Nathalie Machon, ecologist: "A city is only habitable if there is biodiversity"

She spends her life studying the benefits of nature in the city and convincing as many people as possible of its usefulness.

Nathalie Machon is professor of ecology at the National Museum of Natural History.

She has just directed the publication of “Sauvages de ma rue” (Editions du Passage) and co-wrote “Where biodiversity is hidden in the city” with Philippe Clergeau (Editions Quae).

Do you observe an awareness of city dwellers on the importance of trees in the city?

NATHALIE MACHON.

I perceive a much greater involvement of the municipalities on these issues.

They seek to enhance their tree heritage and to take care of it.

This is partly out of concern for the satisfaction of their townspeople, who are more interested in these questions.

But also because the new elected officials at the last municipal elections defend deeper convictions in terms of ecology.

Even those who weren't convinced by these questions get started.

More and more towns are drafting “tree charters”, making an inventory of the tree heritage, but society is progressing slowly, some are not mobilizing at all.

Read alsoIn Île-de-France, general mobilization to save nature in the city

Do city dwellers know better about the benefits of trees?

Unfortunately, there is a lack of awareness of these benefits.

I am sometimes alerted, as recently in Savigny-sur-Orge

, of tree cutting for simple reasons of dissatisfied neighbours.

However, we are here to help associations argue, and it works!

Living conditions in the city are greatly improved by biodiversity.

There is a very strong link between quality of life, health of inhabitants and quality of biodiversity.

For example, during the heat wave of 2003, there were more deaths in the streets without trees: the trees regulate the temperature.

Allergies are also fewer if the area is more vegetated.

Children are used to it and allergenic pollens are diluted among others.

The tree in the city also has some disadvantages, such as the leaves to be picked up in the fall or the sidewalks that open up because of the roots.

How to minimize the disadvantages?

The choice of species is essential for them to be better adapted, the variety of plantations is also important.

But residents also need to be taught not to be afraid of a spider or to rant about bird droppings on their car.

These nuisances are largely minimal compared to the benefits!

A city is only habitable if there are green spaces and biodiversity.

The richer and more present the biodiversity networks are, the more they serve humans.