What do we mean by a community, for this section? Examples are:
Shortgrass prairie
Phragmites stand
Bottomland hardwoods
Shallow water lentic
Coastal bay bottom
Longleaf pine
Ephemeral stream
Communities can also be defined by a focus on the animals present, e.g., bottom-dwelling fish, neotropical migrants, aquatic mammals, or pollinators.
A community is defined as a system of plants and animals living together and linked by their interactions with each other and with their environment. This is important to ecosystem restoration and protection because one way to look at an ecosystem is to view it as a system of communities, defined as above, and characterized by a complex of ecological processes. The two constructs, communities and ecosystems, can be considered as a hierarchy, as shown in the diagram below.
The nomenclature of communities does not have the rigor that nomenclature of species has achieved. Instead, designation of a community is largely in the eyes of the beholder. The National Vegetation Classification System level of Community Association corresponds to what is usually visualized as a community. The existing vegetation is described to species, and has repeatable patterns and "typical" woody and herbaceous vegetation.
Other words that are often used to describe communities include cover class, cover type, ecological type, ecosystem, habitat type, substrate class, timber stand, vegetation class, and vegetation type. Statistical techniques exist to use data to define similar groups and therefore derive communities, e.g., ordination. However, the naming is still not standard.