Interview: "I try to weave trends together"

Editor’s note: This article was originally published in BioNieuws on January 17, 2025. This version has been translated into English.

Nadina Galle is making waves. Through podcasts, public appearances, and now a new book, the Canadian-Dutch ecological engineer is spreading the word about her concept: the Internet of Nature.

Written by Prof. Menno Schilthuizen

She holds her left hand vertically and presses the palm against the outstretched fingers of her right hand, causing them to bend. This is how ecological engineer Nadina Galle (1992) visualizes how, in Boston—where she conducted her Ph.D. research—the asphalt typically extends all the way to the base of street trees.

"This creates a concave shape that directs water and fallen leaves away from where the tree’s roots need them." It's just one of many problems she observes affecting urban trees worldwide. Another major issue is the lack of healthy soil.

"In Toronto, where I studied, half the city is built on a landfill. Everything I learned during my soil science courses at the University of Amsterdam (UvA) doesn’t apply there. The idea that you can take a core sample and neatly see the different soil layers is laughable. In Boston, too, trees grow on waste, rubble, and all sorts of debris—but not on actual soil!"

Sensors

In her new book, The Nature of Our Cities (published in Dutch as De natuur van onze steden in October 2024), the first few chapters focus on urban trees and their challenges. But just as importantly, she highlights the technology available to monitor and manage the millions of trees in cities.

One example is sensors: "With sensors, you can measure oxygen levels, temperature, pH, and moisture levels in real time. Moisture, in particular, is the determining factor in a tree's health. Many trees can withstand heat waves or insect infestations, but only if they have enough moisture."

This is an example of what she means by her concept Internet of Nature—using technological networks to monitor, manage, and protect both the living and non-living aspects of urban nature.

Her book—which she remarkably wrote in under nine months (she signed the contract the same week she became pregnant and submitted the manuscript on the day her son was born)—is full of global examples.

• In Singapore, seven million trees are monitored using LiDAR (Laser Imaging Detection and Ranging), reducing incidents of falling branches and trees by 90%.
• In New York, the city's parks department developed a method to calculate, in dollars, the value of ecosystem services—the free benefits nature provides, such as air quality improvement, rainwater retention, and heat stress reduction.
• In Melbourne, 70,000 trees have email addresses, allowing residents to report problems—but unexpectedly, many also began writing love letters to the trees.

Beyond vegetation, her book covers topics like the urban heat island effect, the mental and physical health benefits of urban nature, forest bathing, wildfire risks, biodiversity monitoring, and other technological approaches to improving urban livability.

"Even in Boston, trees grow on waste, rubble, anything but normal soil!"

She often tells these stories through personal encounters with local residents, ecologists, engineers, and city officials. This personal approach makes her writing particularly engaging—she writes with disarming honesty and shares much of herself.

For instance, she describes her visit to Maastricht, where she confronts traditional land managers of the urban greening project De Groene Loper, a highway overpass turned green space. Their initial reaction? "No sensor can tell me what I can't already see with my own eyes."

But after an experiment (and a bet over a meal of local zuurvlees), where all the sensor-equipped trees survived, while many trees without sensors died, even the most old-school arborists became convinced of the technology’s value.

A multi-faceted approach

Her book is just one way she spreads her message: "I try to connect trends and communicate about them as widely as possible," she explains.

She has held or holds academic positions at MIT's Senseable City Lab, the University of Amsterdam, and University College Dublin. She has taught a winter course on the Anthropocene at the UvA, hosts the Internet of Nature podcast, now in its fifth season, and is a TED Talk speaker.

And it's getting noticed—she was named one of Forbes' 30 Under 30 in 2020, National Geographic featured her in a major article, and she was named a National Geographic Explorer.

"Next year promises to be another busy one," she says. "The book tour and presentations will continue, and I'm also co-organizing the first-ever City Nature Challenge in Curaçao, a four-day global community science competition encouraging people to document urban biodiversity." The past year—balancing motherhood and launching a book—has been intense, but it has only strengthened her resolve: "Technology can bring nature and people closer together in cities."