environmental science part II
| created: | about 1 month ago by hmtucker123 | tags: | environmental science |
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Growth rate |
the rate of a growth of a population, as a percentage. |
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total fertility rate |
the average number of children each woman has over her lifetime |
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replacement-level fertility |
a fertility rate that wil just replace a woman and her partner. theoretically 2.0, but adjusted slightly higher because of mortality and failure to reproduce. |
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infant mortaility |
infants deaths per thousand live births |
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population profile |
a bar graph plotting numbers of males and females for successive ages in population, starting with the youngest at the bottom |
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population momentum |
the effect of current age structure on future population growth. ie: you poopulations will continue growing even after replacement-level fertility has been reached, ue to reproduction by already existing age groups |
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crude birthrate |
the number of live births per thousand in a popluation in a given year |
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crude deathrate |
the number of deaths per thousand in a population in a given year. |
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doubling time |
the time it takes for a population to increase a t a given growth rate and double in size |
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epidemiologic transition |
the shift from high death rates to low death rates in a population as a result from medical and sanitary developments |
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fertility transition |
the decline of birthrates from high levels to low levels in a population |
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demographic transition |
the tendacy of a popuation to shift from high birth and death rates to low birth and death rates as a result of the epidemiologic and fertility transitions |
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what are the thre main ecnomic categories (according to the UN)? |
1. high income, highly devoloped, indutrialized countries 2.middle-income, moderately developed countries 3.low-income developing countries |
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envrionmental impact farmula is? |
I = P*A*T |
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the IPAT formula can be modified and reduced by what? |
I= P*A*T / S |
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demography |
field of collecting, compiling, and presenting info about a population |
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what was the ICPD? |
the international conferance on population and development in cairo in 1994 |
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dependacy ratio |
the ratio of the nonworking population to the working population |
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remittances |
money immigrants send home |
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what is the grameen bank? |
a bank the provides micolending ; developed by muhhamad yunas in 1976, bangledash |
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sand |
particles from 2.0 to .02mm in size |
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silt |
particles range from .02 down to .002 mm |
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clay |
anything finer than .002 mm |
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soil texture |
relative proportions of each kind of particle |
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loam |
40% sand, 40% silt, 20% clay |
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workability |
the ease with which soil can be cultivated |
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name the horizons in order from top to bottom of a soil profile |
O horizon (surface, decomposing matter) |
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eluviation |
process of leaching |
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soil fertility |
the soils ability to support plant life |
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leaching |
process where water nutirents are washed through the soil by water |
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transpiration |
when water is passed through the roots, absorbed and released in the air as water vapor |
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soil aeration |
diffusion of oxygen into and carbon dioxide out of the soil |
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a solution that is neither acidic nor akialine has a PH of what? |
7 |
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splash erosion |
raindrop break-up the cumpy structures of top soil |
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substinence farmers |
farmers who live on small parcels of land that provide them with food for their households, and it is hoped, a small cash crop |
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food security |
assured access for every person to enough nutritious food to sustain an active and healthy life |
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pests |
any organism that is noxious, destructive or troublesome |
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herbicides |
chemicals that kill plants |
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pesticides |
chemicals that kill animals and insects |
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chemical treatment |
the use of "antibiotic" method to kill pests |
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ecological control |
stimulate immune system to fight of pests |
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integrated pest management IPM |
an attempt in controling pest populations by using all suitable methods, chemical and ecological, that brings about long-term pest management of pest population and has minimal environmental impact |
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scale insects |
insect that suck the juices from plant cells |
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problems stemming from chemical pesticide use |
1. devlopment of resistence by pests 2. resurgences and secondary-pest outbreaks 3. adverse environmental and human health effects |
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resurgence |
after a pest has been virtually eliminated with pesticide, a pest populations not only recovers, but explodes to higher and more severe levels |
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pesticide treadmill |
term coined by Robert van den bosch to describe attempts to eradicate the pests |
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biomagnification |
multiplying affect of biaccumulation that occures through the food chain |
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hormones |
chemicals produced in humans and other animals to provide "signals" that control development processes and metabolic functions |
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pheromones |
chemecals secreted by one individual the influences the behavior of another individual of the same species |
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juvenille hormone |
triggers caterpiller pupation by decreas levels |
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economic threshold |
when the costs of pesticide outway the benfit |
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cosmetic spraying |
pesticide the only protects the appearance of produce from pests |
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delaney clause |
no food additive is to be deemed safe if it is found to enduce cancer when injested by human or other animal |
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tolerances |
limit the amount of pesticides on or in foods |