 Understand that all human societies depend on sustainable ecosystems characterized by maximum biodiversity.  Explain how managing the world’s ecosystems means achieving sustainable use, preventing sudden irreversible changes to ecosystems, and addressing the impact of poverty on society and sustainability.  Describe how habitat change, overexploitation, pollution, invasive species, and climate change influence biodiversity.

Ecosystems…  supply food, fuel, natural resources, & water.  cycle nutrients & decompose wastes.  regulate climate.  pollinate crops & disperse seeds.  provide cultural/recreational opportunities. Sustainable Use: use resources to meet our current needs without compromising the ability of future generations to meet their needs  maintain biodiversity!

Genetic Diversity: differences within a species which keep a population healthy, such as the ability to resist certain diseases or tolerate drought  Lack of this can threaten species’ survival (potential extinction)  Biodiversity also refers to the variety of ecosystems found on Earth (human-made & natural)

 Habitat change: humans alter a habitat so native species can no longer live there  move or die  We clear land for agriculture, forestry, urban development  Ex) Rainforests - only 9 million km 2 are left of the original 16 million km 2

 Bottom Trawling: drag fishing nets along the ocean floor to catch shrimp and bottom- dwelling fish  Removes many producers  Harms coral formations

Overexploitation: use a resource faster than it can be replaced  Since 1950s, humans removed ~90% of large fish from the sea  Atlantic cod have not recovered since the 1990s

 Canada has the world’s largest supply of freshwater  Aral Sea in Central Asia  once 4 th largest freshwater lake in the world, water was diverted for irrigation of crops until it split in two and all commercial fishery industry was lost Good News!! Kazakh government has increased water flow into the lake, and the North Aral Sea level is slowly rising again…

Pollution: any substance added to the environment that produces a condition that is harmful to organisms WaterEnters water…Examples Point Source Pollution At a specific place (identifiable source) - oil spills from tankers - waste water from pulp & paper mills - partly treated waste water from sewage treatment plant Non-point Source Pollution Indirectly when rain/snow travels over land, picking up pollutants from many different sources - fertilizer & pesticide run-off from farms - salt run-off from roads

Invasive species: non-native species that harms the ecosystem into which it has been introduced (from international travel & trade)  Outcompete native species - no natural predators or reproduce faster  Ex) Starlings & sparrows are both invasive species, outcompeted eastern bluebirds for nest sites  bluebird populations have declined by 90%

Climate: average weather conditions in a region over 30+ years Climate Change: average temperatures rise/fall, amount of rainfall rises/falls, general wind directions may change Global Warming: increase in Earth’s average temperature, caused partly by an increase in CO 2 in the atmosphere (from burning of fossil fuels) Drives climate change

1. What is the difference between habitat change and habitat fragmentation? 2. Name an invasive species in Ontario, and explain how this species has affected native species. 3. Ecosystems provide things that directly affect you. Do you take these things for granted? Give an example of how an ecosystem specifically helps you.