Chapter - Ecology Flashcards
Ecology
The study of the interrelationships between plants, animals and their environment
Ecosystem
Organisms and their interactions with the environment
Eg. Grassland, woodland, bog, seashore
Biosphere
The parts of the earth that support life
Habitat
The environment where an organism lives
Niche
The role of an organism in the ecosystem
Community
Different species sharing the resources in an ecosystem
Abiotic factors
Non living factors
Examples of climatic factors
Light intensity, wind, exposure, temperature, day length
Edaphic factors
Factors relating to soil
Eg. pH, water content, humus content, mineral content
Biotic factors
Influences of living organisms on each other
Examples of biotic factors
Competition, predation, Feeding, Disease, nitrogen-fixing bacteria, decomposers
Autotrophs
Organisms that make their own food -called producers
Photosynthetic
Use sunlight to make carbohydrates using chlorophyll
Change solar energy into chemical energy
Chemosynthetic Autotrophs
Bacteria which make food using chemical reactions other than photosynthesis
Heterotrophs
Cannot make their own food -called consumers
Herbivores
Primary consumers -only eat plants eg.rabbits
Carnivores
Secondary consumers -eat only animals eg.cats
Omnivores
Secondary consumers- eat both plants and animals eg.humans
Detritus feeders
Eat dead and decaying vegetation eg.dugesia
Decomposers
Break down dead organic matter usually by extracellular digestion eg.fungi
Example of energy flow/food chain in the rocky sea shore
Seaweed->Periwinkle->Dog Whelk->Gull
Food chain
Pathway along which energy is passed from one species to another
Why are food chains usually short?
Only 10% of energy assimilated by next trophic level -> short, usually less than 5 levels
Grazing food chains
Begin with plants
Detritus food chains
Begin with detritus
Trophic level
Feeding level or stage in a food chain
Food web
Two or more interconnected food chains
Pyramid of numbers
A diagram showing the numbers of organisms at each trophic level
Limitations of the Pyramid of Numbers
-doesn’t take into account the size of the organisms
Nutrient recycling
Elements that are used to produce nutrients ads in limited supple so they have to be recycled
Nitrogen fixation
Converting atmospheric nitrogen in soluble nitrogenous compounds eg.nitrates or ammonia
Nitride action
Conversion of ammonia to nitrites or converting nitrites to nitrates by nitrifying bacteria
Denitrification
Conversion of nitrates to atmospheric nitrogen by denitrifying bacteria
Pollution
Any harmful addition to the environment
Pollutant
Any substance that causes damage to the environment
Sulphur Dioxide as a pollutant
- Source: burning fossil fuels
- Damage: causes acid rain(a) kills fish
(b) kills trees
(c) damages buildings - Control: (a) reduce amount of fossil fuel burning
(b) remove SO2 from gasses by scrubbing
Burning Fossil Fuels effects
CO2: global warming
SO2: causes acid rain
Soot particles: respiratory tract problems
Conservation
The management of the environment to maintain existing populations
Forestry
Example of conservation practise-plant a tree for each cut down
Benefits of convservation
Biodiversity prevents outbreaks of disease,
Possible source of medicines
Waste management
Needed to prevent pollution
Waste disposal methods (x3)
Landfill
Incinerators
Recycling
