Ecology Flashcards
What is an ecosystem?
All communities,organisms, factors (abiotic and biotic) in a particular area.
Factors can be interacting or interdependent
Self contained system - self supporting energy flow
Eg. Coral reef- marine ecosystem
What is habitat?
Geographical area occupied by ecosystem.
Subdivided -layers/zones
Micro habitats- forest canopy= leaves/ branches
What is the environment ?
All factors in a habitat that affect an organism.
Biotic factors- living
Abiotic - non living
What is population?
All members of 1 species in a habitat at one time eg. Number of people living in belfast
Calculation- BR/ Imigration- DR/emigr = pop. growth
What is community?
All organisms in one habitat at at one time (plants and animals- biotic factors)
What is species?
Group of potentially interbreeding animals which do not normally interbreed with other groups/ species to produce viable fertile offspring
What is classification and it’s use?
Arrange organisms into specific groups depending on characteristics.
Identify new species or unfamiliar ones.
Uses: identification, study how species change, compare biodiversity, and for conservation
What’s a key stone species?
Species in a community with a vital role- without them the ecosystem can collapse
What is niche?
Role of species in an ecosystem
Location, spacial habitat, function, relationships with organisms and environment
“ competitive exclusion rule” don’t want to compete
Eg. Red and grey squirrels
What are environmental factors that affect an ecosystem?
Abiotic ( non living) climate, physiography,soil
Biotic ( living) plants, animals, microbes
What abiotic factors affect an ecosystem ?
Fires, hurricane, tsunami, volcanos, global patterns of circulation ( rainfall, wind El Niño, ocean currents)
List the 2 abiotic components?
Inorganic- sulphur, boran - cycle through
Organic- proteins, lipids , carbohydrate - link biotic and abiotic
List the abiotic factors that affect an ecosystem?
Wind, rain, humidity, pH, light, temp
How can we measure biotic factors?
Greater no. Plants and animals - greater biodiversity
Distribution of animals depends on: food, mates, territories, adaption of an animal eg.camel to desert
What is the main biotic factor?
Competition
Habitats- limited resources- must compete with others for these- if unsuccessful and can’t move to another habitat they will DIE
“Survival of the fittest”
What do plants and animal compete for?
Plants- light, water, space, mineral salts
Animals- food, water, space, mates
What are the biotic components of an ecosystem?
Classified by mode of energy acquisition.
Producers- autotrophs- source of all food by photosynthesis
Consumers- heterotrophs- aerobic/anaerobic respiration
Decomposers- matter recycles- release organic components into soil- used by producers
What are tropic levels?
Rank in feeding order
- Producers
- Consumers
- Detritvores and decomposers
What’s the difference between matter and energy?
Neither can be created or destroyed.
Energy moves through a system in 1 direction ( FLOWS)
Matter cycles between living and non living things ( CYCLES)
What is in the first tropic level?
Autotrophs- plants- photosyn- glucose
Chemosynthetic bacteria- geothermal bacteria
What make up the 2nd 3rd and 4th tropic level?
Consumers.
Primary-consume producers- herbivores eg. Deer
Secondary- eat primary consumers- carnivores eg. Wolf
Tertiary - eat secondary consumers eg. Hawk
Omnivores- eat plant and animals
What is a food chain?
Relationship of how energy is transferred up the trophic levels.
Plants- herbivores- carnivores
What is a food web?
Network of interconnecting food chains.
More realistic
What happens if an organism is removed from a food web?
Has a major effect on other species
No rabbits, foxes eat more birds, more spiders, less grasshoppers
What is a pyramid of numbers, advantages and disadvantages?
Counts the number of species- not always a pyramid
Advantage- simple easy, good for comparison of Eco. Diff times of year
Disad.- no. species to great to measure, not include juvenilles, all organisms included regardless of size ( inverted pyramid)
What is pyramid of biomass, advantages and disadvantages?
Dry mass of living material per unit area- more accurate
Advant.- overcomes problems of pyramid of numbers
Disad.- diff to measure biomass exactly, time of year can affect biomass result, organisms of same size not always same energy content
What are pyramids of production?
Show flow of energy from producers through trophic levels.
Most of the time only 10% energy is transferred.
Not efficient
How is energy lost through the trophic levels?
Heat Waste Movement Respiration Top of level most dangerous as it has the least amount of energy
What happens to poisons and pesticides going up the food chain?
They become more concentrated- predator receives biggest dose
What limiting factors affect population size?
Food Water Space Shelter BR+immigration - DR+emigration = pop growth
What is ecology?
Study of organism and relationship with environment.
Includes biological, chemical and physical factors
