The many sides of biodiversity
Biodiversity starts at home. Awareness of the issue is on the rise among cities and local governments, which face the challenge of managing a wide range of different habitats. They also have a tremendous opportunity to make such spaces more attractive for bees and other organisms. A look at three German cities and what they are doing.
Losheim am See
Measuring approximately 97 square kilometers, the municipality of Losheim am See lies nestled in the Saar-Hunsrück Nature Park. Its lake, various excellent hiking trails, and picturesque setting in the Schwarzwälder Hochwald natural area – with vast mixed beech forests, idyllic valleys, and streams – make Losheim am See a popular tourist destination. The parks and green spaces team from the municipal facilities management office works hand in hand with the city’s department of environmental and municipal development to take care of the recreational areas, parks, and other green spaces along the lake, as well as curb strips, street trees, and cemeteries. The team also keeps Losheim am See’s network of hiking trails and bike paths in shape. Two forest rangers and a team of foresters are responsible for the city’s forests and wooded areas. Werner Ludwig, the head of the municipal department of environmental and municipal development, has a clear picture of his priorities regarding the maintenance and management of the wide range of natural habitats in the city: “As a city, we have to lead by example when it comes to preserving and fostering biodiversity in our municipal habitats. That is why the environmental management, forestry, and facilities management teams always work hand in hand to find practical, feasible solutions.”
»Our goal is to combine efficient management and care with protecting natural habitats.«Werner LudwigHead of the municipal department of environmental and municipal development in Losheim am See
Sustainable park and open-space management has long been a passion for the people of Pirmasens, the southwestern German city on seven hills. This commitment has already earned it the Spar-Euro prize for money-saving solutions and the StadtGrün naturnah seal for eco-friendly open-space management. The city oversees more than 100 hectares of parks, playgrounds, and sports fields – and caring for those spaces costs money. To keep these costs to a minimum while ensuring an appealing natural environment, the city has taken a host of measures that have allowed it to save some 100,000 euros a year in staffing and energy expenses. As part of its own biodiversity strategy, Pirmasens is constantly breathing new life into its open-space and park management concept. Representatives from conservation and environmental organizations, schools and kindergartens, employees of the city’s parks and cemeteries department, local politicians, and active citizens have all come together to take part in a dedicated working group. Thomas Iraschko, head of the city’s business and services division, explains: “Transforming public spaces in line with nature-focused concepts is always associated with a new way of thinking in government, policy, and the general public. In Pirmasens, we have succeeded in putting together a ‘green package’ that allows us to encourage steps toward sustainability, thanks in no small part to the close cooperation between municipal institutions and citizens.”
Located deep in the south of Germany, Waiblingen is part of a vibrant metropolitan area and is an important hub of industry. Major traffic arteries such as the B 14 and B 29 national highways, along with public transit links, help keep the county seat of the Rems-Murr administrative district connected within the greater Stuttgart region. Surrounded by hillside vineyards, the city stretches along the Rems river. With once-pervasive native species such as partridges and lapwings now all but gone, the city of Waiblingen has developed its own biodiversity strategy to preserve the habitats of local animal and plant species in the interest of enhancing quality of life in the area. For years now, the municipal government has been working with local nature conservation organizations to foster biodiversity. Their campaigns range from setting aside open spaces for wildflowers and creating biotopes to handing out free seeds, restoring dry stone walls in hillside vineyards, and organizing the Naturnaher Garten competition to promote a more natural approach to gardening. In 2019, the Remstal-Gartenschau became Germany’s first multicity gardening exhibition to connect 16 towns and cities along the Rems river and raised public awareness of biodiversity in the process. Jörg Kist from Waiblingen’s department of parks and open spaces says: “Protecting habitats is a never-ending task. As a result, we continue to systematically pursue our biodiversity strategy through projects at schools and kindergartens, such as our week-long campaigns to let children experience nature hands-on and our efforts to set up school gardens. That way, we can raise awareness of nature among kids and encourage their interest.”
Forestry expert Professor Jörg Müller examines biodiversity, forest ecology, and natural conservation as part of his research work. Müller is the deputy director of the Bavarian Forest National Park, where he is in charge of the conservation and research department. He also heads the Department of Animal Ecology and Tropical Biology at the University of Würzburg.
Professor Müller, your research examines topics such as protecting biodiversity in our forests. Why is biodiversity so important?
MÜLLER The diversity of ecosystems, species, and genes has been important to our existence since the dawn of humanity. Even the earliest human settlements were in regions with a wide variety of habitats such as pastures and rivers, which provided food and drinking water. To this day, at least half of the products in a grocery store, for example, are based on various mycological enzymes that account for the wide range of foods available to us. Or think of medicines – a particularly pertinent topic during our current pandemic. We deprive ourselves of the foundations of life when we lose certain things. You can quantify that too and calculate the pollination output of wild bees in euros, for example. But I’m not a fan of breaking everything down into monetary costs.
Where are we seeing a loss of biodiversity, and how is it manifesting itself?
MÜLLER There’s no simple answer to that question. It also depends on which indicators you look at. Apex predators have never had it as good as they do right now. There are more wolves and lynxes in Germany today than ever before in the past 100 years, for example. If you look at forests, however, a wave of extinction already set in 100 to 150 years ago with the advent of commercial forestry. That may have made sense at the time, seeing as how wood was scarce and there was a need to raise productivity in the space of just a few decades. But certain woodboring beetles have become rarer as a result. Luckily, a lot has changed for the better in the past 30 years thanks to a shift in attitudes. On the other hand, the situation in agriculture and construction has grown more serious in many respects. We’re sealing too much soil, plain and simple. Legal regulation aimed at compensating for soil sealing is an opportunity to do something about that. The use of pesticides has also increased significantly in the past 30 years, which robs many species of their habitats and hurts their chances of survival.
Is targeted intervention in nature always detrimental, and is it better to just let things take their course?
MÜLLER There isn’t a right or wrong answer here either. What matters is allowing nature to take its course in certain situations and continuously asking ourselves where we need to take a hands-off approach. Restraint is always the answer when nature is highly active on its own in current ecosystems. The best example of that is the Bavarian Forest National Park. Our decision ten years ago to “sacrifice” the forest to the bark beetle, as some put it, and simply let things take their course was an unpopular one. Today we know that it was an absolute win in terms of biodiversity. But there are times when the opposite happens. A deciduous forest that has been homogenized by humans, for instance, exhibits practically no natural activity anymore. There isn’t much going on there in terms of structural diversity. That’s when active intervention is definitely beneficial for biodiversity.
In a brochure on using chainsaws in conservation that you and seven other co-authors wrote, you offer practical tips for creating and fostering the growth of such structure and habitats in managed forests. What do people need to keep in mind here?
MÜLLER Using chainsaws in conservation may seem like a contradiction at first. But, in fact, nature is behind many events in forests that damage trees. Branches break off, lightning strikes, storms knock down trees — all of these adverse events foster diversity. For example, a tree might suffer a gash that attracts fungus that in turn attracts rare beetles. You can use tools to recreate many of these adverse events. It doesn’t matter to the species whether it was due to human intervention or lightning. We can use that to our advantage and enrich middle-aged forests that are structurally poor by creating deadwood, thinning out tree crowns, and much more.
Is it possible to transfer your findings from forestry to other areas? What is the situation when it comes to biodiversity in cities?
MÜLLER What makes urban parks and green spaces so appealing is that they aren’t used commercially. They don’t have to produce corn or wood. That is indeed something special, since it means that the trees and bushes aren’t subject to the pressure of timber production. It’s one of the reasons why a park in the center of Regensburg, Germany, has more ancient species of beetles than any of the area’s managed forests — simply because the trees there are allowed to grow old and receive regular care so that they remain safe for people to walk past. As I said, care-oriented intervention like this has the potential to create diverse structures and make such spaces an attractive second habitat. Cities are often very interested in supporting this kind of approach.
Can an urban environment replace a natural habitat?
MÜLLER What’s interesting is that species aren’t terribly particular. They aren’t tied down to a specific structure. Ultimately, they don’t care where the structure is and how they get there. Take the peregrine falcon, for example, which perches in church towers in urban environments, despite it being fully unnatural for them. In the end, we should be happy that many species learn to use our man-made objects and live with us, seeing as how we modern humans have destroyed so many natural habitats.