A butterfly zoo is probably the last thing you’d expect to find on the grounds of a steel plant. But that’s exactly what you’ll find under the trees at ArcelorMittal Tubarão in Brazil – and it’s just one of the ways we’re raising awareness of how we can responsibly use and contribute to nature while making steel.


For the last 28 years, ArcelorMittal Tubarão has been planting trees to create a green belt around the steel plant as a more environmental way of controlling emissions, investing US $1,750,000 between 2010 and 2017 alone. With 2.6m trees now covering 50% of the 13.5m square meter site, the company has created a live natural barrier containing diverse species of plants and animals. Its trees, bushes and lagoons make an ideal habitat for birds, insects, reptiles and small animals.

This also contributes to the well-being of people working and living in and around the plant – it’s pleasant to look at, absorbs noise and holds heat. But its main purpose is to act as a wind break to control dust emissions from the plant. So, in order to justify their efforts, over the last 20 years the team at Tubarão has commissioned several studies into the effectiveness of the green belt.

Proof of purpose

The latest studies – in 2010 and 2014 – were carried out by the Midwest Research Institute (MRI Global), an American government institution. Using advanced computational modelling, researchers looked at whether the green belt was indeed as effective as a wind fence. They found that, in the four years between studies, the growth in density and height of the green belt had made it even better than man-made wind fences at controlling dust emissions. In just four years, the tree growth had reduced wind in the coal yard by 93% and the wind affecting coal being moved around the site by 47%.

The team have used the research findings to strategically cultivate the green belt, and are also working with a local organisation, the Instituto Capixaba de Pesquisa, Assistência Técnica e Extensão Rural (INCAPER), to find the most effective planting techniques to enhance the area’s rich biodiversity. 

An attractive habitat

In addition to its primary purpose, the green belt is benefiting the local ecosystem. It reduces soil erosion around the plant and is home to 161 bird species, 11 mammal species and 382 types of flora. The green belt lagoons have become an important refuge for around 350 endangered caimans – and we’re working with a local environmental institute to monitor this precious community.

We also run an educational programme (Programa Conhecer) for residents, schools and employees’ families through our Environmental Education Centre. This includes monitored tours through the vegetation and butterfly zoo, as well as educational talks on the steel industry and our sustainable and innovative ways of working. Over 20,000 people have visited the site through this program, which is creating valuable relationships with the wider community – and trust in ArcelorMittal as a responsible user of land, one of our 10 sustainable development outcomes.

“We have a wide variety of flora and fauna species living in harmony with urban and industrial activities in the plant. Our focus is to preserve the living conditions of these species, contributing to their study through continuous monitoring.”

Fernanda Passamani – biologist in Espirito Santo