NUTRIENT CYCLES

ELEMENTS CARBON HYDROGEN NITROGEN OXYGEN PHOSPHORUS SULFUR 6 IMPORTANT ELEMENTS IN BIOLOGY: CARBON HYDROGEN NITROGEN OXYGEN PHOSPHORUS SULFUR

ENERGY FLOW Energy flows through the ecosystem—passed on from one organism to the next through food chains… ENERGY CANNOT BE RECYCLED!!!

MOVEMENT OF MATTER Matter also flows through ecosystems, however, it CAN BE recycled within and between ecosystems. Matter moves through ecosystems in BIOGEOCHEMICAL CYCLES.

BIOGEOCHEMICAL CYCLES Biogeochemical cycles connect: Biological aspects of the biosphere Geological aspects of the biosphere Chemical aspects of the biosphere

THE WATER CYCLE AKA: THE HYDROLOGIC CYCLE PRECIPITATION: The process in which water (in the form of rain, snow, sleet, or hail) falls from clouds in the sky.

THE WATER CYCLE AKA: THE HYDROLOGIC CYCLE EVAPORATION: Water changing from a liquid to a gas TRANSPIRATION: Evaporation of water from a plant’s leaves

THE WATER CYCLE AKA: THE HYDROLOGIC CYCLE CONDENSATION: The process in which water vapor (a gas) in the air turns into liquid water. Condensing water forms clouds in the sky. Water drops that form on the outside of a glass of icy water are condensed water.

THE WATER CYCLE AKA: THE HYDROLOGIC CYCLE ACCUMULUATION: Water pools in large bodies (oceans, seas and lakes). SEEPAGE: Water entering the ground RUN-OFF: Water leaves land and enters a body of water

NUTRIENTS Nutrients are all the chemical substances that an organism requires to live.

NUTRIENTS Nutrient cycles that play especially prominent roles in the biosphere: Carbon Cycle Nitrogen Cycle Phosphorus Cycle

THE CARBON CYCLE Carbon is especially important to living systems because it is the key ingredient in all living organisms.

PROCESSES IN THE CARBON CYCLE BIOLOGICAL PROCESSES: Photosynthesis Respiration Decomposition of plants and animals

PROCESSES IN THE CARBON CYCLE GEOCHEMICAL PROCESSES: Release of carbon dioxide to the atmosphere by volcanoes

PROCESSES IN THE CARBON CYCLE MIXED GEOCHEMICAL PROCESSES: Burial of carbon-rich remains of organisms and their conversion to fossil fuels

PROCESSES IN THE CARBON CYCLE HUMAN ACTIVITY: Mining Burning fossil fuels Cutting/burning forests

CARBON RESERVOIRS In the atmosphere as gas Dissolved in the oceans Underground as coal, petroleum and calcium carbonate rock

USING CARBON DIOXIDE Animals release carbon dioxide as a waste product in cellular respiration. Plants take in carbon dioxide to use for photosynthesis.

THE NITROGEN CYCLE Why do we need nitrogen? Nitrogen is necessary for organisms to make amino acids… …which are needed to build proteins!!!

In the atmosphere as gas 78% of the air is N2 gas NITROGEN RESERVOIRS In the atmosphere as gas 78% of the air is N2 gas

PROCESSES IN THE NITROGEN CYCLE NITROGEN FIXATION: The process by which bacteria convert nitrogen into ammonia (NH3) AMMONIFICATION: Decomposers return nitrogen gas (N2) to the soil as ammonia (NH3)

PROCESSES IN THE NITROGEN CYCLE NITRIFICATION: The process by which some soil bacteria convert ammonia (NH3) into nitrates (NO3)

PROCESSES IN THE NITROGEN CYCLE DENITRIFICATION: The process by which some soil bacteria convert nitrates (NO3) into nitrogen gas (N2) This process releases nitrogen into the atmosphere once again.

The story of my fish tank…

AMMONIA (NH3) is released through respiration & excretion Ammonia is very deadly in high concentrations—so enough fish producing ammonia in a small space (like an aquarium)…will kill the fish.

Well, this doesn’t have to happen… Bacteria present in an aquarium will feed on ammonia producing nitrites…another bacteria will feed on nitrites producing nitrates… Nitrates are not nearly as harmful, and much, much easier to control. You would need OBSCENE amounts for it to do any real damage.

Why do we need phosphorus? THE PHOSPHORUS CYCLE Why do we need phosphorus? Phosphorus is necessary for forming DNA and RNA

THE PHOSPHORUS CYCLE Phosphorus remains on land in rock/soil/ocean sediment Phosphate is released as rocks/sediments break down Plants absorb the phosphate from the soil or water

The primary productivity of an ecosystem is the rate at which organic matter is created by producers.

LIMITING NUTRIENTS A nutrient is “limited” when an ecosystem is in short supply of that nutrient… …this will limit an organism’s growth.

LIMITING NUTRIENTS Ocean and saltwater environments NITROGEN Streams, lakes and freshwater environments NITROGEN PHOSPHORUS

LIMITING NUTRIENTS A large input of a limiting nutrient (P or N) results in an immediate increase in the amount of algae and other producers. This is called an algal bloom.

ALGAL BLOOMS Algal blooms occur because there are more nutrients available—and therefore producers can grow and reproduce more quickly.

WHAT IS THE PROBLEM WITH ALGAL BLOOMS? The algae and other producers cover the water and this cuts off the sunlight to other plants and animals and decreases the amounts of oxygen.