Importance of meteorological and land use parameters for insect diversity in agricultural landscapes

Abstract

Human-induced climate and land-use changes are important factors influencing global insect diversity. Nevertheless, the influence of weather on biodiversity is still relatively rarely studied. Grassland insects may be the taxon that is most affected by changing weather. We focused on the influence of weather and land-use management on butterflies in hayed meadows in the Czech Republic. During two consecutive years (2019–2020), we studied nearly 300 independent meadows. The abundance of butterflies was more influenced by the weather than their species richness. We observed positive and mainly linear effects of increasing vegetation temperatures. One very influential variable was the light intensity, which had a nonlinear effect that promoted butterflies under direct sunlight. The humidity had mainly moderate, nonlinear effects. Surprisingly, the wind had only a small effect. We observed important effects of the flowering intensity and vegetation height on the butterfly species richness and abundance regarding land use. Marginal woody vegetation cover had a positive effect on the butterfly abundance, and management had little effect. We concluded that weather and land use had important effects on butterflies. Based on our research, we recommended the reconsideration of scientific studies and monitoring programs for insects concerning the temperature threshold (≥ 25 °C) and the consideration of light intensity as an important factor. Applying a detailed approach to measuring the flowering intensity is likely unnecessary, while meadow land-use parameters appear to be necessary for insect populations.