A study measures the invisible effect of man on nature, a choral work carried out in collaboration with nine Italian universities and coordinated by that of Tartu in Estonia. The key word? “Dark diversity”A new approach that measures the biodiversity that should be there but that is not there
“Dark diversity”: measuring what is not there
There is a part of biodiversity that does not appear in official counts, which escapes the field observations but that should be there. It is the so -called “dark diversity “that is, the set of native plant species that could live in a given ecosystem but which are absent due to the transformations imposed by man.
To reveal the extent of this phenomenon is an international study published in the prestigious magazine Naturethe result of the project Darkdivnetwhich involved over 250 researchers and researchers all over the world.
The balance is alarming: in the territories with a strong anthropic imprint, only one in five native plant manages to survive. Everything else has been canceled, often in a silent and irreversible way.
DarkdivNet: a global scientific alliance (with strong Italian presence)
The project was coordinated by the University of Tartu, Estonia, and saw a significant Italian participation. In fact, fifteen botanists and botanists from nine universities in our country have contributed, including the University of Bologna with Professor Alessandro Chiarucci, member of the Scientific Committee of Darkdivnet. The Italian universities involved are:
- University of Bologna
- University of Parma
- University of L’Aquila
- University of Subria
- University of Catania
- University of Palermo
- University of Cagliari
- University of Basilicata
- Ca ‘Foscari University Venice
A choral work that led to the collection of data on 5,500 sites in 119 world regions, analyzing not only the species present, but also those “Missing” which, in ideal conditions, should be part of the ecosystem.
The human imprint that leaves empty in nature
The research crossed the information on the plant composition of the sites with theHuman footprint indexan indicator that evaluates the pressure level exerted by anthropic activities. This index takes into account factors such as urbanization, housing density, intensive agriculture, construction of roads and infrastructures, pollution.
Where the imprint of man is more marked, the loss of biodiversity potential vegetable is greater. Not only that: the negative effects also spread far from urbanized areas, hitting areas that would seem intact, including natural reserves and parks.
Protected areas: an embankment that works (but is not enough)
In the territories included in protected areasthe situation is definitely better. Here more than a third of the species potentially compatible with the local environment is found on average. In these cases, absences are often due to natural causes, such as the difficulty of dispersion of seeds or biological limits.
However, these territories are also not immune to the effects of external pressure. This is why it is essential not to limit yourself to the protection of the boundaries of natural areas, but consider the entire landscape and environmental context that surrounds them.
A new way of measuring nature
So far, to evaluate the biodiversity of an area, the species present were simply counted. But this method proved to be insufficient. The introduction of the concept of “Dark diversity” Instead, it allows you to estimate the complete ecological potential of an ecosystem, and to understand how much human presence has compromised it.
This approach not only improves the quality of scientific research, but offers a practical tool to plan environmental restoration: if we know which species are missing, we can intervene to reintroduce them and encourage the regeneration of ecosystems.
The challenge of conservation: act on a local and global scale
“This study clearly shows that human activities are significantly compromising biodiversity, and that it is urgent to enhance environmental protection policies”explains Professor Chiarucci of the University of Bologna. “We need a decisive commitment to increase the number and extension of strictly protected areas, where nature can follow its rhythms without interference.”
Professor Chiarucci is also coordinator of the Spoke 4 del National Biodiversity Future Center (NBFC), together with Professor Paolo Rondinini of the University of Rome. This national research center is working to define future scenarios of planning and management of conservation in Italy, with the aim of protecting 30% of the territory by 2030, in line with international commitments.
Protect what is there, recover what is missing
The Darkdivnet study represents a turning point in understanding biodiversity. It shows us not only what nature preserves, but above all what has lost, and that we could still recover. There “Dark diversity” Thus becomes a compass to guide concrete actions, inside and outside the protected areas, towards a more green and more right future for all living beings.