BISC 102 Lecture Notes - Lecture 24: Ecosystem Ecology, Nutrient Cycle, Food Web
Document Summary
Environmental toxicology = study of negative impacts of chemicals on living organisms. Ex/ pesticides bees, estrogen waste in water fish changing sex, lead pipes unsafe drinking water. Estuary = partly enclosed body of water long coast where freshwater and salt water meets. Ecosystem = all organisms living in a community as well as all the abiotic factors with which they interact. Ecosystem ecology emphasizes question about energy flow and nutrient cycle. Breaks down remains from all trophic level: abiotic environment. Energy flows enters as light and lost as heat. Nutrients cycle can move through abiotic environment (never used up) Food web describes complex feeding relationships within an ecosystem. Organism can function at more than one trophic level. Solar energy enters (about half absorbed or reflected by atmosphere) much absorbed or reflected by non-photosynthetic surfaces only small % reaches primary producers small portion converted to chemical energy.