1.7a Ecological Relationships and energy flow Flashcards
Ecology
The study of relationshis between organisms and their environment
Population
Number of organisms of a SINGLE species in a given area
Community
All the populations of plants and animal species in a particular area
Biodiveristy
The range of different species living in an area
Environment
The surrounding in which an organism lives
Ecosystem
The community (all the organisms and how they interact) and abiotic factors that affect them
Food Chain
Shows the feeding relationship and energy transfers between organisms
Trophic Level
The feeding level in a food chain - Level 1 always is a plant
Sun
Source of energy for all food chains
Biotic Factors
Living factors that affect where an organisms lives eg grazers, disease, predators
Abiotic Factors
Non living factors eg light , soil pH, temperature that affect where an organism lives
Quadrat
Square piece of equipment used in sampling (0.5m x 0.5m)
How to find the population of species by sampling an area
Set 2 tape measures at right angles
Select co-ordinates at random (to remove biased results)
Place quadrat
Count number of organisms or % cover
Record results
Repeat at least 10 times
Calculate average per quadrat
Calculate number per area sampled
How to find the effect of an abiotic factor by sampling in a changing environment
Place tape measure along the section being sampled e.g. from woodland to middle of field
At regular intervals along tape measure set quadrat down
Count/record % species present
Record results
Record abiotic factor at each stage e.g. temperature
Equipment to measure temperature
Thermometer
Equipment to measure soil pH
pH meter or soil pH testing kit
Equipment to measure light intensity
Light meter
Equipment to measure wind speed
Anemometer
Equipment to measure soil moisture content
moisture meter OR collect soil, weigh, dry until constant mass, record difference in mass - % moisture = difference in mass/original mass x 100%
Competition in plants
Compete for water, space, light, minerals in soil
Competition in animals
Compete for food, water, territory, mates
Food web
Interlinking food webs
Pyramid of numbers
Show number of organisms at each trophic level
Advantage - easy to count and no organisms killed
Disadvantage - does not take into account size of organisms
Pyramid of biomass
Show mass of living tissue (biomass) at each trophic level
Advantage - more accurate than pyramid of numbers as takes into account size
Disadvantage - difficult to collect data as will involve killing organisms
