ENV201H5 Lecture Notes - Lecture 10: Food Miles, Primary Production, Carcinogen
Document Summary
Agriculture major way in which we have globally altered the. Agriculture produces/consumes energy (oil & gas energy), produces environment wastes/pollution. Agricultural sector major contributor to ghg emissions. We"ve made major alterations to global environment. Apples (ancient) were naturally found in china --> wild/ancestor of current apples. Today apples are grown in many areas --> thus, geographic distribution is very different. Non-food sources (plants/animals) geographic distribution has changed (clearing lands for pasture lands, removing weeds) Have modified the food species genetically --> selecting for sweeter, Wheat: wild wheat --> current wheat : selectively breed so visible parts redder apples become much larger. Humans have replaced the top of the food chain. Through agricultural practices, we have significantly altered biogeochemical cycles. Net primary productivity (pp) today associated with agricultural crops. Agriculture is about harnessing energy flowing through systems. Last 150 years: shift in type/amount of energy inputted into our food system.
