Hot deserts

Question 1

Describe characteristics of a hot desert.

Answer 1

Very little rainfall 250mm per year.
rain varies alot - once every two years
extreme temperatures- 45 degress at day 5 degrees at night

soil is shallow coarse gravel texture
no leaf fall - soil is infertile
lack of rainfall and plant material -soil is dry.

Plant growth is sparse due to less rainfaill
only cact aind thornbushes grow
plants are short
planats have a short life cycle

Losts of scorpions, insects and snakes and lizards
mammals are small and nocturnal eg.kangaroo rats
birds leave because of harsh environment
roadrunners can live there all year round.

Many people living in dessert grow a few crops in desert fringes

indiginous people are often normadic- move around in search for food and water-mostly sheeps and goats.

Question 2

Are deserts an interdependant ecosystem?

Answer 2

Yes biotic factors and abiotic factors are reated closely and if one changes the others are affected.

Question 3

Describe interdependance of climate,water,soil,plants,animals

Answer 3

Plants gain nutrients from soil- provide nutrients and water for animals that feed on them.
animals will spread seeds through their dung for plants to reproduce.

Plants struggle to grow- soil is infertile and dry and low in nutrients.
little decomposition of dead plant.

sparse vegeation can only support dense population of animals.

water is scarce- rainfall quickly drains away
animals and people move or dig deep wells.

people have to irrigate to water plants. this allows for water underground to decrease and available to plants. some animals ad plants struggle to survive.

overgrazing vegetation( changing components of ecosystem) can cause soil erosion. no plants to stabilise soil fine soil particles blown away.

soil erosion clouds of dust- changing climate reducing rainfall make it drier.

Question 4

What is desertification?

Answer 4

degradation of land. becomes drier less productive.

Question 5

what causes desertification?

Answer 5

climate change- rainfall, temperatures

human activities- removal of fuel for wood.
overgrazing, overcultivation, population growth.

Question 6

How to reduce desertification?

Answer 6

water mangement
plating trees
soil management
appropiate technology

Question 7

Describe plant adaptations

Answer 7

Long plant roots to absorb deep water- spread out wide to absorb much water as possible from rain

Cacti- thick waxy skin to reduce water loss
large fleshy stems to store water.
sharp spines to protect itself from animals stealing water.

plants- small leaves/spines to reduce transpiration (small surface area)