B4b

Question 1

What affects the distribution of organisms and why?

Answer 1

• abiotic factors
• non-living, physical facters in an environmement
• e.g.light, temperature, water, oxygen, salinity and soil quality
• organisms are adapted to live in certain physical conditions, they are more likely to survive and reproduce in areas with these conditions
• many organisms can only survive in the conditions they’re adapted to

Question 2

What is zonation?

Answer 2

-the gradual change in the distribution of species across a habitat

Question 3

How do changes in abiotic factors lead to zonation?

Answer 3

• a gradual change in abiotic factors can lead to zonation
• e.g. in a coastal habitat, changes in salinity and soil depth cause zonation of plants
• few plants in the zone 1, marram grass can as it is adapted to live in salty conditions (nearest to the coast)
• lichens and mosses can grow in zone 2, out competing marram grass in less saline conditions
• shrubs such as heather and gorse can grow as they out compete lichens and mosses in the lower salinity and deeper soil of zone 3
• trees such as birch and oak out compete the shrubs in the very low salinity and deep soil in zone 4 (further inland)

Question 4

What is biodiversity?

Answer 4

-a measure of variety of life in an area?

Question 5

What does biodiversity include?

Answer 5

• amount of variation between individuals of the same species
• number of different species
• number of different habitats in an area

Question 6

What is the biodiversity like in forestry plantation?

Answer 6

• one specie of tree, planted for timbre
• blocks of trees planted at the same time, so many are the same age
• fewer plant species because trees are densely packed, leaving less room and sunlight for other plants
• fewer habitats as there isn’t enough plant species to create them, when the trees are felled habitats are also disturbed or destroyed
• fewer animal species because of the lack of habitats or sources of food

Question 7

What is biodiversity like in native woodlands?

Answer 7

• variety of tree species
• trees of different sizes and ages#
• variety of plant species
• variety of habitats
• variety of animal species

Question 8

What is biodiversity like in lakes?

Answer 8

• many different fish species
• variety of plant species
• variety of animal species

Question 9

What is biodiversity like in fish farms?

Answer 9

• one fish is farmed for food
• fewer plant species, as fish food is added and the food waste can cause algal blooms
• fewer animal species. Predators are kept out and pests (e.g.fish lice) are kept out. Also less food and lack of habitats because of the lack of plants

Question 10

Why is biodiversity important?

Answer 10

-more diverse ecosystems are better able to cope with changes in the environment