Average age an infant can expect to reach in any given society
Crude Death Rate
Number of deaths per thousand people in any given year
Crude Birth rate
Number of births per year per thousand
Total Fertility Rate
Total children born to an average women during her lifetime
Population growth equation
Population (t) = population (t-1)*e(k*t) : population at some later time (t) = population at an earlier time (t-1) * 2.718(growth rate*time) You can guess at a doubling time by 70/R where R is the rate
Pre-modern society
Poor living conditions keep death rates high, thus birth rates are correspondingly high
Thomas Malthus
Human populations increase exponentially and eventually outstrip food supply and collapse
Carl Marx
Population growth is an outcome of poverty and other social inequalities. Exploitation and Oppression the real problems
Technological optimists
Malthus was wrong, failed to account for scientific progress. Technology will solve all our problems
Simon
People are the ultimate resource.
Growth rate will lead to technological solutions to our resource problems
Elrich
We need to implement legislation to limit population growth
System
a network of relationships among a group of parts, elements, or components that interact with and influence one another through the exchange or energy, matter, and/or information
Eutrophication
excess nutrients in the water which increase, which increase the production of organic matter, which depletes the oxygen
Elements
substances that cannot be broken down into simpler form by ordinary chemical reactions
Electrons
revolve around the nucleus and bind one element to anotherDetermine the amount of protonsExtra electrons create electricity
Ions
Atoms electrically charged, due to gain or loss of electrons
Isotope
are alternate versions of elements which differ in mass by having a different number of neutrons. Stable or radioactive
Covalent
sharing of electrons- the more stable. Accumulate in fats
Ionic
cations and anions- selfish relationship, less stable * Salt is ionic and water is ionic. Like dissolves like
Lithosphere
Rock, sediment, soil below the earth’s surface
Macronutrient
elements and compounds required in relatively large amounts: nitrogen, carbon, phosphorous
Micronutrients
Nutrients needed in small amounts
Biogeochemical cycles
the movement (or cycling) of matter and energy through a system
Residence time
the average amount of time something spends in a reservoir
Residence time
the average amount of time something spends in a reservoir.
Long residence time
CO2 cycle
So only about half of our anthropogenic CO2 stays in the atmosphere. It goes into plants, the ocean, and rocks
Phosphorous cycle
Comes from rocks. Weathering releases. Water soluble. One of the 2 most important nutrients for plants to have. Phosphorous has no stable gas phase, so addition of P to land is slow (low P in rain), and P is not well distributed.
It can be transferred from the ocean to plants very effectively
Nitrogen cycle
Bacteria takes N2 out of the atmosphere and converts it into nitrates. Almost all is in the atmosphere.Today we are fixing as much nitrogen artificially as all bacteria do naturally. N20 a key greenhouse gas
Transpiration
The process where water goes from liquid to vapor through plants
Hydrologic cycle
Without more evaporation or transpiration, it cannot rain or snow- desertification (It’s a desert because there’s no plants there- plants keep the air with moisture). Warmer areas rain more. Rivers flow because there is more precipitation than evaporation
The rock cycle
The slow cycle of plate tectonics is what removes carbon from the atmosphere. Helps us find resources and tells us what we’re not likely to find
Species
All organisms of the same kind that are genetically similar enough to breed in nature and produce live, fertile offspring
