A bank of microscopic forms on disturbed boulders and stones in tide pools

Abstract

Disturbed marine habitats contain banks of microscopic forms that develop into macroscopic vegetation under adequate conditions. This study examined seasonal species turnover, timespace community development and species-area relationships of a n assemblage of microscopic forms, on boulders and stones in 2 tidal pools in central Chile (32" 4 6 ' s ; 71" 33' W). A total of 25 taxa were found in the assemblage, with low species turnover throughout the year. The assemblage contained about twice the number of species present In the water column and about half the number present in the n~acroscopic vegetation. Species present in the macroalgal vegetation and in the water column accounted for 7 0 % of the taxa in the assemblage, the remaining 30% suggested propagule sources outside the study area. Colonization and succession experiments indicated that the banks were formed by ephemeral and perennial species. Most perennials are slow-growing and crustose, of IOIY-colonizing capacity, the bank seemed more important for the survival of these perennial species than for fugitwe forms. Species r~chness in the bank correlated w~t h the surface area of boulders. For areas larger than 40 cm2, species richness was significantly higher on individually sampled stones than on equivalent surfaces subsampled from larger boulders, suggesting that species richness follows predictions of the intermediate disturbance hypothesis. The number of species was high, suggesting that disturbance affects the macroscopic expression of diversity rather than the total number of species.

Control of macroalgal blooms at early developmental stages: Pilayella littoralis versus Enteromorpha spp.

“…Investigations of these``banks of microscopic forms'' are rare. A detailed characterization of such an assemblage of microscopic forms, their species composition and turnover, was done for tide pools in Chile (Santelices et al 1995). In these tide pools, both perennial and annual species (a total of 25 taxa) were present as microscopic forms, and the bank seemed more important for the survival of populations of perennial species.…”

Species-area relationships for coral reef fish assemblages of St. Croix, US Virgin Islands

“…Since the early 1920s countless studies on a diversity of taxa, plants (Chemengich 1993, Buys et al 1994, Chiarucci 1996, Singh et al 1996, Falkner & Stohlgren 1997, Morrison 1997, Lawesson et al 1998, invertebrates (Peake & Quinn 1993, Santelices et al 1995, Gasnier et al 1997, Anderson 1998, Baldi & Kisbenedek 1999, birds (Androukaki & Adamantopoulou 1992, Johnson & Patil 1995, Falkner & Stohlegren 1997, mammals (Danell et al 1996, Falkner & Stohlegren 1997 and fish (Angermerier & Schlosser 1989, Oberdorff et al 1995 have explored the species-area relationship in order to characterize assemblages, determine the area needed to adequately sample a desired suite of species, estimate species richness, investigate the effects of disturbance, and define the appropriate size of reserves and natural areas (He & Legendre 1996, Connor & McCoy 1979. Unfortunately, investigations of fish species-area relationships, particularly reef fish, are generally absent from the literature.…”

Macroalgal Distribution Patterns and Ecological Performances in a Tidal Coastal Lagoon, with Emphasis on the Non-indigenous Codium Fragile ssp. Tomentosoides

“…Overall, G. verrucosa was the most abundant species, adding a high recruitment ability to an array of previously described successful lagoon adaptations, including high stress tolerance (Chapter 5, Stokke 1956), high growth and recovery potential (Chapter 5, Hanisak et al 1979, McLachlan & Bird 1986) and strong association with the polychaete facilitator Diopatra cuprea (Chapter 3), together explaining the ubiquity of this species in North American east coast lagoons (Cowper 1978, Goshorn et al 2001, Chapter 2, Humm 1944, Peckol & Rivers 1996 hydrodynamic forcing may frequently generate fragments to the drift algal assemblages (Chapter 2, 3, 4). Also, because unattached algae in general do not become reproductive (Norton & Mathieson 1983), the algae attached to the oyster reefs ensures that a propagule bank is constantly produced (Santelices et al 1995). Thus, reef attached algae probably reduce the likelihood of local extinctions on the mudflats (where waves and currents constantly remove algae) by providing a continuous supply of fragments.…”