23.1 - Ecosystems

Question 1

Definition of ecosystem

Answer 1

Made up of all living organisms that interact with each other in an area, and the physical factors present.

Question 2

What two factors affect ecosystems?

Answer 2

• Biotic factors: living factors e.g populations and competition, habitat, food, partners
• Abiotic factors: physical/non living factors e.g temperature, rainfall and soil pH

Question 3

How do biotic factors effect ecosystems?

Answer 3

Biotic factors = interactions between organisms involving competition within and between populations e,g food, space, breeding partners

Question 4

How do abiotic factors effect ecosystems?

Answer 4

Light

• Plants need to photosynthesise
• More light = more success of species
• Can adapt by having larger leaves or special photosynthesis pigments

Temperature

• Enzyme activity for metabolism
• Plants and ectothermic animals develop more rapidly
• Animals: can trigger migration/hibernation, Plants: triggers leaf-fall, dormancy + flowering

Water availability

• No water = stress = death
• Plants wilt, no photosynthesis, no turgidity

O2 availability
- suffocation of aquatic organisms/ plants in waterlogged soil

Soil factors

• Clay: fine particles = easily waterlogged = clumps when wet
• Loam: different sized particles = retains water = no waterlogging
• Sandy: coarse/separated particles = retains no water = easily eroded