02499nas a2200205 4500008004100000245009700041210006900138300001300207490000800220520184800228653000902076653002402085653002302109653002102132653002402153100001702177700001702194700001602211856006602227 2013 eng d00aGenetic diversity of a dominant C4 grass is altered with increased precipitation variability0 aGenetic diversity of a dominant C4 grass is altered with increas a571 -5810 v1713 a
Climate change has the potential to alter the genetic diversity of plant populations with consequences for community dynamics and ecosystem processes. Recent research focused on changes in climatic means has found evidence of decreased precipitation amounts reducing genetic diversity. However, increased variability in climatic regimes is also predicted with climate change, but the effects of this aspect of climate change on genetic diversity have yet to be investigated. After 10 years of experimentally increased intra-annual variability in growing season precipitation regimes, we report that the number of genotypes of the dominant C4 grass, Andropogon gerardii Vitman, has been significantly reduced in native tallgrass prairie compared with unmanipulated prairie. However, individuals showed a different pattern of genomic similarity with increased precipitation variability resulting in greater genome dissimilarity among individuals when compared to unmanipulated prairie. Further, we found that genomic dissimilarity was positively correlated with aboveground productivity in this system. The increased genomic dissimilarity among individuals in the altered treatment alongside evidence for a positive correlation of genomic dissimilarity with phenotypic variation suggests ecological sorting of genotypes may be occurring via niche differentiation. Overall, we found effects of more variable precipitation regimes on population-level genetic diversity were complex, emphasizing the need to look beyond genotype numbers for understanding the impacts of climate change on genetic diversity. Recognition that future climate change may alter aspects of genetic diversity in different ways suggests possible mechanisms by which plant populations may be able to retain a diversity of traits in the face of declining biodiversity.
10aAFLP10aAndropogon gerardii10aDice dissimilarity10adominant species10aGenotypic structure1 aAvolio, M.L.1 aBeaulieu, J.1 aSmith, M.D. uhttps://link.springer.com/article/10.1007%2Fs00442-012-2427-4