•Exam #2 F 3/5 in class (bring cheat sheet)•Review Th-3/4 from 5-7pm in PAI 3.02

Not all habitats are equal

How do stable ecosystems develop?

Primary Succession- the first organisms to colonize bare rock

Secondary Succession- recovery from a disturbance

Primary Succession- from non-living to living

Primary succession as this glacier retreats

Fig 54.22

Primary Successionafter glacier retreat,150-300 years

Fig 54.22

in Primary Succession biodiversity increases as resources become available

Fig 54.22

Primary Succession: each stage helps enable the next

Fig54.23

Secondary Succession: after a fire

Fig 54.21

Grassland biodiversity and biomass are increased by regular burns

Secondary Succession of a field(20 yrs)

Disturbances can increase resources, but disturb the interconnections between organisms

Human vs Natural Disturbances

Chernobyl fireApril 26, 1986

See this video for some additional info about Chernobyl:http://video.google.com/videoplay?docid=1108163171078608385

The Chernobyl accident was by far the largest unintentional release of radioactive material into the environment and caused widespread contamination in Europe.

After the accident on April 26, 1986, ~116,000 people were evacuated, most from a zone of 30-km radius. That included about 45,000 people from the town of Pripyat.

The most heavily exposed emergency workers received doses that were sufficiently high to kill them in the weeks and months after the accident.

Chernobyl April 26, 1986

Cancer consequences of the Chernobyl accident: 20 years on J. Radiological Protection26 (2006) 127–140Elisabeth Cardis et al.

Mitosis

Cancer: Cell Division Gone Wrong

Multiple mutations are required for a single cell to become cancerous.

The rapidity of increased childhood thyroid cancer in the heavily contaminated areas of Belarus, Ukraine and Russia was surprising.

4 years

The issue of the effects on health of the Chernobyl accident has become part of the political debate over the future role of nuclear energy, which has inevitably led to dispute over the level of effects either observed or anticipated.

After the accident on April 26, 1986, ~116,000 people were evacuated, most from a zone of 30-km radius. That included about 45,000 people from the town of Pripyat.

Another video about what has happened since the accident:

http://www.vbs.tv/watch/the-vice-guide-to-travel/the-radioactive-beasts-of-chernobyl

For more pictures: http://www.nikongear.com/Chernobyl/Chernobyl_1.htm

What about non-human inhabitants?

turtle in exclusion zone

•Exam #2 F 3/5 in class (bring cheat sheet)•Review Th-3/4 from 5-7pm in PAI 3.02