Diversity Patterns of Benthic Macrofauna Caused by Marine Fish Farming

Carlos Sanz-Lázaro,Arnaldo Marín

doi:10.3390/d3020176

Abstract

This paper reviews the patterns observed in the diversity and structure of the macrofauna benthic community under the influence of fish farming. First, we explain the effects of organic enrichment on the sediment and the consequences for the inhabiting communities. We describe the diversity trends in spatial and temporal gradients affected by fish farming and compare them with those described by the Pearson and Rosenberg model. We found that in general terms, the trends of diversity and other community parameters followed the Pearson and Rosenberg model but they can vary to some extent due to sediment local characteristics or to secondary disturbances. We also show the different mechanisms by which wild fish can affect macrofauna diversity patterns under fish farming influence. In addition, we comment the importance of the macrofauna diversity in the ecosystem functions and propose some guidelines to measure functional diversity related to relevant processes at ecosystem level. We propose more research efforts in the main topics commented in this review to improve management strategies to guarantee a good status of the diversity and ecosystem functioning of sediments influenced by fish farming.

Highlights

Marine fish farming has experienced an almost exponential growth over recent decades and, worldwide, is the fastest growing food production system [1]
Under the influence of fish farming, macrofauna follows the general trends of diversity and other community parameters defined in the P-R model, but these trends can vary according to sediment local characteristics
Macrofauna diversity patterns under the influence of fish farming have been studied to some extent, but further research is needed in order to have a more accurate forecasting capacity of these patterns

Summary

Introduction

Marine fish farming has experienced an almost exponential growth over recent decades and, worldwide, is the fastest growing food production system [1]. These processes produce an increase in the supply of oxygen and other electron acceptors of the seabed surface with the porewater This increases the metabolic capacity of bacteria and, in turn, of the sediment, to mineralize OM [29,30] and recycle nutrients [31] (Figure 1). The spatial and temporal patterns of macrofauna diversity under conditions of organic enrichment has been widely documented in the Pearson and Rosenberg model ([44]; P-R model), a seminal and still highly relevant definition of spatial organic enrichment gradient This successional model describes a reversible continuum of faunal change from an un-perturbed species rich community to a perturbed species poor one [45]. We explain the importance of the macrofauna diversity in the ecosystem functioning and we give some recommendations to assess functional diversity related to relevant processes at ecosystem level

Spatial Patterns in Benthic Macrofauna Diversity Caused by Fish Farming

Temporal Patterns in Benthic Macrofauna Diversity after Fish Farm Abatement

Findings

Conclusions