Five Facts About a Land Ecosystem

An ecosystem, the web of interrelationships and dependencies that make up a natural habitat, is an extremely complex system. Several ways to evaluate or study an ecosystem exist, and many things can be said about an individual ecosystem, particularly in the case of land ecosystems that, because of man's primary settlement on land, have been more extensively studied than marine biomes.

Biodiversity

• Every ecosystem, including land ecosystems, has a quantifiable level of biodiversity. Biodiversity refers to the number of different species found in a single habitat and can be lower or higher depending on the amount of resources in the habitat, the level of biological competition and the number of particular niches to be filled. In the case of land ecosystems, tropical rain forests are among the most diverse whereas tundra has relatively low levels of biodiversity. As part of a larger natural system that links the whole planet, local biodiversity in any amount plays a critical role in maintaining species alive and supporting the evolutionary resilience of life on Earth.

Biomass

• Whereas biodiversity refers to the number of different species present in a habitat, biomass refers to the total mass of living organisms present in a habitat. An ecosystem, for instance, can have a very small number of species but huge numbers of each, yielding a low value of biodiversity but a very large value for biomass--basically the amount of living mass present in an ecosystem. As with biodiversity, every land ecosystem can be said to have a specific amount of biomass.

Hydrology

• Hydrology is the study of distribution, cyclical movement and quality of water. In land ecosystems, hydrology is a critical consideration for the configuration of the ecosystem. All living organisms need some amount of water to survive so that the configuration, abundance or scarcity of water in an ecosystem is a critical variable to consider when analyzing the functioning of the ecosystem. As the definition of an ecosystem requires that it be inhabited by living organisms and all living organisms need water to complete their life cycles, all ecosystems can be said to have a specific hydrological configuration.

Abiotic Factors

• In addition to the many biotic (or, living) factors that make up and shape a land ecosystem, a number of abiotic (i.e., non-living) variables profoundly impact the functioning of a system. Abiotic factors such as chemical elements, temperature and atmospheric conditions can determine the basic living conditions in a land ecosystem. The acidity of the soil, for instance, might favor the growth of trees with a high tolerance for acidic conditions in a pine forest, which in turn determines the kinds of animal life present based on the kinds of animals that can feed on food sources created by the presence of pines. The state of abiotic factors in an ecosystem is a critical fact that determines much of what happens in an ecosystem.

Carrying Capacity

• Every ecosystem also has a certain carrying capacity, a measure of the ecosystem's capacity to return to normal conditions after a disruption. Populations of a certain plant or animal, for instance, can fall somewhat due to a change in conditions but rebound as soon as the conditions return to normal. Of course, beyond a certain point, an ecosystem might be unable to return to its equilibrium point. Species driven to the brink of extinction are seldom able to recover to normal population levels without an extreme situation or intervention. Thus, this carrying capacity value is also a critical fact to be studied in the process of understanding an ecosystem.