hits highest annual level in a decade (https://www.theguardian.com/profile/flavia-milhorance);
- The Economist, Science & technology,
July 2021, Urban environments. Could miniature forests help air-condition cities? (https://www.economist.com/science-and-technology/2021/07/01/could-miniature-forests-help-air-condition-cities.