Marine biodiversity and ecosystem function: empirical approaches and future research needs

Abstract

cipated future influence of anthropogenic forcing (Sala et al. 2000). In response to such anxiety, an unprecedented increase in research over the last decade or so has explicitly examined the proposition that a reduction in biodiversity will cause a decrease in the provision of ecosystem-level processes (reviewed in Hooper et al. 2005). The establishment of this line of inquiry is credited to the proceedings of a seminal conference that sought to formalize, for the first time, the association between biodiversity and ecosystem function (Schulze & Mooney 1993). Understanding the mechanisms that underpin this presumed causal relationship has since become one of the primary research goals in ecology (Hooper et al. 2005).Following the emergence of a novel paradigm, the road towards a new consensus is supported by a parallel progression of observational, experimental and theoretical evidence. These are the primary axes along which fundamental ecological principles are derived and, providing that the conclusions drawn from these alternative approaches merge, are the means by which inferences about cause-effect relationships can be validated. In the biodiversity-ecosystem function arena (hereafter BEF) the mainstay of research to date has almost exclusively been weighted towards ecological experimentation in terrestrial plant systems, although there have been a small number of notable contributions on the marine environment (e.g. compare citations in Hooper et al. 2005). Curiously, correlational evidence or anecdotal observations in support of BEF relationships are seldom cited on their own, or alongside new findings, and are generally viewed with skepticism, despite overwhelming support for the notion that biological diversity regulates ecosystem processes (Schläpfer et al. 1999). Yet the use of experimental systems is not without issue, nor do they provide a scientific panacea in the context of BEF related research. Experimental data generated from simple synthetic model communities in highly controlled systems (mesocosms) have been routinely criticized on many levels (for summary, see Mooney 2002).Whether or not the same mechanistic processes identified from synthetic laboratory experiments are equally valid and transferable to the real world (terrestrial and/or marine) remains an open question. Historical and cultural differences between specialists within ecology (Raffaelli et al. 2005) have meant that the marine community has often lagged behind their terrestrial counterparts; the BEF process has been no exception. Aquatic ecologists were less enthusiastic and initially failed to see the significance of BEF research, despite direct appeals for participation and the publication of methodologies that demonstrate how marine ecology could contribute to the BEF dialogue . One of the most significant barriers to interspecialist cohesion within the BEF community related to the treatment of biodiversity as an explanatory variable, rather than as the response variable, as had been common practice (e.g. Flint & Kalke 20...

Characterizing the marine Natura 2000 network for the Atlantic region

“…Current knowledge is probably insufficient to determine exactly which species are key to maintaining the structure and function of different habitat types. Investigations of the importance of species to marine ecosystem structure and function are relatively uncommon and hampered by issues of scale (Solan et al, 2006). It is not easy to judge a priori which species are most important to the assemblage associated with a particular habitat.…”

What Is Marine Biodiversity? Towards Common Concepts and Their Implications for Assessing Biodiversity Status

“…The functional aspect is represented by the relationships among and between these marine organisms and the environments they inhabit, and is defined in terms of rates of ecological processes (Strong et al, 2015); most notably they include physiological processes, predator-prey relationships, trophic webs, competition, and resource partitioning. These functions vary on both temporal and spatial scales (Solan et al, 2006), and include some of the most important ecosystem services, including oxygen provisioning, CO 2 sequestration, and re-mineralization of nutrients (Duarte and Cebrian, 1996;Costanza et al, 1997;van den Belt and Costanza, 2012). Both structural and functional elements contributing to biodiversity play a fundamental role in maintaining and defining healthy marine systems (Selig et al, 2013).…”

Eutrophication and Hypoxia Diminish Ecosystem Functions of Benthic Communities in a New England Estuary

“…Much theoretical, empirical, and experimental research has been done in the past two decades on the relationship between biodiversity and ecosystem functioning. Results reveal complexity but show a strong positive relationship (e.g., Waldbusser et al, 2004;Balvanera et al, 2006;Solan et al, 2006;Worm et al, 2006;Goulletquer et al, 2014).…”

“…Consequences of hypoxic areas of Narragansett Bay holding half as many species as normoxic areas are numerous, including impaired capacity to provide food and maintain water quality (Solan et al, 2006;Worm et al, 2006). Major changes in estuarine functions result when benthic species losses lead to a reduction in the types of food available to predators; removal of large bioturbators that rework sediments; loss of suspension-feeding bivalves that clear bottom water; changes in reef or mat habitat; or collapse of facilitative or mutualistic interactions (CENR, 2010;Goulletquer et al, 2014).…”