BIOL 150 Lecture Notes - Lecture 1: Trophic Cascade, Carbon Cycle, Carboniferous
Document Summary
Ecosystems: combination of living and non living things in an area. Biotic (living) and abiotic (non-living) are linked via ow of nutrients / energy (food webs represent this) Nutrients: types of resources needed to growth maintenance and reproduction. Energy is inefficient: plants are very inef cient of capturing the sun"s energy, conversion of nutrients into biomass by primary producers, energy is often lost through heat in organisms, varies by species, but is always inef cient! Carbon cycle isn"t balanced humans huge resources users (use 24% of total npp) During carboniferous period (360-300 mya) much of the npp was not consumed or decomposed; was buried and later formed fossil fuels (coal, petroleum) Without human intervention, would slowly be released over time as rocks weather; we are digging it up and burning it (releasing co2) at higher rate. Concentration of co2 in atmosphere 30% higher now than any known measure in last. But, it"s the rate of increase that is causing worries.
