Topic 2: The Ecosystem Flashcards
Define species
A group of organisms that interbreed and produce fertile offspring
Define population
All of the organisms of the same species living in the same area at the same time
What would you call a group of populations living in and interacting with one anther in a common habitat?
Community
What is a niche?
An organisms’ share of a habitat and it’s resources as well as the role it plays in the ecosystem
Define habitat
The place where a particular organism lives
What is a biome?
A collection of ecosystems sharing similar climatic conditions e.g. Tundra
What would you call the part of the planet inhabited by living organisms?
Biosphere
What are biotic factors? Give three examples
Living factors
E.g. Predators, diseases, food availability
What are abiotic factors? Give three examples
Non-living organisms
E.g. Climate (lack of rain), pollution, pH
What are density dependent factors? Give three examples
Factors that are affected by density of population - tend to be biotic
E.g. Good availability, disease, predators
What are density independent factors? Give two examples
Factor that aren’t affected by density of population - tend to be abiotic
E.g. Flooding, forest fires
Define carrying capacity
The number of organisms that an area or ecosystem can support sustainably over a long period of time
What things could effect the climate?
Precipitation, insulation, temperature
How does the climate effect the NPP
The climate effects photosynthesis which effects the producers (who photosynthesis)
How do you work out the NPP?
Rate of photosynthesis minus the rate of respiration
NPP is more or less the energy produced to pass on to the primary producer
What effects species diversity?
NPP
Describe the effect of light intensity on photosynthesis in terms of a graph
Rate of photosynthesis increases until it reaches a certain point and then continues at a steady rate - neither increasing not decreasing
Give four examples of biomes.
- Tropical rainforest
- Temperate forest
- Tundra
- Desert
Describe the effect of temperature on photosynthesis in terms of a graph
The rage increases at an exponential rate until the temperature reaches 25 degrees Celsius - after this temperature the rate decreases
Describe the effect of carbon dioxide concentration on photosynthesis in terms of a graph
The rate increases at an exponential rate and then levels out to a steady rate - neither increasing or decreasing
What are the two types of autotrophs and what is the difference between them?
Chemo autotrophs - use chemicals as an energy source
Photo autotrophs - use light as an energy source (photosynthesize)
What are the inputs and outputs of photosynthesis?
Inputs - carbon dioxide, sunlight and water
Outputs - glucose and oxygen
What is the transformation of energies in photosynthesis?
Light energy to chemical energy
Sunlight to glucose
What is photolysis?
Using light to split atoms
What is the process of photosynthesis?
Chlorophyll traps sunlight energy and uses it to split water molecules and attach the hydrogen to the carbon dioxide to produce glucose
Bacteria, algae, fungi, plants and animals - are that biotic or abiotic features of an ecosystem?
Biotic
Water, temperature, light, minerals an salinity - biotic or abiotic features of an ecosystem?
Abiotic
How does energy enter an ecosystem?
Through solar energy which producers convert
If the first tropic level are autotrophic, what are the other tropic levels?
Heterotrophic
If the primary consumer only eats the producers, that would make it a…
Herbivore
What are the seven characteristics of living organisms?
MRS GREN
Movement Reproduction Senses Growth Respiration Excretion Nutrition
What are the five kingdoms?
Plants are better producers fullstop
Plants Animals Bacteria Protozoa Fungi
What is the order of the hierarchy? Starting with Kingdom…
Kings play chess on golden sands
Species Genus Family Order Class Phylum Kingdom
Why is international classification used?
So that foreign scientists can work together
What is parisitism?
One species (parasite) benefits at the expense of another (host)
What is a symbiotic relationship?
Organisms that live together and both benefit e.g. rhino and blackbird
What is a mutualistic relationship?
The sessile organism (plant) relies on another, moving organism (bee) to survive
What is an intraspecies relationship?
Competition of the same species such as red and grey squirrels
What do pyramids of number show?
The size of the boxes represent the number of organisms
What is an advantage of pyramids of numbers?
Easy to construct
What are the two disadvantages of pyramids of number?
If individual primary producers occur, large inverted pyramids occur
Don’t show the ecological relationship between tropic levels
What do pyramids of biomass show and what is a disadvantage?
They represent the dry mass of organisms
Dis - only represent a ‘momentary standing stock’
What are three advantages of pyramids of productivity/energy?
Always show pyramid shape, represent true ecological relationships between trophic levels, underline 1st and 2nd laws of thermodynamics
What are the disadvantages of pyramids of productivity?
No indication of ecosystem or energy into system, no units of time
What are the inputs and outputs of a population?
Inputs - births and immigration
Outputs - deaths and emigration
What is the equation for population?
Population = (births+immigration)-(deaths+emigration)
In a S-shaped curve and a J-shaped curve, what is the first phase called?
Lag phase
In a S-shaped curve (sigmoidal) what is the second and final phases called?
Log phase and stable phase
What are the six features of r organisms?
- Ability to increase population rapidly
- Lots of offspring
- High offspring mortality
- Short lifespan
- Poor competitors
- Found in variable and unpredictable environments
Give some examples of r and K organisms
r - rats, salmon, bacteria
R - pandas, humans, horses
What’s the different between transfer and transformation?
Transfer - the movement of material or energy from one place to another without changing the material
Transformation - changes the form of the material or energy as it moves from one storage to another
What three things can happen to the light/solar energy as it enters the earths atmosphere?
Can be absorbed, reflected or transmitted
Looking at photosynthesis as a system, why are the inputs and outputs?
Inputs- sola energy, radiation energy, water, carbon dioxide and sunlight
Outputs - chemical energy (glucose), oxygen
If condition are good for photosynthesis what can we assume about the NPP? What does this mean?
High NPP which means a stable ecosystem that supports high species diversity
Looking at respiration as a system, what are the inputs and outputs?
Inputs - chemical energy, oxygen, carbohydrates
Outputs - ATP energy, carbon dioxide and water
What is psammoseres?
Ecological succession that began life on newly exposed coastal sand. Most common psammoseres are sand dune systems.
What would the condtions be like at the beginning of a psammoseres at sand dunes compared to at the end in an oak forest?
Sand dunes - unstable, extreme conditions, low biodiversity, low biomass
Oak forest - stable, high biodiversity, high biomass
How would you measure the biomass of ONE trophic level and why is it best to measure the biomass of the producers?
Use the dry biomass - dried matter can be measured in a bomb calorimeter to find the no. of calories
Measuring biomass of poducers can indicate information about the other trophic levels.
Although counting is accurate, why is it not always the best method to measure biotic factors of a system?
time consuming, sometimes dangerous, organisms need to be large, slow moving or sessile
What are two types of sampling?
Systematic and Random
When would you use systematic sampling instead of random sampling?
When there is an environmental gradient e.g. dry to wet, acid to alkali, shade to light
When would you use random sampling as a pose to systematic sampling?
When comparing two or more areas e.g. city and country
When using tools to monitor physical factors, if the tools are numerical what must be done to them?
Calibrated
Indirect sampling mathods are used when and include…
When you can’t measure a species directly e.g. whale
Methods: radar, sonar, cameras, satelitle imagery
What is the purpose of the lincoln index?
Looks at the estimation of populations, e.g. capture, mark, recapture
What does the Simpsons index do? And what is the formula?
Looks at species diversity and changes over time.
Species diversity = N(N-1) divided by sum of n(n-1)
If there a lot of mayfly nymphs, what does this indicate?
The water is fairly clean
What is more accurate than a thermometer to measure temperature?
Digital thermometer
Universal Indicator can be used to indicate the pH, what is a limit of this and what could be used instead?
Doesn’t work if colour blind - could use a digitl pH meter.
What is an EIA? When it used?
In the UK, an environmental Impact Assessment must be submitted before planning permission is considered when there is ANY major development e.g. factories, wind farm, road building.
What are the 4 stages to an EIA?
1) Baseline measurements to establish a before pic
2) Assessment of possible environmental impacts
3) Monitor changes during and after development
4) Publish reports
Whaa is the formula to estimate the average density when using quadrats to estimate a population?
total no. of individuals counted divided by (number of quadrats x area of each quadrat)
As an ecosysystem develops in succession, the NPP will initially increase but is the only factor which then decreases in the later seres, why?
NPP= GPP - Respiration
There are more animals in later seres which means more respiration and therefore a lower NPP.
