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Mon. Tues. Wed. Thurs. Fri.Week ofOct. 6

Week ofOct. 13

No labs – Fall Break

Week ofOct. 20

Wet, muddy outdoor lab – wear closed-toed shoes

Week ofOct. 27

Independent project set-up

Class in LibraryMultimedia Room

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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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Organisms move elements through chemical transformations

organic C inorganic C

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Figure 7.1

inorganicinorganic

organic organic

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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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Figure 7.4

Water cycle

11Figure 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 7.11be.g., proteins inorganic forms

used by plants

Biological transformations of nitrogen

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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 transfers are changes in form of theelement

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

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How does matter move through an ecosystem?

Nutrient recycling in terrestrial andaquatic ecosystems

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Nutrient recycling in terrestrial systems

- where is it happening?

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Nutrient recycling in terrestrial systems

- new weathering of bedrock provides small amount of nutrients taken up by vegetation each year (~10%)

- how do we know that?

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-mass balance

-inputs = outputs

-weathering + precipitation =loss in streams

measurecalculate by difference

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Organic matter decomposition

1. Leaching of soluble compounds by water

2. Consumption by detritus-feeding orgs.- e.g., earthworms, millipedes, etc.

3. Breakdown of rest by fungi and bacteria- how do they decompose?

What factors affect rate of decomposition?

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Effect of rainfall on rate of leaf decomposition

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Litter/living leaf

Soil P/plant P

Soil N/plant N

%of total org C

Tropical Temperate

Which column is larger?

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Land use affects phosphorus retention in a system

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Nitrogen fixation can increase nitrogen avail.

Litter quality (nitrogen content) of different tree species

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Mychorrhizae increase nutrient content ofplants

Fig. 8.7