REAL TREES 4 Kids! - What's the System

What's the System?

The more you observe the world around you, the more you will realize that nothing works in isolation. Everything (and everyone) is part of a bigger picture. Everything and everyone is part of one or more systems.

Think, for a minute, about some of the systems you know.

digestive system

nervous system

legal system

Interstate highway system

Criminal justice system

operating system

solar system

navigation systems

metric system

National Park System

Immune system

school system

Now, look at this example.

Your body needs the food that is sold at your neighborhood grocery. You can't drive to the store without encountering traffic lights. Traffic lights are useless unless there is a need to safely move traffic. This pattern could go on and on, but let's stop there and look at what we have.

Your body is made up of several systems.
The store is part of an economic system.
The traffic lights are part of a transportation system.
You, the store, and the traffic lights are all part of an ecosystem.

Systems are a group of parts that, when combined, make a whole. When you go to the store, all of the necessary systems connect and work together. It's simple and very complex all at the same time!

As in our example above, there are multiple systems in action on a REAL TREE operation. In fact, a REAL TREE operation is actually a system in itself — an ecosystem!

Ecosystem

The earth is a living system. The living world of the earth is called the biosphere. It is the region of the earth that supports life. The biosphere is so complex that ecologists and other scientists break it down into smaller units to study. The smaller units are called ecosystems. Although they are more simple to study than the biosphere as a whole, ecosystems are incredibly complex. Ecosystems are defined by the interaction of organisms and their environment. Everything in an ecosystem in connected in some way.
Ecosystems are made up of biotic and abiotic components.
The biotic elements of the ecosystem on a REAL TREE operation might include:
trees weeds insects deer chipmunks	chickadees owls grasses shrub flowers man
The abiotic elements of the ecosystem on a REAL TREE operation might include:
water sunlight soil pesticides rocks	temperature weather machinery buildings

Ecosystems do not exist in isolation. One ecosystem is connected to another in many ways. Some connections are obvious, others are not.

An owl, for example, may make its home in a wooded forest area that is located close to a REAL TREE operation. That owl is very much a part of the forest ecosystem where it makes its home. However, in hunting for prey, that owl may cross into the farm ecosystem. When this happens, ecosystems connect.

Physical features of an ecosystem also create connections. A river or stream running through a small town, may pass through farmland and through a woodland area before emptying into a freshwater lake. That river is an important part of each of those ecosystems. A change in the river (or in any of the ecosystems) causes a ripple effect. All of the ecosystems and their inhabitants are effected.

These connections, along with changing weather patterns and geologic events, mean that ecosystems are not static. They experience change over time. This slow, predictable change is called ecological succession.

Every so often, the slow and predicable pattern of succession is interrupted by a major event. At that point, the rate at which change occurs is increased for a time.

For example, a strong storm system in the southeastern United States disrupts multiple ecosystems in one fell swoop. Citizens of a small town are displaced as a tornado destroys their homes. Trees are uprooted by high winds causing animals to search for a new habitat. The rain associated with the storm causes flooding of rivers and streams. The excess water causes some plants to die while others experience very quick growth.

All of these changes will trigger rapid change in an ecosystem. The plants and animals that make up that system will adjust, adapt, or relocate. The predicable pattern is interrupted until a new predictable pattern emerges.

Community and Niche

Within ecosystems, organisms live in communities. A community is a group of animals and plants that live together in the same environment.

Communities can be small or large. The community on a REAL TREE operation, for example, might be considered a small, local community. That is, it exists on a small area of land and is likely surrounded by other communities sharing the same climate features.

In contrast, the term "deciduous forest" describes a very large community. Deciduous forests usually cover a great deal of land. Members of this large community are determined by climate.

When a community takes up large amounts of space and climate determines which plants and animals live there, the community is called a biome.

Within each community or biome, each species plays a very specific role. Individual species interact with the environment differently. This role and these interactions are called a niche.

For example, the interactions between a Colorado blue spruce interacts in a certain way to

the soil in which it is planted,
the animals that use it for shelter or food,
the amount of sun available,
the amount of water or moisture available, and
the climate (weather) of the area.

Those interactions are its way of life.

In a community, no two species can occupy the same niche. In other words, no two species can interact with environment in the exact same way. Some ecologists believe that if this were to happen, one of the species would die out due to competition. Other scientists have concluded that each niche (or role) is so specific that no two species are physically able to occupy the same niche.

Population

Another way to study an ecosystem is to look at the populations living within it. A population is a group of the same species of organism living in one area at the same time.

For example, on a REAL TREE operation, you find multiple populations. Certainly you would expect to find a population of a certain species of tree. Depending on the size of the operation, you might encounter several populations of REAL TREE.

Depending on the location, you could also expect to find a population of ants, chipmunks, chickadees, and grasses.

A population in a community will grow until it is limited by some factor. There are many of these limiting factors in an ecosystem. Food and shelter are two of them. When the populations of a community are using the resources of that community to the fullest extent, the environment's carrying capacity has been reached. At that point, if another species moves (or is moved) into the community, population changes will inevitably occur. The type of changes will depend upon the niche of the new population.

Producers and Consumers — Energy and Nutrients

When you get to the species level of this ecological organization system, you can discover the importance of each species and its specific niche within the community. These roles (and how well they are carried out) determine if the system is healthy and successful — or not!

All organisms within an ecosystem require energy. Unlike carbon, nitrogen, water, and nutrients, energy can't be recycled. Once it is used, it's gone.

Instead of being a cycle in a system, energy is described as flowing through a system.

In order to see how this works, individuals within a system need to be classified as autotrophs (producers) or heterotrophs (consumers). Autotrophs are those organisms that produce their own food. Heterotrophs are organisms that must get their energy by eating other organisms. It's the organisms of a system that keep the energy flowing.

The energy flow into an ecosystem begins with the sun.

Almost all organisms get needed energy directly or indirectly from the sun. Primary producers use the sun's energy in the process of photosynthesis. These producers are eaten by primary consumers. When this happens the sun's energy, in the form of carbohydrate, flows from producer to consumer.

Primary consumers become food for secondary consumers. When this happens, another energy transfer occurs. Should the secondary consumer become the prey of another (a tertiary consumer), the energy is transferred again. The pattern continues until it's time for the decomposers to do their work. At this point, dead organisms are returned to the soil as simple nutrients.

Energy flow through a system is often called the food chain. In an ecosystem, there are often multiple food chains. As food chains overlap and become increasingly complex, ecologists describe them as food webs.

The System

So, what's the system? It's a complex, always in motion, always adapting and adjusting, interconnected, interdependent world to live in. That's quite a bit. However, if you look closer, there's even more to it than that! From a city street, to your backyard, to a REAL TREE operation, to a river system, to a deciduous forest, to the densest rainforests of the world ... ecosystems also provide a way to organize, describe, and understand what we know about the world in which we live!