Chapter 3 Ecosystems and Energy

What is Ecology? Ecology – study of the interactions among organisms and between organisms (biotic) and their abiotic environment.

What is Ecology? Levels of Biological Organization

What is Ecology? Ecological Levels of Organization: Population

What is Ecology? Ecological Levels of Organization: Community

What is Ecology? Ecological Levels of Organization: CO2 Ecosystem

What is Ecology? Landscape – encompasses larger area and several ecosystems Biosphere – the area where all life exists

The Energy of Life Potential vs. Kinetic Energy

The Energy of Life Thermodynamics –

The Energy of Life 1st Law of Thermodynamics – energy can change forms, but is not created or destroyed 2nd Law of Thermodynamics – “Entropy Rules!” amount of usable energy decreases as energy changes forms 1st Law deals with quantity of energy, 2nd Law with quality of energy.

The Energy of Life Photosynthesis 6 CO2 + 12 H2O + radiant energy C6H12O6 + 6 H2O + 6 O2

The Energy of Life Cellular Respiration C6H12O6 + 6 O2 6 CO2 + 6 H2O + energy

The Energy of Life Case-in-Point: Life Without the Sun

The Flow of Energy Through Ecosystems Producers, Consumers, and Decomposers

The Path of Energy Flow Food Chains –

Food Webs –

The Path of Energy Flow Case-in-Point: How Humans Have Affected the Antarctic Food Web Baleen whales What would happen if you eliminated krill? Krill Squid Fishes Toothed whales Penguins Seals

The Path of Energy Flow Ecological Pyramids Pyramid of Biomass Pyramid of Numbers

The Path of Energy Flow Ecological Pyramids Pyramid of Energy

The Path of Energy Flow Example: Thermodynamics in Action Temperate forest: Primary producers = 1,500 g / m2 Desert: Primary producers = 100 g / m2 Food webs very complex, more tertiary consumers, some quaternary. Food webs very simple, very few tertiary consumers

The Path of Energy Flow Desert Biomass Pyramid such as . . . 13.5 kg coyote must range ~12 ha to subsist (30 acres). Desert Biomass Pyramid Tertiary consumers = 0.1 g / m2 Tertiary consumers must range over large areas to obtain enough energy to subsist. Secondary consumers = 1.0 g / m2 Primary consumers = 10 g / m2 Primary producers = 100 g / m2

The Path of Energy Flow Temperate Forest Biomass Pyramid 13.5 kg coyote only needs ~1 ha to subsist (2.5 acres). Temperate Forest Biomass Pyramid NOTE: just relative examples, not accurate Tertiary consumers = 1.5 g / m2 Secondary consumers = 15 g / m2 Primary consumers = 150 g / m2 Primary producers = 1,500 g / m2 Also, possibility of quaternary consumers, like bears.

The Path of Energy Flow Ecosystem Productivity = Net Primary Productivity Gross Primary Productivity Plant cellular respiration =

The Path of Energy Flow Ecosystem Productivity