Topic 7-People and the Biosphere (paper 3) Flashcards
Ecosystem
All living (biotic) and non-living (abiotic) things in an area and the interactions between them
Biome
Are a large scale global ecosystem with distinctive vegetation and climate
What is the climate and characteristics of a tropical forest?
CLIMATE:climate is same all year round (20-28*),rain fall very high,rains every day (2000mm per year)
CHARACTERISTICS:trees are evergreen,very dense forest,competing for light
What is the climate and characteristics of temperate forests?
CLIMATE:warm summers,cool winters,rain all year round (1500mm) per year
CHARACTERISTICS:deciduous trees (oak-a hard wood with leaves),soil is thick and nutrients rich
What is the climate and characteristics of boreal forests?
CLIMATE:short summers(10),long winters(-20),low rainfall (500mm per year),falls as snow
CHARACTERISTICS:coniferous trees (pine-a soft wood with spikes for leaves)
What is the climate and characteristics of tropical grasslands?
CLIMATE:hot all year (35* the hottest),low rainfall 800-900 per year) but always a dry season
CHARACTERISTICS:tall grasses with some drought adapted shurbs and trees
What is the climate and characteristics of temperate grasslands?
CLIMATE:hot summers (40) and cold winters (-40),250-500mm of rain per year
CHARACTERISTICS:short grasses with minimal trees and bushes
What is the climate and characteristics of a desert?
CLIMATE:hot all year round,with very cold nights,minimal rain fall (less than 2500mm per year)
CHARACTERISTICS:plants are scarce (water storing features-cactus)
What is the climate and characteristics of a tundra?
CLIMATE:low temperatures all year round (0*),low precipitation (250mm per year-most of it snow)
CHARACTERISTICS:not much vegetation,mostly shurbs
What are some factors that affect biome distribution?
ALTITUDE:higher altitudes are colder so fewer plants grow,limits animals.Leads to not much organic matter
DRAINAGE:if its bad soil becomes waterlogged and only aquatics plants and species can survive
SOIL TYPE:nutrient rich which helps support plants,the acidity and drainage also affects how plants can grow
ROCK TYPE:different rocks contain different minerals,some are permeable (water can flow) some are impermeable (water can flow)
What are the biotic components?
These are the living parts of the biome (plants-flora,animals-fauna)
What are the abiotic components?
These are the non-living parts of the biome (soil,water,rock,atmosphere)
How does the biosphere provide for indigenous and local people?
FOOD:they get most of their food directly from plants and animals,or they grow their own
BUILDING MATERIALS:trees and other plants are often used as building materials (houses,furniture),straw can be used for roofs etc
FUEL:indigenous people rely on plants and animals for fuel and cooking and keeping warm
How do humans exploit the biosphere?
ENERGY:as demand is increasing people are using more devices,cars etc,so areas with a high concentration of resources have to be exploited (rainforests etc)
WATER:demand is increasing due to increased population (washing,drink),but they can be overexploited
MINERALS:like gold,iron used in building etc and the demand is increasing leading them to be overexploited
How does the biosphere help regulate gases?+why is it important
-plants take in carbon dioxide and give out oxygen due to photosynthesis
-animals take in oxygen and give out carbon dioxide due to respiration
+can cause global warming,need oxygen to survive
How does the biosphere help the health of the soil?
-plant roots and animals spread nutrients through the soil,maintains soil fertility
-roots can hold soil together,without this it can be eroded
What are the 4 steps in the nutrient cycle?
1.From the soil animals and plants die and decompose,returning nutrients to the soil
2.Plants absorb nutrients from the soil and use them to grow
(3.From step 2 plants drop their leaves which goes into step 1)
4.Animals eat plants,taking in the nutrients they contain
How does the biosphere help regulate the water cycle?
-water is taken up by plants,so less reaches rivers which prevent floods
What is the definition of the nutrient cycle?
This is the way that nutrients move through an ecosystem
What is the definition of the water cycle?
It is the movement of water between land,bodies of water and the atmosphere
What are the 4 steps in the water cycle?
1.Water runs to rivers and the sea
2.Water evaporates
3.Clouds form
4.It rains
How does increasing wealth/urbanisation/industrialisation increase the demand for resources?
INCREASING WEALTH:people have more disposable income so they can buy more things like food,cars etc
URBANISATION:cities tend to be more resource-intensive e.g neon signs use energy
INDUSTRIALISATION:due to more secondary production,more things like factories and more materials are needed
What was the Malthus theory?
-he though the population was increasing faster than the supply of resources,so eventually there were too many people for the resources
-he believed when this happened people will be killed by catastrophes like famine,illness,war until the population could sustain itself
-the point at where lines cross on the graph is the point of catastrophe
What was the Boserup theory?
-her theory was that how ever big the world’s population grew,people would always produce sufficient resources to meet their needs
-things like technological advances in order to avoid problems
