Ecosystem Ecology, ESPM 111

• Whendee Silver [wsilver@berkeley.edu]• Dennis Baldocchi

[baldocchi@berkeley.edu]• Lindsey Hendricks

[lindsey.g.hendricks@berkeley.edu]

ESPM 111 Ecosystem Ecology

Class Web Site

• bcourses.berkeley.edu

ESPM 111 Ecosystem Ecology

Grading

• Homework assignments: 30%– five problem sets on data reduction and

interpretation. • Midterm: 35%• Final, last lecture period: 35%

ESPM 111 Ecosystem Ecology

Textbook/Readings• Principles of Terrestrial Ecosystem Ecology. F.

Stuart Chapin III, Pamela A. Matson, and Peter Vitousek. 2011. 2nd edition Springer-Verlag, New York, NY USA

• http://link.springer.com/book/10.1007/978-1-4419-9504-9

ESPM 111 Ecosystem Ecology

(this is what they really look like….)

Course OverviewKey Topics

• History• The Physical Environment

– Climate, Geology, Soils

• Biogeochemical Cycling– Carbon, Nitrogen, Phosphorus

• The Biophysical System– Water, Energy, Plants, Animals

• Ecosystem Dynamics– Recruitment, Mortality, Competition, Disturbance, Succession and Movement

• Ecosystem Scaling, Modeling and Global Ecology• Landscape Ecology• Global Change and Ecosystems• Ecosystem Management and Sustainability

ESPM 111 Ecosystem Ecology

Key Points

• Define an Ecosystem• Define Key Terms• Define Fluxes, Pools and Turnover time• Describe Ecosystems as Complex

Systems

ESPM 111 Ecosystem Ecology

Ecology

• The science of the relationships between organisms and their environments

• Name is derived from:– Oikos (Greek) and Ökologie (German): house, – Logie (German) and Logia (Greek): study– ‘Study of the House’

ESPM 111 Ecosystem Ecology

Other Fields of Ecology

• Organisms– Microbial Ecology– Plant Ecology– Animal/Wildlife Ecology

• Processes– Biophysical Ecology– Physiological Ecology– Molecular Ecology– Fire Ecology– EcoHydrology

• Systems– AgroEcology– Aquatic Ecology– Behavioral Ecology– Community Ecology– Forest Ecology– Landscape Ecology– PaleoEcology– Population Ecology– Tropical Ecology– Urban Ecology– Wetland Ecology

ESPM 111 Ecosystem Ecology

Related Fields

• Biogeography• Biogeochemistry• Ecological

Climatology• EcoHydrology• Biometeorology

ESPM 111 Ecosystem Ecology

ESPM 111 Ecosystem Ecology

Ecosystem Ecology

• ‘Study of interactions among organisms and their physical environment as an integrated system’– Chapin et al

This is not ‘Tree-Hugging 101’

ESPM 111 Ecosystem Ecology

What is an ecosystem?

• Bounded ecological system consisting of all the organisms in an area and the physical environment with which they interact– Biotic and abiotic processes– Pools and fluxes

• Levels (Hierarchy) of Organization– Organisms– Populations– Communities– Biomes

Other Ecological Terms and Concepts

• Niche– set of biotic and abiotic conditions in which a

species is able to persist and maintain stable population sizes

• Trait– Properties of individuals that enhance their

performance in a niche– They occur through evolution to enhance

survival and reproductive successESPM 111 Ecosystem Ecology

ESPM 111 Ecosystem Ecology

“all biologists know, biological systems don’t obey the laws of physics.”

..a referee of a paper by George Oster, ESPM Professor

Nuzzo R (2006) Profile of George Oster. Proceedings of the National Academy of Sciences of the United States of America 103:1672-1674

How to Study and Understand Ecosystems?

Is it Biology? Is it Chemistry? Is it Physics?

ESPM 111 Ecosystem Ecology

Paradigm Shift from a Mechanical Clock like Mechanical/Newtonian work to one of Complexity

And understanding the limitations and new way of thinkingComplex systems forces us to deal differently in how we study, quantify, predict, manage and manipulate complex systems

ESPM 111 Ecosystem Ecology

Ecosystem Ecology, the Baldocchi-Biometeorology Perspective

• Physics wins– Ecosystems function by capturing solar energy

• Only so much Solar Energy can be capture per unit are of ground

– Plants convert solar energy into high energy carbon compounds for work• growth and maintenance respiration

– Plants transfer nutrients and water down concentration/potential energy gradients between air, soil and plant pools to sustain their structure and function

– Ecosystems must maintain a Mass Balance• Plants can’t Use More Water or Carbon than has been acquired

• Biology is how it’s done– Species differentiation (via evolution and competition) produces the structure and

function of plants, invertebrates and vertebrates– In turn, structure and function provides the mechanisms for competing for and

capturing light energy and transferring matter• Gases diffuse in and out of active ports on leaves, stomata

– Bacteria, fungi and other micro-organisms re-cycle material by exploiting differences in redox potential; they are adept at passing electrons and extracting energy

– Reproductive success passes genes for traits through the gene pool.

ESPM 111 Ecosystem Ecology

Biological Systems Do Follow a ‘New’ Set of Physical Laws,Associated with Complexity and Complex Systems,

Where the Whole Acts Differently than the Sum of the Parts

Basic Ecosystem

Energy:Sunlight

Atmosphere:CO2, Rain, Temperature

Soil:Reservoir for Water and Nutrients,Anchorage for Roots, Habitat for

Microbes, Invertebrates andVertebrates

Primary Producers:Autotrophs, Plants

Consumers:Herbivores and

Carnivores

Decomposers:Heterotrophs,

Bacteria, Archaea,Fungi, Invertebrates

CO2

H2O

Challenge to Ecosystem Ecology is to Define the Rates/Velocitiesassociated with the Arrows and the Size of the Pools

ESPM 111 Ecosystem Ecology

Ecosystem Ecology, v2, the Processes

Physiology:Photosynthesis,

Respiration, Transpiration

Weather:Light Energy, Temperature,

Rainfall, Humidity, WindVelocity, CO2, soil

moisture

Growth and Allocation:Leaves, Stems, Roots,

Light Interception, Water andNutrient Uptake

Biogeochemistry:Decomposition,

Mineralization, Nitrification,Denitrification

Ecosystem Dynamics:Reproduction, Disperal, Recruitment,Competition, Facilitation, Mortality,

Disturbance, Sucession

Soil:Texture, DEM, C/

N,bulk density,Hydraulic Properties

EcoPhysiology:Leaf area index, plant

functional type,photosynthetic capacity,canopy height, albedo

hours

days/seasons

years

hours/days

•Numerous and Coupled •Biophysical Processes, •Fast and Slow

•Numerous Feedbacks, •Positive and Negative

Ecological Stoichiometry, CO2-H2O-N-PC106H263O110N16P

• CO2– Primary source of high-energy sugars, CH2O

• Nitrogen– Key component in RUBISCO, the enzyme that fixes CO2, and

amino acids that form proteins

• Phosphorus– Key component of ATP and NADPH, the energy compounds

central to many metabolic processes

• H2O– Keeps cells turgid– Solvent for transferring nutrients through solution– Lost via stomata

ESPM 111 Ecosystem Ecology

ESPM 111 Ecosystem Ecology

‘bacteria are astonishingly good at finding energy that will let them make a living. More or less everywhere the earth brings together substances with different redoxpotentials, there’s a bacterium that knows how to take advantage of the situation by passing electrons from one to the other and skimming off energy as it does’.

Oliver Morton, 2008 Eating the Sun: How Plants Power the Planet

Microbes make the BioGeoChemical Cycles Revolve

Fluxes, Pools and Turnover Time

• Flux = Mass per unit Volume per unit Time• Flux Density= Mass per unit Area per unit

Time• Pool or Reservoir= Mass per unit Volume, C• Turnover Time= e-folding time for a change in

pool size,

ESPM 111 Ecosystem Ecology

CF

Conservation Budget

ESPM 111 Ecosystem Ecology

Change in Pool Size, C, Equals the Flux in, Fin, minus the Flux out, Fout, of the Pool

in outC F Ft

Units: moles m-3 y-1

Holds for Energy, Water, Carbon, Nitrogen, etc

Summary

• Ecosystem Ecology involves– The Study of a Complex, Living System comprised of

plants, microbes, invertebrates and vertebrates– Autotrophs (plants) capture solar energy and convert it

into Chemical Energy– Chemical energy is used to drive the metabolism of

heterotrophs, herbivores, and higher trophic levels– Ecosystems sustain themselves by cycling of material

between the atmosphere, biosphere and pedosphere– Complex Behavior occurs due to the multiple and non-

linear feedbacks between fast and slow processes and big and small pools

– ‘Physics Wins, Biology is how its Done’

ESPM 111 Ecosystem Ecology

Class Reinforcement

• What are Ecological Fluxes?– Give Examples

• What are critical ecological pools?– How may they change?

ESPM 111 Ecosystem Ecology