Urban meadows as an alternative to short mown grassland: effects of composition and height on biodiversity

Abstract

There are increasing calls to provide greenspace in urban areas, yet the ecological quality, as well as quantity, of greenspace is important. Short mown grassland designed for recreational use is the dominant form of urban greenspace in temperate regions but requires considerable maintenance and typically provides limited habitat value for most taxa. Alternatives are increasingly proposed, but the biodiversity potential of these is not well understood. In a replicated experiment across six public urban greenspaces, we used nine different perennial meadow plantings to quantify the relative roles of floristic diversity and height of sown meadows on the richness and composition of three taxonomic groups: plants, invertebrates, and soil microbes. We found that all meadow treatments were colonized by plant species not sown in the plots, suggesting that establishing sown meadows does not preclude further locally determined grassland development if management is appropriate. Colonizing species were rarer in taller and more diverse plots, indicating competition may limit invasion rates. Urban meadow treatments contained invertebrate and microbial communities that differed from mown grassland. Invertebrate taxa responded to changes in both height and richness of meadow vegetation, but most orders were more abundant where vegetation height was longer than mown grassland. Order richness also increased in longer vegetation and Coleoptera family richness increased with plant diversity in summer. Microbial community composition seems sensitive to plant species composition at the soil surface (0–10 cm), but in deeper soils (11–20 cm) community variation was most responsive to plant height, with bacteria and fungi responding differently. In addition to improving local residents’ site satisfaction, native perennial meadow plantings can produce biologically diverse grasslands that support richer and more abundant invertebrate communities, and restructured plant, invertebrate, and soil microbial communities compared with short mown grassland. Our results suggest that diversification of urban greenspace by planting urban meadows in place of some mown amenity grassland is likely to generate substantial biodiversity benefits, with a mosaic of meadow types likely to maximize such benefits.

Ecological and economic benefits of low‐intensity urban lawn management

“…Conversely, resistance of turf grasses to weed invasions relies on minimizing disturbance (Radosevich, Holt, & Ghersa, ). Intensive mowing provides has thus been identified as an important contributor to weed invasions in turfgrass production (Busey, ) and planted urban meadows (Norton et al, ). Although some studies report an inconsistent effect of mowing height (Abu‐Dieyeh & Watson, ), instances of low mowing height reducing lawn weeds are rare.…”

“…Currently there is not a large body of work that investigates the effects of urban lawn mowing regime on ecological factors, although publications in this field are growing (e.g. Chollet, Brabant, Tessier, & Jung, ; Lerman et al, ; Norton et al, ). Most studies examine effects of mowing on one factor (e.g.…”

Public attitudes toward biodiversity‐friendly greenspace management in Europe

“…Urban grasslands encompass a wide range of different types, from short-cut and sometimes irrigated lawns with ornamental and recreational functions to less-intensively managed tall-grass meadows (Figure 1; Tables S1 and S2; Rudolph et al, 2017;Sehrt, Bossdorf, Freitag, & Bucharova, 2020). Tall-grass meadows are typically mown once or twice per year in late summer and can provide habitat for native plants and animals (Cilliers et al, 2004;Norton et al, 2019;Watson, Carignan-Guillemette, Turcotte, Maire, & Proulx, 2020). Converting lawns to meadows significantly increases their value for biodiversity (Chollet, Brabant, Tessier, & Jung, 2018;Wastian, Unterweger, & Betz, 2016) and bene-fits ecosystem functions such as pollination or heat regulation (Ignatieva & Hedblom, 2018).…”

CityScapeLab Berlin: A Research Platform for Untangling Urbanization Effects on Biodiversity

“…Grassland is an important component of urban greenspaces in cities globally [53][54][55][56][57][58];…”