Do you remember stretching out on your stomach in the grass to watch a parade of ants as they carried food particles and debris along a path that seemed endless to a final destination that only they knew about? It was pretty amazing, wasn’t it?
Those ants seemed to be on a mission that only they understood, and they never seemed to get tired or stray off the path. They just marched on to a beat that only they could hear. Sometimes they carried bits of grass or tiny particles of dirt. Occasionally, they would carry a dead ant with them as well.
It was fascinating, but what they did and where they were going — and why — was always a mystery.
Watching them was my first experience with one of the earth’s ecosystems, in the hot, dusty, arid environment of eastern Montana. I watched those ant parades for hours. I set up barricades.
I left grains of sugar in their path, and sometimes bigger things — a leaf, or a pebble, or even a bottle cap full of water. Sometimes I even stepped on one or two, just to see what the others would do. The ants just kept going, even if they had to climb the “mountains” or cross the “rivers” that I put in their way.
I remember that they seemed to work all day, but they disappeared at dusk, only to be there again the next morning. Sometimes I wondered where they went at night and how they survived during the long winters.
I have since visited other ecosystems: rainforests in the Pacific Northwest, where the air is thick with humidity, and everything seems to be green and lush, and hot, dry deserts in the Southwest where it seems that nothing could survive.
But even deserts are full of creatures that have adapted to the environment, and cactus blooms are among the prettiest flowers anywhere. I have also visited sandy beaches and snow-covered mountain tops where life exists in different forms, and I have gone swimming in oceans filled with coral reefs and brightly colored fish.
In short, I have traveled to many of the earth’s distinctive ecosystems. Those early encounters with ant parades were my first introduction to the endless cycle of birth and growth, decay, and death that, in effect, makes our world what it is.
Facts About Ecosystems
- Many different ecosystems exist.
- All ecosystems contain living organisms.
- Live organisms in an ecosystem are called biomes.
- Ecosystems react slowly to change.
- Healthy ecosystems have great biodiversity.
- Ecosystem changes can have global effects.
- The earth is one giant ecosystem.
So, What Is an Ecosystem, Exactly?
The simple definition of an ecosystem, or ecological “community,” is that it comprises a group of living organisms that live in harmony with their surrounding natural, non-organic (or non-living) environment.
A “healthy” ecosystem contains all the components needed to sustain and nourish the cycle of life, specifically the necessary energy and nutrients, and when they are in balance, the entire community thrives.
The term ecosystem was first used in 1935 by an English botanist, A.G. Tansley, to describe the interaction between living organisms and non-living environments.
Changes can occur within any distinct ecosystem, but they typically happen slowly, and sometimes they do not become evident for centuries or even thousands of years.
Within ecosystems, however, the diversity of living species can be enormous. Such biodiversity must be maintained in order to nurture the specific plants and animals that exist within the environment.
What Are the Different Types of Ecosystems?
Aquatic Ecosystems are of two basic types: Freshwater systems that include lakes, rivers, and streams, and Marine ecosystems that exist in the oceans and salt-water seas and marshes throughout the world. Individual ecosystems can be very limited in the territory, or they may exist over thousands of miles.
Terrestrial Ecosystems are land-based and are typically characterized by limited sources of water to support animal and plant life. They include:
- Forest: These ecosystems may differ greatly, based on their physical location, from tropical rain forests to high-altitude temperate forests with old-growth pines or deciduous trees. The animal populations differ as well.
- Grassland: Characterized by native grasses and small shrubs, grasslands include savannas that exist between forest and desert biomes, as well as cultivated farmland used to produce food.
- Desert: With hot days and cold nights, desert ecosystems are found throughout the world.
- Tundra: With minimal rainfall and often extremely cold temperatures, tundra ecosystems include the Arctic regions, snow-covered mountain ranges, and vast stretches of land that are devoid of trees and usually considered unsustainable for human life.
Why Are Ecosystems Important?
An ecosystem can be any community that includes living creatures — including humans — and the organisms and natural surroundings that support their existence.
In truth, the earth and its people, plants, and animals are one big ecosystem, but scientists, environmentalists, and historians study smaller and more specific ecological systems to understand the relationships between living creatures and their environments. Living organisms interact with and influence their locations in unique ways.
As the earth’s population expands, more and more natural environments must be used to house and produce food for the growing number of people. With the growth of cities and the associated destruction of some natural environments, or ecosystems, worrisome changes have been identified. Studying the earth’s existing ecosystems may provide important clues about the future of life on earth.
How Does an Ecosystem Function?
The earth is made up of living organisms of various kinds and the non-living environment, including the rocks and dirt, the mountains and rivers that are found on earth.
There are numerous micro-climates and hundreds of millions of species, from microbes to dinosaurs, from bees to bears, and from tiny tundra flowers to giant redwoods, that have populated the earth throughout history.
A biome is a term applied to the groups of living organisms that exist within a specific environment. An ecosystem includes the biome as well as the “abiotic” or non-living environment.
It also encompasses the energy and the climate that sustain each unique location. Tracing the movements and the relationship between energy and matter in any ecosystem is incredibly important to help us understand the continually evolving relationships.
An endless cycle of birth, growth, and renewal is balanced by a similar cycle of aging, death, decay, and transformation.
Learning About Ecosystems
When I was older still, I was fascinated with the woods near my home and by the variety of life that was waiting to be discovered — decaying bark, moldy leaves, moss on the sides of trees, mushrooms growing in the shade, and some creepy-crawlies that looked like creatures from outer space.
And then there were the birds and the spiders, the webs and the worms, the chipmunks and the butterflies, and a whole universe of life that existed without any help from me.
Creatures took care of themselves; they did not need to be fed or walked or taken to the vet. They were the inhabitants of a world that I knew little about. But I knew that there were natural worlds waiting to be discovered!
They were — and are — important participants in the earth’s ecosystems, “communities” of living things that include trees and animals, plants and energy, air and water, and the life process that transforms energy into matter.
This understanding is vitally important to the entire world. Understanding a forest ecosystem or learning how coral reefs help sustain the marine ecosystem is important.
Knowing these things may help solve some of the issues of climate, pollution, and resource management.
Ecosystems and Biodiversity
Without distinctive ecosystems, human life on earth would not exist in the way it now is lived. The diversity of life on this planet — both animal and plant life, is immense.
According to the BBC, a fairly accurate estimate of the number of distinct animal species on earth was set at 8.7 million in 2011! However, most of them have not been identified, and it was estimated that cataloging them all might take 1,000 years.
However, scientists warn that, without serious efforts to change current trends, the biodiversity that sustains important ecosystems will disappear. Ecosystem relationships are still not totally understood, but scientists all over the world are currently hard at work finding and describing existing plant and animal species, identifying at-risk populations, and understanding how the planet’s ecosystems are interrelated.
Our earth’s ecosystems, while separate and distinct, are intertwined; what affects a forest ecosystem will inevitably have an impact on the ecosystem of the oceans, and changes that occur in a desert ecosystem will eventually affect the rivers and streams that flow across the earth’s surface. The goal is to find a way to balance the giant ecosystem that is the earth.