Sedimentary dynamics and benthic macrofauna distribution: Insights from the shoreface in southern Portugal

Hydrodynamic Conditions Effects on Soft-Bottom Subtidal Nearshore Benthic Community Structure and Distribution

“…Estuarine inputs, as a source of suspended particulate matter, and wave exposure, by inducing sediment remobilization, influenced in opposite directions the grain-size distribution and the organic matter contents of sediments [28]. As confirmed by this study, this natural sediment mobility due to hydrodynamic conditions is a factor of importance on nearshore so -bottom, controlling the spatial distribution of many species [21,97,101] by causing both press-and pulse-types of disturbance as defined by Harris [32].…”

“…in Portuguese Continental shelf [17,28] and in South Brittany [11]. Hydrodynamic conditions, broadly defined as the duration of wave-induced sediment remobilization, were also the most relevant factor, explaining the highest percentage of spatial variation in the macrofauna along the southeastern Portuguese coast [28].…”

“…Recent previous studies carried out along the Atlantic coast showed similar degree of variation explained by environmental variables. Along the subtidal coastal fringe of South Brittany, Dutertre et al [11] found a 51% correlation with a combination of 16 natural abiotic factors whereas Carvalho et al [28], Veiga et al [58] and Martins et al [17] showed which can be manifested as changes in abundance, diversity and fitness of individuals and communities [86]. Identifying and integrating the effects of natural pressures is an essential challenge for understanding and managing coastal biotic resources [87,88] particularly when they are subjected to anthropogenic threats.…”

“…Identifying and integrating the effects of natural pressures is an essential challenge for understanding and managing coastal biotic resources [87,88] particularly when they are subjected to anthropogenic threats. In shallow subtidal, previous studies have focused on analysing patterns of macrobenthic assemblages along salinity or depth gradients [28,60,62,89]. is study is novel in that it characterizes the benthic macrofauna distribution patterns across three nearshore so -bottom sites, located at the same depth (6 m) and exposed to different hydrodynamic conditions, along the French Basque coast.…”

“…ese natural physical disturbances impact the structure of macrobenthic communities and also their functional responses to important ecosystem processes, such as resource usage (nutrients recycling), feeding interactions (trophic structure), habitat building organisms (ecosystem engineering, biogenic structures), bioaccumulation (body size, growth rate, longevity) and sediment properties (tube-building, burrowing activities) [24][25][26][27][28]. erefore, hydrodynamic conditions, as natural physical disturbances, determine the colonization of a given habitat [22], they alter interactions between individuals [29] and consequently shape macrobenthic community [21,23,28,30,31].…”