摘要:

Abstract.Spongaster tetras tetrasEhrenberg has long been considered by palaeontologists as a species indicative of warm (>21 C) sea‐surface temperatures (SSTs) and tropical/subtropical conditions. However. a comparison of the Plio‐Pleistocene record ofS. t. tetrasin the eastern equatorial Pacific (Ocean Drilling Program Hole 677A) with CaCO3, δ18O, and δ13C records reveals thatS. t. tetrasis most commonly present during periods of intense upwelling, often coinciding with isotopically identified glacial stages. when surface productivity and salinity are high, and SST is expected to be relatively low. MaximumS. t. tetrasabundance (1.8% of radiolaria counted) occurred during a cool interglacial. when productivity and salinity were high, wind‐driven upwelling intense, and SST relatively warmer than during glacial maxima. It appears that in the eastern equatorial Pacific upwelling system, SSTs are generally too cold (<21 C) forS. t. tetrasto survive; however, S.t. tetrascan tolerate (with populations1.8%) if this is coupled with relatively warm SSTs. This micropalaeontological study Corroborates the findings of an earlier research program on livingS. t. tetrascultures (Andersonet al., 19

ISSN:0173-9565    

DOI:10.1111/j.1439-0485.1995.tb00412.x

出版商:Blackwell Publishing Ltd    

年代:1995

数据来源: WILEY

摘要:

Abstract.The infralittoral benthos was studied on three islands of the Northern Sporades in the Aegean Sea. Thirteen stations were sampled on both hard and soft substrata and 408 taxa were identified, some of zoogeographical interest. Multivariate statistical methods such as classification, ordination and Similarilies Terms Analysis were combined with existing ecological information to delineate the various communities present and to point to the indicator species characterising them. The communities were then defined using the indicator species and their affinities to typical biocoenoses. The main factor responsible for the observed distribution proved to be the type of substratum (algal cover or sediment type), which reflects the light and hydrodynamic conditions. The observed bathynietric zonation was similar lo that of the Balearic Islands in the western Mediterranean.

ISSN:0173-9565    

DOI:10.1111/j.1439-0485.1995.tb00413.x

出版商:Blackwell Publishing Ltd    

年代:1995

数据来源: WILEY

摘要:

Abstract.This paper reports on the temporal distribution of microbial biomass, over a I‐month survey during austral suinmer 1990. at two sampling stations in Terra Nova Bay (Antarctica) by means of biochemical methodologies such as ATP (adenosine triphosphate) and LPS (lipopolysaccharides). Microbial estimates. derived from ATP measurements. showed an unstable temporal trend and a range characteristic for water with low or. seldom. moderate trophism. Biomass decreased with increasing depth. and photo‐autotrophic organisms seem to dominate the whole microbial assemblage. The bacterial population, as derived from LPS determinations, did not show much variability and was well‐correlated to other microbiological and chemical parameters. Our data showed that larger mic‐roplankters were dominant. but that sometimes pico‐sized organisms contributed about 60% to the microbial biomass; this emphasizes the ‘still poorly‐known’ importance of microbes in Anta

ISSN:0173-9565    

DOI:10.1111/j.1439-0485.1995.tb00414.x

出版商:Blackwell Publishing Ltd    

年代:1995

数据来源: WILEY

摘要:

Abstract.Three mechanisms aiding recovery and expansion of a population ofAcropora palmataon a patch reef that was directly in the path of Hurricane Andrew were documented: rapid wound healing, high rates of asexual recruitment, and rapid growth rate of the new recruits. In addition, the growth pattern of new recruits was assessed in order to quantify the initial sequence of Structural changes during the transition from recruit to adult morphology. Wound healing was initially rapid (1.59 cm of linear growth per month). but slowed with time. Nine months after the storm, 72% of 218 hurricane‐generated fragments ofA. palmatahad cemented to the bottom, becoming new asexual recruits. Within 18 months of the storm, the number of fragments in the same area had increased to 271, average fragment size was larger, and 94% had become recruits. Recruits showed complex patterns of branch formation, including rapid growth of solitary proto‐branches, differential growth of proto‐branches dependent on recruit orientation, and dominance within aggregates of proto‐branches. We present a conceptual model that suggestsA. palmatais adapted to disturbances of both low intensity and high frequency (conditions typical of reef flat zones) and episodic high intensity and low frequency events (hurricanes and tropical

ISSN:0173-9565    

DOI:10.1111/j.1439-0485.1995.tb00415.x

出版商:Blackwell Publishing Ltd    

年代:1995

数据来源: WILEY

摘要:

Abstract.Annual growth rates of gorgonians in the Indo‐Pacific region are reported ror the first tinie. A method of measuring gorgonian growth using periodic photographic monitoring that is sensitive to horizontal growth and changes in growth foci but that does not require tedious underwater measurements is applied. Growth parameters of five species of gorgonians from three Families (Plexauridae. Melithaeidae. andSubergorgiidae) were monitored over a period of 18 months using this method. Growth rates ranged from 2.30 cm a‐1to 7.88 cm. a‐1in the highly sedimented waters of Singapore. The maximum number of branches added per year ranged from 1.7 to

ISSN:0173-9565    

DOI:10.1111/j.1439-0485.1995.tb00416.x

出版商:Blackwell Publishing Ltd    

年代:1995

数据来源: WILEY

摘要:

Book reviewed in this article:Ansell, A. D., R. N. Gibson&M. Barnes(Eds.), H. Barnes(Founder Ed.): Oceanography and Marine Biology. An Annual Review. Vol. 32.Fenchel, T.&B. J. Finlay: Ecology and Evolution in Anoxic Worlds

ISSN:0173-9565    

DOI:10.1111/j.1439-0485.1995.tb00417.x

出版商:Blackwell Publishing Ltd    

年代:1995

数据来源: WILEY