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Kosek K, Kukliński P. Impact of kelp forest on seawater chemistry - A review. MARINE POLLUTION BULLETIN 2023; 196:115655. [PMID: 37839130 DOI: 10.1016/j.marpolbul.2023.115655] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/26/2023] [Revised: 09/18/2023] [Accepted: 10/09/2023] [Indexed: 10/17/2023]
Abstract
Kelp forests, globally distributed in cool temperate and polar waters, are renowned for their pivotal role in supporting species diversity and fostering macroalgae productivity. These high-canopy algal ecosystems dynamically influence their surroundings, particularly by altering the physicochemical properties of seawater. This review article aims to underscore the significance of kelp forests in modifying water masses. By serving as effective carbon sinks through the absorption of bicarbonate (HCO3-) and carbon dioxide (CO2) for photosynthesis, kelp forests mitigate nearby acidity levels while enhancing dissolved oxygen concentrations, essential for sustaining diverse marine communities. Additionally, kelp beds have exhibited the need to use inorganic ions (NO3-, NO2-, PO43-) from seawater in order to grow, albeit with associated increases in NH4+ concentrations. Specific examples and findings from relevant studies will be presented to illustrate the profound impact of kelp forests on seawater chemistry, emphasizing their vital role in marine ecosystems.
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Affiliation(s)
- Klaudia Kosek
- Marine Ecology Department, Institute of Oceanology, Polish Academy of Sciences, Powstańców Warszawy 55, 81-712 Sopot, Poland.
| | - Piotr Kukliński
- Marine Ecology Department, Institute of Oceanology, Polish Academy of Sciences, Powstańców Warszawy 55, 81-712 Sopot, Poland
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2
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Pessarrodona A, Assis J, Filbee-Dexter K, Burrows MT, Gattuso JP, Duarte CM, Krause-Jensen D, Moore PJ, Smale DA, Wernberg T. Global seaweed productivity. SCIENCE ADVANCES 2022; 8:eabn2465. [PMID: 36103524 PMCID: PMC9473579 DOI: 10.1126/sciadv.abn2465] [Citation(s) in RCA: 25] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
The magnitude and distribution of net primary production (NPP) in the coastal ocean remains poorly constrained, particularly for shallow marine vegetation. Here, using a compilation of in situ annual NPP measurements across >400 sites in 72 geographic ecoregions, we provide global predictions of the productivity of seaweed habitats, which form the largest vegetated coastal biome on the planet. We find that seaweed NPP is strongly coupled to climatic variables, peaks at temperate latitudes, and is dominated by forests of large brown seaweeds. Seaweed forests exhibit exceptionally high per-area production rates (a global average of 656 and 1711 gC m-2 year-1 in the subtidal and intertidal, respectively), being up to 10 times higher than coastal phytoplankton in temperate and polar seas. Our results show that seaweed NPP is a strong driver of production in the coastal ocean and call for its integration in the oceanic carbon cycle, where it has traditionally been overlooked.
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Affiliation(s)
- Albert Pessarrodona
- UWA Oceans Institute and School of Biological Sciences, University of Western Australia, Crawley, WA 6009, Australia
- Corresponding author: ,
| | - Jorge Assis
- CCMAR, CIMAR, Universidade do Algarve, Gambelas, Faro, Portugal
| | - Karen Filbee-Dexter
- UWA Oceans Institute and School of Biological Sciences, University of Western Australia, Crawley, WA 6009, Australia
- Institute of Marine Research, His, Norway
| | | | - Jean-Pierre Gattuso
- CNRS, Laboratoire d’Océanographie de Villefranche, Sorbonne Université, 181 chemin du Lazaret, F-06230 Villefranche-sur-mer, France
- Institute for Sustainable Development and International Relations, Sciences Po, 27 rue Saint Guillaume, F-75007 Paris, France
| | - Carlos M. Duarte
- Red Sea Research Centre (RSRC) and Computational Bioscience Research Center (CBRC), King Abdullah University of Science and Technology, Thuwal 23955, Saudi Arabia
- Arctic Research Centre, Aarhus University, Aarhus C, Denmark
| | - Dorte Krause-Jensen
- Arctic Research Centre, Aarhus University, Aarhus C, Denmark
- Department of Ecoscience, Aarhus University, Vejlsøvej 25, DK-8600 Silkeborg, Denmark
| | - Pippa J. Moore
- The Dove Marine Laboratory, School of Natural and Environmental Science, Newcastle University, Newcastle upon Tyne NE1 7RU, UK
| | - Dan A. Smale
- Marine Biological Association of the United Kingdom, Citadel Hill, Plymouth PL1 2PB, UK
| | - Thomas Wernberg
- UWA Oceans Institute and School of Biological Sciences, University of Western Australia, Crawley, WA 6009, Australia
- Institute of Marine Research, His, Norway
- Roskilde University, Box 260, 4000 Roskilde, Denmark
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3
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Thyrring J, Peck LS. Global gradients in intertidal species richness and functional groups. eLife 2021; 10:64541. [PMID: 33739285 PMCID: PMC8032391 DOI: 10.7554/elife.64541] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2020] [Accepted: 03/18/2021] [Indexed: 11/13/2022] Open
Abstract
Whether global latitudinal diversity gradients exist in rocky intertidal α-diversity and across functional groups remains unknown. Using literature data from 433 intertidal sites, we investigated α-diversity patterns across 155° of latitude, and whether local-scale or global-scale structuring processes control α-diversity. We, furthermore, investigated how the relative composition of functional groups changes with latitude. α-Diversity differed among hemispheres with a mid-latitudinal peak in the north, and a non-significant unimodal pattern in the south, but there was no support for a tropical-to-polar decrease in α-diversity. Although global-scale drivers had no discernible effect, the local-scale drivers significantly affected α-diversity, and our results reveal that latitudinal diversity gradients are outweighed by local processes. In contrast to α-diversity patterns, species richness of three functional groups (predators, grazers, and suspension feeders) declined with latitude, coinciding with an inverse gradient in algae. Polar and tropical intertidal data were sparse, and more sampling is required to improve knowledge of marine biodiversity.
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Affiliation(s)
- Jakob Thyrring
- British Antarctic Survey, Cambridge, United Kingdom.,Department of Zoology, University of British Columbia, Vancouver, Canada.,Arctic Research Centre, Department of Bioscience, Aarhus University, Silkeborg, Denmark.,Homerton College, University of Cambridge, Cambridge, United Kingdom.,Marine Ecology, Department of Bioscience, Aarhus University, Silkeborg, Denmark
| | - Lloyd S Peck
- British Antarctic Survey, Cambridge, United Kingdom
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Ferreira JG, Arenas F, Martínez B, Hawkins SJ, Jenkins SR. Physiological response of fucoid algae to environmental stress: comparing range centre and southern populations. THE NEW PHYTOLOGIST 2014; 202:1157-1172. [PMID: 24580117 DOI: 10.1111/nph.12749] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/30/2013] [Accepted: 01/28/2014] [Indexed: 06/03/2023]
Abstract
Climate change has led to alterations in assemblage composition. Species of temperate macroalgae at their southern limits in the Iberian Peninsula have shown shifts in geographical range and a decline in abundance ultimately related to climate, but with the proximate factors largely unknown. We performed manipulative experiments to compare physiological responses of Fucus vesiculosus and Fucus spiralis from Portugal and Wales (UK), representing, respectively, southern and central areas of their distribution, to different intensities of solar radiation and different air temperatures. Following exposure to stressful emerged conditions, Portuguese and Welsh individuals of both fucoid species showed increased frond temperature, high desiccation levels and reduced photophysiological performance that was evident even after a 16 h recovery period, with light and temperature acting in an additive, not an interactive, manner. The level of physiological decline was influenced by geographical origin of populations and species identity, with algae from the south and those living higher on the shore coping better with stressful conditions. The negative effect of summer conditions on photophysiology may contribute to changes in fucoid abundance and distribution in southern Europe. Our results emphasise how physiological performance of geographically distinct populations can differ, which is particularly relevant when predicting responses to climate change.
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Affiliation(s)
- João G Ferreira
- School of Ocean Sciences, Bangor University, Menai Bridge, Anglesey, LL59 5AB, UK
| | - Francisco Arenas
- Laboratory of Coastal Biodiversity, Interdisciplinary Centre of Marine and Environmental Research (CIIMAR), University of Porto, Rua dos Bragas 289, 4050-123, Porto, Portugal
| | - Brezo Martínez
- Área de Biodiversidad y Conservación, Rey Juan Carlos University, 28933, Móstoles, Madrid, Spain
| | - Stephen J Hawkins
- School of Ocean Sciences, Bangor University, Menai Bridge, Anglesey, LL59 5AB, UK
- Ocean and Earth Science, National Oceanography Centre Southampton, University of Southampton, European Way, Southampton, SO14 3ZH, UK
| | - Stuart R Jenkins
- School of Ocean Sciences, Bangor University, Menai Bridge, Anglesey, LL59 5AB, UK
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Miloslavich P, Cruz-Motta JJ, Klein E, Iken K, Weinberger V, Konar B, Trott T, Pohle G, Bigatti G, Benedetti-Cecchi L, Shirayama Y, Mead A, Palomo G, Ortiz M, Gobin J, Sardi A, Díaz JM, Knowlton A, Wong M, Peralta AC. Large-scale spatial distribution patterns of gastropod assemblages in rocky shores. PLoS One 2013; 8:e71396. [PMID: 23967204 PMCID: PMC3742765 DOI: 10.1371/journal.pone.0071396] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2012] [Accepted: 06/28/2013] [Indexed: 11/19/2022] Open
Abstract
Gastropod assemblages from nearshore rocky habitats were studied over large spatial scales to (1) describe broad-scale patterns in assemblage composition, including patterns by feeding modes, (2) identify latitudinal pattern of biodiversity, i.e., richness and abundance of gastropods and/or regional hotspots, and (3) identify potential environmental and anthropogenic drivers of these assemblages. Gastropods were sampled from 45 sites distributed within 12 Large Marine Ecosystem regions (LME) following the NaGISA (Natural Geography in Shore Areas) standard protocol (www.nagisa.coml.org). A total of 393 gastropod taxa from 87 families were collected. Eight of these families (9.2%) appeared in four or more different LMEs. Among these, the Littorinidae was the most widely distributed (8 LMEs) followed by the Trochidae and the Columbellidae (6 LMEs). In all regions, assemblages were dominated by few species, the most diverse and abundant of which were herbivores. No latitudinal gradients were evident in relation to species richness or densities among sampling sites. Highest diversity was found in the Mediterranean and in the Gulf of Alaska, while highest densities were found at different latitudes and represented by few species within one genus (e.g. Afrolittorina in the Agulhas Current, Littorina in the Scotian Shelf, and Lacuna in the Gulf of Alaska). No significant correlation was found between species composition and environmental variables (r≤0.355, p>0.05). Contributing variables to this low correlation included invasive species, inorganic pollution, SST anomalies, and chlorophyll-a anomalies. Despite data limitations in this study which restrict conclusions in a global context, this work represents the first effort to sample gastropod biodiversity on rocky shores using a standardized protocol across a wide scale. Our results will generate more work to build global databases allowing for large-scale diversity comparisons of rocky intertidal assemblages.
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Affiliation(s)
- Patricia Miloslavich
- Departamento de Estudios Ambientales and Centro de Biodiversidad Marina, Universidad Simón Bolívar, Caracas, Miranda, Venezuela.
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6
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Krause-Jensen D, Marbà N, Olesen B, Sejr MK, Christensen PB, Rodrigues J, Renaud PE, Balsby TJS, Rysgaard S. Seasonal sea ice cover as principal driver of spatial and temporal variation in depth extension and annual production of kelp in Greenland. GLOBAL CHANGE BIOLOGY 2012; 18:2981-2994. [PMID: 28741817 PMCID: PMC3597251 DOI: 10.1111/j.1365-2486.2012.02765.x] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/31/2012] [Revised: 05/23/2012] [Accepted: 05/28/2012] [Indexed: 05/06/2023]
Abstract
We studied the depth distribution and production of kelp along the Greenland coast spanning Arctic to sub-Arctic conditions from 78 ºN to 64 ºN. This covers a wide range of sea ice conditions and water temperatures, with those presently realized in the south likely to move northwards in a warmer future. Kelp forests occurred along the entire latitudinal range, and their depth extension and production increased southwards presumably in response to longer annual ice-free periods and higher water temperature. The depth limit of 10% kelp cover was 9-14 m at the northernmost sites (77-78 ºN) with only 94-133 ice-free days per year, but extended to depths of 21-33 m further south (73 ºN-64 ºN) where >160 days per year were ice-free, and annual production of Saccharina longicruris and S. latissima, measured as the size of the annual blade, ranged up to sevenfold among sites. The duration of the open-water period, which integrates light and temperature conditions on an annual basis, was the best predictor (relative to summer water temperature) of kelp production along the latitude gradient, explaining up to 92% of the variation in depth extension and 80% of the variation in kelp production. In a decadal time series from a high Arctic site (74 ºN), inter-annual variation in sea ice cover also explained a major part (up to 47%) of the variation in kelp production. Both spatial and temporal data sets thereby support the prediction that northern kelps will play a larger role in the coastal marine ecosystem in a warmer future as the length of the open-water period increases. As kelps increase carbon-flow and habitat diversity, an expansion of kelp forests may exert cascading effects on the coastal Arctic ecosystem.
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Affiliation(s)
- Dorte Krause-Jensen
- Department of Bioscience, Aarhus UniversityVejlsøvej 25, DK-8600, Silkeborg, Denmark
| | - Núria Marbà
- Department of Global Change Research, IMEDEA (CSIC-UIB), Institut Mediterrani d'Estudis AvançatsMiquel Marquès 21, 07190, Esporles (Illes Balears), Spain
| | - Birgit Olesen
- Department of Bioscience, Aarhus UniversityVejlsøvej 25, DK-8600, Silkeborg, Denmark
- Department of Bioscience, Aarhus UniversityOle Worms Allé, Building 1135, DK-8000, Århus C, Denmark
| | - Mikael K Sejr
- Department of Bioscience, Aarhus UniversityVejlsøvej 25, DK-8600, Silkeborg, Denmark
| | | | - João Rodrigues
- Department of Applied Mathematics and Theoretical Physics, Centre for Mathematical SciencesWilberforce Road, Cambridge, CB3 0WA, United Kingdom
| | - Paul E Renaud
- Fram Centre for Climate and the Environment, Akvaplan-nivaN-9296, Tromsø, Norway
| | - Thorsten JS Balsby
- Department of Bioscience, Aarhus UniversityVejlsøvej 25, DK-8600, Silkeborg, Denmark
| | - Søren Rysgaard
- Greenland Climate Research Centre (Co. Greenland Institute of Natural Resources)Kivioq 2, Box 570, 3900, Nuuk, Greenland
- Centre for Earth Observation Science, CHR Faculty of Environment Earth and Resources, University of Manitoba499 Wallace Building, Winnipeg, MB R3T 2N2, Canada
- Arctic Research Center, Aarhus UniversityDK-8000, Århus C, Denmark
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7
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Mejia AY, Puncher GN, Engelen AH. Macroalgae in Tropical Marine Coastal Systems. ECOLOGICAL STUDIES 2012. [DOI: 10.1007/978-3-642-28451-9_16] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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8
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Pohle G, Iken K, Clarke KR, Trott T, Konar B, Cruz-Motta JJ, Wong M, Benedetti-Cecchi L, Mead A, Miloslavich P, Mieszkowska N, Milne R, Tamburello L, Knowlton A, Kimani E, Shirayama Y. Aspects of benthic decapod diversity and distribution from rocky nearshore habitat at geographically widely dispersed sites. PLoS One 2011; 6:e18606. [PMID: 21533220 PMCID: PMC3077369 DOI: 10.1371/journal.pone.0018606] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2010] [Accepted: 03/05/2011] [Indexed: 11/23/2022] Open
Abstract
Relationships of diversity, distribution and abundance of benthic decapods in intertidal and shallow subtidal waters to 10 m depth are explored based on data obtained using a standardized protocol of globally-distributed samples. Results indicate that decapod species richness overall is low within the nearshore, typically ranging from one to six taxa per site (mean = 4.5). Regionally the Gulf of Alaska decapod crustacean community structure was distinguishable by depth, multivariate analysis indicating increasing change with depth, where assemblages of the high and mid tide, low tide and 1 m, and 5 and 10 m strata formed three distinct groups. Univariate analysis showed species richness increasing from the high intertidal zone to 1 m subtidally, with distinct depth preferences among the 23 species. A similar depth trend but with peak richness at 5 m was observed when all global data were combined. Analysis of latitudinal trends, confined by data limitations, was equivocal on a global scale. While significant latitudinal differences existed in community structure among ecoregions, a semi-linear trend in changing community structure from the Arctic to lower latitudes did not hold when including tropical results. Among boreal regions the Canadian Atlantic was relatively species poor compared to the Gulf of Alaska, whereas the Caribbean and Sea of Japan appeared to be species hot spots. While species poor, samples from the Canadian Atlantic were the most diverse at the higher infraordinal level. Linking 11 environmental variables available for all sites to the best fit family-based biotic pattern showed a significant relationship, with the single best explanatory variable being the level of organic pollution and the best combination overall being organic pollution and primary productivity. While data limitations restrict conclusions in a global context, results are seen as a first-cut contribution useful in generating discussion and more in-depth work in the still poorly understood field of biodiversity distribution.
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Affiliation(s)
- Gerhard Pohle
- Huntsman Marine Science Centre, St. Andrews, New Brunswick, Canada.
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9
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Miloslavich P, Klein E, Díaz JM, Hernández CE, Bigatti G, Campos L, Artigas F, Castillo J, Penchaszadeh PE, Neill PE, Carranza A, Retana MV, Díaz de Astarloa JM, Lewis M, Yorio P, Piriz ML, Rodríguez D, Yoneshigue-Valentin Y, Gamboa L, Martín A. Marine biodiversity in the Atlantic and Pacific coasts of South America: knowledge and gaps. PLoS One 2011; 6:e14631. [PMID: 21304960 PMCID: PMC3031619 DOI: 10.1371/journal.pone.0014631] [Citation(s) in RCA: 177] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2010] [Accepted: 01/04/2011] [Indexed: 11/18/2022] Open
Affiliation(s)
- Patricia Miloslavich
- Departamento de Estudios Ambientales and Centro de Biodiversidad Marina, Universidad Simón Bolívar, Caracas, Venezuela.
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10
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Cruz-Motta JJ, Miloslavich P, Palomo G, Iken K, Konar B, Pohle G, Trott T, Benedetti-Cecchi L, Herrera C, Hernández A, Sardi A, Bueno A, Castillo J, Klein E, Guerra-Castro E, Gobin J, Gómez DI, Riosmena-Rodríguez R, Mead A, Bigatti G, Knowlton A, Shirayama Y. Patterns of spatial variation of assemblages associated with intertidal rocky shores: a global perspective. PLoS One 2010; 5:e14354. [PMID: 21179546 PMCID: PMC3002908 DOI: 10.1371/journal.pone.0014354] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2010] [Accepted: 11/20/2010] [Indexed: 11/23/2022] Open
Abstract
Assemblages associated with intertidal rocky shores were examined for large scale distribution patterns with specific emphasis on identifying latitudinal trends of species richness and taxonomic distinctiveness. Seventy-two sites distributed around the globe were evaluated following the standardized sampling protocol of the Census of Marine Life NaGISA project (www.nagisa.coml.org). There were no clear patterns of standardized estimators of species richness along latitudinal gradients or among Large Marine Ecosystems (LMEs); however, a strong latitudinal gradient in taxonomic composition (i.e., proportion of different taxonomic groups in a given sample) was observed. Environmental variables related to natural influences were strongly related to the distribution patterns of the assemblages on the LME scale, particularly photoperiod, sea surface temperature (SST) and rainfall. In contrast, no environmental variables directly associated with human influences (with the exception of the inorganic pollution index) were related to assemblage patterns among LMEs. Correlations of the natural assemblages with either latitudinal gradients or environmental variables were equally strong suggesting that neither neutral models nor models based solely on environmental variables sufficiently explain spatial variation of these assemblages at a global scale. Despite the data shortcomings in this study (e.g., unbalanced sample distribution), we show the importance of generating biological global databases for the use in large-scale diversity comparisons of rocky intertidal assemblages to stimulate continued sampling and analyses.
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Affiliation(s)
- Juan José Cruz-Motta
- Departamento de Estudios Ambientales, Universidad Simón Bolívar, Caracas, Miranda, Venezuela.
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11
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Iken K, Konar B, Benedetti-Cecchi L, Cruz-Motta JJ, Knowlton A, Pohle G, Mead A, Miloslavich P, Wong M, Trott T, Mieszkowska N, Riosmena-Rodriguez R, Airoldi L, Kimani E, Shirayama Y, Fraschetti S, Ortiz-Touzet M, Silva A. Large-scale spatial distribution patterns of echinoderms in nearshore rocky habitats. PLoS One 2010; 5:e13845. [PMID: 21079760 PMCID: PMC2974624 DOI: 10.1371/journal.pone.0013845] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2010] [Accepted: 10/04/2010] [Indexed: 11/18/2022] Open
Abstract
This study examined echinoderm assemblages from nearshore rocky habitats for large-scale distribution patterns with specific emphasis on identifying latitudinal trends and large regional hotspots. Echinoderms were sampled from 76 globally-distributed sites within 12 ecoregions, following the standardized sampling protocol of the Census of Marine Life NaGISA project (www.nagisa.coml.org). Sample-based species richness was overall low (<1-5 species per site), with a total of 32 asteroid, 18 echinoid, 21 ophiuroid, and 15 holothuroid species. Abundance and species richness in intertidal assemblages sampled with visual methods (organisms >2 cm in 1 m(2) quadrats) was highest in the Caribbean ecoregions and echinoids dominated these assemblages with an average of 5 ind m(-2). In contrast, intertidal echinoderm assemblages collected from clearings of 0.0625 m(2) quadrats had the highest abundance and richness in the Northeast Pacific ecoregions where asteroids and holothurians dominated with an average of 14 ind 0.0625 m(-2). Distinct latitudinal trends existed for abundance and richness in intertidal assemblages with declines from peaks at high northern latitudes. No latitudinal trends were found for subtidal echinoderm assemblages with either sampling technique. Latitudinal gradients appear to be superseded by regional diversity hotspots. In these hotspots echinoderm assemblages may be driven by local and regional processes, such as overall productivity and evolutionary history. We also tested a set of 14 environmental variables (six natural and eight anthropogenic) as potential drivers of echinoderm assemblages by ecoregions. The natural variables of salinity, sea-surface temperature, chlorophyll a, and primary productivity were strongly correlated with echinoderm assemblages; the anthropogenic variables of inorganic pollution and nutrient contamination also contributed to correlations. Our results indicate that nearshore echinoderm assemblages appear to be shaped by a network of environmental and ecological processes, and by the differing responses of various echinoderm taxa, making generalizations about the patterns of nearshore rocky habitat echinoderm assemblages difficult.
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Affiliation(s)
- Katrin Iken
- School of Fisheries and Ocean Sciences, University of Alaska Fairbanks, Fairbanks, Alaska, United States of America.
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