Dynamics on vegetation, pollinators and soil microorganisms after transforming boreal urban lawns into meadows

Source abstract

Allowing lawns to grow into meadows has been described as a simple way to support biodiversity in the urban environment, also reducing the carbon footprint of lawn management. Experimental studies demonstrating such benefits in boreal region cities are, however, scarce. We investigated boreal lawns, which were transformed into urban meadows by volunteers who overturned the existing soil and sowed wildflower seeds. We followed changes in vegetation, pollinators and soil microbial communities as well as in soil physicochemical properties before and two years after the transformations. During this period, vegetation species richness and diversity increased in the new meadows, unlike in control lawns, and provided habitat and foraging resources for 35 species of bees and other insects. However, none of the soil physicochemical properties, phospholipid fatty acid-based soil microorganism communities nor bacterial or fungal biomasses from meadow soils were significantly different from those found under nearby lawn soils. This study illustrates the potential that simple and inexpensive transformative actions can have on the enhancement of aboveground biodiversity in the current urban lawnscape. The results also show that any changes in soil properties take longer to respond to changes in aboveground vegetation communities and management.