Loss of species destroys ecosystems
“Jena Experiment”: University of Göttingen participates in 15 years of biodiversity research
How serious is the loss of species globally? Are material cycles in an ecosystem with few species changed? In order to find this out, the “Jena Experiment”, one of the largest biodiversity experiments worldwide, started in 2002. Researchers from the University of Göttingen have been participating from the beginning. Due to its breadth, the Jena Experiment was able to prove for the first time that a loss of biodiversity results in negative consequences for many individual components and processes in ecosystems. A 70-page article in Basic and Applied Ecology summarizes the findings up until now.
In their respective projects, the Göttingen researchers dealt in particular with soil organisms and pollinators. A major goal of their investigations was to better understand interrelationships between the above- and belowground system. The results showed that increased diversity of plants results in increased biomass of microorganisms in soil and this closely correlated with increased accumulation of carbon in soil organic matter. Further, they were able to show that decomposer organisms in soil increased aboveground plant productivity. Increased plant diversity also resulted in more stable and more specialized flower visitation by pollinators. Overall, the results document that the loss of diversity of plants is associated with a loss of important functions and services of ecosystems to which both animals above and below the ground essentially contribute.
Within the Jena Experiment, interdisciplinary working groups from Germany, Austria, Switzerland and the Netherlands took around 80,000 measurements. In more than 500 test plots, they planted varying numbers of plant species, from monocultures to mixtures of 60 species. In addition to plants, they also examined all other organisms living in the ecosystem – in and above the ground. Soil scientists also investigated the material cycles for carbon, nitrogen, nitrate, and water over the entire 15-year period. Since the influence of biodiversity is only visible after a delay, certain effects could only be observed after a period of four or five years – and the effects became correspondingly more pronounced over time. Further information can be found online at www.the-jena-experiment.de.
Original publication: W. Weisser et al. Biodiversity effects on ecosystem functioning in a 15-year grassland experiment: patterns, mechanisms, and open questions. Basic and Applied Ecology 2017. Doi: 10.1016/j.baae.2017.06.002.
Prof. Dr. Stefan Scheu
University of Göttingen
Faculty of Biology and Psychology
Animal Ecology Working Group
Phone +49 551 39-25445
Prof. Dr. Teja Tscharntke
University of Göttingen
Faculty of Agrarian Sciences
Phone +49 551 39-9209