Algal Vegetation Research Articles

Vitality and growth rate of agar plate-cultivated Antarctic microautotrophs: Analysis of PSII functioning by chlorophyll fluorescence parameters

In our study, we focused on the growth of three different microautotrophs isolated from Antarctic lichens (Placopsis contortuplicata, Solorina spongiosa) and cryptoendolithic algal vegetation. The isolates were purified and inoculated on agar plates, Bold´s Basal Medium (BBM). The growth of the cultures and the markers of physiological (photosynthetic) activity were monitored by chlorophyll fluorescence in 1 week intervals for 3 months after inoculation. For the assessment of photosynthetic activity, the method of slow Kautsky kinetics supplemented with saturation pulses was applied. Four chlorophyll fluorescence parameters calculated: (1) maximum quantum yield of PSII (FV/FM), (2) effective quantum yield of photosynthetic processes in PSII (ΦPSII), (3) non-photochemical quenching of chlorophyll fluorescence, and (4) background chlorophyll fluorescence ratio (F0/F0´). Troughout the cultivation period, the maximum quantum yield of PSII (FV/FM) showed high values in all three autotrophs with only slight increase in the first part of the cultivation period, followed by slight decrease in the second part. The ΦPSII values showed a rapid decline within the first 4 weeks of cultivation followed by more or less constant values in the isolates from P. contortuplicata and cryptoendolithic alga. Contrastingly, time course of ΦPSII rather showed an increase followed by a decrease in S. spongiosa isolate. NPQ (related to the activation of protective mechanisms) increased in the second part of cultivation period, the rate of increase and maximum values were species-specific. The species-specific differences in chlorophyll fluorescence parameters are discussed as well as their potential for evaluation of photosynthetic performance of in vitro cultivated algal/cyanobacterial cultures on agar plates.

A preliminary scheme for an aquatic vegetation classification in China

<p indent="0mm">Based on the data of more than 50,000 aquatic plant communities we investigated in China in the past 40 years, referring to the principles, units, and main structure in “A revised scheme of the vegetation classification system of China”, the classification systems of “The Vegetation of China” and the “World Vegetation Classification System”, this paper tries to establish an aquatic vegetation classification system in China preliminarily.The aquatic vegetation classification system in China has upgraded the aquatic vegetation formation to the aquatic vegetation formation group, and six vegetation formation are divided under it: emergent vegetation formation, submerged vegetation formation, rooted floating leaf vegetation formation, free-drifting vegetation formation, planktonic algae vegetation formation and epiphytic algae vegetation formation. At the same time, ten new vegetation subformations were added, including five freshwater vegetation subformations and five marine vegetation subformations. Aquatic vegetation is divided into 205 alliance groups, and 659 alliances ; 659 associations with the same name as the alliences, among which 91 alliances and 312 associations of algal vegetation; 114 alliances and 347 associations of herbs vegetation.

Various marginal marine environments in the Central Paratethys: Late Badenian and Sarmatian (middle Miocene) marine and non-marine microfossils from Pécs-Danitzpuszta, southern Hungary

The middle Miocene foraminifera and ostracod record of the Central Paratethys usually reflects stable normal marine epositional environments for the Badenian and more patchy, less stable restricted marine environments for the Sarmatian. A 17 m thick outcrop at Pécs-Danitzpuszta, Mecsek Mts, SW Hungary exposed an upper Badenian to Pannonian succession where foraminifers and ostracods document significant environmental changes. The basal layers of the section contain micro- and macrofossils indicating normal marine, shallow, warm, well-oxygenated habitat with relatively high-energy conditions and algal vegetation on the bottom, and represent the upper Badenian (13.82 to 12.65 Ma). The marine deposits are followed by coarse sandstone, breccia and siltstone layers barren of microfossils but containing rhizoliths. The sediments were probably subaerially exposed for some time. The following marine inundation, marked by the appearance of clays and limestones as well as fossils, was dated to the late Sarmatian (ca. 12 to 11.6 Ma) on the basis of the restricted marine microfossil assemblages from the upper part of the succession (Porosononion granosum Zone, Aurila notata Zone). This community is characterized by exclusively eurytopic forms indicating an unstable and vegetated marginal marine environment with fluctuations in salinity, as well as oxygen and food availability. Within the 5 m thick upper Sarmatian marine interval, a unique fresh- to oligohaline fauna characterizes a few layers in less than 1 m thickness. This fauna consists of highly euryhaline foraminifera and freshwater to oligohaline ostracod assemblages, indicating a temporary salinity reduction to 5–10 ‰. No similar freshwater fauna has been reported from the Sarmatian of the Central Partethys so far. The eventual disappearance of the foraminifera from the paleontological record coupled with a complete turnover in the ostracod fauna indicates the transition from the marginal marine Sarmatian Sea to the brackish Lake Pannon, marking the Sarmatian/Pannonian boundary (11.6 Ma).

Nearshore Fish Species Richness and Species–Habitat Associations in the St. Clair–Detroit River System

Shallow water riparian zones of large rivers provide important habitat for fishes, but anthropogenic influences have reduced the availability and quality of these habitats. In the St. Clair–Detroit River System, a Laurentian Great Lakes connecting channel, losses of riparian habitat contributed to impairment of fish populations and their habitats. We conducted a seine survey annually from 2013 to 2019 at ten sites in the St. Clair and Detroit rivers to assess riparian fish communities, and to identify habitat attributes associated with fish species richness and catches of common species. We captured a total of 38,451 fish representing 60 species, with emerald shiner Notropis atherinoides composing the largest portion of the catch. We used an information-theoretic approach to assess the associations between species richness and catches of 33 species with habitat variables (substrate, shoreline vegetation types, and aquatic macrophyte richness). Sand, cobble, and algal substrates and shoreline vegetation were important predictors of species richness based on a multimodel inference approach. However, habitat associations of individual species varied. This work identified manageable habitat variables associated with species richness, while identifying potential tradeoffs for individual species. Further, this work provides baselines for development and evaluation of fish community and shoreline habitat restoration goals.

Degradation of a photophilic algal community and its associated fauna from eastern Sicily (Mediterranean Sea)

The status of the “Biocoenosis of the Infralittoral Algae” of the upper infralittoral zone (at 5 m depth) from two selected stations along the eastern coast of Sicily (Ionian Sea, Mediterranean) was studied with a multiproxy approach involving the study of algae and associated protist and animal organisms, including foraminifers, serpulids, molluscs, bryozoans and ostracods. Scraped samples (40x40 cm) were collected at selected seasons during a 2-year period (2015-2016) in order to identify possible seasonal and spatial differences between the two stations, and to compare present data with historical ones. A community made up of the algae Halopteris scoparia, Padina pavonica, Dictyota dichotoma, Ellisolandia elongata and several other geniculate coralline algae was found in sites historically colonised by a Cystoseira brachycarpa community, which was not found during our study. These algae presently structure the community and provide substratum for several associated epibiotic species. Hierarchical cluster analysis and Non-Metric Multi-Dimensional Scaling Ordination significantly differentiate the communities between the two stations but show no clear seasonal trend. Differences largely relate to changes in the algal vegetation and the impact produced by the regression of structuring species on epibiots (especially serpulids and bryozoans). Comparison with historical algal data from the area indicates the disappearance of Cystoseira brachycarpa, which was present at least until the last ’1990s, and a community degradation with a considerable loss in species richness. This parallels observations in other Mediterranean areas, and could be related to the increase in echinoid population density and their heavy grazing activity.

Combined Hydrothermal Conversion of Biomass (Algae and Aquatic Vegetation) from Lake Baikal Littoral Zone and Heavy-Oil Resids to Produce Biofuel

The prodigious growth of filamentous algae that has been occurring since 2011 in the littoral zone of Lake Baikal poses an acute ecological problem. Samples of algal biomass and aqueous vegetation were collected from the littoral zone of Lake Baikal and converted by hydrothermal treatment into biofuel in the presence of ammonium heptamolybdate. It was demonstrated that algal biomass from the Baikal littoral zone could be a potential source of feedstock for producing biofuel by thermocatalytic treatment. The addition of heavy-oil resids to algal and aquatic vegetation biomass increased the motor-fuel yield and modified its composition.

한국 서남해역 무안, 진도와 거문도의 춘계 해조식생

한국 서남해역 무안, 진도와 거문도의 춘계 해조식생

Use of remotely sensed data in mapping underwater landscapes of Srednyaya Bay (Peter the Great Gulf, Sea of Japan)

We examine the selection criteria for satellite images and methods of processing them in the process of mapping underwater landscapes using remotely sensed data, discuss the interpretation principles and algorithms as well as some issues related to the support of observations with field material. It is shown that a detailed landscape mapping of shallow marine waters by methods of visual and automated interpretation requires multispectral superhigh spatial resolution images. Results of investigations made on underwater profiles by using lightweight diving outfits were employed to describe seven types of underwater landscapes, and echo sounder measurements were used in constructing the digital elevation model for the bottom of Srednyaya Bay. It is established that the regions for which it was possible to carry out a reliable interpretation of data from the IKONOS-2 spacecraft are in the range of depths between 0 and 10 m and make up about three-fourths of the area of the bay bottom. Ten facies were identified and put on the map, for each of which we determined the area, the range of depths and the mean depth of propagation. Remotely sensed data were used to assess the contribution (in the spatial structure of the geosystem) of algal vegetation on the littoral; the eelgrass fields were ranked according to the degree of projective cover. As a result of a clustering according to the similarity of spectral attributes, we identified ten groups of pixels of the image analyzed. An analysis is made of the agreement between the distribution of facies identified by expert interpretation and results of an automated classification of pixels, and the contours of landscape units were updated. The conclusion is drawn regarding integration of the computer-aided and visual approaches to interpretation of remotely sensed data for shallow marine waters leading to a “hybrid” express method of mapping landscapes of shallow marine waters.

First Atlantic record of the green alga Parvocaulis exiguus from St. Eustatius, Dutch Caribbean

The Polyphysaceae is a well-studied family of green algae occurring in tropical and warm-temperate regions around the world. One of its species, Parvocaulis exiguus (Solms-Laubach) S. Berger et al. (Phycologia 42: 506-561, 2003), has previously been reported from both the Indian and the Pacific Oceans. This report presents the first record of Parvocaulis exiguus from the Atlantic Ocean. It was collected at 18 m depth from rocky substrata surrounded by seagrass off the Dutch Windward Caribbean island St. Eustatius. Owing to its small size and close resemblance to co-occurring species, it is possible that this species has been previously overlooked in the Atlantic. Although Polyphysaceae have been intensively studied in the Caribbean and other Atlantic regions, this is not the case for subtidal algal vegetation on St. Eustatius. Parvocaulis exiguus could have been present for a longer time around St. Eustatius or it could have been introduced with shipping. Future investigations may show if Parvocaulis exiguus will be observed in additional locations in the Caribbean.

동해안 울릉도 해역의 해조군집

A subtidal marine benthic algal vegetation at Ulleungdo Island, the eastern coast of Korea was investigated to clarify the community structure and vertical distribution by quadrat method at seven stations in May and August 2014. The total number of marine algal species was 148 species composed of the green algae of 12 species, the brown algae of 40 species and the red algae of 96 species. Mean biomass in dry weight was 94.8 g dry weight m -2 in study sites, 98.1 g dry weight m -2 in upper tidal level, and 86.6 g dry weight m-2 in middle level. The R/P and (R+C)/P value reflecting flora characteristic were 1.9 and 2.3, respectively. Three groups produced by cluster analysis, one including sites Neunggeol, Daepung, Jukdo, second including sites Gongam, Ssangjeongcho and the other including sites Gwaneum, Hangnam, showed meaningful difference in similarity (about 40%), each other. The number of marine algal species and biomass in Ulleungdo Island area were markedly reduced comparing that in the previous studies. This result may suggest probably change of algal vegetation in future, considering the physical and chemical pollutions loaded in the coastal marine environment of this area.

Benthic algal vegetation in Isfjorden, Svalbard

Benthic algal vegetation was investigated at 10 sites in Isfjorden, Svalbard. Five sites were visited during summer 2010 and five during summer 2012. Both the littoral and sublittoral vegetation were sampled, the littoral by hand-picking and use of a throwable rake and the sublittoral using a triangular dredge. A total of 88 different taxa were registered, comprising 17 Chlorophyta, 40 Ochrophyta, 30 Rhodophyta and the Xantophyceae Vaucheria sp. The green algae Ulvaria splendens (Ruprecht) Vinogradova was recorded in Svalbard for the first time. Most of the sites consisted of hard bottom substrate, but one site, Kapp Wijk, consisted of loose-lying calcareous red algae (rhodoliths) and had species not recorded elsewhere. The sublittoral at the other sites was dominated by kelp. Molecular analysis confirmed the presence of the red alga Ceramium virgatum and a dwarf form of the brown alga Fucus vesiculosus . This study provides a baseline for future studies investigating changes in the vegetation due to environmental changes. Keywords: Arctic; Svalbard; Isfjorden; benthic algal diversity. (Published: 11 August 2015) To access the supplementary material for this article, please see supplementary files in the column to the right (under Article Tools). Citation: Polar Research 2015, 34 , 25994, http://dx.doi.org/10.3402/polar.v34.25994

부산시 오륙도 주변 해역의 해조 군집

Marine algal flora and community structure were seasonally investigated at Oryukdo, on the southeast coast of Korea, from March 2011 to February 2014. A Total of 66 seaweed species including 6 green, 7 brown and 53 red algae were identified and 23 species were found throughout the survey period. Seaweed biomass was maximal during summer in 2012 (2276.2 g wet weight <TEX>$m^{-2}$</TEX>) and minimal in winter in 2012 (9.1 g wet weight <TEX>$m^{-2}$</TEX>). The dominant species in term of biomass were Undaria pinnatifida, Dictyopteris prolifera, Dictyota dichotoma, Sargassum horneri, Rhodymenia intricata, Acrosorium polyneurum, and Polyneura japonica during the suvery period. The flora could be classified into six functional groups: coarsely branched form (30.3%), filamentous form (24.2%), thick leather form (19.7%), sheet form (15.2%), jointed calcareous form (7.6%), and crustose form (3.0%). The numbers of marine algal species in the Oryukdo area were markedly reduced when compared with previous studies at Dongbaekseom in 1971. These results suggest possible future changes in the algal vegetation, considering the physical and chemical pollution loadings in the coastal marine environment of this area.

Marine macroalgae and associated flowering plants from the Keret Archipelago, White Sea, Russia

The marine algal flora of the Keret Archipelago ( N, E) in the White Sea, Russia was investigated during 2008. Over 250 algal records from more than 15 islands and several sites on the adjoining mainland produced a total of 62 algal species. This raised the total from 56 to 88 species of Chlorophyta (23 species), Phaeophyceae (31 species), Rhodophyta (33 species), and Tribophyceae (1 species) of which seven were new records or verifications of ambiguous records for the White Sea and 11 species are new for the Keret Archipelago. The new or confirmed records included species of Blidingia, Eugomontia, Prasiola, Rosenvingiella, and Ulothrix (Chlorophyta), Acrochaetium, Colaconema (Rhodophyta), and Vaucheria (Tribophyceae). Five species of flowering plants (Aster, Plantago, Triglochin, and Zostera) were associated with the macrophytic algal vegetation of the region. Five fucoid algae in Pelvetia, Fucus, and Ascophyllum provide a picture of a temperate flora. Regardless, the overall species richness is consistent with an arctic nature to the flora. This discrepancy is attributed to the `filter` provided by the Barents Sea of the Arctic Ocean for post-glacial colonization of the White Sea.

부산시 기장 주변 해역의 해조 군집 변동

Marine algal flora and community structure were investigated seasonally at three sites in Gijang on the south-east coast of Korea from February 2006 to January 2007. A Total of 74 species were collected and identified, including 8 green algae, 16 brown algae, and 50 red algae. Of these, 15 species were found throughout the survey period. Mean biomass was 823.2-1,615.4 g wet weight <TEX>$m^{-2}$</TEX> in winter, 689.1-3,196.8 g wet weight <TEX>$m^{-2}$</TEX> in spring, 574.5-1,219.9 g wet weight <TEX>$m^{-2}$</TEX> in summer, and 747.6-1,616.2 g wet weight <TEX>$m^{-2}$</TEX> in autumn. The flora could be classified into six functional groups: coarsely branched form (37.8%), thick leather form (18.9%), sheet form (13.5%), filamentous form (12.2%), jointed calcareous form (10.8%) and crustose form (6.8%). The R/P, C/P and (R+C)/P values reflecting the flora characteristics were 3.13, 0.50 and 3.63, respectively. The number of marine algae species and the biomass in Gijang area were markedly reduced when compared with previous studies. This result suggests possible future changes in the algal vegetation, considering the physical and chemical pollution loadings in the coastal marine environment of this area.

Trophic structure in natural habitats of the abalone Haliotis discus hannai with distinct algal vegetation of kelp and crustose coralline algae: implication of ontogenetic niche shifts

The abundance, species composition, and stable isotope ratios of benthic organisms were investigated to determine the trophic structures in abalone (Haliotis discus hannai) habitats, which are characterized by contrasting vegetation of crustose coralline algae (CCA) and kelp beds. A size–frequency analysis revealed that juvenile abalones with shell lengths (SLs) smaller than ~30 mm primarily inhabited CCA beds, whereas adults were abundant in kelp beds. Stable isotope analyses indicated that CCA beds were composed of a single food chain, whereas kelp beds supported multiple food chains. The abalone were divided into three size groups to estimate potential species interactions during their ontogeny. A small gastropod, Homalopoma sangarense, was the most abundant species, but is suspected to be less competitive with abalone, especially in CCA beds. An abundant starfish Asterina pectinifera appeared to function as a potential predator of juvenile abalones in both CCA and kelp beds. We concluded that CCA beds are essential for immediate post-settlement processes of abalones, whereas kelp beds are more important for providing refuge and food sources for adult abalones. The present study highlights that ontogenetic niche shifting can be a successful life-history strategy to sustain the abalone population in a subtidal rocky shore ecosystem.

Seasonal periodicity and reproduction of brown algae (Phaeophyceae) at Puerto Deseado (Patagonia)

Abstract Puerto Deseado is a locality on the Atlantic coast of Patagonia (47°45′ S, 65°54′ W) with a ria (fjord-like estuary) several kilometres long that follows the course of Rio Deseado. From 1969 to 1972, we followed the development of 50 species of mostly intertidal brown macroalgae at five sites, one outside the ria and four within. Collections and observations were made at least once monthly to determine species identities, vegetative and reproductive states of the thalli, and variations between the different sites. Several environmental factors were used to describe the sites, including seawater temperature, season, and hydrodynamics. In summer, there were more species, coincident with the highest proportion of plurilocular sporangia. In contrast, unilocular sporangia appeared mostly in autumn. The difference between the five sites was well defined: nine species from the outermost site did not occur inside the ria, and only 13 species were found at all five sites. The number of species gradually declined towards the interior of the ria. The aim of this study was to document brown algal vegetation at the beginning of the 1970s to provide a baseline dataset before the start up of large-scale port activity.

The algal vegetation in the outer part of Isfjorden, Spitsbergen: revisiting Per Svendsen's sites 50 years later

The benthic algal vegetation was investigated at two different sites in the outer part of Isfjorden, Svalbard, during 27-29 July 2007. One exposed site at Kapp Linne´ and one sheltered site in Ymerbukta were sampled both in the littoral and sublittoral zones. A total of 83 different taxa were recorded, 81 from the sublittoral and 40 from the littoral zone. The sublittoral zones at the two sites did not differ much in terms of the taxa recorded, but the number of species in the littoral differed between the two sites: Kapp Linne´ had 39 while only five species were found in Ymerbukta. The results are compared to a survey made by Per Svendsen in 1954 and 1955 in order to seek any changes in the diversity. Even though the number of species is difficult to compare directly, we registered a higher species number than Svendsen did 50 years ago. The difference seemed more pronounced in the littoral zone than in the sublittoral. Possible explanations for the differences between the two investigations are discussed. Two species not previously recorded in Svalbard, Antithamnionella floccosa and Litosiphon laminariae, were registered. Keywords: Arctic; Svalbard; long-term changes; algal diversity (Published: 26 March 2012) Citation: Polar Research 2012, 31 , 17538, DOI: 10.3402/polar.v31i0.17538

A geochemical investigation of hydrologically derived threats to rare biota: the Drummond Nature Reserve, Western Australia

The Drummond Nature Reserve (DNR), a high-value conservation area 100 km northeast of Perth, Western Australia, contains two rare freshwater claypans and a diverse range of rare and threatened vascular plants. Groundwater/surface-water interactions were investigated via isotopic (δ18O and δD) and major ion analysis. The groundwater chemical and isotope analyses combined with nutrient data allowed for the assessment of potential hydrologically derived threats to the claypans and their associated conservation values. Groundwater composition is typically Na–Cl to Na–Mg–Cl; whereas the claypan’s ephemeral fresh surface water is Na–Cl–HCO3. Distinct δ18O and δD isotopic signatures for the claypan surface waters and adjoining groundwaters indicate that there currently is minimal connection between these two hydrological systems. Hence the current threat to the freshwater claypans and associated biota from rising saline and acidic groundwater is minimal. Elevated nutrient (N) levels identified in groundwaters along the reserve’s western boundary may be linked to fertiliser regimes employed in adjoining agricultural lands. The ecosystem associated with the southwest claypan is particularly vulnerable to N and P inputs via surface-water flows, which could cause algal blooms, vegetation degradation and weed infestation.

A Study on the Community Structure of Subtidal Marine Algae in Kijang, Korea

A subtidal marine benthic algal vegetation at Kijang, the southern east of Korea was investigated to clarify the community structure and the pattern of geographical distribution by a quadrat method along a transect line between February 2006 and January 2007. Total 59 species including 6 of green algae, 14 of brown algae, 39 of red algae were collected and identified. Among these species, 14 species were found throughout the year. Annual mean biomass in wet weight of total vegetation, maximum biomass was recorded in winter and spring seasons, and decreased in summer season. Dominant species was Prionits cornea in terms of biomass, and subdominant species were Phycodrys fimbriata and Gelidium amansii. Coarsely branched form was the most abundant accounting 64.4% of the total value. Seasonal variations in algal bio- mass were principally linked to fluctuations in biomass of coarsely branched and thick leathery form algae. The R/P, C/P and (R+C)/P value reflection flora characteristics were 2.79, 0.43 and 3.21, respectively. Two groups produced by cluster analysis, one including sites Duho, Dongbaek and the other including sites Seoam, Mundong, showed meaningful difference in similarity, each other. In conclusion, the number of marine algae species in Kijang was reduced comparing with the previous studies.

동해 연안 영일만 조간대 해조류의 군집구조

An intertidal marine benthic algal vegetation and vertical distribution at Youngil Bay, the eastern coast of Korea was investigated to clarify the community structure and vertical distribution by quadrat method from February 2003 to January 2009. Marine algae identified from the area were 152 species; 25 green, 38 brown and 89 red algae. The dominant species were Ulva spp., Ulva pertusa, Chaetomorpha moniligera, Undaria pinnatifida, Sargassum horneri, S. miyabei, S. thunbergii, Gelidium amansii, Corallina pilulifera, Grateloupia elliptica, G. filicina, Prionitis cornea, Chondrus ocellatus, Chondracanthus intermedia, Acrosorium polyneurum, Chondria crassicaulis, Polysiphonia morrowii and Symphyocladia latiuscula at study sites. The vertical distribution of intertidal marine algae was divided into three distinct zones. They were characterized by Porphyra spp. and Ulva spp. at the upper, Ulva spp. and Ulva pertusa at the middle, and Sargassum spp., Gelidium amansii, Grateloupia spp., Chondrus ocellatus and Chondria crassicaulis at the lower zones, respectively. Functional form group analysis showed that coarsely branched forms comprised 44.7% of the algal community, whereas thick leathery forms, sheet forms and filamentous forms comprised 6.6-25.7%. R/P, C/P and (R+C)/P values were 2.34, 0.66 and 3.00, respectively.