Ecology B16-18

• An ecosystem is a community of organisms and their environment.
• in a community each species depends on each other for food, shelter and protection
• Stable community - when all species and enviromental factors are in balance
• Unstable community - when there is an imbalance between the number of individuals or environmental conditions
• Abiotic factor - non living part of the environment that affects life eg temperature, light intensity, water availability
• Biotic factor - living parts of the environment that affect life eg predators, prey, competitors
• Quadrat: each of a number of small areas of habitat, typically of one square metre, selected at random to act as samples for assessing the local distribution of plants or animals.
• Transect - A line of points or transects that are placed at regular intervals along a line