The main impact of pesticides on ecosystems includes the disruption of food webs and the decline of non-target species, such as pollinators and beneficial insects. Pesticides can reduce biodiversity and lead to biomagnification in predator species, affecting their health and survival. Additionally, runoff from agricultural fields can contaminate waterways, harming aquatic life and disrupting ecosystem services. Over time, this can cause imbalances in ecosystems, leading to decreased resilience and productivity, ultimately affecting human food security and environmental health.