Hintergrundbild mit Feldern

Plant diversity, plant history, and soil history effects on the temporal dynamics of plant and soil activity

Principle Investigators: Prof. Dr. Nico Eisenhauer, Leipzig; Dr. Jes Hines, Leipzig; Prof. Dr. Christian Wirth, Leipzig

One major underlying reason why relationships between biodiversity and ecosystem functioning strengthen over time may be that species respond to the presence of competitors by differentiating into dissimilar niches, which allows diverse communities to maximize resource use and minimize competition. In theory, such niche differences include temporal variation in biological activity, but the seasonality (phenology) and development of plant temporal niches and potential linkages to soil biological activity patterns have rarely been quantified in BEF experiments. Long-term monitoring has shown that biological activity of communities is shifting, and such changes in phenology are generally associated with global changes in abiotic environmental drivers. We propose that the attribution of phenological shifts to abiotic factors alone may be premature, and measuring above-belowground phenology of important processes (e.g., plant growth and decomposition) will allow us to quantify the role of temporal niche partitioning in plant diversity-ecosystem function relationships. Our experiments testing the influence of plant diversity on plant and soil biological phenology could provide a powerful link between biodiversity, abiotic environment, and drivers of biological rates across trophic levels above and below the ground. In this subproject, we designed three coordinated work packages to test mechanisms driving potential shifts in activity periods. We start by testing whether aboveground and belowground activity periods are linked to the effects of plant diversity on abiotic conditions (WP1). If so, are activity periods dependent upon longer-term selection effects of plant diversity on soils (WP2), or are activity periods more strongly associated with plant traits and plant history, and their interaction with soil history (WP3).  By exploring the influence of plant diversity, plant history, and soil history on the onset, magnitude, duration, and stability of activity patterns, we test whether these factors drive temporal niche differentiation and strengthen over time due to plant history and soil history effects. If true, an important implication is that novel communities without shared interaction history could be a poor surrogate for conservation of biodiversity and ecosystem functioning in the long-term.