Control Dynamics Of An Algae-Brine Shrimp Ecosystem Lab Report
Investigating the Control Dynamics of an Algae-Brine Shrimp Ecosystem
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Introduction The purpose of this lab is to investigate whether an ecosystem consisting of marine algae and brine shrimp are controlled by top-down or bottom-up mechanisms. The terms top-down and bottom-up in the context of ecology describe which trophic levels are enforcing population pressures on the others. Thus, the top-down mechanism of control holds that consumers are responsible for determining the abundance of a producer, while the bottom-up view holds that producers control the abundance of the consumers in higher trophic levels (Power, 1992). In this simulated ecosystem, we will be working with the marine alga Platymonas sp. and the crustacean Artemia salina, commonly referred to as brine shrimp. The former will serve as the producer and the latter as the consumer. …show more content…
Since we are investigating if this ecosystem operates using top-down controls, we will be varying the number of brine shrimp per jar whilst keeping algae concentration and volume of seawater in each jar constant. There will be three groups of jars with each group containing 3 jars each; group 1 will have one brine shrimp, group 2 will have two brine shrimps, while group 3 will be the control, already filled with the required concentration of algae and containing no brine shrimp. Fill the group 1 and 2 jars with 46.68 mL of seawater and 3.32 mL of algae, taken from the 25,000 cells/mL jar of algae. Be sure to use a micropipette to transfer the required portions of a milliliter of each liquid when needed after setting the required amount, and use a new pipette tip for each new
113437768
Introduction The purpose of this lab is to investigate whether an ecosystem consisting of marine algae and brine shrimp are controlled by top-down or bottom-up mechanisms. The terms top-down and bottom-up in the context of ecology describe which trophic levels are enforcing population pressures on the others. Thus, the top-down mechanism of control holds that consumers are responsible for determining the abundance of a producer, while the bottom-up view holds that producers control the abundance of the consumers in higher trophic levels (Power, 1992). In this simulated ecosystem, we will be working with the marine alga Platymonas sp. and the crustacean Artemia salina, commonly referred to as brine shrimp. The former will serve as the producer and the latter as the consumer. …show more content…
Since we are investigating if this ecosystem operates using top-down controls, we will be varying the number of brine shrimp per jar whilst keeping algae concentration and volume of seawater in each jar constant. There will be three groups of jars with each group containing 3 jars each; group 1 will have one brine shrimp, group 2 will have two brine shrimps, while group 3 will be the control, already filled with the required concentration of algae and containing no brine shrimp. Fill the group 1 and 2 jars with 46.68 mL of seawater and 3.32 mL of algae, taken from the 25,000 cells/mL jar of algae. Be sure to use a micropipette to transfer the required portions of a milliliter of each liquid when needed after setting the required amount, and use a new pipette tip for each new