Environmental Studies Flashcards
Population ecology
The factors influencing the population size, growth rate, growth forms and distribution of individuals inside a population
Individual
A single organism that forms part of a species
Species
A group of organisms with similar characteristics. which produce fertile offspring
Population
A group of organisms of the same species that are found in a particular area and can crossbreed freely
Community
A group of populations occurring in a particular area
Ecosystem
A unit of plant and animal communities in interaction with each other as well as with the non-living factors in a particular area
Environment
The external factors, living and non-living, surrounding an organism and influencing its development and survival
Habitat
The specific environment in which a plant or animal species normally occurs
Population size
The total number of individuals in a population
Population density
The number of individuals of a population per unit area
Population Parameters
Natality
Mortality
Immigration
Emigration
Determining population size
- Direct technique > Census
- Indirect technique > Mark-recapture/Quadrant
Environmental resistnace
All limiting factors that prevent unlimited growth in a population
Examples of limiting factors
- Shortage of food and water
- Shortage of living space
- Shortage fo shelter
- Predation
- Disease and parasitism
- Accumulation of toxins
Population growth forms
- Geometric J-shaped
- Logistic S-shaped
Carrying capacity
The maximum number of individuals that a specific environment can sustain
Stable population
A population whos numbers fluctuate around the carrying capacity
Migration
When a population moves from its original habitat and returns later