Por Redaccion 
A study involving the University of Oviedo reveals that the diversity of plants in a territory is negatively affected by the human footprint index and its geographical surroundings up to several hundred kilometers. The study has recently been published in the journal Nature, as reported by the University of Oviedo.
The research, in which the Vegetation and Biodiversity Laboratory of the University of Oviedo participated, associated with the Joint Research Unit on Biodiversity in Mieres (University of Oviedo-CSIC-Principado de Asturias) and the Atlantic Botanic Garden of Gijón, was carried out within the framework of the international network DarkDivNet and focused on about 5500 locations in 119 regions worldwide.
They worked with a concept coined in 2011 by researchers at the University of Tartu, the ‘dark diversity’, which is the proportion of species that could live in a specific place but do not.
In each location studied, research teams analyzed all plant species present in different habitats to identify the ‘dark diversity’. This novel methodology for biodiversity studies has allowed estimating the potential plant diversity of each study location and comparing it with the plants actually present.
The results reveal an effect of human activities on biodiversity that was previously unknown. In regions with little human impact, natural habitats contain on average one-third of potential species, mainly because not all species can naturally disperse throughout the territory.
In contrast, in regions with a strong human impact, habitats tend to include only one-fifth of potential species. Traditional methods of estimating biodiversity, based on counting the number of species present without considering the potential ones, tend to underestimate the real effect of human impact, the authors point out.
The DarkDivNet network started in 2018, based on the original idea of Professor Meelis Pärtel from the University of Tartu, the lead author of the study. Since then, research groups from around the world have joined to sample as many regions of the planet as possible.
This was the case of the scientific team from the Atlantic Botanic Garden of Gijón, formed by the professors from the University of Oviedo Borja Jiménez Alfaro and Eduardo Fernández Pascual, who chose the environment of the Picos de Europa National Park to sample 40 study locations, focusing on the alpine vegetation of the central massif. The work extended over five years and had to overcome the COVID-19 pandemic and political crises in many countries in the network.
The degree of human impact in each region was measured based on the Human Footprint Index, which considers factors such as population density, changes in land use, and infrastructure development.
The authors indicate that the results «are alarming because they show that human disturbances have a much greater impact than initially thought, reaching even protected areas far from the origin of human impact. Pollution, deforestation, overgrazing, or forest fires can exclude plant species from their natural habitats, preventing recolonization.
The researchers also note that «the negative influence of human activity was less pronounced when at least one-third of a region’s area remained well preserved, supporting the global goal of protecting 30% of the planet’s surface.»