Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Chapter 2 Principles of Ecology

Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Ecology Branch of biology that describes relationships between organisms and their environments Includes study of: –How different animals relate differently to their environments –Role of different organisms in the food web

Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Law of Conservation of Matter Matter can be changed from one form to another, but it cannot be created or destroyed by ordinary physical or chemical processes Holds true in study of ecology Applies to everything that exists

Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Waste Generation Animals: –Most organisms generate little waste, using only materials related to food supply –Waste is recycled through natural processes Humans: –Generate high volume of waste –Disposal difficult; waste can persist indefinitely, and be harmful or toxic

Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Sources of Human Waste Solid human waste Industrial wastes: chemicals, poisonous metallic compounds, acids, other caustic materials that are left over from manufacturing processes Toxic liquids from landfills contaminating groundwater

Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Sources of Human Waste (Cont.) Atmospheric emissions caused by burning Pesticides Leaking petroleum or petroleum products

Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Some Solutions to Human Waste Problem Recycling Using fewer disposable materials Using water treatment plants and installing special equipment in smokestacks

Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Some Solutions to Human Waste Problem (Cont.) Burning combustible portion of solid waste as energy source Using new technologies to trap pollutants that are by-products of burning

Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Energy The ability to do work or to cause changes to occur Flows through systems from areas of greater concentration to lesser concentration (becomes dispersed or unorganized) Flows through entire ecosystems Cannot be recycled, but may be stored for later use

Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Solar Energy Sunlight captured by plants and stored as molecules of sugar and starch When animal eats a plant, energy released from plant cells allows animal to do work, or is stored as fats, proteins, or carbohydrates until needed

Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Solar Energy (Cont.) Upon plant or animal’s death, energy may be: –Stored as fossil fuels (coal or oil deposits) –Given up as heat during decomposition –Transferred to other animals that eat the remains

Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. First Law of Energy Energy cannot be created or destroyed, but it can be converted from one form to another Radiant energy (from sun) Chemical energy (sugars and starches)

Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. First Law of Energy (Cont.) Kinetic energy (motion and movement) Thermal energy (heat from fuels or nutrients) Electrical energy (electricity)

Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. First Law of Energy (Cont.)

Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Second Law of Energy Every time energy is converted from one form to another, some energy is lost in the form of heat

Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Natural Cycles 96% of the material found in living organisms comes from four elements: carbon, hydrogen, oxygen, and nitrogen Over 30 other elements make up remaining 4% of living tissue

Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Natural Cycles (Cont.) Elemental cycle: –Circular flow of elements from living organisms to nonliving matter –Each element that makes up living tissue has own cycle

Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Carbon Most abundant element found in living organisms Makes up framework of molecules found in living tissue Moves readily between living organisms, the atmosphere, the oceans, and soil

Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Carbon (Cont.) CO 2 released into atmosphere by: –Plant and animal respiration –Combustion of fossil fuels (global warming)

Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Carbon Cycle

Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Nitrogen Most abundant element in the atmosphere (80% of air supply) Colorless, odorless gas Cannot be used by plants or animals unless combined with oxygen or other elements

Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Nitrogen (Cont.) Nitrogen compounds used by plants and animals to form protein and other important molecules (DNA, vitamins)

Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Nitrogen Cycle

Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Water One of the most important natural resources Provides living environment to many species of organisms Supports growth of plant/animal life Makes up 50-70% percent of weight of living plants/animals

Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Water (Cont.) Controls body temperature Acts as solvent for nutrients Necessary for survival

Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Water Cycle

Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Food Chain Organization Consists of a sequence of living organisms that eat and are eaten by other organisms within a community Each chain member feeds on lower-ranking members 1. Producer (plant food) 2. Herbivore or primary consumer (plant-eating organism; example: mouse)

Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Food Chain Organization (Cont.) Each chain member feeds on lower-ranking members (cont.) 3. Carnivore or secondary consumer (meat-eating animal; example: coyote) 4. Decomposer (bacteria)

Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Food Webs and Pyramids Food Web – a group of interwoven food chains Food Pyramid – ranking of organisms according to dominance within a food web –Highest ranking members - versatile predators with few natural enemies –Humans are dominant