English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

Field studies on a variety of organisms have suggested that environmental variability plays a major role in determining spatial patterns in distribution and species diversity of estuanne organisms due to the effect of abiotic fluctuations on the physiology of animals. However, there is no study examining the effect of environmental variability on zooplankton distribution and diversity in estuaries. As vertical m~gration is obligatory behavior for the retention of planktonic animals at intermediate positions in the St. Lawrence Estuary (Canada), vertical stratification of the water column is considered the major source of environmental variability for zooplankton in this system. To evaluate the importance of this source of variability as a factor controlling the distribution and diversity of zooplankton in the estuary, we examined the relative contribution of each of the environmental factors of salinity, temperature, turbidity and vertical stratification in explaining spatial patterns of summer zooplankton distribution and diversity. Multivariate analyses revealed the presence of a longitudinal succession of seasonally stable species assemblages (tidal freshwater, true-estuarine and euryhalinemarine assemblages) whose spatial distribution was mainly a function of salinity and vertical stratification. Turbidity and temperature played a minor role in explaining spatial distribution. For all sampling periods, the limit between the true-estuarine and euryhaline-marine assemblages, the lowest number of population centers and the lowest zooplankton abundance all corresponded to the most vertically stratified waters. In contrast, population centers of all species were concentrated in the most abiotically stable parts of the estuary. We conclude that environmental variability is a major factor determining zooplankton distribution and diversity in the estuary. The spatio-temporal stability of the species assemblages and the seasonal variabihty in the abundance of some species also suggest that trophic interactions may play an important role in the regulation of zooplankton populations in the estuary.

Environmental variability as a factor controlling spatial patterns in distribution and species diversity of zooplankton in the St. Lawrence Estuary