Bio 104 6/5/96

The last day of class! Ecosystems: interactions between communities and the abiotic environment

all communities depend on the process of photosynthesis
responsible for the energy of a community

Primary producers: plants in both land and water

carry on photosynthesis

Consumers eat primary producers
Terrestrial Level of Consumption:

          plants-->primary producers
          eaten by herbivores-->primary consumers
          eaten by carnivores-->secondary consumers
          eaten by tertiary or quarternary consumers

Aquatic Level of consumption:

          phytoplankton-->primary producers
          zooplankton-->primary consumers
          small fish-->secondary consumers
          bigger fish-->tertiary consumers
          shark-->quarternary consumers

Food web: way that organisms interact with on another

detritovores are the decayers, break down food

Energy pyramid:

          producers:  10,000 Kcal
          primary consumers attain 1000 Kcal
          secondary consumers attain 100 Kcal
          tertiary consumers attain 10 Kcal

takes 10,000 Kcal of primary production to support one tertiary or quarternary consumer

SEE SIDELIGHT FIGURE 22.1

Energy loss from livestock production. Figure 22.1 SEE FIGURE 22.11 (C)

Ecological pyramids. Figure 22.11

further up the food chain the more energy
the higher you go up the more primary production it takes to support upper levels
you lose 10 times the amount of Kcal per trophic level
process of photosynthesis will stop if any of the required elements are not present
1. sunlight
2. CO2
3. Water
4. nitrogen: in order to make proteins

Carbon Cycle: SEE FIGURE 22.4

The carbon cycle. Figure 22.4 Basically by cellular respiration, burning of fossil fuels, and decomposing, we return carbon to the cycle. Nitrogen Cycle: SEE FIGURE 22.5

The nitrogen cycle. Figure 22.5

atmospheric nitrogen 78% but has three high energy bonds
3 triple bonds cannot be utilized in this form
bacteria fixes nitrogen in soil and roots
it is needed to make chlorophyll, etc..
In death, we release nitrogen into the soil, which is converted to ammonia and eventually forms soil nitrate
denitrifying bacteria release nitrogen into the atmosphere; completing the cycle

Nitrogen fixing plants belong to the legumes
Biomagnification:

DDT concentration throughout the food chain
DDT in water .000003 ppm

DDT in zooplankton .04 ppm

DDT in small fish
stored .5 ppm

DDT in large fish 2 ppm

DDT in fish eating birds 25 ppm

DDT concentration throughout the food chain
DDT in water	.000003 ppm
DDT in zooplankton	.04 ppm
DDT in small fish stored	.5 ppm
DDT in large fish	2 ppm
DDT in fish eating birds	25 ppm

Well I have finished the notes for this class. Thank-you for all your patience while waiting for these notes. Turkey don't shoot the dog, just smile.

Jeff

Well, I have just finished the web pages for this class. I hope you enjoyed the new format. Thank you for all of your suggestions in the survey, I will try and implement some of them if I do this for future classes. Good luck on the exam, I guess I should start studying now...

Bryan

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