p. 22-32

Biogeochemical Cycles - The movement of matter through the biotic and abiotic environment.

Examples:

The Water Cycle &The Carbon Cycle & The Nitrogen Cycle

Nutrients: substances made of elements that an organism use to build and repair the cells of its body

The Water CycleThe Water Cycle

1.1. Liquid water Liquid water evaporatesevaporates and rises into the and rises into the atmosphereatmosphere

2.2. The water vapour The water vapour condensescondenses, forming liquid , forming liquid water or ice crystals (depending on the air water or ice crystals (depending on the air temperature) and returns to the earth as rain, temperature) and returns to the earth as rain, hail or snowhail or snow

3.3. Water falling on land may enter the soil and Water falling on land may enter the soil and ground water or move across the surface ground water or move across the surface entering lakes, rivers, and oceans.entering lakes, rivers, and oceans.

The Water CycleThe Water Cycle

4.4. Water that is taken in by plant roots may be Water that is taken in by plant roots may be released from leaves through released from leaves through transpirationtranspiration

5.5. Animals take in water when they drinking or Animals take in water when they drinking or consume food. Water is returned to the consume food. Water is returned to the environment from skin (environment from skin (perspirationperspiration), from lungs ), from lungs (exhaled) and in wastes (exhaled) and in wastes

6.6. Most of the water that is present in the water Most of the water that is present in the water cycle is in the abiotic environmentcycle is in the abiotic environment

The Water CycleThe Water Cycle

Bill Nye Water Cycle Video.mp4Bill Nye Water Cycle Video.mp4

Magic School Bus Water Cycle Video.mp4Magic School Bus Water Cycle Video.mp4

The Nitrogen CycleThe Nitrogen CycleWhy is nitrogen important to life? Why is nitrogen important to life?  ALL organisms need nitrogen to make ALL organisms need nitrogen to make

proteins proteins Plants and animals could not live Plants and animals could not live without nitrogen. without nitrogen.

It is an important part of many cells and It is an important part of many cells and processes such as amino acids, proteins, and processes such as amino acids, proteins, and even our DNA. It is also needed to make even our DNA. It is also needed to make chlorophyll in plants, which plants use in chlorophyll in plants, which plants use in photosynthesis to make their food and energy. photosynthesis to make their food and energy. 

Nitrogen makes up 78% of the Nitrogen makes up 78% of the atmosphere but cannot be used atmosphere but cannot be used DIRECTLY by most organismsDIRECTLY by most organisms

Get most from ammonia; converting Get most from ammonia; converting nitrogen gas to ammonia is called nitrogen nitrogen gas to ammonia is called nitrogen fixationfixation

Bacteria do this and without them nitrogen Bacteria do this and without them nitrogen cycling would stopcycling would stop

Lightning is the only other natural nitrogen Lightning is the only other natural nitrogen fixing process (only 1% of world’s nitrogen fixing process (only 1% of world’s nitrogen fixing)fixing)

Processes in the Nitrogen CycleProcesses in the Nitrogen CycleFixation:Fixation: is the first step of making nitrogen usable by is the first step of making nitrogen usable by

plants. Here bacteria change nitrogen into ammonium.plants. Here bacteria change nitrogen into ammonium.

NitrificationNitrification:: ammonium gets changed into nitrates by ammonium gets changed into nitrates by bacteria. Nitrates are what the plants can then absorb.bacteria. Nitrates are what the plants can then absorb.

Assimilation:Assimilation: is how plants get nitrogen; they absorb is how plants get nitrogen; they absorb nitrates from the soil into their roots. Then the nitrogen nitrates from the soil into their roots. Then the nitrogen usedused

Ammonification: Ammonification: decaying process; when a plant/animal decaying process; when a plant/animal dies, decomposers like fungi and bacteria turn the dies, decomposers like fungi and bacteria turn the nitrogen back into ammonium so it can reenter the nitrogen back into ammonium so it can reenter the nitrogen cycle.nitrogen cycle.

Denitrification Denitrification - Extra nitrogen in the soil put back out into - Extra nitrogen in the soil put back out into the air by other bacteriathe air by other bacteria

The Carbon CycleThe Carbon Cycle• All life based on carbon.

• Building block of all living things.

• Present as CO2 in the atmosphere and dissolved in the oceans.

The Carbon CycleThe Carbon Cycle

• Relationship between photosynthesis and respiration.

• During photosynthesis, plants use CO2 to produce sugar

• During respiration, consumers eat the plants and release CO2 back into the atmosphere.

PHOTOSYNTHESIS (sugar)

CO2 + H2O + light energy C6H12O6 + O2

PHOTOSYNTHESIS (sugar)

CO2 + H2O + light energy C6H12O6 + O2

CELLULAR RESPIRATIONCELLULAR RESPIRATION C6H12O6 + O2 CO2 + H2O + energy CELLULAR RESPIRATIONCELLULAR RESPIRATION C6H12O6 + O2 CO2 + H2O + energy

Here’s how it Here’s how it works….works….

Plants use CO2 to make food, so

carbon is now in the PRODUCERS.

Carbon (as CO2) is in the atmosphere

or water.

Plants & animals respirate, which returns

CO2 to the atmosphere or water.

Herbivores eat plants and carnivores eat herbivores, so now

carbon is in the CONSUMERS.

DECOMPOSERS break down dead plants

& animals, returning CO2 to the atmosphere

or water.

Figure 4, p. 50

Carbon Deposits

Most of the earth’s carbon is not cycled – it is stored in carbon rich deposits.

Earth’s Crust/Soil Layers of bones & shells from living things form rock. This carbon can be trapped for millions of years until geological conditions release it (erosion, volcano).

Fossil fuels (coal, oil, and natural gas) are most valuable carbon deposits

Energy Flow inEnergy Flow in Ecosystems Ecosystems

Source of all energy for ecosystems Source of all energy for ecosystems

Plants use the sun’s energy for Plants use the sun’s energy for photosynthesis (to make food, which later photosynthesis (to make food, which later serves as an energy source for other serves as an energy source for other organisms).organisms).

The distribution of incoming solar radiationThe distribution of incoming solar radiation

Chemical EnergyChemical Energy can be stored can be stored in cells and then released when in cells and then released when needed.needed.

Chemical energy is used by all Chemical energy is used by all organisms to perform functions, organisms to perform functions, including movement, growth, and including movement, growth, and reproductionreproduction..

carbon dioxide + water sugar + oxygen

Where does Chemical Energy used by Where does Chemical Energy used by organisms come from?organisms come from?

Photosynthesis Photosynthesis – the process in which the – the process in which the Sun’s energy is converted into chemical energySun’s energy is converted into chemical energy

LIGHT ENERGYLIGHT ENERGY

Photosynthesis Word Equation:

Sugar (stored Sugar (stored chemical energy) is chemical energy) is stored in roots, stems, stored in roots, stems, leaves and seeds of leaves and seeds of plants. Figure 3plants. Figure 3

Some sugars are Some sugars are used as building used as building materials (not all materials (not all sugar goes toward sugar goes toward energy storage). energy storage).

Producers vs. ConsumersProducers vs. Consumers

ProducerProducer – an organism that makes its – an organism that makes its own energy – rich food compounds using own energy – rich food compounds using the Sun’s energy (via photosynthesis)the Sun’s energy (via photosynthesis)

• Example: plants and algae (their green colour Example: plants and algae (their green colour comes from a chemical called chlorophyll, which comes from a chemical called chlorophyll, which captures light energy)captures light energy)

Producers vs. ConsumersProducers vs. Consumers

ConsumersConsumers obtain obtain energy and building energy and building materials by eating materials by eating other organisms.other organisms. Example: Humans Example: Humans

are consumers, are consumers, obtaining energy by obtaining energy by eating other eating other organisms.organisms.

Photosynthesis produces stored energy in Photosynthesis produces stored energy in the form of sugar. the form of sugar.

To make stored energy available for use, To make stored energy available for use, the plant undergoes Cellular Respiration.the plant undergoes Cellular Respiration.

Cellular RespirationCellular Respiration: a chemical process : a chemical process by which sugar is converted into carbon by which sugar is converted into carbon dioxide, water and energy.dioxide, water and energy.

Cellular Respiration Word Equation:

sugar + oxygen carbon dioxide + water + energy

Photosynthesis and cellular respiration are complementary Photosynthesis and cellular respiration are complementary processes.processes.

PHOTOSYNTHESISPHOTOSYNTHESIScarbon dioxide + water sugar + oxygenPHOTOSYNTHESISPHOTOSYNTHESIScarbon dioxide + water sugar + oxygen

CELLULAR RESPIRATION CELLULAR RESPIRATION sugar + oxygen carbon dioxide + water + energyCELLULAR RESPIRATION CELLULAR RESPIRATION sugar + oxygen carbon dioxide + water + energy

***Complementary processes since the products of one reaction are needed as reactants for the other process. Provides us with evidence that we depend on other living organisms

sunlight

..

Types of ConsumersTypes of Consumers

Detrivores:Detrivores: consumers that feed on organic matter (Organic matter: is the remains of a dead organism and animal consumers that feed on organic matter (Organic matter: is the remains of a dead organism and animal wastes)wastes)

Every organism within an ecosystem provides energy Every organism within an ecosystem provides energy for other organisms.for other organisms.

Food Chains:Food Chains: a step-by-step sequence of who eats a step-by-step sequence of who eats whom in an ecosystem, showing how energy is whom in an ecosystem, showing how energy is transferred from one organism to another. transferred from one organism to another.

Example: Example:

The final carnivore in any food chain is called a The final carnivore in any food chain is called a top carnivore.top carnivore.

All organisms continuously use and release energy to All organisms continuously use and release energy to their environment. This means that energy is their environment. This means that energy is continuously lost from all levels of the food chain.continuously lost from all levels of the food chain.

..

Figure 3, p. 43 A simple food chain in a forest ecosystem (arrows show how energy is transferred)

.. Trophic Levels: a method of categorizing living Trophic Levels: a method of categorizing living

things according to how they gain their energy.things according to how they gain their energy. FirstFirst trophic level contains trophic level contains producersproducers and each and each

higherhigher level contains level contains consumersconsumers. .

Less energyLess energy 33rdrd trophic level trophic level 22ndnd trophic level trophic level

11stst trophic level trophic level More energyMore energy

THIRD TROPHIC LEVELTHIRD TROPHIC LEVELSecondary ConsumersSecondary Consumers – rely on – rely on primary consumers for energy but primary consumers for energy but they’re still dependent (indirectly) they’re still dependent (indirectly)

on producers.on producers.

SECOND TROPHIC LEVELSECOND TROPHIC LEVELPrimary ConsumersPrimary Consumers - organisms that - organisms that

feed on producers, rely on them feed on producers, rely on them directly for energy.directly for energy.

FIRST TROPHIC LEVELFIRST TROPHIC LEVELProducersProducers- make their own food.- make their own food.

Ex. Plants, algae, some bacteria Ex. Plants, algae, some bacteria

.. Food WebFood Web: A graphical : A graphical

representation showing the representation showing the many feeding relationships many feeding relationships among organisms in an among organisms in an ecosystem. ecosystem.

Many food chains Many food chains combined.combined.

Food webs are useful tools Food webs are useful tools to figure out what may to figure out what may happen when a species is happen when a species is removed or added to an removed or added to an ecosystemecosystem

Greatest Greatest biodiversitybiodiversity

Complex food Complex food webs…if one webs…if one organism is organism is completely completely removed, it will removed, it will have minimal have minimal effect on the effect on the overall web.overall web.

Ex: Rainforest

Ecosystems with less biodiversity Ecosystems with less biodiversity have simpler food webs. have simpler food webs.

If one organism is lost, there is a If one organism is lost, there is a profound effect on all remaining profound effect on all remaining organismsorganisms..

Ex. Arctic few producers because of low temperatures and little energy from the sun. Less energy is available so few organisms can live here, making them more vulnerable.

Ecological PyramidsEcological Pyramids display relationships display relationships between trophic levels between trophic levels in ecosystems.in ecosystems.

Pyramid of EnergyPyramid of Energy illustrate illustrate energy loss and energy loss and transfer between transfer between trophic levelstrophic levels

Most of the sun’s energy that plants absorb is used and the rest is stored.Most of the sun’s energy that plants absorb is used and the rest is stored.

Consumers eat the plants, gaining the stored energy. Consumers eat the plants, gaining the stored energy.

This energy is used for life activities, so the consumers store even less This energy is used for life activities, so the consumers store even less energy. energy.

During any energy change, some energy is converted into an unusable During any energy change, some energy is converted into an unusable form, form, heatheat that cannot be passed on (thus, some more energy is lost). that cannot be passed on (thus, some more energy is lost).

As a result, the farther up the food chain you travel, the As a result, the farther up the food chain you travel, the less energyless energy available. available.

Only about 10% of energy is transferred to the next trophic level. Only about 10% of energy is transferred to the next trophic level.

Pyramid of Energydrawn by measuring the amount of energyavailable at each trophic level

•Only 10% of the total energy is passed to each level. •Therefore, as you move up the food chain, there is less energy available. •Animals located at the top of the food chain need a lot more food to meet their energy needs.

The number of trophic levels in a food The number of trophic levels in a food chain is limited to chain is limited to five.five.

Since overall loss of energy at each Since overall loss of energy at each step is so large, there won’t be enough step is so large, there won’t be enough energy to support a higher-level energy to support a higher-level consumerconsumer..

HOMEWORKHOMEWORK

Read and supplement notes 1.2Read and supplement notes 1.2 Complete ?’s p. 35 #2-6, 12, 13, 15Complete ?’s p. 35 #2-6, 12, 13, 15