Chapter 3: Ecosystems Flashcards
Open System
Receives inputs AND produces outputs of BOTH energy and matter
Closed System
Receives inputs and produces outputs of energy but NOT matter
Biomagnification
the concentration of toxins in an organism as a result of ingesting other plants or animals(animals higher up in the food chain will have higher concentrations of toxins)
Bioaccumulation
the accumulation of a toxic chemical in the tissue of a particular organism
combine easily with fats and build up over time
(DIFFERENT FROM BIOMAGNIFICATION, has nothing to do with consuming other species)
Hypoxia
Lack of dissolved oxygen (affects the st lawrence belugas)
Eutrophication
Nutrient over-enrichment in a body of water(can result from both natural and man-made influences)
Feedback Loop
When a systems output also serves as input to that system (input-output loop)
What is the difference between a NEGATIVE feedback loop and a POSITIVE feedback loop?
a NEGATIVE feedback loop moves a system towards another direction to stabilize the system (eg. when the body is hot, it sweats to keep cool)
a POSITIVE feedback loop drives a system towards a further extreme(does not stabilize).
Dynamic Equilibrium
When system processes move in opposing directions at equivalent rates, eventually achieving equilibrium(NOT STATIC)
Homeostasis
The tendency of a system to maintain constant/stable internal conditions
Resistance
the strength of a systems tendency to remain constant
Resilience
How quickly a system will return to its original state after being disturbed
Emergent properties
Characteristics of a system that are not easily apparent by looking at its individual components alone
Autotrophs
Organisms that produce their own food energy(green plants, algae)
Gross Primary Production
conversion of solar energy to the energy of chemical bonds in sugar by autotrophs. Autotrophs use a portion
of this production to power their own metabolism by respiration(intake of oxygen/release of CO2)
Net primary production
The energy remaining after respiration by autotrophs(NPP=GPP-respiration)
Biomass
Total mass of organic material of which living organisms are formed
Secondary Production
The biomass generated by heterotrophs due to the consumption of autotrophs
Nutrients
Elements & compounds needed for survival
MACRONutrients
required in relatively LARGE amounts(eg. nitrogen, phosphorus, carbon)
MICRONutrients
required in SMALL amounts (eg. zinc)
High net primary productivity
ecosystems whose plants rapidly convert solar energy to biomass
Ecotones
transitional zones between 2 systems in which elements of different ecosystems mix
Rate from largest to smallest: biome, landscape, ecosystem
Landscape, Ecosystem, Biome
Define Remote Sensing & GIS
Remote sensing: satellites, technologies that collect info about an object from a distance
GIS: Geographic information system, computer software used in landscape ecology research
Nutrient cycles
the movement of nutrients through ecosystems
Pools(reservoirs)
Where nutrients reside for varying amounts of time(residence time)
Flux
The movement of nutrients among pools
What is the difference between a POOL and a SINK?
a pool releases more nutrients than they accept, while a sink accepts more nutrients than they release
Turnover time
the amount of time it would take for all the atoms/particles of a material to be flushed through a reservoir
Aquifer
Underground reservoirs of rock and soil that hold groundwater
Transpiration
Release of water vapor by plants
Water table
The upper limit of groundwater in an aquifer
About how much fresh water is easily accessible?
1%
What are potential sources that can contaminate groundwater?
Landfills, dumps, septic tanks
What is the largest reservoir of carbon? The second largest?
1st, Sedimentary rock.
2nd, The ocean
How do humans affect the carbon cycle?
- burning fossil fuels moves carbon from the ground into the air
- cutting forests and burning fields moves carbon from organisms into the air; moves carbon into the ocean causing ocean acidification
How is nitrogen fixation accomplished?
- by the intense energy of lightning strikes
- by the action of specialized nitrogen-fixing bacteria
nitrification
when ammonium ions are first converted into nitrite ions and then nitrate ions, by other specialized bacteria
How do animals obtain nitrogen?
By eating plants or other animals
Denitrification
converts nitrates from soil or water back into nitrogen gas(completes the carbon cycle)
How much of the earth’s atmosphere is made up of Nitrogen
78%
What is the Haber Bosch Process?
the synthetic production of fertilizers by combining nitrogen and hydrogen to synthesize ammonia
How does the Haber Bosch Process affect earth?
- enabled people to overcome limits on agricultural productivity
- increased emissions of nitrogen-containing greenhouse gases
- acidified water and soils
- reduced biodiversity of plants
How is the phosphorus cycle different from the carbon and nitrogen cycles?
Has no atmospheric component
Eutrophication
The process of nutrient-over enrichment, blooms of algae, increased production of organic matter, and ecosystem degradation
