AN ECOLOGICAL SYSTEM: THE BIOGEOCHEMICAL CYCLES

The water cycle The Carbon Cycle The Nitrogen Cycle The Phosphorus CycleThe cycling of nutrients through the

biosphere for use throughout the system by food chains, webs, and the biosphere.

The nutrients: carbon, hydrogen, oxygen, Nitrogen, and Phosphorus

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BIOSPHERE:5 MILES UP AND 5 MILES DOWN

THE WATER CYCLE: HYDROGEN AND OXYGEN

Continuously moves throughout the atmosphere, the land, and waters (oceans, lakes and rivers)

Water vapor condenses in the air and falls as precipitation then gets back into the air during evaporation

Evaporation from plants is called Transpiration

transpiration

The Water Cycle

THE CARBON AND OXYGEN CYCLES: CARBON AND OXYGEN

The continuous movement of carbon and oxygen from non-living into living organisms

CO2 in atmosphere build organic molecules

Plants use CO2 to produce O2 This exchange of CO2 for O2 is called

Respiration (cellular respiration) Combustion or burning releases carbon Burning trees, fossil fuels: oil and coal

The Carbon Cycle

NITROGEN CYCLE: NITROGEN (N)

Nitrogen Is needed to make proteins (DNA, RNA, Enzymes)

Is a process where nitrogen circulates among the air, soil, water, and organisms

Nitrogen Fixation: where bacteria that live in soil or on roots, or lightening change chemical composition of N2 into ammonia – a useable form of nitrogen by living organisms

NITROGEN CYCLE:

Nitrification: The changing of un-useable nitrogen, nitrite, into useable Nitrate

De-nitrification: Changes nitrate into nitrogen gas that returns to atmosphere

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BIOLOGICAL NITROGEN FIXERS

Cyanobacteria – blue-green algae Free living soil bacteria Mycorrhizae:

Symbiotic bacteria living in root nodules

Chemical Fixators: Lightening

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Root nodules on Cassia fasciculata

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The Nitrogen Cycle

PHOSPHORUS CYCLE: PHOSPHORUS

An important ingredient in DNA and RNA and all proteins

Flows in organism in different chemical forms into the surroundings and back into organisms

Doesn’t enter atmosphere In soil and rock. Dissolves and is used

by plants Plants are eaten by animals, animals

die, cycle begins again

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Phosphorous Cycle

Phosphate – PO4-3

The Phosphorus Cycle

CYCLES COMPARED TO ENERGY FLOW Cycles are recycled through the

biospere by food webs, the hydrosphere, the biosphere, the geosphere, atmosphere

Energy flows through food webs, is made by plants initially from the sun

Is used by living organisms, passed on, and is lost into space

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DO YOU SEE THE ENERGY FLOW AND CYCLES?

ECOLOGICAL SUCCESSION

❊ The orderly, natural changes and species replacements that take place in the communities of an ecosystem.

❊ Over time biotic and abiotic factors create ecological conditions that are suitable for some organisms and unsuitable for others.

❊ Changing the ecosystem along the way.

PRIMARY SUCCESSIONSuccession beginning in an area or surface on which

there has never been life before

Exposed rock

Lichen & mosses

Grasses, herbs, scrubs,

larger scrubs, tree seedlings

Aspen, jackSpruce, pines

White spruce, Balsam fur,Paper birch

TIME

SECONDARY SUCCESSIONOccurs in a region in which life has existed

before, but the previous community structure has been disrupted

Frequently seen in North Georgia where cultivated fields like old cotton or soybean fields are abandoned

Secondary SuccessionWhat could cause the previous ecological

community to have been disrupted?

FLOODLANDSLIDE

FIRE

CLIMAX COMMUNITY

BIOMES A large region characterized by a specific type of climate and certain types of plants and animals