| dc.contributor.author | Schneider, Friederike Irmgard. | en_US |
| dc.date.accessioned | 2014-10-21T12:34:50Z | |
| dc.date.available | 1990 | |
| dc.date.issued | 1990 | en_US |
| dc.identifier.other | AAINN64468 | en_US |
| dc.identifier.uri | http://hdl.handle.net/10222/55190 | |
| dc.description | The distribution of invertebrates in relation to small-scale variation of macrophytes within the Pomquet Harbour, Nova Scotia, eelgrass bed was examined. Previous work has shown that the abundance and species composition of invertebrates within seagrass beds are closely dependent upon the vegetation of the beds as a whole, but little attention has been paid to within bed variability. | en_US |
| dc.description | Eelgrass cover in the shallowest portion of the Pomquet Harbour eelgrass bed is patchy, apparently due to ice rafting during the winter. Drift and epiphytic macroalgae, which compose a major part of the vegetation biomass, occur in clumps, but their distribution is largely unaffected by small-scale variation in eelgrass cover. | en_US |
| dc.description | The abundance of epifauna within the seagrass bed tended to vary with vegetation distribution. Of seven common species, one was associated with eelgrass, four with drift algae, and two showed no consistent affinity. | en_US |
| dc.description | In artificial gaps created to test the effect of ice scoured clearings, numbers of infauna and epifauna were initially depressed but reached control levels much more rapidly than did eelgrass biomass. This was associated with a rapid return of macroalgal biomass to values found in unmanipulated areas, suggesting that macroalgae provide a suitable habitat for many invertebrates. | en_US |
| dc.description | The apparent association of some invertebrates with macroalgae instead of eelgrass suggested that invertebrates were discriminating among macrophytes. Colonization experiments were carried out using plastic to simulate vegetation shapes of different complexity and differing epiphytic algal cover. Both shape and epiphyte cover were important, but for many species, the effect of epiphyte cover was secondary to that of shape. To determine whether differences in shape affected the efficacy of a macrophyte as cover from predators, laboratory predation experiments were conducted. Predation loss was unaffected by macrophyte type. | en_US |
| dc.description | In summary, vegetation heterogeneity in the Pomquet Harbour eelgrass bed provides invertebrates with a variety of habitats. When gaps are created in eelgrass cover, the rapid influx of macroalgae permits the invertebrate assemblage to recover much faster than the eelgrass itself. Differential distribution of invertebrates within the seagrass bed and during recovery is the result of substrate selection largely on the basis of macrophyte shape. | en_US |
| dc.description | Thesis (Ph.D.)--Dalhousie University (Canada), 1990. | en_US |
| dc.language | eng | en_US |
| dc.publisher | Dalhousie University | en_US |
| dc.publisher | | en_US |
| dc.subject | Biology, Ecology. | en_US |
| dc.subject | Biology, Oceanography. | en_US |
| dc.title | The response of invertebrates to the disturbance of a seagrass bed by simulated ice rafting. | en_US |
| dc.type | text | en_US |
| dc.contributor.degree | Ph.D. | en_US |
