Population And Resources Flashcards
Population growth and resource balance
. Optimum population- the ideal number of people in an area low dependancy ratio and technology improves
. Overpopulation- population is too high for available resources = the standing of living falls
. Under population- population is too low so there are too few people to use resources to their full potential =standard of living falls
Carrying capacity
. The largest population of an area that is capable in supporting in the long term
Changes in responses with carrying capacity
. As a slow growing population reaches a resource limit, the growth rate may decrease ( population size becomes stable)
. If population growth grows very rapidly, it May overshoot the resource limit. The population may fall suddenly as death rates increase e.g. during famine, the population may fluctuate around the carrying capacity before stabilising
Ecological footprint
. Measure environmental impact of human activities
. Calculating the amount of productive land to produce goods and services
. Measured in global hectares (gha)
Ecological footprints can measure the impact of population growth
. As Ecological footprint increases, the carrying capacity decreases ( if more resources are required per person, the environment can not support the required people )
. Developed countries have larger ecological footprint that developing countries
. Due to current rate of consumption, the world population uses the equivalent of 1.6 earths- this means that the earth takes more than a year and a half to regenerate the resources that humans use in a year
The PRP Model ( population, resources and pollution model)
. Shows relationship between people and the environment
Positive feedback
. Population growth lead to a need for more food which drives an increase in food production.the availability of food allows the population to grow further. This leads to further drive to improve yields which leads to an even higher food availability, which leads to more population growth
. An increased population results in more extraction of fossil fuels , so more fuel is available to transport food where there are shortages. This decreases malnutrition and allows the population to increase
Negative feedback
. Growing populations cause expansion of agriculture which leads to increase of soil erosion. This decreases agricultural yields as soil becomes less fertile. Good production is no longer high enough to support the population
. Increased population= increased extraction of fossil fuel . Increase level of greenhouse gases from combustion cause climate change which reduces rainfall and crop yields in some areas. This causes malnutrition, which reduces the population
Malthus
. When population increases to the point where there are too many people for the food available. The population size will be reduced by events such as famine, war and disease- population will exceed the carrying capacity and death rates will increase
. One problem with this theory is that rate of growth in food production can’t increase which is false- it increased in the 18th century due to technological examples
Neo Malthusian
. Population increasing faster than resource production rates
. Argue that rapid population growth should be slowed down e.g reducing birth rates through contraception
Boserup
. Population growth encouraged new methods of technology
. Increase food production through genetic modification
. It is uncertain the food production will keep up with growing population in the future
Simon
. Growing population increased intelligent individuals to solve problems- resources wouldn’t run out
. Human innovation will fix future problems
. Natural resources can be found in different ways but there is criticism to this: conditions in some countries may have gotten worse due to climate change
