Ecosystems

• What is an ecosystem?

  A community of living organisms interacting with each other and their physical environment
• What are the biotic and abiotic components of an ecosystem?

  • Biotic = living (plants, animals, bacteria)
  • Abiotic = non-living (climate, soil, water, light, temperature).
• What is the difference between a food chain and a food web?

  • Food chain = A simple flow of energy between organisms.
  • Food web = Multiple interconnected food chains showing complex energy transfers.
• What are producers, consumers, and decomposers?

  • Producers (e.g., plants) make their own food via photosynthesis.
  • Consumers (e.g., herbivores, carnivores) eat other organisms.
  • Decomposers (e.g., fungi, bacteria) break down dead matter and recycle nutrients
• What is litter in the nutrient cycle?

  Dead organic material (e.g., leaves, dead animals). Decomposes quickly in warm, humid conditions.
• What is biomass in an ecosystem?

  All living things in the ecosystem, including plants and animals.
• How is soil formed in an ecosystem?

  Developed by mixing dead organic matter with weathered bedrock
• What is leaching in the nutrient cycle?

  Loss of nutrients from the soil, often due to heavy rainfall.
• What is runoff in an ecosystem?

  The draining away of nutrients in water from rainfall.
• How do nutrients move from biomass to litter?

  When plants and animals die, nutrients fall to the ground and enter the litter store
• How do nutrients move from litter to soil?

  Decomposers break down dead organic material, releasing nutrients into the soil.
• How do plants obtain nutrients from the soil?

  Plants absorb nutrients that are dissolved in soil water.
• What is the role of decomposers in the nutrient cycle?

  They break down dead matter, releasing nutrients back into the soil.
• How does weathered rock contribute to the nutrient cycle?

  Weathered rock adds minerals to the soil, supporting plant growth.
• What is a small-scale ecosystem?

  A local ecosystem that includes biotic (living) and abiotic (non-living) components interacting in a small area, such as a pond.
• Why is a pond considered an ecosystem?

  It has a variety of organisms (plants, animals, decomposers) interacting with non-living factors like water, sunlight, and soil.
• What are the main components of a pond ecosystem?

  • Producers (plants)
  • Consumers (insects, fish, birds)
  • Decomposers (bacteria, fungi)
  • Abiotic factors (water, soil, sunlight).
• Give an example of a producer in a pond ecosystem.

  Algae and pondweed are producers as they photosynthesize to make their own food
• What are primary consumers in a pond ecosystem?

  Small herbivores like water snails and tadpoles that feed on plants and algae.
• What are secondary consumers in a pond ecosystem?

  Carnivores such as dragonfly larvae and small fish that eat primary consumers.
• What are tertiary consumers in a pond ecosystem?

  Top predators like herons and large fish that feed on secondary consumers.
• What is the role of decomposers in a pond ecosystem?

  Bacteria and fungi break down dead plants and animals, returning nutrients to the water and soil.
• How does the nutrient cycle work in a pond?

  Plants absorb nutrients from the water, consumers eat plants and other organisms, decomposers recycle nutrients back into the ecosystem.
• What happens if one component of a pond ecosystem is disrupted?

  A knock-on effect occurs. For example, if fish are removed, insect populations may increase, affecting plant life and nutrient cycling.
• How does seasonality affect a pond ecosystem?

  • In summer, more sunlight leads to increased plant growth.
  • In winter, cold temperatures slow down decomposition and plant growth.
• How do humans impact pond ecosystems?

  Pollution, eutrophication (excess nutrients causing algae blooms), and draining ponds for development can damage the ecosystem.
• What is a biome?

  A large scale ecosystem
• What are biome characteristics defined by and what are different biomes known by?

  • Characteristics defined by ABIOTIC factors
  • Different biomes are known by their dominant type of VEGETATION
• Name examples of global biomes:

  •  Tropical Rainforest 
  • Hot Desert 
  • Polar region 
  • Tropical Grassland (Savana)  
  • Tundra 
• Describe where tropical rainforests are found and why, and its key features:


  Location:

  • Located near the Equator, between the Tropics of Cancer and Capricorn, in regions like the Amazon, Congo, and Southeast Asia
  • The sun’s rays are concentrated at this latitude heating moist air which rises and creates convectional rainfall.

  Key Features:

  • Hot, humid and wet all year round (ideal for plant growth)
  • More than 50% of worlds biodiversity found here

  
• Describe where hot deserts are found and why, and its key features:

  Location

  • Found in dry, subtropical regions near the Tropics of Cancer and Capricorn is Africa, Asia etc
  • Cool sinking air causes high pressure and prevents clouds from forming
  • This leads to high daytime temperatures, low nighttime temperatures and low rainfall

  Key Features:

  • Hot and dry during the day but cold at night
  • Low rainfall means lack of plants and animals

  
• Describe where polar regions are found and why, and its key features:

  Location

  • Located in the Arctic (North Pole) and Antarctica (South Pole)
  • Cold air sinks at the north and south poles resulting in very low temperatures and dry conditions
  • In winter it is dark and temperatures can fall below -50°C

  Key Features

  • Extremely low temperatures (often below freezing) with dry air
  • Few plants and animals can survive

  
• Describe where tundras are found and why, and its key features:

  Location

  • Found in the far north of North America, Europe, and Asia
  • The sun’s rays have very little strength/concentration due to the curve of the earth so temperatures are below freezing for most of the year

  Key Features

  • Cold, windy and dry in the winter
  • Low-growing plants and mosses
  • Permafrost- frozen soil

  
• Describe where deciduous and coniferous forests are found and why, and its key features:

  Location

  • Deciduous forests are found in temperate regions mainly in the mid-latitudes. Coniferous forests (Taiga) are located in cold northern regions just below the tundra
  • Rain bearing storms arrive regularly due to frontal rainfall (where a warm mass of
  • air meets a cold mass of air)
  • Ideal growing conditions for forests

  Key Features:

  • Temperate climates
  • Deciduous- shed leaves in the winter
  • Coniferous- evergreen

  
• Describe where savannas are found and why, and its key features:

  Location

  • Found in warm regions between tropical rainforests and deserts, mainly in central areas of continents with seasonal rainfall
  • Predominantly dry with distinct wet and dry seasons that bring thunderstorms and wildfires
  • Conditions are dry for half of the year due to the seasonal movement of the Hadley cell

  Key Features

  • Hot during dry season and prone to fires
  • Large heards of animals found here