All living organisms live on Earth not in isolation from each other, but in the form of communities. In them, everything is interconnected, both living organisms and factors of inanimate nature. Such a formation in nature is called an ecosystem that lives according to its own specific laws and has specific signs and qualities that we will try to get to know.
Ecosystem concept
Studying any ecosystem thoroughly is quite difficult, since it includes a huge number of living organisms, as well as abiotic factors.
There is such a science as ecology, which deals with the study of the relationship between living nature and nonliving. But these relations can only be carried out within the framework of a certain ecosystem and do not occur spontaneously and randomly, but according to some laws.
The types of ecosystems are different, but they all represent a set of living organisms that interact with each other and with the environment through the exchange of substances, energy and information. That is why the ecosystem remains stable and sustainable for a long period of time.
Ecosystem classification
Despite the great diversity of ecosystems, they are all open, without which their existence would not have been possible. The types of ecosystems are different, and the classification may be different. If we keep in mind the origin, then ecosystems are:
Natural or natural. In them, all interaction is carried out without the direct participation of man. They, in turn, are divided into:
- Ecosystems that are completely dependent on solar energy.
- Systems that receive energy from both the sun and other sources.
2. Artificial ecosystems. Created by human hands, and can exist only with his participation. They are also divided into:
- Agroecosystems, that is, those associated with human economic activity.
- Techno-ecosystems appear in connection with the industrial activity of people.
- Urban ecosystems.
Another classification distinguishes the following types of natural ecosystems:
1. Ground:
- Rainforests.
- Desert with grassy and shrubby vegetation.
- Savannah.
- Steppes.
- Deciduous forest.
- Tundra.
2. Freshwater ecosystems:
- Standing ponds (lake, pond).
- Flowing waters (rivers, streams).
- Swamps.
3. Marine ecosystems:
- Ocean.
- Continental shelf.
- Fishing areas.
- Estuaries, bays.
- Deep water rift zones.
Regardless of the classification, you can see the diversity of ecosystem species, which is characterized by its set of life forms and numerical composition.
Distinctive features of the ecosystem
The concept of ecosystem can be attributed to both natural formations and artificially created by man. If we talk about natural, then they are characterized by the following symptoms:
- Mandatory elements in any ecosystem are living organisms and abiotic environmental factors.
- In any ecosystem, there is a closed cycle from the production of organic substances to their decomposition into inorganic components.
- The interaction of species in ecosystems provides sustainability and self-regulation.
The whole surrounding world is represented by various ecosystems, which are based on living matter with a certain structure.
Biotic ecosystem structure
Even if the ecosystems differ in species diversity, the abundance of living organisms, their life forms, but the biotic structure in any of them is still the same.
Any types of ecosystems include the same components, without their presence, the functioning of the system is simply impossible.
- The producers.
- Consumables of the first order.
- Consumables of the second order.
- Reducers.
The first group of organisms includes all plants that are capable of photosynthesis. They produce organic matter. Chemotrophs, which form organic compounds, belong to the same group. But only for this they do not use solar energy, but the energy of chemical compounds.
Consumers include all organisms that need to receive organic matter from outside to build their bodies. This includes all herbivorous organisms, predators and omnivores.
Reducers, which include bacteria, fungi, turn the remains of plants and animals into inorganic compounds suitable for use by living organisms.
Ecosystem functioning
The largest biological system is the biosphere; it, in turn, consists of individual components. You can compose the following chain: species-population - ecosystem. The smallest unit in ecosystems is the species. In each biogeocenosis, their number can vary from several tens to hundreds and thousands.
Regardless of the number of individuals and individual species in any ecosystem, there is a constant exchange of matter, energy, not only among themselves, but also with the environment.
If we talk about the exchange of energy, then it is quite possible to apply the laws of physics. The first law of thermodynamics states that energy does not disappear without a trace. It only turns from one species to another. According to the second law, in a closed system, energy can only increase.
If physical laws are applied to ecosystems, then we can conclude that they support their livelihoods due to the presence of solar energy, which organisms can not only capture, but also transform, use, and then give into the environment.
Energy is transferred from one trophic level to another; during the transfer, one type of energy is transformed into another. Part of it, of course, is lost in the form of heat.
Whatever types of natural ecosystems exist, such laws apply to absolutely everyone.
Ecosystem structure
If you look at any ecosystem, you can definitely see in it that various categories, such as producers, consumers and reducers, are always represented by a whole set of species. Nature envisages that if something suddenly happens to one of the species, then the ecosystem will not die from this; it can always be successfully replaced by another. This explains the sustainability of natural ecosystems.
A wide variety of species in the ecosystem, a variety of food chains ensure the sustainability of all processes that occur within the community.
In addition, any system has its own laws to which all living organisms obey. Based on this, several structures within the biogeocenosis can be distinguished:
- The species structure. Shows the ratio of plant and animal species. In each system, this indicator is different, it depends on many factors: geographical location, climate, age of the ecosystem. A species that is superior in number to all others is called a medium former. But small representatives in some cases are an indicator of well-being in the system.
- Trophic structure. The diversity of species, branched food chains in the ecosystem are an indicator of sustainability. In any biogeocenosis, organisms are interconnected primarily by nutritional ties. You can always make up the power circuit. Usually they begin with a plant organism, and end with a predator. For example, a grasshopper eats grass, a titmouse will eat it, and a kite will catch it.
- Spatial structure. The question arises how such a large number of different species coexists in one territory. All this is due to a certain structure, adhering to which species are dispersed. In the forest, the very first tier is occupied by photophilous trees. Some species of birds also nest here. The next level is the trees lower, and again the abode for some species of animals.
Any structure is necessarily present in any ecosystem, but it can vary significantly. For example, if we compare the biogeocenosis of the desert and the rainforest, the difference is visible to the naked eye.
Artificial ecosystems
Such systems are created by human hands. Despite the fact that all components of the biotic structure are mandatory in them, as in natural ones, there are still significant differences. Among them are the following:
- Agrocenoses are distinguished by poor species composition. Only those plants that people grow there grow. But nature takes its toll, and always, for example, in a field of wheat you can see cornflowers, daisies, various arthropods settle. In some systems, even birds manage to build a nest on the ground and raise chicks.
- If a person does not care for this ecosystem, then cultivated plants will not withstand competition with their wild relatives.
- Agrocenoses still exist due to the additional energy that a person brings, for example, fertilizing.
- Since the grown biomass of plants is withdrawn along with the crop, the soil is depleted in nutrients. Therefore, for further existence, again, the intervention of a person who will have to make fertilizers in order to grow the next crop is necessary.
It can be concluded that artificial ecosystems do not belong to stable and self-regulating systems. If a person ceases to care for them, they will not survive. Gradually, wild species will displace cultivated plants, and the agrocenosis will be destroyed.
For example, an artificial ecosystem of three species of organisms can easily be created at home. If you put an aquarium, pour water into it, put a few twigs of elodea and settle two fish, here you have the artificial system ready. Even such a simple one cannot exist without human intervention.
The value of ecosystems in nature
Speaking globally, all living organisms are distributed across ecosystems, so their importance can hardly be underestimated.
- All ecosystems are interconnected by a cycle of substances that can migrate from one system to another.
- Due to the presence of ecosystems in nature, biodiversity is preserved.
- All the resources that we draw from nature, give us precisely the ecosystem: clean water, air, fertile soil.
Any ecosystem is very easy to destroy, especially considering the capabilities of man.
