Element Cycles Energy Flow & Cycles Element Cycles (Revised August 4, 2003)

BIOGEOCHEMICAL CYCLES Matter within ecosystems is recycled. BIOGEOCHEMICAL CYCLES Matter within an ecosystem is recycled. (diagram of consumer--->decomposer--->soil--->producer--->consumer)

All Cycles Are Related All cycles are related. Diagram showing interaction of water, carbon, nitrogen, sulfur, phosphorus cycles. Just view that many things are being recycled. (Do not teach the cycles from this slide at this time. Repeated at end of slide show for review.)

BIOGEOCHEMICAL CYCLES Water, carbon, oxygen, nitrogen & other elements cycle from the abiotic (“geo” nonliving environment) to biotic (“bio” living organisms) & then back to the environment. biotic abiotic BIOGEOCHEMICAL CYCLES Water, carbon, oxygen, nitrogen & other elements cycle from the abiotic (“geo” nonliving environment) to biotic (“bio” living organisms) & then back to the environment.

BIOGEOCHEMICAL CYCLES Water, carbon, oxygen, nitrogen & other elements move through a regularly repeated sequence of events. Define a cycle. A cycle is a repeated sequence of events. H2O C N O BIOGEOCHEMICAL CYCLES Water, carbon, oxygen, nitrogen & other elements move through a regularly repeated sequence of events. Define a cycle. A cycle is a repeated sequence of events.

BIOGEOCHEMICAL CYCLES atmosphere “bank” Most element cycles have an atmospheric “bank” where the element is found in large amounts. BIOGEOCHEMICAL CYCLES (This slide series points out the repeated events in most cycles.) Most element cycles have an atmospheric “bank” where the element is found in large amounts. The soil and the ocean are additional major banks for some elements.

BIOGEOCHEMICAL CYCLES atmosphere “bank” Elements move from the “bank” into organisms. BIOGEOCHEMICAL CYCLES Elements move from the “bank” into organisms.

BIOGEOCHEMICAL CYCLES Organisms release elements in daily activities or after death. Give an example of an activity that releases elements. RIP atmosphere “bank” BIOGEOCHEMICAL CYCLES Organisms release elements in daily activities or after death. Give an example of an activity that releases elements. Examples vary - make sure respiration is one of them, others photosynthesis, transpiration, perspiring, excretion, digestion

BIOGEOCHEMICAL CYCLES Decomposers (or combustion or erosion) break down organic matter. What is a result of their actions? RIP atmosphere “bank” BIOGEOCHEMICAL CYCLES Decomposers (or combustion or erosion) break down organic matter. What is a result of their actions? The element is released back into the atmosphere bank.

BIOGEOCHEMICAL CYCLES Three example cycles: Water Carbon (carbon-oxygen) Nitrogen H2O C N O BIOGEOCHEMICAL CYCLES Three example cycles: Water Carbon (carbon-oxygen) Nitrogen

WATER CYCLE On your notes sheet, label the steps of the water cycle evaporation condensation precipitation transpiration (Have the students make a heading for Water Cycle and copy the words with space for) definition. WATER CYCLE Use the next diagram to help you define the following: evaporation condensation precipitation transpiration runoff accumulation

WATER CYCLE Evaporation – the process by which water changes from a liquid to a gas Condensation – water cools and condenses into tiny droplets Precipitation – rain, sleet, snow, or hail Transpiration – water evaporating from the leaves of plants (Have the students make a heading for Water Cycle and copy the words with space for) definition. WATER CYCLE Use the next diagram to help you define the following: evaporation condensation precipitation transpiration runoff accumulation

water cycle diagram water cycle diagram #1 Discuss the events and have the students write a brief description.

biotic abiotic WATER CYCLE Nonliving portions of the water cycle include condensation, evaporation & precipitation. WATER CYCLE Nonliving portions of the water cycle include condensation, evaporation & precipitation.

biotic abiotic WATER CYCLE Living portions of the water cycle include plants performing transpiration and water intake by all organisms. WATER CYCLE Living portions of the water cycle include plants performing transpiration and water intake by all organisms.

WATER CYCLE Water vapor exits plant leaves during transpiration through tiny openings called stomata. WATER CYCLE Water vapor exits plant leaves during transpiration through tiny openings called stomata.

WATER CYCLE Water loss from plant leaves during transpiration is caused in part by the sun’s heat energy in a process similar to the way we lose water when we perspire. WATER CYCLE Water loss from plant leaves during transpiration is caused in part by the sun’s heat energy in a process similar to the way we lose water when we perspire.

WATER CYCLE Water loss from plant leaves during transpiration is caused in part by the sun’s heat energy in a process similar to the way we lose water when we perspire. (slide repetition for animation)

WATER CYCLE Water loss from plant leaves during transpiration is caused in part by the sun’s heat energy in a process similar to the way we lose water when we perspire. (slide repetition for animation)

WATER CYCLE Water loss from plant leaves during transpiration is caused in part by the sun’s heat energy in a process similar to the way we lose water when we perspire. (slide repetition for animation)

WATER CYCLE Water loss from plant leaves during transpiration is caused in part by the sun’s heat energy in a process similar to the way we lose water when we perspire. (slide repetition for animation)

WATER CYCLE Why are water cycles said to be driven by the sun? (This is the first slide in an animation series.)

WATER CYCLE Why are water cycles said to be driven by the sun? (slide repetition for animation)

WATER CYCLE Why are water cycles said to be driven by the sun? (slide repetition for animation)

WATER CYCLE Why are water cycles said to be driven by the sun? (slide repetition for animation)

WATER CYCLE Why are water cycles said to be driven by the sun? (slide repetition for animation)

WATER CYCLE Why are water cycles said to be driven by the sun? (slide repetition for animation)

WATER CYCLE Why are water cycles said to be driven by the sun? (slide repetition for animation)

WATER CYCLE Why are water cycles said to be driven by the sun? (slide repetition for animation)

WATER CYCLE Why are water cycles said to be driven by the sun? (slide repetition for animation)

WATER CYCLE Why are water cycles said to be driven by the sun? Heat energy from the sun causes water to evaporate returning water vapor to the atmosphere.

WATER CYCLE What happens to water as heat energy from the sun warms it? WATER CYCLE What happened to the water as heat energy from the sun warmed it? The heat energy causes the liquid to change into a gas.

WATER CYCLE What would happen to water vapor in the air if it began to cool (loss of heat energy)? WATER CYCLE What would happen to water vapor in the air if it began to cool (loss of heat energy)? The water vapor comes together as tiny droplets that for clouds (condensation).

WATER CYCLE What would happen to water vapor in the air if it began to cool (loss of heat energy)? x WATER CYCLE What would happen to water vapor if it began to cool? As the vapor cools, heat is lost and the water molecules begin to collect together forming tiny droplets that may become visible as clouds or fog.

WATER CYCLE What would happen to water vapor in clouds if it began to cool even more? x WATER CYCLE What would happen to water vapor if it began to cool even more? As the water vapor cools more, additional heat is lost and the water molecules begin to collect together forming small drops that get bigger & bigger until they are too heavy and fall as precipitation.

water cycle diagram animated Review the cycle, using questioning to engage the students.

CARBON CYCLE All living things contain carbon. Carbon is found in carbohydrates, proteins, and lipids. Carbon dioxide is “banked” in the atmosphere CARBON CYCLE Why is the Carbon Cycle often called the Carbon-Oxygen Cycle? The carbon and oxygen are closely related in the formation of carbon dioxide which the way carbon is “banked” in the atmosphere. It is also sometimes called the carbon dioxide cycle.

CARBON CYCLE The Carbon Cycle is often called the Carbon-Oxygen. Why do you think this is? respiration photosynthesis O2 CO2 CARBON CYCLE Why is the Carbon Cycle often called the Carbon-Oxygen Cycle? The carbon and oxygen are closely related in the formation of carbon dioxide which the way carbon is “banked” in the atmosphere. It is also sometimes called the carbon dioxide cycle.

CARBON CYCLE How does carbon enter the living part of the cycle? CO2 CO2 CO2 CO2 CO2 CARBON CYCLE How does carbon enter the living part of the cycle? CO2 + H2O ----> C6H12O6 + O2 Carbon enters living portion of the carbon cycle through photosynthesis. CO2 CO2 CO2 CO2 + H2O ----> C6H12O6 + O2

CARBON CYCLE Carbon is returned to the atmosphere environment by: cellular respiration erosion combustion decomposition CARBON CYCLE Carbon returned to environment by: cellular respiration erosion combustion decomposition

CARBON CYCLE On your notes sheet, label the steps of the carbon cycle. respiration photosynthesis decomposition combustion erosion CARBON CYCLE Use the next diagram to help you define relationship of the following terms to the carbon cycle. respiration - CO2 is released back into the atmosphere when food (glucose) is broken down during respiration photosynthesis - CO2 is taken from the air and trapped into food (glucose) during photosynthesis decomposition - CO2 is released back into the atmosphere as organic matter is broken down during decomposition combustion - CO2 is released back into the atmosphere when organic material is burned (undergoes oxidation, similar to respiration ) erosion – CO2 is released back into the atmosphere when erosion breaks down rock such as limestone containing CaCO3 (calcium carbonate)

CARBON CYCLE

CARBON CYCLE Respiration - CO2 is released back into the atmosphere when food (glucose) is broken down during respiration Photosynthesis - CO2 is taken from the air and converted into food (glucose) Decomposition - CO2 is released back into the atmosphere as organic matter is broken down Combustion - CO2 is released back into the atmosphere when organic material is burned Erosion – CO2 is released back into the atmosphere when erosion breaks down rock such as limestone containing CaCO3(calcium carbonate)

CARBON CYCLE Like other element cycles, the carbon cycle links nonliving & living parts of the environment. biotic abiotic CARBON CYCLE Like other element cycles, the carbon cycle links nonliving & living parts of the environment.

CARBON CYCLE The exchange of gases during photosynthesis and respiration is a major example of the living-nonliving cycle of carbon-oxygen. respiration photosynthesis O2 CO2 CARBON CYCLE The exchange of gases during photosynthesis and respiration is a major example of the living-nonliving cycle of carbon-oxygen.

CARBON CYCLE CO2 in Atmosphere assimilation by plants factory animal respiration soil and organism respiration plant respiration photosynthesis by algae respiration by algae and aquatic animals CARBON CYCLE Discuss terms and what is happening at each directional arrow. (Have students note which arrow captures and which arrow releases carbon.) litter fossil fuels coal, gas, petroleum oceans, lakes limestone decomposition

Write a descriptive summary of the events shown. carbon cycle animated (carbon cycle animated) Write a descriptive summary of the events shown. Call the students attention to the major source of energy from the sun entering plants through photosynthesis. Have students write a description to summarize what they are seeing in the animation. (Allow 5 minutes) Have them focus on the paths of the colored dots and what would be occurring. Make sure you point out the transition from red to clear dots. (This is oxidation, I.e. respiration and combustion.) Paragraph summaries will vary but should include: white dots - carbon dioxide released from combustion (forest fire, burning fossil fuels), respiration (soil and plant & animal) blue dots - water, note how they collide with the white dots to represent photosynthesis green dots - carbon trapped in glucose from photosynthesis, note how green dots move through organisms then flash red to represent respiration red dots - represents respiration or combustion, note the red flash of green dots into white dots at soil respiration and animal & plant respiration, and the red flash into white at forest fire & burning of fossil fuels

N2 free nitrogen NITROGEN CYCLE 78% of the atmosphere is nitrogen gas but it is in a form most living things cannot use. N2 free nitrogen NITROGEN CYCLE 79% of the atmosphere is nitrogen gas but it is in a form most living things cannot use.

NITROGEN CYCLE If we can’t take in free nitrogen, how do we acquire it so we can use it in our bodies? Why do we need nitrogen in our bodies? NITROGEN CYCLE If we can’t take in free nitrogen, how do we acquire it so we can use it in our bodies? Why do we need nitrogen in our bodies? (Don’t answer these now – they lead to next item.)

NITROGEN CYCLE How do we acquire usable nitrogen? Nitrogen-fixing bacteria convert nitrogen into nitrates. Plants absorb nitrates. Animals eat plants. NITROGEN CYCLE How do we acquire usable nitrogen? Nitrogen-fixing bacteria convert nitrogen into nitrates. Plants absorb nitrates. Animals eat plants. N2 in air nitrogen-fixing bacteria NITRATES

NITROGEN CYCLE How does the nitrogen return to the atmosphere? Denitrifying bacteria convert the nitrates back into nitrogen. denitrifying bacteria NITROGEN CYCLE How does the nitrogen return to the atmosphere? Denitrifying bacteria convert the nitrates back into nitrogen. N2 in air nitrogen-fixing bacteria NITRATES

? NITROGEN CYCLE Why do we need nitrogen? protein Nitrogen Nitrogen is an essential element for all proteins (amino acids) and nucleic acids. ? Nitrogen

NITROGEN CYCLE Can plants & animals use free nitrogen? In what form must N2 be to be used by plants? What organisms can fix the N2 into a usable form? nitrates NITROGEN CYCLE Can plants & animals use free nitrogen? plants & animals cannot use free nitrogen in the atmosphere In what form must N2 be to be used by plants? nitrates What organisms can fix the N2 into a usable form? nitrogen-fixing bacteria nitrogen-fixing bacteria

NITROGEN CYCLE Simplified Free N2 in Atmosphere denitrifying bacteria nitrogen-fixing bacteria NITROGEN CYCLE SIMPLIFIED diagram of nitrogen cycle Discuss the diagram and have student label on their handout. RIP Organic material NITRATES

NITROGEN CYCLE lightning fixes N2 into nitrates nitrates denitrifying diagram of nitrogen cycle Review the events in the nitrogen cycle. denitrifying bacteria nitrates organic matter nitrogen-fixing bacteria

Reviewing the Cycles WATER CYCLE evaporation condensation precipitation transpiration Reviewing the Cycles WATER CYCLE evaporation condensation precipitation transpiration

Reviewing the Cycles CARBON CYCLE photosynthesis-respiration combustion erosion decomposition RIP atmosphere “bank” Reviewing the Cycles CARBON CYCLE photosynthesis-respiration combustion erosion decomposition

Reviewing the Cycles NITROGEN CYCLE nitrogen-fixing bacteria nitrates decomposition denitrification Free N2 in Atmosphere denitrifying bacteria nitrogen-fixing bacteria Reviewing the Cycles NITROGEN CYCLE nitrates nitrogen-fixing bacteria denitrification decomposition RIP Organic material NITRATES

Cycle Interrelationships Point put parts of each cycle and have students identify the event and cycle(s)