Marine habitat classification for ecosystem-based management: A proposed hierarchical framework

Creating a habitat classification and mapping system for marine and coastal ecosystems is a daunting challenge due to the complex array of habitats that shift on various spatial and temporal scales. To meet this challenge, several countries have, or are developing, national classification systems and mapping protocols for marine habitats. To be effectively applied by scientists and managers it is essential that classification systems be comprehensive and incorporate pertinent physical, geological, biological, and anthropogenic habitat characteristics. Current systems tend to provide over-simplified conceptual structures that do not capture biological habitat complexity, marginalize anthropogenic features, and remain largely untested at finer scales. We propose a multi-scale hierarchical framework with a particular focus on finer scale habitat classification levels and conceptual schematics to guide habitat studies and management decisions. A case study using published data is included to compare the proposed framework with existing schemes. The example demonstrates how the proposed framework\u27s inclusion of user-defined variables, a combined top-down and bottom-up approach, and multi-scale hierarchical organization can facilitate examination of marine habitats and inform management decisions. © 2010 Springer Science+Business Media, LLC

Variability of Symbiodinium Communities in Waters, Sediments, and Corals of Thermally Distinct Reef Pools in American Samoa.

Reef-building corals host assemblages of symbiotic algae (Symbiodinium spp.) whose diversity and abundance may fluctuate under different conditions, potentially facilitating acclimatization to environmental change. The composition of free-living Symbiodinium in reef waters and sediments may also be environmentally labile and may influence symbiotic assemblages by mediating supply and dispersal. The magnitude and spatial scales of environmental influence over Symbiodinium composition in different reef habitat compartments are, however, not well understood. We used pyrosequencing to compare Symbiodinium in sediments, water, and ten coral species between two backreef pools in American Samoa with contrasting thermal environments. We found distinct compartmental assemblages of clades A, C, D, F, and/or G Symbiodinium types, with strong differences between pools in water, sediments, and two coral species. In the pool with higher and more variable temperatures, abundance of various clade A and C types differed compared to the other pool, while abundance of D types was lower in sediments but higher in water and in Pavona venosa, revealing an altered habitat distribution and potential linkages among compartments. The lack of between-pool effects in other coral species was due to either low overall variability (in the case of Porites) or high within-pool variability. Symbiodinium communities in water and sediment also showed within-pool structure, indicating that environmental influences may operate over multiple, small spatial scales. This work suggests that Symbiodinium composition is highly labile in reef waters, sediments, and some corals, but the underlying drivers and functional consequences of this plasticity require further testing with high spatial resolution biological and environmental sampling

Data from: Variability of Symbiodinium communities in waters, sediments, and corals of thermally distinct reef pools in American Samoa

Reef-building corals host assemblages of symbiotic algae (Symbiodinium spp.) whose diversity and abundance may fluctuate under different conditions, potentially facilitating acclimatization to environmental change. The composition of free-living Symbiodinium in reef waters and sediments may also be environmentally labile and may influence symbiotic assemblages by mediating supply and dispersal. The magnitude and spatial scales of environmental influence over Symbiodinium composition in different reef habitat compartments are, however, not well understood. We used pyrosequencing to compare Symbiodinium in sediments, water, and ten coral species between two backreef pools in American Samoa with contrasting thermal environments. We found distinct compartmental assemblages of clades A, C, D, F, and/or G Symbiodinium types, with strong differences between pools in water, sediments, and two coral species. In the pool with higher and more variable temperatures, abundance of various clade A and C types differed compared to the other pool, while abundance of D types was lower in sediments but higher in water and in Pavona venosa, revealing an altered habitat distribution and potential linkages among compartments. The lack of between-pool effects in other coral species was due to either low overall variability (in the case of Porites) or high within-pool variability. Symbiodinium communities in water and sediment also showed within-pool structure, indicating that environmental influences may operate over multiple, small spatial scales. This work suggests that Symbiodinium composition is highly labile in reef waters, sediments, and some corals, but the underlying drivers and functional consequences of this plasticity require further testing with high spatial resolution biological and environmental sampling

Cunning_PLoSONE_Dryad_Archive

This archive file contains all data and scripts necessary to reproduce the analyses and figures presented in this manuscript

A Video Seafloor Survey of Epibenthic Communities in the Pacific Arctic including Distributed Biological Observatory Stations in the Northern Bering and Chukchi Seas

Two separate efforts to characterize epibenthic communities in the northern Bering and Chukchi seas using video imagery from a drop camera system have now been completed. In the initial phase in 2008, we acquired video imagery from the USCGC Healy while drifting on station during the multidisciplinary Bering Sea Program and used cluster analysis and non-metric multidimensional scaling to identify epibenthic assemblage types and associated sediment characteristics based upon along-track epifaunal counts. We also quantified the areal density of easily recognizable organisms such as brittle stars (Ophiura sp.) and sea stars, which were abundant and easily identified. While sampling was not extensive enough to rigorously compare the density of epifauna with trawling data available from prior years, our observations confirmed the characteristics of epifaunal communities sampled through much more labor-intensive trawling. Densities of epifauna that could be readily enumerated were of the same order of magnitude in both types of observations. During the second phase in 2016 and 2017 of video observations from the CCGS Sir Wilfrid Laurier, we improved the quality of imagery, and obtained seafloor video footage from each station in the internationally coordinated sampling grid in the Distributed Biological Observatory (DBO). This grid lies in the productive waters of the northern Bering and Chukchi seas. Quantitative analysis was not undertaken in this second phase, but the imagery confirms the presence of specific organismal community assemblages that can be related to environmental factors such as sediment grain size and water mass identity that are available from other project data collected during the Bering Sea and DBO projects. For example, sandier sediments typically had diverse epifaunal communities including filter feeders as significant community components. In muddier sediments, deposit feeders such as brittle stars predominated. All the second phase video footage has been posted in both abbreviated form on the video-sharing website youtube.com, and longer (10 min per station) versions are freely downloadable from a Google Drive server. Future videography may help identify changes in epibenthic diversity and community composition and could be successfully evaluated with crowd-sourced citizen science and/or more traditional scientific documentation

Differentiation of <i>Symbiodinium</i> communities between pools.

<p>NMDS biplots on Bray-Curtis dissimilarities are shown for water (A), sediment (B), and coral (C). Samples from pool 300 and pool 400 are represented by circles and triangles, respectively. Taxa are plotted in the same ordination space and colored by clade (A = green, C = yellow, D = purple, F = red, G = orange) to show their role in driving the differentiation between samples (e.g., clade D in association with sediment samples from pool 400). Three sediment samples are plotted with arrows indicating they lie outside the plot range. For corals, 90% confidence ellipses surround groups of species categorized qualitatively as low (< 0.4), intermediate (0.4–0.6), or high (> 0.6) overall dissimilarity (<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0145099#pone.0145099.t001" target="_blank">Table 1</a>) to illustrate the range of observed variability in different coral species. Coral species whose symbiont communities were significantly different between pools (<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0145099#pone.0145099.t001" target="_blank">Table 1</a>) are represented by filled symbols (gray = <i>Psammacora contigua</i>, black = <i>Pavona venosa</i>).</p

<i>Symbiodinium</i> clade composition for complete dataset.

<p>Bars represent the proportion of sequences in each sample from each clade.</p

Altered compartmental distributions of <i>Symbiodinium</i> between pools.

<p>The inner ring shows <i>Symbiodinium</i> taxa (clade A = green, C = yellow, D = purple, F = red, G = orange) that were differentially abundant in each compartment (middle ring: water = blue, sediment = gray, coral = pink, <i>Pavona venosa</i> = Pv, <i>Psammocora contigua</i> = Pc) between pools. The outer ring indicates whether taxa were more or less abundant in each pool, and ribbons connect instances where taxa were differentially abundant in multiple compartments. Ribbons reveal different compartmental distributions of taxa in each pool: in pool 300 (vs. 400), 8 taxa (including 4 clade D) were less abundant in sediments and more abundant in water and/or coral, while 2 other clade C taxa were more abundant in sediments and less abundant in water.</p

Location and <i>Symbiodinium</i> clade composition of water, coral, and sediment samples in each pool.

<p>Points represent sample positions and pie charts represent clade composition (A = green, C = yellow, D = purple, F = red, G = orange). Water samples (A) showed more clade A near shore, while sediments (C) showed more clade A further from shore, and clusters of more similar communities (e.g., clades D and F in the northeast and clade G in the southwest corners of pool 300; similar mixtures of C, D, and A in northwest corner of pool 400). Corals (B) tended to have more clade D near pool edges, especially in pool 400. Clade composition for <i>Porites</i> spp. (i.e., species with the lowest dissimilarity, <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0145099#pone.0145099.t001" target="_blank">Table 1</a>) is not shown here, but can be seen in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0145099#pone.0145099.g001" target="_blank">Fig 1</a>. While data are visualized at the clade level, spatial autocorrelation tests reflect patterns in total diversity.</p

Evidence of rapid functional benthic recovery following the Deepwater Horizon oil spill

The 2010 Deepwater Horizon incident was a massive deep-sea oil spill and resulted in deposition of hydrocarbons at the seafloor surface. Soft sediment benthic macrofauna provide critical global ecosystem services, and little is known about their recovery trajectories from similar disturbances in the deep sea. Recent publications report an initial opportunistic benthic infaunal response and predict 50-100 years for recovery of species-level diversity, abundance, and composition. Sediment profile and plan view imaging data collected at depths from 1040 to 1689 m in 2011 and 2014 not only confirm this opportunistic response but also indicate further stages of functional benthic recovery. The recovery trajectory mimicked benthic succession following organic enrichment that is widely recorded in coastal systems but not the deep sea. Bioturbating taxa were present deep in the sediment column in both years. In 2014, a decline in the relative abundance of opportunistic taxa and a positive rebound in the apparent redox potential discontinuity depth, an integrated measure of biogeochemical functioning, were recorded. These results suggest that bioturbation-mediated microbial degradation is a plausible mechanism by which rapid functional benthic recovery occurred. With oil and gas extraction prevalent in the deep sea, improving the understanding of benthic recovery in these environments is critical.</p