Abstract:

To project arthropod community response to climate change in wheat fields, a field survey of arthropods over the growing season was made in the plots under a factorial combination of two CO₂ (ambient and 500 μL/L) and two temperature (ambient and +2℃) treatments. The survey collected 52 species, 42 families, 10 orders, and 3 classes. Analyses of overall arthropod community showed a significant increase in evenness due to “Elevated CO₂ + Increased temperature” treatment. Elevated CO₂ and increased temperature treatments had varying impacts on species diversity parameters within the wheat growing season. The “Elevated CO₂ + Increased temperature” treatment increased the Shannon-Wiener index slightly during the early growing season, but decreased it later in the season. Species diversity was most similar between the “Elevated CO₂ + Increased temperature” and the “Increased temperature” treatment. The analysis of arthropod communities by trophic level showed that the “Elevated CO₂” increased herbivorous insect richness and the “Increased temperature” increased parasitoid abundances, compared with the control. The treatments did not affect detritivorous and predaceous arthropod communities. The results of this study suggest that elevated CO₂ and increased temperature can affect arthropod diversity in wheat fields, and the effects may vary between both elevated CO₂ and increased temperature and individual elevation of either CO₂ and temperature.

Key words: phytophagous insect diversity, carnivorous arthropod diversity, FACE, increased temperature, climate change