Chapter 4: Principles of Ecology How Ecosystems Work Assignment: Finish reading chapter 4. Point/Counterpoint, pg 58 Do Study Quiz for Chap. 2
4.2 Ecology: The Study of Natural Systems Ecology is a field of science that seeks to describe relationships between organisms and their chemical and physical environment. Courtesy of the National Park Service
The Biosphere The biosphere is an enormous biological system, spanning the entire planet. The materials within this closed system are recycled over and over in order for life to be sustained. The only outside contribution to the biosphere is sunlight, which provides energy for all living things.
Biomes and Aquatic Life Zones The biosphere consists of distinct regions called biomes and aquatic life zones. Each has its own chemical and physical conditions and unique assemblage of organisms. Humans inhabit all biomes but are most prevalent in those with the mildest climates.
Five Major Types of Biomes Tundra Taiga Temperature deciduous forest Grassland Desert Also 4 types of Aquatic life zones, these are discussed in Chapter 5: Coral reefs Estuaries (mouths of rivers where fresh and salt waters mix) Deep Ocean Continental Shelf
© Photos.com
Courtesy of U.S. Fish & Wildlife Services
© Photos.com
Courtesy of Tim McCabe/NRCS USDA
© Anthony Ricci/ShutterStock, Inc.
What Is An Ecosystem? Ecosystems: biological systems consisting of organisms and their environment. Biotic components Abiotic components
FIGURE 2: The world’s biomes
Range of Tolerance
Algal Bloom © Josh Meyer/ShutterStock, Inc.
FIGURE 05: The cool water flowing out of the bottom of the reservoir created by Glen Canyon Dam has endangered the razorback sucker and several other native fish species © gary718/ShutterStock, Inc. Inset © Ken Lucas/Visuals Unlimited
Food Chains and Food Webs Food and energy flow through food chains that are part of much larger food webs in ecosystems. FIGURE 8: A grazer food chain and a decomposer food chain, showing the connection between the two
FIGURE 7: Simplified grazer food chains
FIGURE 9: A food web
Trophic Levels: 1. 2. 3.
FIGURE 10: Flow of energy and biomass through a food chain
FIGURE 11: Biomass pyramid
FIGURE 12: Comparison of biomass pyramids
FIGURE 13: Nutrient cycle
FIGURE 14: A simplified view of the carbon cycle
FIGURE 15: A simplified view of the nitrogen cycle
The Nitrogen Cycle Humans alter the nitrogen cycle in at least four ways: In the soil or water 1. 2. 3. In the atmosphere 4.
FIGURE S01_1: A solar-aquatic plant Solar aquatic plant by John Todd “EcoMachine” at Sugarbush, VT was first one. A miniartificial ecosystem is set up to process the waste. 1. Raw sewage contains ammonia, pollutant 2. Bacteria in cylinders convert ammonia to ammonium nitrate. Which is a plant nutrient 3. 4. 5. Algae consumes the nitrates, shrimp eat eat the algae. Fish eat the shrimp (also snails eat sludge that settles to bottom, and fish eat snails) FIGURE S01_1: A solar-aquatic plant Courtesy of John Todd, University of Vermont
FIGURE S01_2: Cross-section of Watson Wick Filter