BLG 144 Lecture Notes - Lecture 24: Benthic Zone, Insecticide, Lignin
Document Summary
Ecosystem multiple communities that live in an area with biotic + abiotic components linked by nutrient and energy flow. All ecosystems have four components linked by flow of energy: primary producers, consumers, decomposers and abiotic environment. Food chain connects tropic level and describes how energy is moving from one tropic level to another. Food web complex tropic interactions in ecosystem (many food webs together) Parasitoids controlled pests used to get rid of troubling ones. Total biomass (mass of all living things) produced each year is greatest at the lowest tropic level. Tropic cascade: top-down control where consumers limit prey causing cascading effects 2-3 links away. Top down process is predator or consumer limit prey. Taxaphene in the arctic insecticide previously used but stopped b/c dangerous. Persists in the environment without breaking down into harmless substances. Pop a persistant organic pollutant that undergoes biomagnification. Any factor (temperature, water, sunlight and nutrients) that limits the rate of photosynthesis.
