Principles of Ecology: Matter, Energy and Life PDF

11/09/2024 1 Principles of Ecology: Matter, Energy and Life from Principles of Environmental Science: Inquiry and Applications, 3rd ed. William and Mary Ann Cunningham. (New York: McGr...

11/09/2024 1 Principles of Ecology: Matter, Energy and Life from Principles of Environmental Science: Inquiry and Applications, 3rd ed. William and Mary Ann Cunningham. (New York: McGraw-Hill, 2006) 1 Key Terms 2 McGraw-Hill Course Glossary  Acids  Ecosystem  Organic compounds  Atom  Energy  pH  Bases  First law of  Photosynthesis thermodynamics  Biological community  Population  Food web  Biomass  Potential energy  Herbivores  Carbon cycle  Primary producers  Ions  Carnivores  Productivity  Kinetic energy  Cellular respiration  Second law of thermodynamics  Matter  Chemical compounds  Species  Metabolism  Conservation of matter  Tropic level  Molecules  Consumers  Nitrogen cycle  Decomposers  Omnivores  Ecology 2 1  11/09/2024 3 Topics Principles of Matter & Energy The Building Blocks of Earth and Life Sunlight: Energy for Life Energy and Matter and the Environment Biochemical Cycles and Life Processes 3 4 Part 1: Principles of Matter and Energy To understand how ecosystems function, it is important to first know something about how energy and matter behave - in the universe and in living things. It is also important to understand the basic building blocks of life, starting with cells and organisms, and proceeding to communities and populations. 4 2  11/09/2024 5 Ecology  The scientific study of relationships between organisms and their environment  Examines the life histories, distribution, and behavior of individual species, as well as the structure and function of natural systems at the level of populations, communities, ecosystems, and landscapes  Encourages us to think holistically about interconnections that make whole systems more than just the sum of their individual parts  Examines how and why materials cycle between the living and nonliving parts of our environment 5 6 Matter and Energy  Matter and energy are essential constituents of both the universe and living organisms.  Matter - everything that takes up space and has mass  Energy - the capacity to do work 6 3  11/09/2024 7 Potential vs. Kinetic Energy Potential energy - stored energy that is latent but available for use Kinetic energy - the energy contained in moving object 7 8 Energy Quality Low Quality Energy Diffused, dispersed, or low in temperature Difficult to gather and use for productive purposes Example: heat stored in the oceans High Quality Energy Intense, concentrated, or high in temperature Useful in carrying out work Example: high-voltage electrical energy Many of our most common energy sources are low-quality and must be concentrated or transformed into high-quality sources before they are useful to us. 8 4  11/09/2024 9 Conservation of Matter Under ordinary circumstances, matter is neither created nor destroyed. It is recycled endlessly.  Matter is transformed and combined in different ways, but it doesn't disappear. Everything goes somewhere.  The atoms and molecules in your body have passed through many other organisms, over millions of years. 9 Properties of Energy 10 Energy cannot be recycled. Energy is reused, but it is constantly degraded or lost from the system. Most energy used in ecosystems originates as solar energy. Green plants convert some of this energy to chemical energy, which is then converted to heat or kinetic energy by the animal that eats the plant. 10 5  11/09/2024 11 Laws of Thermodynamics First Law of Thermodynamics Energy cannot be created or destroyed, only changed Second Law of Thermodynamics With each successive energy transfer or transformation in a system, less energy is available to do work. Even though the the total amount of energy remains the same, the energy's intensity and usefulness deteriorate. The second law recognizes the principle of entropy, the tendency of all natural systems to move towards a state of increasing disorder. 11 12 The Building Blocks of Earth and Life The basic units of matter are called “elements”, which can’t be subdivided chemically into smaller units. Elements make up molecules and compounds. It is important to understand basic chemistry in order to understand the critical role of chemistry in Environmental Science. 12 6  11/09/2024 13 Atoms, Molecules, and Compounds  Most material substances can exist in three interchangeable states: solid, liquid, or gas.  Element - substance that cannot be broken down into simpler substances by ordinary chemical reactions  Atom - the smallest particle that exhibits the characteristics of an element  Molecule - a combination of two or more atoms  Compound - a molecule made up of two or more kinds of atoms held together by chemical bonds 13 14 Fig. 2.3 14 7  11/09/2024 Periodic Table of the Elements 15 15 Elements and Environmental Science 16 Just four elements - carbon, hydrogen, oxygen, and nitrogen - make up over 96% of the mass of most organisms. 16 8  11/09/2024 17 Chemical Bonding  Ionic Bond - Formed when one atom gives up an electron to another atom.  Covalent Bond - Formed when two or more atoms share electrons.  Energy is needed to break chemical bonds.  Energy is released when bonds are formed. 17 18 Fig. 2.4 18 9  11/09/2024 19 Acids and Bases  Acids are compounds that readily release hydrogen ions (H+) in water.  Bases are substances that readily take up hydrogen ions (H+) and release hydroxide ions (OH-) in solution.  Strength measured by concentration of H+.  pH scale  0-14 19 20 Fig. 2.5 20 10  11/09/2024 Water Molecule 21 21 22 Water: A Unique Compound  Sixty to 70 percent of the weight of living organisms  Medium in which all of life's chemical reactions occur  Good electrical conductor  Highest surface tension of any common, natural liquid  Liquid over a wide temperature range  Expands when it crystallizes, unlike most substances  High heat of vaporization  High specific heat 22 11  11/09/2024 23 23 24 Cells: The Fundamental Units of Life  Microscopic organisms, such as bacteria and protozoa, are composed of single cells.  The human body contains several trillion cells of about two hundred distinct types.  Enzymes – catalysts that speed up the rate of chemical reactions in living systems  Metabolism - all the energy and matter exchanges that occur within a living cell or organism 24 12  11/09/2024 The Electromagnetic Spectrum 25 The wavelengths of visible light drive photosynthesis. 25 26 Photosynthesis 26 13  11/09/2024 27 Light and Dark Reactions of Photosynthesis 27 Energy Exchange in an Ecosystem 28 28 14  11/09/2024 Energy & Matter in the Environment 29 Organism (species) Population Biological Community Ecosystem Biosphere 29 Food Web: Cross-connected Food Chains 30 30 15  11/09/2024 31 31 Energy Pyramid 32 Most energy in most ecosystems is stored in the bodies of primary producers. Only about 10 percent of the energy at one energy level passes to the next highest trophic level. 32 16  11/09/2024 The Water Cycle 33 33 The Carbon Cycle 34 34 17  11/09/2024 The Nitrogen Cycle 35 35 36 Nitrogen Fixation The nodules on the roots of this plant contain bacteria that help convert nitrogen in the soil to a form the plant can utilize. 36 18  11/09/2024 The Phosphorous Cycle 37 37 The Sulfur Cycle 38 38 19