Chapter 12 Flashcards
(36 cards)
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.
Tropical and subtropical dry broadleaf forests
Characterized by moderate temperatures but long dry seasons.
Dominated by deciduous trees, many that lose their leaves during the dry season.
Loss of leaves in the canopy allows the under canopy and shrub layers to receive more light.
Have less diversity than rainforests.
Have higher mammalian biomass than rainforests.
Tropical and subtropical Coniferous Forests
Characterized by low rainfall and moderate variability in temperature.
Populated by diverse groups of conifers whose needles are adapted to low rainfall and variable temperatures.
Thick canopy often leaves only ferns and fungi capable of making a living on the ground.
Temperate broadleaf and mixed forests
Characterized by variable temperatures and variable rainfall.
Includes conifers in the canopy layer.
Temperate Coniferous Forest
Characterized by warm summers and cool winters and enough rainfall to sustain a forest.
Dominated by Evergreen conifers.
Have highest levels of biomass of any terrestrial biome.
Include temperate rainforests.
Boreal forests/ Taiga
Characterized by low rainfall and cold temperatures.
Located in Northern latitudes.
Dominated by conifers.
World’s largest land of biome.
Still has relatively undisturbed large animal migrations.
Under threat due to climate change
Tropical and subtropical grasslands, savannas, and shrublands
Characterized by low rainfall (not enough to sustain a forest) and moderate to warm temperatures.
Dominated by grasses with some trees.
Home to large mammals.
Soon to only exist in natural parks.
Flooded grasslands and savannas
AKA Swamps.
Located tropically or sub-tropically and flooded seasonally or year round.
High avian diversity with both resident and migratory birds.
Montane grasslands and shrublands
Located at high altitude (alpine or subalpine) and above or below the treeline.
Plants adapted to cool temperatures and high light.
Tundra
Treeless cold climate Includes: -Artic: polar desert -Antarctic: Polar desert -Alpine: Above the treeline
Dwarf vegetation and lichens.
