In the last four years, botanists from Brno’s Masaryk University (MUNI), in cooperation with more than 250 scientists from most European countries in a joint project called ReSurveyEurope, have collected the most extensive data set to date to measure the assessment of changes in flora, vegetation and natural habitats across the European continent, confirming that plant diversity in Europe’s forests, wetlands and grasslands is rapidly disappearing.
Experts from Masaryk University have previously been tasked by the European Environment Agency (EEA) to prepare a pan-European analysis of changes in plant diversity and the quality of natural habitats during the last years.
“However, we found that this could not be done due to a lack of data,” explained project leader Milan Chytrý, from the Institute of Botany and Zoology at the MUNI Faculty of Science. “Therefore, we approached hundreds of botanists and plant ecologists from all over Europe with a request to provide data to the database, which we called ReSurveyEurope.”
In 2020, in collaboration with colleagues from universities and research institutes in Vienna, Halle in Germany, and Wageningen in the Netherlands, they began an extensive collection of all available data on plant diversity surveys repeated at the same location at different times.
During these four years, they were able to accumulate data from more than 85,000 locations into the database. On some of them, a complete list of plant species was taken twice with an interval of several years, on others records were made more than once.
“This way today, the database contains more than 450,000 repeated detailed records of plant diversity and is the largest of its kind in the world,” explained database manager Ilona Knollová, also from the MUNI Faculty of Science. The oldest entry in the database is from 1911, and comes from the Swiss Alps.
The European database project met with a huge response across Europe, with colleagues sending datasets from many different habitats and countries. “However, the data came in various formats, so we had to make a great effort to standardise it,” said Knollová.
The data show major changes, for example, in the European hinterland – including the Czech Republic. “Central European and Czech biotopes have changed significantly over time, and unfortunately mostly for the worse,” said Chytrý.
The data show that lowland forests are now denser and shadier than before, and therefore light-loving plant species are disappearing from their undergrowth. Various wetlands and bogs have been drained or dried up and lost their specialised species. In many meadows and pastures, farming was stopped, which led to them becoming overgrown with tall grasses and bushes.
“In general, specialised species bound only to certain biotopes are disappearing from the landscape, and on the contrary, a few species capable of growing in many different biotopes are spreading. Differences are disappearing, monotony is increasing,” said Chytrý.
Some of the biggest negative changes documented by the database affected the sea dune habitat. These were examined in detail by Marta Gaia Sperandii, an Italian botanist who came to Brno for a two-year research visit to analyse the data from the ReSurveyEurope database in detail.
“Huge areas of dunes along European coasts have disappeared due to the construction of hotels and other recreational facilities,” said Sperandii. “However, even those dunes that have survived are changing rapidly. Invasive plant species from all over the world are spreading on them, such as the South African marmoset. These succulents began to be cultivated as ornamental plants in southern Europe, but they often spread to the dunes, overgrowing and completely changing the community of native species.”
The data from the database shows mostly negative trends, nevertheless, its creators are convinced that a detailed knowledge of ongoing changes is the key to being able to stop them in the near future.
