Please enable JavaScript.
Coggle requires JavaScript to display documents.
Ch. 25 Populations & Ecosystems (Structure of Ecosystems (Species…
Ch. 25 Populations & Ecosystems
Plants in Relationship to their Habitats
Abiotic components
nonliving/physical phenomena
climate and soil
climate
critically important to all organisms
most are restricted to certain regions
temperature, rainfall, humidity, winds
temperature
bromeliads, aroids, orchids
restricted to the tropics
frost-free habitats
tolerance range
between high & low extremes
ranges vary greatly from species to species
some are extremely broad
horizons
A horizon
uppermost
zone of leaching
litter and debris
B horizon
nutrients are washed ino this layer
zone of deposition
rich in nutrients
contains humus and clay
C horizon
composed of parent rock and rock fragments
soil factors
formed by breakdown of rock
pioneers
first plants that invade
no neighbors
provide transpired humidity
helps moderate wind
temper the environment
tolerate severe conditions
soil is sandy
little water holding capacity
associated w/ nitrogen-fixing prokaryotes
lichens contain cyanobacteria
angiosperms have root nod
Latitude and Altitude
latitudes contributes to abiotic environment
equator: 12 hr long days
no seasonal variation
plants cannot measure season
higher latitudes N/S
summer days are longer
longer winter nights
Artic & Atlantic Circles
mid-summer days are 24 hr
mid-winter are 24 hr
high altitudes on mountain tops
high winds
poor soil
all the year is cold
growing season is short
intense UV light
not fully shielded by ozone
oxygen
carbon dioxide
water vapor
disturbances
fires, landslides, snow avalanches and floods
significant radical change
affect the biotic factors directly
eliminating all/many individuals
altering soil
little/no impact on abiotic factors
climate
latitude
altitude
Biotic components
living factors
plant itself
modifies the habitat
beneficial
detrimental
neutral
beech/oak forests
produces a dense canopy
heavily shaded forest floor
few seedlings grow
creates habitats aids successful reproduction
pine forests
more open but still shaded
pine seedlings need full sunlight
do not grow well below canopy of older pines
modify habitat for continued success
other plant species
mutualism
beneficial for both organisms
competition
disadvantageous to both organisms
2 populations do not grow well together
limited supply of resources
habitat
#
migratory animals
winter area
summer area
migrations routes
migratory plant parts
spores
pollen
fruits
seeds
vegetative propagules
operational habitat
aspects of habitat that affect plants
all components are its habitat
Structure of Populations
Geographic Distribution
limiting factor
determines health of plants
random distribution
no obvious, identifiable pattern
no predictive value
knowing one position does not let you predict another
clumped distributions
spacing between plants is small/large
rarely average
can result from many factors
uniform distributions
occurs in orchards/tree plantations
evenly spaced
not extremely common
photosynthesis
medium level carbon dioxide
increase amount level of light
light is the limiting factor
light intensity increases
brighter light doesn't cause more rapid photosynthesis
increase level of carbon dioxide
carbon dioxide becomes limiting factor
any factor of ecosystem can be limiting
water
extreme temperature
allelochemics
plant of chemicals
allelopathy
inhibition
Age distribution: Demography
population responds to various factors
young, middle-aged, old individuals
optimal conditions
seeds do not germinate
many seedlings die
before able to reproduce
biotic potential
intrinsic rate of natural increase
number of offspring produced
reproduce under ideal conditions
carrying capacity
limited individuals in population
symbolized by K
https://www.britannica.com/science/carrying-capacity
R & K selection
r-Selection
disturbance usually produces
selected species
annuals/small shrubby perennials
K-Selection
K-selected species
face intense competition
adaptations increase ability use scarce resources
low light or soil strata in poor condition
Structure of Ecosystems
Physiognomic Structure
physical size and shape of organism
distribution in relation to others
life forms
trees, shrubs, herbs
defined by C. Raunkiaer
which plants survives stressful seasons
geophytes: bulbs, rhizomes
phanerophytes: trees, vine
Temporal Structure
changes an ecosystem undergoes w/ time
time span
animals active at night (nocturnal)
active during day (diurnal)
plants have daily rhythms opening/closing
change dramatically w/ season
Spring
renewed activity
production of flowers
new leaves
Summer
flower at distinct times (photoperiod)
controlled by plant maturity
adequate rainfall
nothing is in bloom
Autumn
changes depend on ecosystem
release seeds
Species Composition
number and diversity of species
coexist in an ecosystem
the climate stressful/mild
soil is rich/poor
tolerance ranges broad/narrow
stressful climate w/ poor soil
low number of species
few are adapted
mild climates w/ rich soil
support abundance of species
most plants have tolerance range
include such climatic and soil conditions
https://www.sciencedirect.com/topics/biochemistry-genetics-and-molecular-biology/species-composition
Trophic Levels
feeding levels
primary producers
autotrophs
first step of food web
energy and nutrient supply
herbivores
carnivores
secondary consumers
primary consumers
secondary producers
decomposers
break down remains
bacteria
fungi
Concepts
Ecology
the study of organisms in their surroundings
analyze structure, metabolism, diversity
population
individuals of the same species
do not strongly interact
community
all populations together
physical, nonliving environment
ecosystem
additional levels of interaction
uncertain of the effects
rarely stable
change more common
https://www.esa.org/about/what-does-ecology-have-to-do-with-me/
habitat components
