Ch. 5

a. What are the different trophic categories/levels in a food chain/web? How do you expect bioavailable contaminants to move in a food chain?

b. What are the main differences between terrestrial, aquatic, and detrital food webs/pyramids?

c. Why are terrestrial trophic levels not as efficient as those found in aquatic systems? How many trophic levels do most ecosystems support?

d. Discuss ecosystem disturbances.

e. What is ecological succession and what are the types? What role does fire/other disturbances play in succession?

f. What are biomes? Be able to identify different biomes and what factors control where they occur. Which biomes are the most productive and why?

g. Know climatic, general elevation and distance from the equator trends.

h. What do we call small regions in the environment where the climate differs from the overall climate?

i. Define a tipping point.

j. What is the millennium ecosystem assessment and what were its findings?


k. What is the typical way of measuring biome and aquatic system productivity?

aquatic is upside down whereas the others are normal triangles

typically 3-4 levels and terrestrial have low ecological efficiency

  1. Primary: area lacking plants and soils is initially invaded by plants when soil forms
  1. Secondary: area cleared by fire, human activity or flooding and then left alone, is reinvaded by plants and animals from other ecosystems
  1. Aquatic: soil particles eroded from land or plant detritus build up in ponds or lakes, eventually filling them

• Succession: transition of one biotic community to another
Fire and Succession • Some pine species require fire • Resilience: ability of ecosystems to return to normal after disturbance • Tipping Point: situation in human impacted ecosystem where small action catalyzes major change in system state

Biome: large geographical biotic community

Feed level defined by primary source of energy (green plants first) top quaternary consumer -> tertiary consumer -> secondary consumer -> primary consumer -> primary producer bottom

microclimates

situation in human impacted ecosystem where small action catalyzes major change in system state

4 year project involving 1400 scientists produced reports on state of earths ecosystem - human activity is putting a strain on the natural functions of the earth and sustainability

oxygen levels