BIOGEOCHEMICAL CYCLES

BIOGEOCHEMICAL CYCLES

Law of conservation-atoms atoms neither created or destroyed

Same atoms must be passed around again and again

CHNOPS make up 98% of living biomass

Biogeochemical cycles move atoms (matter, nutrients, CHNOPS) through the air, soil, water, rocks, and living organisms.

Recycling of atoms & flow of energy sustain life on earth

BASIC PROCESS

Producers incorporate atoms (inorganic form) from nonliving reservoirs and convert to organic molecules

Consumers eat producers

Decomposers break down organic molecules to return atoms (inorganic form) back to abiotic

What to look for in a cycle?

Why is nutrient important?

What are the reservoirs for the nutrient involved?

What are the driving forces that transfers nutrient from abiotic to biotic and back to abiotic

How have humans upset the natural cycling of particular nutrient?

Description of cycle

WATER CYCLE-Why important

Living things are 75% water

Hydrogen in water supplies protons and electrons for photosynthesis

Oxygen in water is released as free oxygen into air during photosynthesis

Major solvent in living things for chemical reaction to take place in cells and transport

Homeostasis-high specific heat

Water Cycle-Reservoirs

Ocean

Atmosphere

Glaciers

Fresh water

Ground water

Living things

Water cycle-Driving force

The sun is the major driving force of the water cycle

Causes evaporation

Causes transpiration

When cooler causes precipitation

Water cycle-Human Effect

Withdraw large amounts of water

Pollute water

Deforestation (climate change)-Loss of transpiration-less water in atmosphere & increases temperature dries out soil. Creates desert. More carbon dioxide increases global warming.

Description of water cycle

Sun heats water in ocean

Evaporates as vapor into air

Transpiration from trees also add water vapor to atmosphere

Cooler temperatures cause vapor to condense and precipitate

Water returns directly to oceans as precipitation or indirectly by runoff

Building blocks of cells-Proteins, Lipids, Carbohydrates, Nucleic acids are carbon based molecules

Carbon and oxygen from carbon dioxide is used to make glucose in photosynthesis

Carbon Cycle-Why important?

Carbon cycle reservoirs

Atmosphere in the form of inorganic carbon dioxide

Carbon dioxide dissolved in oceans

Living things in form of organic molecules

Underground-fossil fuels

Rocks-limestone (calcium carbonate)

Carbon cycle driving force

Photosynthesis captures inorganic carbon in form of carbon dioxide and converts it to organic molecules (glucose)

Cell respiration returns carbon dioxide to abiotic

Carbon cycle-Human effect

Humans are adding excess carbon dioxide to atmosphere through burning of fossil fuels and deforestation (loss of carbon dioxide removal)

Carbon cycle description

Carbon dioxide is captured by plants and converted into organic molecules by photosynthesis

Consumers eat plant and carbon ids transferred

Organism die and decomposers break organic molecules back to carbon dioxide and released back to air

Cell respiration also returns carbon dioxide back to air.

Burning fossil fuels & volcanoes increase carbon dioxide in air

Nitrogen Cycle-Why important

Important in making nucleic acids, ATP, and Amino acids

Nitrogen Cycle-Reservoir

Atmosphere is 75% free nitrogen

Nitrogen Cycle driving force

Bacteria

Nitrogen fixing bacteria capture free nitrogen from air and convert it to ammonia

Nitrifying bacteria-convert ammonium to nitrates and nitrites

Denitrifying bacteria convert nitritrites back to free nitrogen

Ammonifying bacteria convert organic molecules to ammonium

Nitrogen Cycle-human effect

Fertilizers contain large amounts of nitrogen-run off in stream create eutrophication

Nitrogen released into air by factories combine with water to form nitric acid-acid rain

Farming depletes soil of nitrogen

Nitrogen cycle description

Free atmospheric nitrogen is converted by nitrogen fixing bacteria found in soil and root nodules of legumes to ammonia

Plants can use ammonia but ammonia is usually converted to nitrates and nitrites by nitrifying bacteria which plants take up

Consumers eat plants

Organisms die and ammonifying bacteria convert back to ammonia which can be nitrified and reused or denitrified by denitrifying bacteria to free nitrogen again.

Create your own slides for the phosphorus cycle