3.1.1-.2 Human Pop Growth. Human population growth. This question is difficult to answer. Estimates are usually based on food, but human agriculture limits assumptions on available amounts. Human population growth rate has been growing more than exponentially. .
3.1.1-.2 Human Pop Growth
This question is difficult to answer.
What is the carrying capacity of Earth for humans?
domestication of plants, animals 9000 B.C. (about 11,000 years ago)
agriculturally based urban societies
beginning of industrial, scientific revolutions
HUMAN POPULATION GROWTH
The availability of food and water
Invasion of parasites, pathogens, or disease
Severe or sudden climatic changes
Pollution of air, soil and water
If we do not take steps to control human population growth, it is likely that one or more of these growth-limitingfactors will eventually kick in to forcibly reduce our numbers.
Crude birth rate = the number of births per thousand individuals in a population per year.
Crude death rate = the number of deaths per thousand individuals in a population per year.
Fertility = the potential of reproduction exhibited in a population.
Natural increase rate = the form in which human population growth rates are usually expressed
Crude birth rate – crude death rate
Human Population growth = 1.4% per year
Developing nations = 1.7%
Developed nations = 1.0%
Doubling time (T) = 70 .
annual percentage rate (g)
Doubling time = the number of years it would take a population to double its size at its current growth rate.
Doubling time (T) = 70 . = 50 years