BIOS1301 Lecture Notes - Lecture 2: Ecosystem Services, Anthropocene, Exponential Growth
14 Jun 2018
School
Department
Course
Professor
LECTURE 2
Case study 1: Land clearing in Australia
• ENVIRONMENTAL ISSUE
o clearing of woodland areas
o impacts on ecosystem services (soil erosion, carbon credits) and biodiversity
• EFFECT ON ENVIRONMENT
o destruction of habitat for large range of animals (mammals, birds, reptiles,
invertebrates) and also vegetation communities
• ROLE OF ENV SCIENCE
o measure extent of land clearing
o estimate impacts on biodiversity
o map different vegetation using satellite imagery
• POLICY AND MANAGEMENT
o legislation, regulation and codes
o Australian Government role in relation to the State Government roles
EXTINCTION
• Anthropocene- 6th extinction event
• birds- mostly due to harvesting, 20% extinction caused by humans
• Spix's Macaw (Brazil) extinct in wild in 2000
• fish- global fish catch increase six times between 1950 and 1997
• Loss of biodiversity since 1970: freshwater (lost 35%), marine (lost 25%), terrestrial (lost
24%), total (lost 30%)
ISNT EXTINCTION NATURAL ANYWAY?
• between 1,000x greater extinction rate currently than the background rate (fossil record)
• projected future rate is up to 10,000x the background rate (fossil record)
BIOSIVERSITY LOSS- WHY WORRY?
• biodiversity contributes by providing, regulating ecosystems for the benefit of humans (ie
ecosystem services) e.g. loss of soils with erosion due to land clearing
• biodiversity loss is implicated in direct impacts on human societies, usually poor societies
• utilitarian values (medicines-> many have come from the natural world, pollination (our
vegetables are pollinated by insects), water and air quality (environment provides))
HUMAN IMPACTS
• Affecting the environment at all levels of ecological organisation
o Individuals
o Populations
o Communities
o Ecosystems
o Biosphere
WORLD POPULATION GROWTH
• 2025-> 8.2 billion ????
find more resources at oneclass.com
find more resources at oneclass.com
Document Summary
Extinction: anthropocene- 6th extinction event, birds- mostly due to harvesting, 20% extinction caused by humans, spix"s macaw (brazil) extinct in wild in 2000 fish- global fish catch increase six times between 1950 and 1997. Loss of biodiversity since 1970: freshwater (lost 35%), marine (lost 25%), terrestrial (lost. Isnt extinction natural anyway: between 1,000x greater extinction rate currently than the background rate (fossil record, projected future rate is up to 10,000x the background rate (fossil record) Human impacts: affecting the environment at all levels of ecological organisation. The gap between the birth and death rate is whts important. Exponential growth rate is slowing: main driver -> women"s education and family size. As women become educated they can say no in these patriarchal societies where there were considerable power by men (particularly men who could have polygamous relatioonships) Diet: humans have a unique, broad and expanding food niche. ranges from carnivory to obligate herbivory.
