An ecosystem or biome describes a unique environment and each living organism (biotic) and non-living factor (abiotic) that is contained in it or that characterizes it. An ecosystem embodies all aspects of a single habitat, including all interactions between its different elements.
The content of an ecosystem can vary from light and humidity levels to plant and animal life. The processes of a biome vary from birth and reproduction to death and composition.
In an ecosystem, living organisms are grouped into producers, consumers, and decomposers, the former represents all plant life, consumers the organisms that eat them and each other, and the latter those scavengers and bacteria that decompose organic matter dead. Together, these living components are known as biotic factors. Abiotic factors, or the nonliving components of an ecosystem, can be climatic, social, and edaphic (influenced by soil or soil type).
The heat flow or flow of energy that travels through the food chain of an ecosystem is initially provided through the input of the ecosystem itself, for example, the amount of sunlight available to plant life and the levels of nutrients ground. Without abiotic factors, no ecosystem can provide biotic factors.
Ecosystems are constantly changing. Human threats to biodiversity include deforestation, pollution, disease transmission across natural borders, the introduction of non-indigenous species, and the reduction of natural habitats through overpopulation. The most natural threats include migration of a species to a particular region, a change of season, or a deadly disease that affects only one species.
The examples of ecosystems are limitless. An ecosystem does not have to cover a large region. They exist in small ponds, within human homes, and even in the human intestine. Alternatively, ecosystems can cover large areas of the planet.
One of the smallest ecosystems (in area, not population) is the human intestine. This ecosystem does not receive energy from sunlight, but it supports millions of living organisms. These are supplied with a food source in a humid, dark, and warm environment, perfect conditions for these microorganisms. Our bodies contain thousands of ecosystems, all of them supporting huge colonies of healthy single-celled organisms, but also pathogens.
A small shady pond in a temperate region represents an aquatic ecosystem. Soil with excess water and excess shade affect the biodiversity of plant life, where only the species suitable for this environment will proliferate. Producer availability affects which organisms thrive in and around the pond. Primary consumers (herbivores) must provide enough energy for secondary consumers, and so on. If pesticides are added to the pond, or if the pond is frozen or choked with thick layers of grass, the ecosystem of this pond must adapt.
On a much larger, but artificial scale, the Eden biome, a smaller representation of the global ecosystem, contains multiple ecosystems for research purposes, where separate domes have varying climates and light levels, and support different producers, consumers, and decomposers. In an artificial biome, many variables are tightly controlled. An elephant herd is not usually placed in an artificial biome.
Types of Ecosystem
Ecosystem types abound; however, the most basic categorization involves three habitats: terrestrial, marine, and aquatic. Naturally, these groups can be divided into thousands of smaller systems, each of which offers a different combination of climate, habitat, and life forms.
At approximately 57,268,900 square miles, the terrestrial ecosystem covers only 29% of the globe. As these habitats are varied, terrestrial ecosystems are divided into six types.
The deciduous forest ecosystem is found in temperate regions and experiences fluctuations in temperature and precipitation according to four seasons. Current conservation goals include reintroducing apex predators after slaughter practices from previous centuries and providing an environment full of mature trees to offset unregulated deforestation.
Desert ecosystems can be hot and dry, semi-arid, coastal or cold. The characteristic that unites them is the lack of water and the absence of a layer of soil in which larger vegetation, such as shrubs and trees, can thrive. Although indigenous life has adapted to the absence of water, a desert still cannot support populations in a wetter habitat. Large herbivores cannot survive in a desert environment in large numbers, and this in turn limits the number of larger omnivores and carnivores.
The prairies are also known as prairies, pampas, savannas, or steppes. They can be tropical or temperate and are a link between the desert and the forest. They rarely get enough rain to support the trees, but they have enough soil nutrients to feed large tracts of grass. This provides considerable energy for primary consumers. With a large producer population, a grassland ecosystem can similarly support large herds of herbivores, which in turn feed consumers higher up the food chain hierarchy.
Taiga is a subarctic forest region south of the Arctic Circle. It has layers of permafrost or rock below the shallow soil, making the soil swampy. The taiga supports a large number of conifers: slow-growing and cold-resistant trees. Other plant life is small and includes lichens, swamp plants, and small shrubs. The following map shows how this ecosystem is distributed throughout the world.
Rainforests are probably the most frequently cited ecosystems in the field of environmental conservation. Located around the equator, constant rain and heat coupled with the lack of seasons provide a stable climate, however, the clouds and the canopy of the trees make the rainforest floor a dark place. The soil is leached with nutrients through constant precipitation. Plantlife has adapted and is abundant, turning the rain forest ecosystem into the terrestrial ecosystem with the greatest biodiversity.
The tundra, the last of the six terrestrial biomes, is the treeless environment of the Arctic Circle. Climate change is rapidly changing this ecosystem, as the warmer climate brings in non-indigenous predators, where they compete for limited prey. Certain shrubs are taking root as the arctic permafrost layer melts. These compete with lichen, the caribou’s main food source.
Marine ecosystems –
Marine and aquatic ecosystems cover 139,668,500 square miles; 97% of this is saltwater, making marine ecosystems the largest biome category.
Large marine ecosystems (SMLs) are particularly difficult to observe and control, as different saltwater habitats have complex chemical compositions that vary from coast to coast and from shallow to deep. These compositions change forever due to tides and currents. Pollutants and organisms travel in courses that, while predictable, are continually on the move. The large volume of water that covers a large marine ecosystem is immense. The following map shows the population trends of native and invasive jellyfish species and their populations. This study looks at trends in jellyfish behavior on an LME. It is possible to predict this trend on a global scale, but the potential and actual variables are innumerable.
Marine or ocean ecosystems are grouped into open marine systems, ocean floors, coral reefs, estuaries, saltwater wetland estuaries, and mangroves. These cover marine environments from the deepest ocean surfaces and floors to partially terrestrial tidal marshes.
Aquatic ecosystems –
Freshwater ecosystems cover approximately 3% of the planet’s surface. Aquatic ecosystems also include estuaries before freshwater meets salt, wetlands, ponds (natural or artificial), lakes, and rivers.
As freshwater is essential for all life, aquatic biomes are extremely important. However, they are very small compared to other habitats and have been used as landfills for centuries. National Geographic reports that freshwater species are between four and six times more at risk of extinction than terrestrial or marine species. Freshwater biomes and coastal marine systems are also at high risk of eutrophication, a natural process that takes centuries to develop. Eutrophication is caused by higher sediment levels which in turn increase nutrient levels and stimulate excessive plant growth. When vegetation becomes extinct, after depleting additional nutrients or becoming victims of its own success, its decomposition leads to dead zones or hypoxic zones.
Any anatomical system contains microbiota: bacteria, fungi, archaea and mutualistic, commensal, pathogenic or parasitic viruses.
Health publications now report a relationship between intestinal biodiversity and the health of other anatomical and physiological systems, such as mood, hormone production, and endurance. This can be compared to the effect of reducing biodiversity in aquatic ecosystems, and the effect this will have on populations in distant locations. For example, research is investigating the prevalence of chronic inflammatory diseases as microbial diversity in the gut decreases.
The microbiome may not be an ecological ecosystem, but it is a complete ecosystem of living and non-living components in a habitat where interactions take place and which has its own climate.
Ecosystem Definition, Types, Example and Explained