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 Ecology Test VII


Bio-geochemical Cycles 
Quiz I

Problem set I

Ecology Test 
Test 1   Test 2
Test 3   Test 4
Test 5   Test 6
Test 7   Test 8
Test 9   M/C 

Energy Calculation 
Quiz 1   Quiz 2

Human Ecology  
Quiz 1   Quiz 2
Quiz 3   

Population Dynamics 
Quiz 1   Quiz 2
Quiz 3   Quiz 4
Quiz 5   Quiz 6

Part A: The Thames River

1. In the Thames river, the following organisms were found: crayfish, algae (a single-celled plant), clodophera (a long stringy plant), colpodium (a single-celled animal), caddis fly larvae, little fast black thingies, nymphs, minnows, and three types of fungus.

a) Sketch a likely food pyramid. Label it with the names of the organisms.
b) The total amount of energy made by the plants was found to be 1,000,000 kJ. Account for all the kJ (i.e. where and how much energy is transferred to each other organism?
c) For each organism, sketch a likely population graph for the next 10 years. Label the graph with numbers.
d) Where on the food pyramid are the r-selecting organisms? Where are the K-selecting ones?
e) List in order which organisms are most susceptible to abiotic fluctuations. What personal evidence do you have for your conclusion?
f) How do the Laws of Thermodynamics apply to the our studies in the Thames ?

2. The population of African fur seals is increasing at a rate of 9 percent per year. The population as of 1995 is currently at 10,000,000. 
a) In what year will the population be 20,000,000? Show your work.
b) When was the population 2.5 million? Show your work.
c) What will the population be in 32 years? SYW.
d) When will the population be 24,000,000? SYW.

3. You have been given 4 empty buckets. If you were to leave the classroom to go get 4 things containing nitrogen* atoms,...
a) What 4 things or substances would you bring back?
b) Name the processes by which those atoms "move" from being in one substance to the next. *NOTE: You may choose either the carbon, nitrogen, oxygen, phosphorous or sulphur cycle for this question.

4. In a certain section of the river, fifty crayfish were caught in the Thames and their shells were labelled with indelible laundry markers. Two weeks later, 40 crayfish were caught. Of those 40, 16 were labelled with the marker. 
a) What was the original population?
b) What values (results) would you expect if you re-sampled the population next month?
c) Sketch a graph showing a population which exhibits:
d) classic sigmoidal growth with a carrying capacity of 1000.
e) classic J curve growth, grossly exceeding it's carrying capacity of 10,0000,000

Part B: Thinkers - the Big Picture

1. What sort of field techniques did we do in the Thames which would have been used in order to build and desgin the Lateblight model? Pick two methods, decribe them , give some dummy data, and say how that technique would be used in the case of designing Lateblight.

a) Pick a problem from chapter 28 or use a Homer-Dixon one. Describe 3 reasons why that problem exists. (Don't describe the problem, describe the reasons why the problem exists).For one of those underlying reasons, explain:
b) two field survey techniques which could help.
c) two broad principle from using Lotus Modelling could help.
d) two broad principles from using Lateblight could help.
e) two pieces of factual information from chapter 26 could help.
f) two pieces of factual information from chapter 27 could help.
As a possible starting point you might start off by saying, "One of the underlying causes of ..... is ..... If people were more aware of ..... then instead of .... they would ...."