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Title: Population biology of the intertidal kelp, Alaria marginata Postels and Ruprecht: A non-fugitive annual,
Description: Persistence of annual plant populations requires sufficient seeds and suitable habitat for development and growth each year. Competition with perennials may prevent within site persistence and result in "fugitive" annual populations. Comparisons have been made between the population biology of annual macroalgae and terrestrial plants, but demographic information necessary to make strong comparisons is lacking for most of these algae, and life history differences may make such comparisons questionable. We studied population dynamics of the kelp Alaria marginata to determine if it was an annual and, if so, how populations persisted. This kelp is the dominant macroalga on exposed mid to low rocky intertidal shores along the Big Sur coast of California. Experimental clearings at two sites were used to assess recruitment timing and survivorship. Sporophytes were collected monthly to determine growth and fecundity. Recruitment occurred in late winter to early spring, primarily on geniculate corallines and residual A. marginata holdfasts. Thinning was inversely related to density, and occurred during the February through July growing season as larger thalli rapidly increased in length (up to 1.4 m month-1) and formed a thick canopy. Sorus development was positively related to size, began as early as March, peaked in late August-October, and decreased as adults were removed by winter surf. Spore release was generally highest (108-109 spores individual-11 h-1) between October and January and associated with high water motion. Survivorship of sporophytes beyond one year was < 1%, showing the populations were annual. Field observations and experiments on effects of canopy clearing, season of clearing, and influence of substrate type on recruitment were done to assess how these annual populations persist. Massive spore production at the onset of fall storms, survival of microscopic stages for 3-4 months facilitated by microhabitat refuges, rapid growth, large size and rapid maturation of sporophytes contributed to persistence. Furthermore, the dense stands with thick canopies may suppress potential competitors via shading and abrasion. Rather than being a fugitive, this combination of growth and life history features enables A. marginata and perhaps other large, annual kelps to maintain perennial populations. © 2005 Elsevier B.V. All rights reserved., Cited By (since 1996):9, CODEN: JEMBA, ,
Author: McConnico, Foster
Date: 2005-01-01T00:00:00Z

Title: Rammed by the Exxon Valdez,
Description: , , ,
Author: Foster
Date: 1991-01-01T00:00:00Z

Title: Damage and recovery in intertidal Fucus gardneri assemblages following the Exxon Valdez oil spill,
Description: Cited By (since 1996):19 Seaweeds, CODEN: MESED, In March 1989, the 'Exxon Valdez' spilled over 10 million gallons (ca 38 million I) of crude oil into Prince William Sound, Alaska , USA. The spill was followed by massive clean-up using hot seawater at high pressure as well as other mechanical and chemical techniques. We studied initial damage and subsequent recovery in the upper margin of the Fucus gardneri assemblage on protected shores by comparing sites that were unoiled, oiled and cleaned with hot water at high pressure, and oiled but less intensely cleaned. F. gardneri cover averaged 80% on unoiled sites but< 1 % on all oiled and cleaned sites 18 mo after the spill. The abundances of barnacles, littorine snails and limpets varied among sites and species, and this variation was associated in part with differences in their life histories. F. gardneri cover was still extremely low on oiled and cleaned sites 2.5 yr after the spill. Holdfasts that persisted after cleaning did not resprout. F. gardneri recruitment was lowest at intensely cleaned sites, and most recruits occurred in cracks near adults. Recruits were less abundant under adult canopies but placing canopies over recruits did not decrease their survivorship over 5 mo. Natural weathering of tar was rapid, with most marked patches gone in less than 1 yr. We conclude that intense mechanical cleaning following this oil spill increased damage and slowed recovery. Such methods should be avoided if reduction of environmental damage is the primary objective of post-spill management decisions. The recovery of F. gardneri at its upper margin might be enhanced by devices that retain moisture and increase substratum rugosity., ,
Author: Devogelaere, Foster
Date: 1994-01-01T00:00:00Z

Title: Natural History Observations of Hawaiian Garden Eels, Gorgasia hawaiiensis (Congridae: Heterocongrinae), from the Island of Hawai'i, Natural History Observations of Hawaiian Garden Eels
Description: Garden eels occur worldwide in the tropics, but little is known about their biology and ecology. We studied Hawaiian garden eel (Gorgasia hawaiiensis) colonies near Kawaihae, Hawai'i, to investigate multiple aspects of basic biology of this species. Colonies of G. hawaiiensis occurred at depths from 16 to 36 m in soft-bottom habitat adjacent to rocky reefs. Highest burrow densities (up to 40 eels m-2) were in shallower water, and large (~10 mm diameter) burrows were more abundant, less dense, and commonly found in pairs in deeper water. Eels emerged around sunrise and withdrew and covered burrow entrances around sunset. Age was estimated from annual rings in sectioned otoliths (n = 17) and modeled to suggest fast growth to a maximum size of ~600 mm total length and a maximum age of 6 yr. Prey size and eel anatomy suggest that these fish feed by ingesting planktonic prey and processing them in the esophagus. The most common food items were small (<0.5 mm) demersal harpacticoid, cyclopoid, and calanoid copepods and unidentified fish eggs. These and other observations indicate that G. hawaiiensis is abundant, has a high population turnover rate, and may enrich sandy-bottom habitat within their beds by facilitating energy flow from the water column to the benthos. © 2017 by University of Hawai'i Press., Export Date: 17 April 2017, Article
Author: Donham, Foster, Rice, Cailliet, Yoklavich, Hamilton

Title: Book review: Connell, S.D. and Gillanders, B.M., Marine Ecology,
Description: , , ,
Author: Foster

Title: Growth rate and potential climate record from a rhodolith using 14C accelerator mass spectrometry,
Description: , , , Rhodoliths, free-living calcareous red algae, create large and diverse habitats worldwide. Although these plants are abundant and ecologically important, little is known about their growth rate. We determined the growth rate for an individual rhodolith, Lithothamnium crassiusculum, from the southern Gulf of California through 14C analysis using accelerator mass spectrometry (AMS) to be 0.6 mm yr21. This growth rate suggests large L. crassiusculum, which have been found with radii in excess of 6 cm, may live over 100 yr. Declines in the D14C record associated with the large El Nin˜o events of 1957, 1982, and 1992 indicate 14C analysis may lead to identification of important climate events in the more distant past. The ability to determine changes in past ocean circulation related to changes in past climatic conditions through AMS 14C analysis of rhodoliths would increase the geographic range of available climate records from the tropical oceans to the entire global ocean and potentially allow for the determination of past climate conditions from rhodoliths in fossil beds., ,
Author: Frantz, Kashgarian, Coale, Foster
Date: 2000-01-01T00:00:00Z

Title: An in situ study of recruitment, growth and survival of subtidal marine algae,
Description: , , ,
Author: Neushul, Foster, Coon, Woessner, Harger
Date: 1976-01-01T00:00:00Z

Title: Dr. Michael Neushul,
Description: , , ,
Author: Reed, Norris, Foster
Date: 1994-01-01T00:00:00Z

Title: Settlement, growth and reproduction of benthic algae within Macrocystis forests in California,
Description: , , ,
Author: Harger, Coon, Foster, Neushul, Woessner
Date: 1981-01-01T00:00:00Z

Title: The validity of using morphological characteristics as predictors of age in the kelp, Pterygophora californica (Laminariales, Phaeophyta),
Description: Previous studies have used stipe ring counts to estimate the age of several species in the Laminariales. Although this method is widely accepted, it has rarely been validated. To test the validity of aging Pterygophora californica by counting rings formed in the stipe, we sampled plants of known age between 1.0 and 4.4 yr old and plants with a calculated age of 12 yr. For a given cohort, the number of complete rings closely approximated the known age in years. indicating ring counts are a reliable method for estimating the age structure of P califomica populations. However, ring counts from individual plants of known age can vary by ± 2 yr (95 % CI), and among readers counting the same plants by ± 1 yr (95 % CI). Single plants, there fore, could not be reliably aged by ring counts Linear relationships between 2 morphometric measures (stipe length and stipe diameter) and number of rings varied both within and between stands and sites, suggesting these measures are not reliable for estimating the age of this alga in the areas sampled. Stand density may be an important factor contributing to the variation in these morphome tric measures. Short-term (22 wk) field manipulations of stand density showed that plants at high density (30 plants m^-2) grew faster in stipe length and slower in stipe diameter than those at medium (6 plants m^-2) and low (2 plants m^-2) densities. Plants collected in a multi-site survey, however, showed no relationship between stand density and stipe morphology, indicating factors other than density also influence stipe growth Short-term (22 wk) field manipulations, which reduced ambient light levels by up to 58 %. had no significant effects on stipe morphology., , ,
Author: Hymanson, Reed, Foster, Carter
Date: 1990-01-01T00:00:00Z

Title: Let seeping oil lie,
Description: , , ,
Author: Foster
Date: 1993-01-01T00:00:00Z

Title: The effects of insolation and grazing on populations of the splash zone alga Prasiola meridionalis (Chlorophyta),
Description: Field experiments at two sites assessed the effects of insolation and gastropod grazing on the distribution and abundance of Prasiola meridionalis Setchell et Gardner, a green alga that occurs in the upper splash zone (supralittoral) on guano-covered rocks. At site 1, a sun-exposed horizontal rock where the alga occurs seasonally and grazers were rare, blades appeared in the early spring and died back in early summer. Lack of gastropod grazers and persistence of blades in experimentally shaded plots showed that increased insolation or some associated factor (or factors) was responsible for temporal variation at this site. At site 2, the alga grew in a distinct, perennial band on a shaded vertical rock face with abundant gastropod grazers. These grazers were excluded from long vertical plots that extended from the lower portion of the P. meridionalis band down to a zone of the red alga Endocladia muricata (Postels et Ruprecht) J. Agardh more than 2 m below. The results showed that grazing set the proximate lower limit of P. meridionalis at site 2, and variation in the abundance of the alga within its zone at this site was associated with seasonal climate changes and feeding by mites. Thus, while insolation and grazing can both affect populations of P. meridionalis, their relative importance varied between sites., Cited By (since 1996):4, Seaweeds, CODEN: PYCOA, ,
Author: Anderson, Foster
Date: 1999-01-01T00:00:00Z

Title: Distribution and recruitment of subtidal geniculate coralline algae,
Description: , , , Geniculate coralline algae are common members of kelp forest communities. The structure provided by their stiff branches greatly influences the abundance and species composition of benthic animals and can affect associated algae by inhibiting recruitment, but the branches are themselves substrate for a large number of other taxa. However, other than qualitative observations, little is known about the within-site distribution, recruitment, and growth of these algae. We examined the distribution of the dominant corallines at a subtidal site in central California. Abundances of Calliarthron tuberculosum (Post. & Rupr.) Dawson, Bossiella californica ssp. schmittii (Manza) Johans., Calliarthron cheilosporioides Manza, Corallina vancouveriensis Yendo, and unidentifiable juveniles were determined at depths of 10, 15, and 20 m and on horizontal rock, vertical rock, and cobble. Calliarthron tuberculosum was most abundant (≤ 39% cover) at all depths, growing primarily on horizontal surfaces. Vertical surfaces and cobbles were dominated by B. californica ssp. schmittii (40 and 15% cover, respectively). These two most abundant species had the highest cover at 15 m. Calliarthron cheilosporioides and C. vancouveriensis were relatively rare (< 1% cover) and generally grew on horizontal rocks and at shallower depths. Unidentified juveniles were also rare and occurred mainly on horizontal rocks and cobbles at 20 m. The settlement and growth rates of coralline crusts and the initiation and growth rates of young erect fronds from these crusts were determined in clearings made in the spring and fall at the three depths. Crust densities and diameters were highest at 10 m and in spring clearings. Settlement and growth tended to decrease with increasing depth. Trends were similar in fall clearings, but initial settlement was lower. Initiation and growth of fronds decreased with depth and were also higher in fall clearings. These variations in depth and substrata distribution, as well as settlement and growth, suggest there is considerable variation in the population biology between species in this group of subtidal plants., ,
Author: Konar, Foster
Date: 1992-01-01T00:00:00Z

Title: The Santa Barbara oil spill Part 2,
Description: The initial effects of the Santa Barbara oil spill on intertidal and kelp bed organisms were studied. Based on earlier surveys, the greatest negative biological change at a sample station after the spill was the loss of 16 plant species. However, losses in species were correlated in most cases with sand movement, and may have been related to the severe storms which occurred before and during the oil spill. Although gross species changes were not correlated with oil dosage, severe damage occurred in intertidal surf grass and barnacle populations as a result of the oil pollution. Potential long-term biological effects of the continuing pollution are discussed., , ,
Author: Foster, Neushul, Zingmark
Date: 1971-01-01T00:00:00Z

Title: Effects of shade from multiple kelp canopies on an understory algal assemblage,
Description: We examined the effects of shade from multiple kelp canopy layers (surface Macrocystis pyrifera canopy, understory Pterygophora californica canopy), both individually and in combination, on an understory algal assemblage in a central Californian kelp forest. The removal of both kelp canopies resulted in a dense recruitment of the understory brown alga Desmarestia ligulata that formed a third canopy layer, which significantly decreased bottom light and the abundance of understory red algae. We subsequently created an additional canopy treatment by removing this third canopy layer. In general, the understory red algae fluctuated seasonally with winter swell intensity, changes in kelp canopy cover, and grazing; and although species richness increased significantly with increased bottom light, red algal bottom cover did not respond significantly to the canopy clearings until 2 yr after the canopies were initially cleared. Red algal cover within the Pterygophora canopy treatment was similar to that in the control treatment. In the absence of Pterygophora, the Macrocystis canopy treatment and 'no canopy' treatment were found to have greater red algal cover and species richness. Individual understory species were rare, which resulted in small effects sizes and thus low statistical power. However, when grouped post hoc, according to how they responded to the canopy clearings (i.e. response groups), we were able to detect canopy treatment effects as much as 1 yr earlier. This method identified that some understory red algae adapted to areas of canopy removal (light-adapted), and others adapted to a variety of light regimes (shade-tolerant). We were able to classify the light-adapted algae into 2 subgroups: the high-light species and the intermediate-light species. Although this method of grouping was done post hoc, our results indicate that it may provide the clearest assessment of how understory algae respond to shading from kelp canopies., Cited By (since 1996):40, Seaweeds, CODEN: MESED, ,
Author: Clark, Edwards, Foster
Date: 2004-01-01T00:00:00Z

Title: The algal turf community in the nest of the ocean goldfish (Hypsypops rubicunda),
Description: , , ,
Author: Foster
Date: 1972-01-01T00:00:00Z

Title: Management of artificial reefs designed to support natural communities,
Description: , , , Pendleton Artificial Reef (PAR) was designed to determine the potential of artificial reefs for mitigating possible losses of kelp-reef habitat caused by operation of coastal power plants. In an attempt to alter natural succession on PAR, massive transplants (hundreds ofindividuals) of two kelp species (Macrocystis pyrifera and Pterygophora californica) and juvenile abalone (Hatiotis rufescens; thousands of individuals) have been conducted. Although the PAR site once supported a kelp forest, kelp transplant efforts were not successful, principally because of intensive grazing by two herbivorous fish; halfmoon and opaleye. Similarly, abalone transplantation was not successful, probably because of crab (Cancer spp,) predation and lack of suitable food. In hindsight, these attempts at manipulating succession may have been successful if the densities of grazing fish were artificially reduced, if abalone additions were delayed until more algae were present, and if abalone transplant techniques were used that would minimize predation. Management of artificial reefs should not be limited to only initial planning, but should also consider manipulating succession after placement. Initial planning should consider the physical and chemical environment (past and present), the biological environment (e,g" location with respect to surrounding communities that could influence dispersal and/or attraction of desirable or undesirable organisms), the design, size, and configuration of the artificial habitat relative to local natural habitats, as well as other factors that affect the quality of the subhabitats (e,g" construction material, interstitial volume, rugosity of the substratum). After an artificial reef has been constructed, there are additional factors that will influence community development. These include timing of reef installation (e.g., availability of spores and larvae to colonize the reef) and possible post reef placement management techniques (e.g., transplantation or removal of select species to alter natural succession). Our general conclusions with respect to succession on PAR is that although initial reef planning factors are important, these are subordinate to reef management techniques after installation (e.g., manipulation of prey/predator densities; addition or removal of select species to direct and/or disturb community succession)., ,
Author: Carter, Jessee, Foster, Carpenter
Date: 1985-01-01T00:00:00Z

Title: Rhodolith bed diversity in the Gulf of California: The importance of rhodolith structure and consequences of disturbance
Description: 1. Rhodolith beds, unattached coralline reefs, support a high diversity and abundance of marine species from both hard and soft benthos. We used surveys in multiple shallow (3-20 m) beds in the Gulf of California to (1) examine seasonal patterns in associated floral and faunal diversity and abundance, (2) compare differences in faunal associations between rhodolith beds and adjacent sedimentary habitats, (3) examine the importance of complexity of rhodolith structure to community structure, and (4) estimate the impact of anthropogenic disturbance on rhodoliths and associated species. 2. Macroalgal richness was seasonal, and beds supported higher richness in winter (to 36 species) than summer (6-7 species), primarily due to foliose red algae. Strong seasonal variation in the abundance of dominant cover organisms was due to a shift from macroalgae and mat-forming colonial invertebrate species to microalgae. 3. The community in a rhodolith bed of high-density thalli (El Coyote average ∼11000 thalli/m -2) had higher richness (52 versus 30 species) and abundance of epibenthic and crypto- and infaunal species compared with an adjacent sand community. Species diversity and abundance was particularly high for unique cryptofaunal organisms associated with rhodolith interstices. Cryptofauna reached average densities of 14.4 organisms/cm -3 rhodolith, the majority of which were crustaceans, polychaetes and cnidarians along with rhodolith-specific chitons. 4. Results from sampling across a range of rhodolith morphs in the El Requeson bed (with lower average cryptofaunal densities of 2.3 organisms/cm -3) revealed that the total organisms supported by a rhodolith significantly increased with both complexity (branching density) and space available (thallus volume). These data suggest that reducing the population size structure, structural complexity and cover of living rhodoliths could decrease species richness and abundance. 5. While disturbance is a natural feature of these free-living beds, increased anthropogenic disturbance from trawling, anchoring and changes in water quality can directly impact the bed community through substrate alteration. Commercial fishing threatens rhodolith beds in the Gulf of California by decreasing rhodolith size and increasing sedimentation and burial rates. In addition to reducing direct destruction, conservation efforts should also focus on decreasing practices that breakdown thalli. Copyright © 2003 John Wiley & Sons, Ltd., Cited By (since 1996):67, CODEN: AQCOE
Author: Steller, Riosmena-Rodriguez, Foster, Roberts
Date: 2003-01-01T00:00:00Z

Title: Benthic succession on an artificial reef designed to support a kelp-reef community,
Description: , , , Pendleton Artificial Reef (PAR) was constructed to determine the potential of artificial reefs to mitigate for possible losses of kelp-reef habitat resulting from operation of coastal power plants. Placed in August 1980, PAR consists of eight boulder modules (some topped with cobble) on a featureless sand bottom at a depth of 13.1 m below MLLW. We studied benthic succession on PAR from September 1981 through August 1983 using a point quadrat sampling technique to describe abundances and vertical distribution of organisms. During this period, small foliose and filamentous algae growing on or over other organisms accounted for 56% of the overstory cover. Cryptoarachnidium (a sediment fixing, encrusting ectoproct) and barnacles accounted for 66% of the understory cover. Cryptoarachnidium was particularly abundant on all modules, while algal turf cover was highest on modules constructed primarily of boulders. On module crests where light and water motion were highest, algal turf was greatest and negatively correlated with erect ectoprocts that were greatest on the slopes of modules. Since erect ectoprocts may inhibit algal colonization and were most abundant on the slopes, we suggest that light, turbidity, and competitive interactions with erect ectoprocts limit the comparatively high cover of algal turf to the module crests. Cover of algal turf was also greatest during periods of clear water in late fall and early winter, while erect ectoproct cover increased during the study period. Cryptoarachnidium cover increased rapidly during the first year after reef placement and stabilized during 1982-1983. Barnacles were the only organisms to show a decline in abundance during the study period. PAR has been in place over 3 years, but relatively to a local natural reef, is still dominated by early successional species. This phenomena appears to result from a number of factors, but especially environmental conditions at the time of reef placement and the isolation of PAR from other shallow reefs in the area., ,
Author: Carter, Carpenter, Foster, Jessee
Date: 1985-01-01T00:00:00Z

Title: Diver disturbance in kelp forests,
Description: Recreational SCUBA diving has greatly increased in the past 20 years and has potential to cause significant disturbances to subtidal reefs. While diver disturbance on coral reefs has been assessed in a number of studies, disturbances in temperate kelp forests have not been previously examined. We estimated diver disturbance in southern Monterey Bay giant kelp, Macrocystis pyrifera, forests by following 42 divers in summer 1997 and recording their activity. During a 0.5 hour dive, the average diver contacted the bottom 43 times, touched 4 animals, and detached 2 algal blades. An estimated 65,000 diver-days are spent in these kelp forests every year, resulting in a potential loss of 130,000 algal blades and considerable benthic disturbances. The effects of these impacts and mitigation for them should be considered in proposals to establish and manage marine protected areas., Cited By (since 1996):2, Ecology, Seaweeds, ,
Author: Schaeffer, Foster, Landrau, Walder
Date: 1999-01-01T00:00:00Z

Title: Living rhodolith beds in the Gulf of California and their implications for paleoenvironmental interpretation,
Description: Subtidal surveys in the southwestern Gulf of California indicate that rhodolith beds are widely distributed, major sources of carbonate sediments, and habitats of high biodiversity. Beds with abundant branched rhodoliths ranging in size from 2 to 10 cm (longest dimension) have been found in two main types of environments: (1) gently sloping, subtidal soft bottoms with moderate wave action (wave beds; 2 to 12 m deep), and (2) relatively level bottoms in channels with tidal currents (current beds; below 12 m). Large individuals (to 11 cm) with up to 1 cm thick, densely packed branches are also found dispersed among sand and cobbles on more wave exposed shores. The relative abundance of fruticose forms and the sphericity and branch density of individual thalli are generally higher in wave beds than in current beds. Morphology within wave beds varies along gradients of water motion, with higher branch densities, more apical branching, and more branch fusions present as water motion increases. The extent to which these morphological differences represent different taxa is being evaluated. The abundance of rhodoliths in Pliocene and Pleistocene carbonate deposits and modern sediments indicates that this community has long been an important feature of nearshore environments in the Gulf. Our results suggest that measurements of a combination of morphological characters in populations of fossil rhodoliths, combined with detailed, small-scale stratigraphic analyses, may provide good estimates of paleoenvironmental conditions., Cited By (since 1996):6, Seaweeds, ,
Author: Foster, Riosmena-Rodriguez, Steller, Woelkerling
Date: 1997-01-01T00:00:00Z

Title: Response of nearshore marine assemblages to global change: A comparison of molluscan assemblages in Pleistocene and modern rhodolith beds in the southwestern Gulf of California, México,
Description: Marine life in the Gulf of California has experienced large changes in climate and sea level during the past several hundred thousand years. To evaluate the potential effects of these changes on marine mollusc species richness and similarity, modern molluscan assemblages associated with rhodolith beds in the southwestern Gulf of California were compared to their fossil counterparts from the oxygen isotope substage 5e (I.S. 5e) interglacial period, approximately 125 000 yr ago. A combined total of 219 taxa were found in I.S. 5e and modern assemblages. In general, raw and rarefied richnesses were significantly greater in I.S. 5e assemblages than in modern assemblages, and differences between assemblages suggest I.S. 5e are time-averaged deposits. Similarities between I.S. 5e and modern assemblages were lower than similarities within I.S. 5e assemblages. The results indicate that molluscan assemblages in the Gulf of California experienced some changes in taxonomic richness and composition during the environmental fluctuations of the past 125 000 yr, but not large scale taxonomic reorganization. The precise amount of taxonomic change is difficult to quantify due to time averaging. © 2002 Elsevier Science B.V. All rights reserved., Cited By (since 1996):10, CODEN: PPPYA, ,
Author: Cintra-Buenrostro, Foster, Meldahl
Date: 2002-01-01T00:00:00Z

Title: Restoration techniques for Macrocystis pyrifera (Phaeophyceae) populations at the southern limit of their distribution in Mexico,
Description: Following the 1982-83 El Nino, Macrocystis pyrifera (L.) C. Agardh, forests disappeared throughout their range in Baja California. The giant kelp forests subsequently recovered within this range except at their extreme southern limit, a region encompassing 50 km of coastline with a former giant kelp standing stock of 28,000 wet tons. Two techniques were tested to restore these forests: juvenile transplantation and seeding with sporophylls. For transplanting, juvenile M. pyrifera sporophytes were attached to Eisenia arborea stumps seasonally over a two-year period. Average survival of transplants ranged from 7% in spring to 41% in winter. After two years, the average number of basal fronds per plant increased from 2 to 64 per plant and surface fronds from 0 to 34 per plant. Average frond growth rate of the transplants ranged from 8.1 cm day -1 in summer to 10.8 cm day -1 in winter. No significant differences in growth rate were found among treatments (seasons) for the transplants, but control plants showed a seasonal variation, with higher frond growth rates in winter (13.3 cm day -1) and spring (9.3 cm day -1) and lower in summer (4.4 cm day -1). The seeding technique was tested in a fully orthogonal-block design with three factors with two levels (factors: ± sporophylls addition, ± Eisenia arborea and ± understory algae). Macrocystis pyrifera recruitment occurred only in treatments with added sporophylls. The highest recruitment occurred where all algae were removed from the bottom, followed by the treatments without understory algae but with Eisenia arborea. This results suggest that a lack of spores and the presence of understory algae were the main factors inhibiting Macrocystis pyrifera recruitment in the area. Lower sea water temperatures and high nutrient concentrations occurred in spring and high temperatures and low nutrients in summer suggesting, as in southern California, an inverse relationship between these two factors. The results suggest a combined approach of transplanting juveniles and seeding during spring would be most effective for restoring the M. pyrifera forests., Cited By (since 1996):22, CODEN: BOTNA, ,
Author: Hernández-Carmona, García, Robledo, Foster
Date: 2000-01-01T00:00:00Z

Title: Settlement and post-settlement processes limit the abundance of the geniculate coralline alga Calliarthron on subtidal walls,
Description: Cover of geniculate coralline algae is significantly greater on subtidal platforms than on vertical walls in a central California kelp forest. To determine the cause(s) of this pattern, settlement and growth of Calliarthron were compared on horizontal and vertical substrata attached to platforms or walls. Recruitment on horizontal substrata attached to reef walls indicated that spores were abundant along the walls. Densities of recruits were significantly smaller on vertical substrata attached to walls than on horizontal substrata attached to platforms, indicating that Calliarthron settlement is reduced on vertical substrata. Growth of basal crusts and the densities of fronds were also significantly greater on horizontal substrata attached to platforms than on vertical substrata attached to walls. Irradiance reaching wall surfaces was less than irradiance reaching platform surfaces. We suggest that light reaching wall surface is low enough to affect Calliarthron growth. These results indicate that the low abundance of Calliarthron on subtidal walls is a result of poor recruitment and slow growth. © 2002 Elsevier Science B.V. All rights reserved., Cited By (since 1996):13, Seaweeds, CODEN: JEMBA, ,
Author: Goldberg, Foster
Date: 2002-01-01T00:00:00Z

Title: Composition, distribution, and abundance of deep-water (>30 m) macroalgae in central California,
Description: The deep-water macroalgal assemblage was described at 14 sites off the central California coast during 1999 and 2000 from SCUBA and remotely operated vehicle sampling. The stipitate kelp Pleurophycus gardneri Setchell & Gardner, previously thought to be rare in the region, was abundant from 30 to 45 m, forming kelp beds below the well-known giant kelp forests. Macroalgae typically formed three broadly overlapping zones usually characterized by one or a few visually dominant taxa: 1) the upper "Pleurophycus zone" (30-45 m) of stipitate kelps and Desmarestia spp. with a high percent cover of corallines, low cover of uncalcified red algae, and rare green algae; 2) a middle "Maripelta zone" (40-55 m) with other uncalcified red algae and infrequent corallines and green algae; and 3) a zone (55-75 m) of infrequent patches of non-geniculate coralline algae. The green alga Palmophyllum umbracola Nelson & Ryan, not previously reported from the Northeast Pacific, was found over the entire geographical range sampled from 35 to 54 m. Year-round profiles of water column irradiance revealed unexpectedly clear water with an average K0 of 0.106·m-1. The low percent surface irradiance found at the average lower macroalgal depth limits in this study (0.56% for brown algae, 0.12% for uncalcified red algae, and 0.01% for nongenictilate coralline algae) and lack of large grazers suggest that light controls the lower distributional limits. The ubiquitous distribution, perennial nature, and similar lower depth limits of deep-water macroalgal assemblages at all sites suggest that these assemblages are a common persistent part of the benthic biota in this region., Cited By (since 1996):26 Seaweeds, CODEN: JPYLA, ,
Author: Spalding, Foster, Heine
Date: 2003-01-01T00:00:00Z

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