Class Notes (1,100,000)
CA (630,000)
UOttawa (30,000)
ENV (80)
Lecture

Class 5 - Global Environmental Change.docx


Department
Environmental Studies
Course Code
ENV 1101
Professor
Sonia Wesche

This preview shows page 1. to view the full 4 pages of the document.
Class 5
What is An Ecosystem?
A distinctive biotic community and the abiotic systems with which it interacts
The biotic grouping reproduces and perpetuates itself
Ex. Tundra, desert, temperate rainforest, coral reef
Concept: Systems
System: a network of relationships among components that interact with and influence one another through the
exchange of energy, matter and information
Open system: exchange energy and matter with systems outside itself
Closed system (earth): less common, earth contains all of its matter itself in a closed system
Positive feedback: reinforced a current system
Negative feedback: counteracts a change occurring
Trophic categories
Autotrophs (producers): organisms that create organic matter
o Most commonly plants via photosynthesis, but also includes chemosynthetic deep-sea bacteria
Heterotrophs (consumers): must consume organic material produced by other organisms
o Includes herbivores, carnivores, parasites, detritus feeders, decomposers
What is Capital?
Term originating in economics
Originally referred to $ in excess of that need to meet one’s own basic needs
Has been expanded to include human capital, social capital, cultural capital, religious capital
Ecosystem Capital
= Goods and services humans derive from the natural environment
There is historically no price or financial value assigned to the environment: it is treated as “free”
Ex. Grasslands fenced for pasture, water taken from rivers to drink, clean air for respiration
“Externalities”
You're Reading a Preview

Unlock to view full version