GEO-1330 Lecture Notes - Lecture 5: Bottom Trawling, Longline Fishing, Thermohaline Circulation
Document Summary
Directly affect 85% of the earth"s land surface. Have dammed most of the world rivers. Have accelerated extinction rates to 100-1000 times their previous rate (now 1 species per 20 minutes) Now have 8 times the biomass of all other land vertebrates combined (domesticated animals have 20 times their biomass) Have created machines that now require more carbon every year than the human population does. Have a population that could double in 50 years. Unsustainable use of resources (threatening future generations) Fragmentation of habits and loss of remote wilderness. The amount of fish caught (landings) per unit of work expended. Net 10-25 miles wide scrape of the bottom. Line can be miles long and have thousands of hooks since 1960s. Usually die before they are thrown back in. 8-25% of fish caught globally are bycatch. Fishery- a place where specific species of fish are caught. Collapsed fishery - when fish catch falls below 10% of its historic high.
