Congruent direction but different magnitude of biodiversity response to land-use intensification in space and time.

Land-use intensification is considered a major driver of biodiversity loss. However, most evidence for land-use effects come from comparing biodiversity in areas differing in current land-use intensity. The robustness of such space-for-time substitutions in capturing temporal changes in biodiversity remains unclear. Here we compare spatial and temporal responses of plant and arthropod communities with changes in land-use intensity using 150 time series of 11 years each from German grasslands. We show that land-use intensification across both space and time resulted in a loss of plant and arthropod α- and β-diversity. The direction of biodiversity response, in both space and time, was generally similar, which supports the value of using spatial data to estimate temporal changes in biodiversity following land-use intensification. However, we find a smaller magnitude of response in α- and β-diversity over time, probably because temporal changes in land use were smaller than spatial ones and biodiversity may take several years to respond to changes in land-use intensity. Our research highlights the utility of space-for-time substitution approaches to approximate temporal trends in biodiversity but also calls for more standardized temporal data to capture delayed biodiversity responses and reliably measure the time course of biodiversity change.