Data from: Low-intensity agricultural landscapes in Transylvania support high butterfly diversity: implications for conservation

European farmland biodiversity is declining due to land use changes
towards agricultural intensification or abandonment. Some Eastern European
farming systems have sustained traditional forms of use, resulting in high
levels of biodiversity. However, global markets and international policies
now imply rapid and major changes to these systems. To effectively protect
farmland biodiversity, understanding landscape features which underpin
species diversity is crucial. Focusing on butterflies, we addressed this
question for a cultural-historic landscape in Southern Transylvania,
Romania. Following a natural experiment, we randomly selected 120 survey
sites in farmland, 60 each in grassland and arable land. We surveyed
butterfly species richness and abundance by walking transects with four
repeats in summer 2012. We analysed species composition using Detrended
Correspondence Analysis. We modelled species richness, richness of
functional groups, and abundance of selected species in response to
topography, woody vegetation cover and heterogeneity at three spatial
scales, using generalised linear mixed effects models. Species composition
widely overlapped in grassland and arable land. Composition changed along
gradients of heterogeneity at local and context scales, and of woody
vegetation cover at context and landscape scales. The effect of local
heterogeneity on species richness was positive in arable land, but
negative in grassland. Plant species richness, and structural and
topographic conditions at multiple scales explained species richness,
richness of functional groups and species abundances. Our study revealed
high conservation value of both grassland and arable land in low-intensity
Eastern European farmland. Besides grassland, also heterogeneous arable
land provides important habitat for butterflies. While butterfly diversity
in arable land benefits from heterogeneity by small-scale structures,
grasslands should be protected from fragmentation to provide sufficiently
large areas for butterflies. These findings have important implications
for EU agricultural and conservation policy. Most importantly,
conservation management needs to consider entire landscapes, and implement
appropriate measures at multiple spatial scales.

Data from: Low-intensity
agricultural landscapes in Transylvania support high butterfly diversity:
implications for conservationSpecies abundance and
environmental data from Loos et al. 2014Loos et al 2014
Butterflies.xls