Ecology and the Environment Flashcards
Population
All the organisms of one species living in a particular habitat
Community
All organisms of a species found in a particular area at a certain time
Habitat
The palace where organisms live
Ecosystem
A community of living organisms together with their non-living environment
Quadrats help us to:
- Find the number of quadrats that contain the organism (frequency)
- Find the number of organisms per m2 (density)
- Estimate the number of each organism in the total area
Using Quadrats:
- Use quadrats to count the daises
- First make a pair of the axis that covers the area
- Then, using a random number generator, get a pair of numbers and use then for coordinates
- Place the bottom left corner of the quadrat on the coordinates, and count the daises in it
- Take 10 samples and find the average
Biodiversity
The amount of variation shown by species in an ecosystem is called the biodiversity of the ecosystem.
Biotic Factor (Living Factor)
A biological factor affecting an ecosystem
Biodiversity Measurement
- The number of species present (richness)
2. The relative abundance of each species (evenness).
Producers
Plants that photosynthesize. They supply the energy for the ecosystem
Consumers
Animals that eat the plants or other animals
Deomposers
Bacteria or fungi that digest decaying/dead material in order to recycle nutrients
A Physical Environment
This includes all the non-biological components (abiotic factors). The water, soil, temperature, etc.
A Physical Environment
This includes all the non-biological components (abiotic factors). The water, soil, temperature, etc.
Pyramids of Numbers
The organisms are plotted as separate blocks. The size of each block is related to the number of organisms. The producer always goes at the base, with each successive tropic level above it.
Pyramids of Biomass
Biomass is the total amount of living material in an organism. It is quite hard to measure, but it produces more useful results. The easiest way to do it is to multiply the number at each level by the dry mass (mass without water) of one of the organisms.
Pyramids of Energy Flow
Only about 10% of the energy entering a trophic level is passed on. Therefore energy is lost at each trophic level and it reduces the number of trophic levels.
Reasons for Energy Loss
- Materials not eaten by consumer
- Materials not digested by consumer, but is passed out as waste (feces)
- Energy used by the consumer for movement
- Energy used by the consumer in body metabolic process
- Energy used in generating heat
- Energy lost in the urine
Carbon Cycle
There is CO2 in the air and the trees absorb and release carbon through photosynthesis and respiration.
Animals also respire which releases CO2 back into the air.
From the trees and animals, decomposers release the carbon back into the air through respiration.
The trees and animals also go through fossilzation and turn into fossil fuels. The fossil fuels undergo combustion which releases carbon back into the atmosphere.
