All organisms are interconnected with each other and cannot live in complete isolation. There are close relationships between microorganisms, fungi, plants, and animals living in the same area. The entire biosphere of the earth consists of groups, which are called communities. In this topic, we will talk about how such communities live and how they are studied in science.
What is a community and its characteristics?
A community, or biocenosis, is the total amount of species living in the same area. Any community is formed historically, under the influence of a large number of factors – the properties of the environment, various external events, geographical changes, and so on. Stable relations develop between all participants in the biocenosis (for example, predator-prey, competitive relations, parasitism, and so on). Relationships in communities not always are tied to nutrition – after all, species can give each other protection, building materials, and assistance in reproduction. Biocenosis self-regulates and is a kind of closed environment that maintains its viability.
A community, strictly speaking, can be called almost anything – for example, a forest near the house is a large natural community inhabited by trees, insects, mammals, fungi, and so on. Your aquarium in the living room is also a community: after all, fish (sometimes of different species), algae, crustaceans, and so on, live together in it – but this is an example of an artificial community, but this community did not appear by itself but was created by human hands.
Characteristics of a community
The community has several main characteristics, but the most important are stability, growth form, and structure.
Stability is an important characteristic of a community. Community life depends on stability and self-regulation. Artificial communities often cannot exist on their own – fish in aquariums need to be fed, and the aquarium itself needs to be cleaned. This community is unstable, it will not survive without human help. Stable communities can exist for thousands of years. When describing communities, it is also important to take into account periodicity – regular waves of biological processes, that is, growth, reproduction, and so on.
The growth form and structure of the community are also important for diversity – this is how many life forms and what life forms there are in the community. Imagine a forest – in a "good" stable forest there are different types of plants, for example, trees, shrubs, and grasses.
Community as an object of research
Since the entire biosphere of the Earth consists of thousands of thousands of communities, the work of ecologists is reduced to the study of these communities. Biocenoses are one of the most important objects of research for environmental scientists. It doesn't matter at all what task scientists set for themselves – restoring a lost community, creating a new one somewhere where it never existed, or disrupting a community by introducing something new into it (making a highway through a forest) – all this requires accurate and careful study of communities, their characteristics.
Direct and indirect links between different types of communities are also studied separately. This helps scientists to develop community conservation measures, as well as to better understand how artificial communities can be created.
Finally, the study of communities allows a better study of the species and the individual organism. Since nothing lives in total solitude, every organism is constantly influenced by the environment, landscape, and other species.
Ecologists use several metrics to describe communities, the most important of which are biodiversity metrics.
Biodiversity is a measure of the complexity of a community, the totality of all species living together. At the same time, several "types" of biodiversity are distinguished:
1. Alpha diversity – the diversity of species within the same community,
2. Beta diversity – diversity between different communities,
3. Gamma diversity – the overall diversity of species in a landscape.
Community stability depends on biodiversity. The more species within the community, the more connections it has, and the more stable it is, since it is more difficult to break all the chains. In addition, the more species, the better and more rationally the environment is used since the species regulate each other and mutually use each other. If the community consists of only a few species, then it is usually enough to remove one – and the community will fall apart.
Conclusion
A community or biocenosis is a collection of all species that historically inhabit the same territory and have formed a complex system of relationships. One of the most important aspects of a community is biodiversity. Community is important to study because species influence each other and this influence is critical for each individual species or organism.