Ecological Zones

An ecological zone is a landscape unit that unites certain interrelated animal and plant communities (biocenosis) with a particular social formation and environmental conditions as part of an integrated system. The definition of an ecological [Page 844]zone relies on flexible criteria. However, humidity and altitude are key factors in terrestrial systems, while salinity and depth are key factors for maritime and continental water environments. Temperature is one of the common elements that affect these environments. All these factors, together with territorial configuration, hydrologic regime, organic matter, mineral content, and isotopic composition of soil or water, define ecological zones and their buffer areas.

The notion of ecological zones can be associated with other landscape ecology concepts, such as ecotope, biome, and niche. An ecotope is a pure land unit of the lowest rank that is associated with a uniform or homogeneous landscape. On the other hand, niche is the species’ or population's specialized role and function in an ecosystem and biome. Last, a biome is a land unit characterized by similar climatic and geographic conditions that correlates with specific plants and animal communities. Often biomes are defined by the characteristics of the most popular plants (e.g., trees define forests, grasses define grasslands). All these concepts follow the criteria of a hierarchical classification of landscape units.

An ecological zone has a broader geographic scope or scale than does an ecotope as it is not necessarily defined by a homogeneous landscape. On the other hand, unlike biomes, ecological zones take into account not only the living communities but also their geographical setting. Last, an ecological zone has a regional scale, making it a much broader concept than an ecological niche. Hence, an ecological zone is based on the concept of a whole functioning system from a historical perspective, giving less importance to biotic or abiotic factors alone. As the categories above note, an ecological zone becomes an important part of the landscape ecology terminology.