Impact of Fisheries on Marine Ecosystems

Abstract

Marine Ecology: An ecosystemic view of anthropogenic impacts is a synthesis of the current knowledge about the structure and functioning of marine ecosystems, and their responses to the main anthropogenic impacts they are subjected to. Each chapter is spearheaded by experts in their respective fields, and contains much of the results of their own research on the subject, which has given a hands-on approach to each of them. In this book, the reader will find information of the major challenges of the Anthropocene, posed by humanity’s current lifestyle, to the biota of the planet, a point of view from specifically vulnerable ecosystems, and a section outlining the tools that humankind has developed to mitigate the damage to, protect, and even restore the marine biodiversity. It is the hope of the editors and authors of this book that the perspectives outlined here will help future generations with the increasingly difficult task of ensuring that the wonderful diversity of life does not vanish.The first section of the book addresses man-made challenges imposed to ecosystems from the optic of the challenge itself. These challenges are discussed in the light of recent research, and are accompanied by specific results produced by each group of experts on the subject. The major impacts on the biota are outlined, and mitigation strategies are discussed. Climate change, one of the major overarching phenomena, is discussed in the first chapter. Chapter 2 discusses the direct and indirect effects that fisheries at different scales have produced on the marine ecosystems that sustain them. In chapter 3 the authors explore the issues of large-scale aquaculture, and the sustainability of small-scale alternatives. Chemical contamination is a major threat to marine life, and different aspects of this challenge are treated in chapter 4. The section closes up with chapter 5, dedicated to sea littering and the patterns of its dispersal based on recent findings.The second section is dedicated to particular ecosystems, their major biological components and interactions, and how human impacts disrupt the natural dynamics that occur in them. The first three chapters in this section provide a detailed description of sandy beaches, rocky shores and estuarine environments. The chapters discuss environmental complexity and nuances of each marine habitat, the threats they are faced with, and strategies crucial to ensuring the long-term health and preservation of the biodiversity that they host. The section closes in chapter 9, which is dedicated to deep sea ecology, a vast, once-thought barren, ecosystem, that is nothing of the sort.The last section discusses tools and strategies to tackle these aforementioned issues. In order to understand, predict and restore the effects of natural or anthropogenic factors on the structure and function of ecosystems, it is essential to possess knowledge on the species inhabiting a particular environment. In this sense, accurate taxonomic identification of biological species is the first step. The chapter 10 analyzes current molecular techniques as a tool, complementary to phenotypic description, for the correct identification of known species and the discovery of cryptic biodiversity. Physiology links the individual with its environment in a mechanistic fashion. How organisms respond physiologically to fluctuating environmental conditions, and what tools has science developed to answer that question is discussed in chapter 11. We humans are inexorably intertwined with the health of marine environments. Given the unprecedented level of marine ecosystems degradation, governance of these environments must effectively ensure a sustainable and equitable use of it. This topic is developed and exemplified in chapter 12 of the book, which advocates the adoption of a holistic view of marine ecosystems, emphasizing their complex and dynamic nature. The last chapter of this book looks at how we can revert the damage and degradation inflicted upon the marine ecosystems discussed throughout the previous chapters. The initiatives and strategies to restore damaged environments are discussed and explored in this final chapter.