Biogeochemical Cycles

chemistry :((

Carbon-Oxygen Cycle

The continuous exchange of carbon and oxygen from non-living environment and to the living.

Aerobic Cellular Respiration

Organisms break down glucose for energy. Oxygen is the input, carbon dioxide output.

Anaerobic Respiration

When oxygen is absent glucose breaks down with a catalyst releasing energy.

Ocean Acidification

When atmospheric carbon reacts with water, forming carbonic acid in the ocean.

How does carbonic acid affect the environment?

It can erode away skeletons and rocks in ecosystems.

Carbon Sinks

Store carbon for a period of time.

Examples of Carbon Sinks

Plants, animals, oceans.

Cellular Respiration

Organisms combine food molecules and oxygen, gives off carbon dioxide. Basically plant breathing.

Water Cycle

The continuous movement of water on and above the Earth’s surface powered by the sun.

Photosynthesis

Plants use the sun’s energy to convert water and carbon dioxide into oxygen and sugars.

Stages of the Water Cycle

Evaporation, condensation, precipitation, infiltration, transpiration, surface run-off.

Evaporation

Liquid to gas, molecules rise into the air in the form of water vapour.

Condensation

Gas to liquid, water cools and forms clouds.

Precipitation

When cloud is fully condensed, water falls in the form of rain, sleet, snow etc.

Infiltration

Water soaks into the ground collecting in layers of rock.

Transpiration

Groundwater is absorbed by plant roots when water evaporates from plants, photosynthesis.

Surface Run-off

Water that cannot soak into the ground, flows across land.

Human Impacts on the Water Cycle

• Deforestation: evaporation is disrupted, decreased precipitation, decreased respiration.
• Enhanced Greenhouse Effects: Earth’s temperature rises and therefore so does the evaporation rate.

Nitrogen Cycle

The process of how nitrogen changes forms as it is recycled through the biosphere.

Importance of Nitrogen in the Biosphere

It is crucial for forming proteins.

Forms of Oxygen and where they’re found.

Inorganic: Nitrogen gas in the atmosphere. Organic: Wastes & living and dead organisms.

Types of Proteins in the Nitrogen Cycle

Nitrogen fixing

Nitrifying

Denitrifying

Nitrogen Cycle: Nitrogen Fixation

Nitrogen fixing bacteria take up atmospheric nitrogen, converting it to ammonia.

Processes that Fix Nitrogen:

Nitrogen FixationLightning

Nitrogen Cycle: Nitrification

Nitrifying bacteria converts ammonia to nitrite and nitrate ions.

Nitrogen Cycle: Assimilation

Plants absorb ammonium, nitrate, and nitrites.

Nitrogen Cycle: Ammonification

Decomposers return nitrogen to soil by converting compounds in dead organisms to ammonia.

Nitrogen Cycle: Denitrification

Denitrifying bacteria converts nitrates and nitrites to nitrogen gas, releasing it into the atmosphere.

How do animals receive nitrogen?

By feeding on plants that have nitrogen in their roots, they get their nitrogen. Then the food chain continues this process.

Haber-Bosch Process

Synthetic fertilisers where atmospheric nitrogen reacts with hydrogen, turning it to ammonia.

Effects of Nitrogen Fertiliser

Excessive nutrients in water, leading to excessive bacterial growth.

Human Impacts on the Nitrogen Cycle

Burning fossil fuels, nitrogen fertilisers, agriculture.

Eutrophication

Water become excessively enriched with minerals and nutrients.

Algae Blooms

Algae colonies that grow out of control, producing toxic or harmful effects on living organisms.

Phosphorus Cycle

The process of transformation and locations of phosphorus through the hydrosphere, lithosphere and biosphere.

Importance of the Phosphorus in the Biosphere

Required for ATP energy, nucleic acids, cell membranes, and bones.

What is Biogeochemical Cycle does not enter the Atmosphere?

Phosphorus cycle.

Phosphorus Cycle: Weathering

Rocks release phosphate ions and minerals.

Phosphorus Cycle: Assimilation

Plants take inorganic phosphate from soil for use.

Phosphorus Cycle: Decomposition

Dead organisms wastes decompose and organic phosphate is returned to the soil.

Phosphorus Cycle: Mineralisation

Organic forms of phosphate are given to plants via bacteria. This bacteria breaks down organic matter into inorganic phosphate.

Phosphorus Cycle: Sedimentation

Phosphorus can form rocks and end up in sediments.

Human Impact on the Phosphorus Cycle

Mining for phosphorus, relocating it. Altering the distribution of phosphorus.