Exam style questions on ecosystems

found online

state one role of decomposers in an ecosystem

-help return nutrients to the soil

give 2 reasons why the biomass changes between each level in a food chain

-loss of energy through respiration

-loss of energy through movement

What are the roles of producers in an ecosystem?

organisms that produce their own food

Outline one possible environmental impact of deforestation

-forest habitats are destroyed:leading to reduction and possible decimation of species

Suggest one way that international co-operation can help make tropical rainforests more sustainable

countries can be relieved of some of their debt, known as debt for nature schemes in return for retaining their rainforest areas.

Development like mining (seen in Figure 8) brings economic benefits — big investment , creates jobs and improves roads & communication, boosting local economy.

But it damages the environment — deforestation causes soil erosion forming gullies and polluting rivers, which harms ecosystems and people.

Explain how either international hardwood agreements or selective logging can encourage the sustainable management of tropical rainforests.

The International Tropical Timber Agreement ensures that wood from tropical areas is legally sourced/sustainable

Give one effect of deforestation on the soils of the rainforest

they become less fertile

State one way that debt reduction can help to make tropical rainforests more sustainable.

countries are relieved of some of their debt in return for protecting their rainforests

-The ecotourism development seems to be small scale, making little impact on the rainforest.

outline one reason for the distirbution of the tropical rainforest

-rainforest areas all have high humidity/high rainfall

-this means they have a continuous growing season

outline one reason why nutrient cycling is very rapid in tropical rainforest

the hot damp ,conditions allow for the rapid decomposition of dead plant material

-Competition for sunlight in the rainforest means that trees are very tall with emergents being the tallest .

-The tall trees have buttress roots, which help to support them.

-Many plants have waxy leaves with drip tips, which allow water to run off them so that they don't break or go moldy.

• Hot temps = year-round growth & sunlight competition

• 💧 Rainfall + humidity = rapid tall tree growth

• ☀ Only 2% light on forest floor = only shade-adapted plants survive

• 🌳 Buttress roots support tall trees (Figure 6)

• 🌿 Dense undergrowth in light gaps (swamps, rivers, clearings)

• 🌱 Named adaptations: lianas (climb trees), epiphytes (live in canopy

Evidence (E):

• Cacti have spines instead of leaves and a thick waxy skin.

• Cacti can store water.

• Camels have large flat feet and fatty humps for energy.

  Understanding (U):

  • Spines and waxy skin help reduce water loss.

  • Storing water helps plants survive long dry periods.

  • Camels can survive without food and water for long periods due to fat stores and water conservation.