Topic 2: Biomes & Ecosystems

Question 1

BIOMES

• A biome is a geographical area with similar climates and organisms.
• Dividing the world into a few ecological zones is difficult due to the small scale variation that exists everywhere on earth.
• The boundaries are drawn based on their average conditions.
• There are a number of schemes which developed previously;
• Life zones- classification based on temperature and rainfall
• Biome types- classification based an apparent characteristics , outward features or appearance of ecological species

Answer 1

LAND BIOMES

• Rainforests, deserts, grasslands, deciduous forest, boreal forrest, tundra, inland aquatic & managed aquatic
• An area’s biome is determined mostly by its climate

Question 2

BIOMES AND ECOSYSTEMS

• Biomes are not ecosystems.
• Biomes contain many ecosystems.
• Biomes are large areas of similar climatic conditions where as ecosystems are smaller specific areas within Biomes that contain interactions between biotic and abiotic factors.
• Ecosystem refers to all the communities that inhabit a particular area within a biome and the non-living environment around them.

Answer 2

EFFECT OF ABIOTIC FACTORS ON COMMUNITIES

• The composition of a community is a direct result of the environmental conditions of the habitat.
• Species evolve to exist within a particular environment.
• Eg. Different regions which have similar environmental conditions usually show species wth similar characteristics.

Question 3

TYPES OF ABIOTIC FACTORS

• Sunlight: The energy source for producers
• Too much sunlight results in adaptations to reduce water loss
• High competition for sunlight (rainforests) results in fast growing, large leafed plants
• Water:
• Low levels of water in deserts results in producers with adaptations to reduce water loss (small, water storing)
• Animals in arid conditions are adapted for the same reason (big ears to cool blood)
• Low water and high sun; harsh conditions so sparse population
• High water and medium sun; good conditions so dense population

Answer 3

TYPES OF ENVIRONMENTAL FACTORS

• Temperature: Enzymes action for all species requires specific temperatures, therefore species found in deserts will be different to species found in mountain ranges
• Wind: Strong winds will drive the adaptations of smaller plants
• Salinity: Coastal plants show adaptations to excrete salt from their roots

Question 4

LEVELS OF LOCATION

• Where an organism is located can be studied from a vast range of levels.
• These levels range from broad to specific

Answer 4

BIOSPHERE

• Broadest category
• Refers to the part of the earth in which living organisms are found, eg. terrestrial or marine
• Can be divided again into biogeographical areas which is the geographic distribution of an organism, eg. Australia, Pacific Ocean

Question 5

BIOMES

• Refers to an area with similar climatic conditions
• eg. desert, grassland, tropical
• Organisms living in these areas usually show similarities to others that live in the same biome in different parts of the world

Answer 5

HABITAT

• Within each biome we find different habitats
• These are even more specific
• eg. a stream in a tropical biome, a eucalyptus forest

Question 6

MIRCOHABITAT

• Areas within each habitat differ from the rest of the habitat
• These are the most specific
• eg. under the rocks in a tropical forrest stream

Answer 6

DESCRIBING ANIMAL LOCATIONS

• Biosphere
• Biogeographical
• Biome
• Habitat
• Microhabitat