The sub-Antarctic Magellan Ecoregion is a unique biogeographic area located at the southern tip of South America, which has exceptional marine flora and high endemism. Along the coastline, the ...ochrophytes
Macrocystis pyrifera
and
Lessonia flavicans
form vital underwater forests that serve as critical habitats, providing shelter, food and breeding grounds for a diverse marine organisms. These algal species are also important components used in the food industry and biomedicine, due to their high lipid, amino acid and fiber content. In this study, we investigated the intra-thallus variation of fatty acids among the different morphological structures (fronds, stipes and holdfast) of
M. pyrifera
and
L. flavicans
collected in Rinconada Bulnes during spring, 2021. The stipes of
M. pyrifera
(3.73 ± 1.73%) and the fronds of
L. flavicans
(3.35 ± 0.97%) both exhibited high lipid content. Saturated fatty acids were highest in the holdfast of
M. pyrifera
(37.82 ± 0.06%) followed by the fronds of
L. flavicans
(34.30 ± 0.10%). Notably, monounsaturated fatty acids showed higher levels en the holdfast of
L. flavicans
(46.45 ± 0.19%) followed by the stipes of
M. pyrifera
(43.04 ± 0.08%). The fronds of both
M. pyrifera
(32.38 ± 0.26%) and
L. flavicans
(28.89 ± 0.23%) showed high levels of polyunsaturated fatty acids. These findings provide valuable insight into the intra-thallus variation of fatty acids in different morphological structures of
M. pyrifera
and
L. flavicans
, highlighting their potential nutritional and biomedical importance as the most representative kelps in the Magellan region.
COMPOSITION OF ASCOLICHEN IN GAYO HIGHLAND Wardiah, W; Ratnasari, Desi; Iswadi, I ...
Biotik (Universitas Islam Negeri Ar-Raniry. Prodi Pendidikan Biologi),
04/2021, Letnik:
9, Številka:
1
Journal Article
Recenzirano
Odprti dostop
Ascolichen is group of lichen composed by ascomycetes (the mycobiont) and algae (the photobiont) species which play ecological and industrial roles. The campus area of Syiah Kuala University Gayo ...Lues is a part of the Gayo Highland which has specific environmental characteristics. The research aim was to determine the ascolichen species, the type of talus and the substrate characteristics. This study used a qualitative approach with research type was an exploratory survey. Data collection was carried out at 2 stations, namely Station I (campus area) and Station 2 (outside campus area). Data was analyzed descriptively. The results showed that there were 28 species of ascolichen found in the location which belong 3 classis, 6 orders, 15 families, and 25 genera. Moreover, the thallus types of lichen species were crustose (16 species), foliose (8 species), and fruticose (4 species). The types of lichen substrate were tree trunks (22 species), dead woods (9 species) and rocks (4 species). The acidity of the substrates ranges 4-6 (acidic).
Shifts from coral-dominated to macroalgal-dominated states on coral reefs are typically attributed to overfishing, often in combination with natural or other anthropogenic disturbances. However, a ...recent study attributed increased macroalgal cover to enhanced nutrient supplies alone without associated reductions in herbivorous fishes. This highlights the need to understand macroalgal responses to terrestrial runoff and how this can contribute to their proliferation on coral reefs. We explored the responses of two common brown macroalgae, Sargassum mangarevense (Grunow) Setchell and Padina boryana Thivy to nutrient addition, sediment addition, and mechanical damage in 3 field experiments. In the first experiment, we exposed all experimental units to herbivores and found that nutrient addition ameliorated biomass loss of both S. mangarevense and P. boryana by 79% and 47%, respectively, while sediment addition had no effect on either species. Exploring the underlying causes of these findings, we determined nutrient addition caused a 5% increase in toughness of S. mangarevense and a 51% increase in calcification of P. boryana. In a final experiment, both mechanical damage and nutrient addition independently increased calcification of P. boryana, while an antagonistic interaction between these factors for S. mangarevense suggests an upper limit to thallus toughness. Overall, we demonstrate that nutrients from anthropogenic terrestrial runoff may support macroalgal proliferation on coral reefs by ameliorating short-term biomass losses in the presence of herbivores. Further, we suggest the mechanism behind this amelioration may be changes in algal physical characteristics, specifically thallus toughness and calcification, in response to anthropogenic or natural disturbances.
•Nutrients ameliorated short-term biomass loss of macroalgae.•Padina boryana calcification increased with nutrients and mechanical damage.•Sargassum mangarevense toughness increased with nutrients and mechanical damage.•Higher macroalgal calcification and toughness may reduce short-term biomass loss.
Alginic acid is an intermediate product in the alginate extraction process. In this study, alginic acid was generated from three separate sections of the thallus. The study aimed to define the ...influence of alkali solvents for pretreatment and the thallus parts from S. polycystum to produce alginate. Thus, this study identifies the proper utilization of seaweed as a source of alginate. The extraction procedure to obtain alginic acid was performed using Na2CO3 at a 2% concentration. The pretreatment improved the quality before extraction by soaking in KOH as a solvent. The statistical analysis was used to define significant differences in the pretreatment and thallus parts of the S. polycystum using ANOVA and the Tukey test as the post hoc. Alkali pretreatment and thallus sections substantially influence alginic acid yield, viscosity, and gel strength. Yield, ash content, moisture, pH, viscosity, whiteness degree, and gel strength of the best alginic acid chosen (pretreatment with KOH 0.90% from the basal section) were around 21.51 %, 10.34 %, 7.04 %, 2.54, 53.37 cP, 57.91 %, and 58.80 g/cm2, respectively. Except for the ash content parameter, the qualities of the alginic acid generated satisfied the standard. In conclusion, it is a better understanding of the alginate production from different thallus parts, making utilization more effective.
Wiesnerella denudata (Mitt.) Steph., a complex thalloid liverwort in the family Wiesnerellaceae (Marchantiales), is reported as a new species to Peninsular India from the Anamudi Shola National park ...in the Western Ghats of Kerala. This species is easily confused with another thalloid liverwort, Dumortiera hirsuta (Sw.) Nees, due to similar morphological characters, especially size of thallus, colour and habit. Wiesnerella denudata is characterised by the presence of elevated air pores which can be seen with the help of a hand lens or even with naked eye, subsessile rotund male receptacle, raised female receptacle with deeply dissected carpocephalum and absence of pseudoperianth. A detailed account of the species along with photographs and SEM images of spores is provided here.
Hair lichens (Alectoria, Bryoria, Usnea) with high surface-area-to-mass ratios rapidly trap moisture. By photography and scanning we examined how internal water storage depended on morphological ...traits in five species. Specific thallus mass (STM, mg DM cm−2) and water holding capacity (WHC, mg H2O cm−2) after shaking and blotting a fully hydrated thallus increased with thallus area. STM was ≈50% higher in Alectoria and Usnea thalli than in Bryoria. WHC was highest in Alectoria while percent water content of freshly blotted thalli was lowest in Usnea. Thallus area overlap ratio (TAO), assessing branch density of the thallus, was highest in the two thinnest Bryoria; lower in the thicker Usnea. Within species, hair lichens increased their water storage by increasing branch density rather than branch diameter. The taxonomically related genera Alectoria and Bryoria shared water storage characteristics, and differed from Usnea. Hair lichens in lower canopies have among the lowest water storage capacity reported in lichens.
•We developed methods to study morphological traits and water storage in hair lichens.•Alectoria had higher water holding capacity than Bryoria and Usnea.•Usnea contains lower percent water when saturated than Alectoria and Bryoria.•Within species, hair lichens increase water storage by increasing branch density.•Hair lichens in lower canopy have among the lowest water storage reported in lichens.
Intra‐thallus variation in fatty acid and pigment contents and profiles was investigated in five species of Laminariales (Alaria esculenta, Laminaria digitata, Laminaria hyperborea, Saccharina ...latissima, and Saccorhiza polyschides), and three Fucales (Ascophyllum nodosum, Fucus serratus, and Himanthalia elongata). Significant variation occurred across all species and compounds examined. Total fatty acids were generally higher in the fronds, with highest levels and largest variability observed in A. nodosum (1.5% of dry weight (DW) in the base, 6.3% of DW in frond tips). Percentages of the omega‐3 fatty acids 18:4 n‐3 and 20:5 n‐3 were generally higher in more distal parts, while 20:4 n‐6 exhibited a contrasting pattern, with higher levels in basal structures and holdfasts. Trends for pigments were similar to those for fatty acids in Laminariales. In the Fucales, highest levels were detected in the mid‐fronds, with lower concentrations in meristematic areas. Highest levels and greatest variability in pigments (e.g., chl a) was observed in F. serratus (1.07 mg · g−1 DW in the base, 3.04 mg · g−1 DW in the mid frond). Intra‐thallus variability was attributed to physiological functions of the respective thallus sections, e.g., photosynthetic activity, meristematic tissue, and to variations in physical attributes of the structures investigated. Regarding potential commercial nutritional applications, fronds appeared to represent most suitable source materials, due to higher levels of pigments, polyunsaturated fatty acids, and more preferable omega‐3/omega‐6 ratios.
ABSTRACT
Lichens occur in most terrestrial ecosystems; they are often present as minor contributors, but in some forests, drylands and tundras they can make up most of the ground layer biomass. As ...such, lichens dominate approximately 8% of the Earth's land surface. Despite their potential importance in driving ecosystem biogeochemistry, the influence of lichens on community processes and ecosystem functioning have attracted relatively little attention. Here, we review the role of lichens in terrestrial ecosystems and draw attention to the important, but often overlooked role of lichens as determinants of ecological processes. We start by assessing characteristics that vary among lichens and that may be important in determining their ecological role; these include their growth form, the types of photobionts that they contain, their key functional traits, their water‐holding capacity, their colour, and the levels of secondary compounds in their thalli. We then assess how these differences among lichens influence their impacts on ecosystem and community processes. As such, we consider the consequences of these differences for determining the impacts of lichens on ecosystem nutrient inputs and fluxes, on the loss of mass and nutrients during lichen thallus decomposition, and on the role of lichenivorous invertebrates in moderating decomposition. We then consider how differences among lichens impact on their interactions with consumer organisms that utilize lichen thalli, and that range in size from microfauna (for which the primary role of lichens is habitat provision) to large mammals (for which lichens are primarily a food source). We then address how differences among lichens impact on plants, through for example increasing nutrient inputs and availability during primary succession, and serving as a filter for plant seedling establishment. Finally we identify areas in need of further work for better understanding the role of lichens in terrestrial ecosystems. These include understanding how the high intraspecific trait variation that characterizes many lichens impacts on community assembly processes and ecosystem functioning, how multiple species mixtures of lichens affect the key community‐ and ecosystem‐level processes that they drive, the extent to which lichens in early succession influence vascular plant succession and ecosystem development in the longer term, and how global change drivers may impact on ecosystem functioning through altering the functional composition of lichen communities.
Bryophytes represent a sister to the rest of land plants. Despite their evolutionary importance and relatively simple body plan, a comprehensive understanding of the cell types and transcriptional ...states that underpin the temporal development of bryophytes has not been achieved. Using time-resolved single-cell RNA sequencing, we define the cellular taxonomy of Marchantia polymorpha across asexual reproduction phases. We identify two maturation and aging trajectories of the main plant body of M. polymorpha at single-cell resolution: the gradual maturation of tissues and organs along the tip-to-base axis of the midvein and the progressive decline of meristem activities in the tip along the chronological axis. Specifically, we observe that the latter aging axis is temporally correlated with the formation of clonal propagules, suggesting an ancient strategy to optimize allocation of resources to producing offspring. Our work thus provides insights into the cellular heterogeneity that underpins the temporal development and aging of bryophytes.
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•We generate a reference cell census for bryophytes•The collection of cell-type-specific genes accelerates gene discovery•We define the maturation and aging trajectory of M. polymorpha at single-cell resolution•The vigor of parent plants is determined by the number of offspring
Wang et al. profile transcriptomes of dormant gemmae and developing thalli of different stages at single-cell resolution, defining two maturation and aging axes of the main plant body of M. polymorpha. The inference of continuous developmental trajectories for each cell type provides insight into the maturation program of M. polymorpha.
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