Spatial and Temporal Benthic Diversity Patterns

Dear Colleagues,

Understanding the constraints on community composition at multiple spatial and temporal scales is an immense challenge to community and ecosystem ecologists. Indeed, spatial and temporal patterning of populations provide the means by which biodiversity is maintained in ecological communities.

Benthic communities can play an important role in aquatic ecosystem functioning. In particular, benthic macroinvertebrates are the major players in the transferral of energy to upper trophic levels, and include species with different life cycles and specific tolerances to stress events, which make them suitable to reflect the magnitude of disturbances. However, benthic condition assessments have to take into account that benthic communities show high spatial heterogeneity and temporal variations that are related to the influence of natural gradients of different factors contributing to the overall distribution of species, seasonal and interannual environmental changes, seasonal reproduction period, short life span, and temporal variability in the physical disturbance.

Ecological monitoring evaluates whether anthropogenic-induced changes in aquatic ecosystems affect the benthic diversity (e.g., community structure and composition, and species richness) and the biological properties of the system. However, a paucity of studies investigate natural variability at a hierarchy of spatial/temporal scales. Many patterns observed in benthic diversity are frequently interpreted in the light of such large scale processes, even though many small scale variations of benthic environments are responsible for complex patterns of benthic patchiness that can potentially confound the interpretation of results of the survey. Studing spatial and temporal patterning of benthic diversity across scales may yield important clues as to which scales of environmental heterogeneity influence community structure. In this context, the need for long term data is essential, given the large-scale environmental changes in aquatic ecosystems.

Understanding the pattern of changes in benthic diversity through community monitoring is therefore crucial in both management and environmental policy.

Dr. Cristina Munari
Guest Editor