Paper 3 - People and The Biosphere - Topic 7 Flashcards
What is the biosphere?
The biosphere is the living layer of earth
What is the biosphere between ?
The rocks (lithosphere) and air (atmosphere)
What is found in the biosphere ?
All plants and animals
What are the large regions that the biosphere is divided into called ?
Biomes
What is a biome ?
A large scale ecosystem with a distinc climate
What are the 9 main biomes ?
Tundra Boreal forest (taiga) Temperate deciduous forest Temperate grassland Mediterranean Hot desert Tropical rainforest Tropical grassland (savanna) Other biomes (Ice,mountains)
What is the vegetation like for the tundra ?
Grasses, lichens and dwarf shrubs; no trees
What is the vegetation like for the boreal forests (taiga) ?
Coniferous trees, e.g.pine
What is the vegetation like for the temperate deciduous forest ?
Deciduous trees, e.g. oak
What is the vegetation like for the temperate grassland?
Short or tall grasses with few trees
What is the vegetation like for the Mediterranean?
Evergreen and deciduous trees and shrubs
What is the vegetation like for the hot desert ?
Cacti and succulents, but few of them
What is the vegetation like for the tropical rainforest ?
Evergreen trees growing all year round
What is the vegetation like for the tropical grassland (savanna) ?
Grass with some trees, e.g. acacia
How are the biomes distributed ?
In belts around the earth at different latitudes
What does latitude measure ?
How far north or south a location on the earths surface is from the equator
What is the location and characteristics of each biome determined by ?
Climate because it affects the growth of plants
How does temperature affect the growth of plants ?
Most plants need over 5 degrees Celsius to grow
How does precipitation affect the growth of plants ?
Plants need water to grow
How does light intensity affect the growth of plants ?
Affects photosynthesis so therefore plants cant grow as well
How does latitude influence biomes ?
Because latitude controls light intensity, temperature and precipitation
If the UK was totally natural what biome would we have ?
Temperature forest biome
What are local factors ?
Differences that alter animal and plant species in a biome from once we would expect
What are ecosystems ?
Localised biomes
If the UK was totally natural what 3 local factors would affect our biome ?
Rock and soil type
Water availability and drainage
Altitude
How would our Rock and soil type affect our biome ?
When rocks undergo chemical weathering, they release nutrients and chemicals into the soil. Soils can be neutral, acid or alkaline depending on the rock type.
The acidity or alkalinity of the soil will affect what can grow there.
How would our Water availability and drainage type affect our biome ?
Some plants can grow their roots in waterlogged and boggy soils.
Other plants grow in drier soils
The amount of precipitation affects the soil of an area
The amount of evaporation affect soil of an area
How permeable the soil is affects the soil of an area
How would our altitude affect our biome ?
Temperature drops 6.5 degrees Celsius every 1000m increase in height
At high altitudes below freezing temperatures limits what plants can grow
At high altitudes high precipitation often follows
What is altitudinal zonation ?
The change in ecosystems at different altitudes caused by alterations in temperature, precipitation, sunlight and soil type
What height is tree line ?
4000m it becomes too cold for trees to grow
What are the two parts that biomes are made of ?
Biotic and abiotic
What is the biotic part of a biome ?
The Biotic (living) part is made up of plant (flora) and animal (fauna) life
What is the abiotic part of a biome ?
The abiotic (non-living) part includes the atmosphere, water, rock and soil
Are dead animal and plants biotic or abiotic ?
Biotic as they were once living
How are biotic and abiotic parts linked ?
1 . Energy is provied for photosythesis of plants. This is provided by the suns energy
- Plants take in carbon dioxide from the atmosphere and release oxygen
Animals take in oxygen and release carbon dioxide into the atmosphere
Nitrogen is exchanged between the atmosphere, plants and soil - Energy flows along the food web from plants - herbivours - carnivores - detritivours and decomposers which consume dead plants and animals
- Water moves through the soil, plants and animals and then is released back into atmosphere via respiration and evaporation
- When plants and animals die they decompose into the soil
- Weathering of rocks provides soil nutrients - magnesium, nitrogen
Why are places like the rainforest making 4-6 trillion dollers per year ?
As they provide goods and services
What are goods ?
Physical materials - timber from trees or fish
What are services ?
Functions that can make a benefit - add trees for more oxygen
What are the 4 catagories of ecosystem services ?
Provisioning services (goods)
Regulating services
Supporting services
Cultural services
What are an ecosystem’s provisioning services (goods) ?
Products obtained from the ecosystem
Food - nuts, berries, fish, crops
Fuel wood
Timber for buildings and other uses
Genetic and chemcial material
What are the ecosystem’s regulating services ?
Services that link to other physical systems and keep areas and the whole planet, healthy
Storing carbon, and keeps emitting oxygen, which keeps the atmosphere in balance
What are an ecosystem’s supporting services ?
These keep the ecosystem healthy so it can provide other services :
Nutrients
Photosythesis and food webs
Soil formation
What are an ecosystem’s cultural services ?
These are benefits people get from visiting, or living in, a healthy ecosystem:
Recreation
Education and science
Spiritual well-being and happiness
What is the role of an ecosystem ?
Maintaining a healthy atmosphere
- trees taking in carbon dioxide act as a carbon sink
What are indigenous people ?
the original/native people of a region
what is one example of the indigenous people ?
Efe people of the ituri tropical rainforest in the Congo basin of Africa
How many Efe people are there today ?
around 30000
How do the Efe people use the rainforest ecosystem for services to benefit them ?
use wood and leaves to make their houses
use the wood from the forest to cook
gather wild yams, mushrooms and berries to eat from the forest
hunt monkey and antelope for bushmeat and also fish from rivers
hunt the giant forest hog and sell its meat to other people in the region
buy or trade items like pans or rice
use plants and wild honey to make traditional medicines
Why are the Efe peoples houses small circular and built out of wood and leaves ?
houses are small circular and built out of wood and leaves - these are temporary as they move around the forest to hunt
define ecosystem services
the collective term for all the ways humans benefit from ecosystems
how does slash and burn aka shifting cultivation work ?
Farmers clear small areas of forest by cutting and burning
the ash from burning adds nutrients to the soil
the land is then farmed for 5-6 years, but after that the soil becomes infertile and farmers move to the next area of land
what percentage of the taiga is destroyed by human activity ?
around 7%
what percentage of rainforests are destroyed by human activity ?
about 17%
what percentage of temperate grassland is destroyed by human activity ?
about 67%
what percentage of temperate forest is destroyed by temperate forest ?
about 73%
what are some reasons that large are biomes cleared ?
commercial farming - for cattle ranching or to grow food like soy beans to be fed to cattle
commercial crops - palm oil, cocoa beans or cereals
mining metal ores - iron and copper
deforestation - timber wood to make paper or furniture
construction of dams and reservoirs for HEP and water supply to cities
what is the problem for biomes once they have been cleared ?
cant grow back
what are the benefits of commercial exploitation ?
provides profits for TNC’s
jobs are provided for people
good income for government
what are the negatives/drawbacks of commercial exploitation ?
many ecosystem services are destroyed
the areas that were once forest can no longer store carbon, prevent flooding or be used for recreation
what do humans depend on our biomes for ?
preventing flooding
regulation of carbon dioxide levels
keeping soil healthy to grow crops
perform the hydrological cycle so we have clean water
what are carbon sinks ?
natural stores for carbon containing chemical compounds like carbon dioxide(CO2) or methane (CH4)
what is carbon sequestration ?
something storing carbon by removing carbon dioxide from the atmosphere and locking it up in biotic material
what is the process of photosynthesis ?
carbon dioxide + water + (sunlight) –> glucose + oxygen
how do biomes store carbon ?
As biomass (leaves,branches,trunks,roots and animal tissue)
when plants and animals die the dead biomass ends up in the soil.
what does this make the soil
an important carbon sink
how much carbon do biomes on land absorb per year ?
120 billion tonnes
what are ways that more carbon can end up in our atmosphere ?
Humans destroy biomes - through deforestation so biomes cant absorb as carbon dioxide
biomass such as trees are burned, and soil destroyed, releasing their stored carbon
Nutrients cycle 1
Ans
N
A
N
A
N
A
What was the veiw of thomas malthus ?
Pessimistic - population will eventually grow so large that the planet will run out of food, water and energy and other resources, leading to crisis
What was the veiw of Ester Boserup ?
Optimistic - As population grows, humans invent new technologies to allow more food to be grown, and more resources to be supplied
