Summary
Ecosystems operate through a complex interplay of energy flow and nutrient cycling. Primary producers harness energy from nonliving sources, initiating food chains that transmit energy through consumers with substantial losses at each trophic level. Nutrients like carbon, nitrogen, and phosphorus continuously cycle among living organisms and their environment. Human activities, including fertilizer application and fossil fuel combustion, can disrupt these natural cycles, leading to phenomena such as eutrophication and climate change. Understanding these processes is vital for managing ecosystems sustainably.