Welcome Grant from National Science Foundation: Fire, Atmospheric pCO 2, and Climate as Alternative Primary Controls of C 4 -Grass Abundance: The Late-Quaternary Perspective Overall Goals Build on core ecosystem concepts through current research Develop a framework for engaging students in critical thinking and active learning about ecology Provide dynamic educational tools, lesson ideas, and online resources Build bridges between science educators, scientists, and students Schedule Day 1: Ecosystems (Present) Day 2: Paleo-ecology (Past) Day 3: Climate Change (Future)

“The past is a key to the future”

Last 50 years Last 650,000 years 0 650,000 Images from IPCC Last 12,000 years 012,000 History of atmospheric CO 2 concentrations

“The past is a key to the future” Characterize processes that occur over tens to thousands of years Baseline information; variability Identify phenomena outside our range of experience (e.g. novel communities, rapid changes) Responses to environmental change Testing models used to predict future changes Primary succession in habitat with no history of plants or soil

What are ecosystems? Ecological systems All of the organisms (plants, animals, microbes) and the abiotic (sun, soil) environment with which they interact Community + physical & chemical environment These factors vary over space & time They provide goods & services (clean air, food, habitat)

Examples of ecosystems

Ecosystem properties Structure Diversity (species richness, evenness) Species composition (relative abundance) Soil type Function Productivity Decomposition Carbon uptake Nitrogen cycling

Ecosystem structure: latitudinal gradients in diversity

Ecosystem function: Net Primary Production (blue = water green = land) % area X NPP/area = % of total NPP

Biodiversity influences ecosystem function Cedar Creek Ecosystem Science Reserve, Minnesota Biomass (post/pre drought) Pre-drought species richness Tilman and Downing

Ecosystem Function Elements/Nutrients Cycle : Carbon Nitrogen Oxygen Phosphorus Energy Flows: sun   producers  consumers  decomposers

Energy flow : food & trophic relationships Producers (autotrophs) Consumers (heterotrophs)

Food energy available to humans

Carbon cycle Buried carbonate 60,000

Biome: a major type of terrestrial community categorized by its dominant plant form, seasonality of leaves, leaf morphology, latitude.

Geography of biomes

Geography of grass-dominated biomes Jacobs et al

Importance of grasslands

in C 3 plants RUBISCO also binds with O 2, especially at high temperatures (photorespiration) Calvin Benson cycle Photosynthetic pathways

Controls of biome distributions and ecosystem processes