Organism require certain
elements to build their bodies
and metabolic process
Phosphorus
-Plants: take up phosphates
dissolved in soil water.
-Aquatic producers: in water
-Animals: by eating producers
or any other animal
-Component of ATP
-Phospholipids
-Nucleic acids
Ecosystem: Array of organisms and
abiotic things, interacting through
a one flow energy and cycling of
nutrients
Primary producers
(autotrophos) Energy from
nonliving things
Consumers (heterotrophos) By
feeding on tissues wastes and
remains of producers.
Consumers: -Herbivores:
plants -Carnivores: meet.
- Parasites: living host
-Omnivores:plants and
animals -Destritivores:
small particles of organic
material -Descomposers:
organic wastes(bacteria
and fungi)
THE NATURE OF
ECOSYSTEMS
Trophic Estrucutre of
Ecosystems
Trophic levels: hierarchy of
feeding relationship position in
Food Chain
Food Chain:sequence of steps of
energy
1st level: Primary
producers: obtain energy from a nonlivingsource.-sunlight-
2nd level: Primary consumers: Get
energyand carbonby feeding on
tissues and wastes
3rd level: Second
consumers: feeding on insects and tissues
4th level: Third
consumers: feeding on other animals
THE NATURE OF FOOD WEBS
Food Web: food chains of an
ecosystem cross-connect
Two division:
Graning food web
Primary Producers eating by
Primary Consumers
Detretial food web
Energy producers hows to
detritivores
Number of tranfers are
limited.
Energy captured by producers
passes through no more than 4 or
5 trophic levels
-Shortest:
conditions
vary widely
-Longer:
weathers has
no effect
-Complex:
large variety
of herbivores.
-Fewer: more
carnivores
ENERGY FLOW
System's gross primary
production: energy captured
by producers
Net primary production:
portion used for growth and
reproduction
Ecological pyramids:
trophic structure
Biomass pyramids: dry weight
of all organisms
Energy pyramid: how amount
of energy diminishes as it is
transferred through an
ecosystem
Ecological
Efficiency
Factors that influence the efficiency of tranfers
E.E is higher in aquatic ecosystems
Some components of a body
may be unavailable to a
consumer
Some is lost as
metabolic heat
BIOGEOCHEMICAL CYCLES
An element essential to life moves
between a community and its
enviroment through the living
component.
THE WATER CYCLE
Moves water from the ocean to the atmosphere, onto
land, and back to the ocean
-Liquid
-Evaporation
-Condenses
-Precipitation
Watershed: area in whict
all precipitation drains
into a specific waterway.
Soil water: some water
remains between soil
particles
Aquifers: water that drains
through soil layers often
collect
Groundwater: soil water
and soil aquifers
Runoff: water that flows over
soil into streams
Movement of water
Movement of:
-carbon
-nitrogen
-phosphorus
Limited
fresh water
Majority of Earth's
water is too salty to
drink or irrigales
crops
THE CARBON CYCLE
Atmospheric cycle:
biogeochemical cycle
in which a gaseous
form of an element
plays a significant
role
Terrestial Carbon cycle
Land plants take up CO2 to carry out photosynthesis
Soil Carbin consist of
humus and
organisms
Bacteria and fungi
decompose humus and
release carbon dioxide
Marine Carbon Cycle
Bicarbonate HCO3
Organisms
release
CO2
by
aerobic
respiration
Carbon Fossil Fuels
PHOSPHORUS CYCLE
Movement of
phosphorus among
Earth's rocks and
waters
Limiting factor
on plant growth
It's a component of all
nucleic acids and
phospholipids
NITROGEN CYCLE
Most organisms
cannot use this
gaseous form
DNA
RNA
Proteins
Nitrogen fixation:
incorporation of nitrogen
from nitrogen gas into
ammonia
Bacteria break the bonds in N2.
Form ammonia, then dissolves to
form ammonium NH4
Plants take ammonium
from soil water
Consumer obtain
nitrogen by eating
them
Bacteria and fungal
descomposer return
ammonium to the soil
by a ammonification
Ammonification: breakdown of
nitrogen-containing organic material
resulting in the release of ammonia
and ammonium ions
Nitrification: converts ammonium to nitrates
Denitrification: ecosystems lose nitrogen
Disruption of the Nitrogen Cycle
Burning fossil fuels and use of
industrially produced trinitrogen
fertilizers have altered the nitrogen
cycle
Nitrous Oxide
N2O can remain in the
atmosphere for more than
100 years
Nitrate Pollution NO3
Water pollutant
Ingest nitrate has negative effects.
-Cancer -Respiratory infections. -Diabetes
GREEN HOUSE GASES AND
CLIMATE CHANGE
Green house effect: ability to absorb and
reradiate heat energy. Helps to keep Earth
warm enough
Changing Carbon Dioxide
Concentrations
CO2 annual level in increasing
Analysis of ices cores has provided a
history that extends back 800,00 years
Also fossil foraminiferan
shells helped in the
research
Global climate change
A long-term of Earth's
climate. Example global
warming
Intergovermental Panel on Climate concluded
that is very likelly that a human-induced
increase in atmospheric greenhouse gases is
responsible for the current warming trend