INVESTIGADORES
DALEO Pedro
artículos
Título:
Crab bioturbation and herbivory reduce pre- and post-germination success of Sarcocornia perennis in bare patches of SW Atlantic salt marshes
Autor/es:
ALBERTI, J.; ESCAPA, M; DALEO, P.; MENDEZ CASARIEGO, A.; IRIBARNE, O.
Revista:
MARINE ECOLOGY PROGRESS SERIES
Referencias:
Año: 2010 vol. 400 p. 55 - 61
ISSN:
0171-8630
Resumen:
<!-- /* Style Definitions */ p.MsoNormal, li.MsoNormal, div.MsoNormal {mso-style-parent:""; margin:0cm; margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:12.0pt; font-family:"Times New Roman"; mso-fareast-font-family:"Times New Roman"; mso-ansi-language:ES; mso-fareast-language:ES;} @page Section1 {size:612.0pt 792.0pt; margin:70.85pt 3.0cm 70.85pt 3.0cm; mso-header-margin:36.0pt; mso-footer-margin:36.0pt; mso-paper-source:0;} div.Section1 {page:Section1;} -->             Colonization of bare spaces is a key process during community development given that pioneers usually have positive and negative effects on the forthcoming species. A variety of biotic and abiotic factors influence the process of colonization of bare surfaces. In salt marshes, however, the emphasis has been on abiotic factors and plant-plant interactions, while comparatively little attention has been paid to the role of plant-animal interactions in the successful colonization of pioneer plants. Thus, the goal of this study was to evaluate if bioturbation and herbivory by the burrowing crab Neohelice (Chasmagnathus) granulata affected the number of seedlings of the pioneer plant Sarcocornia perennis in SW Atlantic salt marshes. To evaluate this, we conducted an experiment using exclosures deployed at different times (post-dispersal and post-germination). The results showed that post-germination exclosures had 62% less seedlings than post-dispersal exclosures but 8 times more than plots always accessible to crabs. We also used glass beads to experimentally evaluate the potential effect of crab bioturbation on seed availability, and we used one year-old transplants to evaluate if herbivory could explain post-germination mortality. Crab bioturbation reduced by 56% the number of glass beads on the surface and transplants were highly consumed when crabs were present. These results suggest that seed burial by bioturbation exerts a pre-germination control while herbivory exerts a post-germination control. These results also highlight the importance of considering biotic factors when analyzing the success of marsh plants colonizing bare surfaces.