Term
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Definition
| how the number of individuals increases or decreases with time controlled by the rate at which new individuals are added to the population through the porcesses of burth and immigration and the rate at which individuals leace the population through the porcesses of death and emigration |
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Term
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Definition
| populations in which immigration and/or emigration occur |
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Term
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Definition
| polutaions in which movement into and out of the population does not occur (or is not a significant influence on population growth) |
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Term
Population size= N(t)
t= time
d= death
b= birth
Number of Births= B(t) = bN(t)delta(t)
Number of Deaths = D(t) = dN(t)delta(t)
Population Size for next time period= N(t + delta(t))= N(t) + B(t) - D(t)
r= (b-d)
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Definition
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Term
| Exponential Population Growth Equation |
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Definition
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Term
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Definition
| no change in population size |
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Term
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Definition
| population increases exponentially |
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Term
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Definition
| exponential decline in the population |
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Term
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Definition
| characteristic of populations inhabiting favorable environments at low population densities |
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Term
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Definition
| an age-specific account of mortality |
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Term
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Definition
| a group of individuals born in the same period of time |
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Term
x= age in years
nx= the number of individuals from the original cohort still alive at x
lx= probability of surviving to any given age
dx=difference between nx and nx+1
qx= dx/nx |
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Definition
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Term
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Definition
1. cohort/dynamic
2. time-specific |
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Term
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Definition
| the fate of a group of individuals is followed from birth to death |
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Term
| Dynamic Static Composit Table |
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Definition
| modification of the dynamic life table that constructs a cohort from indiiduals born over several time periods instead of just one |
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Term
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Definition
| constructed by sampling the population in some manner to obtain a distribution of age classes during a single time period |
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Term
| Time-Specific Life Table Assumptions |
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Definition
1. each age class was sampled in proportion to its numbers in the population
2. age-specific mortality rates have been constant over time |
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Term
| Plant Demography Life Tables' Studies |
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Definition
1. seefling mortality and survival
2. population dynamics of perennial plants marked as seedlings
3. life cycles of annual plants |
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Term
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Definition
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Term
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Definition
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Term
| Survivorship Curves' Idealized Types |
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Definition
type I- survival rate is high throughout the life span followed by heavy mortality at the end, convex curve
type II- survival rates do not vary with age, straight curve
type III- mortality rates are extremely high in early life, concave curve |
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Term
| Standard Convention for Expressing Birthrates |
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Definition
| births per 1000 population per unit time |
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Term
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Definition
| number of young produced per unit area |
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Term
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Definition
| average number of offspring produced per individual per unit time as a function of age class |
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Term
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Definition
| sum of the mean number of females born to each female age group |
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Term
| Fecundity/Fertility Table |
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Definition
uses the survivorship column, lx, from the life table together with the age-specific birthrates, bx,
lxbx |
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Term
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Definition
| R0, the average number of females that will be left during a lifetime by a newborn female; provides a means of evaluating both the individual (fitness) and population consequences of specific life history characteristics |
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Term
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Definition
| the proportion of individuals alive at the beginning of an age class that die before reaching the next age class, sx, 1-qx |
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Term
| Population Projection Table |
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Definition
| chart of growth of population developed by calculating the births and mortality of each age group over time |
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Term
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Definition
| the proportion of individuals in each age group winthin a population; divide the number in each age class (x) by the total population size for that year N(t)x |
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Term
| Finite Multiplication Rate (Lambda) |
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Definition
| dividing total number of individuals in a year t+1, N(t+1), by the total number of individuals in the previous year N(t) |
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Term
| Concepts of Population Projection Tables |
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Definition
1. rate of population growth, as estimated by lambda, is a function of the age-specific rates of survival (sx) and birth (bx)
2. constant rate of increase of the population from year to year and the stable age distribution are results of survical and birth rates for each age class that are constant through time |
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Term
| Projection of Population Size |
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Definition
| given a stable age distribution, N(t+1)=N(t)(Lambda), N(t)=N(0)Lambda^t |
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Term
| Geometric Population Growth |
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Definition
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