Chapter 12 Flashcards
Ecosystem Ecology
The study of energy flow and the cycling of chemicals among the various biotic and abiotic components in an ecosystem.
Energy
The ability to do work.
Defined by the laws of thermodynamics.
First law of Thermodynamics
Energy can be changed from one form to another, but cannot be created nor destroyed. Total energy of a system remains constant.
Second law of Thermodynamics
In all energy conversions, the potential energy of the final state will always be less than the potential energy of the initial state.
You can’t break even.
There is always an increase in entropy (disorder) when energy is transferred.
Trophic Structure
The different feeding relationships within an ecosystem which determine the route of energy flow and the pattern of chemical cycling.
Trophic level of an organism is its position in a food web.
Producers
Reduce carbon to get food. They are autotrophs.
Consumers
They eat reduced carbon in the form of living organisms. They are heterotrophs.
Decomposers
They eat reduced carbon in the form of dead organisms. They are hetertrophs.
Food Web
Demonstrates feeding relationships in an ecosystem.
It includes a feeding hierarchy with trophic levels.
Energy is lost each time you go up a level due to the 2nd law of Thermodynamics.
Biomagnification
Top predators in a food web represent an accumulation of material from many lower animals.
If there are molecules in the environment that are not readily broker down or metabolized, they can reach high concentrations in top predators through biomagnification.
Nutrient Cycles
AKA Biogeochemical cycles.
Pathway by which an element moves through biology and the environment.
Lumpers vs Splitters
Lumpers: have a holistic view and define groups broadly.
Splitters: precise and create new categories to further subdivide groups.
Terrestrial Biomes
Tropical and Subtropical: -Moist broadleaf forests -Dry broadleaf forests -Coniferous forests Temperate broadleaf and mixed forests. Tropical and subtropical: -Grasslands -Savannas, and shrublands Temperate grasslands, savannas, and shrublands Flooded grasslands and savannas Montane grasslands and shrublands Tundra Mediterranean: -Forests (we live here) -Woodlands -Scrub Sclerophyll forests -Mangroves
Deserts and Xeric Shrublands
Xeric means of characterized by, or adapted to an extremely dry habitat.
Varies by temperature.
Created by man in some regions through the process of desertification.
Tropical and Subtropical moist broadleaf forests
Dominated by semi-evergreen and evergreen deciduous tree species.
High species diversity-half the world’s terrestrial species live here.