Impacts of landscape heterogeneity on ant community composition in soybean fields

The increased cultivation of arable land in North America is dramatically simplifying landscape composition. The intensification of agriculture has been shown to decrease overall biodiversity. The degree of arthropod diversity in agroecosystems is extremely important to consider because it directly pertains to the levels of pesticides used. Increasing the plant diversity within agricultural systems has been proposed as a way to also increase herbivore species richness and therefore predator species richness. However, the degree of diversity within these agroecosystems can also largely depend on surrounding vegetative diversity, degree of isolation from natural areas, and the management practices in a particular agricultural field. This study was designed to test whether or not ant communities within soybean fields shift with varying compositions of surrounding land-use and immediately adjacent edges. Ant (Hymenoptera: Formicidae) communities were used as indicators of diversity since they react quickly to environmental changes, have staying power within an ecosystem, provide many ecosystem services, and are easily captured and identified. Ants were collected using non-baited pitfall traps, hand samples, and sweep net samples from nine full season, no-till soybean fields throughout western Kentucky. The surrounding land use, field edge compositions, and field area and location were analyzed in relation to ant community diversity and activity density in that particular area. Results showed that field characteristics such as area had minimal impact on ant species diversity. However, there were stronger relationships between ant community diversity and field location, edge types, and composition of surrounding land-use.