Abstract

Plant diversity, both in species and in functional traits, is a key driver of ecosystem functioning in grasslands, but where and when it matters remains unclear. In this talk, I explore two dimensions that shape our understanding of these relationships: space and time. Across space, root traits offer key insights into the mechanisms linking plant diversity and grassland productivity, and these links appear to be strongly contingent on climate. Yet spatial patterns alone are hard to disentangle, because diversity and productivity influence each other through complex feedback loops. Time may hold the key to this long-standing puzzle. Intra-annual observations can reveal the temporal ordering of effects, but longer time series are needed to trace how these effects unfold over years. At ESIIL, I bring both dimensions together, using far longer, globally distributed time series from the Nutrient Network to resolve the order, lag, and direction of diversity–productivity feedbacks, and to test how drought reshapes them. This moves our understanding from static snapshots toward the dynamic processes that govern grassland responses to a changing climate.

Speaker Bio

Karl Andraczek is an ecologist who uses trait-based approaches and causal inference to study how plant diversity shapes ecosystem functioning, above and below ground. He is motivated by finding nature-based solutions to climate extremes such as drought. He received his PhD in Ecology from the University of Leipzig and was a postdoc at the German Centre for Integrative Biodiversity Research (iDiv), where he led an independent project on how belowground traits confer climate resilience to grasslands. At CU Boulder, he is keen to collaborate on climate resilience, biodiversity–ecosystem functioning feedbacks, and trait ecology.