COMPOSITIONAL AND DEMOGRAPHIC RESPONSE OF ANT AND PLANT COMMUNITIES TO GLYPHOSATE USAGE: THE FATE OF A CLOSED POPULATION

ABSTRACT

Glyphosate-based herbicides (GBH) are widely used in agroecosystems, raising concerns about their impact on non-target insects. Ants, being widely distributed and sensitive to environmental changes, serve as indicators of ecosystem health. However, limited research exists on the medium and long-term effects of herbicide exposure on ant populations. This study investigates the response of ants and plant communities in a semi-enclosed lawn to GBH spray over a fourmonth period. Ants were collected using pitfall traps, while plant cover percentages were estimated using belt transects. After a baseline data collection in the first month, GBH was applied. Pre-spray, plant cover was 10.75%, followed by successive surveys indicating a rapid recovery with cover estimates of 0.84%, 10.19%, 45.35%, and 72.69%. In contrast, the ant community experienced a decline in median species richness across all pitfall traps from 6.00 ± 2.42 prior to the spray to 5.25 ± 1.63, 5.00 ± 1.73, and 3.00 ± 0.92 in subsequent surveys. Similarly, median Shannon_H indices of the ants decreased from 1.16 ± 0.27 and 1.21 ± 0.20 in the first and second month to 0.89 ± 0.30 and 0.81 ± 0.30 in the subsequent months. This study underscores the need for careful consideration and re-evaluation of herbicide usage in agroecosystems to minimize unintended consequences and preserve the integrity of ecosystems.