Study on the forest ecosystem before the appearance of Homo sapiens

2023-11-24 Europe was not covered by dense forests during the last warm period

Lüneburg. Ecologist Professor Brigitte Urban from Leuphana University Lüneburg is one of the authors of a study on the forest ecosystem before the appearance of Homo sapiens that has now been published in the renowned scientific journal Science Advances. For their research, the scientists used a vegetation reconstruction method and applied it to pollen finds from all over Europe from the last interglacial period (129,000-116,000 years ago). The results show that, contrary to previous assumptions, the forests in the temperate climate zones of that time were heterogeneous rather than uniformly dense and that grassland and open land were important components of this biome.

The study shows that the ecology of temperate forests needs to be reconsidered. It helps to explain why a large part of Europe's biodiversity depends on open and sparse forests. According to the calculations of the new study, between 50 and 75 percent of the landscape was covered by open or semi-open vegetation. According to the authors, this is most likely due to the large mammals such as horses, bison, aurochs, rhinoceroses and elephants that lived at that time and kept the landscape open. Consequently, the landscapes have been influenced in their structure and composition not only by the climate, but also by natural disturbance factors. The authors are convinced that these natural disturbance regimes play an important role in temperate forests and argue that the temperate forest biome should be redefined in light of their findings.

The study also has important implications for restoration and conservation goals - "If biodiversity is to be promoted, it is important to integrate large animals into ecosystems," says Jens-Christian Svenning from Aarhus University, Denmark, who led the research project.

Professor Vicky Temperton, Head of the Institute of Ecology at Leupana, comments: "This study is of great importance as our current idea of nature is often characterized by the assumption that a dense forest is the most natural state. However, the results of this study from across Europe show that nature (without major human impact) also includes sparse and dense forests, as well as the grassland under and around the sparse forests. We forget that large herbivores have long kept large parts of our landscapes open. This too is part of nature and has important implications for ecological restoration, which is about restoring degraded habitats and mitigating climate change."

The full article can be read here:

www.science.org/doi/10.1126/sciadv.adi9135