Topic 8 Revision Questions Flashcards
How does the biosphere regulate the composition of the atmosphere, maintains soil health and regulates water within the hydrological cycle, providing globally import service?
Plants contribute to this when they take up water, decreasing the amount of water that will eventually reach the river and therefore could possibly prevent flooding in the biome.
Animals spread the nutrients around the ecosystem, wether it be through excretion or by the decomposition of their dead bodies into the soil.
Global regional trends increasing demands for food, energy and water resources (population growth, rising affluence, urbanisation and industrialisation)
The global population is increasing and therefore the demand for energy is a lot greater, causing more money to lie in exploiting biomes globally.
Also the increase of the industry (industrialisation) and the technology that goes with it, means that more jobs are available in more condensed areas so more food, water and energy is required to satisfy them and also the energy to be supplied to the new technology and industrial machines.
Malthus Theory
The idea that people will die out when the population becomes too large for the resources.
How are abiotic characteristics interdependent (climate, soil, water, plants, animals, and humans) and how plants and animals are adapted to the climate?
In the tropical rainforest the biodiversity is large and the vegetation is vast meaning those under the canopy level dont get much sunlight and need to adapt using the sun and growth to survive.
In the shrub layer, plants have large dark leaves. Some larger trees have buttress roots to support the drunk and enhance growth (as it can take in more nutrients). Drip tip leaves are curved and pointed so rain can simply pour off of it - preventing any mould to grow. Lianas adapt to climb the emergents (trees which emerge from the canopy) to reach sunlight.
Its not just the plants though, as animals adapt to have strong arms to climb and camouflage to survive from predators in the trees.
Why do tropical rainforests have a high rate of nutrient cycling?
The heat and warm temperature means that decomposition of animals and dead leaves is fast and due to the dense vegetation; nutrients are absorbed quickly allowing for evening faster growth.
Why does the Taiga have low productivity, with a less active nutrient cycle?
The temperature means that decay is slow to occur and any pollution is left in the atmosphere (hindering growth) for decades. The frozen soils means and less dense vegetation means its difficult to absorb nutrients and the shrub layers of animals struggle to eat as they are needles and are very acidic.
How is temperature an indirect threat to the forests?
An increase in temperature creates dry conditions for the soil below. If there isnt enough rain to dampen the conditions of the ground then there is a drought. (Indirectly as a result of hot weather) and this can cause starvation or even fire.
Direct threats to the rainforests through logging
Logging causes large patches of trees to be cut down. This can destroy habitats and food chains that certain animals may rely on. The land is unusable as a habitat for a while, as well as leading to a reduce of interception for rainfall - increasing the risk of flooding.
