Four Systems
of
Our
Earth
Composition of Earth Earth Has 4 main systems that interact:
Earth’s systems
Atmosphere Hydrosphere Biosphere Geosphere
water life land/rockAir/gases
Composition of Earth Earth Has 4 main systems that interact:
The Atmosphere The Hydrosphere The Biosphere
Life on Earth Sea life, plants, flying creatures, humans Encompasses hydrosphere, upper geosphere, and
lower atmosphere. The Geosphere
BIOSPHERE
The relationship between an organism and its environment is the study of ecology.
Living things interact with Non living things in the Biosphere
Biotic Factors—living components in the biosphere
Biotic, meaning of or related to life, are living factors. Plants, animals, fungi, protist and bacteria are all biotic or living factors.
Living things interact with Non living things in the Biosphere
AbioticAbiotic Factors—nonliving components in the biosphere
Environmental factors such habitat (pond, lake, ocean, desert, mountain) or weather such as temperature, cloud cover, rain, snow, hurricanes, etc. are abiotic factors.
Role of Water in the Biosphere
Water is the universal solvent and the basis of all life on our Planet.
The hydrosphere is important to the Biosphere!
Role of the Sun for the biosphere
The Sun provides the light and heat necessary to maintain life on Earth and is the ultimate source of energy.
Biotic and abiotic factors combine to create a system or more precisely, an ecosystem.
An ecosystem is a community of living and nonliving things.
Examples of ecosystems A pond. Abiotic factors? Biotic Factors?
Ocean Ecosystem Abiotic? Biotic?
Grassland ecosystem
The Impact of Changing Factors
If a single factor is changed, perhaps by pollution or natural phenomenon, the whole system could be altered.
For example, humans can alter environments through farming or irrigating. While we usually cannot see what we are doing to various ecosystems, the impact is being felt all over.
For example, acid rain in certain regions has resulted in the decline of fish population.
A food chain Shows how each living thing gets its food. Some animals eat plants and some animals eat other
animals. For example, a simple food chain links the trees, the
giraffes and the lions. Each link in this chain is food for the next link. A food chain always starts with plant life and ends with an animal.
A food chain
An is added and means “is eaten by”; also shows the flow of energy (the giraffe gets his energy from the leaves)
Now we have made a simple food chain.
Biosphere Here is an
example of another food chain.
Plants are called producers or autotrophs because they are able to use light energy to make their own food.
Animals cannot make their own food so they must eat plants and/or other animals. They are called consumers or heterotrophs. There are three groups of consumers.
Herbivores are animals that only eat plants or plant products (seeds). They are also called primary consumers
Carnivores are animals that eat other animals.
There are 2 kinds of carnivores
Secondary Consumers are carnivores that eat herbivores
Herbivores are primary consumers
Something that makes its own food is called a producer
Tertiary consumers are carnivores that eat other carnivores
killer whales (tertiary consumer—they eat another carnivore)
Dolphin (secondary consumer—they eat a herbivore)
Herring (primary consumer—they only eat plants)
Photoplankton (this plant produces its own food)
Make your own food chain
Find in your notes where it says to make your own food chain.
Start with a plant on the very left side. The arrow means “is eaten by” so think of the
next thing that might eat your plant…and so on.
Animals and people who eat BOTH animals and plants are called omnivores
WE EAT PLANTS WE EAT MEAT
To sum up:
Animals that eat only plants.
Animals that eat only animals.
Animals that eat both animals AND plants. Humans are also omnivores!
Then there are decomposers (bacteria, worms, and fungi) which feed on decaying matter.
These decomposers speed up the decaying process that releases mineral salts back into the food chain for absorption by plants as nutrients.
Do you know why there are more herbivores than carnivores?
In a food chain, energy is passed from one link to another
Lets say a plant has the # 100 to represent the energy it has made.
When a herbivore eats, it does not get all the plant’s energy. It uses up some of the energy in everyday activities. The herbivore may only get 10% of that energy.
A carnivore then eats this herbivore. The carnivore only gets 1% of that plants original energy. This is why the carnivore has to eat many herbivores to get enough energy to grow.
Energy and mass is transferred from one level of the food chain to the next with an efficiency of about 10%.
Because of the large amount of energy that is lost at each link, the amount of energy that is transferred gets lesser and lesser
The further along the food chain you go, the less food (and energy) remains available.
ENERGY’S MOVEMENT IN THE FOOD CHAIN
This energy pyramid shows many trees & shrubs providing food and energy to giraffes.
Note that as we go up, there are fewer giraffes than trees & shrubs and even fewer lions than giraffes
... as we go further along a food chain, there are fewer and fewer consumers.
In other words, a large mass of living things at the base is required to support a few at the top ... many herbivores are needed to support a few carnivores
Most food chains have no more than four or five links
There cannot be too many links in a single food chain because the animals at the end of the chain would not get enough food (and hence energy) to stay alive.
Most animals are part of more than one food chain and eat more than one kind of food in order to meet their food and energy requirements. These interconnected food chains form a food web.
FOOD CHAIN vs FOOD WEB
FOOD CHAIN
FOOD WEB
Note that the arrows are drawn from food source to food consumers ...
substitute the arrows with the words "eaten by"
The arrows also show the way energy is moving.
Recap The sun is the source of energy Water is the source of life on earth Water is in the hydrosphere, geosphere and
atmosphere, and biosphere. The living things in the biosphere are dependent on
many nonliving things. (abiotic and biotic) There are food chains and webs that show what
animals eat. The higher up on the food chain, the less predators they have.
Be able to describe who receives the most of the sun’s energy and how energy moves and is converted through the food chain.
Be able to describe how the systems are connected (atmosphere, hydrosphere, and biosphere)