Tropical Rainforest Ecosystems Click a button to find

Tropical Rainforest Ecosystems Click a button to find out more

Tropical Rainforest Biome Where are tropical rainforests located? Click a button to find out more Answer Ø Nearly all the tropical rainforest biome is located between Tropic of Cancer (23. 5 o. N), and the Tropic of Capricorn (23. 5 o. S); Ø They are found in South and Central America, Central Africa, South East Asia, Malaysia, Indonesia and North East Australia; Ø Over half of all the tropical rainforests are found in South and Central America. One third of the world’s tropical rainforests are located in Brazil.

Tropical Rainforest Biome What is the climate of the tropical rainforests? Click here for key features of the climate Click a button to find out more Maximum temperatures always around 30 o. C Temperatures hardly change all year round Minimum temperatures not lower than 18 o. C Average temperature range each day is greater than the difference in average temperatures during the year Climate is hot and wet all year Manaus has an average of 171 rainy days per year Heat and rainfall creates high humidity Rainfall year. Many months have very high rainfall totals Drier season Total rainfall in rainforests can be almost four times the amount in London

Tropical Rainforest Biome What is the vegetation like? Click a button to find out more The ecosystem is dominated by broad leaved trees which form a dense canopy layer. A hectare of rainforest may have over 300 species of trees and over 1, 000 species of other plants. The plants have adapted to cope with the environmental conditions in the rainforest. Click here to see how plants have adapted

Tropical Rainforest Biome What is the vegetation like? Click a button to find out more Canopy layer Emergents Leaves Tree trunks Features and adaptations of the vegetation Understorey / Forest floor Roots Biodiversity Lianas & Vines Epiphytes Click on a picture to find out more about the features and adaptations of the vegetation

Tropical Rainforest Biome What is the vegetation like? Canopy Layer Click a button to find out more Higher levels of sunshine allow greater levels of photosynthesis to occur. Canopy layer is over 30 metres above the ground. Hotter and less damp than the forest floor. A dense layer of branches and leaves from the crowns of forest trees. Contains between 60%-90% of rainforest life. The climate means there is no dormant season. Trees can be flowering and fruiting at the same time. Dense foliage blocks 80% of light from reaching forest floor and catches most rain that falls. Click to return to features and adaptations of the vegetation

Tropical Rainforest Biome What is the vegetation like? Emergents Click a button to find out more Crowns of the trees spread to catch as much sunlight as possible. Emergent trees can grow between 40 and 70 metres in height. The emergent layer receives the most sunlight but is affected by the greatest temperature and climate fluctuations as well as strong winds. The diameter of the tree can be as much as 5 metres at the base. The trees often have small, tough leaves to help reduce evaporation and transpiration in the sun. Seeds are often adapted to be blown long distances easily by the strong winds at this level. Click to return to features and adaptations of the vegetation

Tropical Rainforest Biome What is the vegetation like? Leaves Click a button to find out more Leaves have a tough, waxy surface to help shed water to the forest floor. Competition for light means that leaves often grow at different angles to prevent a plant blocking light to its own leaves. Leaves often grow large to catch sunlight. Leaves have pointed tip at the end – a ‘drip tip’. The waxy surface and drip tip allows rainwater to run off easily. This prevents the growth of algae and fungus in the humid conditions which would block the leaves and reduce photosynthesis. Click to return to features and adaptations of the vegetation

Tropical Rainforest Biome What is the vegetation like? Understorey / Forest floor Click a button to find out more Lower levels of the forest and the forest floor are darker and more humid than the canopy layer. Vegetation such as shrubs, ferns and smaller trees are found. These can grow about 4 metres in height. In the darkest parts of the forest the floor is relatively clear of vegetation. Vegetation is thicker near the forest edges and river banks where there is more light. Mangroves can be found by rivers. Click to return to features and adaptations of the vegetation Understorey plants often have large flowers with a strong scent to attract pollinators.

Tropical Rainforest Biome What is the vegetation like? Biodiversity Click a button to find out more 50% of all life found on the world’s land masses is found in tropical rainforests. There may be over 480 different tree species in a single hectare of rainforest. 170, 000 of the known 250, 000 plant species are in rainforests. Any one plant species may not have a large number of individual plants. There is a huge number of animal species especially insects. Biodiversity may be high because the growing conditions allow most species to flourish. Lots of plants of the same species growing close together allows diseases to spread rapidly. Click to return to features and adaptations of the vegetation

Tropical Rainforest Biome What is the vegetation like? Epiphytes Click a button to find out more Epiphytes are plants which grow on other plants. However, unlike a parasite they do not take nutrients from the host tree. Epiphytes get their nutrients from the air, rain, decaying leaves and waste from animals that live on the plants. Click to return to features and adaptations of the vegetation

Tropical Rainforest Biome What is the vegetation like? Lianas and Vines Click a button to find out more Lianas are woody vines. They are rooted in the ground and use other trees to reach the canopy. Once there, they spread out from tree to tree. Some plants start as epiphytes in the canopy and send roots down to the ground to reach the nutrients in the soil. Lianas may be over 1, 000 metres in length. Click to return to features and adaptations of the vegetation

Tropical Rainforest Biome What is the vegetation like? Roots Click a button to find out more Tree roots are often not deep in the ground as the soils are poor and most nutrients are near the surface. Some soils are very shallow. Buttress roots and stilt roots provide the tall trees with support. Buttress roots grow out from the trunk. They can start as high as 5 metres up the trunk. Click to return to features and adaptations of the vegetation

Tropical Rainforest Biome What is the vegetation like? Tree trunks Click a button to find out more Most trees grow tall and straight. There are no branches until the tree reaches the sunlight in the canopy layer where it spreads to catch the light. The bark is often thin and smooth. The bark does not need to be thick to prevent loss of moisture or to protect the tree from cold weather as these are not problems in the rainforest. The bark may be smooth to try and prevent other plants from growing on the tree. Click to return to features and adaptations of the vegetation

Tropical Rainforest Biome The Nutrient Cycle Nutrients are transferred to the ground when leaves and dead organic matter drops to the floor to form leaf litter. Click a button to find out more Biomass Litter As leaf litter decomposes the nutrients enter the soil. Nutrients also enter and leave the cycle at the soil and litter stores. Nutrients stored in the soil are taken up by growing plants and stored in the biomass. Soil Click here to see the nutrient cycle in a tropical rainforest

Tropical Rainforest Biome The Nutrient Cycle in a Tropical Rainforest Nutrients are transferred to the ground when leaves and dead organic matter drops to the floor to form leaf litter. Click a button to find out more Biomass Litter As leaf litter decomposes the nutrients enter the soil. Nutrients also enter and leave the cycle at the soil and litter stores. Nutrients stored in the soil are taken up by growing plants and stored in the biomass. Soil Click here for explanation

Tropical Rainforest Biome The nutrient cycle in a tropical rainforest Click a button to find out more High precipitation adds nutrients to the system. As the plants are always growing, and there is no dormant season when the trees lose their leaves, a large amount of nutrients are stored in the biomass. Litter High levels of runoff wash nutrients from the system. Biomass Some leaves drop during the year. The hot, humid conditions allow rapid decomposition. Leaves can rot in 6 weeks returning lots of nutrients quickly to the soil. High precipitation causes leaching of nutrients from the soil. The number of plants and continual growing season results in high nutrient uptake from the soil to the biomass. Soil Heat and high humidity allows rapid chemical weathering of bedrock, adding nutrients to the soil.

Tropical Rainforest Ecosystems Click a button to find out more
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