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Ecosystem Ecology, ESPM 111 Ecosystem Ecology, ESPM 111 • Whendee Silver [[email protected]] • Dennis Baldocchi [[email protected]] • Lindsey Hendricks [[email protected]] 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 Overview Key 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 • Systems – Microbial Ecology – AgroEcology – Plant Ecology – Aquatic Ecology – Animal/Wildlife Ecology – Behavioral Ecology • Processes – Community Ecology – Biophysical Ecology – Forest Ecology – Physiological Ecology – Landscape Ecology – Molecular Ecology – PaleoEcology – Fire Ecology – Population Ecology – EcoHydrology – Tropical Ecology – Urban Ecology – Wetland Ecology ESPM 111 Ecosystem Ecology Related Fields • Biogeography • Biogeochemistry • Ecological Climatology • EcoHydrology • Biometeorology 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 ESPM 111 Ecosystem Ecology 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 success ESPM 111 Ecosystem Ecology How to Study and Understand Ecosystems? Is it Biology? Is it Chemistry? Is it Physics? “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 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 thinking Complex 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 ESPM 111 Ecosystem Ecology Basic Ecosystem Atmosphere: CO2, Rain, Temperature Energy: Sunlight CO2 H2O Primary Producers: Autotrophs, Plants Decomposers: Heterotrophs, Bacteria, Archaea, Fungi, Invertebrates Consumers: Herbivores and Carnivores Soil: Reservoir for Water and Nutrients, Anchorage for Roots, Habitat for Microbes, Invertebrates and Vertebrates Challenge to Ecosystem Ecology is to Define the Rates/Velocities associated with the Arrows and the Size of the Pools Ecosystem Ecology, v2, the Processes Weather: Light Energy, Temperature, Rainfall, Humidity, Wind Velocity, CO2, soil moisture EcoPhysiology: Leaf area index, plant functional type, photosynthetic capacity, hours canopy height, albedo •Numerous and Coupled Physiology: •Biophysical Processes, Photosynthesis, Respiration, Transpiration •Fast and Slow hours/days •Numerous Feedbacks, Growth and Allocation: Leaves, Stems, Roots, •Positive and Negative Light Interception, Water and Nutrient Uptake Soil: Texture, DEM, C/ days/seasons N,bulk density, Hydraulic Properties Biogeochemistry: Decomposition, Mineralization, Nitrification, Denitrification years Ecosystem Dynamics: Reproduction, Disperal, Recruitment, Competition, Facilitation, Mortality, Disturbance, Sucession ESPM 111 Ecosystem Ecology Ecological Stoichiometry, CO2-H2O-N-P C106H263O110N16P •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 Microbes make the BioGeoChemical Cycles Revolve ‘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 redox potentials, 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 ESPM 111 Ecosystem Ecology 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, C F ESPM 111 Ecosystem Ecology Conservation Budget Change in Pool Size, C, Equals the Flux in, Fin, minus the Flux out, Fout, of the Pool C F F t in out Units: moles m-3 y-1 Holds for Energy, Water, Carbon, Nitrogen, etc ESPM 111 Ecosystem Ecology 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.
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