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Eelgrass, Zostera marina L., is vital to marine ecosystems, providing habitat, filtering pollutants, improving water quality, and serving as a source of bioactive compounds for pharmaceuticals. This study aimed to isolate and identify phenolic compounds from Z. marina, biotransform the main metabolite, rosmarinic acid (RA), and evaluate the anti-tyrosinase activity of these compounds. Various chromatographic techniques were employed to isolate compounds from Z. marina (1-4). Compound 1, exhibiting broad pharmaceutical activity, was biotransformed by Deinococcus geothermalis amylosucrase (DgAS) into two new glycosylated products (5-6). The isolated and biotransformed compounds were tested for anti-tyrosinase activity using a mushroom tyrosinase assay. Molecular docking and quantum chemical calculations were conducted to clarify the binding mode and reactivity of the compounds. The isolated compounds were identified via NMR and HR-MS as rosmarinic acid (RA) 1, methyl rosmarinate 2, methyl isorinate 3, and pinoresinol 4′-O-β-D-glucopyranoside 4. This is the first report of isolating and identifying compounds (2-4) from the Zosteraceae family. The glycosylated compounds were identified as rosmarinic acid 4-O-α-D-glucopyranoside 5 and rosmarinic acid 3′-O-α-D-glucopyranoside 6. Among all compounds, (4-6) showed significant tyrosinase inhibition, with rates of 55.5%, 22.3%, and 30.8%, respectively, compared to arbutin. The two glycosylated products exhibited better anti-tyrosinase activity than 1. In silico results aligned with in vitro findings. This study highlights Z. marina's potential as a source of polyphenolic compounds with significant anti-aging activity, emphasizing the discovery of new anti-aging ingredients to enhance quality of life. [ABSTRACT FROM AUTHOR]

UK recreational boating infrastructure in UK ports and harbors consistently coincides with Marine Protected Area designation. Under UK Marine Protected Area designations, vulnerable seabed habitats such as seagrass beds require protection and/or restoration. Mooring and anchoring activity has coincided with increasing concerns over the conservation status of the climate-buffering properties of seagrass beds in the literature and from empirical studies. Up until this study, there has yet to be a significant UK based trial of a number of modified moorings to see their impact on the reduction in pressure on vulnerable benthic habitats. In May 2019, we installed and tested five Advanced Mooring Systems (AMS) in Cawsand Bay, Plymouth Sound, UK. A further 10 such devices were installed in 2021 after the COVID 19 pandemic. The original five devices tested were 'Stirling' systems, whereby the rode is raised above the seabed by use of several submerged floats set at 1.5–2 m intervals along the chain, leading to a top mark that secures the vessel. Each AMS were attached to the seabed using helical screwpiles by commercial divers using a waterproof hydraulic wrench. The devices have held securely since May 2019, and monitoring of seagrass around these five moorings has occurred regularly (at approximately 6 monthly intervals) between May 2019 and May 2023. No seeding or transplantation to prime seagrass recovery has taken place around the base of the moorings during this period. Nevertheless, during the sixth dive survey in May 2023, 4 years after installation, a 212% increase in seagrass density was recorded within the zone previously abraded by the moorings and riser chains. Blade length of the longest seagrass shoots has also increased over the test period. Semi-structured interviews were held with participants in the trial from boat users, NGOs and government agencies to ascertain attitudes and responses to seagrass conservation and the use of AMS. Interaction with stakeholders are important to securing positive community buy-in to such interventions. We recommend that for small sailing craft and powerboats these systems provide a fit-for-purpose engineering and ecological solution to support the restoration of seagrass beds, but that such initiatives must be accompanied by significant understanding and interaction with local stakeholders. [ABSTRACT FROM AUTHOR]

In order to study the effects of oxalic acids on plant growth and Pb accumulation in different parts of the plants of intercropping Arabis alpina and Zea mays, pot experiment was conducted to investigate the changes of oxalic acid contents of the plants and Pb accumulation through exogenous oxalic acid addition (0, 5, 25 and 50 mmol kg−1). The results showed the root biomass of intercropped A. alpina and total biomass of Z. mays increased by 3.22 folds and 2.97 folds with 5 mmol kg−1 oxalic acid treatment. The oxalic acid contents of shoots and root secretions decreased by 86.5% and 44.3%, respectively. The BCF (bio-accumulation factor) and TF (translocation factor) of intercropping A. alpina reduced under 25 − 50 mmol kg−1 oxalic acid treatments. There were relationships between exogenous oxalic acid treatment concentrations and oxalic acid contents of A. alpina shoots, Z. mays root secretions. The Pb contents of shoots of A. alpina and Z. mays were related to exogenous oxalic acid additions and oxalic acid contents of shoots. In general, 5 mmol kg−1 oxalic acid treatment, that can improve plant growth of intercropped A. alpina and Z. mays, which Pb translocation and accumulation of A. alpina were promoted, whereas Pb accumulation of A. alpina was inhibited with 25 − 50 mmol kg−1 concentrations addition. This study will provide a basis for promoting the application of phytoremediation techniques and efficient crop production in heavy metal contaminated areas. Hyperaccumulators intercropped with crops will remediate heavy metal soils or mitigate the damage caused by heavy metals to plants through oxalic acid secretion by the root system. However, the effect of oxalic acid changes on plant growth and Pb accumulation is lacking. Our study investigated the changes in oxalic acid content at different concentrations and sites affected the ability of intercropped plants to grow and accumulate Pb. This work shown that under intercropping conditions, exogenous oxalic acid promotes intercropped plant growth as well as soil pH reduction, Pb content in shoots both Arabis alpina and Zea mays is influenced by exogenous oxalic acid content, while lower Z. mays roots Pb content is determined by a combination of exogenous addition and aboveground oxalic acid content. Low concentrations of oxalic acid promoted Pb enrichment in roots of A. alpina, while reducing the uptake of Pb content in Z. mays. This article gives us a better understanding for the response of intercropping plants to the use of organic acids under heavy metal stress and how to modify their environment so as to favor growth. [ABSTRACT FROM AUTHOR]

"Beauty Regimes: A History of Power and Modern Empire in the Philippines, 1898-1941" by Genevieve Alva Clutario explores the connection between beauty and feminine gender ideals in the Philippines. The book examines the role of beauty contests in Filipino culture and analyzes the project of beauty production as a form of self-empowerment and a tool of nationalism during the American colonial period. It also delves into the history of embroidery in the Philippines, highlighting the labor of non-elite women in the transnational industry. The book concludes with a study of high fashion in the Philippines and the significance of the terno as a marker of elite women's modern nationalist identity. Using a variety of sources, including newspapers, magazines, memoirs, and colonial archives, the book offers fresh insights into the American colonial period in the Philippines through the lens of fashion and beauty. [Extracted from the article]

The connection between Konstantin Stanislavsky and Jerzy Grotowski is often overlooked or underplayed because there are substantial distinctions between them in terms of practices and approaches. In Part I of this essay, I examine Grotowski's reflections on Stanislavsky's final experiments, which the Polish director considered to constitute the culmination of the System, as well as the starting point for his own work at the Laboratory Theatre. In Part II, I explore the implications of the Stanislavsky-Grotowski lineage and its legacy for contemporary performance research by relating Stanislavsky's idiosyncratic usage of the term perezhivanie, translated by Martin Kurten as "conscious experience," to the neuroscientific investigation of embodied experience, discussed by Rhonda Blair, and to Grotowski's own conception of consciousness as a form of embodied awareness. I then focus on a crucial point of convergence between the Russian and Polish directors' respective approaches lying beyond the purview of neuroscience, namely, the correlation between the physical and the spiritual, prompting Sharon Carnicke to invent the neologism "physiospiritual." I infer that the legacy of the Stanislavsky-Grotowski lineage consists in an expanded notion of perezhivanie that I relate to philosopher Alva Noë's phenomenological understanding of the interrelation of consciousness and experience. [ABSTRACT FROM AUTHOR]

The dead seagrass leaves accumulated on the seashores, also known as beach (seagrass) wracks, can be considered a sustainable and ecologically beneficial source for application in the construction sector. An innovative thermal insulation material composed of Zostera marina seagrass leaves was developed using bicomponent fibers as a binding agent. The bicomponent fibers consisted of polypropylene in the core and polyethylene in the sheath. This work aimed to investigate the effect of mat density on mechanical properties (compression and internal bond strength), thermal conductivity and fire properties. The seagrass-based (SG) mats were compared to reference mats consisting of wood fibers (WF). The digital and scanning electron microscopy investigation revealed the differences in the bonding mechanism between the two types of mats. Although slightly higher than WF mats, the thermal conductivity of SG mats still varied from 0.039 to 0.051 W m−1 K−1 and is comparable to those of other natural fiber-based boards with the same density range. The low peak heat release of SG mats (up to 63% lower than wood fiber-based mats) indicates their high resistance to fire. SG mats provide novel possibilities for using new environmentally friendly materials intended for ceiling and partition applications. [ABSTRACT FROM AUTHOR]

The genus Zelkova (Ulmaceae) has occurred in Europe and Southwest Asia since the Eocene represented mostly by the fossil-species Z. zelkovifolia. Currently, relict populations of Z. abelicea, Z. sicula and Z. carpinifolia can be found in Crete, Sicily and the Euxino-Hyrcanian province, respectively. To reveal relationships between extinct and extant Zelkova species, we compared fossil Miocene leaves of Z. zelkovifolia and leaves of extant species using morphological leaf characteristics and statistical methods (Tukey's test, discrimination analysis, principal component analysis, agglomeration). The fossil leaves of Z. zelkovifolia appeared more variable and generally intermediate between all three extant species. The lowest level of significant differences was found between Z. zelkovifolia and Z. abelicea in the leaves from fertile shoots and between Z. zelkovifolia and Z. sicula leaves from vegetative long shoots. The intermediate positions of fossil leaves of Z. zelkovifolia between leaves of Z. abelicea, Z. sicula and Z. carpinifolia could indicate that the extinct species was an ancestor of all three extant taxa. Consequently, this result suggests divergence between Z. abelicea, Z. sicula and Z. carpinifolia no earlier than the late Miocene and/or during the Pliocene. Supplemental data for this article is available online at https://doi.org/10.1080/11263504.2022.2036849. [ABSTRACT FROM AUTHOR]

Seagrass meadows have disappeared on many coastal sections due to anthropogenic disturbances, diseases, and/or eutrophication. To facilitate informed seagrass restoration, we i) quantified the hydrodynamic dislodgement thresholds for newly transplanted Z. marina shoots, and ii) tested the effect of artificial seagrass (ASG) as a hydrodynamic protection measure. Experiments were carried out by planting Z. marina rhizomes with living shoots into a sediment bed and exposing them to a range of wave and current conditions in a flume. The use of ASG significantly reduced wave height, as well as current velocity. The applied waves led to the development of ripples whereas currents led to erosion of the sediment bed. The number of shoots that were uprooted and dislodged increased with increasing bed shear stress and erosion. By reducing bed shear stress, the ASG raised the input current velocity threshold, which the transplanted shoots were able to withstand. The present study offers insight into the effect of artificial seagrass (ASG) on wave and current attenuation, as well as sediment erosion and shoot dislodgement. Our results help to inform the setting of hydrodynamic thresholds for the early establishment of Z. marina and to define the improvement of hydrodynamic conditions by ASG. [ABSTRACT FROM AUTHOR]

To assess the potential as carbon storages of short-life organisms in shallow coastal areas, refractory carbon fractions were examined using rapid biodegradation experiments. Refractory fractions of primary producers, such as seaweed and phytoplankton represented 31.2%−44.0% of the total carbon content. The seagrass Zostera marina contained a high rate of refractory carbon fraction, with 83.4% of the carbon in the belowground parts of Z. marina remaining as refractory carbon, which suggested that it had a significant function as a carbon storage in the shallow coastal area. The content of refractory carbon in the soft tissues of bivalves and gastropods were approximately 8.5%−31.5%, lower than that in other macrobenthos such as arthropods and echinoderms (29.7%−52.0%). The residual carbon in mollusk shells was mostly particulate inorganic carbon. In addition, 4.0%−19.1% of refractory organic carbon derived from polysaccharides and/or proteins in biominerals, while byssus remained. Considering the amount of shells in the shallow coastal zone, this organic carbon appeared to be a substantial carbon storage. Results suggested that not only primary producers but also macrobenthos and sessile animals have important carbon storage functions in coastal aquatic ecosystems. [ABSTRACT FROM AUTHOR]

Dreams provide a compelling problem for sensorimotor enactivists like Alva Noë: they seem to replicate our perceptual experiences without sensorimotor interaction with distal sensory stimuli. Noë has responded by saying that dreams actually fail to replicate perceptual experiences in virtue of their lack of detail and stability. Noë's opponents have replied by pointing out that some dreams are richly detailed and stable, and that instability and a lack of detail in dreams can anyway be explained in terms of the underlying neural activity. In this paper, I develop how the sensorimotor enactivist should respond: dreams fail to replicate perceptual experiences because they are exhausted by what shows up at a given moment in phenomenal consciousness, while perceptual experiences go beyond this to include everything accessible via sensorimotor exploration. This difference permeates all levels of experience, so that dreams can't even replicate perceptual experiences of simple shapes and colors. Further, unlike detail and stability, there are not obvious neural explanations of this phenomenal difference. [ABSTRACT FROM AUTHOR]

The present paper aimed to perform an environmentally friendly and effective study on the purification of biocidal material using bioremediation technique, and in this context, a natural widespread coastal biowaste (Zostera marina) was applied to remove a model biocide from aqueous system. Herein, malachite green was selected as a common agent to evaluate the biosorption efficiency of waste biomaterial. The bioremediation properties of biosorbent were studied in a controlled batch experiment system by the optimization practice of operating parameters like biosorbent quantity, medium pH, time, pollutant concentration and temperature, and kinetic, thermodynamic, equilibrium, and characterization operations. The optimum operating conditions were considered as 10 mg, 4, 6 h, 15 mg L−1, and 25 °C, respectively. Elovich and Langmuir were found to be the best-fitted models, describing the experimental biosorption data. Thermodynamic study revealed a favorable nature of the cleanup process. The characterization analysis indicated the presence of various functional groups on the layered biosorbent surface involved on the pollutant treatment. The untreated biosorbent showed a good biocide purification performance with a value of 97.584 mg g−1, and it could thus be employed as an eco-friendly and cost-effective cleaning agent in environmental bioremediation studies. [ABSTRACT FROM AUTHOR]

In the current study, we investigated the potential of Cronobacter sakazakii- ethylenediaminetetraacetic acid (EDTA) assisted phytoremediation potential of Zea mays L. to remediate lead (Pb)-contaminated soils. The C. sakazakii exhibited various stress tolerance mechanisms via plant growth promoting (PGP) traits, intrinsic extracellular enzyme production and antibiotic resistance. A greenhouse experiment was conducted to examine the dual effects of plant growth promoting endophytic bacteria (PGPEB)-chelator synergy in maize plants under different Pb contaminated soil regimes. C. sakazaii-EDTA (5 mM EDTA kg−1) complex significantly (p < 0.05) enhanced plant growth and biomass (48.91%); chlorophyll a, b and carotenoid contents (27.26%, 25.02% and 42.09%); relative water content (61.33%); proline content (63.60%); root and shoot Pb accumulation capacity (52.31% and 44.71%) in Pb contaminated soils. This may suggest the efficacy of current approach in enhancing plant tolerance capability toward Pb-uptake and phytoremediation capacity. Moreover, maize plants showed differential response to Pb availability in soil-1 (S1; Pb spiked soil, 500 mg kg−1) and soil-2 (S2; aged-contaminated soil) under various treatments. We describe the intriguing role of C. sakazakii-EDTA-maize system for Pb decontamination which can be used as a base line to explore the proposed combinatorial approach for long-term trails under field conditions for reclamation of Pb-contaminated soils. The PGPEB-EDTA mediated potential of Z. mays against Pb spiked and industrial contaminated soils is noticed. Increased tolerance of Z. mays against Pb in association with C. sakazakii, and EDTA is reported first time. Enhanced accumulation of metals by Z. mays is reported under combined treatment of C. sakazakii, and EDTA. Inoculation of plants with C. sakazakii, and EDTA has positive effects on growth and accumulation of Pb by Z. mays. [ABSTRACT FROM AUTHOR]

In this study, a novel biosorbent material was created from the waste product of Zostera marina with the surfactant modification (Hexadecyltrimethylammonium bromide) and tried as a potential alternative to commercial (powdered) activated carbon for the treatment of synthetic dye (Fast green FCF, triarylmethane (anionic) type) pollution in aquatic environment. The treatment capability of biosorbent material was evaluated by the parameter optimization, kinetic, thermodynamic, equilibrium and characterization experiments. The optimum treatment conditions were found to be pH of 3, biosorbent amount of 10 mg, synthetic dye concentration of 15 mg L−1, temperature of 45 °C and operation time of 360 min. It was determined that Elovich model was the most suitable model among the models used to define the biosorption kinetic data. The synthetic dye treatment process was endothermic and spontaneous. Freundlich model best explained the biosorption isotherm data. The biosorbent has very heterogeneous surface with the different functional groups. The treatment capabilities of prepared biosorbent and activated carbon under the same operating conditions were calculated to be 163.075 and 110.635 mg g−1, respectively. Hereby, these experimental findings show that the synthesized eco-friendly and low-cost biosorbent can be a powerful alternative to commercial activated carbon for the purification of synthetic dye pollution in water environment. [ABSTRACT FROM AUTHOR]

In this study, a renewable biosorbent material was prepared from biological waste of widespread coastal plant, Zostera marina and employed for the biosorption of heavy metal pollution from water environment in green way. Manganese was selected as a model heavy metal to evaluate the treatment efficiency of prepared biosorbent. The batch biosorption behavior of biosorbent was investigated by the characterization, parameters evaluation, kinetic and equilibrium studies. The characterization study showed that the biosorbent has a rough surface and various binding groups for the heavy metal ions. The heavy metal concentration of 30 mg L−1, time of 60 min, pH of 6 and biosorbent amount of 10 mg were determined as the optimum biosorption conditions. The pseudo-second-order equation was found to be the best among kinetic models applied. The equilibrium data were best explained by Freundlich isotherm. The maximum biosorption efficiency based on Langmuir model was predicted as 58.426 mg g−1. Hence, the current work presents a renewable alternative biosorbent substance for the green treatment of heavy metal pollution from water medium. [ABSTRACT FROM AUTHOR]

Within the scope of sustainable environmental remediation approach, a biosorbent prepared from the waste of Zostera marina coastal plant with chemical activation was used to effectively remove malachite green as a common biocidal agent from water environment in this work. The biocide treatment ability of activated biosorbent was interpreted through the characterization, optimization, equilibrium, thermodynamic, and kinetic studies. The characterization research showed that the biosorbent has an uneven surface and various active groups for the retention of biocide molecules. Langmuir isotherm was found to be the most appropriate model for the experimental equilibrium data. The maximum monolayer biosorption capacity was obtained as 103.834 mg g−1 under the optimum conditions (time of 6 h, pH of 4, temperature of 25 °C, biosorbent amount of 10 mg, and biocide concentration of 15 mg L−1). The biosorption system was determined to be spontaneous and exothermic in thermodynamic aspect. The experimental kinetic data were best described by the pseudo-second-order model. All these results indicated that the activated biological residue could be used as an environmentally friendly and effective biosorbent for the biocide removal from water environment in a sustainable way. [ABSTRACT FROM AUTHOR]

The recent world-wide loss of seagrasses, which are critical components of coastal ecosystems, has ignited an effort among scientists and resource managers to develop effective monitoring tools. Although Landsat time-series is considered one of the most cost-effective options for monitoring landscapes, its application to monitor seagrasses remains scarce due to many factors including difficulties obtaining accurate ground-truth data and perceived limitations in mapping nearshore marine ecosystems. Here, we report on the use of archived Landsat multispectral imagery and the automatic adaptive signature generalization (AASG) to evaluate eelgrass (Zostera marina) distribution and abundance between 1984 and 2017, in an estuary located in northeastern New Brunswick, Canada. The AASG algorithm, a novel cost-efficient approach for satellite imagery time-series analysis that requires limited ground truth data, was used to produce fourteen maps, four of which had accuracies ranging from 75 to 85%. The results indicated that eelgrass meadows near the beach barrier were highly dynamic, exhibiting high abundance fluctuations between years and a conversion of dense eelgrass to medium-low eelgrass near the main coastline. This study demonstrates the feasibility of using the AASG algorithm to map seagrass and advantages of including satellite time-series in monitoring programmes to investigate seagrass dynamics and long-term trends. [ABSTRACT FROM AUTHOR]

Quadrat sampling is one of the most widely accepted methods for conducting vegetation surveys over the world for centuries. However, it is difficult to determine an optimal size to adequately represent the community compositions in quadrat samplings. Traditional labour-intensive census-based quadrat sampling is also very time consuming and insufficient to represent spatial community characters outside of the quadrat extent. In order to improve the above deficiencies, an unmanned aerial vehicle (UAV)/red-green-blue (RGB) photography based vegetation survey methodology was proposed in this study. The essential steps in the proposed method include: 1) obtaining high spatial resolution optical images from the UAV; 2) extracting species based on the orthographic image after mosaic; 3) performing statistics on a given species within the image through different quadrat sizes; 4) determining an optimal quadrat size according to the changing trend of the statistical data. In addition, a case study applied this proposed methodology was conducted in a desert area in Northwest China, where Ammopiptanthus mongolicus and Zygophyllum xanthoxylon dominated. The results show that the remote sensing UAV method could obtain RGB images and orthoimage with flexible control. The statistical data of species density decreased with the increase of quadrat size, but the values changed slightly after 20 m × 20 m, which was larger than the typical quadrat size (10 m × 10 m) used to investigate shrubs. An analysis based on the relationship among species density, plants distribution, and quadrat size further indicated the reasonability of determining the optimal size. Based on the results, it is concluded that a minimum quadrat size of 20 m × 20 m should be adopted for investigating the density and spatial pattern characteristics of A. mongolicus and Z. xanthoxylon, and the proposed UAV-based method provides an alternative for vegetation survey with high efficiency and accuracy. [ABSTRACT FROM AUTHOR]

The correlation between anthocyanins content and accumulation of zinc (Zn) in leaves of Zea mays was investigated and this was considered as a mode of assessing the intensity of Zn toxicity. Characterisation and quantification of leaf pigments were done in 45 d old maize plants exposed to different concentrations of Zn (0.0, 0.65, 1.30, 1.95 g Zn Kg−1 soil), and the enhancement in the accumulation of anthocyanins and degradation of chlorophyll was detected by the spectral analysis performed in the leaf extract of plants as the Zn content in the shoot increases. The role of anthocyanins in safeguarding photosynthesis and chelation of Zn was critically evaluated using chlorophyll a fluorescence responses and computational DFT-B3LYP structural analysis of anthocyanins-Zn complex has been performed using 6-311++ G (df, p) basis set. It was concluded that the accumulation of anthocyanins can act as an indicator of the intensity of Zn stress and this anthocyanins have a lesser potential to maintain photosynthetic efficiency in Z. mays, but plays a prominent role in metal chelation as the anthocyanins-Zn complex is a stable molecule. [ABSTRACT FROM AUTHOR]

In developing countries, Cd contamination is ubiquitous which limits agriculture productivity. The current study was designed to investigate the efficacy of plant—Bacillus pumilus—ethylene diamine tetraacetic acid (EDTA) and plant-microbe-chelator (PMC) synergy for enhanced plant growth and Cd-uptake potential of Zea mays in industrially contaminated and cadmium (Cd) spiked soil. A pot experiment was conducted by growing Z. mays seedlings either inoculated with B. pumilus or un-inoculated along with the application of 5 mM EDTA. Plants were exposed to two levels of Cd contamination for 45 days. An increase in Cd uptake was observed in Z. mays inoculated with B. pumilus followed by EDTA treatment as compared to non-inoculated and un-treated ones. Zea mays showed improved values with PMC approach for different growth parameters including root length (41%), shoot length (40%), fresh weight (59%), dry weight (49%), chlorophyll contents (49%), and relative water contents (30%). Higher tolerance index (117%) was observed for plants grown in soil spiked with 300 mg kg−1 Cd (S2). PMC application markedly enhanced Cd uptake potential of Z. mays up to 12% and 68.8%, respectively, in S1 and S2 soil. While the PMC application increased Cd accumulation capacity of Z. mays by 71.2% and 52.5% in S1 and S2 soil. The calculated bioaccumulation and translocation factor revealed that Z. mays possess Cd uptake potential, and this ability can be significantly enhanced with PMC application. First synergetic plant-microbe chelator (PMC) green technology for Cd-decontamination. Endophytic strain Bacillus pumilus 18a exhibited PGP traits. B. pumilus-EDTA complex improved plant biomass, tolerance index and phytoextraction efficiency. Zea mays L. act as Cd-accumulator under aged and spiked Cd contaminated soil. More Cd2+ retention in root than shoot was observed. [ABSTRACT FROM AUTHOR]

Rapid growth of the urban population, particularly in developing countries, places an enormous pressure on water. Sewage farming is common in all urban areas in India. This study is an attempt to evaluate the effect of diluted sewage wastewater irrigation on cultivation of Eleusine coracana and Zea mays from selected semi-urban and rural areas of Coimbatore, Tamil Nadu. For this, parameters analyzed were water/soil quality, crop quality, and mineral analysis including heavy metal composition and in vitro antioxidant potential. From the results, the physicochemical parameters of both rural and semi-urban wastewater samples are within the permissible limits according to the WHO. In mineral analysis, the heavy metals such as Pb, Fe, and Zn are high in all samples and Ni, Cr, and Cu are within the permissible limits in rural samples but slightly high in semi-urban samples. The proximate composition provides general overview of the nutritional value of a food. E. coracana and Z. mays samples collected from rural area show adequate mineral profile required for growth and nutrition. Both the samples show significant antioxidant values significant at p < 0.05. The results demonstrated that the diluted sewage wastewater has physicochemical properties for safe irrigation. Micronutrient and heavy metal contents in the plant samples were not extremely high and were within the range of FAO/WHO standards. [ABSTRACT FROM AUTHOR]

Eelgrass (Zostera marina L.) is a marine angiosperm plant that grows throughout coastal areas in Atlantic Canada. Eelgrass meadows provide numerous ecosystem services while they have been acknowledged as important habitats, their location, extent, and health in Atlantic Canada are poorly understood. This study examined the effectiveness of WorldView-2 optical satellite imagery to map eelgrass presence in Tabusintac, New Brunswick, an estuarine lagoon with extensive eelgrass coverage. The imagery was classified using two supervised classifiers: the parametric Maximum Likelihood Classifier (MLC) and the nonparametric Random Forest (RF) classifier. While RF was expected to produce higher classification accuracies, it was shown not to be much better than MLC in this particular context. The overall validation accuracy was 96.36% for both the RF and MLC classifiers. Finally, the comparison of our 2014 classified image with a 2008 eelgrass distribution map shows an increase in eelgrass extent in the bay between both years. [ABSTRACT FROM AUTHOR]

Zingiber zerumbet (L.) Roscoe ex Sm. (family-Zingiberaceae) is an important medicinal herb. Though rhizome extract of this species has been used in traditional herbal medicine across the globe for the treatment of numerous diseases like worms, cough, leprosy, asthma and other skin diseases, the composition of the extract is not characterised properly till date. Thus, acetone extract of Zingiber zerumbet rhizome was subjected to Gas Chromatography-Mass Spectrometry (GC/MS) to analyze the phytoconstituents. A total of nine compounds were obtained out of which zerumbone was found to be the major constituent covering 64.58 % of the total area. Beside zerumbone, other important compounds like diacetone alcohol (10.64 %), α-humulene (8.93 %), caryophyllene oxide (5.68 %), humulene epoxide (3.18 %), Eudesm-7(11)-en-4-ol (2.87 %), aromadendrene oxide (1.98 %) were also found in the tested extract with some other compounds in trace amount. Among the compounds, terpenes were found to be the primary constituent of the extract. This finding revealed the presence of the high amount of terpenes in the rhizome of Z. zerumbet for the first time. The study indicated that Z. zerumbet is a good source of sesquiterpenes and oxygenated sesquiterpenes which can be used at industrial level for the production of pharmaceuticals, perfumes and flavouring agents. [ABSTRACT FROM AUTHOR]

Parthenium hysterophorus is an invasive weed that poses significant threats to crop production, biodiversity, human and animal health. Few experiments have been carried out to test the effectiveness of biological control agents such as the beetle Zygogramma bicolorata against this invasive. We released Z. bicolorata beetles as bio-agent to control P. hysterophorus at the Tropical Pesticides Research Institute in Arusha, Tanzania, across two seasons, from February – July 2019 (wet) and August 2019 – January 2020 (dry). Feeding by Z. bicolorata reduced P. hysterophorus leaves, flowers, height as well as biomass, both in the dry and wet season. During the wet season, 100% of all P. hysterophorus leaves were eaten already 28 days after the onset of the experiment, particularly under the highest beetle population treatment (30 individuals). Parthenium hysterophorus flower numbers were greatly reduced under high beetle populations (30 individuals) compared to the control treatment (0 individuals) during both the wet and dry season. Parthenium hysterophorus height was reduced by 87% and 90% during the wet and dry season, respectively when 30 beetles were released. Similarly, biomass was reduced by 90% and 87% during the wet and dry season, respectively. Parthenium hysterophorus responses to beetle treatments did not differ significantly across seasons but the development of both the invasive and its control, Z. bicolorata, was slightly delayed in the dry season. We conclude that Z. bicolorata can be used as bio-agent to manage P. hysterophorus in Tanzania, particularly when released in large numbers. [ABSTRACT FROM AUTHOR]

is a canopy-forming brown seaweed distributed along the western Mediterranean and the adjacent Atlantic coasts, which has suffered massive declines in recent decades, particularly in the Canary Islands. Here, we describe seasonal variation in the canopy structure of this alga, addressing the role of environmental drivers. Four sites around the island of Gran Canaria were investigated monthly during an entire annual cycle. Annually, the non-fertile stage made up the majority of populations, in terms of frond density, while the fertile stage was comparatively sparser. This fertile stage, however, had the largest biomass and reached the longest lengths, showing significant seasonality. Best fitted GAM models included wave action, PAR and seawater temperature, but only accounted for a moderate variation in the seasonal frond structure of this alga. Total frond biomass, mostly fertile fronds, showed a bimodal pattern, with a peak in spring and a less accentuated peak in late summer–early autumn. This pattern was particularly obvious at sites with a wide annual variation in wave action, with lower biomass at times of high wave action. The frond size-structure was dominated, at all sites and times, by small fronds. The high frond density seems to promote intraspecific facilitation throughout the year. These results provide fundamental knowledge to improve the conservation and potential restoration actions for endangered populations of this alga. [ABSTRACT FROM AUTHOR]

Subtidal habitats have not yet been accounted for in habitat maps of South African estuaries. In this study, a novel method for mapping subtidal estuarine habitats, using a remotely operated underwater vehicle (ROV) piloted from a boat, was developed and tested in the Knysna Estuary. Video footage was recorded along 48 transects across the width of the estuary, and then reviewed to identify, classify and map habitats. Using the method developed in this study, 21 hours of footage was recorded over 15 days of sampling, and about 30 hours of post-processing was carried out to map an area exceeding 850 ha. This study has produced the first baseline dataset of subtidal habitats for a South African estuary. Additionally, the study revealed the previously unknown distribution of the invasive red seaweed Asparagopsis taxiformis, and the underestimation in previous studies of the estuary of area cover of eelgrass Zostera capensis by 130 ha. [ABSTRACT FROM AUTHOR]

A novel biosorbent was prepared by the surface modification of Zostera marina L. bioresidues and used for the removal of model synthetic dye, methylene blue from aqueous medium in this study. Taguchi design of experiment (DoE) methodology was employed to investigate the influence of significant operational parameters (reaction time, pH of medium and dye concentration) on the biosorption process and to develop a mathematical model for the estimation of biosorption potential of biosorbent. The percentage contribution of each of these process variables on the dye biosorption was found to be 9.03%, 1.95% and 88.84%, respectively. The dye biosorption capacity under the obtained optimum environmental conditions (reaction time of 120 min, pH of 8 and dye concentration of 15 mg L−1) was estimated to be 140.154 mg g−1 (R2: 99.83). This value was very close to the experimentally obtained dye removal performance value (140.299 mg g−1). These findings indicated the high ability of Taguchi DoE technique in the optimization and simulation of dye biosorption system. The kinetic and equilibrium modeling studies showed that the pseudo-second-order and Langmuir models were the best models for the elucidation of dye removal behavior of biosorbent. Besides, the performance of dye decontamination system was evaluated using the pseudo-second-order kinetic parameters. The thermodynamic analyses displayed that the dye biosorption was a feasible, spontaneous and exothermic process. For large scale dye purification applications, a single-stage batch biosorption system was also designed using the mathematical modeling data. All these results revealed that Z. marina L. bioresidues could be used as a promising alternative biosorbent material for the effective and eco-friendly dye biosorption systems. [ABSTRACT FROM AUTHOR]

Passive acoustic recordings were made at two sites over a four-month period in eelgrass beds in a shallow estuary (Shinnecock Bay, New York, USA). Recordings were dominated by mating calls of striped cusk eels (Ophidion marginatum) at one site, and oyster toadfish (Opsanus tau) mating calls at the other. Cusk eel call characteristics (frequency and pulse period) varied significantly with time and water temperature. Fundamental frequency of toadfish calls decreased over the recording period and was not correlated with water temperature. We developed and tested automated detection algorithms to identify choruses using band-limited sound pressure levels. Distinct diel peaks in sound production were observed, with cusk eels producing morning and evening choruses, and toadfish calling mostly during daytime. Several physical and environmental variables were significantly correlated with the presence of cusk eel and toadfish choruses such as water temperature, tide state, and moon phase. The temporal variation in sound production and call characteristics differed from other studies, suggesting geographical variations in the acoustic behaviour of both species. Passive acoustic techniques can identify the location and timing of reproductive events for cryptic species that live in shallow water (<2 m) habitats, which are critical information for identification of their habitat. [ABSTRACT FROM AUTHOR]

Parthenium hysterophorus L. (Asteraceae) is an alien herbaceous weed with a pantropical distribution. The weed adversely affects grazing land productivity, native biodiversity and causes respiratory and dermal allergies in humans. The weed continues to invade new countries, with increases in CO2 set to further enhance this spread. Biological control is among the most cost-effective management strategy for P. hysterophorus, with the leaf-feeding beetle Zygogramma bicolorata Pallister (Coleoptera: Chrysomelidae) among the most promising candidates. Our review discusses the life cycle and feeding and reproductive behaviours of Z. bicolorata. We emphasise how abiotic factors and biological processes, viz. ageing, rhythmicity, multiple matings and interactions amongst species, influence the fertility and mortality parameters of the beetle. We anticipate that this review will assist in improving the strategies for rapid mass-multiplication of Z. bicolorata in laboratories. In addition, the review will support efforts to develop classical biological control approaches in regions where Parthenium is invasive. [ABSTRACT FROM AUTHOR]

The genus Vigna contains important crops such as cowpea and mungbean. Wild Vigna showing higher salt tolerance than Vigna crops were screened and their tolerance mechanisms are discussed. Primary screening using 7 Vigna crops and 23 wild Vigna under 300 mM NaCl selected V. luteola, V. marina and V. vexillata. A study under different salt concentrations revealed the highest survival ability of V. marina. Diversity of salt tolerance in each species was revealed using a total of 230 accessions. Growth and physiological responses under 150 mM NaCl were then compared using two selected accessions from each species. The pattern of Na+ accumulation in roots, stems and leaves suggested that V. vexillata (V1) and V. luteola (L8, L9) are 'Na+ excluder' type, while V. marina (M1, M4) is 'Na+ includer' type. V. luteola (L8, L9) showed the highest dry matter production under control condition and well-maintained shoot dry weight under salt stress. Interestingly, V. luteola (L9) accumulated the highest Na+ in roots (3000 μM g−1) and increased root dry weight under salt stress, which might work as Na+ reservoir restricting Na+ transition to the leaves, leading to the increased photosynthetic rate. V. luteola has great potential in areas where moderate salt damage occurs. V. marina (M1, M4) accumulated Na+ at high level in roots, stem, and leaves. Under salt stress, they increased stomatal conductance, transpiration rate, and photosynthetic rate, which suggested the adaptational regulation of aquaporin gene expression. V. marina will be useful as food, pasture and phytoremediation legumes in highly salt-damaged areas. [ABSTRACT FROM AUTHOR]

Antioxidant enzymes are essential proteins that maintain cell proliferation potential by protecting against oxidative stress. They are present in many organisms including harmful algal bloom (HAB) species. We previously identified the antioxidant enzyme 2-Cys peroxiredoxin (PRX) in the raphidophyte Chattonella marina. This enzyme specifically decomposes a hydrogen peroxide (H2O2). PRX is the only antioxidant enzyme so far identified in C. marina. This study used mRNA-seq, using Trinity assemble and blastx for annotation, to identify a further five antioxidant enzymes from C. marina: Cu Zn superoxide dismutase (Cu/Zn-SOD), glutathione peroxidase (GPX), catalase (CAT), ascorbate peroxidase (APX) and thioredoxin (TRX). In the gene expression analysis of six enzymes (Cu/Zn-SOD, GPX, CAT, APX, TRX and PRX) using light-acclimated (100 μmol photons m−2 s−1) C. marina cells, only PRX gene expression levels were significantly increased by strong light irradiation (1000 μmol photons m−2 s−1). H2O2 concentration and scavenging activity were also increased and significantly positively correlated with PRX gene expression levels. In dark-acclimated cells, expression levels of all antioxidant enzymes except APX were significantly increased by light irradiation (100 μmol photons m−2 s−1). Expression decreased the following day, with the exception of PRX expression. With the exception of CAT, gene expression of antioxidant enzymes was not significantly induced by artificial H2O2 treatment, although average gene expression levels were slightly increased in some enzymes. Thus, we suggest that light is the main trigger of gene expression, but the resultant oxidative stress is also a possible factor affecting the gene expression of antioxidant enzymes in C. marina. [ABSTRACT FROM AUTHOR]

Ecological restoration of many arid zones is a pressing issue because of recurrent loss of plant cover. Here, we conducted a germination and growth study of three framework plant species, native to the Chihuahuan Desert in Northern Mexico, to optimize the establishment for arid zone restoration. The plant species were Zinnia grandiflora Nutt., Menodora scabra A. Gray, and Yucca elata (Engelm.) Engelm, which were selected for their potential for restoration as drought tolerant species. We evaluated seed germination, survival, and biomass allocation of seedlings under four (high, medium, low, and very low) simulated rainfall sequences as irrigation treatments. Rainfall sequences were obtained from a previous study that considered 35 years of precipitation records. Each sequence is accounted for 20% of probability of a wet, normal, low, or very low year in terms of precipitation occurring in the study area. Germination was conducted in controlled greenhouse conditions and seeding was done in pots containing soil mix. Sequences produced soil moisture fluctuations in which germination percent was higher for M. scabra (88%) and Z. grandiflora (31%) on the high sequence compared to the other sequences. Survival at the end of the treatments was above 80% of all the three species, and seedlings allocated more aboveground biomass as the moisture increased and more belowground biomass as moisture decreased. Implications under our study conditions include that germination of Y. elata would not be negatively affected by low soil moisture, and the best germinative results for Z. grandiflora and M. scabra would be achieved under higher soil moisture. [ABSTRACT FROM AUTHOR]

Temporal changes of algicidal and growth-inhibiting bacteria on the fish-killing raphidophyte flagellate, Chattonella antiqua, at an eelgrass (Zostera marina) bed in southern Ariake Sea, Japan in 2011 was investigated. The maximum value (5.1 × 107 CFU g−1 wet leaf) of algicidal bacteria (AB) was detected from a biofilm formed on Z. marina on August 1 when AB in the adjacent seawater had also peaked (1.2 × 104 CFU mL−1). Two causative bacteria isolated from the biofilm and seawater on August 1 were both identified to be of the genus Alteromonas (γ-proteobacteria). AB and growth-inhibiting bacteria (GIB) were present from the beginning of sampling (May 20) to August 26, fluctuating between 8.6 × 102 and 1.2 × 104, 1.2 × 103 and 9.3 × 103 CFU mL−1, respectively. The highest phytoplankton density observed was 6423 cells mL−1 on September 29 and was comprised of centric diatoms such as Chaetoceros, Skeletonema, and Thalassiosira and coincided with the absence of AB and GIB where the decline of Z. marina was also observed. These findings provide a new ecological insight on AB and GIB associated with Z. marina beds, indicating eelgrass beds have the important role as the nursery of those bacteria that can be utilized as mitigation measures of harmful algal blooms (HABs) in the future. [ABSTRACT FROM AUTHOR]

A bioassay-guided approach was used to identify defense compounds that are present on the surface ofZostera marinaand which inhibit settlement of microfoulers at natural concentrations. Moderately polar eelgrass surface extracts inhibited the settlement of seven marine bacteria and one yeast that originated from non-living substrata. In contrast, five other bacterial strains that had been directly isolated from eelgrass surfaces were all insensitive, which suggested a selective effect of surface metabolites on the microbial communities present on eelgrass. Bioassay-guided isolation of active compounds from the extracts in combination with UPLC-MS and1H-NMR spectroscopy resulted in the identification of rosmarinic acid, luteolin-7-sulfate and diosmetin-7-sulfate or its isomer chrysoeriol-7-sulfate. All three compounds are nontoxic repellents, as they did not inhibit bacterial growth, but prevented bacterial settlement in a dose-dependent manner. Between 15.6 and 106.8 μg ml−1of rosmarinic acid were present on the eelgrass surface, enough for half maximal settlement inhibition of bacteria. [ABSTRACT FROM AUTHOR]

Many studies have shown that natural marine compounds can prevent biofouling by a broad spectrum of organisms without toxic effects, encouraging their use in antifouling (AF) coatings. Studies over the past 25 years of the natural product zosteric acid (ZA) are systematically organized in this review. ZA is a sulfated phenolic acid produced by the seagrassZostera marinathat has very promising AF potential against several micro- and macrofouling organisms. ZA was shown to have appropriate environmental fate parameters such as high water solubility, a low logP, low bioaccumulation, and no ecotoxicity, which demonstrated the potential of ZA as a safe AF agent. This review also highlights that ZA has been successfully incorporated into several types of coatings. The synthesis of analogs is also considered in this review, and it has allowed a better understanding of ZA structure–AF activity relationships and clarified the mechanism of action of ZA. [ABSTRACT FROM AUTHOR]

The consequences of physical disturbances to seagrasses depend on disturbance frequency relative to the capacity for recolonization and recovery following fragmentation. In a subtidal seagrass meadow of Zostera marina L., following a season of clam harvesting, we compared the temporal change of shoot density and biomass of this seagrass together with the community structure of the associated macroinvertebrates, at two sites differing in the intensity of the physical disturbance. The impacted site showed significantly lower shoot density and total biomass than the non-impacted site initially. The increase in above-ground biomass over four months (May to September) of this species was significantly higher (46%) at the impacted site than in the area not affected by the disturbance. Four months after cessation of the extraction activity, the biomass and density values of Z. marina reached similar values to those measured in the non-impacted site. The sexual reproductive effort of the seagrass population affected by the disturbance (4%) was significantly lower than at the non-impacted site (10%), which could influence genetic diversity and the seed bank. The community structure of molluscs showed 54% similarity between sites at the beginning of the study. Four months later, mollusc communities increased to a similarity of 74%. The current closure season (four months annually) established for the recovery of the exploited stocks of bivalves allowed the recovery of Z. marina density and biomass. Nevertheless, other population properties, such as those related to reproductive patterns, remained altered by the disturbance. [ABSTRACT FROM AUTHOR]

Eelgrass meadows are a common feature in shallow waters along the Norwegian coast, where they provide a habitat for a diverse infaunal community. Recreational boat anchoring and moorings physically scour seagrass and may affect the ecosystem functioning and resilience of the system to natural and anthropogenic disturbances. A small-scale eelgrass (Zostera marina) removal experiment was conducted to study the effects on macro- and meiofauna. Entire plants, including the rhizomes, were removed from 4 m2patches in three eelgrass meadows in the inner Oslofjord in October 2010. Core samples were taken after a recovery period of 10 months, from the removed patches as well as from the surrounding meadow. Macrofauna (>500 μm) and meiofauna (63–500 μm) in the sediment were investigated for possible effects of the eelgrass removal. Macrofauna and meiofauna composition were site specific and therefore location was identified as the main determinant for the infaunal community. The eelgrass did not regrow within the recovery period and bare sediment patches with only single eelgrass shoots were present during the sampling. Our analyses support an influence of the removal on individual species, but not the complete community. In particular one species, the gastropodPeringia ulvae, was encountered in higher numbers in samples from the removed patches than in control samples. From a management perspective, such minor removal of eelgrass, on the scale of square metres, appears to have no long-lasting detrimental effect to the infaunal community in sheltered meadows with muddy sediments. [ABSTRACT FROM PUBLISHER]

Copper (Cu2+) is an essential nutrient for plants but toxic at high concentrations. We subjected seedlings and young plants of eelgrassZostera marinato different seawater Cu concentrations (3, 4, 5, 10, 30 and 50 µg l−1) for over 30 days under controlled laboratory conditions. Natural seawater without added Cu (3 µg l−1) was used as reference seawater. We measured plant response in terms of survivorship, morphology, growth, productivity and leaf pigment concentration. Survival analysis combined with morphological, dynamic and productive assessment suggested that the optimum seawater Cu concentration for the establishment ofZ. marinaseedlings and young plants is 4 μg l−1. The photosynthetic response of young plants to copper enrichment, including an increase in chlorophyll content under low Cu concentration treatment but significant decrease when treated with high concentrations of Cu, is similar to those reported for other seagrass species. NOEC (no observed effect concentration), LOEC (lowest observed effect concentration) and LC50(lethal concentration that caused an increase in mortality to 50% of that of the control) values of seedlings were significantly lower than those of young plants, implying a reduced Cu tolerance to high concentrations (>10 μg l−1). This study provides data that could prove helpful in the development of successful eelgrass restoration and conservation. [ABSTRACT FROM AUTHOR]

This study provides novel information regarding the length–weight relationships (LWRs) and reproductive characteristics of the crowned seahorse (Hippocampus coronatus) living along the southern coast of Korea. Specimens of H. coronatus were collected from an eelgrass bed in Dongdae Bay, Korea, during September 2006–August 2007. In total, 133 specimens were collected (76 females, 57 males) and their lengths ranged from 2.41 to 9.31 cm and 2.41 to 9.32 cm for females and males, respectively. No significant difference was observed between the sex ratio of specimens collected in this study and the theoretical 1:1 ratio (χ2-test, P > 0.05). All LWRs were highly correlated (r2 > 0.941, P < 0.001), and the overall slopes of the length–weight regressions were 3.067 for females, 2.808 for males and 2.955 for both sexes. Size at first sexual maturity was 6.93 and 7.33 cm in length for females and males, respectively. Monthly changes in the gonadosomatic index (GSI) indicated that the spawning period was from June to November. Total number of eggs ranged from 56 to 163 with mature eggs from 4 to 56, and the number of brood in the pouches of males ranged from 12 to 46. [ABSTRACT FROM AUTHOR]

We subjected young, seed-generated plants ofZostera marinaLinnaeus, 1753 to different light intensities (0, 4, 10, 25, 130, 195, 327 and 373 µmol m−2s−1, in sunlight) for over 30 days under controlled laboratory conditions. The light treatments were categorized into four light levels, namely, 0 µmol m−2s−1; below compensation point (BCP; 4, 10, 25 µmol m−2s−1); saturation light (SL; 130, 195 µmol m−2s−1); and above saturation (AS; 327, 373 µmol m−2s−1). We measured plant response in terms of survivorship, morphology, growth, and leaf pigment concentration. The survival rate of young seedlings exposed to 0 µmol m−2s−1was significantly lower at 23.3% compared with seedlings under other light intensities, whose survival rates were above 60%. The leaves of the seedlings under 0 µmol m−2s−1and AS level became partially brown and wilted after 30 days. Morphological analysis combined with dynamic assessment suggested that the optimum light intensities for the growth of youngZ. marinaseedlings are from 130 to 195 µmol m−2s−1within the SL level. The physiological photoadaptive responses of the seedlings to light reduction, including an increase in chlorophyll content and a decrease in the chlorophylla:bratio, are similar to those of matureZ. marina. This study will further develop our understanding of the physiological ecology of young seedlings of this species and provide data that could prove helpful in the development of successful eelgrass restoration techniques involving early life stages. [ABSTRACT FROM PUBLISHER]

We used expert elicitation to examine potential responses of eelgrass to several restoration strategies in Puget Sound. Restoration strategies included shoreline armor removal and modification, removal and modification of overwater structures, and efforts to improve water clarity via reductions in anthropogenic nutrient and sediment loadings. Expert responses indicated a general belief that reducing stressors would increase eelgrass cover; however, responses varied greatly among stressors. Our analyses revealed that removal of overwater structures, nutrient loading and shoreline armoring will have significantly larger effects on eelgrass recovery than would removal of sediment loading, with removal of overwater structures having the largest effect. We then used a probabilistic model to estimate what actions, singularly or in combination, could yield a large increase in eelgrass cover. Reducing single stressors could, in theory, result in recovery of eelgrass in Puget Sound; however, the magnitude of actions required would be so great that it is likely not practical. In contrast, we identified combinations of smaller reductions of stressors that could achieve significant eelgrass recovery. For example, a 40% reduction in overwater structures, combined with 20% reductions in shoreline armor, and nutrient and sediment loadings, was predicted to be one of the more feasible combinations of actions for meeting the target. The importance of eelgrass to Puget requires prompt input of scientific advice, and this work fills an important knowledge gap in the face of rapidly approaching legislative deadlines. While coded expert opinion of the sort we use here is a weak substitute for data, our work clarifies the current extent of scientific uncertainty that can guide management action in the near term and scientific research in the long term. [ABSTRACT FROM PUBLISHER]

Most mobile animals rely on orientation cues for either long-distance migration or to move shorter distances on a daily basis. Supratidal amphipods in the northern Gulf of Mexico regularly use orientation cues in both water and on dry sand to return to their home in seagrass wrack. I manipulated the presence of visual and magnetic cues in both water and sand. Visual cues were important for orientation in water, but magnetic cues were important on dry sand. The use of orientation cues by amphipods is context-dependent and suggests that some cues may be more reliable in different environments. Casey P. terHorst is now at Kellogg Biological Station, Michigan State University, Hickory Corners, MI, USA. [ABSTRACT FROM PUBLISHER]

To investigate the importance of benthic vegetation for shallow infaunal assemblages, macroinvertebrates were sampled inZostera marina meadows and in adjacent bare sand at three sites in the Skagerrak region and one in the Western part of Norway. A total of 3777 individuals were encountered, representing mainly the faunal groups Annelida, Nemertea, Echinodermata, Crustacea and Mollusca. Twice as many individuals were found in theZ. marina meadows compared to the bare sand. Oligochaetes were the most abundant group (29% of total number of individuals), followed by crustaceans (24%), polychaetes (18.5%) and molluscs (16%). Polychaetes showed the highest species number (42), followed by molluscs (30) and crustaceans (26). Multivariate cluster technique showed the highest similarities within sites and thereafter grouping according to the two different habitats;Zostera and sand. No regional differences were evident between the Skagerrak sites and the site in Western Norway, as the site from Western Norway grouped together with one of the Skagerrak sites. The high biodiversity inZostera marina beds should have implications for the management of such areas. [ABSTRACT FROM AUTHOR]

Stuckenia pectinata is widely distributed submerged macrophyte in the world. Herein, the complete chloroplast genome of this species was assembled and characterized using whole genome next-generation sequencing. The complete chloroplast genome showed a circular genome of 156,669 bp size with 36.5% GC content. The genome is of typical structure and contain a pair of inverted repeat (IR) regions with 26,074 bp, separated by one large single-copy (LSC) with 86,285 bp, and one small single-copy (SSC) regions with 18,236 bp. De novo assembly and annotation showed the presence of 131 unique genes with 85 protein-coding genes, 38 tRNA genes, and eight rRNA genes. A maximum-likelihood phylogenomic tree reconstructed based on 15 chloroplast genomes reveals that S. pectinata is most closely related to Zostera marina. [ABSTRACT FROM AUTHOR]

Ruppia is widely distributed in marine and inland saline habitats in temperate and tropical regions. In this study, the complete chloroplast genome sequence of R. sinensis was successfully obtained using Illumina sequencing. The full length of the chloroplast genome length was 158,897 bp with a typical quadripartite structure: one large single copy (LSC) region (88,952 bp), one small single copy (SSC) region (19,047 bp), and a pair of inverted repeats (IR) (25,449 bp each). The GC content of this genome was 35.9%. The whole genome contained 136 genes, including 88 protein-coding genes, 40 tRNA genes, and eight rRNA genes. Phylogenetic analysis indicated that R. sinensis formed a distinct clade, being separated from Zostera marina and Potamogeton perfoliatus. [ABSTRACT FROM AUTHOR]

In this article we describe an instance of free-choice learning in the context of an eelgrass mapping and stewardship project (the Project) that covers over 500 kilometers of coastline in British Columbia, Canada, and involves 20 volunteer groups. In this ethnographic case study we sought to (a) explicate the relationship between individual and collective learning in this free-choice setting and (b) understand how a network of Project participants could both constitute a free-choice learning setting and support such a setting. We articulate a dialectic relationship between individual and collective learning, which, unfortunately in our view, has not yet been explored in educational research. In this relation, collective learning fosters individual learning and vice versa, whereby individuals produce resources in action and as outcomes of their activities. These resources expand the action possibilities of the collective, and thus constitute learning. The stability of the network of Project participants, which brings about and supports collective and therefore individual learning, rests on the flexibility of the Project that enables local innovation and tailoring of mapping activities as well as access to expertise and tools produced by other groups and Project partners. The possibilities that arise in the Project for local people to participate in relevant ways constitute free-choice learning settings. [ABSTRACT FROM AUTHOR]

The macrophytes Fucus serratus and Zostera marina form similar substrates for associated flora and fauna in shallow waters in Norway. While F. serratus forms a more or less continuous belt on rocky substrate along the coast, Z. marina forms disjunct populations on sandy or muddy bottoms. This study focused on the organisms associated with these two macrophytes in two localities in the Skagerrak region. In total, 130 taxa of epiphytic organisms were identified: 22 green algae, 41 red algae, 32 brown algae, eight diatoms and 27 sessile animals. One hundred and twenty-seven taxa of mobile macrofauna were registered. The dominant group was crustaceans, with amphipods as the order containing most species. Many species of both plants and animals preferred one or the other habitat. It is concluded that coastal macrophyte systems have high species diversity. [ABSTRACT FROM AUTHOR]

The number of microorganisms in the hindgut of dugongs ( Dugong dugon ) were estimated and their in vitro volatile fatty acid (VFA) production and degradation of eelgrass measured. Scanning electron microscopy showed that some rod bacteria attached to the surface of plant tissue degraded and eroded the cell walls. Number of starch-, lactate-, cellobiose-, pectin-, xylan- and cellulose-utilizing bacteria, sulfate-reducing bacteria and methane-producing bacteria were estimated at 10 9 ∼ 10 10 colony forming units g -1 . Microorganisms degraded the cellulose and noncellulolytic components of the eelgrass, and about 47.3% of dry matter was degraded after 36 h in vitro incubation. The total VFA concentration was 10.5 mmol dL -1 at 36 h incubation, which included 55.7 mol% acetate, 18.0 mol% n -butyrate and 15.1 mol% propionate. The gas composition of in vitro fermentation was 68.4% carbon dioxide, 22.2% methane and 9.4% hydrogen. [ABSTRACT FROM AUTHOR]

Food consumption and digestion of male and female dugongs ( Dugong dugon ) was examined by analyzing long-term (1979-1998) feeding records at Toba Aquarium (Japan). Throughout all captive feeding periods, dugongs consumed eelgrass ( Zostera marina ) and showed steady increases in feed consumption with a consistent weight gain of 42-45 kg a year. The daily consumption of male and female dugongs increased from 10-15 kg to 23-26 kg of fresh eelgrass, accounting for approximately 14 and 7% of their body weight at one and seven years old, respectively. Both dugongs had a marginal dry matter digestibility of over 90%. Food consumption varied between seasons and individuals. There were major reductions ( P <0.05) in consumption by the male in November and January and by the female in August and September. The seasonal reductions in food consumption coincided with high digestibility of eelgrass. [ABSTRACT FROM AUTHOR]

Deterioration of an eelgrass ( Zostera marina ) bed was observed in Skagerrak, southern Norway in August 2002. Compared with observations from previous years, there was a significant reduction in canopy height and shoot density. Simultaneously, high numbers of the gastropod Rissoa membranacea were observed. The proposed mechanism for this drastic loss of eelgrass leaves involves epidermal injuries caused by the grazing activity of the numerous snails, with subsequent leaf breakage. After 1 year, the canopy height had recovered, but shoot density was at the same level as in 2002. [ABSTRACT FROM AUTHOR]

Samples of Musculista senhousia , 20 mm in length, were gathered from San Diego Bay and fed on three different food concentrations: 0.2, 0.4 and 0.8 mg AFDW L -1 , and their energy balance studied. Food concentration ranges were selected to reflect those observed in the field where the invasive mussel M. senhousia co-occurs with the angiosperm, Zostera marina . The lowest and intermediate concentrations correspond to concentrations described in and over large eelgrass patches, respectively. The upper concentration is equivalent to that occurring during the spring phytoplankton blooms. Ingestion rates varied between 81.6 µg AFDW h -1 for the mussels fed on the lowest concentration, 191.2 µg AFDW h -1 when the concentration rose to 0.4 mg AFDW L -1 , and 164.0 µg AFDW h -1 for the highest concentration. Food concentration had a significant effect on absorption efficiency, which was approximately 70% at the intermediate and upper concentrations, but rose to over 80% at the lowest concentration. The food absorption rate varied with food concentration in a manner similar to that of the ingestion rate, i.e., with a maximum value of 142.34 µg AFDW h -1 for the mussels fed on the intermediate concentration, this being higher than the values for both the highest concentration (114.72 µg AFDW h -1 ) and the lowest (65.89 µg AFDW h -1 ). Respiration rates were 54 µg O 2 h -1 for the mussels fed on the lowest concentration and 74 µg O 2 h -1 for those fed on the intermediate concentration. These results show a close relationship between respiration and ingestion rates, which can be fitted to the following equation: RR = e (-0.42 + 0.10 IR) ( r = 0.5703, R 2 = 32.53, p <0.01). Scope for growth (SFG) estimations were higher for those mussels fed at the intermediate and upper concentrations (1.95 J h -1 and 1.50 J h -1 , respectively), between which no significant difference was observed ( p > 0.05), whilst SFG for the lowest food concentration was only 0.69 J h -1 . The physiological rate with the greatest effect on growth was the absorption rate. Its relation to SFG is described by the equation SFG = 0.67 + 0.90AR ( r = 0.977, R 2 = 95.56%, p <0.01). The discussion of these results is based on the growth rates that have been described for this mussel in its natural environment where habitat structure, such as the canopy provided by the eelgrass, can affect the success of the invasive mussel. [ABSTRACT FROM AUTHOR]