Ecosystems: What Are They and How Do They Work? G. Tyler Miller’s Living in the Environment 14th Edition Chapter 4
Ecology Definition of ecology: study of the interactions of living things with each other and with their environment From Greek word “oikos” which means “house” How is this an appropriate word for this field of study?
Levels of organization in Ecology Biosphere Ecosystem Community Population Individual organism
Levels of organization in Ecology • Definition of ecosystem: all of the organisms living in an area together with their physical environment Example: a deciduous forest ecosystem
Components of Ecosystems • Three main structural components of an ecosystem: • Energy • Chemicals- cycled through photosynthesis and cellular respiration • Organisms – • Producers • Consumers • Decomposers Fig. 4-17 p. 67
Levels of organization in Ecology Definition of community: a group of various species that live in the same place and interact with each other Example: A riparian (river) community within a deciduous forest
Levels of organization in Ecology Definition of population: all of the members of the same species that live in the same place at the same time Example: yellow-bellied slider population in a river
Levels of organization in Ecology Definition of species: a group of similar organisms that can breed and produce fertile offspring Example: horse + donkey = mule Why are horses and donkeys not in the same species????
The Earth’s Life-Support Systems • Troposphere • Stratosphere • Hydrosphere • Lithosphere • Biosphere Fig. 4-7 p. 60
Natural Capital: Sustaining Life of Earth • Life depends on three interconnected factors: • One-way flowof energy from Sun • Cycling ofCrucial Elements • Gravity Fig. 4-8 p. 60
Solar Capital: Flow of Energy to and from the Earth Fig. 4-9 p. 61
Ecosystem Factors • Range of tolerance • Abiotic factors • Limiting factors • Biotic factors Fig. 4-13 p. 64
Ecosystem characteristic: Biodiversity • Genetic diversity • Species diversity • Ecological diversity • Functional diversity
Connections: Food Chains and Energy Flow in Ecosystems Fig. 4-18 p. 68 How does the Second Law of Thermodynamics relate to this system?