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Structure of course

Environmental variabilityOrganisms

EcosystemsPopulations

Species interactionsCommunities

Applied Ecological Issues

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Outline for ecosystems

Introduction

How does energy move through an ecosystem?

How does matter move through an ecosystem?

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How does matter move through an ecosystem?

Matter = elements

e.g., what are ways that a carbon atom movesfrom one compartment of an ecosystem to another?

How fast do carbon atoms move from one compartment to another?

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How does a carbon atom move through an ecosystem?

A few examples:

-erosion

-rock formation

-transport by organisms-photosynthesis-respiration-consumption by heterotrophs

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Organisms move elements through chemical transformations

organic C inorganic C

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Figure 7.1

inorganicinorganic

organic organic

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Memory tools

Oxidation – Olé- oxidation loses energy- oxidized loses electrons

Reduction – requires energy- reduced receives electrons

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Figure 7.2

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How does matter move through an ecosystem?

Cycles between inorganic and organic forms andbetween different compartments of ecosystems

Difference between matter and energy movement?

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Figure 7.3

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Cycles of matter

watercarbonnitrogenphosphorussulfur

Focus on important pools and transfers

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Water cycle

Figure 7.4

14Figure 7.5 Carbon cycle

C cycle

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Figure 7.6

Biological transformations of carbon

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Fig. 7.11

N cycle

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Figure 7.11binorganic formsused by plants

e.g., proteins

Biological transformations of nitrogen

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Figure 7.12

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Figure 7.13

P cycle

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Figure 7.14a S cycle

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Figure 7.14b

Biological transformations of sulfur

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What do I expect you to know about element cycles?

- which forms are available to bacteria, plants,and animals

-which pools and transfers are largest

-which transfers are changes in form of theelement

- which transfers are biological transfers vs. chemical or physical transfers

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All organisms participate in element cycling. Each group will be assigned one of the following element cycles (C, N, P, S). Describe 5 ways that your everyday activities contribute to the element cycles (hint: think about the indirect effects of your activities). In your answer, include 1 process that transforms an element from inorganic to organic form, 1 process that transforms an element from organic form to inorganic form, and 1 non-biological transformation.

Work in groups of three

Some groups will be called upon to share their answers