population and environment Flashcards
what is the size of a population influenced by
how many people the environment of that area can support
Define population distribution
pattern of where people live
Give an example of uneven population distribution
In China over 90% of the population live in the Eastern part of the country due to much of the Western area bein unhabitable due to mountains and desert
Define population density
The population of an area divided by the size of that area/ number of people per square kilometre
Where are the areas of highest population density located?
South and East Asia
What prevented population rise
Famine disease war
Why has population increased since 1950
Improvements in medicine and food production
increased life expectancy and reduced infant mortality
What three physical aspects affect populations
climate
soils
resource ditribution
describe how climate has an affect on population size
few people live in arid areas such as the Sahar, but many live in temperate climates such as the UK
Tropical and temperate climates usually have the highest population sizes and densities due to ability to produce food
How will climate change affect population size in the future
It can affect population distribution, for example in coastal areas where sea levels are rising people are moving inland or even abandoning their islands
It is also causing levels of nutrition to fall in some countries
How does soil affect population
Soil fertility determines the amount and types of food that can be produced in a region and has played a role in determining where human settlements have developed
Soil erosion can cause people to migrate to other places as agriculture becomes difficult
some examples of how soil has affected populations
Naples is built near a volcano where soil fertility is high
Bangladesh have large floodplains which are very fertile so it can support large scale agriculture and feed the large population
Describe how resource distribution can affect populations
Population growth and density is linked to availability of fresh water and other resources - most deserts have small populations because of lack of water
lack of safe water can lead to food insecurity causing populations to decrease
Places with a lot of naturally occurring food and fuel are able to support fairly large populations
Give examples of revolutions that have affected population size and distribution
neolithic revolution
industrial revolution
Describe the neolithic revolution
the development of agriculture and shift from hunting and gathering to farming and permanent settlements
this caused populations to increase as food supply become more reliable
Describe the industrial revolution and its impacts
1760-1850
rapid rise in the use of machinery and factories in developed countries and coincided with population growth
e.g. Britains population more than doubled - death rates fell because of increased food production and higher incomes so people had better diets
How has global food production changed over the last 50 years
the area of agricultural land has increased as well as technological advances such as irrigation and pesticides have made it possible to produce more food from less land
What is the pattern of global cereal production
Most is produced in N.America, China and Brazil - temperate climates and countries which have enough money to invest in agriculture
Why do East Asia and North America produce a lot of food
Climates that are good for farming
lots of investment into agriculture
Why do Central America and Africa produce relatively small amounts of food
Lack of resources and funding
large areas of land unsuitable for farmins- desert
Unsuitable climates
How has global food consumption changed
More food is being consumed worldwide as population increases and countries become more economically developed
Describe global food consumption
More developed areas like North America and Europe consume a lot as they can afford to import a large variety of foods and have a culture of cu=consumerism as well as the majority of the population having a large disposable income - up to 3539kcal
Less developed areas Such as Africa S.A and Asia consume less in sub -Saharan Africa less than 2546 kcal
How does the type of food consumed vary between countries
Meat costs more t produce than plant-based food so it makes up a bigger proportion of the diet in developed countries
meat consumption 2020
USA - 149kg per capita
Ethiopia -8.3kg per capita
What kind of systems are farms
Open systems as energy and matter can be lost or gained from the environment