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Reiter, Michael A. "Development of Benthic Algal Assemblages Subjected to Differing Near-Substrate Hydrodynamic Regimes". Canadian Journal of Fisheries and Aquatic Sciences 46, n.º 8 (1 de agosto de 1989): 1375–82. http://dx.doi.org/10.1139/f89-176.
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Recent research concerning benthic algae in streams suggests that the near-substrate hydrodynamic regime may affect the composition of benthic algal assemblages. Algae from local streams were allowed to colonize laboratory flumes containing substrates of different sizes under two velocity regimes to determine whether benthic algal assemblages were affected by substrate size or hydrodynamics. While all hydrodynamic parameters except for local velocity diverged among flumes with different substrate sizes, cell counts per unit area of substrate and the relative proportions of different forms of algae remained similar overall. Much of the similarity appears to be attributable to the dominant filamentous algae. "Blooms" of one or two species were detected on occasion, but did not affect overall similarity (though they may affect local recolonization). The results, if extrapolated, suggest that hydrodynamic conditions alone may not be responsible for the variation in algal assemblages seen in the field, and that the morphological form of the alga may be more important than the species of alga when determining its response to hydrodynamic conditions.
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Williamson, Bo, Paul W. Gabrielson y Margarita Brandt. "First report of any species of the red algal order Nemaliales from mainland Ecuador: Neoizziella asiatica (Liagoraceae, Rhodophyta)". Botanica Marina 65, n.º 2 (28 de febrero de 2022): 135–39. http://dx.doi.org/10.1515/bot-2021-0092.
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Abstract The benthic marine algae of the mainland coast of Ecuador are poorly known mainly due to a lack of collections. Currently, DNA barcoding is the preferred method to identify species of benthic marine algae worldwide, as morpho-anatomical characters are inadequate to distinguish many species of macroalgae. We used the red algal barcode rbcL-3P to identify specimens collected in January 2020 from Manabí, Ecuador as Neoizziella asiatica. This is the first member of the red algal order Nemaliales to be reported from the mainland coast of Ecuador and extends the distribution of this alga by 1,100 km to the south from Panama.
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Smirnova, S. V., O. Y. Chaplygina y A. F. Luknitskaya. "Algal communities of the waterbodies of Schirmacher Oasis, East Antarctica". Arctic and Antarctic Research 66, n.º 2 (10 de julio de 2020): 198–216. http://dx.doi.org/10.30758/0555-2648-2020-66-2-198-216.
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In continental waterbodies of Antarctic oases specific algal communities are forming. The structure and dominating complex of species of this communities due to different distance from the seashore and latitude, the composition of the constituent rocks, altitude and the presence in the past of periods of contact with sea water is unique for different oases. It may vary in different waterbodies within one oasis besides.Aim of the research is to describe different types of algal communities from the continental waterbodies of Schirmacher Oasis and it’s confinement to the different types of waterbodies.Samples were collected from 173 waterbodies: 151 with stagnant water and 22 streams.During the study 64 species of Cyanoprokaryotes were found, and this group usually dominated in communities. Also 14 most frequent species of Chlorophyta, 12 most frequent species of Bacillariophyta, 6 species of desmid algae, 2 species of Xanthophyceae, 1 species of Eustigmatophyceae were noted in benthos. Usually resting stages and in one case — life cells of Golden algae (Chrysophyceae, Synurophyceae) were found in mats on the bottom of big lakes. Plankton algae in most of the waterbodies had very low abundance and diversity and were strongly influensed by trophic level. Benthic algal communities were much more diverse and abundant. Eight sustainable types of benthic algal communities were revealed in continental waterbodyes of Schirmacher Oasis. Form, colour, and species composition of bentic films and mats strongly depended on temperature, conductivity and pH of the waterbody and its depth.
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Rull Lluch, Jordi. "Marine benthic algae of Namibia". Scientia Marina 66, S3 (30 de diciembre de 2002): 5–256. http://dx.doi.org/10.3989/scimar.2002.66s35.
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Mayr, Magdalena, Jacqueline Jerney y Michael Schagerl. "Combating planktonic algae with benthic algae". Ecological Engineering 74 (enero de 2015): 310–18. http://dx.doi.org/10.1016/j.ecoleng.2014.10.034.
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Stevenson, R. J., R. Singer, D. A. Roberts y C. W. Boylen. "Patterns of Epipelic Algal Abundance with Depth, Trophic Status, and Acidity in Poorly Buffered New Hampshire Lakes". Canadian Journal of Fisheries and Aquatic Sciences 42, n.º 9 (1 de septiembre de 1985): 1501–12. http://dx.doi.org/10.1139/f85-188.
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The biovolume and species composition of algae on sediments in 20 poorly buffered New Hampshire lakes were surveyed in autumn to delineate patterns of community structure and composition with acidity and trophic status of lakes, and along depth gradients within lakes. Patterns of total algal biovolume on sediments were not strongly related to these habitat conditions because of masking by algae that probably settled from the plankton onto sediments. Biovolumes of "benthic" algae generally decreased with depth; however, weak and positive correlations between biovolumes of some benthic algal taxa and depth indicated that benthic algae had adapted to low light conditions and were perhaps facultatively heterotrophic. Decreases in diatom and increases in blue-green algal biovolumes with total phosphorus and chlorophyll a concentrations in lake water indicated that blue-green algae were better adapted for sequestering nutrients in low light environments. The variability in patterns of algal biovolume with acid neutralizing capacity (ANC) and pH indicated that algae had adapted well to different levels of ANC and pH. Biovolumes of blue-greens were negatively correlated with ANC, primarily because of the high biovolumes of various blue-green algae that occurred sporadically in lakes with ANC between 0 and 20 μeg/L and pH between 5.8 and 6.0. Diatom biovolumes generally increased with ANC and pH; however, biovolumes of several species of diatoms, including a Pinnularia, were greatest in low ANC and pH lakes. In general, Eunotia biovolumes decreased and Navicula and Pinnularia biovolumes increased with ANC and pH.
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Liao, Zhiheng, Kefu Yu, Yinghui Wang, Xueyong Huang y Lijia Xu. "Coral-algal interactions at Weizhou Island in the northern South China Sea: variations by taxa and the exacerbating impact of sediments trapped in turf algae". PeerJ 7 (13 de marzo de 2019): e6590. http://dx.doi.org/10.7717/peerj.6590.
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Competitive interactions between corals and benthic algae are increasingly frequent on degrading coral reefs, but the processes and mechanisms surrounding the interactions, as well as the exacerbating effects of sediments trapped in turf algae, are poorly described. We surveyed the frequency, proportion, and outcomes of interactions between benthic algae (turf algae and macroalgae) and 631 corals (genera: Porites, Favites, Favia, Platygyra, and Pavona) on a degenerating reef in the northern South China Sea, with a specific focus on the negative effects of algal contact on corals. Our data indicated that turf algae were the main algal competitors for each surveyed coral genus and the proportion of algal contact along the coral edges varied significantly among the coral genera and the algal types. The proportions of algal wins between corals and turf algae or macroalgae differed significantly among coral genera. Compared to macroalgae, turf algae consistently yielded more algal wins and fewer coral wins on all coral genera. Amongst the coral genera, Porites was the most easily damaged by algal competition. The proportions of turf algal wins on the coral genera increased 1.1–1.9 times in the presence of sediments. Furthermore, the proportions of algal wins on massive and encrusting corals significantly increased with the combination of sediments and turf algae as the algal type. However, the variation in proportions of algal wins between massive and encrusting corals disappeared as sediments became trapped in turf algae. Sediments bound within turf algae further induced damage to corals and reduced the competitive advantage of the different coral growth forms in their competitive interactions with adjacent turf algae.
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Davie, Alec W. y Simon M. Mitrovic. "Benthic algal biomass and assemblage changes following environmental flow releases and unregulated tributary flows downstream of a major storage". Marine and Freshwater Research 65, n.º 12 (2014): 1059. http://dx.doi.org/10.1071/mf13225.
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A large dam reducing the magnitude of flows regulates the Severn River, Australia. Environmental flows (EFs) are designed to increase the magnitude of flow and improve ecological outcomes such as reducing filamentous algal biomass and re-setting algal succession. The effectiveness of EF releases to alter benthic algal assemblages is poorly understood. We examined benthic algal biomass and assemblage structure at two cobble-dominated riffle sites downstream of Pindari Dam, before and after two EFs. Both EFs had discharges of ~11.6 m3 s–1 (velocity of ~0.9 m s–1). Neither EF reduced benthic algal biomass, and sometimes led to increases, with density of some filamentous algae increasing (Stigeoclonium and Leptolyngbya). An unregulated flow from a tributary between the two sites increased discharge to 25.2 m3 s–1 (velocity of ~1.2 m s–1), decreasing biomass and density of filamentous algae. The similarity in flow velocities between scouring and non-scouring events suggests that thresholds may exist and/or suspended sediments carried from unregulated tributaries may contribute to reduce algal biomass. Identifying velocities needed to reduce algal biomass are useful. Accordingly, EFs with flow velocities ~1.2 m s–1 may achieve this in river cobble-dominated riffle sections dominated by filamentous algae. Lower flow velocities of <0.9 m s–1 may result in no change or an increase in filamentous algae.
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Winter, Jennifer G., Peter J. Dillon, Carolyn Paterson, Ron A. Reid y Keith M. Somers. "Impacts of golf course construction and operation on headwater streams: bioassessment using benthic algae". Canadian Journal of Botany 81, n.º 8 (1 de agosto de 2003): 848–58. http://dx.doi.org/10.1139/b03-081.
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The influence of golf course operation and construction on benthic algal communities in headwater streams on the Precambrian Shield was investigated using a reference condition approach. Streams were sampled for water chemistry and epilithic benthic algae on operational golf courses, on courses under construction, and from nearby minimally impacted reference locations. Epilithic diatom community structure was different in reference streams than in operational golf course streams, the latter indicating nutrient enrichment, higher pH, and disturbance. Full counts of diatoms and soft algae revealed that there was a lower proportion of diatoms relative to other algal groups, cyanobacteria in particular, in operational golf course streams compared with samples from reference locations. Dominance by a single taxon was also significantly higher in operational golf course streams. Although differences relative to the reference streams were less marked for the streams on courses under construction, full counts of diatoms and soft algae provided evidence of disturbance and nutrient enrichment. In particular, high proportions of filamentous green algae were recorded. Overall, our results indicate that golf course land management on the Shield is associated with significant differences in the abundance of certain benthic algal taxa in headwater streams.Key words: diatoms, periphyton, biomonitoring, golf courses, canonical correspondence analysis (CCA), Precambrian Shield.
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Barott, Katie L., Beltran Rodriguez-Mueller, Merry Youle, Kristen L. Marhaver, Mark J. A. Vermeij, Jennifer E. Smith y Forest L. Rohwer. "Microbial to reef scale interactions between the reef-building coral Montastraea annularis and benthic algae". Proceedings of the Royal Society B: Biological Sciences 279, n.º 1733 (16 de noviembre de 2011): 1655–64. http://dx.doi.org/10.1098/rspb.2011.2155.
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Competition between reef-building corals and benthic algae is of key importance for reef dynamics. These interactions occur on many spatial scales, ranging from chemical to regional. Using microprobes, 16S rDNA pyrosequencing and underwater surveys, we examined the interactions between the reef-building coral Montastraea annularis and four types of benthic algae. The macroalgae Dictyota bartayresiana and Halimeda opuntia , as well as a mixed consortium of turf algae, caused hypoxia on the adjacent coral tissue. Turf algae were also associated with major shifts in the bacterial communities at the interaction zones, including more pathogens and virulence genes. In contrast to turf algae, interactions with crustose coralline algae (CCA) and M. annularis did not appear to be antagonistic at any scale. These zones were not hypoxic, the microbes were not pathogen-like and the abundance of coral–CCA interactions was positively correlated with per cent coral cover. We propose a model in which fleshy algae (i.e. some species of turf and fleshy macroalgae) alter benthic competition dynamics by stimulating bacterial respiration and promoting invasion of virulent bacteria on corals. This gives fleshy algae a competitive advantage over corals when human activities, such as overfishing and eutrophication, remove controls on algal abundance. Together, these results demonstrate the intricate connections and mechanisms that structure coral reefs.
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Millar, Alan J. K. "Marine benthic algae of Norfolk Island, South Pacific". Australian Systematic Botany 12, n.º 4 (1999): 479. http://dx.doi.org/10.1071/sb98004.
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The marine benthic algae of Norfolk Island are documented and 60 of the 236 species are illustrated. All records are fully referenced, and type localities, local distribution and notes on taxonomic and biogeographic affinities of each species are given. Of the 236 taxa, 41 species are Chlorophyta, 41 are Phaeophyta and the remainder (154) are Rhodophyta. Apart from several undescribed taxa, none is endemic to the island, although Solieria anastomosa and Dasya fruticulosa are apparently restricted to Norfolk and Lord Howe Island, the two islands presently sharing 106 species (almost half the Norfolk marine flora and one-third that of Lord Howe). Although there are some species for which Norfolk Island represents a major range extension into or within the Pacific (Dasycladus ramosus, Halicoryne wrightii, Anotrichium anthericephalum, Herposiphonia arcuata and Polysiphonia japonica), a con- siderable number of the species are shared with the Great Barrier Reef and the New South Wales coastline as well as Lord Howe Island. Major northern range extensions are recorded for the large temperate brown alga Ecklonia radiata, and possibly Phyllospora comosa and Durvillaea antarctica, although the island more typically hosts numerous tropical algae such as Trichogloea requienii and members of the green algal order Dasycladales including Halicoryne wrightii, Bornetella nitida and Neomeris annulata. As a consequence of this survey, the two rhodymeniacean species Chrysymenia ornata and C. digitata are considered to be conspecific.
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Legleiter, Carl J. y Shawn W. Hodges. "Mapping Benthic Algae and Cyanobacteria in River Channels from Aerial Photographs and Satellite Images: A Proof-of-Concept Investigation on the Buffalo National River, AR, USA". Remote Sensing 14, n.º 4 (16 de febrero de 2022): 953. http://dx.doi.org/10.3390/rs14040953.
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Although rivers are of immense practical, aesthetic, and recreational value, these aquatic habitats are particularly sensitive to environmental changes. Increasingly, changes in streamflow and water quality are resulting in blooms of bottom-attached (benthic) algae, also known as periphyton, which have become widespread in many water bodies of US national parks. Because these blooms degrade visitor experiences and threaten human and ecosystem health, improved methods of characterizing benthic algae are needed. This study evaluated the potential utility of remote sensing techniques for mapping variations in algal density in shallow, clear-flowing rivers. As part of an initial proof-of-concept investigation, field measurements of water depth and percent cover of benthic algae were collected from two reaches of the Buffalo National River along with aerial photographs and multispectral satellite images. Applying a band ratio algorithm to these data yielded reliable depth estimates, although a shallow bias and moderate level of precision were observed. Spectral distinctions among algal percent cover values ranging from 0 to 100% were subtle and became only slightly more pronounced when the data were aggregated to four ordinal levels. A bagged trees machine learning model trained using the original spectral bands and image-derived depth estimates as predictor variables was used to produce classified maps of algal density. The spatial and temporal patterns depicted in these maps were reasonable but overall classification accuracies were modest, up to 64.6%, due to a lack of spectral detail. To further advance remote sensing of benthic algae and other periphyton, future studies could adopt hyperspectral approaches and more quantitative, continuous metrics such as biomass.
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Risgaard-Petersen, Nils, Mette H. Nicolaisen, Niels Peter Revsbech y Bente Aa Lomstein. "Competition between Ammonia-Oxidizing Bacteria and Benthic Microalgae". Applied and Environmental Microbiology 70, n.º 9 (septiembre de 2004): 5528–37. http://dx.doi.org/10.1128/aem.70.9.5528-5537.2004.
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ABSTRACT The abundance, activity, and diversity of ammonia-oxidizing bacteria (AOB) were studied in prepared microcosms with and without microphytobenthic activity. In the microcosm without alga activity, both AOB abundance, estimated by real-time PCR, and potential nitrification increased during the course of the experiment. AOB present in the oxic zone of these sediments were able to fully exploit their nitrification potential because NH4 + did not limit growth. In contrast, AOB in the alga-colonized sediments reached less than 20% of their potential activity, suggesting starvation of cells. Starvation resulted in a decrease with time in the abundance of AOB as well as in nitrification potential. This decrease was correlated with an increase in alga biomass, suggesting competitive exclusion of AOB by microalgae. Induction of N limitation in the oxic zone of the alga-colonized sediments and O2 limitation of the majority of AOB in darkness were major mechanisms by which microalgae suppressed the growth and survival of AOB. The competition pressure from the algae seemed to act on the entire population of AOB, as no differences were observed by denaturing gradient gel electrophoresis of amoA fragments during the course of the experiment. Enumeration of bacteria based on 16S rRNA gene copies and d-amino acids suggested that the algae also affected other bacterial groups negatively. Our data indicate that direct competitive interaction takes place between algae and AOB and that benthic algae are superior competitors because they have higher N uptake rates and grow faster than AOB.
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Barinova, Sophia y Thomas Smith. "Algae Diversity and Ecology during a Summer Assessment of Water Quality in the Abraham Lincoln Birthplace National Historical Park, USA". Diversity 11, n.º 11 (1 de noviembre de 2019): 206. http://dx.doi.org/10.3390/d11110206.
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There were 88 species of algae and cyanobacteria observed from seven sites in the Abraham Lincoln Birthplace National Historical Park (Hodgenville, Kentucky, USA). This was the first algal investigation study in the park. There were 21 samples collected, during the summer, on 16 July 2008. Algal flora, dominated by diatoms was represented by 54 species identified (61.4% of the total), 20 species of cyanobacteria, 11 green and two charophyte algal species, and one red algal species (22.7%, 12.5%, 2.2%, and 1.1%, respectively). Benthic diatoms dominated the aquatic system with 14 species of Navicula and 12 species of Nitzschia identified, which was 15.7% and 13.5% of the total, respectively. Species tended to be site specific and 78.6% of the species were only found in two or less sites. The bioindicator methods for water quality assessment were based on species autoecology. This method was used for the first time in the USA during this study. This demonstrated that benthic and planktonic-benthic algae preferred temperate temperatures, middle-oxygenated mesotrophic waters, low-to-middle enriched by chlorides. The waters were well oxygenated, sometimes saturated by sulfides, low-alkaline, low-to-middle organic enriched, and of class 1–3 water quality with high self-purification capacity. This is very important for habitat protection and cannot be easily accomplished strictly through chemical analysis. The diversity of diatom algae not only plays a major role in the formation of algal communities and their uniqueness, but diatom algae can be a good indicator of environmental assessments and change.
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Titlyanov, Eduard A., Tamara V. Titlyanova, Mutsunori Tokeshi y Xiubao Li. "Inventory and Historical Changes in the Marine Flora of Tomioka Peninsula (Amakusa Island), Japan". Diversity 11, n.º 9 (6 de septiembre de 2019): 158. http://dx.doi.org/10.3390/d11090158.
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Intensive algal sampling was conducted from 2012 to 2017 in the Tomioka Peninsula, Amakusa-Shimoshima Island (the East China Sea, Japan), yielding a total of 293 benthic macroalgal taxa, of which 63% were red algae, 16% were brown algae, and 19% were green algae. The majority (69%) of species were previously recorded only for the tropics and/or subtropics, whereas 31% of species were recorded for temperate latitudes. Among all species of algae found from 2012 to 2017 in the Tomioka Peninsula, 163 species (56%) were newly identified species for Amakusa-Shimoshima Island, including six taxa, which were recorded in Japan for the first time. Comparison of the current data from the Amakusa-Shimoshima Island with those of nearby tropical regions suggested that the recent marine flora of the Amakusa-Shimoshima Island was more closely affiliated with the flora of a warm-temperate region. Moreover, we found that the benthic flora of the Tomioka Peninsula was significantly changed between the 1950s (Segawa & Yoshida 1961) and 2012–2017. For example, the species diversity was increased by two times, mainly at the expense of red and green algae, and the biogeographic status of the benthic flora was changed from the flora of a cold-temperate region to the flora of a warm-temperate region, which could be attributed to an introduction of red algae from the tropics of South East Asia and widespread opportunistic green algae, as well as the disappearance of cold-water brown algae. Collectively, our data suggested that these changes were driven by the global warming effect on the ocean.
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Pang, Qian, Guang Hu, Kun Jiao, Xiucheng Tan, Hong Liu, Yuehao Ye, Shun Yan y Dongfang Zhao. "Characteristics of organic pores and composition of bio-precursors in the Wufeng and Longmaxi Formation shales, Southern Sichuan Basin, China". Energy Exploration & Exploitation 36, n.º 4 (17 de enero de 2018): 645–64. http://dx.doi.org/10.1177/0144598717753166.
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Bio-precursors of organic matter, referring to formerly living precursors, can influence content and distribution of organic pores significantly. However, insufficient attention has been paid in previous studies. To research the impact of bio-precursors of organic matter on shale organic pores, we conducted palynology and thin section analysis, total organic carbon analysis, and N2 gas absorption experiments on the Wufeng and Longmaxi Formations shales and kerogen samples from the Shuanghe outcrop section in southern Sichuan Basin, China. Generally, there are three bio-precursor assemblages being developed from bottom to top in the Wufeng and Longmaxi Formation, namely benthic algae, benthic–planktonic algae, and planktonic algae assemblages. Porosity in kerogen contributes greatly to shale porosity, accounting for 13 − 53% of total porosity. The total porosity and mesopore volume of samples (kerogen and shale) dominated by benthic algae are higher than those by planktonic algae. Pore size distributions of kerogen samples containing mainly benthic algae and planktonic algae are unimodal and multimodal type, respectively, when the pore diameter is larger than 5 nm. The different features between benthic and planktonic algae assemblages could be attributed to their different hydrocarbon generation potential and biological structure. Smaller fractal dimension of pores in kerogen samples mainly containing planktonic algae suggested that the planktonic algae are responsible for smoother pores in shales.
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Easton, Erin E., Carlos F. Gaymer, Alan M. Friedlander y James J. Herlan. "Effects of herbivores, wave exposure and depth on benthic coral communities of the Easter Island ecoregion". Marine and Freshwater Research 69, n.º 6 (2018): 997. http://dx.doi.org/10.1071/mf17064.
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The Easter Island ecoregion includes Rapa Nui (Easter Island; RN), with a human population of ~5600, and the uninhabited Salas y Gómez (SyG). Although the culture and terrestrial ecology of RN have been well studied, we know little about the marine environment of these islands, particularly the interplay among herbivores, algae, and corals, and how coral reef communities differ between islands, by wave energy exposure, and between depths. To address the potential roles of herbivores, wave-energy exposure, and depth on the sessile benthic communities, we examined herbivorous fish biomass, sea urchin (Diadema savignyi) density, and algal and coral cover to identify patterns and relationships among these groups. We found significant differences between islands. For example, turf and macroalgae were nearly absent from SyG, whereas D. savignyi density and Kyphosus sandwicensis biomass were ~28- and ~3-fold greater respectively at SyG. Benthic cover of coral and algae and density of D. savignyi significantly differed among levels of wave exposure, especially between wave-protected stations and semi-exposed and exposed stations. Likewise, community structure significantly differed at protected stations. Concordant patterns between herbivores and algae were observed. Therefore, herbivores and wave energy likely play important roles in structuring these benthic communities, especially for algal groups.
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Barrientos, Guillermo, Andrés Iroumé, Héctor Ulloa, Silvia Basualto y Oscar Parra. "Abundance of Benthic Algae in Forestry Watersheds and the Associated Forest Cover Factors". Forests 13, n.º 3 (25 de febrero de 2022): 378. http://dx.doi.org/10.3390/f13030378.
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We analyzed the abundance of benthic algae in nine forested headwater watersheds in south-central Chile to study the relationship between the variability of the abundance of benthic algae and physicochemical parameters and forest cover factors. Between 10 November 2015 and 18 August 2016, we sampled benthic algae and physicochemical parameters in the streams and characterized forest cover factors in each of the study watersheds. We found that physicochemical parameters and forest cover factors have contrasting effects on abundance. More specifically, the following observations were made: (1) maximum diversity and abundance occurred in watersheds covered with Pinus radiata, (2) seasonal ranks did not influence the abundance of benthic algae, (3) benthic algae abundance is controlled by rank dissimilarities in type of vegetation, solar radiation, volume, density age, canopy openness, native forest area, plantation area and harvested area, and (4) regression analysis of genera exhibited significant variability with physicochemical parameters (water temperature, pH, ammonium, nitrate, phosphorus, solar radiation) and forest cover factors (volume, density, age, native forest area, plantation area and harvested area); however, these effects were not seen in all genera. Factors related to the benthic algae compartment showed the highest sensitivity to forest cover, emphasizing their value as biological indicators of water quality and stream ecological integrity.
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Hoek, C. y K. Lüning. "“Biogeography of marine benthic algae”". Helgoländer Meeresuntersuchungen 42, n.º 2 (junio de 1988): 131–32. http://dx.doi.org/10.1007/bf02366039.
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Ariesyady, Herto Dwi y Indah Yusliga Sari Purba. "The Determination of Algae Group as Bioindicator of Water Quality Change Affected by Mercury Release from Artisanal Small-Scale Gold Mining (ASGM)". Journal of Engineering and Technological Sciences 54, n.º 4 (18 de julio de 2022): 220414. http://dx.doi.org/10.5614/j.eng.technol.sci.2022.54.4.14.
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Artisanal small scale gold mining (ASGM) practices typically use mercury for amalgamation. Near water environments this can degrade water quality and aquatic biota, including algae. Changes in algal communities can reflect water environment disturbance. The aim of this study was to determine if algae can be used as bioindicator of river water quality impacted by ASGM activities. The research was conducted from July to October 2018 at thirty sampling sites along rivers near ASGM areas in several regencies of Indonesia. Composite samples of water and sediment were collected. A plankton net and brushing methods were used to collect planktonic and benthic algae, respectively. The physicochemical parameters of the water and the sediment as well as the dominant algae genera were analyzed statistically with principal component analysis. The results showed that the total mercury concentration in the water ranged from <0.04 to 20 µg.L-1, while in the sediment the maximum value was 13,500 µg.kg-1. The total mercury content in the sediment was negatively correlated with the dominant benthic Navicula at a significance level of p < 0.05. This means that a low density of benthic Navicula can be proposed as a bioindicator of water quality, indicating the increase of mercury pollution in sediment.
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Cao, Ping, Fengran Xu, Shilin Gao, Baiyin Baoligao, Xiangdong Li, Xiangpeng Mu, Ana Mendes y Xu Shang. "Experimental Study on the Impact of Pulsed Flow Velocity on the Scouring of Benthic Algae from a Mountainous River". Water 14, n.º 19 (6 de octubre de 2022): 3150. http://dx.doi.org/10.3390/w14193150.
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The decrease in periodic scouring of pulsed flows in regulated rivers can result in algal communities dominated by filamentous algae, not available as food sources for fish and macroinvertebrates. To study the pulsed flow velocity required to scour benthic algae from natural river beds, the removal effects on the algal biomass and resistances of different species were tested in a laboratory flume at different velocities of 0.8, 1.1, 1.4, 1.7, and 2.0 m/s. The removal of total algal biomass showed a significant positive relationship with increasing velocities, which reached 22% at 2.0 m/s. The biomass removal of green algae and diatoms was higher than that of blue–green algae. The flow velocity at 1.4 m/s had a clear removal effect on filamentous algae. The velocity higher than 1.7 m/s caused a significant increase in the removal percentage of total biomass dominated by diatoms and blue–green algae. To reduce the filamentous algae and retain the diatoms and blue–green algae, a range of near bed flow velocity was suggested to be 1.4–1.7 m/s. This range could serve as a reference for required pulsed flow velocity to reduce the growth of excessive or nuisance periphyton.
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Rasha Hamdy, Rasha Hamdy. "Diversity and Distribution of Polychaetes Associated with Macroalgae along the Alexandria Coast, Egypt". journal of king abdulaziz university marine science 28, n.º 2 (4 de febrero de 2018): 67–79. http://dx.doi.org/10.4197/mar.28-2.5.
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The relationship between benthic macroalgae and associated polychaetes was studied monthly from October 2014 to October 2015 along the Alexandria coast, Egypt. A total of 56 polychaete species were found among 28 macroalgal species, which belonging to green, brown and red algae. The red algae hosted pronouncedly higher number of polychaete species than the brown and green algae, particularly during winter and spring, while green algae were associated with higher number of polychaete species in January, April, August and October 2015. In contrast, the average count of polychaete individuals associated with the green algae was higher in winter and autumn than that recorded with the red algae, while low with both red and green algae in spring and summer, and very poor within the brown algae. The present study revealed that the structure of algal species my affect the diversity and abundance of the associated polychaetes and the diversity of these worms varied among the hosting algal species.
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Lim, An Suk y Hae Jin Jeong. "Benthic dinoflagellates in Korean waters". ALGAE 36, n.º 2 (17 de junio de 2021): 91–109. http://dx.doi.org/10.4490/algae.2021.36.5.31.
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Sarkar, Suman, Amit K. Ghosh y Madhav Kumar. "Recognition of algal rich facies from the Umlatdoh Limestone of Shella Formation, Jaintia Group, Meghalaya". Journal of Palaeosciences 60, n.º (1-2) (31 de diciembre de 2011): 315–21. http://dx.doi.org/10.54991/jop.2011.178.
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The carbonate rocks of the Shella Formation (Middle Eocene) belonging to the Jaintia Group in the Jaintia Hills of Meghalaya are represented by two sandstone units in alternation with three limestone units, viz. Lakadong Limestone, Umlatdoh Limestone and Prang Limestone respectively in chronological order. Umlatdoh Limestone, the middle limestone unit of Shella Formation is conformably underlain by the Lakadong Sandstone and overlain by Narpuh Sandstone. Samples from the Umlatdoh Limestone were collected from the outcrop on the Jowai-Badarpur Road, about 1 km southwest of Lumshnong. Calcareous algae have been recovered from four samples and two distinct facies have been recognized. One of the facies is dominated by non-geniculate coralline red algae and benthic foraminifera. The non-geniculate corallines are represented by Lithothamnion and Mesophyllum (Family Hapalidiaceae), Lithoporella (Family Corallinaceae) and Sporolithon (Family Sporolithaceae). The other facies is rich in calcareous green algae along with benthic foraminifera. The green algal genera belong to families Dasycladaceae, Udoteaceae and Halimedaceae. Previously, a green algal assemblage was recorded from the Umlatdoh Limestone Member of Shella Formation exposed in the low lying hills between Sutnga and Litang valleys of Jaintia Hills. However, this is the first report on the occurrence of non-geniculate coralline red algae from the Umlatdoh Limestone Member of the Shella Formation. Based on the algal-foraminiferal assemblages, interpretation has been made on the palaeoenvironment and palaeobathymetry.
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Sun, Longfei, Leixiang Wu, Xiaobo Liu, Wei Huang, Dayu Zhu, Zhuowei Wang, Ronghao Guan y Xingchen Liu. "Reducing the Risk of Benthic Algae Outbreaks by Regulating the Flow Velocity in a Simulated South–North Water Diversion Open Channel". International Journal of Environmental Research and Public Health 20, n.º 4 (17 de febrero de 2023): 3564. http://dx.doi.org/10.3390/ijerph20043564.
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The reduction in open-channel flow velocity due to China’s South-to-North Water Diversion Project (SNP) increases the risk of benthic algal community blooms resulting in drinking water safety issues. Consequently, it has attracted attention from all walks of life. However, regulatory measures to mitigate the risk of algal blooms and the main risk-causing factors are unclear. This study simulated the river ecosystem of the SNP channel through water diversion. Simulated gradient-increasing river flow velocity affects environmental factors and benthic algal alterations, and can be used to explore the feasibility of regulating the flow velocity to reduce the risk of algal blooms. We found that the algal biomasses in the velocity environments of 0.211 and 0.418 m/s decreased by 30.19% and 39.88%, respectively. Community structure alterations from diatoms to filamentous green algae were 75.56% and 87.53%, respectively. We observed significant differences in biodiversity, especially in terms of richness and evenness. The α diversity index of a species is influenced by physical and chemical environmental factors (especially flow velocity). Our study revealed that flow velocity is the main factor affecting the growth and outbreak of benthic algae. The risk of algal blooms in open channels can be effectively mitigated by regulating the flow velocity. This provides a theoretical basis for ensuring the water safety of large-scale water conservancy projects.
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Lee, Kyeong-Tae, Hye-Mi Lee, Thatchaneshkanth Subramaniam, Hyun-Sung Yang, Sang Rul Park, Chang-Keun Kang, Shashank Keshavmurthy y Kwang-Sik Choi. "Dominance of the scleractinian coral Alveopora japonica in the barren subtidal hard bottom of high-latitude Jeju Island off the south coast of Korea assessed by high-resolution underwater images". PLOS ONE 17, n.º 11 (4 de noviembre de 2022): e0275244. http://dx.doi.org/10.1371/journal.pone.0275244.
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Coastal benthic communities in temperate regions have been influenced by climate change, including increasing sea-surface temperature. Nevertheless, scleractinian coral Alveopora japonica Eguchi, 1968, is thriving in shallow subtidal hard bottoms around Jeju Island, off the southern coast of Korea. The presence of this corals has negatively impacted subtidal kelp populations in Jeju Island. However, there is no study to document how the presence or absence of this coral relates to other benthic communities. This study investigated the benthos in three shallow subtidal sites (Shinheung (SH), Bukchon (BC), and Seongsan (SS)) in northern Jeju using underwater photography. Macro-benthic organisms appearing on a 1 × 20 m line transect installed at depths of 5, 10, and 15 m at each site were analyzed. Results showed that of the three sites investigated, A. japonica colonies were most abundant at BC, accounting for 45.9% and 72.8% of the total transect area at 10 m and 15 m, respectively. At SS, A. japonica occupied 15.3% of the total area at 15 m and less than 1% at 5 m and 10 m. The same at SH accounted for 10% of the total area at 5 m, and less than 1% at 10 m and 15 m. Dead and bleached colonies accounted for 1.2–11.5% and 1.8–5.7%, respectively, at 5, 10, and 15 m at three sites. At SS, canopy-forming brown algae Ecklonia cava and Sargassum spp. accounted for 20.2 and 24.3% of the total transect area, respectively, at 5 m depth. In contrast, the percent cover of E. cava and Sargassum spp. at SH and BC ranged from 0.1 to 1.8%, respectively. Moreover, non-geniculate coralline algae dominated the subtidal substrate at SH, ranging between 60.2 and 69% at 15 and 10 m. The low cover of A. japonica in SS (at 5 m) coincided with a high percent cover of canopy-forming brown algae. However, canopy-forming brown algae were rare at all depths at SH and BC and were dominated instead by coralline algae and the scleractinian corals. This study, by utilizing a non-destructive method, provides a baseline qualitative and quantitative information for understanding the site and depth-dependent distribution of A. japonica and algal populations, which is important to understand climate change related changes in benthic communities in Jeju and elsewhere.
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Yasuno, Natsuru, Yuki Chiba, Yasufumi Fujimoto, Kentaro Shindo, Tetsuo Shimada, Shuichi Shikano y Eisuke Kikuchi. "Zoobenthos are minor dietary components of small omnivorous fishes in a shallow eutrophic lake". Marine and Freshwater Research 67, n.º 10 (2016): 1562. http://dx.doi.org/10.1071/mf15156.
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We examined whether small omnivorous fishes (smaller than ~100mm long) integrate littoral, pelagic and benthic pathways in a shallow, eutrophic lake (Lake Izunuma, Japan). The surface of the lake was covered by a dense vegetation of floating-leaved macrophytes, and small species dominated the icthyofauna. We determined the δ13C and δ15N ratios of five dominant species of small omnivorous fishes. Using a stable isotope analysis in the R mixing model, we determined the possible contribution of three potential food sources (epiphytic algae, zooplankton and zoobenthos (larval chironomids)) to omnivorous fish tissue compositions. Four omnivorous fishes (Gnathopogon elongatus elongatus, Pseudorasbora parva, Biwia zezera and Tridentiger obscurus) subsisted largely on epiphytic algae and zooplankton, whereas zoobenthos contributed little to their diets. Acheilognathus rhombeus subsisted mostly on epiphytic algae. Thus, in this shallow, eutrophic lake, omnivorous fishes incorporated both littoral and pelagic production into the food web, but rarely benthic production. The dominant benthic chironomid larvae often burrow several centimetres into the sediment, and the low dietary contribution of zoobenthos to small fishes may be due to inefficiency at foraging on buried benthos associated with fish body size.
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Wynne, Michael J. "A checklist of the benthic marine algae of the Northern Arabian Sea coast of the Sultanate of Oman". Botanica Marina 61, n.º 5 (25 de septiembre de 2018): 481–98. http://dx.doi.org/10.1515/bot-2018-0035.
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Abstract An updated checklist of the benthic marine algae (seaweeds) of the Northern Arabian Sea coast of the Sultanate of Oman is presented, with a total of 402 taxa, consisting of 75 taxa of brown algae (Phaeophyceae), 238 taxa of red algae (Rhodophyta), and 89 taxa of green algae (Chlorophyta). Obsolete names and taxonomic synonyms as well as information on mis-identified names are provided. The classification in many instances reflects new ideas derived from the results of molecular-based phylogenetics. A total of 18 taxa of benthic marine algae are newly reported for Oman.
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Lu, Chunrong, Qi Zhang, Qinyu Huang, Shuying Wang, Xiao Qin, Tianfei Ren, Rufeng Xie y Hongfei Su. "Significant Shifts in Microbial Communities Associated with Scleractinian Corals in Response to Algae Overgrowth". Microorganisms 10, n.º 11 (5 de noviembre de 2022): 2196. http://dx.doi.org/10.3390/microorganisms10112196.
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Microbes play a key role in reef dynamics, mediating the competition between scleractinian corals and benthic algae; however, major shifts in bacterial communities among coral species in response to increases in the abundance of algae are not well understood. We investigated the taxonomic composition of coral-associated microbial communities under algae-overgrowth conditions using 16S rRNA gene sequencing. The results showed that non-algal (i.e., healthy) tissue (HH) had lower bacterial abundance and diversity than tissue collected from the coral–algae interface boundary (HA) and areas of algae growth (AA). Specifically, the HA and AA samples had higher relative abundances of Saprospiraceae, Rhodobacteraceae, and Alteromonadaceae. Compared with Platygyra sp. and Montipora sp., the physiological response of Pocillopora sp. was more intense under algae-induced stress based on microbial gene function prediction. Our results indicate that algal pressure can significantly alter the microbial community structure and function of coral ecosystems. Our data thus provide new insight into the relationship between corals and their microbiome under environmental stress.
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Payri, Claude E. y Antoine D. R. N'Yeurt. "A Revised Checklist of Polynesian Benthic Marine Algae". Australian Systematic Botany 10, n.º 6 (1997): 867. http://dx.doi.org/10.1071/sb96009.
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A revised checklist of 425 taxa of benthic marine algae is provided for the French Polynesian region, including the Society Islands, Tuamotu Archipelago, Marquesas Islands and Austral Islands. The list comprises 117 Cyanophyceae, 42 Phaeophyceae, 96 Chlorophyceae and 170 Rhodophyceae, representing 79 new additions to the last checklist a decade earlier. Included are all previously published records and some yet unpublished additions, with the systematic arrangement and nomenclature updated. The flora of Tahiti and its adjacent islands is quite well known, whereas the one from Marquesas, Austral and Gambier Islands have yet to be adequately examined. Also, such algal groups as the crustose Corallinaceae are still poorly studied.
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Soe-Htun, U., Soe Pa Pa Kyaw, Mya Kyawt Wai, Jar San, SeinMoh Moh Khaing y Chaw Thiri Pyae Phyo Aye. "A review on the seaweed resources of Myanmar". Journal of Aquaculture and Marine Biology 10, n.º 4 (2021): 152–66. http://dx.doi.org/10.15406/jamb.2021.10.00317.
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A total of 261species of marine benthic algae under 121genera,comprising 72 taxa belonging to 26 genera of Chlorophyta, 45 taxa belonging to 18 genera of Phaeophyta and 144 taxa belonging to 77 genera of Rhodophyta growing along the Tanintharyi Coastal Zone, Deltaic Coastal Zone and Rakhine Coastal Zone, were recorded. In general, diversity ratios of seaweeds occur in 3 Coastal Zones is 3:1:4 between the Tanintharyi Coastal Zone (146 taxa), Deltaic Coastal Zone (53 taxa) and Rakhine Coastal Zone (224 taxa).Among these, 89 species of marine benthic algae, including 25 taxa of green, 9 taxa of brown and 55 taxa of red algae, were newly recorded from Myanmar waters. The latitudinal distribution of marine benthic algae along the Myanmar Coastal Zones reveals 25 species of marine benthic algae which uniquely occur in low lattitute in the Tanintharyi Coastal Zone and 111 species which exclusively predominate in high lattitutein the Rakhine Coastal Zone. Monostroma, Ulva, Caulerpa and Codium of Chlorophyta, Dictyota, Spatoglossum, Hormophysa, Turbinaria and Sargassum of Phaeophyta and Phycocalidia, Dermonema, Gelidiella, Halymenia, Solieria, Hypnea, Gracilaria,Gracilariopsis, Hydopuntia, Catenella and Acanthophora of Rhodophyta could be considered as of dependable natural resources of Myanmar to produce the sea-vegetables and phycocolloids. Mariculture of some economically important marine red algae such as Gracilaria spp., Hydopuntia spp., Catenella spp. And Kappaphycus alvarezii was described. Current status and prospects of phycocolloid industries producing alginate, agar-agar and carrageenansfrom raw materials of seaweeds of Myanmar were discussed. Checklist, distribution and conservation of marine benthic algae were briefly presented.
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Walsh, Kevin, J. Matthew Haggerty, Michael P. Doane, John J. Hansen, Megan M. Morris, Ana Paula B. Moreira, Louisi de Oliveira et al. "Aura-biomes are present in the water layer above coral reef benthic macro-organisms". PeerJ 5 (15 de agosto de 2017): e3666. http://dx.doi.org/10.7717/peerj.3666.
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As coral reef habitats decline worldwide, some reefs are transitioning from coral- to algal-dominated benthos with the exact cause for this shift remaining elusive. Increases in the abundance of microbes in the water column has been correlated with an increase in coral disease and reduction in coral cover. Here we investigated how multiple reef organisms influence microbial communities in the surrounding water column. Our study consisted of a field assessment of microbial communities above replicate patches dominated by a single macro-organism. Metagenomes were constructed from 20 L of water above distinct macro-organisms, including (1) the coral Mussismilia braziliensis, (2) fleshy macroalgae (Stypopodium, Dictota and Canistrocarpus), (3) turf algae, and (4) the zoanthid Palythoa caribaeorum and were compared to the water microbes collected 3 m above the reef. Microbial genera and functional potential were annotated using MG-RAST and showed that the dominant benthic macro-organisms influence the taxa and functions of microbes in the water column surrounding them, developing a specific “aura-biome”. The coral aura-biome reflected the open water column, and was associated with Synechococcus and functions suggesting oligotrophic growth, while the fleshy macroalgae aura-biome was associated with Ruegeria, Pseudomonas, and microbial functions suggesting low oxygen conditions. The turf algae aura-biome was associated with Vibrio, Flavobacterium, and functions suggesting pathogenic activity, while zoanthids were associated with Alteromonas and functions suggesting a stressful environment. Because each benthic organism has a distinct aura-biome, a change in benthic cover will change the microbial community of the water, which may lead to either the stimulation or suppression of the recruitment of benthic organisms.
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Karcher, Denis B., Florian Roth, Susana Carvalho, Yusuf C. El-Khaled, Arjen Tilstra, Benjamin Kürten, Ulrich Struck, Burton H. Jones y Christian Wild. "Nitrogen eutrophication particularly promotes turf algae in coral reefs of the central Red Sea". PeerJ 8 (2 de abril de 2020): e8737. http://dx.doi.org/10.7717/peerj.8737.
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While various sources increasingly release nutrients to the Red Sea, knowledge about their effects on benthic coral reef communities is scarce. Here, we provide the first comparative assessment of the response of all major benthic groups (hard and soft corals, turf algae and reef sands—together accounting for 80% of the benthic reef community) to in-situ eutrophication in a central Red Sea coral reef. For 8 weeks, dissolved inorganic nitrogen (DIN) concentrations were experimentally increased 3-fold above environmental background concentrations around natural benthic reef communities using a slow release fertilizer with 15% total nitrogen (N) content. We investigated which major functional groups took up the available N, and how this changed organic carbon (Corg) and N contents using elemental and stable isotope measurements. Findings revealed that hard corals (in their tissue), soft corals and turf algae incorporated fertilizer N as indicated by significant increases in δ15N by 8%, 27% and 28%, respectively. Among the investigated groups, Corg content significantly increased in sediments (+24%) and in turf algae (+33%). Altogether, this suggests that among the benthic organisms only turf algae were limited by N availability and thus benefited most from N addition. Thereby, based on higher Corg content, turf algae potentially gained competitive advantage over, for example, hard corals. Local management should, thus, particularly address DIN eutrophication by coastal development and consider the role of turf algae as potential bioindicator for eutrophication.
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Casey, Jordan M., Tracy D. Ainsworth, J. Howard Choat y Sean R. Connolly. "Farming behaviour of reef fishes increases the prevalence of coral disease associated microbes and black band disease". Proceedings of the Royal Society B: Biological Sciences 281, n.º 1788 (7 de agosto de 2014): 20141032. http://dx.doi.org/10.1098/rspb.2014.1032.
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Microbial community structure on coral reefs is strongly influenced by coral–algae interactions; however, the extent to which this influence is mediated by fishes is unknown. By excluding fleshy macroalgae, cultivating palatable filamentous algae and engaging in frequent aggression to protect resources, territorial damselfish (f. Pomacentridae), such as Stegastes , mediate macro-benthic dynamics on coral reefs and may significantly influence microbial communities. To elucidate how Stegastes apicalis and Stegastes nigricans may alter benthic microbial assemblages and coral health, we determined the benthic community composition (epilithic algal matrix and prokaryotes) and coral disease prevalence inside and outside of damselfish territories in the Great Barrier Reef, Australia. 16S rDNA sequencing revealed distinct bacterial communities associated with turf algae and a two to three times greater relative abundance of phylotypes with high sequence similarity to potential coral pathogens inside Stegastes 's territories. These potentially pathogenic phylotypes (totalling 30.04% of the community) were found to have high sequence similarity to those amplified from black band disease (BBD) and disease affected corals worldwide. Disease surveys further revealed a significantly higher occurrence of BBD inside S. nigricans 's territories. These findings demonstrate the first link between fish behaviour, reservoirs of potential coral disease pathogens and the prevalence of coral disease.
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Gouvea, R. C., M. E. Castelo Branco, P. L. Santos y V. A. Gouvea. "Accumulation of210Po by benthic marine algae". Environmental Technology Letters 9, n.º 8 (agosto de 1988): 891–97. http://dx.doi.org/10.1080/09593338809384645.
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Gutow, L., L. Giménez, K. Boos y R. Saborowski. "Rapid changes in the epifaunal community after detachment of buoyant benthic macroalgae". Journal of the Marine Biological Association of the United Kingdom 89, n.º 2 (17 de noviembre de 2008): 323–28. http://dx.doi.org/10.1017/s0025315408002658.
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Rafting on floating macroalgae is a common dispersal mechanism of marine benthic invertebrates. Most benthic macroalgae are inhabited by diverse epifaunal communities but not all organisms may be adapted to live on floating algae. In particular, knowledge about the immediate effects of algal detachment on the associated biota is limited. Herein, we studied the composition of the communities of mobile invertebrates on benthic thalli of Ascophyllum nodosum and compared it with detached thalli that had floated for short periods. The community of the mobile invertebrates changed significantly within the first minute after detachment of the algae and showed decreased diversity and a tendency towards reduced abundances in most taxa. However, during the subsequent two hours of floating at the sea surface the species composition did not change further. A comparison of the size-spectra of the gastropod Littorina obtusata from attached and detached algae did not reveal differential migratory activity among size-classes of these gastropods. Most of the species encountered in this study are common rafters in coastal and offshore waters, which are well capable of holding onto floating seaweeds. Therefore, our results indicate that the animals actively abandoned the macroalgae immediately after detachment. A benefit of this behaviour may be to avoid increased predation risk in the open water. The fact that individuals remain associated with their algal host after detachment indicates the importance of rafting dispersal for a great variety of phytal species that might lead to range expansion and regional population persistence through metapopulation effects.
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Kraft, Gerald T. "Algae of Australia: Marine benthic algae of north-western Australia 2. Red algae". Phycologia 58, n.º 2 (6 de febrero de 2019): 225–27. http://dx.doi.org/10.1080/00318884.2018.1551025.
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Rovellini, Alberto, Matthew R. Dunn, Elizabeth A. Fulton, Lisa Woods, Jamaluddin Jompa, Abdul Haris y James J. Bell. "Interannual variability and decadal stability of benthic organisms on an Indonesian coral reef". Journal of the Marine Biological Association of the United Kingdom 101, n.º 2 (marzo de 2021): 221–31. http://dx.doi.org/10.1017/s0025315421000291.
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AbstractThe availability of colonizable substrate is an important driver of the temporal dynamics of sessile invertebrates on coral reefs. Increased dominance of algae and, in some cases, sponges has been documented on many coral reefs around the world, but how these organisms benefit from non-colonized substrate on the reef is unclear. In this study, we described the temporal dynamics of benthic organisms on an Indonesian coral reef across two time periods between 2006 and 2017 (2006–2008 and 2014–2017), and investigated the effects of colonizable substrate on benthic cover of coral reef organisms at subsequent sampling events. In contrast with other Indonesian reefs where corals have been declining, corals were dominant and stable over time at this location (mean ± SE percentage cover 42.7 ± 1.9%). Percentage cover of turf algae and sponges showed larger interannual variability than corals and crustose coralline algae (CCA) (P < 0.001), indicating that these groups are more dynamic over short temporal scales. Bare substrate was a good predictor of turf cover in the following year (mean effect 0.2, 95% CI: 0–0.4). Algal cover combined with bare space was a good predictor of CCA cover the following year generally, and of sponge cover the following year but only at one of the three sites. These results indicate that turf algae on some Indonesian reefs can rapidly occupy free space when this becomes available, and that other benthic groups are probably not limited by the availability of bare substrate, but may overgrow already fouled substrates.
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Klochkova, N. G., T. A. Klochkova y A. V. Klimova. "MARINE BENTHIC ALGAE FROM COMMANDER ISLANDS (REVISION 2021). II. RHODOPHYTA". Bulletin оf Kamchatka State Technical University, n.º 55 (2021): 41–72. http://dx.doi.org/10.17217/2079-0333-2021-55-41-72.
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We present results of revision based on our personal data and reports published from 1889 to 2020 on the red algal species composition from the Commander Islands. The general list includes 150 species. Six species are reported for the first time, including Phymatolithon lamii, Neoabbottiella valentinae, Callophyllis beringensis, Kallymeniopsis verrucosa, Velatocarpus kurilensis, and Mazzaella hemisphaerica. These species are illustrated by photographs of samples collected by us from Bering Island in September 2020. Another 15 red algal species reported from this area by different authors we attributed by us to doubtful and incorrectly identified taxa. The list of valid species is organized similarly to that in our recent paper on flora of the green and brown algae from the Commander Islands [Klochkova et al., 2020]. In the list, we cite papers containing information on species records from this area. For all species, information on their distribution frequency, depth, and some ecological and biological features are provided. It is shown that in contrast to many other regions of the Russian Far East, the Commander Islands are well studied from phycological and floristic aspects. This is due to seasonal and year-round investigations carried out in this region in different time periods, a thorough diving survey on the coastal area and more complete study on microepiphyte species composition, including microscopic red algae.
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Swierts, Thomas y Mark JA Vermeij. "Competitive interactions between corals and turf algae depend on coral colony form". PeerJ 4 (10 de mayo de 2016): e1984. http://dx.doi.org/10.7717/peerj.1984.
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Turf algae are becoming more abundant on coral reefs worldwide, but their effects on other benthic organisms remain poorly described. To describe the general characteristics of competitive interactions between corals and turf algae, we determined the occurrence and outcomes of coral–turf algal interactions among different coral growth forms (branching, upright, massive, encrusting, plating, and solitary) on a shallow reef in Vietnam. In total, the amount of turf algal interaction, i.e., the proportion of the coral boundary directly bordering turf algae, was quantified for 1,276 coral colonies belonging to 27 genera and the putative outcome of each interaction was noted. The amount of turf algal interaction and the outcome of these interactions differed predictably among the six growth forms. Encrusting corals interacted most often with turf algae, but also competed most successfully against turf algae. The opposite was observed for branching corals, which rarely interacted with turf algae and rarely won these competitive interactions. Including all other growth forms, a positive relationship was found between the amount of competitive interactions with neighboring turf algae and the percentage of such interaction won by the coral. This growth form dependent ability to outcompete turf algae was not only observed among coral species, but also among different growth forms in morphologically plastic coral genera (Acropora, Favia, Favites, Montastrea, Montipora, Porites) illustrating the general nature of this relationship.
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Journal, Baghdad Science. "Community Structure of Benthic Algae in a Lotic Ecosystem, Karbala Province-Iraq". Baghdad Science Journal 14, n.º 4 (3 de diciembre de 2017): 692–706. http://dx.doi.org/10.21123/bsj.14.4.692-706.
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This study focused on benthic algae (epipelic and attached algae on concrete lining stream) in Bani-Hassan stream in Holly Karbala, Iraq. The qualitative and quantitative studies of benthic algae were done by collecting 240 samples from five sites in the study area for the period from December 2012 to November 2013. Also, the environmental variables of the stream were examined in term of temporary and spatial. The results showed that the stream was alkaline, hard, oligohaline and a well aerated. The total nitrogen to the total phosphorus (TN: TP) ratio indicates nitrogen limitation. 129 species of benthic algae belonging to 57 genera were identified. Bacillariophyceae (diatoms) was the predominant taxon (95 species) followed by Chlorophyceae (16 species), Cyanophyceae (14 species), Euglenophyceae (3 species) and Pyrophyceae (one species). Some genera were found throughout the study period: Nitzschia, Navicula, Cymbella, Gomphonema, Surirella, Cocconeis, Aulacoseira, Oscillatoria, Lyngbya, Spirulina, and ? Scenedesmus. Site 3 recorded the highest total number of algae in spring 2013, and the lowest total number was at site 5 in Autumn 2013. The chlorophyll-a concentration did not match the total number of algae.
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Elías Ilosvay, Xochitl E., Johanna Segovia, Sebastian Ferse, Walter Ernesto Elias y Christian Wild. "Rapid relative increase of crustose coralline algae following herbivore exclusion in a reef of El Salvador". PeerJ 9 (11 de febrero de 2021): e10696. http://dx.doi.org/10.7717/peerj.10696.
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The Eastern Tropical Pacific (ETP) is one of the most isolated and least studied regions in the world. This particularly applies to the coast of El Salvador, where the only reef between Guatemala and Nicaragua, called Los Cóbanos reef, is located. There is very little published information about the reef’s biodiversity, and to our knowledge, no research on its ecology and responses to anthropogenic impacts, such as overfishing, has been conducted. The present study, therefore, described the benthic community of Los Cóbanos reef, El Salvador, using the Line-Point-Intercept-Transect method and investigated changes in the benthic community following the exclusion of piscine macroherbivores over a period of seven weeks. Results showed high benthic algae cover (up to 98%), dominated by turf and green algae, and low coral cover (0–4%). Porites lobata was the only hermatypic coral species found during the surveys. Surprisingly, crustose coralline algae (CCA) showed a remarkable total cover increase by 58%, while turf algae cover decreased by 82%, in experimental plots after seven weeks of piscine macroherbivore exclusion. These findings apparently contradict the results of most previous similar studies. While it was not possible to ascertain the exact mechanisms leading to these drastic community changes, the most likely explanation is grazing on turf by small grazing macroherbivores that had access to the cages during the experiment and clearing of CCA initially covered by epiphytes and sediments. A higher CCA cover would promote the succesful settlement by corals and prevent further erosion of the reef framework. Therefore it is crucial to better understand algal dynamics, herbivory, and implications of overfishing at Los Cóbanos to avoid further reef deterioration. This could be achieved through video surveys of the fish community, night-time observations of the macroinvertebrate community, exclusion experiments that also keep out herbivorous macroinvertebrates, and/or experimental assessments of turf algae/CCA interactions.
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Косова, А. Л., Д. Б. Денисов y С. Б. Николаева. "Таксономическое разнообразие диатомовых комплексов голоценовых донных отложений малых водоемов депрессии озера Имандра". Biosfera 12, n.º 1 (9 de junio de 2020): 41. http://dx.doi.org/10.24855/biosfera.v12i1.538.
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A study of the taxonomic diversity of diatom algae in Holocene bottom sediments of two small water basins at the western coast of the lake Babinaskaya Imandra (Murmansk Region) has demonstrated the historical transformations of the species compositions of structures of diatom complexes associated with environmental changes in the Holocene. The water basins studied featured the predominance of the benthic and adhesive algae in the algal communities throughout the Holocene. The most drastic changes in the diatom complexes were associated with a tectonic event nearby the Imandra depression.
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Turner, Michael A., Leif J. Sigurdson, David L. Findlay, E. Todd Howell, Gordon G. C. Robinson y John F. Brewster. "Growth characteristics of bloom-forming filamentous green algae in the littoral zone of an experimentally acidified lake". Canadian Journal of Fisheries and Aquatic Sciences 52, n.º 10 (1 de octubre de 1995): 2251–63. http://dx.doi.org/10.1139/f95-816.
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Filamentous green algae, predominantly Mougeotia and Zygogonium, bloom frequently in the littoral zones of acidified lakes. Growth characteristics of Zygogonium-dominated filamentous green algae were studied for 4 yr in an experimentally acidified (pH 4.5) lake at the Experimental Lakes Area of northwestern Ontario. They were present in low abundance as periphyton (algal associations attached to surfaces) during spring, and as blooms of metaphyton (benthic algae unconstrained by surfaces) beginning in midsummer and reaching a maximum in early fall. Metaphytic filamentous green algae displayed high photosynthetic capacity in summer despite the oligotrophic nature of the acidified lake. The major factors controlling photosynthetic rates of Zygogonium were similar to those controlling Mougeotia, and included algal crowding, irradiance, dissolved inorganic carbon, and water temperature. Rates of photosynthesis were negatively dependent upon algal crowding, so that highest rates were associated with minimum algal crowding. Light requirements for photosynthesis were higher than those of the epilithon, which were dominant prior to acidification. The dependence of photosynthesis on ambient concentrations of dissolved inorganic carbon was partly regulated by water temperature. Anthropogenically caused releases from growth limitations (e.g., increased availability of limiting nutrients, increased water temperature, and extension of the growing season) may cause proliferation of filamentous green algae in the future.
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Skelton, Posa A. y G. Robin South. "Annotated catalogue of the benthic marine algae of the Palolo Deep National Marine Reserve of Samoa". Australian Systematic Botany 15, n.º 2 (2002): 135. http://dx.doi.org/10.1071/sb00036.
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A total of 124 species of benthic marine algae is reported from the Palolo Deep National Marine Reserve on the island of Upolu (Western) Samoa (13°49′S, 171°45′W). Included in the catalogue are 88 Rhodophyceae, 12 Phaeophyceae and 24 Chlorophyceae. This represents the first survey of benthic marine algae for any site in the Samoan Archipelago in the last 76 years. A total of 90 species newly recorded for the region brings the total reported species to 288 (includes Cyanophyceae not reported here). This is about 68% of the current flora from, for example, nearby Fiji. Of the 11 sites investigated, the eastern algal rim of the main Deep (0–10-m depth) is the most diverse, with 68 species. The subtidal (up to 25 m deep) is also diverse with 57 species recorded. The least diverse of all the sites is the Borrow Pit with only six species.
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Selivanova, Olga N. y Galina G. Zhigadlova. "Marine Benthic Algae of the Commander Islands (Pacific Coast of Russia) with Checklist Revised in 2012". ISRN Oceanography 2013 (31 de marzo de 2013): 1–12. http://dx.doi.org/10.5402/2013/470185.
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A revised checklist of marine benthic algae of the Commander Islands (Russian Pacific) is presented. It is based on the authors’ field collections. The list of algae of the area totals to 187 species (36 Chlorophyta, 38 Ochrophyta, class Phaeophyceae, and 113 Rhodophyta) of these 44 species (9 Chlorophyta, 8 Ochrophyta, class Phaeophyceae, and 27 Rhodophyta) are added to the previous checklists (Selivanova and Zhigadlova, 1997). We also confirm the presence of 5 species on the Islands that were absent in our earlier material but were recorded by other authors (Phycodrys amchitkensis, Mastocarpus papillatus, Lithothamnion sonderi, Odonthalia dentata, and Pleonosporium vancouverianum). The species list of the newly recorded algae contains information on their ecology, fertility, and distribution. The algal taxonomy and nomenclature are updated with new world data.
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Journal, Baghdad Science. "Benthic Algae in Lower Zab Tributary and Tigris river". Baghdad Science Journal 1, n.º 2 (6 de junio de 2004): 311–16. http://dx.doi.org/10.21123/bsj.1.2.311-316.
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Benthic algae of Tigris river and one of its northern tributary the lower Zab were study at monthly intervals during Nov. 2001-Oct. 2002. Four sites were selected, a total of 115 species of algae were identified during this study, diatoms was the dominating group (86 species) followed by Chlorophyta (18 species), Cyanophyta (7species), Euglenophyta (2 species) and one species for each of Pyrrophyta and Chryzophyta. Pennate diatoms formed the major density within the identified algae and distributed among all stations especially the species Achnanthes minutissima, Navicula gracilis and Nitzschia palea, the diatoms bloomed in spring and autumn seasons. Bio-diversity and density of benthic algae in Tigris river was affected negatively by the entering waters from Lower Zab tributary, this was indicated by the decreasing values after the confluence.
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Ou, Chouly y Kirk O. Winemiller. "Seasonal hydrology shifts production sources supporting fishes in rivers of the Lower Mekong Basin". Canadian Journal of Fisheries and Aquatic Sciences 73, n.º 9 (septiembre de 2016): 1342–62. http://dx.doi.org/10.1139/cjfas-2015-0214.
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Seasonal hydrology is assumed to be an important reason why the Lower Mekong Basin supports highly productive and biodiverse inland fisheries. We used C and N stable isotope ratios of tissue samples to estimate primary production sources supporting fish biomass in the Mekong and three large tributaries in Cambodia. We used a Bayesian mixing model to estimate relative contributions of four alternative production sources — seston, benthic algae, riparian grasses, and riparian macrophytes. There was little seasonal variation in isotopic signatures of riparian plants, but benthic algae and seston showed large seasonal shifts in carbon ratios. Seston and benthic algae were the most important production sources supporting fish biomass overall during the dry season, and riparian vegetation was the most important source during the wet season. Sources contributed differentially to biomass of trophic and habitat guilds, especially during the dry season. A dam on the upper Sesan River has changed hydrology, channel geomorphology, and other factors and, compared with the other three rivers, its fish biomass appears to derive from algae to a greater extent.
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Cantonati, Marco, Eugen Rott, Daniel Spitale, Nicola Angeli y Jiří Komárek. "Are benthic algae related to spring types?" Freshwater Science 31, n.º 2 (junio de 2012): 481–98. http://dx.doi.org/10.1899/11-048.1.
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Kerswell, Ailsa P. "GLOBAL BIODIVERSITY PATTERNS OF BENTHIC MARINE ALGAE". Ecology 87, n.º 10 (octubre de 2006): 2479–88. http://dx.doi.org/10.1890/0012-9658(2006)87[2479:gbpobm]2.0.co;2.
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