The world around us is slowly and constantly changing. We might never see the small alterations happen, but many years later changes will surly be visible. Over time small changes add up and soon the whole ecosystem is different. This slow change in the land and habitat is called ecological succession. Animals, plants, and weather are some factors that cause this type of change in an ecosystem.
Ecological succession begins with a pioneer community. In many cases lichens are the “pioneers.” Lichens break down rocks, making soil, so that plants can begin to grow. The process then continues on; trees grow, decay and then new trees grow back even bigger. Differences in the amount of sunlight, the amount of wind, and the type of soil all influence this changing community of organisms. The number and type of organisms change along with the habitat. Many, many years later the ecosystem becomes relatively stable. This stable condition can last for hundreds of years and is called a climax community.
Sometimes nature’s power causes changes that happen more quickly, but not instantly. An example of this is repeated flooding. In some areas floods happen often, each time new sediment is carried by the water and the deposited. Over time a marsh habitat becomes present, next a grassland and then a forest.
At other time nature works backwards by tearing down a climax community with a flood or fire. New kinds of organisms are able to move in and the process repeats its self. This type of major reorganization helps encourage diversity in the environment.
The next time you look outside try to picture a changing world. What you see out there today might not be the same in fifty years. Animals will move according to the food supply. Plants will die if they don’t get the right amount of sunlight and water. The ecosystem will adjust to the new situation.