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Don Maurer 《Marine Ecology》1983,4(3):263-274
Abstract. Animal-animal interactions are recognized as critical in benthic invertebrate recruitment. The hypothesis tested was that benthic recruitment is more successful in low densities of infaunal suspension feeders than in high densities. Densities of young hard clams Mercenaria mercenaria (L.) ranging from 82.5 to 330m-2 were placed in defaunated boxes of sand. The mean number of species, mean number of individuals, mean wet weight biomass, mean species richness and mean dominance index per sample were calculated per density of hard clams from May to October. The experiment did not support the hypothesis. It was concluded that feeding behaviour of dense populations of M. mercenaria did not preclude successful recruitment of other benthic species.  相似文献   
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P. Fong  D. Lirman 《Marine Ecology》1995,16(4):317-335
Abstract. Three mechanisms aiding recovery and expansion of a population of Acropora palmata on 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 of A. palmata had 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 suggests A. palmata is 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 storms).  相似文献   
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Changes in North Sea gadoid stocks   总被引:5,自引:1,他引:5  
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Vertical and horizontal distributions are described for megalopae of 11 brachyuran taxa common to the lower Chesapeake Bay and adjacent shelf. Three distribution patterns are apparent from horizontal distribution.
1. (1) More than 75% of the megalopae of estuarine adults, such as Hexapanopeus angustifrons, Neopanope sayi, Panopeus herbstii, Rhithropanopeus harrisii and Pinnotheres ostreum, are retained in estuarine waters.
2. (2) The megalopae of three estuarine taxa, Callinectes sapidus, Uca spp. and Pinnixa sp., are most abundant on the shelf.
3. (3) More than 90% of the megalopae of the shelf species, Portunus sp., Cancer irroratus and Libinia spp. remained in shelf waters.
Vertical distributions indicate the megalopae of a majority of estuarine crabs are epibenthic when waters are stratified. Exceptions include the megalopae of both Rhithropanopeus which are found slightly shallower in well mixed waters and Callinectes sapidus which are generally most abundant in the neuston. The megalopae of two shelf species, Portunus sp. and Cancer irroratus, reach highest densities in surface waters, while those of Libinia spp. are common in the epibenthos.Megalopal distributions analyzed with respect to water column stratification show megalopae never reached highest densities within the layer of the pycnocline. The megalopae of five species show significant shifts in vertical distributions between stratified and homogeneous water columns.  相似文献   
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