Understanding the role of biodiversity in the climate, food, water, energy, transport and health nexus in Europe
We in BIONEXT, a multidisciplinary European research team, conducted a systematic review to understand how biodiversity is interconnected with climate, food, water, energy, transport and health. This interconnectedness is called the biodiversity nexus (figure 1).
Figure 1. The biodiversity nexus demonstrates the diverse, intertwined relationships between people and nature. It shows how our resource use affects nature and biodiversity and vice versa.
Method
In the review, we focused on the three-way nexus since analyzing a seven-way nexus would require an extensive amount of labour and most likely, literature addressing all seven nexus elements would be non-existent. Thus, we searched for literature on biodiversity and two other nexus elements. For example, we searched literature that addressed the interconnectedness of biodiversity, food and transport. Specific search terms were defined for each of the nexus elements. For biodiversity, the search string included the following words: biodiversity, habitat, species, nature, and ecosystem. For food, the search string included the following words: food, land use, agriculture, crop, farm, food production, and food consumption. Transport was searched using terms: transport, infrastructure, rail, road, ship, automobile, electric vehicle, aviation, cycling, and walk hydropower transport. The search string for nexus included the following words: nexus, interlinkage, interaction, tradeoff, synergy, cross-sectoral, interdependent, and coupled.
The literature search discovered 2633 articles from the Web of Science. These articles were included in the review if they showed a clear link between biodiversity and two other nexus elements as well as information on the direction and magnitude of the interlinkages.
Figure 2. The countries studied in the 194 articles are shown with study counts on the map.
The aim was to have a database with 20 articles for each of the three-way nexus. Hereby, additional searches were needed to find relevant literature and finally, the review results are based on 194 articles. Some three-way nexus interlinkages were more difficult to find in scientific literature due to the research gap, especially the biodiversity nexus around transport and health. The multidisciplinary research team reviewed eligible articles systematically using a common template to extract data on 16 different aspects. In addition, to provide an overview of the nexus interlinkages, an annotated Causal Loop Diagram was drawn for each article.
Figure 3. The information gathered on biodiversity focused on types of ecosystems and species.
Main findings
The review clearly shows the negative influences of the six nexus elements on biodiversity; Changes in land use, habitat fragmentation due to investments in transport and renewable energy, alteration of river flows and river fragmentation, increase in water demand for energy and irrigation, dredging, land degradation, peat extraction, mining, water pollution, eutrophication and brownification, heat and water stress, collision with traffic and wind turbines are examples of negative biodiversity impacts. About half of the found interlinkages were identified as negative influence on biodiversity.
One-third of the interlinkages show positive impacts on biodiversity. For example, agroecological practices, sustainable management of bioenergy cropping systems, integrated management of water landscapes and management of road verge and railway embankments habitats, ecosystem restorations, urban green and blue infrastructures, and dietary change involving reducing meat consumption.
Figure 2. The article’s results summarized.
Key recommendations
The review revealed some avenues for future research. As already mentioned, not much is known about the biodiversity-transport-water nexus. Terrestrial and freshwater ecosystems are much more studied than the marine realm. In addition, to develop holistic policy measures and actions the evidence from nexus should be analysed together with local practitioners and experts. Research is also needed to identify and quantify positive interlinkages between biodiversity and other nexus elements. This is paramount for the development of win-win policies and interventions over several sectors and nexus elements. Moreover, such reviews should be replicated to fulfil the biodiversity nexus database beyond Europe.
