Topic 10 - Ecosystems Flashcards
ecosystems (noun)
interaction btwn living organisms and the environment
abiotic means
non-living parts
- Non living chemical and physical part sof the environment
biotic means
living parts
Community
all organsims living in a particular community
Biodiversity
Variety of different species in an area
what is a producer?
any photosynthetic (creates its own food by photosynthesis) organism
What is trophic level?
position organism holds in a food chain/web, pyramids of energy or biomass
what is dry mass and why good
- it’s the acc mass of the organism bc there is no water included
what is biomass?
the dry mass of all the living organisms in an area
how can ecosystem structure be represented?
- via a pyramid of number, biomass, or enegy
pyramids of numbers?
easy/hard/accurate to measure? and the bad side?
- easiest to measure but can be distorted by large organisms
1 oak tree can feed a hundred worms
pyramids of biomass?
easy/hard/accurate to measure? and the bad side?
- more accurate, but dry mass has to be used and they don’t account for rate of production of biomass
pyramids of energy?
easy/hard/accurate to measure? and the bad side?
- most accurate, but more difficultto measure and use an outdated definition of enegy
Ecosystems vary in size.
4 Varied sizes of ecosystems?
- biosphere
- biome
- habitat
- microhabitat
biosphere
- all life supporting environments on the earths surface
biome
- major ecosystems, e.g tundra, desert
tundra = cold dessert, layer of is=ce below the soil
habitat
natural home/environment for organisms to live
microhabitat
- localised/ small scale environment that supports a distinct flora and fauna (e.g pond, apple)
Niche?
Organisms role/place in an eco-system.
Population?
Number of organisms of a specific species.
Distribution?
Spread of an organism in a habitat/environment.
How do eco-systems change?
Why might they change?
-Deforestation -> Losing habitat/food source
-Hunting -> Killing them out. Loss of animal + Potential food for others.
-Introducing new species
-Migration -> New Predator
-Natural Fires/Natural DIsasters
-New Diseases (Plants/animals/food sources)
Troph (Latin meaning) ?
Feeding
Hetro (Latin meaning)
Other
Auto (Latin meaning)
Self
Vores (Latin meaning)
Carnivore/Herbivore
Eating/Feeder
Detriti (Latin meaning)
Waste
3 Groups of Biotic Factors
Produces/Autotrophs
Consumers/Heterotrophs
Decomposes/Detritivores
Order of the food chain
Primary Consumer (Herbivore) -> Secondary Consumer (Carnivore) -> Tertiary Consumer -> Decomposer (Micro-organisms that break down organism’s remains E.g. Fungi and bacteria)
Food chain?
Sequence of feeding interactions between organisms in a given habitat.
What is productivity?
Refers to the rate of generation of biomass in an eco-system.
What is a decomposer?
bacteriaor fungi that break down dead animal/palnt material
What is a consumer?
a living creature that eats organisms from a different population
2 types of productivity?
- gross primary productivity
- net primary productivity
what is GPP
(Gross Primary Productivity)
- amt of organic matter synthesised by producers per unit area in unit time
- refers to total productivity including energy utilised for respiration by the producers
- depends on chlorophyll content
GPP - rate of increased body mass or rate of organic matter synthesised by producers + rate of respiration and other damages
(How much biomass that grass is making for that area, over a specific time.)
What is NPP
(Net Primary Productivity)
- amt of organic matter stored by producers per unit area in unit time
- refers to net productivity that is converted to organic matter excluding the energy utilised for respiration (R) by the producers
- Depends of chlorophyll content
NPP = rate of organic matter syntheised by photosythesis by producers - the rate of energy utilised for respiration (R) and other damages
What is organic matter
Refers to the large source of carbon-based compounds found within natural and engineered, terrestrial, and aquatic environments. It is matter composed of organic compounds that have come from the feces and remains of organisms such as plants and animals
What is productivity?
rate of generation of biomass in an ecosystem
(is measured as biomass in a given area in a given time)
- its the percentage of energy entering the ecosystem incorporated into biomass in a particular trophic level
what is the equation for Net Primary Productivity
NPP= GPP - R
Equation for Gross Primary Productivity
NPP + R = GPP
random
Stochasticity
element of unpredictability variability in anything
(lack of consistency or fixed pattern; liability to vary or change)
Equation for enegy effiency
(energy transferred to next level / total energy in) x100
effiency = (biomass transferred to the next trophic level/Biomass available at the next trophic level ) x100
How do ecosystems evolve?
thtough ecological succession
what is ecological succession?
process by which the structure of a biological community evolves over time
what are the 2 types of ecological succession?
- primary succession
- secondary succession
what is primary succession?
- occurs in lifeless areas
- regions where soil i sincapabl eof sustaining life (e.i bc of lava flow, or rocks left by retreating glaciers)
what is Secondary succession?
- process started by an event (e.g a forest fire, harvesting, hurricane) that reduces an already established ecosystem (e.g a forest, a wheat field) to a smaller population of species, as such, secondary succession occurs on a pre-existing soil.
Climax community model?
Intermediate Disturbance Hypothesis
