Effects of elevated CO2on model calcareous grasslands: community, species, and genotype level responses

摘要

AbstractWe investigated the responses of model calcareous grassland communities to three CO2concentrations: 330, 500, and 660 μL L‐1, The communities were composed of six species,Bromus erectusHudson,Festuca ovinaL.,Prunella vulgarisL.,Prunella grandiflora(L.) Scholler,Hieracium pilosellaL., andTrifolium repensL., that are native to the calcareous grasslands of Europe. Genotypic variation in CO2response was studied inBromus erectusandFestuca ovina.Plants were harvested after c. 126 days of growth. We found that:At the community level, there were marginally significant (0.1≥P>0.05) increases in leaf and litter dry weight with increasing CO2concentration.There were significant differences between species in CO2response, including both negative and positive responses.Prunella vulgarishad a significant negative response;Hieraciunt pilosellaandFestuca ovinahad significant positive responses;Prunella grandiflorahad a marginally significant positive response; andBromus erectusandTrifotium repensdid not have significant responses.There was significant variation among genotypes in the response to elevated CO2inBromus erectus, but not inFestuca ovina.Based on the observed species‐ and genotype‐level variation in CO2response of calcareous grassland plants in this and other studies, we speculate that increasing atmospheric CO2concentrations will alter community structure in calcareous gr