The Abundance and Biodiversity of Arthropods in Biofuel Crops: Insects and Arachnids in Corn, Switchgrass and Native Mixed Grass Prairie Fields.

摘要

Concerns about fossil fuel prices and harmful effects have prompted research and investment in biofuel development. Biofuels have the potential to provide a stable fuel source that reduces carbon emissions. However, the ecological impacts of different crop choices should be examined. Arthropod communities in corn and switchgrass monocultures and mixed grass prairie polycultures were examined to determine the impact of the crop choice on the arthropod communities. Results show that, when compared to corn and switchgrass fields, mixed grass prairie fields had higher values for arthropod biomass, number, size, the number of orders present, the number of individuals in each order, and the overall arthropod diversity. Corn fields were dominated by Diptera (61.83%) and contained very low abundance of the other orders found in this study. Mixed grass prairie fields also showed Diptera as the most prevalent order (43.47%), followed by Hemiptera (17.89%) and Homoptera (13.65%), Hymenoptera (6.12%), Coleoptera (5.61%), with the others each less than 2.5%, Thysanoptera, Acari, Araneae, Lepidoptera, Orthoptera and Odonata. Switchgrass fields showed arthropod communities with diversity levels between that of corn and mixed grass prairies, with Diptera (39.33%), Coleoptera (17.91%) and Hemiptera (16.33%) dominating the community. Hymenoptera 5.53% and Lepidoptera, Odonata, Orthoptera, Thysanoptera, Acari and Araneae total 17%. Average arthropod abundance was 49.33 individuals and 98 milligrams in mixed grass prairie fields, 35.59 individuals and 49 milligrams in switchgrass fields, and only 23.93 individuals and 23 milligrams in corn fields. The average number of orders found was also correlated to field type, with 4.17 in corn fields, 5.53 in switchgrass fields, and 7.08 in mixed grass prairie fields. It is concluded that transitioning from planting fields with corn to growing mixed grass prairie, or switchgrass, for cellulosic ethanol and biodiesel production would increase the overall abundance and biodiversity of the arthropod community.