Wind-Induced Changes in Zooplankton Diversity in a Temperate Sandy Beach Surf Zone: A preliminary methodology using Neutral red staining

Zooplankton responds quickly to environmental changes due to its sensitivity to hydrodynamic variations. This study investigates the impact of different wind events on zooplankton communities in the surf zone of a temperate sandy beach. Zooplankton samples were collected before and after each wind event from May 2017 to July 2019 at Pehuen Co sandy beach. High-frequency wind speed data were used to categorize wind events by direction and duration. Physical and biological variables were analyzed using general Linear Models (LMs) and Generalized Linear Models (GLMs). Additionally, the samples were stained with neutral red to distinguish living organisms from dead ones. The study found that wind direction and duration significantly affect the zooplankton community. Short-duration wind events led to an increase in zooplankton abundance, with Acartia tonsa and Paracalanus parvus being predominant. Winds from the west were associated with the presence of inner continental shelf species such as Ctenocalanus vanus and Euterpina acutifrons, and to a lesser extent, Calanoides carinatus and Labidocera fluviatilis, along with typical surf zone copepods. In contrast, long-duration wind events significantly decreased zooplankton abundance, with SE–SW winds linked to adventitious taxa. In all the samples analyzed before/after the storms, mortality varied from 100% to 4% dead organisms after storms, with the highest mortality generally observed after short-duration wind events. Wind events, particularly their direction and duration, play a crucial role in shaping the abundance and composition of zooplankton in the surf zone of temperate sandy beaches. These findings highlight the importance of considering wind patterns in managing and conserving marine biodiversity. This research contributes to our understanding of how abiotic factors like wind influence coastal ecosystems. The results affect biodiversity conservation strategies in marine environments due to climate change.