Testing preconceptions Connecting concepts and “Big” ideas

Where does most of the mass in this piece of wood come from? 1. Air 2. Soil 3. Water 4. Nutrients dissolved in water

Where does most of the mass in this piece of wood come from? 1. Air 2. Soil 3. Water 4. Nutrients dissolved in water

What is the basic molecule from which this mass is derived? 1.N 2 2.O 2 3. CO 2 4. H 2 O

What is the basic molecule from which this mass is derived? 1.N 2 2.O 2 3. CO 2 4. H 2 O

Answer to Q1 provided prior to Q2 Answer to Q1 NOT provided prior to Q2

Photosynthesis – part of a big idea, a spanning idea THE PERSPECTIVE OF AN ECOLOGIST Psynth Carbon from Air Plant physiology Cell biology Chemistry Anatomy Energy and Ecosystems Carbon Fixation Net Primary productivity Joining biological and abiological Energy flow Nutrient cycles Human impacts Limiting factors Feedbacks

Starch Cellulose

Calvin Cycle – light independent RuBP3PG G3P CARBOX REDUCT REGEN ATP NADPH ATP NADP+ ADP Carbon CO2 RUBISCO ADP

Temperature and Enzyme Activity Activity for the two is not on the same scale

Psynth & Patterns of Primary Productivity kgC/m 2 -yr

54.1 Energy & Nutrient dynamics Primary production Secondary production energy flow Psynth and CO2 fixation

Atmosphere Green plants Consumers Detritus Detritivores microbes Fossil fuel Ocean Sediments The Carbon Cycle photosynthesis respiration

Energy/biomass transfer Food chain--system level Trophic efficiency is the percentage of production (energy) transferred from one trophic level to the next to form new biomass Trophic efficiency (%) 14% 29% 4.6% Florida Bog

billion metric tonnes! billion Human Alterations to Global Carbon Dynamics