Ecosystem. Ecosystem structure, concept and types
Just as people live in houses and apartments,so in nature there are separate from other systems. They are separate and, one might say, independent. They are called ecosystems and include many different organisms. In addition, they obey certain laws. In this article we will consider what are ecosystems: concept, structure, purpose. And also tell you what's in them.
The concept of
The totality of organisms living together ina certain habitat and interacting with each other in one way or another, is denoted by the term "ecosystem". This concept was proposed in 1935 by the English scientist A. Tensli. He studied the interrelations of organisms and their joint development. By the way, he is considered one of the founders of such a science as ecology, which deals with the study of what an ecosystem is. The ecosystem structure is represented by two main components: a biocenosis and a biotope. Under the first, the organisms and their interrelations are understood, and under the second - the habitat. As a rule, the whole set of living beings participates in the ecosystem: from bacteria to higher animals. And what is surprising, the whole community is in balance, which, breaking, is restored again, and each of its members performs extremely important functions.
Biogeocenosis
The totality of some components,exchanging energy and capable of a more or less autonomous existence, is an ecosystem. The ecosystem structure assumes the presence of all the main organisms: bacteria, plants, animals, fungi. But some of them may be absent. In this situation, it makes sense to separate this concept from biogeocenosis. This term implies a community in which there are all of the above components. Moreover, the biotic structure of the ecosystem can include only one participant, for example, only bacteria. This situation can be observed in communities formed, for example, on the basis of animal corpses. Thus, the ecosystem and biogeocenosis are not synonyms, because the latter is a broader concept. Despite this, they are often confused.
Classification and structuring
In addition to the fact that scientists share someecosystem criteria among themselves, they are also interested in their internal arrangement. Different approaches and points of view in total give a fairly complete picture, which allows us to consider each element separately. It is not surprising that in structuring there are used so many criteria: the type of food and functions, the species belonging, the location of the participants. Of course, it is worth considering the most important of the factors in more detail, because the ecological structure of the ecosystem without talking, for example, about its composition, makes little sense.
As for the division of communities among themselves,as a rule, the main criterion is the prevailing environment. Another important feature is the naturalness of its origin and the ability to autonomously maintain functioning. Here we are talking first of all about interference in the nature of the human factor, which also makes sense to be indicated in more detail, but later.
By function
The trophic structure of the ecosystem delineatesparticipating in it organisms by type of food. According to the cycle of substances in nature, nothing is taken from the void and can not simply disappear. Obviously, it's just how the various matter transforms. And here two opposite groups of organisms come into play: autotrophs and heterotrophs. The latter are animals and mushrooms that consume organic matter. The first (plants and bacteria) come exactly the opposite. By the way, they in turn are divided into photosynthetic and chemosynthetic drugs.
The functional structure of the ecosystem assumesthe same division, but under different names. Here we are talking about producers, decomposers, consumers and destructors. Two of these approaches are closely related to the concept of food chains.
By hierarchy
Naturally, any system of this complexityis divided into several levels. The first and most comprehensive is the already mentioned biocenosis, which is the totality of all participating living organisms. Further, the hierarchical structure of ecosystems assumes a division into phyto-, zoo-, myco- and microbenocenosis. Each of these separate groups contains a population, called a population. Finally, the smallest unit is an individual (or individual), which is a separate specimen.
There is also a functional hierarchy. The trophic structure of the ecosystem, as already mentioned, implies a division into producers, consumers, decomposers and destructors. But here there are several levels. So, it all starts with green plants that receive mineral substances and water from the soil, as well as sunlight. Herbivores already belong to the consumers of the first level and consume greens for food. In turn, they serve as a food for predators standing a step higher. So even here you can see your own special hierarchy.
By species
Even within a single type of organism canthere is a certain diversity, and this is not surprising. The species structure of the ecosystem is an important indicator of the correlation of certain plants, animals, fungi, microorganisms, etc. This characteristic depends on a large number of factors: geographical position, climatic zone, water regime, age of the community. Similar species can be observed in thousands of kilometers from each other, if the main indicators in them are similar. In addition to the very existence of certain organisms, their number is also important. The most common representatives of wildlife in this or that ecosystem are called environmental generators and, accordingly, perform key functions and create conditions for the survival of other species.
However, this does not mean that smallparticipants are not too important. On the contrary, in a number of cases a particular biotic structure of ecosystems can provide very accurate information about its state. The presence of rare specimens of plants and animals may allow us to understand, for example, how pure water and air are.
On a spatial basis
At first glance, the division of ecosystems associated withtheir location is quite obvious. Steppe, forest, desert, tundra, seabed - a set of organisms living here, without doubt, will be completely different. But such a classification is appropriate only if it is a question of comparing several systems and the differences between them.
On the other hand, each individual communitywill have its own physical hierarchy. The spatial structure of the ecosystem in the forest, for example, is easily visible, it is divided into several levels. Nightingales build nests on higher trees, and wagtails prefer to stay closer to the ground. And among the vegetation inequality is obvious: trees, shrubs, grass and moss are located on completely different levels. Scientists collect these characteristics called longline, or floor.
Terrestrial ecosystem
The structure of the ecosystem, located on land,can be very different, but almost always very interesting. They are everywhere: in forests, steppes, deserts, high in the mountains, and each of them is curious in its own way. All of them are united by a land-air habitat. Meanwhile, the differences in them may be even greater than the total. For example, the structure of the forest ecosystem in the tropics will be quite unlike what is observed in the middle zone of Russia. Moreover, the green massif in South America will be strikingly different from the picture in South-West Asia. As already mentioned, the climatic belt is one of the main, but not the only factor that influences how the ecosystem is formed. The structure of the ecosystem is too complex and multidimensional, and therefore delicious and mysterious.
Water
Freshwater and marine organisms, algae,plankton, jellyfish, deep-sea fish - the species structure of the ecosystem located in the world's oceans is no less entertaining than the terrestrial one. Often it can be even more complicated. The structure of the aquatic ecosystem in some ways may resemble the terrestrial one, for example, there is also tieredness here. But there is a very important difference. It consists in the fact that the pyramid of biomass is turned upside down. This means that the primary producers (here it is a diverse plankton) are much more numerous and reproduce faster than consumers or consumers. First of all, this applies to the sea and ocean depths, but in the freshwater communities the same situation can be observed. The most interesting thing is that the structure of the aquatic ecosystem includes both one of the smallest organisms and the largest ones. And they all live peacefully in the neighborhood with each other.
Value
The importance of ecosystems is difficult to overestimate. First, they are all interconnected by the cycle of substances in nature. Elements from one system fall into another, so that they are also interdependent. Secondly, they allow more or less to preserve biodiversity - each community of organisms in its own way is unique, surprising and beautiful. Finally, all the natural resources that a person receives without thinking - clean water, agricultural land, fertile soil, fresh air - gives him or her an ecosystem. The structure of the ecosystem, like the entire biosphere, is quite fragile, so do not forget about its role and sometimes you should think about what the planet is worth to save its wealth for descendants.
Anthropogenic factor
Man by his activities one way or anotheraffects almost all ecosystems. But if influence on some of them is mediated, then others experience it directly. Deforestation, pollution of air, soil and water, catching fish and animals - all this becomes a serious test for maintaining the natural balance.
By the way, people continue to learn how to modelstable ecosystems on their own, and also try to manage existing ones. As a rule, the life cycle of artificially created communities is not too great, and stability raises a lot of questions. Nevertheless, it would be very useful to learn how to manage ecosystems, because in this way it would be possible to achieve greater productivity of agriculture, and also try to restore the destroyed. Unfortunately, as long as human influence on nature is assessed extremely negatively, because its actions cause a lot of consequences, in particular:
- reduction of biological diversity;
- climate change due to a shift in the gas composition of the atmosphere;
- reduction of forest areas;
- change and destruction of unique communities and conditions;
- depletion of natural resources;
- desertification and erosion of soils;
- accumulation of domestic garbage and pollution of the environment;
- change in the structure of ecosystems;
- thinning of the ozone layer.
It is worth thinking about the consumer attitudehumanity to the planet and to reflect on whether it is possible to preserve nature in its magnificent variety. After all, it is not so difficult to destroy, but will it be possible to create?
