Ecology One. Biosphere Biome Ecosystem Population Community Organism.
Chapter 3 Ecology, ecosystems and food webs Ecology Groupings Organism – single living thing...
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Transcript of Chapter 3 Ecology, ecosystems and food webs Ecology Groupings Organism – single living thing...
Chapter 3
Ecology, ecosystems and food webs
Ecology
Groupings Organism – single living thing Species – several of same type of organism Population – several of same species
interacting Community – several populations interacting in
a certain area Ecosystem – community interacting with each
other and the environment
Fig. 4.2, p. 72
BiosphereBiosphere
Ecosystems
Communities
Populations
Organisms
Parts of the planet
Planet as a solid – inner/outer core, mantle, crust
Lithosphere is the crust and asthenosphere Hydrosphere is the water regions Atmosphere is the 5 layers of air
– Troposphere (11 miles) 78% N2, 21% O2, 1% Ar
– Stratosphere (11 – 30 mi) O3, blocks UV
Fig. 4.6, p. 74
Atmosphere
Vegetation and animals
Soil
Rock
Biosphere
Crust
core
MantleLithosphere
Crust
Lithosphere(crust, top of upper mantle)
Hydrosphere(water)
Atmosphere(air)
Biosphere(Living and dead
organisms)
Crust(soil and rock)
Incoming solar energy
34% reflected by clouds 42% heats earth and atmosphere 23% evaporates water 1% creates wind <1% photosynthesis
Fig. 4.8, p. 75
Solarradiation
Energy in = Energy out
Reflected byatmosphere (34%)
UV radiation
Absorbedby ozone
Absorbedby the earth
Visiblelight
Lower Stratosphere(ozone layer)
Troposphere
Heat
Greenhouseeffect
Radiated byatmosphere
as heat (66%)
Earth
Heat radiatedby the earth
Greenhouse effect
Solar energy (light) that reaches the earth is converted into short wave radiation (heat) infrared.
This infrared radiation has a hard time passing through the gasses in our atmosphere thereby trapping heat and keep the planet about 30 degrees (Celsius) warmer
Important gasses – H2O, CO2, CH4, N2O, O3
Biomes
Large regions characterized by a distinct climate and adapted vegetation
Remember climate is weather patterns over a long period of time, usually several decades
Because certain plants are adapted to a particular biome, so too are certain animals which depend on those plants for food
Biomes
There are not distinct boundaries between biomes, rather there are ecotones.
An ecotone is a blending of biomes and generally carries a greater quantity and variety of species
Components of Ecosystems
Abiotic – nonliving– Sunlight– Temperature– Precipitation– Wind– Latitude– Soil – Salinity (aquatic)
Fig. 4.13, p. 79
Terrestrial Ecosystems Aquatic Life Zones
• Sunlight
• Temperature
• Precipitation
• Wind
• Latitude (distance from equator)
• Altitude (distance above sea level)
• Fire frequency
• Soil
• Light penetration
• Water currents
• Dissolved nutrient concentrations (especially N and P)
• Suspended solids
Components of Ecosystems
Range of tolerance – how much of an abiotic factor can an organism withstand
Limiting factor – the one factor that is holding back a population from reaching its biotic potential (max growth)
Important limiting factors in aquatic systems– Dissolved oxygen, salinity, temperature, light,
nutrients, etc.
Fig. 4.14, p. 79
Po
pu
lati
on
siz
e
Low High Temperature
Zone ofintolerance
Zone ofphysiological stress
Optimum range Zone ofphysiological stress
Zone ofintolerance
Noorganisms
Feworganisms
Lower limitof tolerance
Abundance of organismsFew
organismsNo
organisms
Upper limitof tolerance
Food webs (chains)
Producers (autotrophs) plants– Using chemosynthesis (some bacteria)– Using photosynthesis (plants)
6 CO2 + 6 H2O + sun (yields) C6H12O6 + 6 O2
Plants convert only about 1-5% of the light they absorb into chemical energy, and absorb only about half the light that strikes them
Herbivores
Primary consumers – eat producers (oh the humanity)– Teeth designed for grinding
Carnivores
Secondary consumers – meat eaters only Feed on primary consumers (herbivores)
Teeth designed for tearing (large canines and sharp molars) cats for example
Omnivore
Tertiary consumer – eat anything, feeding on other carnivores makes them tertiary
We are omnivores, just look at our teeth, – but we really should eat more veggies and less
meat (in my opinion)
The other consumers
Scavengers – feed on dead organism they did not kill, but found dead
Detritivores – feed on parts of dead organisms
Decomposers – bacteria and fungi, break down small detritus into raw nutrients
Biodegradable means can be broken down by decomposers
Aerobic respiration
Normal cellular process for most organisms
Convert sugar and oxygen into energy leaving water and carbon dioxide as products
C6H12O6 + 6O2 yields 6 CO2 + 6 H2O + energy
Anaerobic Respiration
Also called fermentation The breakdown of glucose without oxygen
present
Produces: methane, ethyl alcohol, acetic acid, and hydrogen sulfide
Food chains
Trophic level – feeding level First trophic level – plants Second trophic level – primary consumers Third trophic level – secondary consumers Fourth trophic level – tertiary consumers
Remember heat is lost in every transfer between trophic levels
Pyramid of energy flow
Only about 10% of the usable energy transfers between trophic levels (5-20%)
For this reason we must rely on the transfer of solar energy from producers to consumers
This is why it is so important to care for the plants of this planet
Biomass
Organic matter produced by producers (photosynthesis)
Total dry weight of organic matter in plants and animals in an ecosystem
Biomass Productivity
Highest net biomass productivity per square meter is in wetlands, estuaries, and rain forests
Highest gross (but lowest per sq. meter) is the open ocean. Because of its size it has a lot of algae that add up to high productivity
Nutrient cycles
Atmospheric – Carbon and Nitrogen Sedimentary – Phosphorus and Sulfur
Hydrologic cycle – water cycle helps to transport many nutrients
Hydrologic cycle
Evaporation/transpiration Condensation Precipitation Infiltration Percolation Runoff
Powered by the Sun and gravity
Carbon cycle
Atmosphere
Photosynthesis/respiration
Fossil fuels Limestone Dissolved in the ocean
Nitrogen cycle (very important)
Nitrogen in the air Nitrogen fixation by bacteria to ammonia Nitrification by bacteria to nitrite NO2
-
Nitrification by bacteria to nitrate NO3- Assimilation by plants Ammonification of dead organic material by
bacteria and fungi Denitrification of nitrate by bacteria back to
atmosphere
Phosphorus cycle
Very slow Limited amount found in the soil Limiting factor for plant growth Excess causes prolific plant growth (algal
blooms in water)
We add phosphates to detergents/fertilizers
Sulfur cycle
Passed as sulfates (salts) mostly Hydrogen sulfide (swamps/volcanoes) Sulfur dioxide (volcanoes) Ammonium sulfate (sea spray)
Reacts in atmosphere to create hydrogen sulfate (H2SO4) sulfuric acid (acid rain)
Ecosystem services
Waste removal pest control Soil formation biodiversity Water purification matter resources Air purification aesthetic pleasure Climate control Recycling vital chemicals Renewable energy
Achieve sustainability
Use renewable energy (especially solar)
Recycle chemical matter
REALIZE WE LIVE IN A CLOSED SYSTEM!
The END!!!