Cold - KQ2 (why fragile) Flashcards
1
Q
What are factors affecting plant productivity?
A
- High wind speed = rapid transpiration
- Extreme cold = no photosynthesis can occur
- Polar night = no photosynthesis
- Snow cover for months at a time = coil is frozen or partly frozen (permafrost) = no liquid so hydrological drought
- Few soil organisms to break down organic matter = no nutrients for plants
- Low rainfall = few nutrients (which are in rainfall) and not much downward movement of water bedrock (plants need water for growth)
2
Q
What are plants that are adapted?
A
- Prostrate (low lying) shrub = insulate beneath snow
- Dormant/pre-formed plant flower = maximum time for seed production
- Hummock shaped plants = shape conserves energy (7*C warmer than air temperature)
- Cushion plants = low lying plant close to ground surface = reduces impact of wind speed on water loss
3
Q
What are plant adaptations?
A
- Hairy leaves (protection and insulation)
- Optimum photosynthesis rate lower than most plants
- Leaves close at night
- Optimise available solar radiation
- No/minial rooting
- Frost resistance (can survive low temperatures)
- Longevity (live for a long time)
4
Q
How are animals adapted to life in cold environments?
A
- Very few species
- Large numbers of single species (eg Caribou, lemmings)
- Population numbers are very cylical
5
Q
What are animal adaptations?
A
- Low number of species
- Fur insulation
- Increased metabolic rates
- Live below snow patch (small animals)
- Birds migrate
- Breeding cycle compressed
- Simple food chain
- Large litter size
- White fur (camouflage)
- Insulation with lots of fur
- Greasy coat (sheds water after swimming = not as cold)
6
Q
What is the nutrient cycle in cold environments?
A
- Essential for plant growth but stopped by many factors in cold environments
- Weathering rate is slow = amount of nutrients in soil is limited
- Precipitation is low = few nutrients dissolved in rainwater
- Snow makes it difficult for plant roots to reach and absorb limited supply of nutrients
