Pa. Camus et Na. Lagos, SPATIOTEMPORAL VARIATION OF RECRUITMENT I N SESSILE INTERTIDAL ASSEMBLAGES FROM NORTHERN CHILE, REV CHIL HN, 69(2), 1996, pp. 193-204
In this paper we assessed temporal and spatial variation patterns of r
ecruitment of sessile species during a 14 month period for two similar
rocky intertidal assemblages in northern Chile: Chanavayita and Yape
(ca. 20 degrees 41' S), which were 4 km appart. A set of experimental
quadrants in each site located at three tidal levels within the mid-hi
gh intertidal zone were repeatedly denudated every 1.33 months to obta
in time-independent recruitment estimates. We recorded a total of 25 a
nd 20 species for Chanavayita and Yape respectively during the study p
eriod. Compositional similarity was lower between sites (40 +/- 10%; J
accard's index) than within sites (more than 55%). Only three species
recruited in all periods: the barnacles Jehlius cirratus (Darwin) and
Norochtamalus scabrosus (Darwin) and the Chlorophyta Ulva rigida C. Ag
ardh, which are the dominants in the adult assemblage. Community recru
itment showed a seasonal pattern both at site and quadrat levels, main
ly for algal species, and there was no interaction between time and ti
dal level. A cross-correlation analysis showed no temporal dependence
between sites. At the assemblage level, recruitment decreased from low
to high tidal levels, but there were opposite trends among individual
species. Spatial and temporal recruitment frequencies were positively
correlated in both sites. We discuss the adequacy of traditional conc
epts such as recruitment schedule and early and late successional spec
ies, and some predictions of the supply-side ecology frame.