Class Notes (838,049)
Canada (510,626)
Biology (6,824)
Biology 1001A (1,727)
Tom Haffie (1,170)

Biology 1001A - Lecture 24.docx

5 Pages
Unlock Document

Biology 1001A
Tom Haffie

Biology 1000A Lecture 24: Ecosystem Ecology Outline:  Energy Flows, Nutrient Cycle  Pyramids of Energy, biomass, numbers  Nutrient Cycles and Reserves: Water, Carbon  Always more energy available at lower Trophic levels o Larger population sizes at lower levels o Biomass is also larger at lower levels A few terms…  Community: All of the organisms living in some defined space  Ecosystem: A biotic community and it’s abiotic environment functioning as a system  Ecosystems are OPEN, not CLOSED systems o Energy inputs and outputs  Heat, chemical, sound energy outputs o Nutrient inputs and outputs  I.e. Lake  Streams coming into the lake is a source of input nutrients  Down flow stream is a way for nutrients to leave a system 2 Major Activities in Ecosystems: Production & Consumption  Production: New biomass is being created from inorganic substances  Consumption: Current biomass is being converted into new forms of biomass  (Diagram) 4 Major functional components:  Producers (Autotrophs)  Consumers (Heterotrophs) o Includes Decomposers  Energy  Nutrients Where does the energy come from?  99% of it comes from light energy (i.e. photosynthesis), harvest by photoautotroph  Chemical energy, harvested by chemoautotroph o Rely on chemical energy, area’s where sun doesn’t shine  Beneath Ocean (microbes) Nutrients  Chemical elements or compounds needed for growth or reproduction o Organic or inorganic  Organic contains carbon o Micronutrients & Macronutrients  Micronutrients: Something an organism needs in TRACE amounts  Macronutrients: Something an organism needs A LOT of (i.e. O 2  Nutrient Sources: o Geological Sources (mineral Soil) o Atmospheric Sources  i.e. Oxygen and Nitrogen o Oceans o Decomposition and Nutrient Cycling  If biomass did not break down, we would eventually run out of nutrients Energy flows up the food web…  Energy flows from source through the primary producers, through consumers and decomposers o Ecological Inefficiency: Some energy lost at each transfer between levels o Energy constantly being replaced from outside the ecosystem  Usually from the Sun Ecological Efficiency < 100%  Harvesting Efficiency: Portions of available food is consumed o Assimilation Efficiency: Proportion of energy CONSUMED is assimilated (digested) o Production Efficiency: Proportion of energy assimilated that becomes new tissue CLICKER Question:
More Less

Related notes for Biology 1001A

Log In


Join OneClass

Access over 10 million pages of study
documents for 1.3 million courses.

Sign up

Join to view


By registering, I agree to the Terms and Privacy Policies
Already have an account?
Just a few more details

So we can recommend you notes for your school.

Reset Password

Please enter below the email address you registered with and we will send you a link to reset your password.

Add your courses

Get notes from the top students in your class.