Can flower strips combined with hedges improve biodiversity in intensively used agricultural areas? This is what a team from the University of Würzburg is investigating with project partners from four EU countries.
The problem is well known: Worldwide, the quantity and diversity of insects are declining. The populations of many bird species have also shrunk drastically in recent decades. The reasons for this have been well researched. On the one hand, scientists attribute this decline to changes in land use, for example the increase in large monocultures such as corn and rapeseed. On the other hand, they also cite climate change with increased heat and long periods of drought as a cause.
Whether biodiversity in intensively used agricultural areas can be preserved and so-called “ecosystem services” maximized with comparatively simple measures: That is what an international collaborative project will be investigating over the next three years. Eight project partners from four EU countries are involved, and the project is being led by the University of Rennes in France. The Julius-Maximilians-Universität Würzburg (JMU) is also involved in the project and will receive around 200,000 euros from the German Federal Ministry of Education and Research.
Field experiments in Lower Franconia
“We are investigating whether hedges in combination with flower strips adjacent to agricultural land can help increase biodiversity without reducing agricultural yields,” says Dr. Sarah Redlich, explaining the approach. Redlich is a researcher at the Department of Zoology III (headed by Prof. Ingolf Steffan-Dewenter) at JMU; for many years, the biologist has been conducting research on the decline in biodiversity and the influence of land use, climate and management on ecosystem services in agricultural systems.
In 20 landscapes in Lower Franconia, she and her team will soon plant flowering strips that are in close proximity to hedgerows and wheat fields. “Hedges are usually beneficial for the biodiversity of different animals, for example birds,” Redlich explains. But at the same time, they can also provide shelter and protection for agricultural pests. This is something farmers don’t appreciate at all.
The biologist’s hope is that flowering strips will reduce what she calls “the potential disadvantages of hedges.” Apart from wildlife and pollinators, predatory or seed-eating insects also benefit from the structural diversity and resources in hedgerows and flower strips. If they spillover from there into the neighboring field, they could thus protect it from pest infestations and weeds and, in the best case, even enable the reduction of pesticides.
Living labs and citizen-based data collection
An important focus of the ConservES research project is the establishment of a living lab in the Lower Franconia region. The living lab offers the possibility of a transdisciplinary exchange between scientists and non-scientific stakeholders from the region to jointly define the direction of the research project and to implement the field experiments.
So-called “BioBlitzes” are another central component and involve citizen-based data collection on site. ” On a weekend in June and supervised by taxonomic experts, we want to invite interested citizens to record the baseline diversity before the flower strips are established – in other words, investigate which and how many arthropods, birds and plants already live in the respective area,” says the biologist. Combined with detailed biodiversity surveys by the scientists and a second BioBlitz in the final year of the project, the changes in biodiversity can thus be precisely documented.
The other project participants will proceed identically – in five different regions of Europe, which differ primarily in their respective climates. These range from the rather mild Atlantic climate in western and northern France, through Wallonia (Belgium) and southern Germany, to the continental climate in the western Czech Republic. This makes it possible to include the effect of temperature, and thus an important driver of climate change, in the study, Redlich explains.
Involvement of farmers
Farmers will also be closely involved in the research, both through the living lab, the BioBlitz and field experiments. “Involving local farmers is one of the most important activities and a crucial factor for the success of the project,” says Stephanie Timm, project manager at the German German Agricultural Society (DLG), which is responsible for international communication and for disseminating the results and knowledge gained.
“The concept of the living lab is to work with farmers to develop scenarios for expanding diversity within, near and around fields to optimize agroecosystem diversity at the farm and landscape level. Farmers will be involved in biodiversity conservation and ecosystem health,” Timm said.
In the end, project participants expect “high ecological benefits of floral enrichment for biodiversity and ecosystem services on conventionally farmed land,” according to project leader Joan Van Baaren of the University of Rennes.
The Department of Zoology III
The Department of Zoology III at the University of Würzburg has a long-standing international reputation in global change research. In the search for the causes of regional and global declines in biodiversity, research into the ecology, evolution, behavior and physiology of insects is a major focus of the work of Chair Professor Ingolf Steffan-Dewenter and his team.
Previous research by members of the department suggests that agricultural land use is one of the causes of recent insect declines. In other publications, they have been able to show the interactions between climate and land use on plant, animal and microbial diversity. Their work underscores the importance of species richness for pollination success and pest control.
