To understand the environment, we need to know how energy and matter behave in the environment and in living things Matter, Energy and Life Building blocks of the Environment

Anything that takes up space and has mass Atoms are the smallest particles that are characteristic of an Element Matter is made up of different elements a carbon atom Matter

Most matter can exist in three interchangeable states: as a solid, a liquid, or a gas Elements are substances that cannot be broken down into simpler substances by ordinary chemical reactions The Periodic Table of Elements shows all known elements organized by their properties

Periodic Table of Elements The table is organized by similarity in atomic structure and characteristics

Conservation of Matter Under ordinary circumstances, matter is neither created nor destroyed. It is recycled endlessly. Where did the elements come from? The phrase ‘we’re all stardust’ is true!

Just four elements – carbon, hydrogen, oxygen, and nitrogen - make up over 96% of the mass of most organisms.

Chemical reactions, the breaking and forming of molecular bonds, create the simple and complex compounds and substances on which life depends. Elements are joined by chemical bonds to form molecules or compounds Reactants Products C + O 2 CO 2 + energy carbon + oxygen carbon dioxide + energy black colorless colorless gas solidgas

Examples of molecules H 2 + ½ O 2 H 2 O

Water is a unique compound Water: - is the medium in which all of life’s chemical reactions occur - is a good electrical conductor - has the highest surface tension of any common, natural liquid - is a liquid over a wide temperature range - expands when it crystallizes, unlike most substances

The capacity to do work heat, light, electricity, and chemical energy are all types of energy Energy can be: Kinetic energy -- contained in moving objects or: Potential energy – stored energy (physical, chemical or nuclear) Energy

Food has chemical energy: calories

High-quality energy is concentrated This is very useful for doing work Examples: Hot fire, high voltage electricity, boiling water Low-quality energy is diffused or dispersed This is not very useful for doing work A lake contains a lot of heat energy even if its cold, but that heat energy is not very useful because it’s not concentrated Low-quality energy sources must be transformed to high-quality sources to be very useful

Two Fundamental Principles of Energy: Energy is conserved—it is neither created nor destroyed but may be transferred or transformed (First law of thermodynamics) However, with each successive transfer or transformation of energy, there is less energy available to do work because it is dissipated and disorder is increased (Entropy increases ! (tendency of all natural systems to move towards a state of increasing disorder) - Second law of thermodynamics).

Organisms are highly organized and require energy to maintain that organization—they must fight entropy! With every activity a cell or an organism performs, some energy is lost or dissipated

Organism (species) Population Biological Community Ecosystem Biosphere (ecosphere)

Food Web: Cross-connected Food Chains (Cunningham & Cunningham 2002)

Simplified Antarctic Food Web (Miller 2002)

(Enger & Smith 2002)

Cycle of Matter and Energy between the main Structural Components of an Ecosystem (Miller 2002)

Organisms in an ecosystem may be identified by how they obtain their food. (Miller 2002)

Quantification terms for Biological material Biomass – estimate of the total mass, or amount, of living material Productivity – the amount of biomass produced in a given area during a given period of time

Pyramid of Energy Flow (Miller 2002)

Pyramid of Organism Numbers? (Miller 2002)

Pyramid of Organism Biomass? (Miller 2002)

Community-level Interactions (Botkin & Keller 2003)

Key Points: 1.Matter and Energy are the fundamental building blocks of the environment and organisms. 2.The periodic table of elements shows all the known elements organized by atomic structure and chemical properties. 3.Matter is made of elements that can combine to form molecules and compounds by chemical reactions. 4.Matter and energy are conserved, but with each successive reaction, energy is dissipated. 5.Potential energy is stored energy; Kinetic energy is a release of energy by moving matter. 6.Life requires matter and energy—photosynthesis captures solar energy to create life; respiration releases that stored energy

Key Points: 7.An ecosystem is an environment interacting with a biological community that is composed of populations which are composed of individual organisms. 8.Primary producers fix energy and nutrients needed by consumers. 9.A food chain or web (a connection of food chains by some common organism(s)) is a sequence of organisms in which energy and materials pass from one trophic level to another. 10. An organism’s feeding position in an ecosystem is it’s tropic level.

Key Points: 11. Organisms in an ecosystem may be classified by: how they obtain their food, their consumer level or their tropic level. 12.Generally the transfer of energy in an ecosystem from one tropic level to another is accompanied by roughly a 90% loss.