Metacommunity theory highlights the potential of β-diversity as a useful link to empirical resear... more Metacommunity theory highlights the potential of β-diversity as a useful link to empirical research, especially in diverse systems where species exhibit a range of stage-dependent dispersal characteristics. To investigate the importance of different components and scales of β-diversity in community assembly, we conducted a large-scale disturbance experiment and compared relative recovery across multiple sites and among plots within sites on the rocky shore. Six sites were spread along 80 km of coastline and, at each site, five plots were established, matching disturbed and undisturbed quadrats. Recovery was not complete at any of the sites after 1 year for either epibenthos (mostly composed of macroalgae and, locally, mussels) or infauna. Significant differences in recovery among sites were observed for epibenthos but not for infauna, suggesting that different community assembly processes were operating. This was supported by epibenthos in the recovering plots having higher species turnover than in undisturbed sediment, and recovery well predicted by local diversity, while infaunal recovery was strongly influenced by the epibenthic community's habitat complexity. However, infaunal community recovery did not simply track formation of habitat by recovering epibenthos, but appeared to be overlain by within-site and among-site aspects of infaunal β-diversity. These results suggest that documenting changes in the large plants and animals alone will be a poor surrogate for rocky shore community assembly processes. No role for ecological connectivity (negative effect of among-site β-diversity) in driving recovery was observed, suggesting a low risk of effects from multiple disturbances propagating along the coast, but a limited resilience at the site scale to large-scale disturbances such as landslides or oil spills.
Page 212. THE PROBLEM OF SCALE: UNCERTAINTIES AND IMPLICATIONS FOR SOFT-BOTTOM MARINE COMMUNITIES... more Page 212. THE PROBLEM OF SCALE: UNCERTAINTIES AND IMPLICATIONS FOR SOFT-BOTTOM MARINE COMMUNITIES AND THE ASSESSMENT OF HUMAN IMPACTS SIMON F. THRUSH, SARAH M. LAWRIE, JUDI E ...
This chapter describes various aspects of how we can define ecosystem function and situations eco... more This chapter describes various aspects of how we can define ecosystem function and situations ecosystem function in a continuum from ecosystem processes to services. Illustrating that functions are about connections, the chapter uses examples of productivity, organic matter decomposition, ecosystem metabolism, habitat creation and foodwebs. Changes in the contributions of function to ecosystem dynamics are considered. Sedimentary ecosystems are multifunctional, requiring the development of new methods to assess this aspect of sediments and trait-based approaches are discussed. The role of ecosystem functions in underpinning ecosystem services is described to ensure that valuation and mapping exercises do not lose sight of the foundational role of ecosystem functions.
... habitat heterogeneity on beta diversity demonstrated here suggests that small-scale habitat h... more ... habitat heterogeneity on beta diversity demonstrated here suggests that small-scale habitat heterogeneity ... Effects of seagrass landscape structure, structural complexity and hydrodynamic regime on ... Landscape ecology and the marine environment: how spatial configuration of ...
This chapter highlights the questions to ask of data collection methods and statistical analyses ... more This chapter highlights the questions to ask of data collection methods and statistical analyses before you plunge into their use. It discusses data collection methods within the context of study design, focussing on the resolution and size (in area or time) that methods collect over. The methods covered are those that help explain patterns and processes produced by plants and animals interacting with the sediment and the water column. Similarly, statistical analyses that increase the interpretation of data and allow understanding of interacting processes are highlighted. The need to balance information, replication and costs associated with statistical power is also discussed. As this chapter provides a brief overview only on subjects that have been the subjects of entire books, it also contains references to more extensive coverage.
This chapter introduces the range of biological and physical processes that disturb soft sediment... more This chapter introduces the range of biological and physical processes that disturb soft sediment. It introduces the concept of disturbance regimes that connect the extent, frequency and magnitude of disturbance. Post-disturbance recovery processes are described in terms of processes that occur within the disturbed patch and processes that influence recovery from outside the patch. Moving on from the patch scale, the chapter introduces the concept of patch dynamics and the concept of the seafloor as a mosaic of patches at different stages of recovery from disturbance. Connectivity between patches is a critical factor linking local recovery processes to landscape-scale processes. This mosaic perspective leads to the introduction of metacommunity dynamics and the potential for heterogeneous landscapes to fragment and eventually homogenise seafloor communities as a consequence of the loss of large habitat-defining species.
Suspension-feeding bivalves play an important role in coastal ecosystems by affecting near-bed hy... more Suspension-feeding bivalves play an important role in coastal ecosystems by affecting near-bed hydrodynamics and, subsequently, rates of biodeposition. We designed a high-resolution field study to investigate rates of sedimentation and biodeposition around ...
This chapter looks at the links between biodiversity and ecosystem function in soft sediments to ... more This chapter looks at the links between biodiversity and ecosystem function in soft sediments to help understand the implications of biodiversity loss on ecosystem services. The chapter contains a focus on the challenges in developing real-world tests of biodiversity–ecosystem function (BEF) relationships. The various forms of BEF relationships, their implications and the different elements of biodiversity that link to function are described. Given the multiple functions that occur in soft-sediment ecosystems, this has important implications for the assessment and implications of BEF relationships and functional performance in the up-scaling of BEF relationships. The role of BEF in underpinning many ecosystem services and the interconnections in biodiversity and ecosystem service relationships close out the chapter.
This chapter addresses the biological processes that influence community composition and dynamics... more This chapter addresses the biological processes that influence community composition and dynamics, highlighting the multi-trophic and multi-functional nature of soft-sediment communities. Characterising the biological interactions into competition, predation, adult–juvenile interaction, facilitation, parasitism and disease, the chapter initially focusses on what we know about these processes, their effect on other biological components and their importance in different benthic habitats. It then extends to consider how they, in conjunction with mobility of species, can influence the broader-scale spatial structure and temporal dynamics connecting communities and functions. The chapter recognises the importance of differences in strength of interaction and the potential for weak interactions to affect community dynamics. This is framed around the concept of self-organisation as an emergent characteristic of ecosystem interaction networks and how meta-communities may be constructed.
This chapter introduces the roles of sediment properties and hydrodynamic conditions in influenci... more This chapter introduces the roles of sediment properties and hydrodynamic conditions in influencing soft-sediment communities. It identifies environmental factors that are commonly used to characterise soft-sediment habitats and used to tease out the role of habitat variation from other factors that influence populations and communities. The differences between cohesive and non-cohesive sediments that profoundly influence ecosystem functions are described. Hydrodynamics particularly at the sediment–water interface are introduced as a critical factor affecting many ecosystem processes. The chapter introduces the differences in laminar and turbulent flows. Coastal soft sediments in particular are places of high organic matter remineralisation and thus critical for the recycling of primary nutrients and primary production, particularly by microphytobenthos. These factors underpin the important role of marine sediments in biogeochemistry and earth system processes.
This chapter explores the interactions of plants and animals with their immediate sedimentary env... more This chapter explores the interactions of plants and animals with their immediate sedimentary environment. Plants and animals fundamentally change the physical and chemical characteristics of their sedimentary environment. The changes they effect are dependent on their size, living position, feeding mode and mobility. The types of changes are discussed as well as the resultant ability of plants and animals to actually create seafloor habitats and contribute to sediment heterogeneity at both small and large scales. Seafloor habitats are therefore best defined by a mix of physical and biology rather than physical descriptors alone. But the differences between how different animals feed and move and their ability to create structures such as tubes and burrows that influence the flows of oxygen and porewater within the sediments and across the sediment–water interface mean that there are not only a variety of vegetated seafloor habitats but a variety of non-vegetated ones.
Metacommunity theory highlights the potential of β-diversity as a useful link to empirical resear... more Metacommunity theory highlights the potential of β-diversity as a useful link to empirical research, especially in diverse systems where species exhibit a range of stage-dependent dispersal characteristics. To investigate the importance of different components and scales of β-diversity in community assembly, we conducted a large-scale disturbance experiment and compared relative recovery across multiple sites and among plots within sites on the rocky shore. Six sites were spread along 80 km of coastline and, at each site, five plots were established, matching disturbed and undisturbed quadrats. Recovery was not complete at any of the sites after 1 year for either epibenthos (mostly composed of macroalgae and, locally, mussels) or infauna. Significant differences in recovery among sites were observed for epibenthos but not for infauna, suggesting that different community assembly processes were operating. This was supported by epibenthos in the recovering plots having higher species turnover than in undisturbed sediment, and recovery well predicted by local diversity, while infaunal recovery was strongly influenced by the epibenthic community's habitat complexity. However, infaunal community recovery did not simply track formation of habitat by recovering epibenthos, but appeared to be overlain by within-site and among-site aspects of infaunal β-diversity. These results suggest that documenting changes in the large plants and animals alone will be a poor surrogate for rocky shore community assembly processes. No role for ecological connectivity (negative effect of among-site β-diversity) in driving recovery was observed, suggesting a low risk of effects from multiple disturbances propagating along the coast, but a limited resilience at the site scale to large-scale disturbances such as landslides or oil spills.
Page 212. THE PROBLEM OF SCALE: UNCERTAINTIES AND IMPLICATIONS FOR SOFT-BOTTOM MARINE COMMUNITIES... more Page 212. THE PROBLEM OF SCALE: UNCERTAINTIES AND IMPLICATIONS FOR SOFT-BOTTOM MARINE COMMUNITIES AND THE ASSESSMENT OF HUMAN IMPACTS SIMON F. THRUSH, SARAH M. LAWRIE, JUDI E ...
This chapter describes various aspects of how we can define ecosystem function and situations eco... more This chapter describes various aspects of how we can define ecosystem function and situations ecosystem function in a continuum from ecosystem processes to services. Illustrating that functions are about connections, the chapter uses examples of productivity, organic matter decomposition, ecosystem metabolism, habitat creation and foodwebs. Changes in the contributions of function to ecosystem dynamics are considered. Sedimentary ecosystems are multifunctional, requiring the development of new methods to assess this aspect of sediments and trait-based approaches are discussed. The role of ecosystem functions in underpinning ecosystem services is described to ensure that valuation and mapping exercises do not lose sight of the foundational role of ecosystem functions.
... habitat heterogeneity on beta diversity demonstrated here suggests that small-scale habitat h... more ... habitat heterogeneity on beta diversity demonstrated here suggests that small-scale habitat heterogeneity ... Effects of seagrass landscape structure, structural complexity and hydrodynamic regime on ... Landscape ecology and the marine environment: how spatial configuration of ...
This chapter highlights the questions to ask of data collection methods and statistical analyses ... more This chapter highlights the questions to ask of data collection methods and statistical analyses before you plunge into their use. It discusses data collection methods within the context of study design, focussing on the resolution and size (in area or time) that methods collect over. The methods covered are those that help explain patterns and processes produced by plants and animals interacting with the sediment and the water column. Similarly, statistical analyses that increase the interpretation of data and allow understanding of interacting processes are highlighted. The need to balance information, replication and costs associated with statistical power is also discussed. As this chapter provides a brief overview only on subjects that have been the subjects of entire books, it also contains references to more extensive coverage.
This chapter introduces the range of biological and physical processes that disturb soft sediment... more This chapter introduces the range of biological and physical processes that disturb soft sediment. It introduces the concept of disturbance regimes that connect the extent, frequency and magnitude of disturbance. Post-disturbance recovery processes are described in terms of processes that occur within the disturbed patch and processes that influence recovery from outside the patch. Moving on from the patch scale, the chapter introduces the concept of patch dynamics and the concept of the seafloor as a mosaic of patches at different stages of recovery from disturbance. Connectivity between patches is a critical factor linking local recovery processes to landscape-scale processes. This mosaic perspective leads to the introduction of metacommunity dynamics and the potential for heterogeneous landscapes to fragment and eventually homogenise seafloor communities as a consequence of the loss of large habitat-defining species.
Suspension-feeding bivalves play an important role in coastal ecosystems by affecting near-bed hy... more Suspension-feeding bivalves play an important role in coastal ecosystems by affecting near-bed hydrodynamics and, subsequently, rates of biodeposition. We designed a high-resolution field study to investigate rates of sedimentation and biodeposition around ...
This chapter looks at the links between biodiversity and ecosystem function in soft sediments to ... more This chapter looks at the links between biodiversity and ecosystem function in soft sediments to help understand the implications of biodiversity loss on ecosystem services. The chapter contains a focus on the challenges in developing real-world tests of biodiversity–ecosystem function (BEF) relationships. The various forms of BEF relationships, their implications and the different elements of biodiversity that link to function are described. Given the multiple functions that occur in soft-sediment ecosystems, this has important implications for the assessment and implications of BEF relationships and functional performance in the up-scaling of BEF relationships. The role of BEF in underpinning many ecosystem services and the interconnections in biodiversity and ecosystem service relationships close out the chapter.
This chapter addresses the biological processes that influence community composition and dynamics... more This chapter addresses the biological processes that influence community composition and dynamics, highlighting the multi-trophic and multi-functional nature of soft-sediment communities. Characterising the biological interactions into competition, predation, adult–juvenile interaction, facilitation, parasitism and disease, the chapter initially focusses on what we know about these processes, their effect on other biological components and their importance in different benthic habitats. It then extends to consider how they, in conjunction with mobility of species, can influence the broader-scale spatial structure and temporal dynamics connecting communities and functions. The chapter recognises the importance of differences in strength of interaction and the potential for weak interactions to affect community dynamics. This is framed around the concept of self-organisation as an emergent characteristic of ecosystem interaction networks and how meta-communities may be constructed.
This chapter introduces the roles of sediment properties and hydrodynamic conditions in influenci... more This chapter introduces the roles of sediment properties and hydrodynamic conditions in influencing soft-sediment communities. It identifies environmental factors that are commonly used to characterise soft-sediment habitats and used to tease out the role of habitat variation from other factors that influence populations and communities. The differences between cohesive and non-cohesive sediments that profoundly influence ecosystem functions are described. Hydrodynamics particularly at the sediment–water interface are introduced as a critical factor affecting many ecosystem processes. The chapter introduces the differences in laminar and turbulent flows. Coastal soft sediments in particular are places of high organic matter remineralisation and thus critical for the recycling of primary nutrients and primary production, particularly by microphytobenthos. These factors underpin the important role of marine sediments in biogeochemistry and earth system processes.
This chapter explores the interactions of plants and animals with their immediate sedimentary env... more This chapter explores the interactions of plants and animals with their immediate sedimentary environment. Plants and animals fundamentally change the physical and chemical characteristics of their sedimentary environment. The changes they effect are dependent on their size, living position, feeding mode and mobility. The types of changes are discussed as well as the resultant ability of plants and animals to actually create seafloor habitats and contribute to sediment heterogeneity at both small and large scales. Seafloor habitats are therefore best defined by a mix of physical and biology rather than physical descriptors alone. But the differences between how different animals feed and move and their ability to create structures such as tubes and burrows that influence the flows of oxygen and porewater within the sediments and across the sediment–water interface mean that there are not only a variety of vegetated seafloor habitats but a variety of non-vegetated ones.
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