The living world - Tropical Rainforests and Ecosystems Flashcards
Definition of an ecosystem
The living organisms in a particular area, together with the non-living components of the environment.
Producer
A producer is an organism that uses sunlight energy to produce food
Consumer
A consumer is an organism that gets its energy by eating other organisms, either producers or other consumers
Decomposer
A decomposer is an organism that gets it’s energy by breaking down dead material.
Bacteria and fungi are decomposers.
Example of a small scale ecosystem
Epping forest, Essex
Key features of Epping forest
-700 species of fungi
-Many insects, amphibians and birds
-Many mammals
-Producers made from grass, bracken and brambles
How do people impact the ecosystem of Epping forst
-Visitors pick fruit and berries, helping to disperse seeds.
-Many trees cut down for timber
-Initially a hunting forest, now used for recreation and conservation
How do the soil/plants/animals change throughout the seasons (Epping forest)
Spring- Stored nutrients are used by the growing of plants to produce fruit, berries and nuts that will feed consumers.
Summer- Leaves grow increasing surface area maximizing rate of photosynthesis.
Autumn - Trees shed leaves to consume energy + moisture
Definition of biome
A large scale ecosystem
6 types of ecosystems
Tundra/Polar
Tropical rainforest
Hot desert
Coniferous forest
Deciduous forest
Grassland
Location of hot deserts
30N and 30S of the equator, between the tropics.
Characteristics of hot deserts
Sinking air suppresses rain formation leading to avid conditions.
Hot in the daytime but cooler at night due to the lack of cloud cover allowing heat to escape quicker.
Location and distribution of Tropical Rainforest
Close to the equator, widespread across Asia, Africa and South America
Covers 2% of the Earth’s surface but contains over half of the world’s plants and animals.
Climate of TR
High temp (27C) throughout the year
High rainfall (2000m a year)
Ideal conditions for lush vegetation growth
Water in Tropical Rainforests
Most TRs experience a distinct wet season, with rainfall lasting for several months
Soil in TRs
Rainforest soils are not very fertile. Nutrients are concentrated in the upper top soil and are very quickly taken up by the plants as they grow.
People in TRs
-Traditional tribes live in harmony with natural environment
-However people exploit tropical rainforests for commercial gain (Timber or for plantations)
Plants and animals in TRs
Rainforests have the highest level of biodiversity in the world
Birds live in the canopy, snakes use the trunk of trees as “Vertical highways”
Mammals are well adapted to life in the trees.
How do plants adapt to tropical rainforest conditions
-Emergent trees grow taller in order to absorb more sunlight through the canopy.
-Trees have buttress roots to help anchor the trees in the shallow rainforest soil.
How do people rely on plants and animals in tropical rainforests
-Traditional tribes use plants and animals in order to survive
-Trees cut down for timer and resources.
How do animals adapt to the characteristics of Tropical Rainforests
-Intense competition for food, animals have become adapted to live off specific plants or animals that few others eat.
-Animals also adapt by having physical features that they can benefit from, such as the three-toed sloth, can swim in floods and has green algae in fur to camouflage
-Therefore higher chance of survival in conditions.
Social Value of TR
-25% of all medicines come from rainforest plants and more than 8000 plants have anti-cancer properties.
-Traditional tribes
-High rainfall totals in rainforests create the potential for hydro-electric power
Economic value of TR
Employment opportunities in tourism sector as a guide etc.
-Farming, mining, construction job opportunities
Environmental value of TR
-Biodiversity - more than 50% of Earth’s plants and animals
-Rainforests are important sources of freshwater (20% of the world’s freshwater is from amazon basin)
-Rainforests absorb co2 acting as a ‘carbon sink’
Suggest why rates of deforestation vary
Government priorities - economic growth
-Limited economic options
Case study for tropical rainforests
Amazon rain forest - causes of deforestation
Causes of deforestation (case study)
-Rapid population growth, demand for food and housing
-globalized food network
-Demand for goods
Info about cattle farming in the amazon
-It is an unsustainable activity as the quality of the pasture constantly changes
-Lots of beef is exported from Brazil and sold causing economic growth
Info about commercial farming in the amazon
-Forest is being used to grow crops such as bananas, palm oil, pineapple, sugar cane etc.
-Amount of rainforest cleared by this doubled between 1990 & 2010 (deforestation)
-Cultivation of crops
Info about small scale agriculture in the amazon
Local people growing crops on their own land, causing population growth and settlements being built on deforested land.
info about logging in the amazon
-mahogany is sold to other countries to make furniture (selective logging). Smaller trees are often used as wood for fuel or made into pulp or charcoal.
Info about mineral extraction in the amazon
-Gold mining in La Pampa, Peru
-This requires the removal of all trees within the mining area.
-Low quality soil
-leads to settlement growth
Info about energy development in the amazon
-Heavy rainfall and unlimited supply of water has caused dams to be built for hydroelectric power
Describe what the ‘modern gold rush is’
-Gold being discovered in areas are causing people to flee to those areas to make money quickly.
Name 2 causes of deforestation that are linked:
Mineral extraction and growth as when gold is discovered through mineral extraction, people migrate to those areas for economic benefit.
IMPACTS of deforestation:
-Local climate change, can affect rainfall patterns regionally
-Soil erosion and fertility, leads to increased flood risk
-River pollution, Mercury leaks into water affecting human health and death of animals
-Decline of indigenous tribes, changing their way of life in the long term
-Climate change, rainforest turns from a carbon sink to a carbon source, leading to rising sea levels.
