Tue, Aug 03, 2021:On Demand
Background/Question/Methods
As the fastest growing land use type, residential landscapes negatively impact biodiversity due to the loss of natural ecosystems, replacement of native plant species with non-native ornamental monocultures, and consequent biological invasions. Rethinking the design of our urban green spaces and residential yards, and challenging the social perception of plant aesthetics, is vital to mitigate these negative impacts. In this study, we aim to quantify biodiversity in mature residential landscapes through diversity partitioning at varying spatial scales. We assessed 242 plots distributed between the front and back yards of 31 properties within 4 neighborhoods in Gainesville, Florida, United States. Within each plot, all existing plant species and their cover were recorded per structural height class which facilitates discrimination between lawn plant species (groundcover plants <0.5m) and non-lawn species (herbaceous plants, shrubs, trees >0.5m). Additionally, homeowners were surveyed to determine perceived species richness in their landscapes. Using a hierarchical sampling design, we compare alpha, beta, and gamma diversity at different spatial scales (e.g., plot, front/back yard, entire yard, entire neighborhood) allowing us to identify patterns in species traits.
Results/Conclusions Field observations suggest lawns have higher alpha diversity and lower beta diversity than non-lawn areas of yards (e.g. landscape beds) at higher spatial scales due to diverse but common natural groundcovers accompanied by individualized landscaping among residential yards. These patterns are supported by the finding that homeowners self-report species diversity based on ornamental landscape plants (intentional, non-lawn plants) and not volunteers, perhaps due to the plant-blindness phenomenon, i.e., biased attention and value attributed to plants based on traits such as size, color, perceived aesthetic, and utility. Our results shed light on how social perception of plant species drives diversity patterns. Understanding these relationships informs efforts to conserve and enhance biodiversity in urban landscapes.
Results/Conclusions Field observations suggest lawns have higher alpha diversity and lower beta diversity than non-lawn areas of yards (e.g. landscape beds) at higher spatial scales due to diverse but common natural groundcovers accompanied by individualized landscaping among residential yards. These patterns are supported by the finding that homeowners self-report species diversity based on ornamental landscape plants (intentional, non-lawn plants) and not volunteers, perhaps due to the plant-blindness phenomenon, i.e., biased attention and value attributed to plants based on traits such as size, color, perceived aesthetic, and utility. Our results shed light on how social perception of plant species drives diversity patterns. Understanding these relationships informs efforts to conserve and enhance biodiversity in urban landscapes.