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Facilitation by foundation species shapes many terrestrial and benthic communities PowerPoint Presentation
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Facilitation by foundation species shapes many terrestrial and benthic communities

Facilitation by foundation species shapes many terrestrial and benthic communities

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Facilitation by foundation species shapes many terrestrial and benthic communities

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  1. Long-term patch dynamics in the community shaped by bivalves, barnacles, ascidians and red algae: multiple foundation species in the White Sea shallow subtidal

  2. EugeneYakovis Anna ArtemievaMichaelFokin Marina VarfolomeevaNatalia ShunatovaSt.-Petersburg StateUniversity, Russia

  3. Facilitation by foundation species shapes many terrestrial and benthic communities Communities with multiple functionally different foundation species are poorly studied

  4. Locations: 12 m deep Site 1 and 15 m deep Site 2 Site 1 65° 01.2’N 35° 39.7’E Site 2 65° 00.7’N 35° 41.7’E The White Sea

  5. Epibenthic patches (EPs) on the unstructured sediment

  6. Mean density of EPs (m–2):21±2 (Site 1), 6±1(Site 2)

  7. Species diversity in and around EPs unstructured sediment H’=2.62±0.02 (55 cm2 cores) 101 mobile species (78 polychaetes) epibenthic patches H’ = 2.28±0.04 (24±1 cm2 patches) 119 mobile species (72 polychaetes) 111 sessile species (64 bryozans)

  8. Biomass in and around EPs unstructured sediment wet weight of macrobenthic organisms 91 g/m2 epibenthic patches wet weight of macrobenthic organisms 745 g/m2

  9. Overall species diversity H’ = 3.36±0.06 250 species in total (16 x 1 m2 frame) 117±7 species per 1 m2 frame

  10. Epibenthic patches by primary substrate type

  11. Primary substrate types by total area

  12. Total weight of epibenthic organisms within the patches based on different substrate type

  13. Live Serripes groenlandicus stays under the sediment surface and never has sessile organisms attached

  14. Sessile organisms can utilize a shell only when a clam dies

  15. Sessile organisms can utilize a shell only when a clam dies Site 1: 1.8±0.4 unfouled valves of Serripes groenlandicus per m2 on the sediment surface Site 1: 6.7±2.9 live individuals of Serripes groenlandicus per m2

  16. Most sessile organisms live on secondary biogenic substrates (% individuals)

  17. Principal secondary space providers are barnacles and their empty shells, ascidians and red algae

  18. These are 15 top frequent associations between sessile organisms and substrates …

  19. … and these are top 50

  20. Most live barnacles Balanus crenatus are found on primary substrate and conspecifics

  21. Most ascidians Styela spp. are found on barnacles and their empty shells

  22. As a result, epibenthic patches with following structure types are frequent:

  23. Some of them look like this

  24. The observed variation in structure of epibenthic patches: (i)results from patch dynamics or (ii) is just a product of spatial heterogeneity and variable recruitment ? predictions from (ii): > the structure of patches would not depend much on their age > the age-dependent variation of structure would not match one observed in EPs

  25. Number of initially empty Serripes shells exposed S = 34.4 ± 0.8 cm2

  26. 1-2 yrs

  27. 3-4 yrs

  28. 5-6 yrs

  29. 7-8 yrs

  30. 9-10 yrs

  31. Relative areas of principal substrates: shells, live barnacles, dead barnacles, ascidians and red algae by exposure term (shell area as 1) 9-10 yrs 7-8 yrs 5-6 yrs 1-2 yrs 3-4 yrs

  32. Relative abundance of sessile organisms (% ind.) on shells, live barnacles, dead barnacles, ascidians, red algae and other substrates by exposure term 9-10 yrs 7-8 yrs 5-6 yrs 1-2 yrs 3-4 yrs

  33. Mean LogE Shannon diversity of epibenthic assemblages on shells, live barnacles, dead barnacles, ascidians, red algae and other substrates by exposure term 9-10 yrs 7-8 yrs 5-6 yrs 1-2 yrs 3-4 yrs

  34. nMDS of natural and experimental EPs on weights of ascidians, live and dead barnacles, red algae and Shannon diversity (stress=0.08) w/o substrate on Serripes shells on live snails on other substrates

  35. nMDS of natural and experimental EPs on weights of ascidians, live and dead barnacles, red algae and Shannon diversity 1-2 yrs

  36. nMDS of natural and experimental EPs on weights of ascidians, live and dead barnacles, red algae and Shannon diversity 3-4 yrs

  37. nMDS of natural and experimental EPs on weights of ascidians, live and dead barnacles, red algae and Shannon diversity 5-6 yrs

  38. nMDS of natural and experimental EPs on weights of ascidians, live and dead barnacles, red algae and Shannon diversity 7-8 yrs

  39. nMDS of natural and experimental EPs on weights of ascidians, live and dead barnacles, red algae and Shannon diversity 9-10 yrs

  40. nMDS of natural and experimental EPs on weights of ascidians, live and dead barnacles, red algae and Shannon diversity 1-10 yrs 1-2 3-4 5-6 7-8 9-10

  41. The observed variation in structure of epibenthic patches: (i)results from patch dynamics or (ii) is just a product of spatial heterogeneity and variable recruitment ? predictions from (ii): > the structure of patches would not depend much on their age > the age-dependent variation of structure would not match one observed in EPs

  42. The observed variation in structure of epibenthic patches: (i)results from patch dynamics or (ii) is just a product of spatial heterogeneity and variable recruitment ? predictions from (ii): > the structure of patches would not depend much on their age > the age-dependent variation of structure would not match one observed in EPs

  43. The observed variation in structure of epibenthic patches: (i)results from patch dynamics or (ii) is just a product of spatial heterogeneity and variable recruitment ? predictions from (ii): > the structure of patches would not depend much on their age > the age-dependent variation of structure would not match one observed in EPs

  44. The observed variation in structure of epibenthic patches: (i)results from patch dynamics or (ii) is just a product of spatial heterogeneity and variable recruitment ? predictions from (ii): > the structure of patches would not depend much on their age > the age-dependent variation of structure would not match one observed in EPs

  45. Credits Alexander Tcherenkov Nadezhda Tcherenkova Alexey Grishankov Alexandra Yakovis Dmitry Tomanovsky Funding: RFBR grants № 02-04-50020-a, 05-04-48927-a, 05-04-63041-k, 06-04-63077-k, 06-04-58536-z, 06-04-58537-z, 07-04-10075-k, 07-04-08366-z, 08-04-01373-a, 08-04-10109-k, 09-04-10092-k, 10-04-08011-z

  46. Bonustrack

  47. a shell exposed for 9 yrs