Ecology David Mellor, PhD Citizen Science Coordinator Virginia Master Naturalists

Overview of Ecology Definition and Scope Energy and Food Webs Nutrient Cycles Population Dynamics Ecological Interactions Community Structure Ecosystem Services Human Impacts

Overview of Ecology Definition and Scope Energy and Food Webs Nutrient Cycles Population Dynamics Ecological Interactions Community Structure Ecosystem Services Human Impacts

Scope of Biology Biosphere Ecosystem Community Population Organism Organ System Organ Tissue Cell Organelle Molecules

Scope of Ecology Biosphere Ecosystem Community Population Organism Organ System Organ Tissue Cell Organelle Molecules

Scope of Ecology Biosphere – Where life exists on Earth Ecosystem – The group of interacting living communities and non-living factors in one area Community – The group of interacting organisms in one area Population – A group of organisms of one species Organism – An individual living being

Scope of Ecology Biosphere – Where life exists on Earth Ecosystem – The group of interacting living communities and non-living factors in one area Community – The group of interacting organisms in one area Population – A group of organisms of one species Organism – An individual living being

Scope of Ecology Biosphere – Where life exists on Earth Ecosystem – The group of interacting living communities and non-living factors in one area Community – The group of interacting organisms in one area Population – A group of organisms of one species Organism – An individual living being

Scope of Ecology Biosphere – Where life exists on Earth Ecosystem – The group of interacting living communities and non-living factors in one area Community – The group of interacting organisms in one area Population – A group of organisms of one species Organism – An individual living being

Scope of Ecology Biosphere – Where life exists on Earth Ecosystem – The group of interacting living communities and non-living factors in one area Community – The group of interacting organisms in one area Population – A group of organisms of one species Organism – An individual living being

Questions Think about a nearby natural area and describe: 1)The ecosystem 2)The community 3)A few of the populations of organisms that live in that area Realizing that you do not know everything about that area, what steps would you take to learn more about it?

Energy and Food Webs

Trophic levels are a classification of species based on their main source of nutrition Trophic levels: – Primary producers – Primary consumers – Secondary consumers – Tertiary consumers – Decomposers – Omnivores

Primary Producers Tertiary consumers Secondary consumers Primary consumers

Primary Producers Tertiary consumers Secondary consumers Primary consumers Decomposers Omnivore

Primary Producers

Primary Consumers

Secondary Consumers

Tertiary Consumers

Omnivores

Decomposers

Photosynthesis H 2 O + CO 2 + energy  C 6 H 12 O 6 + O 2 H 2 O + CO 2 + energy  + O 2

This molecule can be used for: 1)Building block 2)Energy i.Growth* ii.Maintenance* iii.Metabolism* iv.Reproduction* * inefficient! Glucose/Sugars

Respiration C 6 H 12 O 6 + O 2  H 2 O + CO 2 + energy + O 2  H 2 O + CO 2 + energy

Questions While thinking about energy and resource use, describe why eating “lower on the food chain” is more environmentally friendly. What new information surprised you most in the previous lecture? Why was this information new to you?