Which Factors Can Influence Continual Change in an Ecosystem?

Climate

• Rainfall, temperature, altitude and many other climatic elements determine the nature of an ecosystem. When any of these elements are altered, there is a resulting fluctuation, whether subtle or drastic, in the ecosystem. In the early 21st century, the increasing global temperatures that are part of the phenomenon of climate change are an example of this transformation. Many temperature-sensitive species of plants and animals are migrating northward as their habitats warm. Decreasing levels of rainfall drive water-loving species out of some areas, while increasing water levels introduce new habitats to others.

Food Sources

• The availability of food is the primary determining element in the viability of an ecosystem. For plants, this means the presence of soil, water and sunlight, while for climax carnivores, it means the presence of adequate populations of game species. Ecological history is filled with examples of ecosystems being radically altered when one or another food source is removed. The link populations of rabbits and foxes in many areas is an example of this dynamic. Fox populations are dependent on rabbit populations, which fluctuate naturally over the years. When rabbit populations crash, fox populations crash in quick succession.

Human Activity

• The activity of humans has been a major factor in the change and degradation of many ecosystems around the world. Human beings transform diverse ecosystems into monoculture environments, such as tree farms and industrial agriculture. They also pave over large areas and fill in wetlands for human use. All of these activities displace or destroy the many species that were previously using these areas. In the short term, it may appear that these ecosystems have been permanently transformed into exclusively human environments. However, in the long term, ecological change continues, and areas that are currently dominated by human beings will eventually return to a more diverse condition.

Disruptions

• Natural disruptions accelerate change within ecosystems through catastrophic events, such as earthquakes, volcanic eruptions, tidal waves and plagues. The short-term results of these events are often massive loss of life and biodiversity. In the long term, natural catastrophes open up areas of opportunity for the colonization of new ecological niches. Disrupted ecosystems exhibit some of the most rapidly changing natural developments, in contrast to climax of ecosystems, which change much more slowly.