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Title: Experimental warming weakens positive plant diversity effects on pitfall trap sampled ant diversity.
Abstract Ants are important components of many terrestrial ecosystems because of their high abundance, their central position in food webs, and because they can strongly influence ecosystem properties such as soil aeration, nutrient cycling, and plant community composition. Moreover, ants are also known to respond strongly to changes in environmental and biological conditions. In particular, two major anthropogenic environmental impacts – climate change and the loss of primary producers – may have interactive effects on ant communities. To examine this potential interaction, we quantified pitfall trap sampled ant diversity and activity across a fully factorial experiment manipulating temperature and grassland plant species richness at the Cedar Creek Ecosystem Science Reserve in Minnesota, USA. Consistent with previous arthropod studies, we found a significant increase in sampled ant diversity in plots with higher sown plant species richness, such that plots with the largest number of plant species also had the highest sampled ant diversity. However, the strength of this relationship declined significantly in experimentally warmed subplots, especially when considered for higher aggregated spatial scales of samples. Taken together, these results suggest that the positive effects of plant diversity on sampled ant diversity may be partially undermined under warmer conditions.  more » « less
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Soil organisms
Medium: X
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National Science Foundation
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