unit 2

Question 1

How do the abiotic and biotic components link in a tropical rainforest ecosystem?

Answer 1

They are liked by energy flow and nutrient cycle.

Question 2

State the trophic levels and names

Answer 2

First - producers ( autotrophs)
2nd - primary consumer ( herbivores)
3rd - Secondary consumer (carnivores)
4th- Tertiary consumer ( Carnivores + Omnivores)

Question 3

How are the energy lost at all stages of the food chain?

Answer 3

respiration and excretion

Question 4

Explain the 10 percent law

Answer 4

Only 10% of the energy from one trophic level can pass to the next higher level because some food are not edible and some parts of the food cannot be digested, some are consumed for growth and repair.

Question 5

Can there be many trophic levels

Answer 5

no, because the energy flow is insufficient to support many levels of food chain.

Question 6

Explain the nutrient cycling

Answer 6

nutrients are inorganic substances, air and rainfall provides nutrients. plants turn the inorganic substance into organic matter, when they die, organic matter and decomposed into inorganic nutrients

Question 7

Nutrient cycle: where are nutrients stored in biomass?

Answer 7

stored in plant tissue that are produced by photosynthesis using solar energy.
also stored in animal tissues.

Question 8

Nutrient cycle: where are the nutrient stored/ flow in litter

Answer 8

From dead plant materials, animal wastes
dissolved nutrients from falling rain

Question 9

Nutrient cycle: where are the nutrient stored. flow in soil?

Answer 9

broken down from decomposed litter and weathered rocks

Question 10

Why is the nutrient storage in biomass huge?

Answer 10

• under high temperature
• year long growing season
• vegetation dense
• supports large number of animals
• rapid and dense vegetation results in strong littering

Question 11

Why is the storage in soil small?

Answer 11

although active decomposition, weathering supply a lot of nutrients.
- rain leads to intense leaching
- rapid vegetation growth, dense vegetation quickly absorb soil nutrients

Question 12

Why is the storage in litter small

Answer 12

• hot and wet climate favours decomposition , litter quickly broken down into soil nutrients
• surface runoff washes away a lot of litter

Question 13

Why is the TRF a complex ecosystem?

Answer 13

high biodiversity
diverse habitats
high density of species with relatively small plot of land

Question 14

What is the definition of resistance stability of the ecosystem?

Answer 14

an ecosystem’s ability to withstand disturbance and maintain its current status

Question 15

What is the definition of resilience stability of ecosystem?

Answer 15

an ecosystem’s ability to restore to its previous state after disturbance

Question 16

When does the ecosystem becomes fragile?
When does the resistance stability increase?

Answer 16

When facing large-scale destructions (deforestation and fire)
rainforest’s high resistance stability is only limited to small-scale disturbance
- it increases with increasing complexity of the ecosystem when disturbance is in small scale.

Question 17

What 3 main activities are the cause of deforestation?

Answer 17

agricultural development
resource extraction
urban development

Question 18

explain the process of shifting cultivation and how it leads to deforestation

Question 19

Explain sedentary farming

Question 20

Explain plantations

Question 21

Explain livestock rearing and how it leads to deforestation

Question 22

list the resources extraction, firewood, timber, hydro-electric power, minerals

Question 23

Explain urban development

Question 24

why are tropical rainforest disappearing at a faster rate today than the past?

Answer 24

1. growing population
2. rising living standards
3. foreign debts
4. poverty
5. political instability

Question 24

Toursim

Question 25

Environmental impact of deforestation in local.
Local climate (atmosphere)
biosphere
hydrosphere
energy flow and nutrient cycling

Question 26

Environmental impact of deforestation on global scale

Answer 26

1. enhance global warming
2. altering global rainfall pattern
3. inducing climate change