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Population and Ecosystems - Coggle Diagram
Population and Ecosystems
The structure of population
Age distribution: Demography
manner in which a population responds to various factors
Two factors affect the possible rate
Generation time
the length of time from the birth of one individual until the birth of its first offspring
affects the rapidity of population growth
intrinsic rate of natural increase
number of offspring produced by an individual that actually live long enough toreproduce under ideal conditions
r- and K- selection
r-selection
immigrants cartried by winds, animals or survivors
reproduces quickly and population growth
produced by disturbance
k-selection
phenotypes are very different from beneficial
condition in a crowded habitat
population close to its carrying capacity
Geographic Distribution
Boundaries of the geographic range
limiting factor
one factor alone determines the health of the plant
Soil factors
produce the abrupt boundaries for the geographic ranges of populations
ability of a plant species
spread throughout a geographic area
Biotic factors
Local geographic distribution
clumped
spacing between plants is either small or large
result from many factors
uniform
not extremely common
result from intraspecies competition
occur in and tree plantations
random
no obvious to the positions of individuals
no predictive value
Plants in relationship to their habitats
Abiotic components of the habitat
Soil factors
decay contributes humus
increasing the soils water-holding capacity
dead plants
substrates for soil organisms
little water-holding capacity
A horizon
uppermost
consists of litter and debris
washes nutrients from it downward
zone of leaching
pioneers plants
lichens contain cyanobacteria
some angiosperms have root nodules
nitrogen-fixing prokaryotes
B horizon
materials from A horizon accumulate
contains both humus and clay
zone of deposition
formed by breakdown of rock
C horizon
mostly of parent rock
rock fragments
Latitude and Altitude
At the equator
Days are 12 hours long
plants cannot measure season by photoperiod
no seasonal variation occurs
Arctic and Antarctic Circles
mid-summer days are 24 hours long
At higher altitudes
temperature fluctuate greatly
the sun is rarely overhead
soil formation is slow
high altitudes
growing season is short
the year is cold
high winds and poor soil
not fully shielded by ozone, oxygen, carbon dioxide, and water vapor
Climate
critically important to all organisms
lower winter temperature
temperature, rainfall, relative, humidity, and winds
highest summer temperature
killing frost in the spring
first killing frost of autumn
Disturbance
fires, landslides, snow avalanches, and floods
alters species relationships
affect the biotic factors directly
radical change in an ecosystem
Biotic components of the habitat
Other plant species
mutualism
beneficial interaction for both organisms
competition
use the same limited supply
competitive exclusion
excluded from the ecosystem by superior competitors
two populations do not grow as well together
Organisms other than plants
Commensal relationships
one species benefits
other is unaffected
Predation
one species benefits
other is harmed
The plant itself
trees modify the habitat
producing a dense canopy
heavily shaded forest floor
habitat modification
detrimental
neutral
beneficial
The structure of ecosystems
Tropic levels
chemosynthetic bacteria bring chemical energy
feeding levels
autotrophs brings energy to ecosystem
contains some members, autotrophs
brings energy to the system
Species composition
coexist in ecosystem
stressful climate support and abundance of species
depends on climate
mild and rich climate supports and abundance of species
Temporal structure
spring-time of renewed activity
changes that an ecosystem undergoes with time constitute
time span can be short
plants change dramatically with the season
Physiognomic structure
physical size and shape of the organism
air distribution in relation to each other and to the physical environment
combinations of life forms, vertical structures and characteristics