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Sample records for phragmites australis growing

  1. Characterization of the microbial community in the rhizosphere of Phragmites australis (cav.) trin ex. steudel growing in the Sun Island Wetland.

    PubMed

    Ma, Fang; Wu, Jieting; Wang, Li; Yang, Jixian; Li, Shiyang; Li, Zhe; Zhag, Xue

    2014-03-01

    Rhizospheric microorganisms are important for environmental conservancy. The constancy and variability of the microorganisms in the rhizosphere of Phragmites australis in relation to the spatiotemporal variations in wetland ecosystems were studied. During the peak and trough of the vegetative period of the Phragmites australis growing across the hydrologic gradients of the Sun Island Wetland, Biolog and denaturing gradient gel electrophoresis (DGGE) were used to investigate the rhizospheric microbial characteristics. Both methods demonstrated that the microbial activity, richness, and diversity decreased from summer to autumn. However, these properties did not show significant correlation with hydrologic gradient, except that the genetic richness and diversity of the fungi decreased with it. Cluster analysis also demonstrated that the rhizospheric microbial community seemed to be largely affected by a vegetative period. In addition, this research was extended to a broader range of determining the universal microorganisms, which showed notable adaptability.

  2. Environmental perspectives of Phragmites australis (Cav.) Trin. Ex. Steudel

    NASA Astrophysics Data System (ADS)

    Srivastava, Jatin; Kalra, Swinder J. S.; Naraian, Ram

    2014-09-01

    Extensive research is being conducted worldwide to find alternative and efficient systems to lessen the impacts of climate change and reduce environmental pollution. The genus Phragmites has proven ability to mitigate the environmental pollution of its surroundings. Common reed ( Phragmites australis (Cav.) Trin. Ex. Steudel), a graminaceous plant of cosmopolitan nature, has been extensively studied especially for the mitigation of environmental contamination. The capability of common reed to grow well at extreme environmental conditions such as elevated CO2 and high temperature is conferred by several factors such as change of carbon trapping mechanism (from C3 to C4 and vice versa), microbial association and biochemical adaptations. P. australis has been a most preferred unique plant system, especially in ecological engineering for improving the quality of wastewater. This paper reviews the current state of knowledge regarding the suitability of Phragmites australis for environmental remediation and summarizes recent advancements in our understanding of this grass.

  3. Effects of vegetative-periodic-induced rhizosphere variation on the uptake and translocation of metals in Phragmites australis (Cav.) Trin ex. Steudel growing in the Sun Island Wetland.

    PubMed

    Wu, Jieting; Wang, Li; Ma, Fang; Yang, Jixian; Li, Shiyang; Li, Zhe

    2013-05-01

    To evaluate the vegetative periodic effect of rhizosphere on the patterns of metal bioaccumulation, the concentrations of Mg, K, Ca, Mn, Zn, Fe, Cu, Cr, Ni, Cd and Pb in the corresponding rhizosphere soil and tissues of Phragmites australis growing in the Sun Island wetland (Harbin, China) were compared. The concentrations of Zn, Fe, Cu, Cr, Ni, Cd and Pb in roots were higher than in shoots, suggesting that roots are the primary accumulation organs for these metals and there exists an exclusion strategy for metal tolerance. In contrast, the rest of the metals showed an opposite trend, suggesting that they were not restricted in roots. Harvesting would particularly be an effective method to remove Mn from the environment. The concentrations of metals in shoots were generally higher in autumn than in summer, suggesting that Ph. australis possesses an efficient root-to-shoot translocation system, which is activated at the end of the growing season and allows more metals into the senescent tissues. Furthermore, metal bioaccumulation of Ph. australis was affected by vegetative periodic variation through the changing of physicochemical and microbial conditions. The rhizospheric microbial characteristics were significantly related to the concentrations of Mg, K, Zn, Fe and Cu, suggesting that microbial influence on metal accumulation is specific and selective, not eurytopic.

  4. Response of Arbuscular Mycorrhizal Fungi to Hydrologic Gradients in the Rhizosphere of Phragmites australis (Cav.) Trin ex. Steudel Growing in the Sun Island Wetland.

    PubMed

    Wang, Li; Wu, Jieting; Ma, Fang; Yang, Jixian; Li, Shiyang; Li, Zhe; Zhang, Xue

    2015-01-01

    Within the rhizosphere, AM fungi are a sensitive variable to changes of botanic and environmental conditions, and they may interact with the biomass of plant and other microbes. During the vegetative period of the Phragmites australis growing in the Sun Island Wetland (SIW), the variations of AM fungi colonization were studied. Root samples of three hydrologic gradients generally showed AM fungi colonization, suggesting that AM fungi have the ability for adaptation to flooded habitats. There were direct and indirect hydrological related effects with respect to AM fungi biomass, which interacted simultaneously in the rhizosphere. Though water content in soil and reed growth parameters were both positively associated with AM fungi colonization, only the positive correlations between reed biomass parameters and the colonization could be expected, or both the host plant biomass and the AM fungi could be beneficial. The variations in response of host plant to the edaphic and hydrologic conditions may influence the effectiveness of the plant-mycorrhizal association. This study included a hydrologic component to better assess the role and distribution of AM fungi in wetland ecosystems. And because of that, the range of AM fungi was extended, since they actually showed a notable adaptability to hydrologic gradients.

  5. Response of Arbuscular Mycorrhizal Fungi to Hydrologic Gradients in the Rhizosphere of Phragmites australis (Cav.) Trin ex. Steudel Growing in the Sun Island Wetland

    PubMed Central

    Wang, Li; Wu, Jieting; Ma, Fang; Yang, Jixian; Li, Shiyang; Li, Zhe; Zhang, Xue

    2015-01-01

    Within the rhizosphere, AM fungi are a sensitive variable to changes of botanic and environmental conditions, and they may interact with the biomass of plant and other microbes. During the vegetative period of the Phragmites australis growing in the Sun Island Wetland (SIW), the variations of AM fungi colonization were studied. Root samples of three hydrologic gradients generally showed AM fungi colonization, suggesting that AM fungi have the ability for adaptation to flooded habitats. There were direct and indirect hydrological related effects with respect to AM fungi biomass, which interacted simultaneously in the rhizosphere. Though water content in soil and reed growth parameters were both positively associated with AM fungi colonization, only the positive correlations between reed biomass parameters and the colonization could be expected, or both the host plant biomass and the AM fungi could be beneficial. The variations in response of host plant to the edaphic and hydrologic conditions may influence the effectiveness of the plant-mycorrhizal association. This study included a hydrologic component to better assess the role and distribution of AM fungi in wetland ecosystems. And because of that, the range of AM fungi was extended, since they actually showed a notable adaptability to hydrologic gradients. PMID:26146633

  6. Phragmites australis expansion in a restored brackish marsh: documentation at different time scales

    USGS Publications Warehouse

    Howard, Rebecca J.; Turluck, Theodore D.

    2013-01-01

    Invasive plants in restored habitats can alter the system such that restoration goals are not met. Non-native lineages of Phragmites australis (hereafter Phragmites) are invasive in North American wetlands, and their presence can be problematic because of decreased species diversity and altered physicochemical processes. Phragmites is a challenging species for restoration because both native and non-native lineages can co-occur. We documented Phragmites expansion in a brackish marsh in Louisiana, USA that was restored with dredged sediments. Invasive Phragmites clones were inadvertently planted at the site. Phragmites expansion was documented through field measurements and aerial imagery. No growth differences were apparent between lineages during the first growing season. Horizontal expansion of 2.27 ± 0.15 m (mean ± 1SE) 5 months after planting occurred through rhizome growth. Seven years after planting, three patches with a combined aerial cover of about 0.7 ha were delineated. The study verified that Phragmites can grow relatively rapidly and persist on dredged sediments. Long-term rapid growth of invasive Phragmites may be a positive attribute in areas subject to high erosion and subsidence rates, despite reductions in species diversity. Acceptability of the presence of invasive Phragmites will depend on restoration goals.

  7. Preface: Phragmites australis: A sheep in wolf's clothing?

    USGS Publications Warehouse

    Weinstein, M.P.; Keough, J.R.; Guntenspergen, G.R.; Litvin, S.Y.

    2003-01-01

    A. problem with national priorities for control or prevention of aquatic nuisance species is that we often do not know the full extent of the problem, if there is one. To address this issue, we hosted a technical forum and workshop-Phragmites australis: A Sheep in Wolf's Clothing?--with a focus on new research and critical reviews that address the role of Phragmites as a noxious weed. ... The Workshop helped focus the national effort in new multidisciplinary research to better understand the ecology of P australis and its ecosystem-level effects on the structure and function of coastal wetlands.

  8. Tracking Phragmites Australis Expansion in Bear River Migratory Bird Refuge using AggieAir Aircraft Data

    NASA Astrophysics Data System (ADS)

    Zaman, B.; McKee, M.

    2010-12-01

    This research examines the use of unmanned air vehicles (UAV), a cutting edge technology developed at the Utah Water research lab for acquiring airborne imagery using drones for the assessment of abundance of an invasive species Phragmites australis in a wetland vegetation setup. These UAV’s acquire multispectral data in the visible and near-infrared bands with a spatial resolution of 0.5 meters. The study area is the Bear River Migratory Bird Refuge (MBR) which lies in northern Utah, where the Bear River flows into the northeast arm of the Great Salt Lake. The Refuge protects the marshes found at the mouth of the Bear River; these marshes are the largest freshwater component of the Great Salt Lake ecosystem. A common reed, Phragmites australis, is a tall (1.5-4.0 m) coarse perennial grass found primarily in brackish and freshwater wetlands, growing at or above mean high water. The methodology is to build Bayesian statistical supervised classification model using relevance vector machine (RVM) employing the inexpensive and readily available UAV data. The UAV images of the bird refuge are processed to obtain calibrated reflectance imagery. Thereafter, the isodata clustering algorithm is applied to classify the multispectral imagery into different classes. Using ground sampling of the species, pixels containing the Phragmites australis are deduced. The training set for the supervised RVM classification model is prepared using the deduced pixel values. A separate set of ground sampling points containing the Phragmites australis are kept aside for validation. The distribution of Phragmites australis in the study area as obtained from RVM classification model is compared to the validation set. The RVM model results for tracking of Phragmites are encouraging and the new technique has promising real-time implementation for similar applications.

  9. Metabolism of ibuprofen by Phragmites australis: uptake and phytodegradation.

    PubMed

    He, Yujie; Langenhoff, Alette A M; Sutton, Nora B; Rijnaarts, Huub H M; Blokland, Marco H; Chen, Feiran; Huber, Christian; Schröder, Peter

    2017-03-27

    This study explores ibuprofen (IBP) uptake and transformation in the wetland plant species Phragmites australis and the underlying mechanisms. We grew P. australis in perlite under greenhouse conditions and treated plants with 60 µg/l of IBP. Roots and rhizomes (RR), stems and leaves (SL), and liquid samples were collected during 21 days of exposure. Results show that P. australis can take up, translocate, and degrade IBP. IBP was completely removed from the liquid medium after 21 days with a half-life of 2.1 days. IBP accumulated in RR and was partly translocated to SL. Meanwhile, four intermediates were detected in the plant tissues: hydroxy-IBP, 1,2-dihydroxy-IBP, carboxy-IBP and glucopyranosyloxy-hydroxy-IBP. Cytochrome P450 monooxygenase was involved in the production of the two hydroxy intermediates. We hypothesize that transformation of IBP was first catalyzed by P450, and then by glycosyltransferase, followed by further storage or metabolism in vacuoles or cell walls. No significant phytotoxicity was observed based on relative growth of plants and stress enzyme activities. In conclusion, we demonstrated for the first time that P. australis degrades IBP from water and is therefore a suitable species for application in constructed wetlands to clean wastewater effluents containing IBP and possibly also other micropollutants.

  10. [A Contrastive Study on Salt-alkaline Resistance and Removal Efficiency of Nitrogen and Phosphorus by Phragmites australis and Typha angustifolia in Coastal Estuary Area].

    PubMed

    Chen, You-yuan; Sun, Ping; Chen, Guang-lin; Wang, Ning-ning

    2015-04-01

    The salt and alkali contents were so high that the ecological landscape was depressed in water body of a coastal estuary area. Screening some plants which could not only tolerate saline-alkaline but also effectively remove nitrogen and phosphorus was therefore in urgent need. The tolerance range and removal rate of nitrogen and phosphorus by Phragmites australis and Typha angustifolia under salt and pH stress were investigated by hydroponic experiments. The results showed that Phragmites australis could tolerate at least 10 per thousand salinity and pH 8.5, while Typha angustifolia tolerated 7.5 per thousand salinity and pH 8.0. Combined with the change of the growth and physiological indexes (relative conductivity, proline, chlorophyll and root activity), the salt resistance of Phragmites australis was stronger than that of Typha angustifolia. Under salt stress, the removal rate of ammonia nitrogen of Phragmites australis was higher. The removal rates of nitrate nitrogen and phosphorus of Typha angustifolia were 2.5% and 7.3% higher than those of Phragmites australis in average, respectively, because of the high biomass of Typha angustifolias. The total nitrogen removal rate was equivalent. Under pH stress, the removal rate of ammonia nitrogen and total phosphorus of Phragmites australis was a little higher than that of Typha angustifolia. However, Typha angustifolia had a higher removal rate of total nitrogen, which was 8.2% higher than that of Phragmites australis. All the analysis showed that both Phragmites australis and Typha angustifolia could be used as alternative plants to grow and remove nitrogen and phosphorus in the high salt-alkaline water body in coastal estuary area.

  11. Antioxidant response of Phragmites australis to Cu and Cd contamination.

    PubMed

    Rocha, A Cristina S; Almeida, C Marisa R; Basto, M Clara P; Vasconcelos, M Teresa S D

    2014-11-01

    Metals are known to induce oxidative stress in plant cells. Antioxidant thiolic compounds are known to play an important role in plants׳ defence mechanisms against metal toxicity but, regarding salt marsh plants, their role is still very poorly understood. In this work, the involvement of non-protein thiols (NPT), such as cysteine (Cys), reduced glutathione (GSH), oxidised glutathione (GSSG) and total acid-soluble SH compounds (total thiols), in the tolerance mechanisms of the marsh plant Phragmites australis against Cu and Cd toxicity was assessed. Specimens of this plant, freshly harvested in an estuarine salt marsh, were exposed, for 7 days, to rhizosediment soaked with the respective elutriate contaminated with Cu (0, 10 and 100 mg/L) or Cd (0, 1, 10 mg/L). In terms of NPT production, Cu and Cd contamination induced different responses in P. australis. The content of Cys increased in plant tissue after plant exposure to Cu, whereas Cd contamination led to a decrease in GSSG levels. In general, metal contamination did not cause a significant variation on GSH levels. Both metals influenced, to some extent, the production of other thiolic compounds. Despite the accumulation of considerable amounts of Cu and Cd in belowground tissues, no visible toxicity signs were observed. So, antioxidant thiolic compounds were probably involved in the mechanisms used by P. australis to alleviate metal toxicity. As P. australis is considered suitable for phytostabilising metal-contaminated sediments, understanding its tolerance mechanisms to toxic metals is important to optimise the conditions for applying this plant in phytoremediation procedures.

  12. Energy and water balance response of a vegetated wetland to herbicide treatment of invasive Phragmites australis

    NASA Astrophysics Data System (ADS)

    Mykleby, Phillip M.; Lenters, John D.; Cutrell, Gregory J.; Herrman, Kyle S.; Istanbulluoglu, Erkan; Scott, Durelle T.; Twine, Tracy E.; Kucharik, Christopher J.; Awada, Tala; Soylu, Mehmet E.; Dong, Bo

    2016-08-01

    The energy and water balance of a Phragmites australis dominated wetland in south central Nebraska was analyzed to assess consumptive water use and the potential for "water savings" as a result of vegetation eradication via herbicide treatment. Energy balance measurements were made at the field site for two growing seasons (treated and untreated), including observations of net radiation, heat storage, and sensible heat flux, which was measured using a large-aperture scintillometer. Latent heat flux was calculated as a residual of the energy balance, and comparisons were made between the two growing seasons and with model simulations to examine the relative impacts of vegetation removal and climate variability. Observed ET rates dropped by roughly 32% between the two growing seasons, from a mean of 4.4 ± 0.7 mm day-1 in 2009 (with live vegetation) to 3.0 ± 0.8 mm day-1 in 2010 (with dead P. australis). These results are corroborated by the Agro-IBIS model simulations, and the reduction in ET implies a total "water savings" of 245 mm over the course of the growing season. The significant decreases in ET were accompanied by a more-than-doubling of sensible heat flux, as well as a ∼60% increase in heat storage due to decreased LAI. Removal of P. australis was also found to cause measurable changes in the local micrometeorology at the wetland. Consistent with the observed increase in sensible heat flux during 2010, warmer, drier, windier conditions were observed in the dead, P. australis section of the wetland, compared to an undisturbed section of live, native vegetation. Modeling results suggest that the elimination of transpiration in 2010 was partially offset by an increase in surface evaporation, thereby reducing the subsequent water savings by roughly 60%. Thus, the impact of vegetation removal depends on the local climate, depth to groundwater, and management decisions related to regrowth of vegetation.

  13. Role of Phragmites australis (common reed) for heavy metals phytoremediation of estuarine sediments.

    PubMed

    Cicero-Fernández, Diego; Peña-Fernández, Manuel; Expósito-Camargo, Jose A; Antizar-Ladislao, Blanca

    2016-01-01

    The ability of Phragmites australis to take up heavy metals (Co, Ni, Mo, Cd, Pb, Cr, Cu, Fe, Mn, Zn, and Hg) and other trace elements (As, Se, Ba), from estuarine sediments was investigated using a pilot plant experimental approach. Bioaccumulation (BCF) and translocation factors (TF) were calculated in vegetative and senescence periods for two populations of P. australis, from contaminated (MIC) and non-contaminated (GAL) estuarine sediments, respectively, both growing in estuarine contaminated sediment (RIA) from ría del Carmen y Boo, Santander Bay, Spain. The highest BCF values were obtained for Ni (0.43), Ba (0.43) Mo (0.36), Cr (0.35), and Cd (0.31) for plants collected from site GAL following the senescence period. The highest BCF values recorded for plants collected from MIC following the senescence period were for Mo (0.22) and Cu (0.22). Following senescence, plants collected from GAL and MIC presented TF>1 for Ni, Mo, Se, and Zn, and in addition plants collected from MIC presented TF>1 for Ba, Cr, and Mn. A substantial increase of Micedo's rhizosphere, six times higher than Galizano's rhizosphere, suggested adaptation to contaminated sediment. The evaluated communities of P. australis demonstrated their suitability for phytoremediation of heavy metals contaminated estuarine sediments.

  14. Palatability and chemical defense of Phragmites australis to the marsh periwinkle snail Littoraria irrorata.

    PubMed

    Hendricks, Lindsey G; Mossop, Hannah E; Kicklighter, Cynthia E

    2011-08-01

    Coastal marsh habitats are impacted by many disturbances, including habitat destruction, pollution, and the introduction of invasive species. The common reed, Phragmites australis, has been particularly invasive in the mesohaline regions of the Chesapeake Bay, but few studies have investigated its role in trophic interactions with North American marsh consumers. The marsh periwinkle snail Littoraria irrorata is a common grazer in marshes and grazes on the native grass Spartina alterniflora. Whether this snail grazes on Phragmites has not been addressed. We found Spartina leaves to be tougher than those of Phragmites, but despite this, snails consumed significantly more Spartina than Phragmites. Subsequent experiments demonstrated that Phragmites is chemically deterrent to snails by an unknown, moderately polar, compound. Further studies are required to more fully understand the interactions between Phragmites, herbivores, and Spartina, and how they may impact marsh ecosystems.

  15. Differences in the removal mechanisms of Undaria pinnatifida and Phragmites australis as biomaterials for lead removal.

    PubMed

    Soto-Rios, Paula Cecilia; Nakano, Kazunori; Leon-Romero, Marco; Aikawa, Yoshio; Arai, Shigeyuki; Nishimura, Osamu

    2015-01-01

    This study offers the opportunity to utilize Undaria pinnatifida and Phragmites australis to remove lead from water in permeable reactive barrier (PRB) technology. Its efficacy was tested using batch experiments and PRB column systems. From the batch experiment results, a higher adsorption capacity was observed for Undaria pinnatifida. Nevertheless, Phragmites australis in the column system efficiently removed lead and the breakthrough occurred at the same time for both biomaterials. To dissipate this difference, a sequential extraction for metal speciation analysis was used for both columns. The results have shown that each biomaterial has a dominant mechanism. Phragmites australis removed lead by physical adsorption, whereas Undaria pinnatifida showed a higher tendency to bind lead due to organic matter, primary and secondary minerals.

  16. Accumulation of Metals and Boron in Phragmites australis Planted in Constructed Wetlands Polishing Real Electroplating Wastewater.

    PubMed

    Sochacki, Adam; Guy, Bernard; Faure, Olivier; Surmacz-Górska, Joanna

    2015-01-01

    The concentration of metals (Al, Cu, Fe, Mn, Ni, Zn) and B were determined in the above- and belowground biomass of Phragmites australis collected from the microcosm constructed wetland system used for the polishing of real electroplating wastewater. Translocation factor and bioconcentration factor were determined. Pearson correlation test was used to determine correlation between metal concentration in substrate and above- and belowground parts of Phragmites australis. The obtained results suggested that Phragmites australis did not play a major role as an accumulator of metals. It was observed also that the substrate could have exerted an effect on the translocation of Ni, Cu, Zn and Mn. The analysed concentrations of metals and B in biomass were in the range or even below the concentrations reported in the literature with the exception of Ni. The aboveground biomass was found suitable as a composting input in terms of metals concentrations.

  17. The potential for constructed wetlands to treat alkaline bauxite-residue leachate: Phragmites australis growth.

    PubMed

    Higgins, D; Curtin, T; Pawlett, M; Courtney, R

    2016-12-01

    High alkalinity (pH > 12) of bauxite-residue leachates presents challenges for the long-term storage and managements of the residue. Recent evidence has highlighted the potential for constructed wetlands to effectively buffer the alkalinity, but there is limited evidence on the potential for wetland plants to establish and grow in soils inundated with residue leachate. A pot-based trial was conducted to investigate the potential for Phragmites australis to establish and grow in substrate treated with residue leachate over a pH range of 8.6-11.1. The trial ran for 3 months, after which plant growth and biomass were determined. Concentrations of soluble and exchangeable trace elements in the soil substrate and also in the aboveground and belowground biomass were determined. Residue leachate pH did not affect plant biomass or microbial biomass. With the exception of Na, there was no effect on exchangeable trace elements in the substrate; however, increases in soluble metals (As, Cd and Na) were observed with increasing leachate concentration. Furthermore, increases in Al, As and V were observed in belowground biomass and for Cd and Cr in aboveground biomass. Concentrations within the vegetation biomass were less than critical phytotoxic levels. Results demonstrate the ability for P. australis to grow in bauxite-residue leachate-inundated growth media without adverse effects.

  18. Effect of cellulose wastes upon the growth of Phragmites australis.

    PubMed

    Jordan, M; Wilken, D; Gerth, A; Muñoz, O

    2008-01-01

    Growth responses of Phragmites australis (Cav.) Trin. Ex Steud, (reed grass), a helophyte species, were examined under in vitro and greenhouse conditions in the presence of various residues from a Kraft pulp mill. Plant tolerance to solid residues (ashes, dregs, flyashes, grits, primary sludge, and brown stock rejects) was tested in vitro. Solid residues were added separately up to 30% (w/v), as well a liquid residue up to 30% (v/v), to a Murashige and Skoog (1962) sucrose-free nutrient media with (5 mg l(-1)) 6-benzylaminopurine. After 2 mo in vitro, plantlets developed well in the presence of up to 10% solid or liquid wastes, but higher concentrations of either limited growth. This effect was mainly attributed to the plant's uptake and accumulation of various elements such as sodium, iron, copper, manganese, and boron, which are common to these waste types, thus showing an efficient phytoremediation potential. When added to MS media, the concentration of these elements generally decreased in the residual media after 2 mo of culture: the initial sodium, iron, and copper content in the growth media was reduced ca. 10-fold detected; a 5-fold reduction occurred for manganese and boron. In experiments under greenhouse conditions with in vitro propagated plantlets potted in mixtures of a commercial organic soil and residues, significant differences in plant development (plant size and fresh weight increase) were observed in the presence of ashes mixed at levels of 20% and 30%, compared to the control in organic soil. For other solid wastes, plant growth was inhibited as the concentration of each waste increased, causing chlorosis and/or plant necrosis.

  19. Flavobacterium phragmitis sp. nov., an endophyte of reed (Phragmites australis).

    PubMed

    Liu, Min; Li, Yan Hong; Liu, Yang; Zhu, Jing Nan; Liu, Qun Fang; Liu, Yin; Gu, Jin Gang; Zhang, Xiao Xia; Li, Chun Li

    2011-11-01

    A Gram-staining-negative bacterium, designated strain BLN2(T), was isolated from within the roots of reeds (Phragmites australis) in Beijing Cuihu Wetland (China) and characterized using a polyphasic taxonomic approach. The cells were yellow-pigmented, rod-shaped, strictly aerobic and devoid of flagella, but showed gliding motility. Strain BLN2(T) produced yellow, translucent, circular and convex colonies, with optimal growth at 30 °C and pH 7.0. The major respiratory quinone was menaquinone 6 (MK-6) and the predominant fatty acids were iso-C(15 : 0), summed feature 3 (comprising C(16 : 1)ω7c and/or C(16 : 1)ω6c), C(16 : 0) 3-OH, C(16 : 0,) iso-C(17 : 0) 3-OH and iso-C(15 : 0) 3-OH. The G+C content of the genomic DNA was 34.8 mol%. The 16S rRNA gene sequence analysis showed that strain BLN2(T) belonged to the genus Flavobacterium and was most closely related to Flavobacterium anhuiense CGMCC 1.6859(T) (97.0 % sequence similarity). The DNA-DNA relatedness between strain BLN2(T) and F. anhuiense CGMCC 1.6859(T) was 25.7 %. Based on the phenotypic data and phylogenetic inference presented, it is concluded that strain BLN2(T) represents a novel species within the genus Flavobacterium, for which the name Flavobacterium phragmitis sp. nov. is proposed. The type strain is BLN2(T) ( = DSM 23314(T) = CGMCC 1.10370(T)).

  20. Collaborations, research, and adaptive management to address nonnative Phragmites australis in the Great Lakes Basin

    USGS Publications Warehouse

    Kowalski, Kurt P.

    2016-06-30

    Phragmites australis, also known as common reed, is a native North American wetland grass that has grown in North America for thousands of years. More recently, a nonnative, invasive variety of Phragmites from Eurasia is rapidly invading wetlands across the continental United States and other parts of North America, where it negatively impacts humans and the environment. U.S. Geological Survey scientists, funded by the Great Lakes Restoration Initiative, are leading innovative efforts to improve management of nonnative Phragmites in the Great Lakes Basin.

  1. Ailanthus Altissima and Phragmites Australis for chromium removal from a contaminated soil.

    PubMed

    Ranieri, Ezio; Fratino, Umberto; Petrella, Andrea; Torretta, Vincenzo; Rada, Elena Cristina

    2016-08-01

    The comparative effectiveness for hexavalent chromium removal from irrigation water, using two selected plant species (Phragmites australis and Ailanthus altissima) planted in soil contaminated with hexavalent chromium, has been studied in the present work. Total chromium removal from water was ranging from 55 % (Phragmites) to 61 % (Ailanthus). After 360 days, the contaminated soil dropped from 70 (initial) to 36 and 41 mg Cr/kg (dry soil), for Phragmites and Ailanthus, respectively. Phragmites accumulated the highest amount of chromium in the roots (1910 mg Cr/kg(dry tissue)), compared with 358 mg Cr/kg(dry tissue) for Ailanthus roots. Most of chromium was found in trivalent form in all plant tissues. Ailanthus had the lowest affinity for Cr(VI) reduction in the root tissues. Phragmites indicated the highest chromium translocation potential, from roots to stems. Both plant species showed good potentialities to be used in phytoremediation installations for chromium removal.

  2. Uptake of carbamazepine by rhizomes and endophytic bacteria of Phragmites australis.

    PubMed

    Sauvêtre, Andrés; Schröder, Peter

    2015-01-01

    Carbamazepine is an antiepileptic and mood-stabilizing drug which is used widely in Europe and North America. In the environment, it is found as a persistent and recalcitrant contaminant, being one of the most prominent hazardous pharmaceuticals and personal care products in effluents of wastewater treatment plants. Phragmites australis is one of the species with both, the highest potential of detoxification and phytoremediation. It has been used successfully in the treatment of industrial and municipal wastewater. Recently, the identification of endophytic microorganisms from different plant species growing in contaminated sites has provided a list of candidates which could be used as bio-inoculants for bioremediation of difficult compounds. In this study, Phragmites australis plants were exposed to 5 mg/L of carbamazepine. After 9 days the plants had removed 90% of the initial concentration. Endophytic bacteria were isolated from these plants and further characterized. Phylogenetic analysis based on 16S rDNA sequencing revealed that the majority of these isolates belong to three groups: Proteobacteria, Actinobacteria, and Bacteroidetes. Carbamazepine uptake and plant growth promoting (PGP) traits were analyzed among the isolates. Ninety percent of the isolates produce indole acetic acid (IAA) and all of them possess at least one of the PGP traits tested. One isolate identified as Chryseobacterium taeanense combines good carbamazepine uptake and all of the PGP traits. Rhizobium daejeonense can remove carbamazepine and produces 23 μg/mL of IAA. Diaphorobacter nitroreducens and Achromobacter mucicolens are suitable for carbamazepine removal while both, Pseudomonas veronii and Pseudomonas lini show high siderophore production and phosphate solubilization. Alone or in combination, these isolates might be applied as inoculates in constructed wetlands in order to enhance the phytoremediation of carbamazepine during wastewater treatment.

  3. Uptake of carbamazepine by rhizomes and endophytic bacteria of Phragmites australis

    PubMed Central

    Sauvêtre, Andrés; Schröder, Peter

    2015-01-01

    Carbamazepine is an antiepileptic and mood-stabilizing drug which is used widely in Europe and North America. In the environment, it is found as a persistent and recalcitrant contaminant, being one of the most prominent hazardous pharmaceuticals and personal care products in effluents of wastewater treatment plants. Phragmites australis is one of the species with both, the highest potential of detoxification and phytoremediation. It has been used successfully in the treatment of industrial and municipal wastewater. Recently, the identification of endophytic microorganisms from different plant species growing in contaminated sites has provided a list of candidates which could be used as bio-inoculants for bioremediation of difficult compounds. In this study, Phragmites australis plants were exposed to 5 mg/L of carbamazepine. After 9 days the plants had removed 90% of the initial concentration. Endophytic bacteria were isolated from these plants and further characterized. Phylogenetic analysis based on 16S rDNA sequencing revealed that the majority of these isolates belong to three groups: Proteobacteria, Actinobacteria, and Bacteroidetes. Carbamazepine uptake and plant growth promoting (PGP) traits were analyzed among the isolates. Ninety percent of the isolates produce indole acetic acid (IAA) and all of them possess at least one of the PGP traits tested. One isolate identified as Chryseobacterium taeanense combines good carbamazepine uptake and all of the PGP traits. Rhizobium daejeonense can remove carbamazepine and produces 23 μg/mL of IAA. Diaphorobacter nitroreducens and Achromobacter mucicolens are suitable for carbamazepine removal while both, Pseudomonas veronii and Pseudomonas lini show high siderophore production and phosphate solubilization. Alone or in combination, these isolates might be applied as inoculates in constructed wetlands in order to enhance the phytoremediation of carbamazepine during wastewater treatment. PMID:25750647

  4. Hydroponic uptake and distribution of nitrobenzene in Phragmites australis: potential for phytoremediation.

    PubMed

    Song, Yanyu; Song, Changchun; Ju, Songbai; Chai, Junhai; Guo, Jun; Zhao, Quandong

    2010-03-01

    Phragmites australis was grown hydroponically in nutrient solutions containing nitrobenzene to examine the potential for treatment of contaminated waters through phytoremediation. The hydroponic solutions and plant tissue were sampled each day during the five day growth period and tested for nitrobenzene. Plant tissue analysis included both rhizome and shoot sections of the plant. The average half lives and disappearance rate of nitrobenzene in the nutrient solution was 1.85 days and 88.10%, respectively. The levels of nitrobenzene in rhizomes and shoots of Phragmites australis increased with higher exogenous concentrations. For the highest treatment, nitrobenzene measurements in the rhizome tissue were much higher than the plant shoots until the third day. Shoot sections initially showed elevated concentrations and then decreased. This variation is presumably due to the translocation of the target compound from the rhizomes to shoots. Our findings indicate that Phragmites australis removed nitrobenzene from the hydroponic solutions and accumulated the compound within the plant tissue. This activity makes Phragmites australis a good candidate species for the phytoremediation of nitrobenzene contaminated waters.

  5. Effect of Salinity on Common Reed (Phragmites australis) in a Restored Salt Marsh in Rhode Island

    EPA Science Inventory

    Tidal wetlands have undergone extensive degradation throughout the years because of interference with tidal flow from construction, dredging, and invasion of non-native plants such Phragmites australis. In 1956, a 4-lane highway was constructed in Galilee, Rhode Island, USA, cro...

  6. Release of Metals by the Leaves of the Salt Marsh Grasses Spartina alterniflora and Phragmites australis

    NASA Astrophysics Data System (ADS)

    Burke, D. J.; Weis, J. S.; Weis, P.

    2000-08-01

    The perennial grass Spartina alterniflora, common to salt marshes of eastern North America, is known to accumulate metals from marsh sediment and release them into the environment. One pathway by which Spartina alterniflora releases metals is through the excretion of metal-containing salts produced by leaf salt glands. We examined the differential release of metals by Spartina alterniflora and the invasive perennial grass Phragmites australis in an urban marsh ecosystem. Leaching rates were measured by cleaning residues off leaf surfaces under field and controlled laboratory conditions. Leaf residues and leaf tissue were analysed for copper, chromium, lead and zinc by atomic absorption spectrophotometry. Spartina alterniflora was found to release significantly more metal through leaf tissue than Phragmites australis, under both field and laboratory situations. Spartina alterniflora was also found to accumulate significantly more chromium and lead in leaves than Phragmites australis. Therefore, Spartina alterniflora can release larger quantities of metals into the marsh environment than Phragmites australis, through both excretion and leaf deposition.

  7. Salt tolerance and osmotic adjustment of Spartina alterniflora (Poaceae) and the invasive M haplotype of Phragmites australis (Poaceae) along a salinity gradient.

    PubMed

    Vasquez, Edward A; Glenn, Edward P; Guntenspergen, Glenn R; Brown, J Jed; Nelson, Stephen G

    2006-12-01

    An invasive variety of Phragmites australis (Poaceae, common reed), the M haplotype, has been implicated in the spread of this species into North American salt marshes that are normally dominated by the salt marsh grass Spartina alterniflora (Poaceae, smooth cordgrass). In some European marshes, on the other hand, Spartina spp. derived from S. alterniflora have spread into brackish P. australis marshes. In both cases, the non-native grass is thought to degrade the habitat value of the marsh for wildlife, and it is important to understand the physiological processes that lead to these species replacements. We compared the growth, salt tolerance, and osmotic adjustment of M haplotype P. australis and S. alterniflora along a salinity gradient in greenhouse experiments. Spartina alterniflora produced new biomass up to 0.6 M NaCl, whereas P. australis did not grow well above 0.2 M NaCl. The greater salt tolerance of S. alterniflora compared with P. australis was due to its ability to use Na(+) for osmotic adjustment in the shoots. On the other hand, at low salinities P. australis produced more shoots per gram of rhizome tissue than did S. alterniflora. This study illustrates how ecophysiological differences can shift the competitive advantage from one species to another along a stress gradient. Phragmites australis is spreading into North American coastal marshes that are experiencing reduced salinities, while Spartina spp. are spreading into northern European brackish marshes that are experiencing increased salinities as land use patterns change on the two continents.

  8. Salt tolerance and osmotic adjustment of Spartina alterniflora (Poaceae) and the invasive M haplotype of Phragmites australis (Poaceae) along a salinity gradient

    USGS Publications Warehouse

    Vasquez, Edward A.; Glenn, Edward P.; Guntenspergen, Glenn R.; Brown, J. Jed; Nelson, Stephen G.

    2006-01-01

    An invasive variety of Phragmites australis (Poaceae, common reed), the M haplotype, has been implicated in the spread of this species into North American salt marshes that are normally dominated by the salt marsh grass Spartina alterniflora (Poaceae, smooth cordgrass). In some European marshes, on the other hand, Spartina spp. derived from S. alterniflora have spread into brackish P. australis marshes. In both cases, the non-native grass is thought to degrade the habitat value of the marsh for wildlife, and it is important to understand the physiological processes that lead to these species replacements. We compared the growth, salt tolerance, and osmotic adjustment of M haplotype P. australis and S. alterniflora along a salinity gradient in greenhouse experiments. Spartina alterniflora produced new biomass up to 0.6 M NaCl, whereas P. australis did not grow well above 0.2 M NaCl. The greater salt tolerance of S. alterniflora compared with P. australis was due to its ability to use Na+ for osmotic adjustment in the shoots. On the other hand, at low salinities P. australis produced more shoots per gram of rhizome tissue than did S. alterniflora. This study illustrates how ecophysiological differences can shift the competitive advantage from one species to another along a stress gradient. Phragmites australis is spreading into North American coastal marshes that are experiencing reduced salinities, while Spartina spp. are spreading into northern European brackish marshes that are experiencing increased salinities as land use patterns change on the two continents.

  9. [Bud population dynamics of Phragmites australis in heterogeneous habitats of Northeast grassland, China].

    PubMed

    2015-02-01

    To adapt ecological environment, typical clonal plants can occur continuously by means of buds. The changes in the bud bank and bud flow in the heterogeneous habitats become the foundation for deep understanding the characteristics of vegetative propagation. By sampling soil from the unit area, a comparative analysis was performed for rhizome bud population dynamics of Phragmites australis community in both meadow soil and saline-alkali soil habitats in meadow grassland of Northeast China. The one-age class rhizome buds formed in the current year were used as input, with the other age classes rhizome buds as output, counting the dormancy buds and death buds. The results showed that the storage, input, output, dormancy, death and the input rates of P. australis rhizome bud populations in meadow soil habitat were significantly higher than that in saline-alkali habitat. There was no significant difference in output rate between the two habitats. The dormant rate in saline-alkali habitat was significantly greater than that in meadow soil habitat. The death rates remained at relatively low levels in both, less than 2%. With the going of growing season, the input buds and input rate of bud bank increased in the two habitats, while the output buds remained relatively stable. The output rate increased first and decreased later, the dormancy buds and dormant rate decreased. Bud bank and bud flow were positively related to soil moisture, soil organic matter and soil available nitrogen content. However, they were negatively related to soil pH value and soil available phosphorus content. Bud bank and bud flow had a similar seasonal variation. Constantly for both habitats, P. australis populations generated new rhizome buds supplied to the bud bank and kept a stable output to maintain their vegetative propagation.

  10. Phytoextraction of chloride from a cement kiln dust (CKD) contaminated landfill with Phragmites australis.

    PubMed

    McSorley, Kaitlin; Rutter, Allison; Cumming, Robert; Zeeb, Barbara A

    2016-05-01

    Cement kiln dust (CKD) is a globally produced by-product from cement manufacturing that is stockpiled or landfilled. Elevated concentrations of chloride pose toxic threats to plants and aquatic communities, as the anion is highly mobile in water and can leach into surrounding water sources. Re-vegetation and in situ phytoextraction of chloride from a CKD landfill in Bath, ON, Canada, was investigated with the resident invasive species Phragmites australis (haplotype M). Existing stands of P. australis were transplanted from the perimeter of the site into the highest areas of contamination (5.9×10(3)μg/g). Accumulation in the shoots of P. australis was quantified over one growing season by collecting samples from the site on a bi-weekly basis and analyzing for chloride. Concentrations decreased significantly from early May (24±2.2×10(3)μg/g) until mid-June (15±2.5×10(3)μg/g), and then remained stable from June to August. Shoot chloride accumulation was not significantly affected by water level fluctuations at the site, however elevated potassium concentrations in the soil may have contributed to uptake. Based on shoot chloride accumulation and total biomass, it was determined that phytoextraction from the CKD landfill can remove 65±4kg/km(2) of chloride per season. Based on this extraction rate, removal of chloride present in the highly contaminated top 10cm of soil can be achieved in 3-9years. This is the first study to apply phytotechnologies at a CKD landfill, and to successfully demonstrate in situ phytoextraction of chloride.

  11. Functional Role of Bacteria from Invasive Phragmites australis in Promotion of Host Growth.

    PubMed

    Soares, M A; Li, H-Y; Kowalski, K P; Bergen, M; Torres, M S; White, J F

    2016-08-01

    We hypothesize that bacterial endophytes may enhance the competitiveness and invasiveness of Phragmites australis. To evaluate this hypothesis, endophytic bacteria were isolated from P. australis. The majority of the shoot meristem isolates represent species from phyla Firmicutes, Proteobacteria, and Actinobacteria. We chose one species from each phylum to characterize further and to conduct growth promotion experiments in Phragmites. Bacteria tested include Bacillus amyloliquefaciens A9a, Achromobacter spanius B1, and Microbacterium oxydans B2. Isolates were characterized for known growth promotional traits, including indole acetic acid (IAA) production, secretion of hydrolytic enzymes, phosphate solubilization, and antibiosis activity. Potentially defensive antimicrobial lipopeptides were assayed for through application of co-culturing experiments and mass spectrometer analysis. B. amyloliquefaciens A9a and M. oxydans B2 produced IAA. B. amyloliquefaciens A9a secreted antifungal lipopeptides. Capability to promote growth of P. australis under low nitrogen conditions was evaluated in greenhouse experiments. All three isolates were found to increase the growth of P. australis under low soil nitrogen conditions and showed increased absorption of isotopic nitrogen into plants. This suggests that the Phragmites microbes we evaluated most likely promote growth of Phragmites by enhanced scavenging of nitrogenous compounds from the rhizosphere and transfer to host roots. Collectively, our results support the hypothesis that endophytic bacteria play a role in enhancing growth of P. australis in natural populations. Gaining a better understanding of the precise contributions and mechanisms of endophytes in enabling P. australis to develop high densities rapidly could lead to new symbiosis-based strategies for management and control of the host.

  12. Functional role of bacteria from invasive Phragmites australis in promotion of host growth

    USGS Publications Warehouse

    Soares, M. A.; Li, H-Y; Kowalski, Kurt P.; Bergen, M.; Torres, M. S.; White, J. F.

    2016-01-01

    We hypothesize that bacterial endophytes may enhance the competitiveness and invasiveness of Phragmites australis. To evaluate this hypothesis, endophytic bacteria were isolated from P. australis. The majority of the shoot meristem isolates represent species from phyla Firmicutes, Proteobacteria, and Actinobacteria. We chose one species from each phylum to characterize further and to conduct growth promotion experiments in Phragmites. Bacteria tested include Bacillus amyloliquefaciens A9a, Achromobacter spanius B1, and Microbacterium oxydans B2. Isolates were characterized for known growth promotional traits, including indole acetic acid (IAA) production, secretion of hydrolytic enzymes, phosphate solubilization, and antibiosis activity. Potentially defensive antimicrobial lipopeptides were assayed for through application of co-culturing experiments and mass spectrometer analysis. B. amyloliquefaciens A9a and M. oxydans B2 produced IAA. B. amyloliquefaciens A9a secreted antifungal lipopeptides. Capability to promote growth of P. australis under low nitrogen conditions was evaluated in greenhouse experiments. All three isolates were found to increase the growth of P. australis under low soil nitrogen conditions and showed increased absorption of isotopic nitrogen into plants. This suggests that the Phragmites microbes we evaluated most likely promote growth of Phragmites by enhanced scavenging of nitrogenous compounds from the rhizosphere and transfer to host roots. Collectively, our results support the hypothesis that endophytic bacteria play a role in enhancing growth of P. australis in natural populations. Gaining a better understanding of the precise contributions and mechanisms of endophytes in enabling P. australis to develop high densities rapidly could lead to new symbiosis-based strategies for management and control of the host.

  13. Sustainable biodegradation of phenolic endocrine-disrupting chemicals by Phragmites australis-rhizosphere bacteria association.

    PubMed

    Toyama, T; Ojima, T; Tanaka, Y; Mori, K; Morikawa, M

    2013-01-01

    The efficacy of two rhizobacteria (Sphingobium fuliginis TIK1 and Sphingobium sp. IT4) of Phragmites australis for the sustainable treatment of water polluted with phenolic endocrine-disrupting chemicals (EDCs) was investigated. Strains TIK1 and IT4 have recently been isolated from Phragmites rhizosphere and shown to degrade various 4-alkylphenols-TIK1 via phenolic ring hydroxylation and meta-cleavage and IT4 via ipso-hydroxylation. The two strains also degraded bisphenol A (BPA), bisphenol B, bisphenol E, bisphenol F, bisphenol P and bisphenol S (BPS). Thus, strains TIK1 and IT4 have wide degradation spectra for phenolic EDCs. The two strains utilized Phragmites root extracts as a sole carbon source and sustainably colonized Phragmites roots, where they degraded phenolic EDCs. In sequencing batch reactor experiments using Phragmites in association with TIK1 or IT4, both associations repeatedly removed phenolic EDCs from polluted secondary effluent water (BPA, BPS, 4-tert-butylphenol, 4-tert-octylphenol and 4-nonylphenol) from polluted secondary effluent water. The results suggest that hydroponic systems using Phragmites-TIK and Phragmites-IT4 associations would be useful for sustainable treatment of polluted waters containing various phenolic EDCs.

  14. Moving from a regional to a continental perspective of Phragmites australis invasion in North America

    PubMed Central

    Kettenring, Karin M.; de Blois, Sylvie; Hauber, Donald P.

    2012-01-01

    Aims We use a regional comparison of Phragmites australis (common reed) subsp. americanus, P. australis subsp. berlandieri and introduced P. australis (possibly five sublineages) in the Chesapeake Bay, the St Lawrence River, Utah and the Gulf Coast to inform a North American perspective on P. australis invasion patterns, drivers, impacts and research needs. Findings and research needs Our regional assessments reveal substantial diversity within and between the three main lineages of P. australis in terms of mode of reproduction and the types of environment occupied. For introduced P. australis, the timing of introduction also differed between the regions. Nevertheless, a common finding in these regions reinforces the notion that introduced P. australis is opportunistic and thrives in disturbed habitats. Thus, we expect to see substantial expansion of introduced P. australis with increasing anthropogenic disturbances in each of these regions. Although there have been some studies documenting the negative impacts of introduced P. australis, it also plays a beneficial role in some regions, and in some cases, the purported negative impacts are unproven. There is also a broader need to clarify the genetic and ecological relationships between the different introduced sublineages observed in North America, and their relative competitive ability and potential for admixture. This may be done through regional studies that use similar methodologies and share results to uncover common patterns and processes. To our knowledge, such studies have not been performed on P. australis in spite of the broad attention given to this species. Such research could advance theoretical knowledge on biological invasion by helping to determine the extent to which the patterns observed can be generalized or are sublineage specific or region specific. Synthesis Given what appears to be sometimes idiosyncratic invasion patterns when interpreted in isolation in the regions that we analysed, it may

  15. Phragmites australis response to Cu in terms of low molecular weight organic acids (LMWOAs) exudation: Influence of the physiological cycle

    NASA Astrophysics Data System (ADS)

    Rocha, A. Cristina S.; Almeida, C. Marisa R.; Basto, M. Clara P.; Vasconcelos, M. Teresa S. D.

    2014-06-01

    Plant roots have the ability to produce and secrete substances, such as aliphatic low molecular weight organic acids (ALMWOAs), into the rhizosphere for several purposes, including in response to metal contamination. Despite this, little is yet known about the exudation of such substances from marsh plants roots in response to metal exposure. This work aimed at assessing the influence of the physiological cycle of marsh plants on the exudation of ALMWOAs in response to Cu contamination. In vitro experiments were carried out with Phragmites australis specimens, collected in different seasons. Plant roots were exposed to freshwater contaminated with two different Cu concentrations (67 μg/L and 6.9 mg/L), being the ALMWOAs released by the roots measured. Significant differences (both qualitative and quantitative) were observed during the Phragmites australis life cycle. At growing stage, Cu stimulated the exudation of oxalic and formic acids but no significant stimulation was observed for citric acid. At developing stage, exposure to Cu caused inhibition of oxalic acid exudation whereas citric acid liberation was stimulated but only in the media spiked with the lowest Cu concentration tested. At the decaying stage, no significant variation on oxalic acid was observed, whereas the citric and formic acids release increased as a consequence of the plant exposure to Cu. The physiological cycle of Phragmites australis, and probably also of other marsh plants, is therefore an important feature conditioning plants response to Cu contamination, in terms of ALMWOAs exudation. Hence this aspect should be considered when conducting studies on rhizodeposition involving marsh plants exposed to metals and in the event of using marsh plants for phytoremediation purposes in contaminated estuarine areas.

  16. Geographic variation in apparent competition between native and invasive Phragmites australis.

    PubMed

    Bhattarai, Ganesh P; Meyerson, Laura A; Cronin, James T

    2017-02-01

    Apparent competition, the negative interaction between species mediated by shared natural enemies, is thought to play an important role in shaping the structure and dynamics of natural communities. However, its importance in driving species invasions, and whether the strength of this indirect interaction varies across the latitudinal range of the invasion, has not been fully explored. We performed replicated field experiments at four sites spanning 900 km along the Atlantic Coast of the United States to assess the presence and strength of apparent competition between sympatric native and invasive lineages of Phragmites australis. Four herbivore guilds were considered: stem-feeders, leaf-miners, leaf-chewers and aphids. We also tested the hypothesis that the strength of this interaction declines with increasing latitude. Within each site, native and invasive plants of P. australis were cross-transplanted between co-occurring native and invasive patches in the same marsh habitat and herbivore damage was evaluated at the end of the growing season. Apparent competition was evident for both lineages and involved all but the leaf-chewer guild. For native plants, total aphids per plant was 296% higher and the incidence of stem-feeding and leaf-mining herbivores was 34% and 221% higher, respectively, when transplanted into invasive than native patches. These data suggest that invasive P. australis has a negative effect on native P. australis via apparent competition. Averaged among herbivore types, the indirect effects of the invasive lineage on the native lineage was 57% higher than the reverse situation, suggesting that apparent competition was asymmetric. We also found that the strength of apparent competition acting against the native lineage was comparable to the benefits to the invasive lineage from enemy release (i.e., proportionately lower mean herbivory of the invasive relative to the native taxa). Finally, we found the first evidence that the strength of

  17. Leaves of Phragmites australis as potential atmospheric biomonitors of Platinum Group Elements.

    PubMed

    Bonanno, Giuseppe; Pavone, Pietro

    2015-04-01

    The increasing emissions of Platinum Group Elements (PGEs), namely Pt, Pd and Rh, may pose a significant risk to ecosystem processes and human health. A periodic assessment of PGEs distribution in the environment is thus of the utmost importance for the implementation of timely measures of mitigation. Although several studies have quantified PGEs in different life forms such as mammals, birds, fish, crustaceans, algae, mosses and even human beings, data about vascular plants need further surveys. This study aimed to test the suitability of the grass Phragmites australis (common reed) as a biomonitor of PGEs atmospheric pollution. The results showed that Pd and Pt concentrations in leaves are significantly higher in urban areas. In particular, Pd showed the highest range of values in line with current studies that consider palladium as the main element of traffic-related pollution. Overall, the leaves of Phragmites australis reflected the different gradient of PGEs emissions, and may thus be considered as potential biomonitors of atmospheric pollution.

  18. Invading Phragmites australis stimulates methane emissions from North American tidal marshes

    NASA Astrophysics Data System (ADS)

    Mueller, Peter; Meschter, Justin E.; Hager, Rachel N.; Mozdzer, Thomas J.; Jensen, Kai; Langley, J. Adam; Baldwin, Andrew; Megonigal, J. Patrick

    2015-04-01

    Most studies concerned with invasive plant species focus on effects on biodiversity, while only few have investigated how the greenhouse gas balance of an ecosystem or, in particular, how methane emissions are affected by invasion driven shifts in plant species composition. In this study, conducted in brackish marsh sites of the Chesapeake Bay, United States, we investigated the effect of the none-native grass Phragmites australis invading native shortgrass communities on methane emissions. In situ gas flux measurements using static chambers were used to quantify methane emissions along transects of progressive invasion by Phragmites. Methane emissions were several fold higher in Phragmites stands than in adjacent native communities and increased with progressive invasion of Phragmites. Results of a mesocosm experiment support our field observations and show consistently higher methane emissions from mesocoms planted with Phragmites even at different hydrological conditions. Because tidal marshes, as blue carbon ecosystems, sequester soil carbon rapidly and emit methane slowly compared to other wetland ecosystems, they are increasingly recognized as having a high carbon value. Our results indicate that the replacement of native marsh communities by Phragmites may considerably change the green house gas balance of these ecosystems and thus lower their carbon sequestration value.

  19. Native and European haplotypes of Phragmites Australis (common reed) in the central Platte River, Nebraska

    USGS Publications Warehouse

    Larson, D.L.; Galatowitsch, S.M.; Larson, J.L.

    2011-01-01

    Phragmites australis (common reed) is known to have occurred along the Platte River historically, but recent rapid increases in both distribution and density have begun to impact habitat for migrating sandhill cranes and nesting piping plovers and least terns. Invasiveness in Phragmites has been associated with the incursion of a European genotype (haplotype M) in other areas; determining the genotype of Phragmites along the central Platte River has implications for proper management of the river system. In 2008 we sampled Phragmites patches along the central Platte River from Lexington to Chapman, NE, stratified by bridge segments, to determine the current distribution of haplotype E (native) and haplotype M genotypes. In addition, we did a retrospective analysis of historical Phragmites collections from the central Platte watershed (1902-2006) at the Bessey Herbarium. Fresh tissue from the 2008 survey and dried tissue from the herbarium specimens were classified as haplotype M or E using the restriction fragment length polymorphism procedure. The European haplotype was predominant in the 2008 samples: only 14 Phragmites shoots were identified as native haplotype E; 224 were non-native haplotype M. The retrospective analysis revealed primarily native haplotype individuals. Only collections made in Lancaster County, near Lincoln, NE, were haplotype M, and the earliest of these was collected in 1973. ?? 2011 Copyright by the Center for Great Plains Studies, University of Nebraska-Lincoln.

  20. Identification, Development, and Release of Insect Biocontrol Agents for the Management of Phragmites australis

    DTIC Science & Technology

    2014-07-01

    ER D C/ EL C R- 14 -2 Aquatic Plant Control Research Program Identification, Development, and Release of Insect Biocontrol Agents for...ERDC/EL CR-14-2 July 2014 Identification, Development, and Release of Insect Biocontrol Agents for the Management of Phragmites australis Bernd...and (5) assess the extent of hybridization between native and introduced genotypes. All selected insect species are stem miners that overwinter as

  1. Vegetative ecological characteristics of restored reed (Phragmites australis) wetlands in the Yellow River Delta, China.

    PubMed

    Wang, Xuehong; Yu, Junbao; Zhou, Di; Dong, Hongfang; Li, Yunzhao; Lin, Qianxin; Guan, Bo; Wang, Yongli

    2012-02-01

    In this study, we compared ecological characteristics of wetland vegetation in a series of restoration projects that were carried out in the wetlands of Yellow River Delta. The investigated characteristics include plant composition structure, species diversity and community similarity in three kinds of Phragmites australis wetlands, i.e. restored P. australis wetlands (R1, R2, R3 and R4: restored in 2002, 2005, 2007 and 2009, respectively), natural P. australis wetland (N) and degraded P. australis wetland (D) to assess the process of wetlands restoration. The coverage of the R1 was 99%, which was similar to natural wetland. Among all studied wetlands, the highest and lowest stem density was observed in R1 and R2, respectively, Plant height and stem diameter show the same trend as N > R2 > R1 > R3 > D > R4. Species diversity of restored P. australis wetlands became closed to natural wetland. Both species richness and Shannon-Wiener index had similar tendency: increased first and then decreased with restored time. The highest species richness and species diversity were observed in R2, while the lowest values of those parameters were found in natural P. australis wetland. Similarity indexes between restored wetlands and natural wetland increased with the restoration time, but they were still less than 50%. The results indicate that the vegetation of P. australis wetlands has experienced a great improvement after several years' restoration, and it is feasible to restored degraded P. australis wetlands by pouring fresh water into those wetlands in the Yellow River Delta. However, it is notable that costal degraded P. australis wetland in this region may take years to decades to reach the status of natural wetland.

  2. Seasonal transpiration pattern of Phragmites australis in a wetland of semi-arid Spain

    NASA Astrophysics Data System (ADS)

    Moro, María José; Domingo, Francisco; López, Germán

    2004-02-01

    Transpiration rates were measured in a flooded population of Phragmites australis ssp. altissima in a wetland located in El Hondo Natural Park (southeastern Spain) during the growing season of 2000. The heat balance method for measuring sap flow was used to calculate the rate of water transpiration on a whole-stem basis. Four series of measurements were carried out in selected weeks in May, June, August and October. Structure, biomass and leaf area index of the reed population were simultaneously quantified in order to scale transpiration on a plot-area basis.Overall, transpiration flux was high during the sampling period and showed a typical diurnal pattern with a maximum at about midday. Mean transpiration was highest at the end of June coinciding with the peak of reed growth and with the maximum leaf area both at individual and plot scales. Rates decreased abruptly in October, in parallel with the advanced foliar senescence. The variation of both midday and integrated daily transpiration is significantly related to that of the air temperature on clear days. Cloudy and rainy days exert a pronounced effect on water loss by decreasing transpiration. Our results highlight the potential use of the sap-flow method to measure transpiration in reed ecosystems and the relevance of this flux for the water balance in wetlands in semi-arid environments. Thus, it is suggested that water management in these areas could be favoured by acquiring high-quality experimental data.

  3. Archaeal communities associated with roots of the common reed (Phragmites australis) in Beijing Cuihu Wetland.

    PubMed

    Liu, Yin; Li, Hong; Liu, Qun Fang; Li, Yan Hong

    2015-05-01

    The richness, phylogeny and composition of archaeal community associated with the roots of common reed (Phragmites australis) growing in the Beijing Cuihu Wetland, China was investigated using a 16S rDNA library. In total, 235 individual sequences were collected, and a phylogenetic analysis revealed that 69.4 and 11.5 % of clones were affiliated with the Euryarchaeota and the Crenarchaeota, respectively. In Euryarchaeota, the archaeal community was dominated by species in following genera: Methanobacterium in the order Methanobacteriales (60.7 %); Methanoregula and Methanospirillum in the order Methanomicrobiales (20.2 %), and Methanomethylovorans, Methanosarcina and Methanosaeta in the order Methanosarcinales (17.2 %). Of 27 sequences assigned to uncultured Crenarchaeota, 22 were grouped into Group 1.3, and five grouped into Group 1.1b. Hence, the archaeal communities associated with reed roots are largely involved in methane production, and, to a lesser extent, in ammonia oxidization. Quantification of the archaeal amoA gene indicated that ammonia oxidizing archaea were more numerous in the rhizosphere soil than in the root tissue or surrounding water. A total of 19.1 % of the sequences were unclassified, suggesting that many unidentified archaea are probably involved in the reed wetland ecosystem.

  4. Antioxidant response to metal pollution in Phragmites australis from Anzali wetland.

    PubMed

    Esmaeilzadeh, Marjan; Karbassi, Abdolreza; Bastami, Kazem Darvish

    2017-03-21

    This research was conducted to examine variations of antioxidant enzyme activity in Phragmites australis as a biomarker for metals such as As, Pb, Cu, and Cd. Samples of sediment and plants were collected from 7 stations located in Anzali wetland. Biochemical parameters including Catalase, Peroxidase and Ascorbate Peroxidase activity were analyzed in the roots, stems and leaves of P. australis. The obtained results indicated that there were significant differences among activities of antioxidant enzymes in three organs (p<0.05). Antioxidant enzyme activities in the organs for all studied stations were as the following order: stemaustralis. As a result, it can be concluded from this study that antioxidant enzymes are good biomarkers reflecting metal contamination in sediments of Anzali wetland.

  5. Density-dependent role of an invasive marsh grass, Phragmites australis, on ecosystem service provision

    PubMed Central

    Puckett, Brandon J.; Theuerkauf, Kathrynlynn W.; Theuerkauf, Ethan J.; Eggleston, David B.

    2017-01-01

    Invasive species can positively, neutrally, or negatively affect the provision of ecosystem services. The direction and magnitude of this effect can be a function of the invaders’ density and the service(s) of interest. We assessed the density-dependent effect of an invasive marsh grass, Phragmites australis, on three ecosystem services (plant diversity and community structure, shoreline stabilization, and carbon storage) in two oligohaline marshes within the North Carolina Coastal Reserve and National Estuarine Research Reserve System (NCNERR), USA. Plant species richness was equivalent among low, medium and high Phragmites density plots, and overall plant community composition did not vary significantly by Phragmites density. Shoreline change was most negative (landward retreat) where Phragmites density was highest (-0.40 ± 0.19 m yr-1 vs. -0.31 ± 0.10 for low density Phragmites) in the high energy marsh of Kitty Hawk Woods Reserve and most positive (soundward advance) where Phragmites density was highest (0.19 ± 0.05 m yr-1 vs. 0.12 ± 0.07 for low density Phragmites) in the lower energy marsh of Currituck Banks Reserve, although there was no significant effect of Phragmites density on shoreline change. In Currituck Banks, mean soil carbon content was approximately equivalent in cores extracted from low and high Phragmites density plots (23.23 ± 2.0 kg C m-3 vs. 22.81 ± 3.8). In Kitty Hawk Woods, mean soil carbon content was greater in low Phragmites density plots (36.63 ± 10.22 kg C m-3) than those with medium (13.99 ± 1.23 kg C m-3) or high density (21.61 ± 4.53 kg C m-3), but differences were not significant. These findings suggest an overall neutral density-dependent effect of Phragmites on three ecosystem services within two oligohaline marshes in different environmental settings within a protected reserve system. Moreover, the conceptual framework of this study can broadly inform an ecosystem services-based approach to invasive species management

  6. Density-dependent role of an invasive marsh grass, Phragmites australis, on ecosystem service provision.

    PubMed

    Theuerkauf, Seth J; Puckett, Brandon J; Theuerkauf, Kathrynlynn W; Theuerkauf, Ethan J; Eggleston, David B

    2017-01-01

    Invasive species can positively, neutrally, or negatively affect the provision of ecosystem services. The direction and magnitude of this effect can be a function of the invaders' density and the service(s) of interest. We assessed the density-dependent effect of an invasive marsh grass, Phragmites australis, on three ecosystem services (plant diversity and community structure, shoreline stabilization, and carbon storage) in two oligohaline marshes within the North Carolina Coastal Reserve and National Estuarine Research Reserve System (NCNERR), USA. Plant species richness was equivalent among low, medium and high Phragmites density plots, and overall plant community composition did not vary significantly by Phragmites density. Shoreline change was most negative (landward retreat) where Phragmites density was highest (-0.40 ± 0.19 m yr-1 vs. -0.31 ± 0.10 for low density Phragmites) in the high energy marsh of Kitty Hawk Woods Reserve and most positive (soundward advance) where Phragmites density was highest (0.19 ± 0.05 m yr-1 vs. 0.12 ± 0.07 for low density Phragmites) in the lower energy marsh of Currituck Banks Reserve, although there was no significant effect of Phragmites density on shoreline change. In Currituck Banks, mean soil carbon content was approximately equivalent in cores extracted from low and high Phragmites density plots (23.23 ± 2.0 kg C m-3 vs. 22.81 ± 3.8). In Kitty Hawk Woods, mean soil carbon content was greater in low Phragmites density plots (36.63 ± 10.22 kg C m-3) than those with medium (13.99 ± 1.23 kg C m-3) or high density (21.61 ± 4.53 kg C m-3), but differences were not significant. These findings suggest an overall neutral density-dependent effect of Phragmites on three ecosystem services within two oligohaline marshes in different environmental settings within a protected reserve system. Moreover, the conceptual framework of this study can broadly inform an ecosystem services-based approach to

  7. Assessment of suitable habitat for Phragmites australis (common reed) in the Great Lakes coastal zone

    USGS Publications Warehouse

    Carlson Mazur, Martha L.; Kowalski, Kurt P.; Galbraith, David

    2014-01-01

    In the Laurentian Great Lakes, the invasive form of Phragmites australis (common reed) poses a threat to highly productive coastal wetlands and shorelines by forming impenetrable stands that outcompete native plants. Large, dominant stands can derail efforts to restore wetland ecosystems degraded by other stressors. To be proactive, landscape-level management of Phragmites requires information on the current spatial distribution of the species and a characterization of areas suitable for future colonization. Using a recent basin-scale map of this invasive plant’s distribution in the U.S. coastal zone of the Great Lakes, environmental data (e.g., soils, nutrients, disturbance, climate, topography), and climate predictions, we performed analyses of current and predicted suitable coastal habitat using boosted regression trees, a type of species distribution modeling. We also investigated differential influences of environmental variables in the upper lakes (Lakes Superior, Michigan, and Huron) and lower lakes (Lakes St. Clair, Erie, and Ontario). Basin-wide results showed that the coastal areas most vulnerable to Phragmites expansion were in close proximity to developed lands and had minimal topographic relief, poorly drained soils, and dense road networks. Elevated nutrients and proximity to agriculture also influenced the distribution of Phragmites. Climate predictions indicated an increase in suitable habitat in coastal Lakes Huron and Michigan in particular. The results of this study, combined with a publicly available online decision support tool, will enable resource managers and restoration practitioners to target and prioritize Phragmites control efforts in the Great Lakes coastal zone.

  8. Mapping an invasive plant, Phragmites australis, in coastal wetlands using the EO-1 Hyperion hyperspectral sensor

    USGS Publications Warehouse

    Pengra, B.W.; Johnston, C.A.; Loveland, T.R.

    2007-01-01

    Mapping tools are needed to document the location and extent of Phragmites australis, a tall grass that invades coastal marshes throughout North America, displacing native plant species and degrading wetland habitat. Mapping Phragmites is particularly challenging in the freshwater Great Lakes coastal wetlands due to dynamic lake levels and vegetation diversity. We tested the applicability of Hyperion hyperspectral satellite imagery for mapping Phragmites in wetlands of the west coast of Green Bay in Wisconsin, U.S.A. A reference spectrum created using Hyperion data from several pure Phragmites stands within the image was used with a Spectral Correlation Mapper (SCM) algorithm to create a raster map with values ranging from 0 to 1, where 0 represented the greatest similarity between the reference spectrum and the image spectrum and 1 the least similarity. The final two-class thematic classification predicted monodominant Phragmites covering 3.4% of the study area. Most of this was concentrated in long linear features parallel to the Green Bay shoreline, particularly in areas that had been under water only six years earlier when lake levels were 66??cm higher. An error matrix using spring 2005 field validation points (n = 129) showed good overall accuracy-81.4%. The small size and linear arrangement of Phragmites stands was less than optimal relative to the sensor resolution, and Hyperion's 30??m resolution captured few if any pure pixels. Contemporary Phragmites maps prepared with Hyperion imagery would provide wetland managers with a tool that they currently lack, which could aid attempts to stem the spread of this invasive species. ?? 2006 Elsevier Inc. All rights reserved.

  9. Cellulosic butanol production from alkali-pretreated switchgrass (Panicum virgatum) and phragmites (Phragmites australis).

    PubMed

    Gao, Kai; Boiano, Simone; Marzocchella, Antonio; Rehmann, Lars

    2014-12-01

    A potential dedicated energy crop (switchgrass) and an invasive (North America) plant species (phragmites) were compared as potential substrates for acetone butanol ethanol (ABE) fermentation. Both biomass were pretreated with 1% (w/v) NaOH and subjected to enzymatic hydrolysis. Total reducing sugar yields were 365 and 385gkg(-1) raw biomass for switchgrass and phragmites. Fermentation of the hydrolysates resulted in overall ABE yields of 146 and 150gkg(-1) (per kg dry plant material), with a theoretical maximum of 189 and 208gkg(-1), respectively. Though similar overall solvent yields were obtained from both crops, the largest carbon loss in the case of switchgrass occurred during pretreatment, while the largest loss in the case of phragmites occurred to enzymatic hydrolysis. These findings suggest that higher overall yields are achievable and that both crops are suitable feedstocks for butanol fermentation.

  10. Archaeal rhizosphere communities differ between the native and invasive lines of the wetland plant phragmites australis (common reed) in a Chesapeake Bay subestuary

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Phragmites australis, a common wetland plant species worldwide, is best known in North America as persistent invasive species. Only in recent decades was a native line, Phragmites australis subsp. americanus, confirmed in North American wetlands. This study investigated whether the two lines suppo...

  11. Heavy metals in sediments and their bioaccumulation in Phragmites australis in the Anzali wetland of Iran

    NASA Astrophysics Data System (ADS)

    Esmaeilzadeh, Marjan; Karbassi, Abdolreza; Moattar, Faramarz

    2016-07-01

    Accumulation of metals in both sediments and Phragmites australis organs was studied. Samples were collected from seven stations located in Anzali wetland, Iran. The samples were analyzed by inductively coupled plasma mass spectrometry (ICP-MS). The results showed that concentration of the studied metals (except As and Cd) were higher in sediments than in P. australis organs. Metal accumulation was found to be significantly ( P <0.05) higher in roots than in above-ground organs of P. australis. The bioaccumulation factor (BAF) and the transfer factor (TF) also verified the highest rate of metal accumulation in roots and their reduced mobility from roots to the above-ground organs. Pearson correlation coefficient showed significant relationships between metal concentrations in sediments and those in plant organs. It should be pointed out that sediment and plant samples exhibited higher metal concentrations in eastern and central parts than in western and southern parts of the wetland. The mean concentrations of all studied elements (except for Fe, V and Al) were higher in these sediment samples than in the Earth's crust and shale. High accumulation of metals in P. australis organs (roots and shoots) is indicative of their high bioavailability in sediments of the wetland. The correlation between metal concentrations in sediments and in P. australis indicates that plant organs are good bioindicators of metal pollution in sediments of Anzali wetland.

  12. Water and Energy Balance in Response to the Removal of Invasive Phragmites Australis in a Riparian Wetland

    NASA Astrophysics Data System (ADS)

    Mykleby, P.; Lenters, J. D.; Cutrell, G. J.; Herrman, K.; Istanbulluoglu, E.; Scott, D.

    2011-12-01

    Vegetation plays an important role in the surface energy and water balance of wetlands. Transpiration from phreatophytes, in particular, withdraws water directly from groundwater, often impacting streamflow rates in adjacent tributaries. In the Republican River basin of the Central Plains (USA), streamflow has declined significantly in the past 30-40 years. Invasive vegetation species (such as Phragmites australis) have been removed from portions of the riparian corridor in an effort to halt or reverse the downward trend in streamflow. In this study, we investigated the energy and water balance of a P. australis-dominated riparian wetland in south-central Nebraska to assess the potential effectiveness of such an approach. Evapotranspiration (ET) rates were measured during two growing seasons - one being 2009, when the P. australis was at full growth, and the other during 2010, after the vegetation had been sprayed with herbicide (and remained only as dead, standing biomass). Energy balance measurements at the field site included net radiation, heat storage rates in the canopy, soil, and standing water, and sensible heat flux, which was measured using a large-aperture scintillometer (LAS). Latent heat flux (i.e., ET) was calculated as a residual of the energy balance, and comparisons were made between the two growing seasons. As a result of the spraying of the P. australis vegetation, season-mean ET rates dropped from 4.4 mm day-1 in 2009 to 3.0 mm day-1 in 2010. This decrease in ET was associated with a large increase in sensible heat flux, which more than doubled between the two years (from 33 W m-2 in 2009 to 76 W m-2 in 2010). Meteorological conditions at the site were slightly different from one year to the next, but the differences were not large enough to account for the dramatic changes in latent and sensible heat flux that were observed. We conclude, therefore, that the majority of the ~30% decrease in ET (and ~130% increase in sensible heat flux) was the

  13. Assessment of rhizospheric culturable bacteria of Phragmites australis and Juncus effusus from polluted sites.

    PubMed

    Pereira, Sofia I A; Pires, Carlos; Henriques, Isabel; Correia, António; Magan, Naresh; Castro, Paula M L

    2015-10-01

    This study aimed at the isolation and characterization of metal(loid)-tolerant bacteria from the rhizosphere of Phragmites australis and Juncus effusus plants growing in two long-term contaminated sites in Northern Portugal. Site 1 had higher contamination than Site 3. Bacteria were isolated using metal(loid)-supplemented (Cd, Zn, and As) media. Isolates were grouped by random amplified polymorphic DNA and identified by 16S rRNA gene sequencing. Strains were also examined for their metal(loid) tolerance. The counts of metal(loid)-tolerant bacteria were higher in Site 1 and ranged between log 7.17 CFU g(-1) soil in As-containing medium and log 7.57 CFU g(-1) soil in Zn-containing medium, while counts at Site 3 varied between log 5.33 CFU g(-1) soil in Cd-containing medium and log 6.97 CFU g(-1) soil in As-containing medium. The composition of bacterial populations varied between locations. In Site 1, the classes Actinobacteria (36%) and Bacilli (24%) were well represented, while in Site 3 strains were mainly affiliated to classes Actinobacteria (35%), γ-Proteobacteria (35%), and β-Proteobacteria (12%). The order of metal(loid) toxicity for the isolated strains was Cd > As > Zn. Overall, 10 strains grew at 500 mg Cd L(-1) , 1000 mg Zn L(-1) , and 500 mg As L(-1) , being considered the most metal(loid)-tolerant bacteria. These strains belonged to genera Cupriavidus, Burkholderia, Novosphingobium, Sphingobacterium, Castellaniella, Mesorhizobium, Chryseobacterium, and Rhodococcus and were mainly retrieved from Site 1. The multiple metal(loid)-tolerant strains isolated in this study have potential to be used in bioremediation/phytoremediation.

  14. Preadaptation and post-introduction evolution facilitate the invasion of Phragmites australis in North America.

    PubMed

    Guo, Wen-Yong; Lambertini, Carla; Nguyen, Loc Xuan; Li, Xiu-Zhen; Brix, Hans

    2014-12-01

    Compared with non-invasive species, invasive plant species may benefit from certain advantageous traits, for example, higher photosynthesis capacity and resource/energy-use efficiency. These traits can be preadapted prior to introduction, but can also be acquired through evolution following introduction to the new range. Disentangling the origins of these advantageous traits is a fundamental and emerging question in invasion ecology. We conducted a multiple comparative experiment under identical environmental condition with the invasive haplotype M lineage of the wetland grass Phragmites australis and compared the ecophysiological traits of this invasive haplotype M in North America with those of the European ancestor and the conspecific North American native haplotype E lineage, P. australis ssp. americanus. The invasive haplotype M differed significantly from the native North American conspecific haplotype E in several ecophysiological and morphological traits, and the European haplotype M had a more efficient photosynthetic apparatus than the native North American P. australis ssp. americanus. Within the haplotype M lineage, the introduced North American P. australis exhibited different biomass allocation patterns and resource/energy-use strategies compared to its European ancestor group. A discriminant analysis of principal components separated the haplotype M and the haplotype E lineages completely along the first canonical axis, highly related to photosynthetic gas-exchange parameters, photosynthetic energy-use efficiency and payback time. The second canonical axis, highly related to photosynthetic nitrogen use efficiency and construction costs, significantly separated the introduced P. australis in North America from its European ancestor. Synthesis. We conclude that the European P. australis lineage was preadapted to be invasive prior to its introduction, and that the invasion in North America is further stimulated by rapid post-introduction evolution in

  15. Preadaptation and post-introduction evolution facilitate the invasion of Phragmites australis in North America

    PubMed Central

    Guo, Wen-Yong; Lambertini, Carla; Nguyen, Loc Xuan; Li, Xiu-Zhen; Brix, Hans

    2014-01-01

    Compared with non-invasive species, invasive plant species may benefit from certain advantageous traits, for example, higher photosynthesis capacity and resource/energy-use efficiency. These traits can be preadapted prior to introduction, but can also be acquired through evolution following introduction to the new range. Disentangling the origins of these advantageous traits is a fundamental and emerging question in invasion ecology. We conducted a multiple comparative experiment under identical environmental condition with the invasive haplotype M lineage of the wetland grass Phragmites australis and compared the ecophysiological traits of this invasive haplotype M in North America with those of the European ancestor and the conspecific North American native haplotype E lineage, P. australis ssp. americanus. The invasive haplotype M differed significantly from the native North American conspecific haplotype E in several ecophysiological and morphological traits, and the European haplotype M had a more efficient photosynthetic apparatus than the native North American P. australis ssp. americanus. Within the haplotype M lineage, the introduced North American P. australis exhibited different biomass allocation patterns and resource/energy-use strategies compared to its European ancestor group. A discriminant analysis of principal components separated the haplotype M and the haplotype E lineages completely along the first canonical axis, highly related to photosynthetic gas-exchange parameters, photosynthetic energy-use efficiency and payback time. The second canonical axis, highly related to photosynthetic nitrogen use efficiency and construction costs, significantly separated the introduced P. australis in North America from its European ancestor. Synthesis. We conclude that the European P. australis lineage was preadapted to be invasive prior to its introduction, and that the invasion in North America is further stimulated by rapid post-introduction evolution in

  16. Genetics, novel weapons and rhizospheric microcosmal signaling in the invasion of Phragmites australis

    PubMed Central

    Rudrappa, Thimmaraju

    2008-01-01

    Chemical communication and perception strategies between plants are highly sophisticated but are only partly understood. Among the different interactions, the suppressive interaction of a class of chemicals released by one plant through root exudates against the neighbouring plants (allelopathy) have been implicated in the invasiveness of many exotic weedy species. Phragmites australis (common reed) is one of the dominant colonizers of the North American wetland marshes and exhibits invasive behavior by virtually replacing the entire native vegetation in its niche. Recently, by adopting a systematic bioassay driven approach we elucidated the role of root derived allelopathy as one of the important mechanisms by which P. australis exerts its invasive behavior. Additionally, our recent preliminary data indicates the involvement of rhizobacterial signaling in the invasive success of P. australis. A better understanding of biochemical weaponry used by P. australis will aid scientists and technologists in addressing the impact of root secretions in invasiveness of weedy species and thus promote a more informed environmental stewardship. PMID:19516974

  17. Detecting and Mapping Invasive Phragmites australis in the coastal Great Lakes with ALOS PALSAR imagery

    NASA Astrophysics Data System (ADS)

    Bourgeau-chavez, L. L.; Scarbrough, K.; Jenkins, L. K.; Riordan, K.; Powell, R. B.; Brooks, C.; Kowalski, K.; Carlson Mazur, M.; Huberty, B.

    2011-12-01

    Phragmites australis is a non-native invasive plant that can form dense monocultures, causing negative impacts on coastal Great Lakes wetlands by reducing ecosystem services including habitat and therefore, biological diversity. Through Great Lakes Restoration Initiative funding, ALOS PALSAR imagery is being used to map the invasive plant as it occurs in monoculture stands of the U.S. coastal Great Lakes wetlands. These invasive Phragmites maps are being used as part of a USGS Great Lakes Science Center (GLSC) and US Fish and Wildlife Service (USFWS) National Wetlands Inventory (NWI) program to identify major environmental drivers of invasive Phragmites distribution, to assess areas vulnerable to new invasion, and to provide this information to regional stakeholders through a decision support tool. The invasive Phragmites map is the first U.S. basin-wide map to be produced on the distribution of this species. Methods include maximum likelihood classification of multi-season ALOS PALSAR HH and HV polarization data. PALSAR is an L-band (23 cm wavelength) imaging radar sensor which is sensitive to differences in plant biomass and inundation patterns, allowing for the extraction of these tall (up to 15 m), high-density, high-biomass Phragmites wetland stands. To improve discrimination of Phragmites australis, the three date (spring, summer, fall) dataset is being used, which takes advantage of phenological changes in vegetation and inundation patterns over the seasons. Field collections of training and randomly selected validation data were conducted in spring summer and fall of 2010-11 to aid in the mapping and for accuracy assessment. The minimum mapping unit is 1/2 acre and thus all field sites were sampled at 1/2 acre units. All map products and field validation data will be complete by December 2011. Maps are being completed on a Lake basin basis. The first final map product was delivered for Lake Erie coastal wetlands to 10 km inland, with an overall map accuracy

  18. Rapid growth of a Eurasian haplotype of Phragmites australis in a restored brackish marsh in Louisiana, USA

    USGS Publications Warehouse

    Howard, R.J.; Travis, S.E.; Sikes, B.A.

    2008-01-01

    While numerous studies have documented patterns of invasion by non-indigenous plant species, few have considered the invasive properties of non-native genotypes of native species. Characteristics associated with specific genotypes, such as tolerance to disturbance, may mistakenly be applied to an entire species in the absence of genetic information, which consequently may affect management decisions. We report here on the incidence and growth of an introduced lineage of Phragmites australis in the Gulf of Mexico coastal zone of Louisiana. P. australis was collected from nine separate locations for inclusion in a series of growth experiments. Chloroplast DNA analysis indicated that specimens collected from four locations in the Mississippi River Delta represented the introduced Eurasian haplotype; the remainder represented the gulf coast haplotype. Three distinct genotypes, or clones, were identified within each haplotype via analysis using amplified fragment length polymorphisms, which also revealed reduced genetic diversity of the gulf coast clones compared to the Eurasian clones. Clones of each haplotype were planted along with three other native macrophytes at similar densities in a restored brackish marsh and monitored for growth. After 14 months, the Eurasian haplotype had spread vegetatively to cover about 82% of the experimental plots, more than four times the coverage (18%) of the gulf coast haplotype. Thus, the use of P. australis plantings for wetland restoration should consider the genetic lineage of plants used since our results indicate the potential of the Eurasian haplotype to grow rapidly at newly restored sites. This rapid growth may limit the establishment of more slowly growing native species. ?? 2007 Springer Science+Business Media B.V.

  19. Silicon supply modifies C:N:P stoichiometry and growth of Phragmites australis.

    PubMed

    Schaller, J; Brackhage, C; Gessner, M O; Bäuker, E; Gert Dudel, E

    2012-03-01

    Silicon is a non-essential element for plant growth. Nevertheless, it affects plant stress resistance and in some plants, such as grasses, it may substitute carbon (C) compounds in cell walls, thereby influencing C allocation patterns and biomass production. How variation in silicon supply over a narrow range affects nitrogen (N) and phosphorus (P) uptake by plants has also been investigated in some detail. However, little is known about effects on the stoichiometric relationships between C, N and P when silicon supply varies over a broader range. Here, we assessed the effect of silicon on aboveground biomass production and C:N:P stoichiometry of common reed, Phragmites australis, in a pot experiment in which three widely differing levels of silicon were supplied. Scanning electron microscopy (SEM) showed that elevated silicon supply promoted silica deposition in the epidermis of Phragmites leaves. This resulted in altered N:P ratios, whereas C:N ratios changed only slightly. Plant growth was slightly (but not significantly) enhanced at intermediate silicon supply levels but significantly decreased at high levels. These findings point to the potential of silicon to impact plant growth and elemental stoichiometry and, by extension, to affect biogeochemical cycles in ecosystems dominated by Phragmites and other grasses and sedges.

  20. Phragmites australis and Typha orientalis in removal of pollutant in Taihu Lake, China.

    PubMed

    Tian, Ziqiang; Zheng, Binghui; Liu, Meizhen; Zhang, Zhenyu

    2009-01-01

    Two plant populations of Phragmites australis and Typha orientalis grown in gravel and sediment substrate were studied to assess their capabilities for purifying polluted water in Taihu Lake, China. The substrate displayed most significant effects on the suspended matter (P < 0.01), with the reduction of 76%-87% and 52%-63% for P. australis, and 83%-86% and 45%-62% for T. orientalis in gravel substrate and sediment substrate, respectively. Both species and substrates significantly decreased the N and P concentrations of water body (P < 0.01). P. australis showed higher total N and P concentrations in tissues than T. orientalis and had a greater potential to remove nutrients from the lake. Phosphate was easily to concentrate in the belowground tissues, while nitrate concentration was higher in leaf and stalk. Therefore, harvesting the aboveground tissues could take most of nitrate out of the sediment. The saturate photosynthetic rate (Asat) of P. australis was higher than that of T. orientalis when grown in sediment substrate. But instance water-use-efficiency (WUEi) (A/E) and intrinsic water use efficiency (A/gs) showed the maximum values of two species grown in river water. With significant difference in gs, however, intercellular CO2 concentration (Ci) had no obvious difference in two species which indicated that high Asat value of P. australis might result from the increased carboxylation capacity of the mesophyll, because of the central role of N in photosynthetic enzymes. Our findings suggest that the plants could absorb most of nitrogen in polluted water, while gravel displayed a high capacity for absorbing the suspended matters and phosphate salts. Therefore, biological and physiological pathways for pollutant removal should be integrated.

  1. Soil As Levels and Bioaccumulation in Suaeda salsa and Phragmites australis Wetlands of the Yellow River Estuary, China

    PubMed Central

    Wang, Junjing; Bai, Junhong; Gao, Zhaoqin; Lu, Qiongqiong; Zhao, Qingqing

    2015-01-01

    Little information is available on As contamination dynamics in the soil-plant systems of wetlands. Total arsenic (As) in soil and plant samples from Suaeda salsa and Phragmites australis wetlands was measured in the Yellow River Estuary (YRE) in summer and autumn of 2007 to investigate the seasonal changes in As concentrations in different wetlands. The results showed that soil As levels greatly exceeded the global and regional background values. As levels in soil and the roots and stems of both types of plants were much higher in summer than in autumn, whereas leaf As showed higher level in autumn. Soil sulfur was the main factor influencing As levels in Suaeda salsa wetlands, whereas soil porosity was the most important factor for Phragmites australis wetlands. The contamination factor (CF) showed moderately to considerably polluted levels of As in both wetland soils. Plant roots and leaves of Suaeda salsa had higher As concentrations and biological concentration factors (BCFs) than stems, while the leaves and stems of Phragmites australis showed higher As levels and BCFs than roots. Compared to Phragmites australis, Suaeda salsa generally showed higher translocation factor (TF), while TF values for both plant species were higher in summer than in autumn. PMID:25685781

  2. Genome Sequence of Photobacterium halotolerans MELD1, with Mercury Reductase (merA), Isolated from Phragmites australis.

    PubMed

    Mathew, Dony Chacko; Mathew, Gincy Marina; Gicana, Ronnie Gicaraya; Huang, Chieh-Chen

    2015-06-04

    Here, we present the whole-genome sequence of Photobacterium halotolerans strain, MELD1, isolated from the roots of a terrestrial plant Phragmites australis grown in soil heavily contaminated with mercury and dioxin. The genome provides further insight into the adaptation of bacteria to the toxic environment from where it was isolated.

  3. Comparing the efficiency of Cyperus alternifolius and Phragmites australis in municipal wastewater treatment by subsurface constructed wetland.

    PubMed

    Shahi, Davod Hossein; Eslami, Hadi; Ehrampoosh, Mohamad Hasan; Ebrahimi, Asghar; Ghaneian, Mohamad Taghy; Ayatollah, Shirin; Mozayan, Mohamad Reza

    2013-04-15

    Nowadays, application of natural wastewater treatment systems such as wetland not only reduces economic costs and energy consumption, but also decreases environmental pollution. This study aimed to compare efficiency of Cyperus alternifolius and Phragmites australis in Municipal wastewater treatment by Subsurface Constructed Wetland Method. This is an applied-interventionnal study in which three reactors (control pilot, Cyperus alternifolius (umbrella palm) plant pilot and Phragmites australis (reed) plant pilot were designed by subsurface constructed wetland method. Then 90 samples were taken from input and output of reactors with four-day retention time. These samples were tested and finally the data were analyzed by Paired Sample Test statistical analysis. The results showed that removal efficiency of the parameters such as COD, BOD5, TSS, NO3-N, NH3-N, PO4-P, total coliform and fecal coliform was 74, 73, 84, 40, 36, 70, 33 and 38% in Cyperus alternifolius plant wetland, 44, 34, 77, 15, 0.3, 1, 17 and 26% in control wetland and 59, 54, 73, 6, 3, 10, 93 and 50 in Phragmites australis plant wetland, respectively. This reduction rate in all parameters- except fecal coliform- was statistically significant (p = 0.05). The results of this study showed that Cyperus alternifolius plant had higher efficiency in the removal of chemical parameters, whereas Phragmites australis plant had appropriate efficiency in the removal of microbiological parameters. Therefore, it can be concluded that application of these two plants can be effective in wastewater treatment.

  4. Soil as levels and bioaccumulation in Suaeda salsa and Phragmites australis wetlands of the Yellow River Estuary, China.

    PubMed

    Wang, Junjing; Bai, Junhong; Gao, Zhaoqin; Lu, Qiongqiong; Zhao, Qingqing

    2015-01-01

    Little information is available on As contamination dynamics in the soil-plant systems of wetlands. Total arsenic (As) in soil and plant samples from Suaeda salsa and Phragmites australis wetlands was measured in the Yellow River Estuary (YRE) in summer and autumn of 2007 to investigate the seasonal changes in As concentrations in different wetlands. The results showed that soil As levels greatly exceeded the global and regional background values. As levels in soil and the roots and stems of both types of plants were much higher in summer than in autumn, whereas leaf As showed higher level in autumn. Soil sulfur was the main factor influencing As levels in Suaeda salsa wetlands, whereas soil porosity was the most important factor for Phragmites australis wetlands. The contamination factor (CF) showed moderately to considerably polluted levels of As in both wetland soils. Plant roots and leaves of Suaeda salsa had higher As concentrations and biological concentration factors (BCFs) than stems, while the leaves and stems of Phragmites australis showed higher As levels and BCFs than roots. Compared to Phragmites australis, Suaeda salsa generally showed higher translocation factor (TF), while TF values for both plant species were higher in summer than in autumn.

  5. The Effect of Artificial Mowing on the Competition of Phragmites australis and Spartina alterniflora in the Yangtze Estuary

    PubMed Central

    Zhang, Chao

    2017-01-01

    Spartina alterniflora Loisel. is one of the most invasive species in the world. However, little is known about the role of artificial mowing in its invasiveness and competiveness. In this work, we studied the effect of mowing on its interspecific interactions with native species Phragmites australis (Cav.) Trin ex Steud of the Yangtze Estuary, China. We calculated their relative neighbor effect (RNE) index, effect of relative crowding (Dr) index, and interaction strength (I) index. The results showed that the RNE of Phragmites australis and Spartina alterniflora was 0.354 and 0.619, respectively, and they have competitive interactions. The mowing treatments can significantly influence the RNE of Phragmites australis and Spartina alterniflora on each other. Concretely, the RNE of Spartina alterniflora in the removal treatments was significantly higher than the value in the controls. But the RNE of Phragmites australis in the removal treatments was significantly lower than the value in the controls. Meanwhile, Dr of the two species on the targets was higher in the removal treatments than that in the controls, and the opposite was for I. We concluded that artificial mowing could promote the invasion of Spartina alterniflora by increasing its competitive performance compared with native species. PMID:28348921

  6. Comparison of the diversity of root-associated bacteria in Phragmites australis and Typha angustifolia L. in artificial wetlands.

    PubMed

    Li, Yan Hong; Zhu, Jing Nan; Liu, Qun Fang; Liu, Yin; Liu, Min; Liu, Lei; Zhang, Qiang

    2013-08-01

    Common reed (Phragmites australis) and narrow-leaved cattail (Typha angustifolia L.) are two plant species used widely in artificial wetlands constructed to treat wastewater. In this study, the community structure and diversity of root-associated bacteria of common reed and narrow-leaved cattail growing in the Beijing Cuihu Wetland, China, were investigated using 16S rDNA library and PCR-denaturing gradient gel electrophoresis methods. Root-associated bacterial diversity was higher in common reed than in narrow-leaved cattail. In both plant species, the dominant root-associated bacterial species were Alpha, Beta and Gamma Proteobacteria, including the genera Aeromonas, Hydrogenophaga, Ideonella, Uliginosibacterium and Vogesella. Acidobacteria, Actinobacteria, Nitrospirae and Spirochaetes were only found in the roots of common reed. Comparing the root-associated bacterial communities of reed and cattail in our system, many more species of bacteria related involved in the total nitrogen cycle were observed in reed versus cattail, while species involved in total phosphorus and organic matter removal were mainly found in cattail. Although we cannot determine their nutrient removal capacity separately, differences in the root-associated bacterial communities may be an important factor contributing to the differing water purification effects mediated by T. angustifolia and P. australis wetlands. Thus, further work describing the ecosystem functions of these bacterial species is needed, in order to fully understand how effective common reed- and narrow-leaved cattail-dominated wetlands are for phytoremediation.

  7. Evapotranspiration from pilot-scale constructed wetlands planted with Phragmites australis in a Mediterranean environment.

    PubMed

    Milani, Mirco; Toscano, Attilio

    2013-01-01

    This article reports the results of evapotranspiration (ET) experiments carried out in Southern Italy (Sicily) in a pilot-scale constructed wetland (CW) made of a combination of vegetated (Phragmites australis) and unvegetated sub-surface flow beds. Domestic wastewater from a conventional wastewater treatment plant was used to fill the beds. Microclimate data was gathered from an automatic weather station close to the experimental plant. From June to November 2009 and from April to November 2010, ET values were measured as the amount of water needed to restore the initial volume in the beds after a certain period. Cumulative reference evapotranspiration (ET(0)) was similar to the cumulative ET measured in the beds without vegetation (ET(con)), while the Phragmites ET (ET (phr) ) was significantly higher underlining the effect of the vegetation. The plant coefficient of P. australis (K(p)) was very high (up to 8.5 in August 2009) compared to the typical K(c) for agricultural crops suggesting that the wetland environment was subjected to strong "clothesline" and "oasis" effects. According to the FAO 56 approach, K(p) shows different patterns and values in relation to growth stages correlating significantly to stem density, plant height and total leaves. The mean Water Use Efficiency (WUE) value of P. australis was quite low, about 2.27 g L(-1), probably due to the unlimited water availability and the lack of the plant's physiological adaptations to water conservation. The results provide useful and valid information for estimating ET rates in small-scale constructed wetlands since ET is a relevant issue in arid and semiarid regions. In these areas CW feasibility for wastewater treatment and reuse should also be carefully evaluated for macrophytes in relation to their WUE values.

  8. Is the invasion of the common reed, Phragmites australis, into tidal marshes of the eastern US an ecological disaster?

    PubMed

    Weis, Judith S; Weis, Peddrick

    2003-07-01

    Studies of effects of the invasive brackish marsh plant Phragmites australis (common reed) on estuarine biota are reviewed. With few exceptions, most field studies indicate that these P. australis-dominated marshes have diverse and abundant benthic biota, and are utilized by nekton, comparable to Spartina alterniflora marshes. However, larval mummichogs, Fundulus heteroclitus, appear to be reduced in P. australis marshes compared with S. alterniflora marshes. Small epifauna living on plant stems also appear to be denser on S. alterniflora than P. australis stems. Other studies indicate that the detritus produced by decaying P. australis litter provides food value comparable to that of S. alterniflora and that its production enters estuarine food webs. Therefore, the general assumption that these marshes are ecologically "useless" is untrue. This information should be considered by marsh managers when making decisions about restoration projects.

  9. Intraspecific N and P stoichiometry of Phragmites australis: geographic patterns and variation among climatic regions.

    PubMed

    Hu, Yu-Kun; Zhang, Ya-Lin; Liu, Guo-Fang; Pan, Xu; Yang, Xuejun; Li, Wen-Bing; Dai, Wen-Hong; Tang, Shuang-Li; Xiao, Tao; Chen, Ling-Yun; Xiong, Wei; Song, Yao-Bin; Dong, Ming

    2017-02-24

    Geographic patterns in leaf stoichiometry reflect plant adaptations to environments. Leaf stoichiometry variations along environmental gradients have been extensively studied among terrestrial plants, but little has been known about intraspecific leaf stoichiometry, especially for wetland plants. Here we analyzed the dataset of leaf N and P of a cosmopolitan wetland species, Phragmites australis, and environmental (geographic, climate and soil) variables from literature and field investigation in natural wetlands distributed in three climatic regions (subtropical, temperate and highland) across China. We found no clear geographic patterns in leaf nutrients of P. australis across China, except for leaf N:P ratio increasing with altitude. Leaf N and N:P decreased with mean annual temperature (MAT), and leaf N and P were closely related to soil pH, C:N ratio and available P. Redundancy analysis showed that climate and soil variables explained 62.1% of total variation in leaf N, P and N:P. Furthermore, leaf N in temperate region and leaf P in subtropical region increased with soil available P, while leaf N:P in subtropical region decreased with soil pH. These patterns in P. australis different from terrestrial plants might imply that changes in climate and soil properties can exert divergent effects on wetland and terrestrial ecosystems.

  10. Structure and biomechanics of culms of Phragmites australis used for reeds of Japanese wind instrument "hichiriki".

    PubMed

    Kawasaki, Masahiro; Nobuchi, Tadashi; Nakafushi, Yuta; Nose, Masateru; Shiojiri, Makoto

    2015-04-01

    Hichiriki is a traditional Japanese double-reed wind instrument used in Japanese ancient imperial court music, gagaku, which has been performed since the 7th century. The best reeds for hichiriki have been made of culms or stems of Phragmites australis (P. australis) that are harvested from only a limited reed bed at Udono near Kyoto. The aim of this study is to elucidate why the stems from Udono are the best materials for hichiriki reeds. Plant anatomy was examined for choice stems of P. australis grown in different reed beds in Japan as well as morphology, and the local indentation hardness and Young's modulus of tissues on the cross-sections of some representatives of hichiriki reeds were measured. It is concluded that the good stems for hichiriki reeds have an outer diameter of about 11 mm, a wall thickness of about 1 mm and comparatively homogeneous structure where harder materials, such as epidermis, hypodermis, sclerenchymatous cells, and vascular bundle sheaths with hard walls, are orderly deployed with softer materials such as parenchyma cells and vascular bundles. This structure has smaller differences of hardness and Young's modulus between the hard and soft materials in the reed, providing the best music performance.

  11. Intraspecific N and P stoichiometry of Phragmites australis: geographic patterns and variation among climatic regions

    PubMed Central

    Hu, Yu-Kun; Zhang, Ya-Lin; Liu, Guo-Fang; Pan, Xu; Yang, Xuejun; Li, Wen-Bing; Dai, Wen-Hong; Tang, Shuang-Li; Xiao, Tao; Chen, Ling-Yun; Xiong, Wei; Song, Yao-Bin; Dong, Ming

    2017-01-01

    Geographic patterns in leaf stoichiometry reflect plant adaptations to environments. Leaf stoichiometry variations along environmental gradients have been extensively studied among terrestrial plants, but little has been known about intraspecific leaf stoichiometry, especially for wetland plants. Here we analyzed the dataset of leaf N and P of a cosmopolitan wetland species, Phragmites australis, and environmental (geographic, climate and soil) variables from literature and field investigation in natural wetlands distributed in three climatic regions (subtropical, temperate and highland) across China. We found no clear geographic patterns in leaf nutrients of P. australis across China, except for leaf N:P ratio increasing with altitude. Leaf N and N:P decreased with mean annual temperature (MAT), and leaf N and P were closely related to soil pH, C:N ratio and available P. Redundancy analysis showed that climate and soil variables explained 62.1% of total variation in leaf N, P and N:P. Furthermore, leaf N in temperate region and leaf P in subtropical region increased with soil available P, while leaf N:P in subtropical region decreased with soil pH. These patterns in P. australis different from terrestrial plants might imply that changes in climate and soil properties can exert divergent effects on wetland and terrestrial ecosystems. PMID:28233774

  12. [Methane emission flux of Zhalong Phragmites australis wetlands in growth season].

    PubMed

    Huang, Pu-Yi; Yu, Hong-Xian; Chai, Long-Hui; Chai, Fang-Ying; Zhang, Wan-Feng

    2011-05-01

    Static chamber/gas chromatogram method was adopted to measure the methane emission flux of Zhalong Phragmites australis wetlands with different water levels in a growth season from May to October, 2009, aimed to understand the methane emission pattern in natural freshwater P. australis wetland in frigid region. During the observation period, the average methane emission flux of test wetlands ranged from -21.18 to 46.15 mg x m(-2) x h(-1), with a mean of 7.67 mg x m(-2) x h(-1). In deep water zone (average water level 100 cm) and shallow water zone (average water level 25 cm), the average methane emission flux was 5.81 and 9.52 mg x m(-2) x h(-1), with a peak in August and July, respectively, and the minimum in October. In summer (from June to July), the methane emission flux in deep water zone was significantly lower than that in shallow water zone; while in spring (May) and autumn (from August to October), a reversed trend was observed. The methane emission flux had a seasonal pattern of summer > autumn > spring, and a diurnal pattern of being the highest at 12:00 and 14:00 and the lowest at 0:00. Temperature and water level were the major factors affecting the methane emission flux in freshwater P. australis wetlands in frigid region.

  13. The effects of tannery wastewater on the development of different plant species and chromium accumulation in Phragmites australis.

    PubMed

    Calheiros, Cristina S C; Rangel, António O S S; Castro, Paula M L

    2008-10-01

    Toxicity tests were performed to assess the effect of tannery wastewater with different treatment levels on two wetland plants, Phragmites australis and Typha latifolia, which are frequently used in constructed wetlands (CWs) for water treatment, and thus deepen the knowledge on their capacity to withstand the application of industrial wastewater. Trifolium pratense, a plant generally used as an indicator in toxicity tests, was included as a control. End points measured were germination percentage, shoot length, root elongation, and biomass growth of the plants. When tannery effluent, with a low treatment level, was supplied to the wetland plants germination occurred even at effluent concentrations of 100%, whereas germination of T. pratense was completely inhibited, almost invariably, at effluent concentration of 50%. Higher germination levels were achieved when the plants were exposed to effluent originating from the outlet of constructed wetland pilot units, allowing germination of all tested plants, indicating a significant decrease in its toxicity level. Experiments conducted with the same plants using different growing substrata as the germination matrix, namely expanded clay aggregates (Filtralite MR 3-8 and Filtralite NR 3-8) and two types of sand (fine gravel and standard sand) have shown that higher germination levels were achieved in standard sand and that P. australis was the plant species showing higher germination in all cases, reinforcing the robustness of this plant to environmental stress. The phytoextraction potential of P. australis, was evaluated by subjecting the plant to tannery wastewater supplemented with 50 and 150 mg Cr/L. After 6 weeks of exposure, levels up to 4825, 883, and 627 mg Cr/kg were found in the rhizome, shoot, and leaves, respectively, although phytotoxic signs in the plant were evident. This plant might not be considered a chromium hyperacumulator, but the potential to extract and accumulate this metal on its rhizomes is high.

  14. Decomposition of Phragmites australis litter retarded by invasive Solidago canadensis in mixtures: an antagonistic non-additive effect.

    PubMed

    Zhang, Ling; Zhang, Yaojun; Zou, Jianwen; Siemann, Evan

    2014-06-30

    Solidago canadensis is an aggressive invader in China. Solidago invasion success is partially attributed to allelopathic compounds release and more benefits from AM fungi, which potentially makes the properties of Solidago litter different from co-occurring natives. These properties may comprehensively affect litter decomposition of co-occurring natives. We conducted a field experiment to examine litter mixing effects in a Phragmites australis dominated community invaded by Solidago in southeast China. Solidago had more rapid mass and N loss rate than Phragmites when they decomposed separately. Litter mixing decreased N loss rate in Phragmites litter and increased that of Solidago. Large decreases in Phragmites mass loss and smaller increases in Solidago mass loss caused negative non-additive effect. Solidago litter extracts reduced soil C decomposition and N processes, suggested an inhibitory effect of Solidago secondary compounds. These results are consistent with the idea that nutrient transfer and secondary compounds both affected litter mixtures decomposition.

  15. Decomposition of Phragmites australis litter retarded by invasive Solidago canadensis in mixtures: an antagonistic non-additive effect

    NASA Astrophysics Data System (ADS)

    Zhang, Ling; Zhang, Yaojun; Zou, Jianwen; Siemann, Evan

    2014-06-01

    Solidago canadensis is an aggressive invader in China. Solidago invasion success is partially attributed to allelopathic compounds release and more benefits from AM fungi, which potentially makes the properties of Solidago litter different from co-occurring natives. These properties may comprehensively affect litter decomposition of co-occurring natives. We conducted a field experiment to examine litter mixing effects in a Phragmites australis dominated community invaded by Solidago in southeast China. Solidago had more rapid mass and N loss rate than Phragmites when they decomposed separately. Litter mixing decreased N loss rate in Phragmites litter and increased that of Solidago. Large decreases in Phragmites mass loss and smaller increases in Solidago mass loss caused negative non-additive effect. Solidago litter extracts reduced soil C decomposition and N processes, suggested an inhibitory effect of Solidago secondary compounds. These results are consistent with the idea that nutrient transfer and secondary compounds both affected litter mixtures decomposition.

  16. Using Transcriptomics to Identify Differential Gene Expression in Response to Salinity among Australian Phragmites australis Clones

    PubMed Central

    Holmes, Gareth D.; Hall, Nathan E.; Gendall, Anthony R.; Boon, Paul I.; James, Elizabeth A.

    2016-01-01

    Common Reed (Phragmites australis) is a frequent component of inland and coastal wetlands in temperate zones worldwide. Ongoing environmental changes have resulted in the decline of this species in many areas and invasive expansion in others. In the Gippsland Lakes coastal waterway system in south-eastern Australia, increasing salinity is thought to have contributed to the loss of fringing P. australis reed beds leading to increased shoreline erosion. A major goal of restoration in this waterway is to address the effect of salinity by planting a genetically diverse range of salt-tolerant P. australis plants. This has prompted an interest in examining the variation in salinity tolerance among clones and the underlying basis of this variation. Transcriptomics is an approach for identifying variation in genes and their expression levels associated with the exposure of plants to environmental stressors. In this paper we present initial results of the first comparative culm transcriptome analysis of P. australis clones. After sampling plants from sites of varied surface water salinity across the Gippsland Lakes, replicates from three clones from highly saline sites (>18 g L-1 TDS) and three from low salinity sites (<6 g L-1) were grown in containers irrigated with either fresh (<0.1 g L-1) or saline water (16 g L-1). An RNA-Seq protocol was used to generate sequence data from culm tissues from the 12 samples allowing an analysis of differential gene expression. Among the key findings, we identified several genes uniquely up- or down-regulated in clones from highly saline sites when irrigated with saline water relative to clones from low salinity sites. These included the higher relative expression levels of genes associated with photosynthesis and lignan biosynthesis indicative of a greater ability of these clones to maintain growth under saline conditions. Combined with growth data from a parallel study, our data suggests local adaptation of certain clones to salinity

  17. Using Transcriptomics to Identify Differential Gene Expression in Response to Salinity among Australian Phragmites australis Clones.

    PubMed

    Holmes, Gareth D; Hall, Nathan E; Gendall, Anthony R; Boon, Paul I; James, Elizabeth A

    2016-01-01

    Common Reed (Phragmites australis) is a frequent component of inland and coastal wetlands in temperate zones worldwide. Ongoing environmental changes have resulted in the decline of this species in many areas and invasive expansion in others. In the Gippsland Lakes coastal waterway system in south-eastern Australia, increasing salinity is thought to have contributed to the loss of fringing P. australis reed beds leading to increased shoreline erosion. A major goal of restoration in this waterway is to address the effect of salinity by planting a genetically diverse range of salt-tolerant P. australis plants. This has prompted an interest in examining the variation in salinity tolerance among clones and the underlying basis of this variation. Transcriptomics is an approach for identifying variation in genes and their expression levels associated with the exposure of plants to environmental stressors. In this paper we present initial results of the first comparative culm transcriptome analysis of P. australis clones. After sampling plants from sites of varied surface water salinity across the Gippsland Lakes, replicates from three clones from highly saline sites (>18 g L(-1) TDS) and three from low salinity sites (<6 g L(-1)) were grown in containers irrigated with either fresh (<0.1 g L(-1)) or saline water (16 g L(-1)). An RNA-Seq protocol was used to generate sequence data from culm tissues from the 12 samples allowing an analysis of differential gene expression. Among the key findings, we identified several genes uniquely up- or down-regulated in clones from highly saline sites when irrigated with saline water relative to clones from low salinity sites. These included the higher relative expression levels of genes associated with photosynthesis and lignan biosynthesis indicative of a greater ability of these clones to maintain growth under saline conditions. Combined with growth data from a parallel study, our data suggests local adaptation of certain clones to

  18. Bioaccumulation of selected metals in bivalves (Unionidae) and Phragmites australis inhabiting a municipal water reservoir.

    PubMed

    Rzymski, Piotr; Niedzielski, Przemysław; Klimaszyk, Piotr; Poniedziałek, Barbara

    2014-05-01

    Urbanization can considerably affect water reservoirs by, inter alia, input, and accumulation of contaminants including metals. Located in the course of River Cybina, Maltański Reservoir (Western Poland) is an artificial shallow water body built for recreation and sport purposes which undergoes restoration treatment (drainage) every 4 years. In the present study, we demonstrate an accumulation of nine metals (Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, Zn) in water, sediment, three bivalve species (Anodonta anatina, Anodonta cygnea, Unio tumidus), and macrophyte Phragmites australis collected before complete drainage in November 2012. The mean concentrations of metals in the sediment, bivalves, and P. australis (roots and leaves) decreased in the following order: Fe > Mn > Zn > Cu > Cr > Ni > Pb > Co > Cd. A considerably higher bioconcentration of metals was observed in samples collected from the western and southern sites which undergo a higher degree of human impact. Sediments were found to be a better indicator of metal contamination than water samples. Interspecific differences in levels of metal accumulation were found between investigated unionids. U. tumidus accumulated higher levels of Cr, positively correlated with ambient concentrations, predisposing this species as a potential bioindicator of this metal in aquatic environments. On the other hand, species of Anodonta genus demonstrated higher accumulation of Cu and Cd. Positive correlations were found between Pb content in the sediments and tissues of all three bivalve species. In P. australis, metals were largely retained in roots except for Cd and Pb for which higher concentrations were found in leaves suggesting additional absorption of these metals from aerial sources. P. australis and bivalve from the Maltański Reservoir may be a potential source of toxic metals for animals feeding upon them and contribute to further contamination in the food chain.

  19. Salt tolerance underlies the cryptic invasion of North American salt marshes by an introduced haplotype of the common reed Phragmites australis (Poaceae)

    USGS Publications Warehouse

    Vasquez, Edward A.; Glenn, Edward P.; Brown, J. Jed; Guntenspergen, Glenn R.; Nelson, Stephen G.

    2005-01-01

    A distinct, non-native haplotype of the common reed Phragmites australis has become invasive in Atlantic coastal Spartina marshes. We compared the salt tolerance and other growth characteristics of the invasive M haplotype with 2 native haplotypes (F and AC) in greenhouse experiments. The M haplotype retained 50% of its growth potential up to 0.4 M NaCl, whereas the F and AC haplotypes did not grow above 0.1 M NaCl. The M haplotype produced more shoots per gram of rhizome tissue and had higher relative growth rates than the native haplotypes on both freshwater and saline water treatments. The M haplotype also differed from the native haplotypes in shoot water content and the biometrics of shoots and rhizomes. The results offer an explanation for how the M haplotype is able to spread in coastal salt marshes and support the conclusion of DNA analyses that the M haplotype is a distinct ecotype of P. australis.

  20. Mapping invasive Phragmites australis in the coastal Great Lakes with ALOS PALSAR satellite imagery for decision support

    USGS Publications Warehouse

    Bourgeau-Chavez, Laura L.; Kowalski, Kurt P.; Carlson Mazur, Martha L.; Scarbrough, Kirk A.; Powell, Richard B.; Brooks, Colin N.; Huberty, Brian; Jenkins, Liza K.; Banda, Elizabeth C.; Galbraith, David M.; Laubach, Zachary M.; Riordan, Kevin

    2013-01-01

    The invasive variety of Phragmites australis (common reed) forms dense stands that can cause negative impacts on coastal Great Lakes wetlands including habitat degradation and reduced biological diversity. Early treatment is key to controlling Phragmites, therefore a map of the current distribution is needed. ALOS PALSAR imagery was used to produce the first basin-wide distribution map showing the extent of large, dense invasive Phragmites-dominated habitats in wetlands and other coastal ecosystems along the U.S. shore of the Great Lakes. PALSAR is a satellite imaging radar sensor that is sensitive to differences in plant biomass and inundation patterns, allowing for the detection and delineation of these tall (up to 5 m), high density, high biomass invasive Phragmites stands. Classification was based on multi-season ALOS PALSAR L-band (23 cm wavelength) HH and HV polarization data. Seasonal (spring, summer, and fall) datasets were used to improve discrimination of Phragmites by taking advantage of phenological changes in vegetation and inundation patterns over the seasons. Extensive field collections of training and randomly selected validation data were conducted in 2010–2011 to aid in mapping and for accuracy assessments. Overall basin-wide map accuracy was 87%, with 86% producer's accuracy and 43% user's accuracy for invasive Phragmites. The invasive Phragmites maps are being used to identify major environmental drivers of this invader's distribution, to assess areas vulnerable to new invasion, and to provide information to regional stakeholders through a decision support tool.

  1. Diversity of fungal endophytes in non-native Phragmites australis in the Great Lakes

    USGS Publications Warehouse

    Clay, Keith; Shearin, Zachery; Bourke, Kimberly; Bickford, Wesley A.; Kowalski, Kurt P.

    2016-01-01

    Plant–microbial interactions may play a key role in plant invasions. One common microbial interaction takes place between plants and fungal endophytes when fungi asymptomatically colonize host plant tissues. The objectives of this study were to isolate and sequence fungal endophytes colonizing non-native Phragmites australis in the Great Lakes region to evaluate variation in endophyte community composition among three host tissue types and three geographical regions. We collected entire ramets from multiple clones and populations, surface sterilized plant tissues, and plated replicate tissue samples from leaves, stems, and rhizomes on corn meal agar plates to culture and isolate fungal endophytes. Isolates were then subjected to Sanger sequencing of the ITS region of the nuclear ribosomal DNA. Sequences were compared to fungal databases to define operational taxonomic units (OTUs) that were analyzed statistically for community composition. In total, we obtained 173 endophyte isolates corresponding to 55 OTUs, 39 of which were isolated only a single time. The most common OTU corresponded most closely to Sarocladium strictum and comprised 25 % of all fungal isolates. More OTUs were found in stem tissues, but endophyte diversity was greatest in rhizome tissues. PERMANOVA analyses indicated significant differences in endophyte communities among tissue types, geographical regions, and the interaction between those factors, but no differences among individual ramets were detected. The functional role of the isolated endophytes is not yet known, but one genus isolated here (Stagonospora) has been reported to enhance Phragmites growth. Understanding the diversity and functions of Phragmites endophytes may provide targets for control measures based on disrupting host plant/endophyte interactions.

  2. Short term uptake and transport process for metformin in roots of Phragmites australis and Typha latifolia.

    PubMed

    Cui, H; Hense, B A; Müller, J; Schröder, P

    2015-09-01

    Metformin (MET) as an emerging contaminant has been detected in surface water and wastewater in numerous countries, due to insufficient retention in classical waste water treatment plants. In order to characterize the uptake of the compound during phytotreatment of waste water, a short term Pitman chamber experiment was carried out to assess the characteristics of MET uptake and transport by roots. Three different concentrations (0.5, 1.0 and 2.0 mmol L(-)(1)) were applied to cattail (Typha latifolia) and reed (Phragmites australis) roots which were used to investigate the uptake mechanism because they are frequently utilized in phytoremediation. In addition, quinidine was used as an inhibitor to assess the role of organic cation transporters (OCTs) in the uptake of MET by T. latifolia. The transport process of MET is different from carbamazepine (CBZ) and caffeine (CFN). In both T. latifolia and P. australis, the uptake processes were independent of initial concentrations. Quinidine, a known inhibitor of organic cation transporters, can significantly affect MET uptake by T. latifolia roots with inhibition ratios of 70-74%. Uptake into the root could be characterized by a linear model with R(2) values in the range of 0.881-0.999. Overall, the present study provides evidence that MET is taken up by plant roots and has the potential for subsequent translocation. OCTs could be one of the important pathways for MET uptake into the plant.

  3. Phosphate and ammonium adsorption of the modified biochar based on Phragmites australis after phytoremediation.

    PubMed

    Gong, Yu-Peng; Ni, Zhi-Yi; Xiong, Zhao-Zhao; Cheng, Li-Hua; Xu, Xin-Hua

    2017-02-04

    To effectively remove N and P from eutrophic water, the Phragmites australis after phytoremediation was harvested for preparation of modified biochar. The MgCl2-modified biochar (MPB) was successfully synthesized at 600 °C under N2 circumstance. The physiochemical characteristics, the adsorption capacity for N and P in the simulated solution, and their adsorption mechanism of MPB were then determined, followed by the treatment of eutrophic water of Tai lake and its inflow river from agricultural source. The results demonstrated that the MPB presented high adsorption capacity to both simulated NH4-N and PO4-P with the maximum adsorption capacity exceeding 30 and 100 mg g(-1), respectively. The entire ammonium adsorption process could be described by a pseudo-second-order kinetic model whereas the phosphate adsorption process could be divided into three phases, as described by both intra-particle diffusion model and the pseudo-first-order kinetic. It was further found that the dominant mechanism for ammonium adsorption was Mg(2+) exchange instead of functional groups and surface areas and the Mg-P precipitation was the main mechanism for phosphate adsorption. The MPB also showed high removal ratio of practical TP which reached nearly 90% for both the water in Tai lake and its agricultural source. It suggested that MPB based on harvested P. australis was a promising composite for eutrophic water treatment and it could deliver multiple benefits. Graphic abstract.

  4. Zinc isotopic fractionation in Phragmites australis in response to toxic levels of zinc

    PubMed Central

    Caldelas, Cristina; Dong, Shuofei; Araus, José Luis; Jakob Weiss, Dominik

    2011-01-01

    Stable isotope signatures of Zn have shown great promise in elucidating changes in uptake and translocation mechanisms of this metal in plants during environmental changes. Here this potential was tested by investigating the effect of high Zn concentrations on the isotopic fractionation patterns of Phragmites australis (Cav.) Trin. ex Steud. Plants were grown for 40 d in a nutritive solution containing 3.2 μM (sufficient) or 2 mM (toxic) Zn. The Zn isotopic composition of roots, rhizomes, shoots, and leaves was analysed. Stems and leaves were sampled at different heights to evaluate the effect of long-distance transport on Zn fractionation. During Zn sufficiency, roots, rhizomes, and shoots were isotopically heavy (δ66ZnJMC Lyon=0.2‰) while the youngest leaves were isotopically light (–0.5‰). During Zn excess, roots were still isotopically heavier (δ66Zn=0.5‰) and the rest of the plant was isotopically light (up to –0.5‰). The enrichment of heavy isotopes at the roots was attributed to Zn uptake mediated by transporter proteins under Zn-sufficient conditions and to chelation and compartmentation in Zn excess. The isotopically lighter Zn in shoots and leaves is consistent with long-distance root to shoot transport. The tolerance response of P. australis increased the range of Zn fractionation within the plant and with respect to the environment. PMID:21193582

  5. Vegetation persistence and carbon storage: Implications for environmental water management for Phragmites australis

    NASA Astrophysics Data System (ADS)

    Whitaker, Kai; Rogers, Kerrylee; Saintilan, Neil; Mazumder, Debashish; Wen, Li; Morrison, R. J.

    2015-07-01

    Environmental water allocations are used to improve the ecological health of wetlands. There is now increasing demand for allocations to improve ecosystem productivity and respiration, and enhance carbon sequestration. Despite global recognition of wetlands as carbon sinks, information regarding carbon dynamics is lacking. This is the first study estimating carbon sequestration for semiarid Phragmites australis reedbeds. The study combined aboveground biomass assessments with stable isotope analyses of soils and modeling of biomass using Normalized Digital Vegetation Index (NDVI) to investigate the capacity of environmental water allocations to improve carbon storage. The study considered relationships between soil organic carbon (SOC), carbon sources, and reedbed persistence in the Macquarie Marshes, a regulated semiarid floodplain of the Murray-Darling Basin, Australia. SOC storage levels to 1 m soil depth were higher in persistent reedbeds (167 Mg ha-1) than ephemeral reedbeds (116-138 Mg ha-1). In situ P. australis was the predominant source of surface SOC at persistent reedbeds; mixed sources of surface SOC were proposed for ephemeral reedbeds. 13C enrichment with increasing soil depth occurred in persistent and ephemeral reedbeds and may not relate to flow characteristics. Despite high SOC at persistent reedbeds, differences in the rate of accretion contributed to significantly higher rates of carbon sequestration at ephemeral reedbeds (approximately 554 and 465 g m-2 yr-1) compared to persistent reedbeds (5.17 g m-2 yr-1). However, under current water regimes, rapid accretion at ephemeral reedbeds cannot be maintained. Effective management of persistent P. australis reedbeds may enhance carbon sequestration in the Macquarie Marshes and floodplain wetlands more generally.

  6. A Comparison of the Functional Traits of Common Reed (Phragmites australis) in Northern China: Aquatic vs. Terrestrial Ecotypes

    PubMed Central

    Li, Liping; Han, Wenxuan; Thevs, Niels; Jia, Xiuhong; Ji, Chengjun; Jin, Dongmei; He, Ping; Schmitt, Armin O.; Cirella, Giuseppe Tommaso; Zerbe, Stefan

    2014-01-01

    Common reed (Phragmites australis (Cav.) Trin. ex Steud.) is distributed widely throughout the world with various ecotypes. This research compares the functional traits and biomass allocation patterns of two contrasting reed ecotypes. Twelve pairs of aquatic and terrestrial reed samples were collected in northern China. Significant differences in functional traits between the two reed ecotypes were observed, while biomass allocation patterns of reed organs did not differ significantly except for at the root. The dry matter content (DMC) in the whole of the reed plant, leaf, root, and rhizome was higher; while the specific leaf area (SLA) and specific root length (SRL) were lower in terrestrial versus aquatic reed. The biomass allocation in organs of the two forms of reed was isometric, only root in the terrestrial habitat increased faster with an increase in the whole plant biomass. It can be affirmed that aquatic and terrestrial reed that adapt to different environments generally has distinct leaf and root functional traits but isometric biomass allocation patterns. This suggests different resource acquisition strategies: (1) aquatic reed grows faster with high SLA and SRL and is more responsive to the environment, while (2) terrestrial reed with high DMC grows slower and is less responsive to the adverse environment (e.g. dry soil conditions). PMID:24586505

  7. Synchrotron X-ray microfluorescence measurement of metal distributions in Phragmites australis root system in the Yangtze River intertidal zone.

    PubMed

    Feng, Huan; Zhang, Weiguo; Qian, Yu; Liu, Wenliang; Yu, Lizhong; Yoo, Shinjae; Wang, Jun; Wang, Jia Jun; Eng, Christopher; Liu, Chang Jun; Tappero, Ryan

    2016-07-01

    This study investigates the distributions of Br, Ca, Cl, Cr, Cu, K, Fe, Mn, Pb, Ti, V and Zn in Phragmites australis root system and the function of Fe nanoparticles in scavenging metals in the root epidermis using synchrotron X-ray microfluorescence, synchrotron transmission X-ray microscope measurement and synchrotron X-ray absorption near-edge structure techniques. The purpose of this study is to understand the mobility of metals in wetland plant root systems after their uptake from rhizosphere soils. Phragmites australis samples were collected in the Yangtze River intertidal zone in July 2013. The results indicate that Fe nanoparticles are present in the root epidermis and that other metals correlate significantly with Fe, suggesting that Fe nanoparticles play an important role in metal scavenging in the epidermis.

  8. Synchrotron X-ray microfluorescence measurement of metal distributions in Phragmites australis root system in the Yangtze River intertidal zone

    DOE PAGES

    Feng, Huan; Zhang, Weiguo; Qian, Yu; ...

    2016-06-15

    This paper investigates the distributions of Br, Ca, Cl, Cr, Cu, K, Fe, Mn, Pb, Ti, V and Zn in Phragmites australis root system and the function of Fe nanoparticles in scavenging metals in the root epidermis using synchrotron X-ray microfluorescence, synchrotron transmission X-ray microscope measurement and synchrotron X-ray absorption near-edge structure techniques. The purpose of this study is to understand the mobility of metals in wetland plant root systems after their uptake from rhizosphere soils. Phragmites australis samples were collected in the Yangtze River intertidal zone in July 2013. The results indicate that Fe nanoparticles are present in themore » root epidermis and that other metals correlate significantly with Fe, suggesting that Fe nanoparticles play an important role in metal scavenging in the epidermis.« less

  9. Dissolved inorganic nitrogen pools and surface flux under different brackish marsh vegetation types, common reed (Phragmites australis) and salt hay (Spartina patens)

    USGS Publications Warehouse

    Windham-Myers, L.

    2005-01-01

    The current expansion of Phragmites australis into the high marsh shortgrass (Spartina patens, Distichlis spicata) communities of eastern U.S. salt marshes provided an opportunity to identify the influence of vegetation types on pools and fluxes of dissolved inorganic nitrogen (DIN). Two brackish tidal marshes of the National Estuarine Research Reserve system were examined, Piermont Marsh of the Hudson River NERR in New York and Hog Island in the Jacques Coustaeu NERR of New Jersey. Pools of DIN in porewater and rates of DIN surface flux were compared in replicated pairs of recently-expanded P. australis and neighboring S. patens-dominated patches on the high marsh surface. Both marshes generally imported nitrate (NO3-) and exported ammonium (NH4+), such that overall DIN was exported. No differences in surface exchange of NO3- or NH4+ were observed between vegetation types. Depth-averaged porewater NH4+ concentrations over the entire growing season were 56% lower under P. australis than under S. patens (average 1.4 vs. 3.2 mg NH4+ L-1) with the most profound differences in November. Porewater profiles showed an accumulation of NH4+ at depth in S. patens and constant low concentrations in P. australis from the soil surface to 50 cm depth, with no significant differences in porewater salinity. Despite these profound differences in porewater, NH 4+ diffusion from soils of P. australis and S. patens were not measurably different, were similar to other published rates, and were well below estimated rates based on passive diffusion alone. Rapid adsorption and uptake by litter and microbes in surface soils of both communities may buffer NH4+ loss to flooding tides in both communities, thereby reducing the impact of P. australis invasion on NH4+ flux to flooding waters. ?? Springer 2005.

  10. An integrated modeling approach for monitoring and predicting common reed (Phragmites australis) colonization in a managed South Carolina estuary

    NASA Astrophysics Data System (ADS)

    Walker, Samuel Peter

    Recently, research efforts have focused on the development and testing of geographic information processing (GIP) techniques to more effectively identify and monitor invasive plant species in coastal ecosystems. While these efforts are progressing, particularly with refinements in hyperspectral image processing, there remains a lack of practical, science-based tools for decision-making with respect to the monitoring and mitigation of invasive plant species. Therefore, a geographic information systems (GIS) model is proposed to quantify the probability of a future exotic plant invasion in a user-defined area of interest. The primary objective of this investigation is to present conceptual and technical descriptions of a proposed modeling approach for prediction of common reed (Phragmites australis) colonization in a managed coastal wetland environment. Successful validation and adoption of the model will promote continued discourse regarding the impact of invasive species in coastal ecosystems, while providing the management community with a valuable decision support tool. Three main chapters comprise this manuscript; Chapter 1 focuses on the evaluation of remote sensing data and techniques for directly identifying Phragmites australis in a coastal ecosystem; Chapter 2 describes proposed, GIS-based models for predicting Phragmites colonization and future growth projections; and Chapter 3 discusses the results of the compiled relative suitability index (RSI) compilation and growth models, and considers the key management implications of the investigation. In the absence of a universal eradication solution for the invasive species Phragmites australis, an integrated management approach that utilizes a suite of dynamic, geo-spatial techniques in concert with more traditional practices is ultimately recommended. Keywords. Invasive species, estuary, NERRS, Phragmites, GIS-based models, remote sensing, coastal resource management, geographic information processing.

  11. Pressure gradients along whole culms and leaf sheaths, and other aspects of humidity-induced gas transport in Phragmites australis.

    PubMed

    Afreen, F; Zobayed, S M A; Armstrong, J; Armstrong, W

    2007-01-01

    Emergent aquatic macrophytes growing in waterlogged anaerobic sediments overlain by deep water require particularly efficient ventilating systems. In Phragmites australis (Cav.) Trin. ex Steud, pressurized gas flows, generated by humidity-induced diffusion of air into leaf sheaths, enhance oxygen transport to below-ground parts and aid in the removal of respiratory CO2 and sediment-generated CO2 and methane. Although modelling and flow measurements have pointed to the probable involvement of all leaf sheaths in the flow process and the development of pressure gradients along the whole lengths of living culm and leaf sheaths, direct measurements of pressure gradients have never been reported. The aim of this study was to search for pressure gradient development in Phragmites culms and leaf sheaths and to determine their magnitudes and distribution. In addition, dynamic (with gas flow) and static pressures (no flow condition) and their relationship to flows, leaf sheath areas, and living-to-dead culm ratios were further investigated. Dynamic pressures (DeltaPd) recorded in the pith cavities of intact (non-excised) leafy culms, pneumatically isolated from the below-ground parts and venting through an artificial bore-hole near the base, revealed a curvilinear gradient of pressure 'asymptoting' towards the tips of the culms. Similarly, DeltaPd in upper and lower parts of leaf sheaths increased with distance from the base of the culm, with values in the upper parts always being greater. Curvilinear gradients of pressure were also found along pneumatically isolated individual leaf sheaths, but radial channels linking the leaf sheath aerenchyma with the pith cavity of the culm appeared to offer little resistance to flow. In keeping with predictions, static pressure differentials (DeltaPs) achieved in intact and excised culms and single leaf sheaths on intact culms proved to be relatively independent of leaf sheath area, whereas the potential for developing convective flows

  12. [Effects of water table manipulation on leaf photosynthesis, morphology and growth of Phragmites australis and Imperata cylindrica in the reclaimed tidal wetland at Dongtan of Chongming Island, China].

    PubMed

    Zhong, Qi-Cheng; Wang, Jiang-Tao; Zhou, Jian-Hong; Ou, Qiang; Wang, Kai-Yun

    2014-02-01

    During the growing season of 2011, the leaf photosynthesis, morphological and growth traits of Phragmites australis and Imperata cylindrica were investigated along a gradient of water table (low, medium and high) in the reclaimed tidal wetland at the Dongtan of Chongming Island in the Yangtze Estuary of China. A series of soil factors, i. e., soil temperature, moisture, salinity and inorganic nitrogen content, were also measured. During the peak growing season, leaf photosynthetic capacity of P. australis in the wetland with high water table was significantly lower than those in the wetland with low and medium water tables, and no difference was observed in leaf photosynthetic capacity of I. cylindrica at the three water tables. During the entire growing season, at the shoot level, the morphological and growth traits of P. australis got the optimum in the wetland with medium water table, but most of the morphological and growth traits of I. cylindrica had no significant differences at the three water tables. At the population level, the shoot density, leaf area index and aboveground biomass per unit area were the highest in the wetland with high water table for P. australis, but all of the three traits were the highest in the wetland with low water table for I. cylindrica. At the early growing season, the rhizome biomass of P. australis in the 0-20 cm soil layer had no difference at the three water tables, and the rhizome biomass of I. cylindrica in the 0-20 cm soil layer in the wetland with high water table was significantly lower than those in the wetland with low and medium water table. As a native hygrophyte before the reclamation, the variations of performances of P. australis at the three water tables were probably attributed to the differences in the soil factors as well as the intensity of competition from I. cylindrica. To appropriately manipulate water table in the reclaimed tidal wetland may restrict the growth and propagation of the mesophyte I

  13. CO2 and CH4 exchange by Phragmites australis under different climates

    NASA Astrophysics Data System (ADS)

    Serrano Ortiz, Penélope; Chojnickic, Bogdan H.; Sánchez-Cañete, Enrique P.; Kowalska, Natalia; López-Ballesteros, Ana; Fernández, Néstor; Urbaniak, Marek; Olejnik, Janusz; Kowalski, Andrew S.

    2015-04-01

    The key role of wetlands regarding global warming is the resulting balance between net CO2 assimilation, via photosynthesis, and CO2 and CH4 emissions, given the potential to release stored carbon, because of the high temperature sensitivity of heterotrophic soil respiration and anoxic conditions. However, it is still unknown whether wetlands will convert from long-term carbon sinks to sources as a result of climate change and other anthropogenic effects such as land use changes. Phragmites australis is one of the most common species found in wetlands and is considered the most globally widespread and productive plant species in this type of ecosystem. In this context, the main objective of this study is to analyse the GHG exchange (CO2 and CH4) of two wetlands with Phragmites australis as the dominant species under different climates using the eddy covariance (EC) technique. The first site, Padul, is located in southern Spain, with a sub-humid warm climate, characterised by a mean annual temperature of 16°C and annual precipitation of ca. 470 mm, with a very dry summer. The second site, Rzecin is located in Poland with a mean annual temperature of 8°C, and annual precipitation around 600mm with no dry season. The Padul EC station is equipped with two infrared gas analysers to measure CO2 and CH4 fluxes (LI-7200 and LI-7700 respectively) while the Rzecin EC station has the same CH4 sensor as Padul, but also a sensor measuring both GHG fluxes (DLT-100 Fast Methane Analyser, Los Gatos). In this study, we present: i) the results of a CH4 analyser inter-comparison campaign (LI-7700 vs. Los Gatos), ii) a comparative analysis of the functional behaviour of respiration and photosynthesis in both sites testing relationships between CO2 fluxes measured with the EC technique and meteorological variables such as temperature and direct or diffuse radiation and iii) the CH4 dynamicsat both sites by identifying, when possible, annual, seasonal and diurnal patterns.

  14. Macroinvertebrates communities associated with the decomposition of Phragmites australis and Fucus vesiculosus in transitional systems

    NASA Astrophysics Data System (ADS)

    Lopes, Marta Lobão; Martins, Patrícia; Rodrigues, Ana Maria; Quintino, Victor

    2013-10-01

    The decomposition rates of a macrophyte (Phragmites australis) and an alga (Fucus vesiculosus) and the associated macrofauna communities were studied along a full salinity gradient, using the leaf-bag technique and four sampling times (days 3, 7, 15 and 30). A control was set up using an artificial substrate. A subsequent study conducted in the mesohaline part of the salinity gradient also included empty bags as procedure control. The decay rates of the alga and the macrophyte were significantly different, the alga decaying faster, and presented an opposite trend along the salinity gradient, with the faster decay rate for reed in the less saline areas and for the alga in the euhaline part of the gradient. The fauna associated with the decaying and the artificial substrate showed equally well the benthic succession from the marine to the freshwater areas, in all sampling times. Arthropods were dominant in all substrates along the estuarine gradient and replaced by annelids in freshwater. No significant differences were found between the benthic communities associated with P. australis and F. vesiculosus, despite the strong differences in the decay rates, suggesting that these do not seem to be primarily related to the benthic colonizers. Although the organic substrates sustained a more abundant fauna, the benthic communities did not show significant differences between the organic and the artificial substrates, especially at the level of the species composition, suggesting that the macroinvertebrates may colonize both substrates to feed on the biofilm and/or to seek shelter. The strongly impoverished benthic community sampled by the empty bags reinforced this idea.

  15. Decomposition of Phragmites australis rhizomes in artificial land-water transitional zones (ALWTZs) and management implications

    NASA Astrophysics Data System (ADS)

    Han, Zhen; Cui, Baoshan; Zhang, Yongtao

    2015-09-01

    Rhizomes are essential organs for growth and expansion of Phragmites australis. They function as an important source of organic matter and as a nutrient source, especially in the artificial land-water transitional zones (ALWTZs) of shallow lakes. In this study, decomposition experiments on 1- to 6-year-old P. australis rhizomes were conducted in the ALWTZ of Lake Baiyangdian to evaluate the contribution of the rhizomes to organic matter accumulation and nutrient release. Mass loss and changes in nutrient content were measured after 3, 7, 15, 30, 60, 90, 120, and 180 days. The decomposition process was modeled with a composite exponential model. The Pearson correlation analysis was used to analyze the relationships between mass loss and litter quality factors. A multiple stepwise regression model was utilized to determine the dominant factors that affect mass loss. Results showed that the decomposition rates in water were significantly higher than those in soil for 1- to 6-year-old rhizomes. However, the sequence of decomposition rates was identical in both water and soil. Significant relationships between mass loss and litter quality factors were observed at a later stage, and P-related factors proved to have a more significant impact than N-related factors on mass loss. According to multiple stepwise models, the C/P ratio was found to be the dominant factor affecting the mass loss in water, and the C/N and C/P ratios were the main factors affecting the mass loss in soil. The combined effects of harvesting, ditch broadening, and control of water depth should be considered for lake administrators.

  16. Disease protection and allelopathic interactions of seed-transmitted endophytic pseudomonads of invasive reed grass (Phragmites australis)

    USGS Publications Warehouse

    White, James F.; Kingsley, Katheryn I; Kowalski, Kurt P.; Irizarry, Ivelisse; Micci, April; Soares, Marcos Antonio; Bergen, Marshall S.

    2017-01-01

    Background and aimsNon-native Phragmites australis (haplotype M) is an invasive grass that decreases biodiversity and produces dense stands. We hypothesized that seeds of Phragmites carry microbes that improve seedling growth, defend against pathogens and maximize capacity of seedlings to compete with other plants.MethodsWe isolated bacteria from seeds of Phragmites, then evaluated representatives for their capacities to become intracellular in root cells, and their effects on: 1.) germination rates and seedling growth, 2.) susceptibility to damping-off disease, and 3.) mortality and growth of competitor plant seedlings (dandelion (Taraxacum officionale F. H. Wigg) and curly dock (Rumex crispus L.)).ResultsTen strains (of 23 total) were identified and characterized; seven were identified as Pseudomonas spp. Strains Sandy LB4 (Pseudomonas fluorescens) and West 9 (Pseudomonas sp.) entered root meristems and became intracellular. These bacteria improved seed germination in Phragmites and increased seedling root branching in Poa annua. They increased plant growth and protected plants from damping off disease. Sandy LB4 increased mortality and reduced growth rates in seedlings of dandelion and curly dock.ConclusionsPhragmites plants associate with endophytes to increase growth and disease resistance, and release bacteria into the soil to create an environment that is favorable to their seedlings and less favorable to competitor plants.

  17. The Physical and Biochemical Alteration of the Platte River by Phragmites australis, an Invasive Species of Wetland Grass

    NASA Astrophysics Data System (ADS)

    Mohr, R. C.; Krueger, R.; Triplett, L.; Michal, T.; Kettenring, K. M.

    2014-12-01

    Invasive species can have a profound impact on the ecosystems to which they are introduced. Beginning in 2003, the Platte River, Nebraska, USA, was invaded by an aggressive species of wetland grass, Phragmites australis. The invasion by Phragmites, in combination with river flow reductions due to agricultural irrigation, has drastically altered the character and morphology of the river. Once a braided and largely unvegetated river, the Platte had become densely colonized with vegetation by 2010. We measured some physical and biochemical characteristics of Platte River sediments to infer how that vegetation has changed the system. Specifically, we measured particle size, which is an indicator of flow velocity, and biogenic silica (BSi), which is a critical source of silicon for some aquatic organisms. Sediment was collected from areas of the riverbed that are unvegetated, and from areas that are occupied by Phragmites or native vegetation. Particle size was measured using a laser diffractometer to determine how much fine particle deposition was occurring. Biogenic silica (BSi) concentrations were measured using timed NaOH digestions and inductively coupled plasma mass spectrometry (ICP-MS). Our results indicate that stands of Phragmites in the Platte River cause more deposition of finer silt-sized particles than other parts of the river that are unvegetated or are occupied by native vegetation. Also, Phragmites increased the sequestration of BSi in the river sediments. These changes to the Platte reverberate beyond the river itself; by sequestering silica in sediments, Phragmites could be diminishing the supply of silica to estuaries and coastal oceans. Hypothesizing that the silica content of the Platte's water had been reduced by the arrival of Phragmites, we measured dissolved (DSi) and biogenic silica (BSi) concentrations of Platte water using ICP-MS to compare to existing data from the 1990s.

  18. Factors affecting post-control reinvasion by seed of an invasive species, Phragmites australis, in the central Platte River, Nebraska.

    USGS Publications Warehouse

    Galatowitsch, Susan M.; Larson, Diane L.; Larson, Jennifer L.

    2016-01-01

    Invasive plants, such as Phragmites australis, can profoundly affect channel environments of large rivers by stabilizing sediments and altering water flows. Invasive plant removal is considered necessary where restoration of dynamic channels is needed to provide critical habitat for species of conservation concern. However, these programs are widely reported to be inefficient. Post-control reinvasion is frequent, suggesting increased attention is needed to prevent seed regeneration. To develop more effective responses to this invader in the Central Platte River (Nebraska, USA), we investigated several aspects of Phragmites seed ecology potentially linked to post-control reinvasion, in comparison to other common species: extent of viable seed production, importance of water transport, and regeneration responses to hydrology. We observed that although Phragmites seed does not mature until very late in the ice-free season, populations produce significant amounts of viable seed (>50 % of filled seed). Most seed transported via water in the Platte River are invasive perennial species, although Phragmites abundances are much lower than species such as Lythrum salicaria, Cyperus esculentus and Phalaris arundinacea. Seed regeneration of Phragmites varies greatly depending on hydrology, especially timing of water level changes. Flood events coinciding with the beginning of seedling emergence reduced establishment by as much as 59 % compared to flood events that occurred a few weeks later. Results of these investigations suggest that prevention of seed set (i.e., by removal of flowering culms) should be a priority in vegetation stands not being treated annually. After seeds are in the seedbank, preventing reinvasion using prescribed flooding has a low chance of success given that Phragmites can regenerate in a wide variety of hydrologic microsites.

  19. Evapotranspiration from subsurface horizontal flow wetlands planted with Phragmites australis in sub-tropical Australia.

    PubMed

    Headley, T R; Davison, L; Huett, D O; Müller, R

    2012-02-01

    The balance between evapotranspiration (ET) loss and rainfall ingress in treatment wetlands (TWs) can affect their suitability for certain applications. The aim of this paper was to investigate the water balance and seasonal dynamics in ET of subsurface horizontal flow (HF) TWs in a sub-tropical climate. Monthly water balances were compiled for four pilot-scale HF TWs receiving horticultural runoff over a two year period (Sep. 1999-Aug. 2001) on the sub-tropical east-coast of Australia. The mean annual wetland ET rate increased from 7.0 mm/day in the first year to 10.6 mm/day in the second, in response to the development of the reed (Phragmites australis) population. Consequently, the annual crop coefficients (ratio of wetland ET to pan evaporation) increased from 1.9 in the first year to 2.6 in the second. The mean monthly ET rates were generally greater and more variable than the Class-A pan evaporation rates, indicating that transpiration is an important contributor to ET in HF TWs. Evapotranspiration rates were generally highest in the summer and autumn months, and corresponded with the times of peak standing biomass of P. australis. It is likely that ET from the relatively small 1 m wide by 4 m long HF TWs was enhanced by advection through so-called "clothesline" and "oasis" effects, which contributed to the high crop coefficients. For the second year, when the reed population was well established, the annual net loss to the atmosphere (taking into account rainfall inputs) accounted for 6.1-9.6 % of the influent hydraulic load, which is considered negligible. However, the net loss is likely to be higher in arid regions with lower rainfall. The Water Use Efficiency (WUE) of the wetlands in the second year of operation was 1.3 g of above-ground biomass produced per kilogram of water consumed, which is low compared to agricultural crops. It is proposed that system level WUE provides a useful metric for selecting wetland plant species and TW design alternatives to

  20. Between- and within-population differences in Phragmites australis : 1. The effects of nutrients on seedling growth.

    PubMed

    Clevering, O A

    1999-12-01

    Phragmites australis (common reed) is a dominant clonal species in the interface between land and water in many European wetlands. Along the land-water gradient, strong consistently different selective forces might operate to give rise to genetic substructuring. I have investigated the occurrence of genetic substructuring in European P. australis populations. The present paper examines whether seedlings, from seeds collected at both ends of the land-water gradient, showed differences in response to nutrient supply. Under controlled conditions, the relative growth rate (RGR) in the exponential growth phase, and growth characters of 10-week old seedlings were assessed. Among populations, no differences in response to nutrient supply were found. Although total dry weight was not related to the geographic origin of the populations, northern/western compared to southern/eastern European populations (1) formed more but shorter shoots, (2) formed thinner but longer rhizomes, and (3) invested more dry matter in leaves at the expense of stems. It was concluded that these trait differences are likely to originate from differences in the length of the growing season in the native habitat. Within populations, 'water-side' seedlings had a higher RGR under sub-optimal while for 'land-side' seedlings this was under optimal nutrient conditions. Ten-week-old 'water-side' seedlings had a higher total dry weight than 'land-side' ones, irrespective of nutrient loading. Differences in growth could not clearly be related to differences in single biomass allocation and morphological traits. A discriminant analysis on these traits, however, revealed that 'water-side' seedlings showed higher plasticity in discriminant scores than 'land-side' seedlings in response to nutrient supply. Discriminant scores also pointed towards a subtle trade-off between height versus expansion growth of seedlings, from the water to landward side. In the Romanian population, this could be related to

  1. Freshwater wetlands: fertile grounds for the invasive Phragmites australis in a climate change context

    PubMed Central

    Tougas-Tellier, Marie-Andrée; Morin, Jean; Hatin, Daniel; Lavoie, Claude

    2015-01-01

    Climate change will likely affect flooding regimes, which have a large influence on the functioning of freshwater riparian wetlands. Low water levels predicted for several fluvial systems make wetlands especially vulnerable to the spread of invaders, such as the common reed (Phragmites australis), one of the most invasive species in North America. We developed a model to map the distribution of potential germination grounds of the common reed in freshwater wetlands of the St. Lawrence River (Québec, Canada) under current climate conditions and used this model to predict their future distribution under two climate change scenarios simulated for 2050. We gathered historical and recent (remote sensing) data on the distribution of common reed stands for model calibration and validation purposes, then determined the parameters controlling the species establishment by seed. A two-dimensional model and the identified parameters were used to simulate the current (2010) and future (2050) distribution of germination grounds. Common reed stands are not widespread along the St. Lawrence River (212 ha), but our model suggests that current climate conditions are already conducive to considerable further expansion (>16,000 ha). Climate change may also exacerbate the expansion, particularly if river water levels drop, which will expose large bare areas propitious to seed germination. This phenomenon may be particularly important in one sector of the river, where existing common reed stands could increase their areas by a factor of 100, potentially creating the most extensive reedbed complex in North America. After colonizing salt and brackishwater marshes, the common reed could considerably expand into the freshwater marshes of North America which cover several million hectares. The effects of common reed expansion on biodiversity are difficult to predict, but likely to be highly deleterious given the competitiveness of the invader and the biological richness of freshwater

  2. Freshwater wetlands: fertile grounds for the invasive Phragmites australis in a climate change context.

    PubMed

    Tougas-Tellier, Marie-Andrée; Morin, Jean; Hatin, Daniel; Lavoie, Claude

    2015-08-01

    Climate change will likely affect flooding regimes, which have a large influence on the functioning of freshwater riparian wetlands. Low water levels predicted for several fluvial systems make wetlands especially vulnerable to the spread of invaders, such as the common reed (Phragmites australis), one of the most invasive species in North America. We developed a model to map the distribution of potential germination grounds of the common reed in freshwater wetlands of the St. Lawrence River (Québec, Canada) under current climate conditions and used this model to predict their future distribution under two climate change scenarios simulated for 2050. We gathered historical and recent (remote sensing) data on the distribution of common reed stands for model calibration and validation purposes, then determined the parameters controlling the species establishment by seed. A two-dimensional model and the identified parameters were used to simulate the current (2010) and future (2050) distribution of germination grounds. Common reed stands are not widespread along the St. Lawrence River (212 ha), but our model suggests that current climate conditions are already conducive to considerable further expansion (>16,000 ha). Climate change may also exacerbate the expansion, particularly if river water levels drop, which will expose large bare areas propitious to seed germination. This phenomenon may be particularly important in one sector of the river, where existing common reed stands could increase their areas by a factor of 100, potentially creating the most extensive reedbed complex in North America. After colonizing salt and brackishwater marshes, the common reed could considerably expand into the freshwater marshes of North America which cover several million hectares. The effects of common reed expansion on biodiversity are difficult to predict, but likely to be highly deleterious given the competitiveness of the invader and the biological richness of freshwater

  3. Long-term (two annual cycles) phytoremediation of heavy metal-contaminated estuarine sediments by Phragmites australis.

    PubMed

    Cicero-Fernández, Diego; Peña-Fernández, Manuel; Expósito-Camargo, Jose A; Antizar-Ladislao, Blanca

    2016-07-20

    The long-term (i.e., two consecutive annual cycles) ability of Phragmites australis to remediate estuarine sediments contaminated with heavy metals (Co, Ni, Mo, Cd, Pb, Cr, Cu, Fe, Mn, Zn and Hg) and trace elements of concern (As, Se, Ba) was investigated using an experimental approach on a pilot plant scale. The accumulation of these elements on belowground and aboveground tissues was monitored during vegetative and senescence periods for two populations of P. australis, originally from contaminated (MIC) and non-contaminated (GAL) estuaries, respectively. The initial concentration of the elements in the contaminated estuarine sediment decreased in the following order: Fe>Mn>Zn>Pb>Ba>Cr>As>Cu>Ni>Co>Mo>Cd>Se>Hg. A similar trend was recorded in the belowground biomass following remediation, suggesting the potential role of P. australis as an effective biomonitoring tool. Hg was not detected in any plant tissue. An overall annual increase of concentration levels in belowground tissue was observed. Overall, this study suggested that P. australis populations from GAL were substantially more efficient in taking up Ni, Mo and Cr during the second annual cycle in both belowground and aboveground tissue than P. australis populations from MIC. Calculated bio-concentration factors (BCF) suggested a clear metal excluder strategy for Co, Cd, Pb, Cu and Fe, with accumulation and stabilisation belowground, with limited translocation into aerial tissues observed during the length of this study. An excluder behaviour for Zn, Ba and Mn was detected during the second annual cycle, coinciding with a substantial increase of concentration levels belowground. This study demonstrated for the first time the long term efficacy of P. australis for phytoremediation of heavy metal contaminated estuarine sediments.

  4. Phragmites australis + Typha latifolia Community Enhanced the Enrichment of Nitrogen and Phosphorus in the Soil of Qin Lake Wetland.

    PubMed

    Ge, Zhiwei; An, Ran; Fang, Shuiyuan; Lin, Pengpeng; Li, Chuan; Xue, Jianhui; Yu, Shuiqiang

    2017-01-01

    Aquatic plants play an essential role and are effective in mitigating lake eutrophication by forming complex plant-soil system and retaining total nitrogen (TN) and phosphorus (TP) in soils to ultimately reduce their quantities in aquatic systems. Two main vegetation types (Phragmites australis community and P. australis + Typha latifolia community) of Qin Lake wetland were sampled in this study for the analysis of TN and TP contents and reserves in the wetland soils. The results showed that (1) the consumption effect of Qin Lake wetland on soluble N was much more significant than on soluble P. (2) The efficiency of TN enrichment in wetland soil was enhanced by vegetation covering of P. australis and T. latifolia. (3) Wetland soil P was consumed by P. australis community and this pattern was relieved with the introduction of T. latifolia. (4) According to the grey relativity analysis, the most intensive interaction between plants and soil occurred in summer. In addition, the exchange of N in soil-vegetation system primarily occurred in the 0-15 cm soil layer. Our results indicated that vegetation covering was essential to the enrichment of TN and TP, referring to the biology-related fixation in the wetland soil.

  5. Phragmites australis + Typha latifolia Community Enhanced the Enrichment of Nitrogen and Phosphorus in the Soil of Qin Lake Wetland

    PubMed Central

    An, Ran; Fang, Shuiyuan; Lin, Pengpeng; Xue, Jianhui; Yu, Shuiqiang

    2017-01-01

    Aquatic plants play an essential role and are effective in mitigating lake eutrophication by forming complex plant-soil system and retaining total nitrogen (TN) and phosphorus (TP) in soils to ultimately reduce their quantities in aquatic systems. Two main vegetation types (Phragmites australis community and P. australis + Typha latifolia community) of Qin Lake wetland were sampled in this study for the analysis of TN and TP contents and reserves in the wetland soils. The results showed that (1) the consumption effect of Qin Lake wetland on soluble N was much more significant than on soluble P. (2) The efficiency of TN enrichment in wetland soil was enhanced by vegetation covering of P. australis and T. latifolia. (3) Wetland soil P was consumed by P. australis community and this pattern was relieved with the introduction of T. latifolia. (4) According to the grey relativity analysis, the most intensive interaction between plants and soil occurred in summer. In addition, the exchange of N in soil-vegetation system primarily occurred in the 0–15 cm soil layer. Our results indicated that vegetation covering was essential to the enrichment of TN and TP, referring to the biology-related fixation in the wetland soil. PMID:28299233

  6. Effects of planting Phragmites australis on nitrogen removal, microbial nitrogen cycling, and abundance of ammonia-oxidizing and denitrifying microorganisms in sediments.

    PubMed

    Toyama, Tadashi; Nishimura, Yoshiko; Ogata, Yuka; Sei, Kazunari; Mori, Kazuhiro; Ike, Michihiko

    2015-10-21

    We examined the effect of planting an emergent aquatic plant (Phragmites australis) on nitrogen removal from sediments using a 42-d pot experiment. The experimental pot systems comprised two types of sediments planted with and without young P. australis. Total nitrogen (total N), total dissolved N, and NH4-N in the sediments decreased markedly after planting. In contrast, those levels decreased only slightly in the unplanted sediments. The decrease in total N in the P. australis-planted sediments was 7-20 times those in the unplanted sediments. Abundances of bacterial 16S rRNA, archaeal 16S rRNA, ammonia-oxidizing bacterial ammonia monooxygenase (amoA), ammonia-oxidizing archaeal amoA, and denitrifying bacterial nitrite reductase (nirK) genes increased significantly in sediments after planting. Phragmites australis appears to have released oxygen and created a repeating cycle of oxidizing and reducing conditions in the sediments. These conditions should promote mineralization of organic N, nitrification, and denitrification in the sediments. Phragmites australis absorbed bioavailable nitrogen generated by microbial nitrogen metabolism. During the 42-d period after planting, 31-44% of total N was removed by microbial nitrogen cycling, and 56-69% was removed via absorption by P. australis. These results suggest that planting P. australis can increase microbial populations and their activities, and that nitrogen removal can be accelerated by the combined functions of P. australis and microorganisms in the sediment. Thus, planting P. australis has considerable potential as an effective remediation technology for eutrophic sediments.

  7. The role of Phragmites australis in mediating inland salt marsh migration in a Mid-Atlantic estuary.

    PubMed

    Smith, Joseph A M

    2013-01-01

    Many sea level rise adaptation plans emphasize the protection of adjacent uplands to allow for inland salt marsh migration, but little empirical information exists on this process. Using aerial photos from 1930 and 2006 of Delaware Estuary coastal habitats in New Jersey, I documented the rate of coastal forest retreat and the rate of inland salt marsh migration across 101.1 km of undeveloped salt marsh and forest ecotone. Over this time, the amount of forest edge at this ecotone nearly doubled. In addition, the average amount of forest retreat was 141.2 m while the amount of salt marsh inland migration was 41.9 m. Variation in forest retreat within the study area was influenced by variation in slope. The lag between the amount of forest retreat and salt marsh migration is accounted for by the presence of Phragmites australis which occupies the forest and salt marsh ecotone. Phragmites expands from this edge into forest dieback areas, and the ability of salt marsh to move inland and displace Phragmites is likely influenced by salinity at both an estuary-wide scale and at the scale of local subwatersheds. Inland movement of salt marsh is lowest at lower salinity areas further away from the mouth of the estuary and closer to local heads of tide. These results allow for better prediction of salt marsh migration in estuarine landscapes and provide guidance for adaptation planners seeking to prioritize those places with the highest likelihood of inland salt marsh migration in the near-term.

  8. A comparison of trace metal bioaccumulation and distribution in Typha latifolia and Phragmites australis: implication for phytoremediation.

    PubMed

    Klink, Agnieszka

    2017-02-01

    The aims of the present investigation were to reveal various trace metal accumulation abilities of two common helophytes Typha latifolia and Phragmites australis and to investigate their potential use in the phytoremediation of environmental metal pollution. The concentrations of Fe, Mn, Zn, Cu, Cd, Pb and Ni were determined in roots, rhizomes, stems and leaves of both species studied as well as in corresponding water and bottom sediments from 19 sites selected within seven lakes in western Poland (Leszczyńskie Lakeland). The principal component and classification analysis showed that P. australis leaves were correlated with the highest Mn, Fe and Cd concentrations, but T. latifolia leaves with the highest Pb, Zn and Cu concentrations. However, roots of the P. australis were correlated with the highest Mn, Fe and Cu concentrations, while T. latifolia roots had the highest Pb, Zn and Cd concentrations. Despite the differences in trace metal accumulation ability between the species studied, Fe, Cu, Zn, Pb and Ni concentrations in the P. australis and T. latifolia exhibited the following accumulation scheme: roots > rhizomes > leaves > stems, while Mn decreased in the following order: root > leaf > rhizome > stem. The high values of bioaccumulation factors and low values of translocation factors for Zn, Mn, Pb and Cu indicated the potential application of T. latifolia and P. australis in the phytostabilisation of contaminated aquatic ecosystems. Due to high biomass of aboveground organs of both species, the amount of trace metals stored in these organs during the vegetation period was considerably high, despite of the small trace metals transport.

  9. Evaluation of the functional roles of fungal endophytes of Phragmites australis from high saline and low saline habitats

    USGS Publications Warehouse

    Soares, Marcos Antonio; Li, Hai-Yan; Kowalski, Kurt P.; Bergen, Marshall; Torres, Monica S.; White, James F.

    2016-01-01

    Non-native Phragmites australis decreases biodiversity and produces dense stands in North America. We surveyed the endophyte communities in the stems, leaves and roots of collections of P. australis obtained from two sites with a low and high salt concentration to determine differences in endophyte composition and assess differences in functional roles of microbes in plants from both sites. We found differences in the abundance, richness and diversity of endophytes between the low saline collections (18 species distributed in phyla Ascomycota, Basidiomycota and Stramenopiles (Oomycota); from orders Dothideales, Pleosporales, Hypocreales, Eurotiales, Cantharellales and Pythiales; Shannon H = 2.639; Fisher alpha = 7.335) and high saline collections (15 species from phylum Ascomycota; belonging to orders Pleosporales, Hypocreales, Diaporthales, Xylariales and Dothideales; Shannon H = 2.289; Fisher alpha = 4.181). Peyronellaea glomerata, Phoma macrostoma and Alternaria tenuissima were species obtained from both sites. The high salt endophyte community showed higher resistance to zinc, mercury and salt stress compared to fungal species from the low salt site. These endophytes also showed a greater propensity for growth promotion of rice seedlings (a model species) under salt stress. The results of this study are consistent with the ‘habitat-adapted symbiosis hypothesis’ that holds that endophytic microbes may help plants adapt to extreme habitats. The capacity of P. australis to establish symbiotic relationships with diverse endophytic microbes that enhance its tolerance to abiotic stresses could be a factor that contributes to its invasiveness in saline environments. Targeting the symbiotic associates of P. australis could lead to more sustainable control of non-native P. australis.

  10. Synchrotron micro-scale measurement of metal distributions in Phragmites australis and Typha latifolia root tissue from an urban brownfield site.

    PubMed

    Feng, Huan; Qian, Yu; Gallagher, Frank J; Zhang, Weiguo; Yu, Lizhong; Liu, Changjun; Jones, Keith W; Tappero, Ryan

    2016-03-01

    Liberty State Park in New Jersey, USA, is a "brownfield" site containing various levels of contaminants. To investigate metal uptake and distributions in plants on the brownfield site, Phragmites australis and Typha latifolia were collected in Liberty State Park during the growing season (May-September) in 2011 at two sites with the high and low metal loads, respectively. The objective of this study was to understand the metal (Fe, Mn, Cu, Pb and Zn) concentration and spatial distributions in P. australis and T. latifolia root systems with micro-meter scale resolution using synchrotron X-ray microfluorescence (μXRF) and synchrotron X-ray computed microtomography (μCMT) techniques. The root structure measurement by synchrotron μCMT showed that high X-ray attenuation substance appeared in the epidermis. Synchrotron μXRF measurement showed that metal concentrations and distributions in the root cross-section between epidermis and vascular tissue were statistically different. Significant correlations were found between metals (Cu, Mn, Pb and Zn) and Fe in the epidermis, implying that metals were scavenged by Fe oxides. The results from this study suggest that the expression of metal transport and accumulation within the root systems may be element specific. The information derived from this study can improve our current knowledge of the wetland plant ecological function in brownfield remediation.

  11. Synchrotron micro-scale measurement of metal distributions in Phragmites australis and Typha latifolia root tissue from an urban brownfield site

    DOE PAGES

    Feng, Huan; Qian, Yu; Gallagher, Frank J.; ...

    2015-11-01

    Liberty State Park in New Jersey, USA, is a “brownfield” site containing various levels of contaminants. To investigate metal uptake and distributions in plants on the brownfield site, Phragmites australis and Typha latifolia were collected in Liberty State Park during the growing season (May–September) in 2011 at two sites with the high and low metal loads, respectively. The objective of this study was to understand the metal (Fe, Mn, Cu, Pb and Zn) concentration and spatial distributions in P. australis and T. latifolia root systems with micro-meter scale resolution using synchrotron X-ray microfluorescence (μXRF) and synchrotron X-ray computed microtomography (μCMT)more » techniques. The root structure measurement by synchrotron μCMT showed that high X-ray attenuation substance appeared in the epidermis. Synchrotron μXRF measurement showed that metal concentrations and distributions in the root cross-section between epidermis and vascular tissue were statistically different. Significant correlations were found between metals (Cu, Mn, Pb and Zn) and Fe in the epidermis, implying that metals were scavenged by Fe oxides. The results from this study suggest that the expression of metal transport and accumulation within the root systems may be element specific. The information derived from this study can improve our current knowledge of the wetland plant ecological function in brownfield remediation.« less

  12. Influence of season and salinity on the exudation of aliphatic low molecular weight organic acids (ALMWOAs) by Phragmites australis and Halimione portulacoides roots

    NASA Astrophysics Data System (ADS)

    Rocha, A. Cristina S.; Almeida, C. Marisa R.; Basto, M. Clara P.; Vasconcelos, M. Teresa S. D.

    2015-01-01

    Plant roots have the ability to produce and secrete substances, such as aliphatic low molecular weight organic acids (ALMWOAs), into the rhizosphere. This phenomenon occurs for several purposes, for instance, the detoxification of pollutants. Nevertheless, knowledge about the exudation of such substances from marsh plants roots is still scarce. This work aimed at studying: 1) the ability of marsh plants, freshly collected in estuarine marshes, to liberate ALMWOAs into the surrounding medium and 2) the influence of the physiological cycle of these plants on the exudation of those substances. In vitro experiments were carried out, in different seasons, with Phragmites australis and Halimione portulacoides (two marsh plants widely distributed in Europe). Root exudates were collected in freshwater to which plant specimens, in different physiological stages, were exposed. Both marsh plants were capable of liberating oxalic and citric acids into the surrounding medium. Formic acid was also released by P. australis roots and acetic acid by H. portulacoides. There was a seasonal effect on the liberation of ALMWOAs by both plant roots. Marked changes were registered in the nature and levels of the ALMWOAs liberated and such changes depended upon the season in which the specimens were collected. In growing season, a significantly higher liberation of oxalic and citric acids (and acetic acid but only in H. portulacoides case) was observed. For P. australis, formic acid was only found in the decaying stage (autumn and winter). The nature of the medium (in particular, salinity) was a feature conditioning the exudation of ALMWOAs. Both plants were shown to contribute for the presence of ALMWOAs in marsh rhizosediments (some ALMWOAs were found in pore waters extracted). The nature and extent of this contribution will be however dependent upon plants' physiological stage, in addition to plant species. Therefore, these features should be taken into consideration in the event of

  13. The exogenous particles of heavy metals and/or radionuclide interaction with cellular organelles in Phragmites australis (Cav.) Steudel leaf

    NASA Astrophysics Data System (ADS)

    Corneanu, Gabriel; Corneanu, Mihaela; Craciun, Constantin; Tripon, Septimiu

    2013-04-01

    Phragmites australis (Cav.) Steudel (reed), is a phytoremediatory species, meet in the swampy areas, being a hypperaccumulator for chromium (Calheiros et al., 2008; Ait Ali et al., 2004, a/o). In nature there are cytotypes with a different somatic chromosome number (6x - 16x), with a good adaptation at various environmental conditions. Weis and Weis (2004) consider that reed is an invasive species, sequester more metals than some native species and recommended to use it, in wetlands, for phytoremediation and marsh restoration. Researches performed by Hakmaoui et al. (2007) regarding the ultrastructural effect of cadmium and cooper on reed, evidenced the presence of the ferritin aggregates in the chloroplast stroma, as well as some reversible modifications in chloroplast. In this paper, the ultrastructural features of the leaf in three Phragmites australis genotypes, from the Middle Jiu river valley (Gorj county, Romania), were analyzed: Control (Ţânţăreni village); a population from neighbourhood of TEPP-Turceni; and other population developed at the basis a sterile waste dump of 40 years-old (near Cocoreni village). The heavy metal and radionuclide content of the soil was different in the three sites, with the lowest values in Control and the highest values for many heavy metals (Zn, Mn, Ni, Co, Cd) and radionuclide's (U-238, Ra-226, Pb-210, Bi-214, Pb-214, U-235, Ac-228, Pb-212, Cs-137) on the sterile waste dump. The analysis of the ultrastructural features of the leaf in mature plants revealed some differences between the three Phragmites australis genotypes. The ultrastructural investigations underlined the adaptation of this species against the stress factors (heavy metals and radionuclides). The exogenous particles penetrated the foliar tissue through the epidermis and stomata, being spread in the cells, at the plasmodesmata level, through endoplasmic reticulum, and through the vascular system. The exogenous particles were present on the endoplasmic

  14. Phragmites australis management in the United States: 40 years of methods and outcomes.

    PubMed

    Hazelton, Eric L G; Mozdzer, Thomas J; Burdick, David M; Kettenring, Karin M; Whigham, Dennis F

    2014-01-01

    Studies on invasive plant management are often short in duration and limited in the methods tested, and lack an adequate description of plant communities that replace the invader following removal. Here we present a comprehensive review of management studies on a single species, in an effort to elucidate future directions for research in invasive plant management. We reviewed the literature on Phragmites management in North America in an effort to synthesize our understanding of management efforts, identify gaps in knowledge and improve the efficacy of management. Additionally, we assessed recent ecological findings concerning Phragmites mechanisms of invasion and integrated these findings into our recommendations for more effective management. Our overall goal is to examine whether or not current management approaches can be improved and whether they promote reestablishment of native plant communities. We found: (i) little information on community-level recovery of vegetation following removal of Phragmites; and (ii) most management approaches focus on the removal of Phragmites from individual stands or groups of stands over a relatively small area. With a few exceptions, recovery studies did not monitor vegetation for substantial durations, thus limiting adequate evaluation of the recovery trajectory. We also found that none of the recovery studies were conducted in a landscape context, even though it is now well documented that land-use patterns on adjacent habitats influence the structure and function of wetlands, including the expansion of Phragmites. We suggest that Phragmites management needs to shift to watershed-scale efforts in coastal regions, or larger management units inland. In addition, management efforts should focus on restoring native plant communities, rather than simply eradicating Phragmites stands. Wetlands and watersheds should be prioritized to identify ecosystems that would benefit most from Phragmites management and those where the

  15. Phragmites australis management in the United States: 40 years of methods and outcomes

    PubMed Central

    Hazelton, Eric L. G.; Mozdzer, Thomas J.; Burdick, David M.; Kettenring, Karin M.; Whigham, Dennis F.

    2014-01-01

    Studies on invasive plant management are often short in duration and limited in the methods tested, and lack an adequate description of plant communities that replace the invader following removal. Here we present a comprehensive review of management studies on a single species, in an effort to elucidate future directions for research in invasive plant management. We reviewed the literature on Phragmites management in North America in an effort to synthesize our understanding of management efforts, identify gaps in knowledge and improve the efficacy of management. Additionally, we assessed recent ecological findings concerning Phragmites mechanisms of invasion and integrated these findings into our recommendations for more effective management. Our overall goal is to examine whether or not current management approaches can be improved and whether they promote reestablishment of native plant communities. We found: (i) little information on community-level recovery of vegetation following removal of Phragmites; and (ii) most management approaches focus on the removal of Phragmites from individual stands or groups of stands over a relatively small area. With a few exceptions, recovery studies did not monitor vegetation for substantial durations, thus limiting adequate evaluation of the recovery trajectory. We also found that none of the recovery studies were conducted in a landscape context, even though it is now well documented that land-use patterns on adjacent habitats influence the structure and function of wetlands, including the expansion of Phragmites. We suggest that Phragmites management needs to shift to watershed-scale efforts in coastal regions, or larger management units inland. In addition, management efforts should focus on restoring native plant communities, rather than simply eradicating Phragmites stands. Wetlands and watersheds should be prioritized to identify ecosystems that would benefit most from Phragmites management and those where the

  16. Thermogravimetric-Fourier transform infrared spectrometric analysis of CO2 gasification of reed (Phragmites australis) kraft black liquor.

    PubMed

    Yang, Qing; Yin, Xiuli; Wu, Chuangzhi; Wu, Shubin; Guo, Daliang

    2012-03-01

    CO(2) gasification of the reed (Phragmites australis) kraft black liquor (KBL) and its water-soluble lignin (WSL) was analyzed by thermogravimetry coupled with Fourier transform infrared spectrometry (TG-FTIR). In KBL gasification, major mass loss of KBL occurred between 150 and 1000°C, followed by a further slow mass loss until the heating was stopped and the TG curve leveled off. The TG profiles of the WSL and the KBL were similar during gasification; however, the differential thermogravimetry (DTG) curves and mass decrease from 300°C of the TG curves of the WSL and the KBL were different because of their dissimilar ingredients. The CO formation mechanism was the same and independent of structural types of lignins between reed and wood in their KBL CO(2) gasification.

  17. Impacts of Macondo oil from Deepwater Horizon spill on the growth response of the common reed Phragmites australis: a mesocosm study.

    PubMed

    Judy, Chad R; Graham, Sean A; Lin, Qianxin; Hou, Aixin; Mendelssohn, Irving A

    2014-02-15

    We investigated impacts of Macondo MC252 oil from the Deepwater Horizon (DWH) spill on the common reed Phragmites australis (Cav.) Trin. ex Steud., a dominant species of the Mississippi River Delta. In greenhouse experiments, we simulated the most common DWH oiling scenarios by applying weathered and emulsified Macondo oil to aboveground shoots at varying degrees of coverage (0-100%) or directly to marsh soil at different dosages (0-16 Lm(-)(2)). P. australis exhibited strong resistance to negative impacts when oil was applied to shoots alone, while reductions in above- and belowground plant growth were apparent when oil was applied to the soil or with repeated shoot-oiling. Although soil-oiling compromised plant function, mortality of P. australis did not occur. Our results demonstrate that P. australis has a high tolerance to weathered and emulsified Macondo oil, and that mode of exposure (aboveground versus belowground) was a primary determinant of impact severity.

  18. The Role of Phragmites australis in Mediating Inland Salt Marsh Migration in a Mid-Atlantic Estuary

    PubMed Central

    Smith, Joseph A. M.

    2013-01-01

    Many sea level rise adaptation plans emphasize the protection of adjacent uplands to allow for inland salt marsh migration, but little empirical information exists on this process. Using aerial photos from 1930 and 2006 of Delaware Estuary coastal habitats in New Jersey, I documented the rate of coastal forest retreat and the rate of inland salt marsh migration across 101.1 km of undeveloped salt marsh and forest ecotone. Over this time, the amount of forest edge at this ecotone nearly doubled. In addition, the average amount of forest retreat was 141.2 m while the amount of salt marsh inland migration was 41.9 m. Variation in forest retreat within the study area was influenced by variation in slope. The lag between the amount of forest retreat and salt marsh migration is accounted for by the presence of Phragmites australis which occupies the forest and salt marsh ecotone. Phragmites expands from this edge into forest dieback areas, and the ability of salt marsh to move inland and displace Phragmites is likely influenced by salinity at both an estuary-wide scale and at the scale of local subwatersheds. Inland movement of salt marsh is lowest at lower salinity areas further away from the mouth of the estuary and closer to local heads of tide. These results allow for better prediction of salt marsh migration in estuarine landscapes and provide guidance for adaptation planners seeking to prioritize those places with the highest likelihood of inland salt marsh migration in the near-term. PMID:23705031

  19. Maghemite nanoparticles and ferrous sulfate for the stimulation of iron plaque formation and arsenic immobilization in Phragmites australis.

    PubMed

    Pardo, Tania; Martínez-Fernández, Domingo; de la Fuente, Carlos; Clemente, Rafael; Komárek, Michael; Bernal, M Pilar

    2016-12-01

    Wetland plants are considered as suitable biofilters for the removal of metal(loid)s and other contaminants from waters and wastewaters, due to their ability to accumulate and retain the contaminants in their roots. The iron plaque (IP) on the root surface influences the metal(loid)s retention processes. The stimulation of the IP development on roots of Phragmites australis by the external supply of a novel synthetic nanomaterial (nanomaghemite, nFe2O3) and FeSO4 (alone or in combination) was studied. An hydroponic experiment was carried out to evaluate the iron plaque formation after external iron addition, as well as their influence on arsenic immobilization capacity. Microscopic and spectroscopic techniques were utilized to assess the distribution of Fe and As in the roots. The addition of Fe stimulated the generation of the IP, especially when FeSO4 was involved. The nanoparticles alone were not efficient with regard to IP formation or As adsorption, even though they adhered to the root surface and did not enter into epithelial root cells. The combination of FeSO4 and nFe2O3 was the most effective treatment for improving the As removal capacity, and it seems to be an effective way to enhance the rhizofiltration potential of P. australis in As contaminated (waste)waters.

  20. Role of Rhizophagus irregularis in alleviating cadmium toxicity via improving the growth, micro- and macroelements uptake in Phragmites australis.

    PubMed

    Wang, Li; Huang, Xiaochen; Ma, Fang; Ho, Shih-Hsin; Wu, Jieting; Zhu, Shishu

    2017-02-01

    Arbuscular mycorrhizal (AM) fungi have been used to alleviate heavy metal stress on plant growth and uptake of micro- and macroelements. A greenhouse pot experiment was conducted to verify the effects of AM fungus Rhizophagus irregularis on the growth, physiological characteristics, total Cd, and element uptake of Phragmites australis under different Cd stress (in the range of 0-20 mg L(-1)). The results showed that the symbiosis could effectively alleviate Cd toxicity with greater root biomass, higher photosynthesis rate, and lower levels of malonaldehyde (MDA) and proline than non-mycorrhizal plants could. However, reduced transpiration rate (Tr) and stomatal conductance (g s) indicated R. irregularis protected host plants from Cd stress (≥5 mg L(-1)) via the stomatal closure. Although micro- and macroelements displayed differently in the presence of Cd, higher concentrations were still detected in mycorrhizal plants in contrast to non-mycorrhizal plants. Moreover, step multiple regression significantly demonstrated Pnmax, stem diameter (Sd), and g s were the important factors with regard to total Cd uptake in the symbiosis, but Mn affected to non-mycorrhizal plants. These results suggested R. irregularis could alleviate the competition between Mn and Cd by altering plant physiology. This work clearly demonstrated that R. irregularis can be able to support P. australis growth better even though under high Cd stress (>1 mg L(-1)), suggesting its good potential for practical use in high Cd-contaminated areas.

  1. Uptake and Bioaccumulation of Pentachlorophenol by Emergent Wetland Plant Phragmites australis (Common Reed) in Cadmium Co-contaminated Soil.

    PubMed

    Hechmi, Nejla; Ben Aissa, Nadhira; Abdenaceur, Hassen; Jedidi, Naceur

    2015-01-01

    Despite many studies on phytoremediation of soils contaminated with either heavy metals or organics, little information is available on the effectiveness of phytoremediation of co-occurring metal and organic pollutants especially by using wetland species. Phragmites australis is a common wetland plant and its potential for phytoremediation of cadmium pentachlorophenol (Cd-PCP) co-contaminated soil was investigated. A greenhouse study was executed to elucidate the effects of Cd (0, 10, and 20 mg kg(-1)) without or with PCP (0, 50, and 250 mg kg(-1)) on the growth of the wetland plant P. australis and its uptake, accumulation and removal of pollutant from soils. After 75 days, plant biomass was significantly influenced by interaction of Cd and PCP and the effect of Cd on plant growth being stronger than that of PCP. Coexistence of PCP at low level lessened Cd toxicity to plants, resulting in improved plant growth and increased Cd accumulation in plant tissues. The dissipation of PCP in soils was significantly influenced by interactions of Cd, PCP and plant presence or absence. As an evaluation of soil biological activities after remediation soil enzyme was measured.

  2. Estimation of chlorophyll content of Phragmites australis based on PROSPECT and DART models in the saltmarsh of Yangtze Estuary

    NASA Astrophysics Data System (ADS)

    Zeng, Yuyan; Shi, Runhe; Liu, Pudong; Zhang, Chao; Wang, Jiapeng; Liu, Chaoshun; Chen, Maosi

    2016-09-01

    Phragmites australis is a native dominant specie in the Yangtze Estuary, which plays a key role in the structure and function of wetland ecosystem. One key question is how to estimate the Chlorophyll content quickly and effectively at large scales, which could be used to reflect the growth condition and calculate the vegetation productivity. The aim of this work was to estimate Chlorophyll content of P. australis based on the PROSPECT and DART (Discrete Anisotropic Radiative Transfer) model. A total of 6 widely used Vegetation indices (VIs) were chosen (i.e., Normalized Difference Vegetation Index (NDVI), Structure Insensitive Pigment Index (SIPI), Colouration Index (COI), Simple Ratio Index (SR), Cater Index (CAI), and Red-edge Position Linear Interpolation (REP_Li)) and calculated, and then the relationship between VIs and Cab were analyzed. Results showed that COI and SIPI were sensitive to the leaf chlorophyll content as the chlorophyll content changes at the leaf scale. Meanwhile, no obvious saturation phenomenon was observed for these two indices compared to other indices.

  3. Simultaneous laccase production and color removal by culturing fungus Pycnoporus sp. SYBC-L3 in a textile wastewater effluent supplemented with a lignocellulosic waste Phragmites australis.

    PubMed

    Liu, Jiayang; Cai, Yujie; Liao, Xiangru; Huang, Qingguo; Hao, Zhikui; Hu, Mingming; Zhang, Dabing

    2012-08-01

    We conducted experiments to culture Pycnoporus sp. SYBC-L3 in a medium comprising an industrial waste (dye-containing textile effluent) and a lignocellulosic waste (Phragmites australis) that achieved laccase production while having the color removed from the wastewater. Our experimental results showed that the fungus grew well in liquid submerged cultivation with the diluted textile effluent as the sole culture medium, but relatively low extracellular laccase activity (1.8 U/mL) was produced. Addition of the lignocellulosic biomass enhanced laccase production and color removal. The highest laccase activity was found to be 6.5 U/mL in the presence of Phragmites australis stem. Under this condition, 70 % color removal occurred in the culture medium. This study provided an alternative novel scheme to remove color in textile wastewater while having an economic value added by producing laccase.

  4. Synchrotron X-ray microfluorescence measurement of metal distributions in Phragmites australis root system in the Yangtze River intertidal zone

    SciTech Connect

    Feng, Huan; Zhang, Weiguo; Qian, Yu; Liu, Wenliang; Yu, Lizhong; Yoo, Shinjae; Wang, Jun; Wang, Jia-Jun; Eng, Christopher; Liu, Chang-Jun; Tappero, Ryan

    2016-06-15

    This study investigates the distributions of Br, Ca, Cl, Cr, Cu, K, Fe, Mn, Pb, Ti, V and Zn inPhragmites australisroot system and the function of Fe nanoparticles in scavenging metals in the root epidermis using synchrotron X-ray microfluorescence, synchrotron transmission X-ray microscope measurement and synchrotron X-ray absorption near-edge structure techniques. The purpose of this study is to understand the mobility of metals in wetland plant root systems after their uptake from rhizosphere soils.Phragmites australissamples were collected in the Yangtze River intertidal zone in July 2013. The results indicate that Fe nanoparticles are present in the root epidermis and that other metals correlate significantly with Fe, suggesting that Fe nanoparticles play an important role in metal scavenging in the epidermis.

  5. Synchrotron X-ray microfluorescence measurement of metal distributions in Phragmites australis root system in the Yangtze River intertidal zone

    SciTech Connect

    Feng, Huan; Zhang, Weiguo; Qian, Yu; Liu, Wenliang; Yu, Lizhong; Yoo, Shinjae; Wang, Jun; Wang, Jia -Jun; Eng, Christopher; Liu, Chang -Jun; Tappero, Ryan

    2016-06-15

    This paper investigates the distributions of Br, Ca, Cl, Cr, Cu, K, Fe, Mn, Pb, Ti, V and Zn in Phragmites australis root system and the function of Fe nanoparticles in scavenging metals in the root epidermis using synchrotron X-ray microfluorescence, synchrotron transmission X-ray microscope measurement and synchrotron X-ray absorption near-edge structure techniques. The purpose of this study is to understand the mobility of metals in wetland plant root systems after their uptake from rhizosphere soils. Phragmites australis samples were collected in the Yangtze River intertidal zone in July 2013. The results indicate that Fe nanoparticles are present in the root epidermis and that other metals correlate significantly with Fe, suggesting that Fe nanoparticles play an important role in metal scavenging in the epidermis.

  6. EXPANSION OF PHRAGMITES AUSTRALIS INTO TIDAL WETLANDS OF NORTH AMERICA. (U915648)

    EPA Science Inventory

    Phragmites expansion into tidal wetlands of North America is most extensive along the northern and middle Atlantic coasts, but over 80% of the US coastal wetland area occurs along the Gulf of Mexico and southern Atlantic coasts and may be susceptible to ongoing expansio...

  7. Opaque closed chambers underestimate methane fluxes of Phragmites australis (Cav.) Trin. ex Steud.

    PubMed

    Günther, Anke; Jurasinski, Gerald; Huth, Vytas; Glatzel, Stephan

    2014-04-01

    Closed chamber measurements for methane emission estimation are often carried out with opaque chambers to avoid heating of the headspace. However, mainly in wetlands, some plants possess an internal convective gas transport which quickly responds to changes in irradiation. These plants have also been found to often channel a large part of the released methane in temperate fens. We compare methane fluxes derived from transparent versus opaque chambers on Carex-, Phragmites-, and Typha-dominated stands of a temperate fen. Transparent chamber fluxes almost doubled opaque chamber fluxes in the convective transporting Phragmites stand. In Typha, a trend of higher fluxes determined with the transparent chambers was detectable, whereas in Carex, transparent and opaque chamber fluxes did not differ significantly. Thus, opaque chambers bias the outcome of methane measurements, depending on dominant vegetation. We recommend the use of transparent chambers when determining emissions of convective plants or extrapolating fluxes to larger scales.

  8. Timing of harvest of Phragmites australis (CAV.) Trin. ex Steudel affects subsequent canopy structure and nutritive value of roughage in subtropical highland.

    PubMed

    Tanaka, Takashi S T; Irbis, Chagan; Kumagai, Hajime; Inamura, Tatsuya

    2016-01-15

    In recent decades, constructed wetlands dominated by common reeds [Phragmites australis (CAV.) Trin. ex Steudel] have been utilized for treating nitrogen-rich wastewaters. Although plant harvest is a vegetation management in constructed wetlands for the purpose of improving nutrient removal, harvested biomass has become a problem in many places. The reed has attracted increasing interest for its potential as high-quality roughage for ruminants. Therefore, it is crucial to understand the effect of reed harvest timing on subsequent regrowth, reconstruction of canopy structure, and nutritive value of regrown biomass for roughage when defining an appropriate vegetation management in constructed wetlands. The shoots of common reeds were harvested in January (winter), March (spring), and May (early summer) in a free-water surface constructed wetland in southwest China. Harvesting in winter enhanced the shoot regrowth and concentrations of total digestible nutrients (TDN), probably due to vigorous translocations of nonstructural carbohydrates from rhizomes. Harvesting in spring and early summer decreased aboveground biomass, nitrogen (N) standing stock, and concentrations of TDN. From fifty to 110 days after harvest, the TDN had sharply declined to values similar to non-harvested stands. Thus, to obtain high-quality roughage, it is recommended that regrown shoots be harvested again within a year in the early growing stage after the first harvest in winter.

  9. Effects of lead contamination on the clonal propagative ability of Phragmites australis (common reed) grown in wet and dry environments.

    PubMed

    Zhang, N; Zhang, J W; Yang, Y H; Li, X Y; Lin, J X; Li, Z L; Cheng, L Y; Wang, J F; Mu, C S; Wang, A X

    2015-07-01

    Clonal propagation is important for the survival and maintenance of the common reed Phragmites australis. Pot culture experiments were conducted to investigate the effects of lead (Pb) concentration (0, 500, 1500, 3000, 4500 mg·kg(-1) ) and water stress on the clonal reproductive ability of this species. The Pb concentration found in plant organs, in decreasing order, was roots >shoots >rhizomes. There was a negative relationship between the growth of clonal propagative modules (excluding axillary shoot buds) and Pb concentrations, which caused a decrease in biomass, rhizome growth and number of axillary and apical rhizome buds. Daughter axillary shoots exhibited a tolerance strategy, with no significant change in their number; the axillary and apical rhizome buds, daughter apical rhizome shoots and rhizomes exhibited compensatory growth during the late stage of Pb (excluding 4500 mg·kg(-1) ) treatment in a wet environment. Pb applications above 500 mg·kg(-1) reduced these parameters significantly in the drought treatment, except for the number of axillary shoot buds, which did not change. Our results indicate that clonal propagative resistance to Pb contamination can occur via tolerance strategies, compensatory growth and a Pb allocation strategy, enabling these reeds to maintain population stability in wet environments. However, clonal modular growth and reproductive ability were inhibited significantly by the interaction between drought and Pb, which would cause a decline in P. australis populations in a dry environment. Lead concentrations of 4500 and 500 mg·kg(-1) in soils might meet or exceed the Pb tolerance threshold of clonally propagated reeds in wet and dry environments, respectively.

  10. Biogas properties and enzymatic analysis during anaerobic fermentation of Phragmites australis straw and cow dung: influence of nickel chloride supplement.

    PubMed

    Tian, Yonglan; Zhang, Huayong; Chai, Yang; Wang, Lijun; Mi, Xueyue; Zhang, Luyi; Ware, Maxwell Adam

    2017-02-01

    The importance of nickel (added as NiCl2) on mesophilic anaerobic fermentation of Phragmites australis straw and cow dung was demonstrated by investigating the biogas properties, pH values, organic matter degradation [chemical oxygen demand (COD)] and enzyme activities (cellulase, protease and dehydrogenase) during the fermentation process. The results showed that Ni(2+) addition increased the cumulative biogas yields by >18 % by improving the efficiency of first peak stage and bringing forward the second peak stage. The pH values were not significantly influenced by Ni(2+) addition (p > 0.05). Biogas yields were associated with variations in COD concentrations rather than momentary concentrations. At the start-up stage of fermentation (4th day), the biogas yields increased gradually together with the increase of dehydrogenase activities at elevated Ni(2+) concentrations when cellulase and protease activities were similar in all test groups. It is suggested that Ni(2+) addition was mainly dependent on the methanogenic stage. After the start-up stage, the impact of Ni(2+) addition on biogas production was mainly dependent on its effect on cellulase activities, rather than protease or dehydrogenase activities.

  11. Virulence of oomycete pathogens from Phragmites australis-invaded and noninvaded soils to seedlings of wetland plant species.

    PubMed

    Crocker, Ellen V; Karp, Mary Ann; Nelson, Eric B

    2015-06-01

    Soil pathogens affect plant community structure and function through negative plant-soil feedbacks that may contribute to the invasiveness of non-native plant species. Our understanding of these pathogen-induced soil feedbacks has relied largely on observations of the collective impact of the soil biota on plant populations, with few observations of accompanying changes in populations of specific soil pathogens and their impacts on invasive and noninvasive species. As a result, the roles of specific soil pathogens in plant invasions remain unknown. In this study, we examine the diversity and virulence of soil oomycete pathogens in freshwater wetland soils invaded by non-native Phragmites australis (European common reed) to better understand the potential for soil pathogen communities to impact a range of native and non-native species and influence invasiveness. We isolated oomycetes from four sites over a 2-year period, collecting nearly 500 isolates belonging to 36 different species. These sites were dominated by species of Pythium, many of which decreased seedling survival of a range of native and invasive plants. Despite any clear host specialization, many of the Pythium species were differentially virulent to the native and non-native plant species tested. Isolates from invaded and noninvaded soils were equally virulent to given individual plant species, and no apparent differences in susceptibility were observed between the collective groups of native and non-native plant species.

  12. Diversity, host, and habitat specificity of oomycete communities in declining reed stands (Phragmites australis) of a large freshwater lake.

    PubMed

    Nechwatal, Jan; Wielgoss, Anna; Mendgen, Kurt

    2008-06-01

    We studied the diversity of oomycetes in a declining reed belt (Phragmites australis) of Lake Constance, Germany, using conventional baiting with specific reed and standard oak baits, accompanied by molecular techniques. Apart from an Aphanomyces sp. and a Phytophthora sp., baiting from reed rhizosphere samples from flooded, as well as drier, littoral sites revealed only Pythium spp. A total of 67 oomycete isolates was classified according to PCR-RFLP banding patterns and ITS sequencing, and 18 different sequence types could be separated. The majority of these seemed previously unknown species, as indicated by the degree of similarity to those deposited in nucleotide databases. Species communities in both flooded and drier habitats or both reed and oak baits clearly differed from one another, and only few species occurred in both dry and flooded sites, or in both oak and reed baits. A frequently occurring group of related Pythium species appeared to be specifically associated with reed, and these were the only species that proved pathogenic towards this host in vitro. Our study proved that unexplored natural ecosystems harbour diverse communities of oomycete species with specific habitat and host preferences within close-by, but ecologically contrasting, sites. Among the species isolated, those associated with the predominating plant might accumulate and thus may be reed pathogens of considerable importance.

  13. Testing two potential fates for coastal marshes: Greenhouse gas emissions from native, Phragmites australis-invaded, and permanently inundated zones

    NASA Astrophysics Data System (ADS)

    Moseman-Valtierra, S.; Martin, R.; Tang, J.; Morkeski, K.; China, I.; Brannon, E.; Watson, E. B.

    2014-12-01

    Global changes such as biological invasions and sea level rise can significantly affect GHG emissions from coastal wetlands by changing plant community composition and/or environmental conditions. To first characterize GHG fluxes across major plant-defined marsh zones, CO2, N2O, and CH4 fluxes were compared between S. patens- dominated high marsh and S. alterniflora low marsh during 2012 and 2013 growing seasons in 3 New England marshes. To test how these fluxes may change in response to biological invasions and sea level rise, GHG fluxes were then compared between native, P.australis- invaded, and permanently inundated marsh zones at these sites in 2013 and 2014. GHG emissions were analyzed simultaneously from marsh ecosystems using infrared-based spectrometers connected to static flux chambers. Daytime CO2 uptake rates (ranging on average between -2 and -21 μmol CO2 m-2s-1) were generally greater in S. alterniflora low marsh zones than in S. patens high marsh among all 3 sites. Methane fluxes were generally low in both native marsh zones (< 50 μmol CH4 m-2 h-1) and N2O emissions were rare. However, CO2 uptake and CH4 emissions from P. australis zones were typically more than an order of magnitude greater than those of either native marsh zone. In contrast, permanently inundated marsh soils had similar GHG emissions to native marsh zones. . Though large, the P. australis CH4 emissions are estimated to offset less than 5% of observed CO2 uptake rates based on a global warming potential of 25 (100 years). These results suggest that two alternative fates for coastal marshes in the future- conversion to P. australis marshes or to standing water with sea level rise- will substantially affect CO2 and CH4 emissions. Net impacts on climatic forcing of these ecosystems will depend on how long term C sequestration is affected as these emissions shift.

  14. Nutrient removal through autumn harvest of Phragmites australis and Thypha latifolia shoots in relation to nutrient loading in a wetland system used for polishing sewage treatment plant effluent.

    PubMed

    Toet, Sylvia; Bouwman, Meike; Cevaal, Annechien; Verhoeven, Jos T A

    2005-01-01

    The efficacy and feasibility of annual harvesting of Phragmites australis and Typha latifolia shoots in autumn for nutrient removal was evaluated in a wetland system used for polishing sewage treatment plant (STP) effluent. Aboveground biomass and nutrient dynamics nutrient removal through harvest were studied in parallel ditches with stands of Phragmites or Typha that were mown in October during two successive years. The inflow rate of STP effluent to the ditches was experimentally varied, resulting in pairs of ditches with mean hydraulic retention times (HRT) of 0.3, 0.8, 2.3, and 9.3 days, corresponding to N and P mass loading rates of 122-4190 g N m(-2) yr(-1) and 28.3-994 g P m(-2) yr(-1). Nitrogen and P removal efficiency by harvest of Phragmites and Typha shoots in October increased with increasing HRT, despite the opposite HRT effect on N and P standing stocks. This removal through harvest appeared to be useful in treatment wetlands with N and P mass loading rates lower than approximately 120 g N m(-2) yr(-1) and 30 g P m(-2) yr(-1), corresponding to a HRT of roughly 9 days in the ditches of this wetland system. At the HRT of 9.3 days, the annual mass input to the ditches was reduced through the harvest by 7.0-11% and 4.5 -9.2% for N and P, respectively. At the higher nutrient mass loading rates, the nutrient removal through harvest was insignificant compared to the mass inputs. The vitality of Phragmites and Typha, measured as maximum aboveground biomass, was not affected by the annual cutting of the shoots in autumn over two years. The Typha stands yielded higher N and P removal efficiencies through shoot harvest than the Phragmites stands, which was largely the result of lower decreases in N and P standing stocks between August and October. This difference in nutrient standing stocks between the two species was caused by a combined effect of greater decreases in nutrient concentrations largely due to higher nutrient retranslocation efficiencies of

  15. Modeling the role of the close-range effect and environmental variables in the occurrence and spread of Phragmites australis in four sites on the Finnish coast of the Gulf of Finland and the Archipelago Sea.

    PubMed

    Altartouri, Anas; Nurminen, Leena; Jolma, Ari

    2014-04-01

    Phragmites australis, a native helophyte in coastal areas of the Baltic Sea, has significantly spread on the Finnish coast in the last decades raising ecological questions and social interest and concern due to the important role it plays in the ecosystem dynamics of shallow coastal areas. Despite its important implications on the planning and management of the area, predictive modeling of Phragmites distribution is not well studied. We examined the prevalence and progression of Phragmites in four sites along the Southern Finnish coast in multiple time frames in relation to a number of predictors. We also analyzed patterns of neighborhood effect on the expansion and disappearance of Phragmites in a cellular data model. We developed boosted regression trees models to predict Phragmites occurrences and produce maps of habitat suitability. Various Phragmites spread figures were observed in different areas and time periods, with a minimum annual expansion rate of 1% and a maximum of 8%. The water depth, shore openness, and proximity to river mouths were found influential in Phragmites distribution. The neighborhood configuration partially explained the dynamics of Phragmites colonies. The boosted regression trees method was successfully used to interpolate and extrapolate Phragmites distributions in the study sites highlighting its potential for assessing habitat suitability for Phragmites along the Finnish coast. Our findings are useful for a number of applications. With variables easily available, delineation of areas susceptible for Phragmites colonization allows early management plans to be made. Given the influence of reed beds on the littoral species and ecosystem, these results can be useful for the ecological studies of coastal areas. We provide estimates of habitat suitability and quantification of Phragmites expansion in a form suitable for dynamic modeling, which would be useful for predicting future Phragmites distribution under different scenarios of land

  16. Modeling the role of the close-range effect and environmental variables in the occurrence and spread of Phragmites australis in four sites on the Finnish coast of the Gulf of Finland and the Archipelago Sea

    PubMed Central

    Altartouri, Anas; Nurminen, Leena; Jolma, Ari

    2014-01-01

    Phragmites australis, a native helophyte in coastal areas of the Baltic Sea, has significantly spread on the Finnish coast in the last decades raising ecological questions and social interest and concern due to the important role it plays in the ecosystem dynamics of shallow coastal areas. Despite its important implications on the planning and management of the area, predictive modeling of Phragmites distribution is not well studied. We examined the prevalence and progression of Phragmites in four sites along the Southern Finnish coast in multiple time frames in relation to a number of predictors. We also analyzed patterns of neighborhood effect on the expansion and disappearance of Phragmites in a cellular data model. We developed boosted regression trees models to predict Phragmites occurrences and produce maps of habitat suitability. Various Phragmites spread figures were observed in different areas and time periods, with a minimum annual expansion rate of 1% and a maximum of 8%. The water depth, shore openness, and proximity to river mouths were found influential in Phragmites distribution. The neighborhood configuration partially explained the dynamics of Phragmites colonies. The boosted regression trees method was successfully used to interpolate and extrapolate Phragmites distributions in the study sites highlighting its potential for assessing habitat suitability for Phragmites along the Finnish coast. Our findings are useful for a number of applications. With variables easily available, delineation of areas susceptible for Phragmites colonization allows early management plans to be made. Given the influence of reed beds on the littoral species and ecosystem, these results can be useful for the ecological studies of coastal areas. We provide estimates of habitat suitability and quantification of Phragmites expansion in a form suitable for dynamic modeling, which would be useful for predicting future Phragmites distribution under different scenarios of land

  17. Photochemical Alternation of Phragmites australis Plant Litter: New Insight into the Chemical Evolution of Particulate Organic Matter

    NASA Astrophysics Data System (ADS)

    Carrasquillo, A. J.; Gelfond, C. E.; Kocar, B. D.

    2015-12-01

    The photolysis of natural organic matter (NOM) is a potential pathway for the alteration of material that is not easily biodegraded. Irradiation can alter the physical state of organic matter by facilitating the cycling between the particulate (POM) and dissolved (DOM) pools. However, a detailed understanding of the underlying chemical changes to the material in both phases is lacking. Here, we use a suspension of particles derived from Phragmites australis, a common marsh reed with high lignin content, as our model "recalcitrant" POM substrate. The solution was irradiated for three weeks with regular sampling, and the composition of the POM and the photo-produced DOM were measured separately using a suite of mass spectrometric and spectroscopic techniques. The chemical composition of individual molecules was measured by coupling soft ionization techniques (electrospray (ESI) and matrix assisted laser desorption (MALDI) to high-resolution mass spectrometry. Structural information, including the distribution of the major carbon containing functional groups, was obtained using a combination of FTIR for bulk analyses and scanning transmission x-ray microscopy (STXM) for spatially resolved chemistry. Results are discussed in the context of differences in chemical composition and structure with increased irradiation time for both organic matter pools. We observed a general shift in the mass spectra of POM towards lower molecular weight masses and an increase in the abundance of ions in DOM as a function of irradiation time- hence the larger POM matrix is likely fragmenting into smaller species that are more soluble. Spectroscopic measurements indicate that the abundance of acidic and alcohol functionalities increased with irradiation in both carbon pools. These complementary approaches provide new detailed information about how the chemical composition of recalcitrant NOM evolves as it is exposed to sunlight.

  18. Bioavailability of adsorbed and coprecipitated Cu, Ni, Pb, and Cd on iron and iron/aluminum hydroxide to Phragmites australis.

    PubMed

    Wang, He; Jia, Yongfeng

    2017-01-01

    The bioavailability of heavy metals strongly depends on their speciation in the environment. Adsorption (ADS) and coprecipitation (CPT) on amorphous metal hydroxides are important processes, controlling the fates of heavy metals in an aqueous environment. This work studied the bioavailability of Cu, Cd, Ni, and Pb adsorbed on and/or coprecipitated with amorphous iron and iron/aluminum mixed hydroxides to the wetland plant Phragmites australis. After a 13-day treatment, there was an apparent uptake of the heavy metals by the plant, and the amount of metal bioaccumulation was measurably different for different association forms (ADS vs. CPT). The bioaccumulation of Cd associated with Fe0.5Al0.5(OH)3 was greater than that with Fe(OH)3; the adsorbed metals were found to be more bioavailable than the coprecipitated forms for most of the treatments while the aging treatment significantly reduced the bioaccumulation of ADS metals. In the single metal treatment, root metal concentrations in the Fe(OH)3 ADS system followed the order Ni (68 mg kg(-1)) > Cu (32 mg kg(-1)) > Cd (28 mg kg(-1)) > Pb (9 mg kg(-1)), while the CPT system followed the order of Cu (30 mg kg(-1)) > Ni (22 mg kg(-1)) > Pb (9 mg kg(-1)) > Cd (7 mg kg(-1)). The order of metal accumulation in a combined metal treatment was similar to that for single metal treatments, but observed Ni concentration declines by 22 and 71 % and Cu and Cd concentrations increase by 30 and 50 % (for CPT and ADS treatments, respectively), while Pb concentrations increased by 30~50 % in both of them. When treated with low-molecular-weight organic acids (LMWOAs), metal desorption, indicative of metal oxide bonding strength and metal bioavailability, was consistent with metal accumulation in the plant.

  19. Composting Phragmites australis Cav. plant material and compost effects on soil and tomato (Lycopersicon esculentum Mill.) growth.

    PubMed

    Toumpeli, Anna; Pavlatou-Ve, Athina K; Kostopoulou, Sofia K; Mamolos, Andreas P; Siomos, Anastasios S; Kalburtji, Kiriaki L

    2013-10-15

    Composting organic residues is a friendly to the environment alternative to producing fertilizer. This research was carried out to study the process of composting Phragmites australis Cav. plant material alone or with animal manure on a pilot-scale, to evaluate firstly the quality of the composts produced and secondly, using a pot experiment, the effects of their application on soil physicochemical characteristics and tomato plants development. For the compost production a randomized complete block design was used with five treatments (five compost types) and four replications. For the pot experiment, a completely randomized design was used with 17 treatments (plain soil, soil with synthetic fertilizer and the application of five compost types, at three rates each) and five replications. Compost N increased with composting time, while C/N ratio decreased significantly and by the end it ranged from 43.3 for CM to 22.6 for CY. Compost pH became almost neutral, ranging from 6.73 for CY to 7.21 for CM3Y3AM4 by the end. Compost combinations CY7AM3 and CM7AM3 had a more positive influence on the soil physicochemical characteristics than the others. Soil N, P, Ca and Mg concentrations and the reduction of clay dispersion were the highest when CM7AM3 compost was added. The macro-aggregate stability was the highest for CY7AM3, which also sustained plant growth. The latter compost combination improved most of the soil physicochemical characteristics and plant growth especially, when the application rate was 4% (w/w), which equals to 156 Mg ha(-1).

  20. Growth and nutrient accumulation of Phragmites australis in relation to water level variation and nutrient loadings in a shallow lake.

    PubMed

    Zhao, Ying; Xia, Xinghui; Yang, Zhifeng

    2013-01-01

    Shallow lake eutrophication is a global environmental issue. This study investigated the effects of water level variation and nutrient loadings on the growth and nutrient accumulation of Phragmites australis (reed) by field samplings in Baiyangdian Lake, the largest shallow lake of northern China. The field samplings were conducted in two sites of different nutrient loadings during the whole growth period of reeds, and three types of zones with different water depths were chosen for each site, including the terrestrial zone with water level below the ground, the ecotone zone with the water level varying from belowground to aboveground, and the submerged zone with water level above the ground. The result showed that reed growth was more limited by water level variation than nutrient loadings. The average stem lengths and diameters in terrestrial zones were about 26.3%-27.5% and 7.2%-12.0% higher than those in submerged zones, respectively. Similarly, the terrestrial status increased the aboveground biomass of reeds by 36.6%-51.8% compared with the submerged status. Both the nutrient concentrations and storages in the aboveground reeds were mainly influenced by the nutrient loadings in surface water and sediment rather than the water level variation of the reed growth environment, and the nutrient storages reached their maxima in late August or early September. It was observed that the maximum nitrogen storage occurred in the terrestrial zone with higher nutrient loadings, with the value of 74.5 g/m2. This study suggested that water level variation and nutrient loadings should be considered when using reeds to control and remediate eutrophication of shallow lakes.

  1. Fe plaque-related aquatic uranium retention via rhizofiltration along a redox-state gradient in a natural Phragmites australis Trin ex Steud. wetland.

    PubMed

    Wang, Weiqing; Gert Dudel, E

    2017-03-28

    Studies have revealed that the rhizofiltration is a feasible plant-based technology for aquatic metal/metalloid removal. However, the performance of aquatic U retention via rhizofiltration has not been fully revealed yet. In this study, a field investigation was conducted in a Phragmites australis Trin ex Steud. dominated wetland to estimate the efficiency of Fe plaque (IP)-assisted U rhizofiltration, with redox-state gradient (-179 to 220 mV) and low aquatic U level (66.7 to 92.0 μg l(-1)). The U concentrations were determined in soil, root, and aboveground biomass of P. australis. The IP on root surface was extracted via DCB extraction procedure. The bio-concentration factor (BCF) was applied to evaluate the aquatic U transfer capacity from root to above ground biomass of P. australis. The result suggested that root of P. australis was highly effective for aquatic U uptake via rhizofiltration (BCF 1025 to 1556). It also benefited the real U accumulation in aboveground biomass of P. australis (up to 0.4 mg m(-2)) and related plant-water-soil U recycling. The IP and associated microbial community in rhizosphere was effective mediator for aquatic U retention on root surface (BCF 1162 to 847). The IP-assisted aquatic U rhizofiltration was significantly promoted in relatively reductive environment. It was benefited by the enhanced root uptake of Fe due to lower oxidizers (e.g., DO and NO3(-)) availability. On the other hand, the competitive adsorption effect from co-existing IP-affinitive elements (e.g., As) also possibly impaired the real capacity of IP-assisted aquatic U rhizofiltration via P. australis.

  2. Effects of sediment burial disturbance on macro and microelement dynamics in decomposing litter of Phragmites australis in the coastal marsh of the Yellow River estuary, China.

    PubMed

    Sun, Zhigao; Mou, Xiaojie

    2016-03-01

    From April 2008 to November 2009, a field decomposition experiment was conducted to investigate the effects of sediment burial on macro (C, N) and microelement (Pb, Cr, Cu, Zn, Ni, and Mn) variations in decomposing litter of Phragmites australis in the coastal marsh of the Yellow River estuary. Three one-off sediment burial treatments [no sediment burial (0 mm year(-1), S0), current sediment burial (100 mm year(-1), S10), and strong sediment burial (200 mm year(-1), S20)] were laid in different decomposition sites. Results showed that sediment burials showed significant influence on the decomposition rate of P. australis, in the order of S10 (0.001990 day(-1)) ≈ S20 (0.001710 day(-1)) > S0 (0.000768 day(-1)) (p < 0.05). The macro and microelement in decomposing litters of the three burial depths exhibited different temporal variations except for Cu, Zn, and Ni. No significant differences in C, N, Pb, Cr, Zn, and Mn concentrations were observed among the three burial treatments except for Cu and Ni (p > 0.05). With increasing burial depth, N, Cr, Cu, Ni, and Mn concentrations generally increased, while C, Pb, and Zn concentrations varied insignificantly. Sediment burial was favorable for C and N release from P. australis, and, with increasing burial depth, the C release from litter significantly increased, and the N in litter shifted from accumulation to release. With a few exceptions, Pb, Cr, Zn, and Mn stocks in P. australis in the three treatments evidenced the export of metals from litter to environment, and, with increasing burial depth, the export amounts increased greatly. Stocks of Cu and Ni in P. australis in the S10 and S20 treatments were generally positive, evidencing incorporation of the two metals in most sampling times. Except for Ni, the variations of C, N, Pb, Cr, Cu, Zn, and Mn stocks in P. australis in the S10 and S20 treatments were approximated, indicating that the strong burial episodes (S20) occurred in P. australis marsh in

  3. Synchrotron micro-scale measurement of metal distributions in Phragmites australis and Typha latifolia root tissue from an urban brownfield site

    SciTech Connect

    Feng, Huan; Qian, Yu; Gallagher, Frank J.; Zhang, Weiguo; Yu, Lizhong; Liu, Chang -Jun; Jones, Keith W.; Tappero, Ryan

    2015-11-01

    Liberty State Park in New Jersey, USA, is a “brownfield” site containing various levels of contaminants. To investigate metal uptake and distributions in plants on the brownfield site, Phragmites australis and Typha latifolia were collected in Liberty State Park during the growing season (May–September) in 2011 at two sites with the high and low metal loads, respectively. The objective of this study was to understand the metal (Fe, Mn, Cu, Pb and Zn) concentration and spatial distributions in P. australis and T. latifolia root systems with micro-meter scale resolution using synchrotron X-ray microfluorescence (μXRF) and synchrotron X-ray computed microtomography (μCMT) techniques. The root structure measurement by synchrotron μCMT showed that high X-ray attenuation substance appeared in the epidermis. Synchrotron μXRF measurement showed that metal concentrations and distributions in the root cross-section between epidermis and vascular tissue were statistically different. Significant correlations were found between metals (Cu, Mn, Pb and Zn) and Fe in the epidermis, implying that metals were scavenged by Fe oxides. The results from this study suggest that the expression of metal transport and accumulation within the root systems may be element specific. The information derived from this study can improve our current knowledge of the wetland plant ecological function in brownfield remediation.

  4. Phytotoxicity and accumulation of zinc oxide nanoparticles on the aquatic plants Hydrilla verticillata and Phragmites Australis: leaf-type-dependent responses.

    PubMed

    Song, Uhram; Lee, Sunryung

    2016-05-01

    The phytotoxicity and accumulation of zinc oxide nanoparticles (ZnO NPs) on aquatic plant Hydrilla verticillata and Phragmites australis were investigated using mesocosms. The percentage of dissolved Zn in the ZnO NP treatment solutions was measured along with plant shoot growth, antioxidant enzyme activity, chlorophyll content, and Zn content. The dissolution rate of ZnO NPs in Hoagland solution was inversely related to the concentration. The submerged aquatic plant H. verticillata, growth was reduced during the early stages of the experiment when exposed to the highest ZnO NP concentration (1000 mg/L), whereas the emerged aquatic plant P. australis began to show significantly reduced growth after a few weeks. The measurements of chlorophyll content, antioxidant enzyme activity, and Zn accumulation showed that P. australis was adversely affected by NPs and absorbed more Zn than H. verticillata. The results indicated that physiological differences among aquatic plants, such as whether they use leaves or roots for nutrient and water uptake, led to differences in nanoparticle toxicity. Overall, High ZnO NP concentrations caused significant phytotoxicity on aquatic plants, and low concentrations caused unpredictable phytotoxicity. Therefore, the use and disposal of zinc oxide nanoparticles should be carefully monitored.

  5. Response of N₂O emissions to elevated water depth regulation: comparison of rhizosphere versus non-rhizosphere of Phragmites australis in a field-scale study.

    PubMed

    Gu, Xiao-Zhi; Chen, Kai-Ning; Wang, Zhao-de

    2016-03-01

    Emissions of nitrous oxide (N2O) from wetland ecosystems are globally significant and have recently received increased attention. However, relatively few direct studies of these emissions in response to water depth-related changes in sediment ecosystems have been conducted, despite the likely role they play as hotspots of N2O production. We investigated depth-related differential responses of the dissolved inorganic nitrogen distribution in Phragmites australis (Cav.) Trin. ex Steud. rhizosphere versus non-rhizosphere sediments to determine if they accelerated N2O emissions and the release of inorganic nitrogen. Changes in static water depth and P. australis growth both had the potential to disrupt the distribution of porewater dissolved NH4 (+), NO3 (-), and NO2 (-) in profiles, and NO3 (-) had strong surface aggregation tendency and decreased significantly with depth. Conversely, the highest NO2 (-) contents were observed in deep water and the lowest in shallow water in the P. australis rhizosphere. When compared with NO3 (-), NH4 (+), and NO2 (-), fluxes from the rhizosphere were more sensitive to the effects of water depth, and both fluxes increased significantly at a depth of more than 1 m. Similarly, N2O emissions were obviously accelerated with increasing depth, although those from the rhizosphere were more readily controlled by P. australis. Pearson's correlation analysis showed that water depth was significantly related to N2O emission and NO2 (-) fluxes, and N2O emissions were also strongly dependent on NO2 (-) fluxes (r = 0.491, p < 0.05). The results presented herein provide new insights into inorganic nitrogen biogeochemical cycles in freshwater sediment ecosystems.

  6. Genetic and epigenetic diversity and structure of Phragmites australis from local habitats of the Songnen Prairie using amplified fragment length polymorphism markers.

    PubMed

    Qiu, T; Jiang, L L; Yang, Y F

    2016-08-19

    The genetic and epigenetic diversity and structure of naturally occurring Phragmites australis populations occupying two different habitats on a small spatial scale in the Songnen Prairie in northeastern China were investigated by assessing amplified fragment length polymorphisms (AFLPs) and methylation-sensitive amplified polymorphisms (MSAPs) through fluorescent capillary detection. The two groups of P. australis were located in a seasonal waterlogged low-lying and alkalized meadow with a pH of 8-8.5 and in an alkaline patch without accumulated rainwater and with a pH greater than 10. These groups showed high levels of genetic diversity at the habitat level based on the percentage of polymorphic bands (90.32, 82.56%), Nei's gene diversity index (0.262, 0.248), and the Shannon diversity index (0.407, 0.383). Although little is known about the between-habitat genetic differentiation of P. australis on a small spatial scale, our results implied significant genetic differentiation between habitats. Extensive epigenetic diversity within habitats, along with clear differentiation, was found. Specifically, the former habitat (Habitat 1, designated H1) harbored higher levels of genetic and epigenetic diversity than the latter (Habitat 2, designated H2), and population-level diversity was also high. This study represents one of few attempts to predict habitat-based genetic differentiation of reeds on a small scale. These assessments of genetic and epigenetic variation are integral aspects of molecular ecological studies on P. australis. Possible causes for within- and between-habitat genetic and epigenetic variations are discussed.

  7. Invasion of Old World Phragmites australis in the New World: precipitation and temperature patterns combined with human influences redesign the invasive niche.

    PubMed

    Guo, Wen-Yong; Lambertini, Carla; Li, Xiu-Zhen; Meyerson, Laura A; Brix, Hans

    2013-11-01

    After its introduction into North America, Euro-Asian Phragmites australis became an aggressive invasive wetland grass along the Atlantic coast of North America. Its distribution range has since expanded to the middle, south and southwest of North America, where invasive P. australis has replaced millions of hectares of native plants in inland and tidal wetlands. Another P. australis invasion from the Mediterranean region is simultaneously occurring in the Gulf region of the United States and some countries in South America. Here, we analysed the occurrence records of the two Old World invasive lineages of P. australis (Haplotype M and Med) in both their native and introduced ranges using environmental niche models (ENMs) to assess (i) whether a niche shift accompanied the invasions in the New World; (ii) the role of biologically relevant climatic variables and human influence in the process of invasion; and (iii) the current potential distribution of these two lineages. We detected local niche shifts along the East Coast of North America and the Gulf Coast of the United States for Haplotype M and around the Mississippi Delta and Florida of the United States for Med. The new niche of the introduced Haplotype M accounts for temperature fluctuations and increased precipitation. The introduced Med lineage has enlarged its original subtropical niche to the tropics-subtropics, invading regions with a high annual mean temperature (> ca. 10 °C) and high precipitation in the driest period. Human influence is an important factor for both niches. We suggest that an increase in precipitation in the 20th century, global warming and human-made habitats have shaped the invasive niches of the two lineages in the New World. However, as the invasions are ongoing and human and natural disturbances occur concomitantly, the future distribution ranges of the two lineages may diverge from the potential distribution ranges detected in this study.

  8. Study on the Salini-adaptation Physiology in Different Ecotypes of Phragmites australis in the Yellow River Delta of China: Osmotica and Their Contribution to the Osmotic Adjustment

    NASA Astrophysics Data System (ADS)

    Zhao, K. F.; Feng, L. T.; Zhang, S. Q.

    1999-08-01

    In the Yellow River Delta, there are four ecotypes of Phragmites australis: freshwater swamp reed; salty-water swamp reed; lower salt-meadow reed and higher salt-meadow reed. The growth status, composition and dominance of the reed community were observed. The organic and inorganic osmotica, osmotic potential and osmotic adjustment ability of reeds were determined. The abundance, coverage, plant height, leaf water content and osmotic potential all decreased with increasing salinity of habitats. K+ and sugars are the main osmotica in lower salinity, while Na+ is the main osmoticum in higher salinity. Na+ contents and the osmotic adjustment abilities of roots are higher than those in leaves. Na/K ratios of reeds varied with salinity levels of habitats, being about 1 in higher salinity. Moreover, the contributions of osmotica to the osmotic adjustment change with salinity, the higher the salinity level, the greater the contribution of inorganic osmotica, but the smaller the contribution of organic osmotica.

  9. Copper tolerance of the biomass crops Elephant grass (Pennisetum purpureum Schumach), Vetiver grass (Vetiveria zizanioides) and the upland reed (Phragmites australis) in soil culture.

    PubMed

    Liu, Xinghua; Shen, Yixing; Lou, Laiqing; Ding, Chenglong; Cai, Qingsheng

    2009-01-01

    Pot trials were conducted to study the influence of copper (Cu) on the growth and biomass of Elephant grass (EG, Pennisetum purpureum Schumach), Vetiver grass (VG, Vetiveria zizanioides) and the upland reed (UR, Phragmites australis). Cu toxicity in EG, VG and UR was positively correlated with the total and bioavailable Cu concentrations in the soil. Based on the EC50, dry weights, Cu contents, chlorophyll contents and photosynthesis rates, the Cu tolerance of the three species followed the trend EGNVGNUR. There were no significant differences in the unit calorific values among the different plants, though the total calorific values of EG were higher than those of VG and UR due to its higher biomass. The addition of KH2PO4 to the soil decreased the bioavailability of Cu and the Cu uptake by plants. EG could therefore be a good candidate for growth on Cu-contaminated soils, especially those improved by phosphate.

  10. Zinc, cadmium, and copper mobility and accumulation in reeds (Phragmites australis) in urban sediments from two stormwater infiltration basins

    NASA Astrophysics Data System (ADS)

    Bedell, J.-P.; Saulais, S.; Delolme, C.

    2012-04-01

    Infiltration basins are stormwater management techniques that are widely used to reduce stormwater volume. The settling of stormwater particles leads to a contaminated sediment layer at the basin surface. Phragmites australis used in constructed wetlands are widely present in infiltration basins. Such plant can play a role on the fate of heavy metals either directly by their uptake or indirectly by modification of physico-chemical characteristics of the sediment. The aim of this study is to assess Zn, Cd and Cu potential mobility and their bioaccumulation by reeds during plant's growth in urban sediments offering two different geochemical contexts. Methodology is based on the monitoring (in june, august and december) of physico-chemical characteristics of sediment deposit in two basins. These basins, "Minerve" and "Grézieu", located on both sides of Lyon city are characteristic of two different geochemical context. "Minerve" is in the east and "Grézieu" in the west part. The geology of the eastern part of Lyon is characterized by carbonated fluvio-glacial deposits. In the western part, the subsoil is mainly composed of gneiss and granit. Moreover, 20 cm of gravel and a sand layer were initially added at the surface of the "Grézieu" basin. In "Minerve", a clay material was initially added and a filter trench was built along the basin to allow water infiltration. We characterized the sediment deposit by the identification of their geochemical characteristics (Zn, Cu, Cd, total content, pH, CEC, C/N, carbonates and major elements contents …). Then we studied the potential mobility of the three metals by single chemical extraction (CaCl2 for the exchangeable phase, acetate buffer for the acido-soluble phase and diethylenetriamine-pentaacetic acid (DTPA) for the fraction associated to the organic matter). The accumulation of Zn, Cd and Cu in aerial parts and roots of the reeds was also measured. The results show clearly that "Grézieu" sediment is more enriched in

  11. Effects of high Zn and Pb concentrations on Phragmites australis (Cav.) Trin. Ex. Steudel: Photosynthetic performance and metal accumulation capacity under controlled conditions.

    PubMed

    Bernardini, A; Salvatori, E; Guerrini, V; Fusaro, L; Canepari, S; Manes, F

    2016-01-01

    The response of Phragmites australis (Cav.) Trin. Ex. Steudel to zinc (Zn) and lead (Pb) was studied separately in two hydroponic tests, during a three weeks experiment. The effects on ecophysiology and biomass partitioning were evaluated during the metal treatments and at the recovery, and total metal content and accumulation capacity in different plant organs were assessed. Zn and Pb had different effects on the overall measured parameters, highlighting different mechanism of action. In particular, Zn concentration was higher in roots and, being a micronutrient, it was translocated into leaves, producing a reduction of assimilation rate, stomatal conductance (-71.9 and -81.3% respect to the control plant respectively), and a strong down regulation of photosystems functionality both at PSII and PSI level. Otherwise, Pb was accumulated mainly in the more lignified tissue such as rhizomes, with slightly effect on gas exchange. Chlorophyll a fluorescence highlighted that Pb inhibits the electron transfer process at the PSI donor side, without recovery after the removal of the metal stress. Despite these physiological limitations, P. australis showed a high capacity to accumulate both metals, and only slight reduction of biomass, being therefore a suitable species for phytoremediation interventions.

  12. Maximal stomatal conductance to water and plasticity in stomatal traits differ between native and invasive introduced lineages of Phragmites australis in North America.

    PubMed

    Douhovnikoff, V; Taylor, S H; Hazelton, E L G; Smith, C M; O'Brien, J

    2016-01-27

    The fitness costs of reproduction by clonal growth can include a limited ability to adapt to environmental and temporal heterogeneity. Paradoxically, some facultatively clonal species are not only able to survive, but colonize, thrive and expand in heterogeneous environments. This is likely due to the capacity for acclimation (sensu stricto) that compensates for the fitness costs and complements the ecological advantages of clonality. Introduced Phragmites australis demonstrates great phenotypic plasticity in response to temperature, nutrient availability, geographic gradient, water depths, habitat fertility, atmospheric CO2, interspecific competition and intraspecific competition for light. However, no in situ comparative subspecies studies have explored the difference in plasticity between the non-invasive native lineage and the highly invasive introduced lineage. Clonality of the native and introduced lineages makes it possible to control for genetic variation, making P. australis a unique system for the comparative study of plasticity. Using previously identified clonal genotypes, we investigated differences in their phenotypic plasticity through measurements of the lengths and densities of stomata on both the abaxial (lower) and adaxial (upper) surfaces of leaves, and synthesized these measurements to estimate impacts on maximum stomatal conductance to water (gwmax). Results demonstrated that at three marsh sites, invasive lineages have consistently greater gwmax than their native congeners, as a result of greater stomatal densities and smaller stomata. Our analysis also suggests that phenotypic plasticity, determined as within-genotype variation in gwmax, of the invasive lineage is similar to, or exceeds, that shown by the native lineage.

  13. Maximal stomatal conductance to water and plasticity in stomatal traits differ between native and invasive introduced lineages of Phragmites australis in North America

    PubMed Central

    Douhovnikoff, V.; Taylor, S. H.; Hazelton, E. L. G.; Smith, C. M.; O'Brien, J.

    2016-01-01

    The fitness costs of reproduction by clonal growth can include a limited ability to adapt to environmental and temporal heterogeneity. Paradoxically, some facultatively clonal species are not only able to survive, but colonize, thrive and expand in heterogeneous environments. This is likely due to the capacity for acclimation (sensu stricto) that compensates for the fitness costs and complements the ecological advantages of clonality. Introduced Phragmites australis demonstrates great phenotypic plasticity in response to temperature, nutrient availability, geographic gradient, water depths, habitat fertility, atmospheric CO2, interspecific competition and intraspecific competition for light. However, no in situ comparative subspecies studies have explored the difference in plasticity between the non-invasive native lineage and the highly invasive introduced lineage. Clonality of the native and introduced lineages makes it possible to control for genetic variation, making P. australis a unique system for the comparative study of plasticity. Using previously identified clonal genotypes, we investigated differences in their phenotypic plasticity through measurements of the lengths and densities of stomata on both the abaxial (lower) and adaxial (upper) surfaces of leaves, and synthesized these measurements to estimate impacts on maximum stomatal conductance to water (gwmax). Results demonstrated that at three marsh sites, invasive lineages have consistently greater gwmax than their native congeners, as a result of greater stomatal densities and smaller stomata. Our analysis also suggests that phenotypic plasticity, determined as within-genotype variation in gwmax, of the invasive lineage is similar to, or exceeds, that shown by the native lineage. PMID:26819257

  14. Multi-residue determination of micropollutants in Phragmites australis from constructed wetlands using microwave assisted extraction and ultra-high-performance liquid chromatography tandem mass spectrometry.

    PubMed

    Petrie, Bruce; Smith, Benjamin D; Youdan, Jane; Barden, Ruth; Kasprzyk-Hordern, Barbara

    2017-03-22

    In constructed wetlands micropollutants can be removed from water by phytoremediation. However, micropollutant uptake and metabolism by plants here is poorly understood due to the lack of good analytical approaches. Reported herein is the first methodology developed and validated for the multi-residue determination of 81 micropollutants (pharmaceuticals, personal care products and illicit drugs) in the emergent macrophyte Phragmites australis. The method involved extraction by microwave accelerated extraction (MAE), clean-up using off-line solid phase extraction and analysis by ultra-high-performance liquid chromatography tandem mass spectrometry. Development of the MAE method found the influence of studied variables on micropollutant recovery to be: extraction temperature > sample mass > solvent composition. Validation of the developed extraction protocol revealed method recoveries were in the range 80-120% for the majority of micropollutants. Method quantitation limits (MQLs) were generally <5 ng g(-1) dry weight demonstrating the sensitivity of the methodology. Application of the method to P. australis from a constructed wetland used to treat trickling filter effluent found 17 micropollutants above their MQL, up to concentrations of 200 ng g(-1). Other than uptake, the presence of several metabolites (carbamazepine 10,11 epoxide, desvenlafaxine, 2-ethylidene-1,5-dimethyl-3,3-diphenylpyrrolidine, N-desmethyltramadol and norketamine) indicated metabolism within the plant may also occur. This new analytical methodology will enable a process mass balance of the constructed wetland to be attained for the first time, and thus help understand the role of phytoremediation in micropollutant removal by such systems.

  15. Increased invasive potential of non-native Phragmites australis: elevated CO2 and temperature alleviate salinity effects on photosynthesis and growth.

    PubMed

    Eller, Franziska; Lambertini, Carla; Nguyen, Loc Xuan; Brix, Hans

    2014-02-01

    The prospective rise in atmospheric CO2 and temperature may change the distribution and invasive potential of a species; and intraspecific invasive lineages may respond differently to climate change. In this study, we simulated a future climate scenario with simultaneously elevated atmospheric CO2 and temperature, and investigated its interaction with soil salinity, to assess the effects of global change on the ecophysiology of two competing haplotypes of the wetland grass Phragmites australis, that are invasive in the coastal marshes of North America. The two haplotypes with the phenotypes ‘EU-type’ (Eurasian haplotype) and ‘Delta-type’ (Mediterranean haplotype), were grown at 0‰ and 20‰ soil salinity, and at ambient or elevated climatic conditions (700 ppm CO2, +5 °C) in a phytotron system. The aboveground growth of both phenotypes was highest at the elevated climatic conditions. Growth at 20‰ salinity resulted in declined aboveground growth, lower transpiration rates (E), stomata conductance (gs), specific leaf area, photosynthetic pigment concentrations, and a reduced photosynthetic performance. The negative effects of salinity were, however, significantly less severe at elevated CO2 and temperature than at the ambient climatic conditions. The Delta-type P. australis had higher shoot elongation rates than the EU-type P. australis, particularly at high salinity. The Delta-type also had higher maximum light-saturated rates of photosynthesis (Asat), maximum carboxylation rates of Rubisco (Vcmax), maximum electron transport rates (Jmax), triose phosphate utilization rates (Tp), stomata conductance (gs), as well as higher Rubisco carboxylation-limited, RuBP regeneration-limited and Tp-regeneration limited CO2 assimilation rates than the EU-type under all growth conditions. Our results suggest that the EU-type will not become dominant over the Delta-type, since the Delta-type has superior ecophysiological traits. However, the projected rise in

  16. Biogas production improvement and C/N control by natural clinoptilolite addition into anaerobic co-digestion of Phragmites australis, feces and kitchen waste.

    PubMed

    Wang, Xiaowei; Zhang, Lieyu; Xi, Beidou; Sun, Wenjun; Xia, Xunfeng; Zhu, Chaowei; He, Xiaosong; Li, Mingxiao; Yang, Tianxue; Wang, Pengfei; Zhang, Zhonglei

    2015-03-01

    Anaerobic co-digestion (A co-D) performance of Phragmites australis, feces and kitchen waste with addition of clinoptilolite (one main kind of zeolite) was investigated to evaluate the improvement of biogas/methane production and internal mechanism of nitrogen and organics control. A better biogas/methane production was observed by 10% clinoptilolite (v/v) than bentonite and diatomite, with the shortest lag phase of 0.070d(-1), the max rate of 15.89L/(kgVSday) and ultimate biogas production of 308.2L/kgVS as the modified Gompertz equation predicted. Accordingly, the content of methane in the biogas was increased from 44.10% to 65.30%. Furthermore, the clinoptilolite inhibited the acidification of digestion liquid (optimum pH 7.0-7.5) and enhanced the VFAs (acetic acid, propionic acid and butyric acid) destruction. Moreover, 10% of clinoptilolite optimally enhanced the microbial utilization of Ca(2+)/Mg(2+), controlled the C/N ratio, and improved the biogas production as well as NH3-N/NO3-N inhibition efficiency.

  17. Spatial Genetic Structure in Natural Populations of Phragmites australis in a Mosaic of Saline Habitats in the Yellow River Delta, China

    PubMed Central

    Gao, Lexuan; Tang, Shaoqing; Zhuge, Liqiong; Nie, Ming; Zhu, Zhu; Li, Bo; Yang, Ji

    2012-01-01

    Determination of spatial genetic structure (SGS) in natural populations is important for both theoretical aspects of evolutionary genetics and their application in species conservation and ecological restoration. In this study, we examined genetic diversity within and among the natural populations of a cosmopolitan grass Phragmites australis (common reed) in the Yellow River Delta (YRD), China, where a mosaic of habitat patches varying in soil salinity was detected. We demonstrated that, despite their close geographic proximity, the common reed populations in the YRD significantly diverged at six microsatellite loci, exhibiting a strong association of genetic variation with habitat heterogeneity. Genetic distances among populations were best explained as a function of environmental difference, rather than geographical distance. Although the level of genetic divergence among populations was relatively low (F’ST = 0.073), weak but significant genetic differentiation, as well as the concordance between ecological and genetic landscapes, suggests spatial structuring of genotypes in relation to patchy habitats. These findings not only provided insights into the population dynamics of common reed in changing environments, but also demonstrated the feasibility of using habitat patches in a mosaic landscape as test systems to identify appropriate genetic sources for ecological restoration. PMID:22916244

  18. Effect of Cd⁺² on phosphate solubilizing abilities and hydrogen peroxide production of soil-borne micromycetes isolated from Phragmites australis-rhizosphere.

    PubMed

    Zúñiga-Silva, Jose Roberto; Chan-Cupul, Wilberth; Kuschk, Peter; Loera, Octavio; Aguilar-López, Ricardo; Rodríguez-Vázquez, Refugio

    2016-03-01

    The aims of this work were to evaluate the phosphate-solubilization and hydrogen peroxide (H2O2) production by the soil-borne micromycetes, Aspergillus japonicus, Penicillium italicum and Penicillium dipodomyicola, isolated from Phragmites australis rhizosphere and to study the effect of several concentrations of Cadmium (Cd(2+)) on both variables. Our results showed that P. italicum achieved a higher P-solubilization and H2O2 production than A. japonicus and P. dipodomyicola, as only P. italicum showed a positive correlation (R(2) = 0.71) between P-solubilization and H2O2 production. In dose-response assays, P. italicum was also more tolerant to Cd(2+) (0.31 mM) in comparison to A. japonicus (0.26 mM). Analysis of the 2(4) factorial experimental design showed that P-solubilization by P. italicum was negatively affected by increases in Cd(2+) (p = 0.04) and yeast extract (p = 0.02) in the culture medium. The production of H2O2 was positively affected only by glucose (p = 0.002). Fungal biomass production was reduced significantly (p = 0.0009) by Cd(2+) and increased (p = 0.0003) by high glucose concentration in the culture medium. The tolerance and correlation between P-solubilization and H2O2 production in the presence of Cd(2+) was strain and species dependent. The effects of Cd(2+), glucose, ammonium sulfate and yeast extract on those variables were evaluated through a two-level factorial design. P. italicum is promising for P-solubilization in soils contaminated with Cd(2+) and may be an alternative for manufacture of biofertilizers to replace chemical fertilizers.

  19. The impact of invasive plants on tidal-marsh vertebrate species: common reed (Phragmites australis) and smooth cordgrass (Spartina alterniflora) as case studies

    USGS Publications Warehouse

    Guntenspergen, Glenn R.; Nordby, J. Cully

    2006-01-01

    Large areas of tidal marsh in the contiguous US and the Maritime Provinces of Canada are threatened by invasive plant species. Our understanding of the impact these invasions have on tidal-marsh vertebrates is sparse. In this paper, we focus on two successful invasive plant taxa that have spread outside their native range --common reed (Phragmites australis) and smooth cordgrass (Spartina a/terniflora). A cryptic haplotype of common reed has expanded its range in Atlantic Coast tidal marshes and smooth cordgrass, a native dominant plant of Atlantic Coast low-marsh habitat, has expanded its range and invaded intertidal-marsh habitats of the Pacific Coast. The invasions of common reed in Atlantic Coast tidal marshes and smooth cordgrass in Pacific Coast tidal marshes appear to have similar impacts. The structure and composition of these habitats has been altered and invasion and dominance by these two taxa can lead to profound changes in geomorphological processes, altering the vertical relief and potentially affecting invertebrate communities and the entire trophic structure of these systems. Few studies have documented impacts of invasive plant taxa on tidal-marsh vertebrate species in North America. However, habitat specialists that are already considered threatened or endangered are most likely to be affected. Extensive experimental studies are needed to examine the direct impact of invasive plant species on native vertebrate species. Careful monitoring of sites during the initial stages of plant invasion and tracking ecosystem changes through time are essential. Since tidal marshes are the foci for invasion by numerous species, we also need to understand the indirect impacts of invasion of these habitats on the vertebrate community. We also suggest the initiation of studies to determine if vertebrate species can compensate behaviorally for alterations in their habitat caused by invasive plant species, as well as the potential for adaptation via rapid evolution

  20. Practical use of Phragmites australis to study evapotranspiration in a wetland zone of Lake Balaton (southwest Hungary)

    NASA Astrophysics Data System (ADS)

    Anda, Angela; Soos, Gabor; Teixeira da Silva, Jaime A.

    2017-02-01

    In the present study, evapotranspiration ( ET) data from a common reed-dominated wetland and its meteorological controls was analysed using measured ET ( ET m) in compensation evapotranspirometers. Six seasons in the time period between 2003 and 2012 were assessed with the objective of converting theoretical observations into long-term practical use. They reveal the effects of annual fluctuations and allow for a more exact understanding of the results of ET losses, which remain an elusive and substantial part of the hydrologic budget particularly in wetland habitats. Daily measured ET rates were strongly influenced by weather variables causing considerable variation of ET characteristics between the two distinguished season types. The results of multiple stepwise regression analysis showed that the major meteorological elements impacting the sum of seasonal ET was much higher in the warm growing seasons (857 mm), due to increased available energy for ET, than in the cool season (385 mm). The sum of average ET totalled 778.6 mm over measurements. A simplified water budget analysis confirmed that adequate water volume, caused by precipitation, entered the Kis-Balaton wetland (KBW) area during the cool season. Conversely, in warm seasons, only 21.5 % of total ET resulted from rainfall, accentuating its seasonality in wetland. This information about annual variability of long-term ET values would assist in finding an ideal solution for determining the proper water level needed. The current balance of habitat types in wetland should be permanently assessed by selection of the suitable water level in order to sustain the most appropriate wetland ecological conditions.

  1. Chemical Control of Invasive Phragmites in a Great Lakes Marsh: A Field Demonstration

    DTIC Science & Technology

    2013-04-01

    specific rhizome segments of Phragmites australis. Environmental and Experimental Botany 57: 9-18. Blossey, B., and J. McCauley. 2000. A plan for...Meyerson, and K. Saltonstall. 1999. Expansion of Phragmites australis into tidal wetlands of North America. Aquatic Botany 64:261-273. Derr, J. F. 2008...Phragmites australis in the Delta Marsh, Manitoba. Canadian Journal of Botany 63:1864-1869. Tulbure, M. G., and C. A. Johnston. 2010. Environmental

  2. Exploring the borders of European Phragmites within a cosmopolitan genus

    PubMed Central

    Lambertini, Carla; Sorrell, Brian K.; Riis, Tenna; Olesen, Birgit; Brix, Hans

    2012-01-01

    Background and aims Two Phragmites australis taxa are recognized in Europe: P. australis ssp. altissimus, also known as Phragmites isiaca, in the Mediterranean region and P. australis in the temperate region. Another taxonomic group in the Mediterranean is Phragmites frutescens. European genotypes are diverse genetically, cytologically and morphologically, and are related to African, Asiatic and American genotypes. We investigated chloroplast DNA (cpDNA) diversity in Europe and defined the current borders of the European gene pool. Methodology We analysed chloroplast variation with parsimony and genetic distance methods, and compared it with that of nuclear amplified fragment length polymorphism and microsatellites. We also investigated the phenological pattern of 188 genotypes collected worldwide in a common garden in Denmark. We assumed that non-flowering genotypes could indicate climatic, geographic and/or reproductive barriers to dispersal and would have been recorded in the genetic pattern as groups genetically isolated from, or within, the European pool. Principal results The European P. australis gene pool extends from North America to the Far East and South Africa. However, African and North American genotypes are differentiating from the European genotypes. Mediterranean P. australis is genetically different from temperate P. australis and shares several similarities with Phragmites mauritianus in Africa and Phragmites karka in Asia. Phragmites frutescens shares the cpDNA sequences with both these tropical species. Two DNA bands can distinguish Mediterranean P. australis from P. frutescens and P. mauritianus and from temperate P. australis, and reveal possible hybrids among these species in the Mediterranean region. Phenological data confirmed possible gene flow within the temperate region of Europe, whereas the Mediterranean genotypes did not set inflorescences in Denmark, suggesting reproductive barriers between temperate and Mediterranean P. australis

  3. Identification of Phragmites australis and Spartina alterniflora in the Yangtze Estuary between Bayes and BP neural network using hyper-spectral data

    NASA Astrophysics Data System (ADS)

    Liu, Pudong; Zhou, Jiayuan; Shi, Runhe; Zhang, Chao; Liu, Chaoshun; Sun, Zhibin; Gao, Wei

    2016-09-01

    The aim of this work was to identify the coastal wetland plants between Bayes and BP neural network using hyperspectral data in order to optimize the classification method. For this purpose, we chose two dominant plants (invasive S. alterniflora and native P. australis) in the Yangtze Estuary, the leaf spectral reflectance of P. australis and S. alterniflora were measured by ASD field spectral machine. We tested the Bayes method and BP neural network for the identification of these two species. Results showed that three different bands (i.e., 555 nm 711 nm and 920 nm) could be identified as the sensitive bands for the input parameters for the two methods. Bayes method and BP neural network prediction model both performed well (Bayes prediction for 88.57% accuracy, BP neural network model prediction for about 80% accuracy), but Bayes theorem method could give higher accuracy and stability.

  4. Base to Tip and Long-Distance Transport of Sodium in the Root of Common Reed [Phragmites australis (Cav.) Trin. ex Steud.] at Steady State Under Constant High-Salt Conditions.

    PubMed

    Fujimaki, Shu; Maruyama, Teppei; Suzui, Nobuo; Kawachi, Naoki; Miwa, Eitaro; Higuchi, Kyoko

    2015-05-01

    We analyzed the directions and rates of translocation of sodium ions (Na(+)) within tissues of a salt-tolerant plant, common reed [Phragmites australis (Cav.) Trin. ex Steud.], and a salt-sensitive plant, rice (Oryza sativa L.), under constant high-salt conditions using radioactive (22)Na tracer and a positron-emitting tracer imaging system (PETIS). First, the test plants were incubated in a nutrient solution containing 50 mM NaCl and a trace level of (22)Na for 24 h (feeding step). Then the original solution was replaced with a fresh solution containing 50 mM NaCl but no (22)Na, in which the test plants remained for >48 h (chase step). Non-invasive dynamic visualization of (22)Na distribution in the test plants was conducted during feeding and chase steps with PETIS. Our results revealed that (22)Na was absorbed in the roots of common reed, but not transported to the upper shoot beyond the shoot base. During the chase step, a basal to distal movement of (22)Na was detected within the root tissue over >5 cm with a velocity of approximately 0.5 cm h(-1). On the other hand, (22)Na that was absorbed in the roots of rice was continuously translocated to and accumulated in the whole shoot. We concluded that the basal roots and the shoot base of common reed have constitutive functions of Na(+) exclusion only in the direction of root tips, even under constant high-salt conditions. This function apparently may contribute to the low Na(+) concentration in the upper shoot and high salt tolerance of common reed.

  5. VEGETATION TYPE AND THE INTERTIDAL MACROINVERTEBRATE FAUNA OF A BRACKISH MARSH: PHRAGMITES VS. SPARTINA

    EPA Science Inventory

    The responses of tidal marsh macroinvertebrate assemblages to the conversion of Spartina alterniflora marshes to marshes dominated by the invasive reed, Phragmites australis, are poorly understood. Changes in edaphic, vegetative, hydrological, and detrital conditions that attend ...

  6. Ecosystem services of Phragmites in North America with emphasis on habitat functions

    PubMed Central

    Kiviat, Erik

    2013-01-01

    Phragmites australis (common reed) is widespread in North America, with native and non-native haplotypes. Many ecologists and wetland managers have considered P. australis a weed with little value to the native biota or human society. I document important ecosystem services of Phragmites including support for many common and rare species of plants and animals. This paper is based on an extensive review of the ecology and natural history literature, discussions with field workers, and observations in 13 US states and one Canadian province during the past 40 years. Phragmites sequesters nutrients, heavy metals and carbon, builds and stabilizes soils, and creates self-maintaining vegetation in urban and industrial areas where many plants do not thrive. These non-habitat ecosystem services are proportional to biomass and productivity. Phragmites was widely used by Native Americans for many purposes; the most important current direct use is for the treatment of wastes. Most of the knowledge of non-habitat ecosystem services is based on studies of P. australis haplotype M (an Old World haplotype). Phragmites also has habitat functions for many organisms. These functions depend on the characteristics of the landscape, habitat, Phragmites stand, species using Phragmites and life history element. The functions that Phragmites provides for many species are optimal at lower levels of Phragmites biomass and extent of stands. Old World Phragmites, contrary to many published statements, as well as North American native Phragmites, provide valuable ecosystem services including products for human use and habitat functions for other organisms. Phragmites stands may need management (e.g. thinning, fragmentation, containment or removal) to create or maintain suitable habitat for desired species of animals and plants.

  7. Aurora Australis

    NASA Video Gallery

    Video of the Aurora Australis taken by the crew of Expedition 29 on board the International Space Station. This sequence of shots was taken September 17, 2011 from 17:22:27 to 17:45:12 GMT, on an a...

  8. Advancing the science of microbial symbiosis to support invasive species management: a case study on Phragmites in the Great Lakes

    PubMed Central

    Kowalski, Kurt P.; Bacon, Charles; Bickford, Wesley; Braun, Heather; Clay, Keith; Leduc-Lapierre, Michèle; Lillard, Elizabeth; McCormick, Melissa K.; Nelson, Eric; Torres, Monica; White, James; Wilcox, Douglas A.

    2015-01-01

    A growing body of literature supports microbial symbiosis as a foundational principle for the competitive success of invasive plant species. Further exploration of the relationships between invasive species and their associated microbiomes, as well as the interactions with the microbiomes of native species, can lead to key new insights into invasive success and potentially new and effective control approaches. In this manuscript, we review microbial relationships with plants, outline steps necessary to develop invasive species control strategies that are based on those relationships, and use the invasive plant species Phragmites australis (common reed) as an example of how development of microbial-based control strategies can be enhanced using a collective impact approach. The proposed science agenda, developed by the Collaborative for Microbial Symbiosis and Phragmites Management, contains a foundation of sequential steps and mutually-reinforcing tasks to guide the development of microbial-based control strategies for Phragmites and other invasive species. Just as the science of plant-microbial symbiosis can be transferred for use in other invasive species, so too can the model of collective impact be applied to other avenues of research and management. PMID:25745417

  9. Advancing the science of microbial symbiosis to support invasive species management: a case study on Phragmites in the Great Lakes.

    PubMed

    Kowalski, Kurt P; Bacon, Charles; Bickford, Wesley; Braun, Heather; Clay, Keith; Leduc-Lapierre, Michèle; Lillard, Elizabeth; McCormick, Melissa K; Nelson, Eric; Torres, Monica; White, James; Wilcox, Douglas A

    2015-01-01

    A growing body of literature supports microbial symbiosis as a foundational principle for the competitive success of invasive plant species. Further exploration of the relationships between invasive species and their associated microbiomes, as well as the interactions with the microbiomes of native species, can lead to key new insights into invasive success and potentially new and effective control approaches. In this manuscript, we review microbial relationships with plants, outline steps necessary to develop invasive species control strategies that are based on those relationships, and use the invasive plant species Phragmites australis (common reed) as an example of how development of microbial-based control strategies can be enhanced using a collective impact approach. The proposed science agenda, developed by the Collaborative for Microbial Symbiosis and Phragmites Management, contains a foundation of sequential steps and mutually-reinforcing tasks to guide the development of microbial-based control strategies for Phragmites and other invasive species. Just as the science of plant-microbial symbiosis can be transferred for use in other invasive species, so too can the model of collective impact be applied to other avenues of research and management.

  10. Advancing the science of microbial symbiosis to support invasive species management: a case study on Phragmites in the Great Lakes

    USGS Publications Warehouse

    Kowalski, Kurt P.; Bacon, Charles R.; Bickford, Wesley A.; Braun, Heather A.; Clay, Keith; Leduc-Lapierre, Michele; Lillard, Elizabeth; McCormick, Melissa K.; Nelson, Eric; Torres, Monica; White, James W. C.; Wilcox, Douglas A.

    2015-01-01

    A growing body of literature supports microbial symbiosis as a foundational principle for the competitive success of invasive plant species. Further exploration of the relationships between invasive species and their associated microbiomes, as well as the interactions with the microbiomes of native species, can lead to key new insights into invasive success and potentially new and effective control approaches. In this manuscript, we review microbial relationships with plants, outline steps necessary to develop invasive species control strategies that are based on those relationships, and use the invasive plant species Phragmites australis (common reed) as an example of how development of microbial-based control strategies can be enhanced using a collective impact approach. The proposed science agenda, developed by the Collaborative for Microbial Symbiosis andPhragmites Management, contains a foundation of sequential steps and mutually-reinforcing tasks to guide the development of microbial-based control strategies for Phragmites and other invasive species. Just as the science of plant-microbial symbiosis can be transferred for use in other invasive species, so too can the model of collective impact be applied to other avenues of research and management.

  11. Aurora Australis

    NASA Technical Reports Server (NTRS)

    1991-01-01

    Red and Green colors predominate in this view of the Aurora Australis photographed from the Space Shuttle Discovery (STS-39) in May 1991 at the peak of the last geomagnetic maximum. The payload bay and tail of the shuttle can be seen on the left hand side of the picture. Auroras are caused when high-energy electrons pour down from the Earth's magnetosphere and collide with atoms. Red aurora occurs from 200 km to as high as 500 km altitude and is caused by the emission of 6300 Angstrom wavelength light from oxygen atoms. Green aurora occurs from about 100 km to 250 km altitude and is caused by the emission of 5577 Angstrom wavelength light from oxygen atoms. The light is emitted when the atoms return to their original unexcited state. At times of peaks in solar activity, there are more geomagnetic storms and this increases the auroral activity viewed on Earth and by astronauts from orbit.

  12. EFFECT OF SALINITY ON THE COMMON REED, FRAGMITES AUSTRALIS, IN A RESTORED MARSH

    EPA Science Inventory

    Tidal wetlands have undergone extensive degradation throughout the years because of interference with tidal flow from construction, dredging, and invasion of non-native plants such Phragmites australis. In 1956, a 4-lane highway was constructed in Galilee, Rhode Island, USA, cr...

  13. Macroinvertebrate Community Responses to the Chemical Removal of Phragmites in a Lake Erie Coastal Wetland

    NASA Astrophysics Data System (ADS)

    Kulesza, A. E.; Holomuzki, J. R.; Klarer, D. M.

    2005-05-01

    The invasive giant reed, Phragmites australis, can quickly form near-monotypic stands in North American wetlands, and as a result, sometimes reduce system biodiversity. However, the effects of Phragmites, and of the glyphosate herbicides used to control it, on trophic structure in benthic communities in these systems are less well known. Our study compares macroinvertebrate, algal, and juvenile fish diversity in replicate 10 x 5 m stands of Typha angustifolia (narrow-leaf cattail), glyphosate-sprayed Phragmites, and unsprayed Phragmites in a Lake Erie coastal wetland in Huron, Ohio. Macroinvertebrate diversity and proportions of functional feeding groups did not differ among stand types. However, overall densities of macroinvertebrates did vary among stands. Snails and larval chironomids and odonates were typically higher in Phragmites than in Typha stands. Interactions between changing water levels, algal densities, and prevailing flow patterns partly explain these outcomes. Ovipositing adult odonates did not prefer a particular stand type. Similarly, captures of juvenile fish did not vary among stands. Our results suggest that Phragmites, at least in small to moderately sized-patches, and herbicide application to these patches, does not detrimentally affect diversity in wetland, benthic communities.

  14. Role of plant-mediated gas transport in CH4 emissions from Phragmites-dominated peatlands

    NASA Astrophysics Data System (ADS)

    van den Berg, Merit; Ingwersen, Joachim; van den Elzen, Eva; Lamers, Leon P. M.; Streck, Thilo

    2016-04-01

    A large part of the methane (CH4) produced in peatlands is directly oxidized and the extent of its oxidation depends on the gas transport pathway. In wetland ecosystems, CH4 can be transported from the soil to the atmosphere via diffusion, ebullition and via aerenchyma of roots and stems of vascular plants. Compared to other wetland plants, the very common species Phragmites australis (Common reed) appears to have a high ability to transport gases between the soil and atmosphere. The gas exchange within Phragmites plants takes place via convective flow through the culm, which is believed to be achieved by a humidity-induced pressure gradient and is more than 5-times as efficient as diffusion. By this mechanism, CH4 surpasses the upper (oxic) soil layers and therefore oxidation of CH4 may well be reduced. On the other hand, transport of oxygen in Phragmites plants tends to enhance O2concentration in the rhizosphere, which will foster CH4oxidation in deeper soil layers. It is therefore unknown whether humidity-induced convection leads to higher or lower overall CH4 emission in Phragmites, which is essential to understand their role in the emissions from these very common peatland types. To investigate whether this internal gas transport mechanism of reed promotes or reduces CH4 fluxes to the atmosphere, we conducted manipulative field experiments in a large Phragmites peatland in South-West Germany in October 2014 and July 2015. Using large chambers, we compared CH4 fluxes from intact plots, plots with cut reed, and plots with cut + sealed reed to exclude gas transport through the plants. Additionally, pore water samples from the plots were analyzed for possible changes in soil chemistry due to the change of oxygen transport into the soil by the treatments. Based on our results, we will explain the potential role of rhizosphere oxygenation and convective flow on CH4 emissions from Phragmites-dominated peatlands in relation to other environmental condition.

  15. Aurora Australis, Sinuous Loop

    NASA Technical Reports Server (NTRS)

    1991-01-01

    This view of the Aurora Australis or Southern Lights (location unknown) shows a sinuous looping band of airglow above the Earth Limb. Calculated to be in the 80 - 120 km altitude region, auroral activity is due to exitation of atomic oxygen in the upper atmosphere by radiation from the van Allen Radiation Belts and is most common above the 65 degree north and south latitude range during the spring and fall of the year.

  16. Aurora Australis, Red Crown

    NASA Technical Reports Server (NTRS)

    1991-01-01

    This view of the Aurora Australis or Southern Lights (location unknown) shows a spiked band of red airglow called a 'Red Crown' above the Earth Limb. Calculated to be in the 80 - 120 km altitude region, auroral activity is due to exitation of atomic oxygen in the upper atmosphere by radiation from the van Allen Radiation Belts and is most common above the 65 degree north and south latitude range during the spring and fall of the year.

  17. Aurora Australis over Indian Ocean

    NASA Video Gallery

    Video of the Aurora Australis taken by the crew of Expedition 28 on board the International Space Station. This sequence of shots was taken September 7, 2011 from 17:38:03 to 17:49:15 GMT, from the...

  18. Aurora Australis, Seen From Space

    NASA Video Gallery

    This video of the Aurora Australis was created from a sequence of still shots taken by astronauts on board the International Space Station. The images were acquired on September 11, 2011 as the ISS...

  19. [Environmental Effect of Substrate Amelioration on Lake: Effects on Phragmites communis Growth and Photosynthetic Fluorescence Characteristics].

    PubMed

    Yu, Ju-hua; Zhong, Ji-cheng; Fan, Cheng-xin; Huang, Wei; Shang, Jing-ge; Gu, Xiao-zhi

    2015-12-01

    Growth of rooted aquatic macrophytes was affected by the nature and composition of lake bottom sediments. Obviously, it has been recognized as an important ecological restoration measure by improving lake substrate and then reestablishing and restoring aquatic macrophytes in order to get rid of the environmental problem of lake. This study simulated five covering thickness to give an insight into the influence of substrate amelioration on Phragmites communis growth and photosynthetic fluorescence characteristics. The results showed that the total biomass, plant height, leaf length and leaf width of Phragmites communis under capping 5 cm were much more significant than those of capping 18 cm (P < 0.01), at the 120 d, the underground: shoot biomass ratio and fine root: underground biomass ratio were also much higher than those of other treatments (P < 0.05), which indicated that capping 18 cm treatment would significantly inhibit the growth of Phragmites communis , but the growth of control group Phragmites communis was slightly constrained by eutrophicated sediment. In addition, as the capping thickness growing, the underground: shoot biomass ratio of the plant would be reduced dramatically, in order to acquire much more nutrients from sediment for plant growing, the underground biomass of Phragmites communis would be preferentially developed, especially, the biomass of fine root. However, Photosystem II (PS II) photochemical efficiency (Fv/Fm), quantum yield (Yield), photochemical quenching (qP), non-photochemical quenching (qN) of Phragmites communis under different treatments had no significant differences (P > 0.05), furthermore, with much greater capping thickness, the photosynthesis structure of PS II would be much easier destroyed, and PS II would be protected by increasing heat dissipating and reducing leaf photosynthetic area and leaf light-captured pigment contents. In terms of the influence of sediment amelioration by soil exchange on the growth and

  20. LANDSCAPE-SCALE MONITORING OF AN OPPORTUNIST: PHRAGMITES AUSTRALIS (CAV) STEUDEL IN GREAT LAKES COASTAL WETLANDS

    EPA Science Inventory

    Coastal wetlands of the Laurentian Great Lakes (LGL) are among the most fragmented ecosystems in the world, with a long history of human-induced disturbances, primarily as a result of agricultural conversions and hydrologic changes. A substantial number of remnant LGL coastal wet...

  1. Identifying, Developing and Releasing Insect Biocontrol Agents for the Management of Phragmites australis

    DTIC Science & Technology

    2013-07-01

    largely on tests using first instars and either potted plants or stem sections. In addition, adult choice experiments have been conducted in Europe...The reason for different testing scenarios is that they all have various levels of resembling a field situation with the most reductionist (no- choice ...screening procedures also use increasing levels of complexity from no- choice to single- choice , to multiple- choice and from caged tests to open field

  2. A COMPARISON OF PHRAGMITES AUSTRALIS IN FRESHWATER AND BRACKISH MARSH ENVIRONMENTS IN NORTH AMERICA. (U915648)

    EPA Science Inventory

    The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Concl...

  3. [Flavonoids of Cuscuta australis R. Br].

    PubMed

    Guo, H; Li, J

    1997-01-01

    Six flavonoids were isolated from the seed of Cuscuta australis and four of them were identified as kaempferol, quercetin, astragalin and hyperoside. Hyperoside was obtained from this plant for the first time. In comparison with the flavonoids in C. chinensis, it is found that quercetin and its glycoside are the main flavonoids in C. australis. This result suggests that the flavonoids can be used to distinguish these two medicinal materials.

  4. The role of Phragmites in the CH4 and CO2 fluxes in a minerotrophic peatland in southwest Germany

    NASA Astrophysics Data System (ADS)

    van den Berg, Merit; Ingwersen, Joachim; Lamers, Marc; Streck, Thilo

    2016-11-01

    Peatlands are interesting as a carbon storage option, but are also natural emitters of the greenhouse gas methane (CH4). Phragmites peatlands are particularly interesting due to the global abundance of this wetland plant (Phragmites australis) and the highly efficient internal gas transport mechanism, which is called humidity-induced convection (HIC). The research aims were to (1) clarify how this plant-mediated gas transport influences the CH4 fluxes, (2) which other environmental variables influence the CO2 and CH4 fluxes, and (3) whether Phragmites peatlands are a net source or sink of greenhouse gases. CO2 and CH4 fluxes were measured with the eddy covariance technique within a Phragmites-dominated fen in southwest Germany. One year of flux data (March 2013-February 2014) shows very clear diurnal and seasonal patterns for both CO2 and CH4. The diurnal pattern of CH4 fluxes was only visible when living, green reed was present. In August the diurnal cycle of CH4 was the most distinct, with 11 times higher midday fluxes (15.7 mg CH4 m-2 h-1) than night fluxes (1.41 mg CH4 m-2 h-1). This diurnal cycle has the highest correlation with global radiation, which suggests a high influence of the plants on the CH4 flux. But if the cause were the HIC, it would be expected that relative humidity would correlate stronger with CH4 flux. Therefore, we conclude that in addition to HIC, at least one additional mechanism must be involved in the creation of the convective flow within the Phragmites plants. Overall, the fen was a sink for carbon and greenhouse gases in the measured year, with a total carbon uptake of 221 g C m-2 yr-1 (26 % of the total assimilated carbon). The net uptake of greenhouse gases was 52 g CO2 eq. m-2 yr-1, which is obtained from an uptake of CO2 of 894 g CO2 eq. m-2 yr-1 and a release of CH4 of 842 g CO2 eq. m-2 yr-1.

  5. Rhizome phyllosphere oxygenation in Phragmites and other species in relation to redox potential, convective gas flow, submergence and aeration pathways.

    PubMed

    Armstrong, J; Jones, R E; Armstrong, W

    2006-01-01

    Underground rhizomes of emergent aquatic macrophytes are important for perennation, vegetative spread, competition and anchorage. In four species we examined the potential for the development of oxidized phyllospheres around rhizome apical buds, similar to the protective oxygenated rhizospheres around roots. Redox potentials and polarographic measurements of radial oxygen loss were recorded using platinum cathodes around the apical buds. The aeration pathway from atmosphere to phyllosphere was investigated anatomically and by applied pressurized gas flow. Redox potentials increased by +400, +45, +200 and +340 mV around rhizome apices of Phragmites australis, Oryza rhizomatis, Carex rostrata and Glyceria maxima, respectively. Radial oxygen loss from rhizome apices of Phragmites was increased by convective gas flow through the rhizome and by shoot de-submergence, and decreased by resistances applied within the aeration pathway and by shoot submergence. We conclude that oxygen passes via internal gas-space connections between aerial shoot, rhizome and underground buds and into the phyllosphere regions via scale-leaf stomata and surfaces on the buds. We suggest that oxidized phyllospheres may protect rhizome apices against phytotoxins in waterlogged soils, just as oxidized rhizospheres protect roots.

  6. Aurora Australis as seen from STS-62

    NASA Technical Reports Server (NTRS)

    1994-01-01

    Aurora Australis or southern lights as seen from STS-62. The multi-hued shafts of light, extending upward to 200 miles above the Earth's surface, are caused by beams of energetic electrons colliding with the oxygen and nitrogen in the Earth's upper atmosphere.

  7. Antioxidative system and oxidative stress markers in wild populations of Erica australis L. differentially exposed to pyrite mining activities.

    PubMed

    Márquez-García, Belén; Córdoba, Francisco

    2009-11-01

    Erica australis L. is a widely distributed shrub able to grow in a variety of environments. In the Iberian Pyritic Belt (SW Spain and Portugal), E. australis can be observed growing successfully in very acidic and highly metal-enriched soils. However, no data about the metal tolerance of this plant in wild populations have been reported so far. In this study, we have analysed metal contents in the leaves of E. australis from three wild populations growing in soils affected by metals in different ways (mine wastes, the terrace of a river affected by acid mine drainage and soils not affected by mining activities but enriched in metals due the geology of the area) and, taking into account that metals may generate reactive oxygen species, we also assayed the oxidative damages and the antioxidative defences. All plants contained high levels of Fe and Mn in the leaves, but plants exposed to mining activities also accumulate different levels of As, Ni, Mo, Pb, and Zn depending on the population considered. Our data show that E. australis responds to metal-catalysed production of reactive radicals by oxidising ascorbic acid, which is present at concentrations much higher than described in other plant species, but it is highly oxidised, close to 40%. Ascorbic acid may counteract reactive oxygen species, and no cell damage was produced, as shown by the low levels of H(2)O(2) and lipid peroxidation found compared with other plant species and no damage reflected in pigment levels.

  8. Aurora Australis, Spiked, Sinuous Green Airglow

    NASA Technical Reports Server (NTRS)

    1991-01-01

    This distant view of the Aurora Australis or Southern Lights (location unknown) shows a spiked and sinuous band of green airglow above the Earth Limb. Calculated to be in the 80 - 120 km altitude region, auroral activity is due to exitation of atomic oxygen in the upper atmosphere by radiation from the van Allen Radiation Belts and is most common above the 65 degree north and south latitude range during the spring and fall of the year.

  9. WATERSHED LAND USE INFLUENCES NUTRIENT CONCENTRATIONS OF PHRAGMITES AUSTRALIS LEAVES IN SUBESTUARIES OF CHESAPEAKE BAY. (R828684C001)

    EPA Science Inventory

    The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Concl...

  10. Simulation of the Effect of Artificial Water Transfer on Carbon Stock of Phragmites australis in the Baiyangdian Wetland, China.

    PubMed

    Chen, Xinyong; Wang, Fengyi; Lu, Jianjian; Li, Hongbo; Zhu, Jing; Lv, Xiaotong

    2017-01-01

    How to explain the effect of seasonal water transfer on the carbon stocks of Baiyangdian wetland is studied. The ecological model of the relationship between the carbon stocks and water depth fluctuation of the reed was established by using STELLA software. For the first time the Michaelis-Menten equation (1) introduced the relation function between the water depth and reed environmental carrying capacity, (2) introduced the concept of suitable growth water depth, and (3) simulated the variation rules of water and reed carbon stocks of artificial adjustment. The model could be used to carry out the research on the optimization design of the ecological service function of the damaged wetland.

  11. Simulation of the Effect of Artificial Water Transfer on Carbon Stock of Phragmites australis in the Baiyangdian Wetland, China

    PubMed Central

    Chen, Xinyong; Wang, Fengyi; Li, Hongbo; Zhu, Jing; Lv, Xiaotong

    2017-01-01

    How to explain the effect of seasonal water transfer on the carbon stocks of Baiyangdian wetland is studied. The ecological model of the relationship between the carbon stocks and water depth fluctuation of the reed was established by using STELLA software. For the first time the Michaelis-Menten equation (1) introduced the relation function between the water depth and reed environmental carrying capacity, (2) introduced the concept of suitable growth water depth, and (3) simulated the variation rules of water and reed carbon stocks of artificial adjustment. The model could be used to carry out the research on the optimization design of the ecological service function of the damaged wetland. PMID:28348922

  12. Supplemental Enviromnentul Assessment for Control of Common Reed (Phragmites australis) at Joint Base Langley-Eustis, Fort Eustis, Virginia

    DTIC Science & Technology

    2012-09-01

    occur on the periphery of the Main Post such as wetlands bordering Taylor Avenue across from Eustis Lake and along portions of the Wmwick River...sites. These sources include Skiffcs Creek, Eustis r.ake, and the Warwick River. Eu.~tis Lake is a 45-acrc man-made recreational lake used for... laking no action, common reed will continue to expand ami degrade more wellands. This could include the planned Spar/ina marsh being created to

  13. Dynamics of the dayside Aurora Australis

    NASA Astrophysics Data System (ADS)

    McEwen, D. J.; Sivjee, G. G.; Azeem, S. I.

    2010-01-01

    Current dayside optical studies of Aurora Australis from the Amundsen-Scott Research Station at the South Pole (74 degrees magnetic latitude) show some striking differences from optical results reported from Svalbard. A 6-channel meridian scanning photometer operating during the past three austral winters shows, in particular, the 630 nm emission is much lower, on average, than the Arctic dayside aurora and very weak on some days. The 558 nm intensity is higher relative to 630 nm suggesting the incoming electrons have a higher average energy. There are notable differences in auroral forms, giving further evidence of asymmetries in the two dayside ovals.

  14. Phytotoxicity of chlorinated benzenes to Typha angustifolia and Phragmites communis.

    PubMed

    Ma, Xingmao; Havelka, Megan M

    2009-02-01

    Healthy growth of plants is a prerequisite for successful application of phytoremediation technologies. Typha angustifolia and Phragmites communis are common wetland plants and have shown potential for phytoremediation of hexachlorobenzene (HCB). However, the lack of phytotoxicity data impedes their application in field sites. This study investigated the phytotoxicity of HCB, and its two metabolites: 1,3,5-trichlorobenzene (1,3,5-TCB) and 1,4-dichlorobenzene (1,4-DCB) to Typha and the phytotoxicity of 1,3,5-TCB to Phragmites. The phytotoxicity of 1,3,5-TCB is species-dependent, with Typha demonstrating significantly higher tolerance than Phragmites. The concentration of 1,3,5-TCB causing zero growth of Phragmites was determined to be 1575 mg TCB/kg dry sediment. The concentration has to be doubled to completely inhibit the growth of Typha. Adverse effects of chlorinated benzenes in sediments on Typha increased with decreasing chlorine atoms. The concentrations causing zero growth of Typha are 5765 mg HCB/kg dry soil, 3157 mg 1,3,5-TCB/kg dry soil, and 1325 mg 1,4-DCB/kg dry soil. The higher toxicity of 1,4-DCB than 1,3,5-TCB and HCB in sediment was ascribed to its higher availability and easiness to be taken up by plants. The conclusion was supported by both growth rate calculations and plant height measurements. (c) 2008 Wiley Periodicals, Inc. Environ Toxicol, 2009.

  15. R Coronae Australis: A Cosmic Watercolour

    NASA Astrophysics Data System (ADS)

    2010-06-01

    This magnificent view of the region around the star R Coronae Australis was created from images taken with the Wide Field Imager (WFI) at ESO's La Silla Observatory in Chile. R Coronae Australis lies at the heart of a nearby star-forming region and is surrounded by a delicate bluish reflection nebula embedded in a huge dust cloud. The image reveals surprising new details in this dramatic area of sky. The star R Coronae Australis lies in one of the nearest and most spectacular star-forming regions. This portrait was taken by the Wide Field Imager (WFI) on the MPG/ESO 2.2-metre telescope at the La Silla Observatory in Chile. The image is a combination of twelve separate pictures taken through red, green and blue filters. This image shows a section of sky that spans roughly the width of the full Moon. This is equivalent to about four light-years at the distance of the nebula, which is located some 420 light-years away in the small constellation of Corona Australis (the Southern Crown). The complex is named after the star R Coronae Australis, which lies at the centre of the image. It is one of several stars in this region that belong to the class of very young stars that vary in brightness and are still surrounded by the clouds of gas and dust from which they formed. The intense radiation given off by these hot young stars interacts with the gas surrounding them and is either reflected or re-emitted at a different wavelength. These complex processes, determined by the physics of the interstellar medium and the properties of the stars, are responsible for the magnificent colours of nebulae. The light blue nebulosity seen in this picture is mostly due to the reflection of starlight off small dust particles. The young stars in the R Coronae Australis complex are similar in mass to the Sun and do not emit enough ultraviolet light to ionise a substantial fraction of the surrounding hydrogen. This means that the cloud does not glow with the characteristic red colour seen in

  16. Transplantation as a method for restoring the seagrass Posidonia australis

    NASA Astrophysics Data System (ADS)

    Bastyan, G. R.; Cambridge, M. L.

    2008-08-01

    Transplant trials of the seagrass Posidonia australis were carried out after loss of seagrasses following eutrophication and increased turbidity in two marine inlets on the south coast of Western Australia. A pilot study in Oyster Harbour measured survival and growth in situ for 4 years. Long-term survival rates were high (96-98%), providing plants were anchored into the sediment. All unanchored plants were lost in the first winter. Following the success of the pilot study, a more comprehensive program began 3 years later with over 500 transplant units collected from either actively growing edges of nearby patches (plagiotropic growth form) or within established meadows (orthotropic growth form). Transplant units from edges expanded at a faster rate compared to units from mid-meadow but increases in shoot numbers were similar. Growth rates in the first 2.5 years averaged 10-20 cm yr -1 horizontal rhizome extension, depending on the source of the transplant units, and 4-12 shoots per initial shoot yr -1, depending on the initial shoot number of the transplant unit. After 5 years, shoot numbers of individual transplants were similar to shoot densities recorded for natural meadows, >500 shoots m -2. Approximately, 10% of transplants from mid-meadow flowered in the first year, whereas transplants from edges flowered only after 5 years. Transplant trials were also established in nearby Princess Royal Harbour at a site selected to test the effect of disturbance by bioturbation from large sand-burrowing worms or by sediment erosion. Survival was lower than in Oyster Harbour, 75-89% in areas with bioturbation but only 14% in areas where sediments were eroded. Growth was poor, <1-2 shoots per shoot yr -1 with high shoot mortality, and low rates of increase in rhizome length, <5 cm yr -1. In areas affected by worm bioturbation, there was almost no horizontal expansion of plants because rhizomes grew vertically to keep pace with sediment deposition. This study showed that

  17. Rickettsia australis Activates Inflammasome in Human and Murine Macrophages

    PubMed Central

    Smalley, Claire; Bechelli, Jeremy; Rockx-Brouwer, Dedeke; Saito, Tais; Azar, Sasha R.; Ismail, Nahed; Walker, David H.; Fang, Rong

    2016-01-01

    Rickettsiae actively escape from vacuoles and replicate free in the cytoplasm of host cells, where inflammasomes survey the invading pathogens. In the present study, we investigated the interactions of Rickettsia australis with the inflammasome in both mouse and human macrophages. R. australis induced a significant level of IL-1β secretion by human macrophages, which was significantly reduced upon treatment with an inhibitor of caspase-1 compared to untreated controls, suggesting caspase-1-dependent inflammasome activation. Rickettsia induced significant secretion of IL-1β and IL-18 in vitro by infected mouse bone marrow-derived macrophages (BMMs) as early as 8–12 h post infection (p.i.) in a dose-dependent manner. Secretion of these cytokines was accompanied by cleavage of caspase-1 and was completely abrogated in BMMs deficient in caspase-1/caspase-11 or apoptosis-associated speck-like protein containing a caspase activation and recruitment domain (ASC), suggesting that R. australis activate the ASC-dependent inflammasome. Interestingly, in response to the same quantity of rickettsiae, NLRP3-/- BMMs significantly reduced the secretion level of IL-1β compared to wild type (WT) controls, suggesting that NLRP3 inflammasome contributes to cytosolic recognition of R. australis in vitro. Rickettsial load in spleen, but not liver and lung, of R. australis-infected NLRP3-/- mice was significantly greater compared to WT mice. These data suggest that NLRP3 inflammasome plays a role in host control of bacteria in vivo in a tissue-specific manner. Taken together, our data, for the first time, illustrate the activation of ASC-dependent inflammasome by R. australis in macrophages in which NLRP3 is involved. PMID:27362650

  18. BOOK REVIEW: European Perceptions of Terra Australis

    NASA Astrophysics Data System (ADS)

    Sterken, Christiaan

    2012-12-01

    Terra Australis - the southern land - has been one of the most widespread concepts in European geography from the sixteenth to the eighteenth century. This book comprises a set of 14 interdisciplinary scholarly contributions that deal with personal perceptions of Terra Australis by cartographers and explorers, and with putting these perceptions in their historical and cultural environments. This book seems, at a first glance, to be very remote from astronomy - and even from the history of astronomy - however, as it also offers an excellent background to Captain James Cook's second voyage to observe the 1769 transit of Venus from Tahiti, it definitely is a work of truly interdisciplinary character. Cook's voyages, in fact, became a model in which key scientists of many nationalities and disciplines traveled together on ships. In these voyages, art, science, technology and political power were centralised and united. The chapters range across history, the visual arts, literature, popular culture, technology, politics and science. Issues of scientific reasoning are raised in the description of how people did think about the south before there even existed a perception of the unknown land - quite comparable to how ancient and early-modern astronomers had their thought about cosmology even before any observational data were available. Several early map systems - like the zonal and T-O maps (medieval world maps with the letter T inside an O representing the lands inside a circle of oceans) - are described, and the description of Roman geography shows the amazing fact that theory and practice were not unified, and existed independently of each other insofar that a real paradox between theory and observation had persisted for a very long time. The maps and charts also exemplify the long-lasting consequences of early modern copy-paste practice: navigators copied original sketch charts of coasts that were previously unknown to them, herewith committing many translation and

  19. Morphology of the eye of the southern right whales (Eubalaena australis).

    PubMed

    Buono, Mónica R; Fernández, Marta S; Herrera, Yanina

    2012-02-01

    Recently, there has been a growing interest in the anatomy and optics of the visual system of cetaceans. However, much of the new information has been focused on odontocetes, and relatively little is known about the visual anatomy of baleen whales. The aim of this study was describe the eye anatomy of the southern right whale (Eubalaena australis). Eye samples were collected from 26 calves, four adults with known body length, as well as two specimens of unknown body length that had stranded near their nursery ground at Península Valdés, Argentina, over 6 years. We provide anatomical descriptions of the eyeball and extraocular structures, as well as quantitative data in the form of eyeball, corneal, scleral, and lens measurements. To explore the sensitivity of the eye to light, the f-number was estimated in one specimen. We found that the eyes of the calves differed from those of the adults in having less periorbital fat surrounding the eyeball. We also observed variations in the abundance of periorbital fat among the adult specimens. The regression analysis revealed a correlation between body length and eyeball size. By contrast, the dimensions of the cornea were only weakly correlated with body length. The estimated f-number suggests that the optical sensitivity of the Eubalaena australis eye is relatively low. However, caution had to be taken in interpreting f-number as a proxy of eye sensitivity because it depends on the lens size, which can be affected by the fixation methods used.

  20. Promoting species establishment in a phragmites-dominated great lakes coastal wetland

    USGS Publications Warehouse

    Carlson, M.L.; Kowalski, K.P.; Wilcox, D.A.

    2009-01-01

    This study examined efforts to promote species establishment and maintain diversity in a Phragmites-dominated wetland where primary control measures were underway. A treatment experiment was performed at Crane Creek, a drowned-river-mouth wetland in Ottawa National Wildlife Refuge along the shore of western Lake Erie. Following initial aerial spraying of Phragmites with glyphosate, this study tested combinations of cutting, raking, and additional hand spraying of Phragmites with glyphosate as methods to promote growth of other wetland species and increase plant diversity. Percent-cover vegetation data were collected in permanent plots before and after treatments, and follow-up sampling was performed the following year. Increased species richness, species emergence, and relative dominance of non-Phragmites taxa were used as measures of treatment success. We also examined treatment effects on Phragmites cover. Dimensionality of seedbank and soil properties was reduced using principal component analysis. With the exception of nitrogen, soil nutrients affected species establishment, non-Phragmites taxa dominance, and Phragmites cover. A more viable seedbank led to greater species emergence. Treatments had differential effects on diversity depending on elevation and resulting degree of hydrologic inundation. Whereas raking to remove dead Phragmites biomass was central to promoting species establishment in dry areas, spraying had a greater impact in continually inundated areas. For treatment success across elevations into the year following treatments, spraying in combination with cutting and raking had the greatest effect. The results of this study suggest that secondary treatments can produce a short-term benefit to the plant community in areas treated for Phragmites.

  1. Aurora Australis, Spiked and Sinuous Red and Green Airglow

    NASA Technical Reports Server (NTRS)

    1991-01-01

    This view of the Aurora Australis or Southern Lights, in the 80 - 120 km altitude region, (location unknown) shows a spiked and sinuous band of red and green airglow above the Earth Limb and a charged plasma glow around the orbiter. Auroral activity is due to exitation of atomic oxygen in the upper atmosphere by the van Allen Radiation Belts and is most common above the 65 degree north and south latitude range during the spring and fall of the year.

  2. Aurora Australis, Spiked and Sinuous Red and Green Airglow

    NASA Technical Reports Server (NTRS)

    1991-01-01

    In This distant view of the Aurora Australis or Southern Lights (location unknown), a spiked and sinuous band of red and green airglow above the Earth Limb is highlighted by moonglow. Auroral activity is due to exitation of atomic oxygen in the upper atmosphere by radiation from the van Allen Radiation Belts and is most common above the 65 degree north and south latitude range during the spring and fall of the year.

  3. The presence of eucalyptol in Artemisia australis validates its use in traditional Hawaiian medicine

    PubMed Central

    Zant, David; Gubler, Daniel A.

    2014-01-01

    Objective To identify the major organic compounds of Artemisia australis (A. australis), a plant used in traditional Hawaiian medicine for the treatment of asthma. Methods The dichloromethane extract of A. australis was analyzed by gas chromatography-mass spectroscopy and major compounds were identified by a National Institute of Standards and Technology library search and confirmed by peak enhancement. Results The major chemical components of A. australis include eucalyptol, borneol, and caryophyllene. Conclusions The presence and biological activity of eucalyptol correlate very well with the usage of this plant in traditional Hawaiian medicine. PMID:25183270

  4. The parasitic plant Cuscuta australis is highly insensitive to abscisic acid-induced suppression of hypocotyl elongation and seed germination.

    PubMed

    Li, Juan; Hettenhausen, Christian; Sun, Guiling; Zhuang, Huifu; Li, Jian-Hong; Wu, Jianqiang

    2015-01-01

    Around 1% of angiosperms are parasitic plants. Their growth and development solely or partly depend on host plants from which they extract water, nutrients, and other molecules using a parasitic plant-specific organ, the haustorium. Strong depletion of nutrients can result in serious growth retardation and in some cases, death of the hosts. The genus Cuscuta (dodder) comprises about 200 holoparasitic species occurring on all continents. Their seedlings have no roots and cotyledons but are only string-like hypocotyls. When they contact suitable host plants, haustoria are formed and thereafter seedlings rapidly develop into vigorously growing branches without roots and leaves. This highly specialized lifestyle suggests that Cuscuta plants likely have unique physiology in development and stress responses. Using germination and seedling growth assays, we show that C. australis seeds and seedlings are highly insensitive to abscisic acid (ABA). Transcriptome analysis and protein sequence alignment with Arabidopsis, tomato, and rice homologs revealed that C. australis most likely consists of only four functional ABA receptors. Given that Cuscuta plants are no longer severely challenged by drought stress, we hypothesize that the ABA-mediated drought resistance pathway in Cuscuta spp. might have had degenerated over time during evolution.

  5. Global climate drives southern right whale (Eubalaena australis) population dynamics.

    PubMed

    Leaper, Russell; Cooke, Justin; Trathan, Phil; Reid, Keith; Rowntree, Victoria; Payne, Roger

    2006-06-22

    Sea surface temperature (SST) time-series from the southwest Atlantic and the El Niño 4 region in the western Pacific were compared to an index of annual calving success of the southern right whale (Eubalaena australis) breeding in Argentina. There was a strong relationship between right whale calving output and SST anomalies at South Georgia in the autumn of the previous year and also with mean El Niño 4 SST anomalies delayed by 6 years. These results extend similar observations from other krill predators and show clear linkages between global climate signals and the biological processes affecting whale population dynamics.

  6. Crystal growing

    NASA Technical Reports Server (NTRS)

    Neville, J. P.

    1990-01-01

    One objective is to demonstrate the way crystals grow and how they affect the behavior of material. Another objective is to compare the growth of crystals in metals and nonmetals. The procedures, which involve a supersaturated solution of a salt that will separate into crystals on cooling and the pouring off of an eutectic solution to expose the crystals formed by a solid solution when an alloy of two metals forms a solid and eutectic solution on cooling, are described.

  7. Effect of Phragmites japonicus harvest frequency and timing on dry matter yield and nutritive value.

    PubMed

    Tanaka, Takashi S T; Irbis, Chagan; Kumagai, Hajime; Wang, Pengyun; Li, Kunzhi; Inamura, Tatsuya

    2017-02-01

    Phragmites is a cosmopolitan perennial emergent macrophyte that is distributed worldwide. In recent years, Phragmites has attracted attention for its potential use as roughage. Given the increasing demand for feed and the number of constructed wetlands (CWs) vegetated with Phragmites, Phragmites is expected to play an important role in roughage production. Thus, it is vital to understand the effects of harvest timing and frequency on dry matter yield, nutritive value, and nitrogen (N) removal to establish appropriate vegetation management. In two CWs in Southwest China, four treatments with different harvesting frequencies were evaluated in monospecific areas of P. japonicus. The four treatments included no harvest, single harvest at 6 months, two harvests at 2 and 4 months, and three harvests at 2, 4, and 6 months. A sharp decline in the total digestible nutrients (TDN) concentration and the rate of increase in dry matter (DM) yield was associated with the heading timings, and the seasonal variations in TDN were likely influenced by carbohydrate accumulation in the stems. The three harvest treatment contributed to substantially improve the N and DM yields without decreasing the nutritive value but negatively affected the growth in the following year. Therefore, not only the combinations of harvest timing and frequency but also other management practices, including partial harvesting, may be needed to optimize CW performance and roughage production.

  8. Effects of high salinity from desalination brine on growth, photosynthesis, water relations and osmolyte concentrations of seagrass Posidonia australis.

    PubMed

    Cambridge, M L; Zavala-Perez, A; Cawthray, G R; Mondon, J; Kendrick, G A

    2017-02-15

    Highly saline brines from desalination plants expose seagrass communities to salt stress. We examined effects of raised salinity (46 and 54psu) compared with seawater controls (37psu) over 6weeks on the seagrass, Posidonia australis, growing in tanks with the aim of separating effects of salinity from other potentially deleterious components of brine and determining appropriate bioindicators. Plants survived exposures of 2-4weeks at 54psu, the maximum salinity of brine released from a nearby desalination plant. Salinity significantly reduced maximum quantum yield of PSII (chlorophyll a fluorescence emissions). Leaf water potential (Ψw) and osmotic potential (Ψπ) were more negative at increased salinity, while turgor pressure (Ψp) was unaffected. Leaf concentrations of K(+) and Ca(2+) decreased, whereas concentrations of sugars (mainly sucrose) and amino acids increased. We recommend leaf osmolarity, ion, sugar and amino acid concentrations as bioindicators for salinity effects, associated with brine released in desalination plant outfalls.

  9. Functional validation of Phragmites communis glutathione reductase (PhaGR) as an essential enzyme in salt tolerance.

    PubMed

    Zhang, Xia; Quan, Geng; Wang, Jing; Han, Huiling; Chen, ShiHua; Guo, ShanLi; Yin, HaiBo

    2015-04-01

    Reed plants (Phragmites communis (Linn.) Trin) are hydrophilic perennial grasses growing in fresh and brackish waters. These plants readily adapt to arid and high salinity conditions; however, their resistance mechanism against abiotic stresses, especially high salinity, is largely unknown. In the present study, we cloned a glutathione reductase gene from P. communis and investigated its role in conferring salt tolerance in reed plants. The expression of PhaGR at the transcriptional level was affected by multiple abiotic stresses including NaCl, Cd(2+), heat, cold, PEG 6000, and abscisic acid (ABA). Furthermore, NaCl and Cd(2+) could increase its expressions at the translational level. NaCl and Cd(2+) also increased the biosynthesis of soluble protein and reduced glutathione (GSH). Reed seedlings that were challenged with NaCl showed higher levels of GR activities, which corroborated our gene expression data. The increase in GR possibly increased the salt tolerance of reed plants through GSH production. Thus, PhaGR is a potential target gene in improving the salt tolerance of crops through genetic manipulation.

  10. Exogenous melatonin affects photosynthesis in characeae Chara australis

    PubMed Central

    Lazár, Dušan; Murch, Susan J.; Beilby, Mary J.; Al Khazaaly, Sabah

    2013-01-01

    Melatonin was found in the fresh water characeae Chara australis. The concentrations (~4 μg/g of tissue) were similar in photosynthesizing cells, independent of their position on the plant and rhizoids (roots) without chloroplasts. Exogenous melatonin, added at 10 μM to the artificial pond water, increased quantum yield of photochemistry of photosystem II by 34%. The increased efficiency appears to be due to the amount of open reaction centers of photosystem II, rather than increased efficiency of each reaction center. More open reaction centers reflect better functionality of all photosynthetic transport chain constituents. We suggest that melatonin protection against reactive oxygen species covers not only chlorophyll, but also photosynthetic proteins in general. PMID:23299331

  11. Mangrovibacter phragmitis sp. nov., an endophyte isolated from the roots of Phragmites karka.

    PubMed

    Behera, Pratiksha; Ramana, V Venkata; Maharana, Bhagirathi; Joseph, Neetha; Vaishampayan, Parag; Singh, Nitin; Shouche, Yogesh; Bhadury, Punyasloke; Mishra, Samir R; Raina, Vishakha; Suar, Mrutyunjay; Pattnaik, Ajit K; Rastogi, Gurdeep

    2017-01-12

    A facultative anaerobic, Gram-stain-negative, rod-shaped, nitrogen fixing, endophytic bacterial strain MP23T was isolated from the roots of Phragmites karka growing in Chilika Lagoon, Odisha, India. Strain MP23T was slightly halophilic and optimal NaCl concentration and temperature for growth was 1% and 30°C, respectively. On the basis of 16S rRNA gene sequence similarities, strain MP23T was affiliated to family Enterobacteriaceae and most closely related to Mangrovibacter yixingensis KCTC 42181T and Mangrovibacter plantisponsor DSM 19579T by 99.71%, followed by Salmonella enterica subsp. salamae DSM 9220T (97.22%), Cronobacter condimenti LMG 26250T (97.14%), and Salmonella enterica subsp. diarizone DSM 14847T (97%). Sequence analysis of 16S rRNA, hsp60, gyrB, and rpoB genes showed that strain MP23T formed a phylogenetic cluster with Mangrovibacter yixingensis KCTC 42181T and Mangrovibacter plantisponsor DSM 19579T indicating that it belong to genus Mangrovibacter. The major cellular fatty acids were C16:0, C18:1ω6c and/or C18:1ω7c, C16:1ω6c and/or C16:1ω7c, C14:0, C14:03OH and/or C16:1isoI, and C17:0cyclo. Polar lipid pattern of strain MP23T consisted of phosphatidylglycerol, diphosphatidylglycerol, phosphatidylethanolamine. The DNA G+C content was 50.3 mol%. Based on experimental DNA-DNA hybridization values and average nucleotide identity derived from in silico comparison of whole genome sequences, strain MP23T could be distinguished from its closest neighbours. We therefore conclude that strain MP23T represents a novel species of the genus Mangrovibacter for which the name Mangrovibacter phragmitis sp. nov. is proposed. The type strain is MP23T (= DSM 100250 T = KCTC 42580 T).

  12. Moon phase influences the diet of southern Ray's bream Brama australis.

    PubMed

    Horn, P L; Forman, J S; Dunn, M R

    2013-04-01

    Diet composition of the southern Ray's bream Brama australis was examined from stomach contents of 399 specimens sampled by bottom trawl on Chatham Rise to the east of South Island, New Zealand, over 3 years. Prey items were predominantly mesopelagic fishes and crustaceans. Multivariate analysis indicated that moon phase explained more of the diet variability than any other predictor examined. It appears likely that diet composition is influenced by a combination of changes in both tidal flows and illumination. Different combinations of prey were consumed by B. australis at different times of the lunar cycle. An influence of moon phase on feeding by fishes has rarely been reported, but it is likely that moon phase influences the diets of other species that specialize in mesopelagic prey. The most important prey group by mass for B. australis was Myctophidae (primarily Lampanyctodes hectoris), followed by Stomiiformes (primarily Maurolicus australis) and shrimps (Sergestes spp). An ontogenetic shift in diet was observed, from numerical dominance by small crustaceans including amphipods and euphausiids (with some fishes) in smaller (mass <1045 g) B. australis to pelagic teleost prey (with a few larger crustaceans) in larger (>1440 g) B. australis.

  13. Reproduction at the extremes: pseudovivipary, hybridization and genetic mosaicism in Posidonia australis (Posidoniaceae)

    PubMed Central

    Sinclair, Elizabeth A.; Statton, John; Hovey, Renae; Anthony, Janet M.; Dixon, Kingsley W.; Kendrick, Gary A.

    2016-01-01

    Background and Aims Organisms occupying the edges of natural geographical ranges usually survive at the extreme limits of their innate physiological tolerances. Extreme and prolonged fluctuations in environmental conditions, often associated with climate change and exacerbated at species’ geographical range edges, are known to trigger alternative responses in reproduction. This study reports the first observations of adventitious inflorescence-derived plantlet formation in the marine angiosperm Posidonia australis, growing at the northern range edge (upper thermal and salinity tolerance) in Shark Bay, Western Australia. These novel plantlets are described and a combination of microsatellite DNA markers and flow cytometry is used to determine their origin. Methods Polymorphic microsatellite DNA markers were used to generate multilocus genotypes to determine the origin of the adventitious inflorescence-derived plantlets. Ploidy and genome size were estimated using flow cytometry. Key Results All adventitious plantlets were genetically identical to the maternal plant and were therefore the product of a novel pseudoviviparous reproductive event. It was found that 87 % of the multilocus genotypes contained three alleles in at least one locus. Ploidy was identical in all sampled plants. The genome size (2 C value) for samples from Shark Bay and from a separate site much further south was not significantly different, implying they are the same ploidy level and ruling out a complete genome duplication (polyploidy). Conclusions Survival at range edges often sees the development of novel responses in the struggle for survival and reproduction. This study documents a physiological response at the trailing edge, whereby reproductive strategy can adapt to fluctuating conditions and suggests that the lower-than-usual water temperature triggered unfertilized inflorescences to ‘switch’ to growing plantlets that were adventitious clones of their maternal parent. This may

  14. Epidermal ultrastructure of the southern right whale calf (Eubalaena australis).

    PubMed

    Pfeiffer, C J; Rowntree, V J

    1996-04-01

    An ultrastructural analysis by transmission and scanning electron microscopy was carried out on normal epidermis of six southern right whale (Eubalaena australis) calves which stranded over a period of several months at Peninsula Valdes, Argentina. This was undertaken to 1) provide the first normal skin ultrastructural data on this highly endangered species which is known to display skin pathology in some instances, and 2) to elucidate further the integumentary specializations which have developed in diving marine mammals. Southern right whale lipokeratinocytes demonstrated parakeratosis and numerous intracellular lipid bodies, keratin and melanosomes, as reported for other cetacean species, but showed several unique ultrastructural features as well. These included a high prevalence of intranuclear inclusion bodies resembling small fragments of cytoplasmic keratin, and close structural relationship between cytoplasmic lipid droplets and the nucleus. The subcellular morphology supported the concept of possible nuclear import of cytoplasmic keratin and lipid metabolites through enlargements of the nuclear pore complex or other disruptions of the nuclear envelope. The light microscopy and scanning electron microscopy also revealed an irregular contour of the lipokeratinocytes which comprised the thick stratum externum, and surface flaking of the outermost cells which were covered by stubby microvillous-like remnants of intercellular junctions. These results thus suggest that the long-tem aquatic evolution of this cetacean species has resulted in a number of integumentary specializations and that investigation of their submicroscopic cytology may help elucidate the general cell biology of nuclear-cytoplasmic interactions.

  15. Comparative Hepatoprotective Activity of Ethanolic Extracts of Cuscuta australis against Acetaminophen Intoxication in Wistar Rats

    PubMed Central

    Folarin, Rachael O.; Omirinde, Jamiu O.; Bejide, Ronald; Isola, Tajudeen O.; Usende, Levi I.; Basiru, Afisu

    2014-01-01

    This study investigates the comparative hepatoprotective activity of crude ethanol extracts of Cuscuta australis against acetaminophen (APAP) intoxication. Thirty-six rats were randomly divided into six groups of 6 replicates: Group 1 which served as control received water. Group 2 was orally administered 835 mg/kg body wt. of paracetamol on day 8. Groups 3 and 4 were orally administered ethanolic extracts of the seed of Cuscuta australis in doses of 125 mg/kg and 250 mg/kg, respectively, for 7 days and then intoxicated as in Group 2 on the 8th day. Groups 5 and 6 received similar oral doses of Cuscuta australis stem extracts for 7 days and then intoxicated as in Groups 3 and 4. Group 2 rats showed severe periportal hepatic necrosis, significantly elevated serum hepatic injury markers, markedly increased lipid peroxidation, and decreased hepatic antioxidant enzymes activities. Remarkably, Cuscuta australis (seed and stem) extract pretreatments in Groups 3, 4, 5, and 6, most especially, the stem extract pretreatment in Groups 5 and 6, improved better the hepatic histoarchitecture, the hepatocellular, and the oxidative stress injury markers in a dose-dependent manner. Conclusively, ethanol extractions of Cuscuta australis stem appear to protect the liver from acetaminophen intoxication better than the seed counterpart. PMID:27433518

  16. Implications of polyploidy events on the phenotype, microstructure, and proteome of Paulownia australis

    PubMed Central

    Zhai, Xiaoqiao; Deng, Minjie; Zhao, Zhenli; Liu, Wenshan; Cao, Yabing

    2017-01-01

    Polyploidy events are believed to be responsible for increasing the size of plant organs and enhancing tolerance to environmental stresses. Autotetraploid Paulownia australis plants exhibit superior traits compared with their diploid progenitors. Although some transcriptomics studies have been performed and some relevant genes have been revealed, the molecular and biological mechanisms regulating the predominant characteristics and the effects of polyploidy events on P. australis remain unknown. In this study, we compared the phenotypes, microstructures, and proteomes of autotetraploid and diploid P. australis plants. Compared with the diploid plant, the leaves of the autotetraploid plant were longer and wider, and the upper epidermis, lower epidermis, and palisade layer of the leaves were thicker, the leaf spongy parenchyma layer was thinner, the leaf cell size was bigger, and cell number was lower. In the proteome analysis, 3,010 proteins were identified and quantified, including 773 differentially abundant proteins. These results may help to characterize the P. australis proteome profile. Differentially abundant proteins related to cell division, glutathione metabolism, and the synthesis of cellulose, chlorophyll, and lignin were more abundant in the autotetraploid plants. These results will help to enhance the understanding of variations caused by polyploidy events in P. australis. The quantitative real-time PCR results provided details regarding the expression patterns of the proteins at mRNA level. We observed a limited correlation between transcript and protein levels. These observations may help to clarify the molecular basis for the predominant autotetraploid characteristics and be useful for plant breeding in the future. PMID:28273106

  17. Description of the Immature Stages of the Planthopper Lacertinella australis (Hemiptera: Delphacidae)

    PubMed Central

    Batiz, M. F. Rossi; Lenicov, A. M. Marino de Remes

    2014-01-01

    The five immature stages of the planthopper Lacertinella australis (Remes Lenicov and Rossi Batiz) (Hemiptera: Delphacidae: Saccharosydnini) are described and illustrated. The main characters that allowed us to distinguish the various stages were body size, number of tarsomeres and metatibial spines, and number of teeth on the spur. New biological data based on laboratory rearing and field observations showed that L. australis can carry out its biological cycle successfully on the graminaceous pampas grass (Cortaderia spp. Stapf (Poales: Poaceae)). In addition, the efficient rearing in captivity, the high survivorship registered, and overwintering only on this host plant suggests that L. australis is a potential biocontrol agent of this invasive graminaceous weed. This study provides information about the immature stages, including a key for their identification, based on laboratory reared specimens and field observations. PMID:25199992

  18. First artificial hybrid of the eel species Anguilla australis and Anguilla anguilla

    PubMed Central

    2011-01-01

    Background Studies on artificial hybridization of different Anguilla species were conducted recently, i.e. female A. australis with male A. dieffenbachii, and female A. japonica with male A. anguilla. The existence of these artificial hybrids was however not demonstrated by independent genetic methods. Two species - A. anguilla and A. australis - that are phylogenetically close but have different sexual maturation times (12-25 weeks and 6-8 weeks, respectively), were expected to produce favourable hybrids for reproduction studies. Results A modification of the protocol for the reproduction of Anguilla japonica was used to produce eight-day Anguilla australis larvae, with a success rate of 71.4%. Thus ten out of 14 females produced eggs that could be fertilized, and three batches resulted in mass hatching. Hybrid larvae from female A. australis x male A. Anguilla survived for up to seven days post fertilization (dpf). The early development of the hybrid showed typical characteristics of A. anguilla tail pigmentation at 50 hours post fertilization (hpf), indicating expression of genes derived from the father. Conclusions In this paper we describe the first production of hybrid larvae from male A. anguilla and female A. australis and their survival for up to 7 dpf. A species-specific nucleotide difference in the 18 S rDNA gene confirmed that genes from both A. australis and A. anguilla were present in the hybrids. The developmental stages of the hybrid eel embryos and larvae are described using high resolution images. Video footage also indicated a heart beat in 5-dpf larva. PMID:21396126

  19. Structure of the integument of southern right whales, Eubalaena australis.

    PubMed

    Reeb, Desray; Best, Peter Barrington; Kidson, Susan Hillary

    2007-06-01

    Skin (integument) anatomy reflects adaptations to particular environments. It is hypothesized that cetacean (whale) integument will show unique anatomical adaptations to an aquatic environment, particularly regarding differences in temperature, density, and pressure. In this study, the gross and histological structure of the southern right whale integument is described and compared with terrestrial mammals and previous descriptions of mysticete (baleen whale) and odontocete (toothed whale) species. Samples were taken of the integument of 98 free-swimming southern right whales, Eubalaena australis, and examined by both light and electron microscopy. Results show that three epidermal layers are present, with the stratum corneum being parakeratotic in nature. As in bowhead whales, southern right whales possess an acanthotic epidermis and a notably thick hypodermis, with epidermal rods and extensive papillomatosis. However, unlike bowhead whales, southern right whales possess an uninterrupted hypodermal layer. Surprisingly, the integument of balaenids (right and bowhead mysticetes) in general is more like that of odontocetes than that of the more closely related balaenopterids (rorqual mysticetes). Similarities to odontocetes were found specifically in the collagen fibers in a fat-free zone of the reticular dermal layer and the elastic fibers in the dermal and hypodermal layers. Callosities, a distinctive feature of this genus, have a slightly thicker stratum corneum and are usually associated with hairs that have innervated and vascularized follicles. These hairs may function as vibrissae, thus aiding in aquatic foraging by allowing rapid detection of changes in prey density. Although the thick insulatory integument makes right whales bulky and slow-moving, it is an adaptation for living in cold water. Epidermal thickness, presence of epidermal rods, and callosities may act as barriers against mechanical injury from bodily contact with conspecifics or hard surfaces in

  20. Community structure and in situ activity of nitrifying bacteria in Phragmites root-associated biofilms.

    PubMed

    Okabe, Satoshi; Nakamura, Yoshiyuki; Satoh, Hisashi

    2012-01-01

    The amount of oxygen released by Phragmites roots and the community structure and in situ activity of nitrifying bacteria in the root biofilms were analyzed by the combined use of 16S rRNA gene-cloning analysis, quantitative PCR (qPCR) assay and microelectrodes. Axial and radial O₂ microprofiles were obtained for individual roots of Phragmites in a horizontal flow reactor fed with artificial medium continuously. Axial O₂ profiles revealed that O₂ was released at a rate of 0.21 μmol O₂ cm⁻² (root surface area) h⁻¹ only in the apical region (up to ca. 40 mm from the root apex), where there was a high abundance (10⁷ to 10⁸ copies g⁻¹ biomass) of Nitrosomonas-like AOB and Nitrospira-like NOB. This abundance, however, sharply declined to the detection limit at positions more basal than 80 mm. Phylogenetic analysis based on 16S rRNA gene identified strains related to Nitrosomonas oligotropha and Nitrosomonas cryotolerans as the predominant AOB and strains related to Nitrospira marina and Nitrospira moscoviensis as the predominant NOB in the root biofilms. Based on radial O₂ microprofiles, the oxic region only extended about 0.5 mm into the surrounding sediment due to a high rate of O₂ consumption in the rhizosphere. The net NH₄⁺ and O₂ consumption rates in the apical region were higher than those determined at the oxic sediment surface in which the abundance of AOB and NOB was one order of magnitude lower than in the rhizosphere. These results clearly indicated that Phragmites root biofilms played an important role in nitrification in the waterlogged anoxic sediment.

  1. Isolation of a Seawater Tolerant Leptospira spp. from a Southern Right Whale (Eubalaena australis)

    PubMed Central

    Rago, Virginia; Uhart, Marcela

    2015-01-01

    Leptospirosis is the most widespread zoonotic disease in the world. It is caused by pathogenic spirochetes of the genus Leptospira spp. and is maintained in nature through chronic renal infection of carrier animals. Rodents and other small mammals are the main reservoirs. Information on leptospirosis in marine mammals is scarce; however, cases of leptospirosis have been documented in pinniped populations from the Pacific coast of North America from southern California to British Columbia. We report the isolation of a Leptospira spp. strain, here named Manara, from a kidney sample obtained from a Southern Right Whale (Eubalaena australis) calf, which stranded dead in Playa Manara, Península Valdés, Argentina. This strain showed motility and morphology typical of the genus Leptospira spp. under dark-field microscopy; and grew in Ellinghausen-McCullough-Johnson-Harris (EMJH) medium and Fletcher medium after 90 days of incubation at 28°C. Considering the source of this bacterium, we tested its ability to grow in Fletcher medium diluted with seawater at different percentages (1%, 3%, 5%, 7% and 10% v/v). Bacterial growth was detected 48 h after inoculation of Fletcher medium supplemented with 5% sea water, demonstrating the halophilic nature of the strain Manara. Phylogenetic analysis of 16S rRNA gene sequences placed this novel strain within the radiation of the pathogenic species of the genus Leptospira spp., with sequence similarities within the range 97–100%, and closely related to L. interrogans. Two different PCR protocols targeting genus-specific pathogenic genes (G1-G2, B64I-B64II and LigB) gave positive results, which indicates that the strain Manara is likely pathogenic. Further studies are needed to confirm this possibility as well as determine its serogroup. These results could modify our understanding of the epidemiology of this zoonosis. Until now, the resistance and ability to grow in seawater for long periods of time had been proven for the strain

  2. Isolation of a Seawater Tolerant Leptospira spp. from a Southern Right Whale (Eubalaena australis).

    PubMed

    Grune Loffler, Sylvia; Rago, Virginia; Martínez, Mara; Uhart, Marcela; Florin-Christensen, Monica; Romero, Graciela; Brihuega, Bibiana

    2015-01-01

    Leptospirosis is the most widespread zoonotic disease in the world. It is caused by pathogenic spirochetes of the genus Leptospira spp. and is maintained in nature through chronic renal infection of carrier animals. Rodents and other small mammals are the main reservoirs. Information on leptospirosis in marine mammals is scarce; however, cases of leptospirosis have been documented in pinniped populations from the Pacific coast of North America from southern California to British Columbia. We report the isolation of a Leptospira spp. strain, here named Manara, from a kidney sample obtained from a Southern Right Whale (Eubalaena australis) calf, which stranded dead in Playa Manara, Península Valdés, Argentina. This strain showed motility and morphology typical of the genus Leptospira spp. under dark-field microscopy; and grew in Ellinghausen-McCullough-Johnson-Harris (EMJH) medium and Fletcher medium after 90 days of incubation at 28°C. Considering the source of this bacterium, we tested its ability to grow in Fletcher medium diluted with seawater at different percentages (1%, 3%, 5%, 7% and 10% v/v). Bacterial growth was detected 48 h after inoculation of Fletcher medium supplemented with 5% sea water, demonstrating the halophilic nature of the strain Manara. Phylogenetic analysis of 16S rRNA gene sequences placed this novel strain within the radiation of the pathogenic species of the genus Leptospira spp., with sequence similarities within the range 97-100%, and closely related to L. interrogans. Two different PCR protocols targeting genus-specific pathogenic genes (G1-G2, B64I-B64II and LigB) gave positive results, which indicates that the strain Manara is likely pathogenic. Further studies are needed to confirm this possibility as well as determine its serogroup. These results could modify our understanding of the epidemiology of this zoonosis. Until now, the resistance and ability to grow in seawater for long periods of time had been proven for the strain

  3. Growing and Growing: Promoting Functional Thinking with Geometric Growing Patterns

    ERIC Educational Resources Information Center

    Markworth, Kimberly A.

    2010-01-01

    Design research methodology is used in this study to develop an empirically-substantiated instruction theory about students' development of functional thinking in the context of geometric growing patterns. The two research questions are: (1) How does students' functional thinking develop in the context of geometric growing patterns? (2) What are…

  4. STS-45 Earth observation of the Aurora Australis or Southern Lights

    NASA Technical Reports Server (NTRS)

    1992-01-01

    STS-45 Earth observation taken onboard Atlantis, Orbiter Vehicle (OV) 104, is of the Aurora Australis or Southern Lights. The green appearing auroral activity engulfs the thin blue line on the Earth's limb. Aurorae were observed and photographed throughout the STS-45 nine-day mission.

  5. STS-45 Earth observation of the Aurora Australis or Southern Lights

    NASA Technical Reports Server (NTRS)

    1992-01-01

    STS-45 Earth observation taken onboard Atlantis, Orbiter Vehicle (OV) 104, is of the Aurora Australis or Southern Lights. The STS-45 crewmembers note the interesting spiralling or corkscrew appearance of this particular sighting. Aurorae were observed and photographed throughout the STS-45 nine-day mission.

  6. Changes in polyphenols in "Rio Red' grapefruit leaves in response to Elsinoe australis infection

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Sweet orange scab (SOS) is a fungal disease of citrus, which is caused by Elsinoë australis. It affects the aesthetics of the fruit by forming wart-like protruded lesions on the fruit skin, and also affects the leaves, which act as source of inoculum in the orchards. SOS is widespread in the differe...

  7. Anatomy of nasal complex in the southern right whale, Eubalaena australis (Cetacea, Mysticeti)

    PubMed Central

    Buono, Mónica R; Fernández, Marta S; Fordyce, R Ewan; Reidenberg, Joy S

    2015-01-01

    The nasal region of the skull has undergone dramatic changes during the course of cetacean evolution. In particular, mysticetes (baleen whales) conserve the nasal mammalian pattern associated with the secondary function of olfaction, and lack the sound-producing specializations present in odontocetes (toothed whales, dolphins and porpoises). To improve our understanding of the morphology of the nasal region of mysticetes, we investigate the nasal anatomy, osteology and myology of the southern right whale, Eubalaena australis, and make comparisons with other mysticetes. In E. australis external deflection surfaces around the blowholes appear to divert water off the head, and differ in appearance from those observed in balaenopterids, eschrichtiids and cetotherids. In E. australis the blowholes are placed above hypertrophied nasal soft tissues formed by fat and nasal muscles, a pattern also observed in balaenopterids (rorqual mysticetes) and a cetotherid (pygmy right whale, Caperea marginata). Blowhole movements are due to the action of five nasofacial muscles: dilator naris superficialis, dilator naris profundus, depressor alae nasi, constrictor naris, and retractor alae nasi. The dilator naris profundus found in E. australis has not been previously reported in balaenopterids. The other nasofacial muscles have a similar arrangement in balaenopterids, with minor differences. A novel structure, not reported previously in any mysticete, is the presence of a vascular tissue (rete mirabile) covering the lower nasal passage. This vascular tissue could play a role in warming inspired air, or may engorge to accommodate loss of respiratory space volume due to gas compression from increased pressure during diving. PMID:25440939

  8. Biosorption and retention of orthophosphate onto Ca(OH)2-pretreated biomass of Phragmites sp.

    PubMed

    Markou, Giorgos; Mitrogiannis, Dimitris; Muylaert, Koenraad; Çelekli, Abuzer; Bozkurt, Hüseyin

    2016-07-01

    The biosorption of phosphorus in the form of orthophosphate (Po) from wastewater using biomass as the sorbent is of potential importance because the Po-loaded biomass could be applied in the agricultural sector as fertilizer and soil conditioner. However, biomass generally displays a very low affinity for Po sorption and therefore biomass surface modification is required. In the present study, the biomass (as model grinded leaves of Phragmites sp. were used) was pretreated with Ca(OH)2 to enhance Po biosorption capacity (qe). The results indicate that the alkaline pretreatment resulted in a modification of surface functional groups. It was concluded that the main sorption mechanisms were ligand exchange and electrostatic attraction. A series of experiments were conducted to investigate the performance of the pretreated biomass for Po uptake under various conditions. Isotherm and thermodynamic studies were also applied and analyzed. The biosorption process was best described by the pseudo-second order kinetic model and Langmuir isotherm, which gave a qmax of 12.27mgP/g at 25°C and pH7. The Ca(OH)2 treated Phragmites biomass applied in this study for Po recovery may present some potential advantages in terms of costs and environmental impact.

  9. Phosphorus storage and mobilization in coastal Phragmites wetlands: Influence of local-scale hydrodynamics

    NASA Astrophysics Data System (ADS)

    Karstens, Svenja; Buczko, Uwe; Glatzel, Stephan

    2016-04-01

    Coastal Phragmites wetlands are at the interface between terrestrial and aquatic ecosystems and are of paramount importance for nutrient regulation. They can act both as sinks and sources for phosphorus, depending on environmental conditions, sediment properties as well as on antecedent nutrient loading and sorption capacity of the sediments. The Darss-Zingst Bodden Chain is a shallow lagoon system at the German Baltic Sea coast with a long eutrophication history. It is lined almost at its entire length by reed wetlands. In order to elucidate under which conditions these wetlands act as sources or sinks for phosphorus, in-situ data of chemo-physical characteristics of water and sediment samples were combined with hydrodynamic measurements and laboratory experiments. Small-scale basin structures within the wetland serve as sinks for fine-grained particles rich in phosphorus, iron, manganese and organic matter. Without turbulent mixing the bottom water and the sediment surface lack replenishment of oxygen. During stagnant periods with low water level, low turbulence and thus low-oxygen conditions phosphorus from the sediments is released. But the sediments are capable of becoming sinks again once oxygen is resupplied. A thin oxic sediment surface layer rich in iron and manganese adsorbs phosphorus quickly. We demonstrate that sediments in coastal Phragmites wetlands can serve both as sources and sinks of soluble reactive phosphorus on a very short time-scale, depending on local-scale hydrodynamics and the state of the oxic-anoxic sediment interface.

  10. Phragmites sp. physiological changes in a constructed wetland treating an effluent contaminated with a diazo dye (DR81).

    PubMed

    Ferreira, Renata Alexandra; Duarte, Joana Gouveia; Vergine, Pompilio; Antunes, Carlos D; Freire, Filipe; Martins-Dias, Susete

    2014-01-01

    The role of Phragmites sp. in phytoremediation of wastewaters containing azo dyes is still, in many ways, at its initial stage of investigation. This plant response to the long-term exposure to a highly conjugated di-azo dye (Direct Red 81, DR81) was assessed using a vertical flow constructed wetland, at pilot scale. A reed bed fed with water was used as control. Changes in photosynthetic pigment content in response to the plant contact with synthetic DR81 effluent highlight Phragmites plasticity. Phragmites leaf enzymatic system responded rapidly to the stress imposed; in general, within 1 day, the up-regulation of foliar reactive oxygen species-scavenging enzymes (especially superoxide dismutase, ascorbate peroxidase (APX), glutathione peroxidase (GPX) and peroxidase) was noticed as plants entered in contact with synthetic DR81 effluent. This prompt activation decreased the endogenous levels of H₂O₂ and the malonyldialdehyde content beyond reference values. Glutathione S-transferase (GST) activity intensification was not enough to cope with stress imposed by DR81. GPX activity was pivotal for the detoxification pathways after a 24-h exposure. Carotenoid pool was depleted during this shock. After the imposed DR81 stress, plants were harvested. In the next vegetative cycle, Phragmites had already recovered from the chemical stress. Principal component analysis (PCA) highlights the role of GPX, GST, APX, and carotenoids along catalase (CAT) in the detoxification process.

  11. Applying the collective impact approach to address non-native species: A case study of the Great Lakes Phragmites Collaborative

    USGS Publications Warehouse

    Braun, H. B.; Kowalski, Kurt P.; Hollins, K.

    2016-01-01

    To address the invasion of non-native Phragmites in the Great Lakes, researchers at the U.S. Geological Survey—Great Lakes Science Center partnered with the Great Lakes Commission in 2012 to establish the Great Lakes Phragmites Collaborative (GLPC). The GLPC is a regional-scale partnership established to improve collaboration among stakeholders and increase the effectiveness of non-native Phragmites management and research. Rather than forming a traditional partnership with a narrowly defined goal, the GLPC follows the principles of collective impact to engage stakeholders, guide progress, and align resources to address this complex, regional challenge. In this paper, the concept and tenets of collective impact are described, the GLPC is offered as a model for other natural resource-focused collective impact efforts, and steps for establishing collaboratives are presented. Capitalizing on the interactive collective impact approach, the GLPC is moving toward a broadly accepted common agenda around which agencies and individuals will be able to better align their actions and generate measureable progress in the regional campaign to protect healthy, diverse ecosystems from damage caused by non-native Phragmites.

  12. Classification of retinal ganglion cells in the southern hemisphere lamprey Geotria australis (Cyclostomata).

    PubMed

    Fletcher, Lee Norman; Coimbra, João Paulo; Rodger, Jennifer; Potter, Ian C; Gill, Howard S; Dunlop, Sarah A; Collin, Shaun P

    2014-03-01

    Lampreys are one of two extant representatives of the earliest group of vertebrates, the agnathans or jawless fishes. The single species of the southern hemisphere lamprey family Geotriidae, Geotria australis, possesses the potential for pentachromatic color discrimination opposed to the mono- or dichromacy found in other lampreys. However, little is known of the retinal ganglion cell types that contribute to visual processing in G. australis. A quantitative morphological approach was used to distinguish and describe retinal ganglion cell types in G. australis. The morphology of retinal ganglion cells was revealed by retrograde biocytin labeling from the optic disc. Cells were digitally reconstructed, and somatic area and position and dendritic field size, density, tortuosity, and stratification were subjected to quantitative morphometric analyses. Cluster analysis, in conjunction with similarity profile analysis (SIMPROF), statistically identified five discrete monostratified retinal ganglion cell types, one of which may comprise two subtypes. Two bistratified types were identified separately, including a biplexiform and a bistratified subtype. The use of cluster analysis with SIMPROF provided a robust statistical technique for objectively identifying cell types whose characteristics were similar and significantly different from those of other types and thus provides an objective resolution of the problems posed by "lumpers vs. splitters" when designating cell types. The diversity of retinal ganglion cells suggests that visual information in the lamprey G. australis is processed in parallel streams, as in gnathostomes. These findings, together with the results of previous studies, indicate that the visual system of the lamprey G. australis represents the upper limit of visual complexity in extant agnathans.

  13. Wastewater treatment using integrated anaerobic baffled reactor and Bio-rack wetland planted with Phragmites sp. and Typha sp.

    PubMed

    Jamshidi, Shervin; Akbarzadeh, Abbas; Woo, Kwang-Sung; Valipour, Alireza

    2014-01-01

    The purpose of this study is to examine the potential use of anaerobic baffled reactor (ABR) followed by Bio-rack wetland planted with Phragmites sp. and Typha sp. for treating domestic wastewater generated by small communities (751 mg COD/L, 500 SCOD mg/L, 348 mg BOD5/L). Two parallel laboratory-scale models showed that the process planted with Phragmites sp. and Typha sp. are capable of removing COD by 87% & 86%, SCOD by 90% & 88%, BOD5 by 93% & 92%, TSS by 88% & 86%, TN by 79% & 77%, PO4-P by 21% & 14% at an overall HRT of 21 (843 g COD/m(3)/day & 392 g BOD5/m(3)/day) and 27 (622 g COD/m(3)/day & 302 g BOD5/m(3)/day) hours, respectively. Microbial analysis indicated a high reduction in the MPN of total coliform and TVC as high as 99% at the outlet end of the processes. The vegetated system using Phragmites sp. showed significantly greater (p <0.05) pollutant removal efficiencies due to its extensive root and mass growth rate (p <0.05) of the plant compared to Typha sp. The Phragmites sp. indicated a higher relative growth rate (3.92%) than Typha sp. (0.90%). Microorganisms immobilized on the surface of the Bio-rack media (mean TVC: 2.33 × 10(7) cfu/cm(2)) were isolated, identified and observed using scanning electron microscopy (SEM). This study illustrated that the present integrated processes could be an ideal approach for promoting a sustainable decentralization, however, Phragmites sp. would be more efficient rather than Typha sp.

  14. Dispersal of Udonella australis (Monogenea: Udonellidae) between caligid copepods Caligus rogercresseyi and Lepeophtheirus mugiloidis on Chilean rock cod.

    PubMed

    Marin, Sandra L; Carvajal, Juan; George-Nascimento, Mario

    2007-04-01

    Udonella australis is a platyhelminth that lives on the surface of the ectoparasite copepods Caligus rogercresseyi and Lepeophtheirus mugiloidis, which coexist on the Chilean rock cod Eleginops maclovinus. The absence of a planktonic oncomiracidium stage in the life cycle of udonellids may limit their dispersal ability. However, the high prevalence and intensity of U. australis on C. rogercresseyi suggest they have developed dispersal strategies to compensate for the lack of a free-living larval stage. The goals of this study were to determine the main dispersal mechanisms of U. australis in 1 copepod species and to compare the dispersal ability of U. australis between 2 different copepod species. Chilean rock cods were infected with female (without udonellids) and male (with and without udonellids) C. rogercresseyi. Other fishes were also infected with this copepod (with U. australis) and with L. mugiloidis (without U. australis). The dispersal of udonellids among copepods occurs through both intraspecific and interspecific processes. The main dispersal mechanism appears to be copepod mating; contact between same-sex individuals is less important. Intraspecific dispersal seems to be more dependent on the number of udonellids per fish than on copepod abundance, as observed for interspecific dispersal.

  15. Preparation and antibacterial activity of the oligosaccharides derived from Rhizoma Phragmites.

    PubMed

    Qian, Zhi-Gang; Jiang, Long-Fa

    2014-10-13

    In this study, we prepared Rhizoma Phragmites derived oligosaccharides (ROs) by hydrolysis with hydrogen peroxide (H2O2). The ROs yield was affected by reaction time, temperature, and H2O2 concentration. Too long reaction time and too high temperature decreased the ROs yield. Maximum ROs yield (11.26%) was obtained at reaction time 4h, temperature 75 °C, and H2O2 concentration 3.5% (v/v). The oligosaccharides sample contained 93.16% sugar, of which the average degree was approximately 11, was water-soluble, and showed white. The ROs had the highest antibacterial activity against Staphylococcus aureus, followed by Bacillus subtilis and Escherichia coli at the concentration of 100 μg/mL.

  16. Isolation and characterization of collagen from the skin of Brama australis.

    PubMed

    Sionkowska, Alina; Kozłowska, Justyna; Skorupska, Małgorzata; Michalska, Marta

    2015-09-01

    Collagen was extracted from the skin of Brama australis, the fish from warm-water sea. The yield of collagen from skin of B. australis was about 1.5% on a wet weight basis of raw material. The isolated protein was confirmed as collagen by different physico-chemical techniques such as: FTIR, SDS-PAGE, and amino acid analysis. The denaturation temperature (T(d)) of obtained collagen was found to be 24°C, what is promising as an advantage for cosmetic application. According to the electrophoretic pattern, collagen consisted of two different α-chains (α1 and α2) and was classified as type I collagen. Although T(d) of obtained collagen is higher than 20 °C it is still far from T(d) of mammalian collagen.

  17. Chonopeltis australis (Crustacea) male reproductive system morphology; sperm transfer and review of reproduction in Branchiura.

    PubMed

    Neethling, Lourelle Alicia Martins; Avenant-Oldewage, Annemariè

    2015-02-01

    The morphology of the male reproductive system as well as sperm transfer in Branchiura has been described for Dolops ranarum and Argulus japonicus. In this study, the reproductive system and accessory structures are described for male Chonopeltis australis using histology, light microscopy, and scanning electron microscopy. For the first time, we describe sperm transfer by means of a spermatophore in this genus. The internal and external morphology and mechanism of sperm transfer is compared with other Branchiura, where it has been described. The morphology of the reproductive system of C. australis is similar to that of D. ranarum while the accessory structures and the spermatophore produced are similar to that of A. japonicus. A revision of the definition of Branchiura with respect to reproduction is provided.

  18. Anatomy of nasal complex in the southern right whale, Eubalaena australis (Cetacea, Mysticeti).

    PubMed

    Buono, Mónica R; Fernández, Marta S; Fordyce, R Ewan; Reidenberg, Joy S

    2015-01-01

    The nasal region of the skull has undergone dramatic changes during the course of cetacean evolution. In particular, mysticetes (baleen whales) conserve the nasal mammalian pattern associated with the secondary function of olfaction, and lack the sound-producing specializations present in odontocetes (toothed whales, dolphins and porpoises). To improve our understanding of the morphology of the nasal region of mysticetes, we investigate the nasal anatomy, osteology and myology of the southern right whale, Eubalaena australis, and make comparisons with other mysticetes. In E. australis external deflection surfaces around the blowholes appear to divert water off the head, and differ in appearance from those observed in balaenopterids, eschrichtiids and cetotherids. In E. australis the blowholes are placed above hypertrophied nasal soft tissues formed by fat and nasal muscles, a pattern also observed in balaenopterids (rorqual mysticetes) and a cetotherid (pygmy right whale, Caperea marginata). Blowhole movements are due to the action of five nasofacial muscles: dilator naris superficialis, dilator naris profundus, depressor alae nasi, constrictor naris, and retractor alae nasi. The dilator naris profundus found in E. australis has not been previously reported in balaenopterids. The other nasofacial muscles have a similar arrangement in balaenopterids, with minor differences. A novel structure, not reported previously in any mysticete, is the presence of a vascular tissue (rete mirabile) covering the lower nasal passage. This vascular tissue could play a role in warming inspired air, or may engorge to accommodate loss of respiratory space volume due to gas compression from increased pressure during diving.

  19. Merluccius tasmanicus Matallanas & Lloris 2006 is a junior synonym of M. australis (Hutton 1872) (Gadiformes: Merluciidae) based on morphological and molecular data.

    PubMed

    Antoni, Mariana Y Deli; Delpiani, Sergio M; Stewart, Andrew L; González-Castro, Mariano; De Astarloa, Juan M Díaz

    2015-05-07

    The high intraspecific variation among and the conservative external morphology of Merluccius spp. have resulted in serious identification difficulties. Four hundred and twenty fresh and preserved specimens of Merluccius were analyzed, including the type series of Merluccius australis, M. tasmanicus and M. hubbsi; specimens of M. hubbsi from Argentina, Brazil and Uruguay, and individuals of M. australis from Argentina and New Zealand were examined. The nomenclatural status of the type specimens of M. australis is discussed and the designation of a lectotype and a paralectotype is proposed. The comparative study of morphology, meristic, traditional and landmark-based morphometry, both external and internal, and through DNA-based Barcoding molecular tools demonstrates that Merluccius tasmanicus is a junior synonym of Merluccius australis. Meristic and morphometric characters of types of M. tasmanicus completely overlap those of M. australis, whereas M. hubbsi show fewer scales along the lateral line, total vertebrae, second dorsal and anal-fin rays. A trend of a longer snout and wider head in M. australis and M. tasmanicus, and larger eyes and longer pelvic fins, in M. hubbsi was observed. While discriminant characters were found in the internal elements (hyomandibula, urohyal and sagitta otolith) between M. hubbsi and M. australis, none were observed between M. australis and those reported for M. tasmanicus. DNA barcoding analyses found no evidence of the existence of other species of Merluccius besides M. hubbsi and M. australis.

  20. Mycorrhizal compatibility and symbiotic reproduction of Gavilea australis, an endangered terrestrial orchid from south Patagonia.

    PubMed

    Fracchia, Sebastián; Aranda-Rickert, Adriana; Flachsland, Eduardo; Terada, Graciela; Sede, Silvana

    2014-11-01

    Gavilea australis is a terrestrial orchid endemic from insular south Argentina and Chile. Meeting aspects of mycorrhizal fungi identity and compatibility in this orchid species is essential for propagation and conservation purposes. These knowledge represent also a first approach to elucidate the mycorrhizal specificity of this species. In order to evaluate both the mycorrhizal compatibility and the symbiotic seed germination of G. australis, we isolated and identified its root endophytic fungal strains as well as those from two sympatric species: Gavilea lutea and Codonorchis lessonii. In addition, we tested two other strains isolated from allopatric terrestrial orchid species from central Argentina. All fungal strains formed coilings and pelotons inside protocorms and promoted, at varying degrees, seed germination, and protocorm development until seedlings had two to three leaves. These results suggest a low mycorrhizal specificity of G. australis and contribute to a better knowledge of the biology of this orchid as well as of other sympatric Patagonian orchid species, all of them currently under serious risk of extinction.

  1. A quantitative proteomic approach to highlight Phragmites sp. adaptation mechanisms to chemical stress induced by a textile dyeing pollutant.

    PubMed

    Ferreira, R A; Roma-Rodrigues, C; Davies, L C; Sá-Correia, I; Martins-Dias, S

    2016-12-15

    Phragmites sp. is present worldwide in treatment wetlands though the mechanisms involved in the phytoremediation remain unclear. In this study a quantitative proteomic approach was used to study the prompt response and adaptation of Phragmites to the textile dyeing pollutant, Acid Orange 7 (AO7). Previously, it was demonstrated that AO7 could be successfully removed from wastewater and mineralized in a constructed wetland planted with Phragmites sp. This azo dye is readily taken up by roots and transported to the plant aerial part by the xylem. Phragmites leaf samples were collected from a pilot scale vertical flow constructed wetland after 0.25, 3.25 and 24.25h exposure to AO7 (400mgL(-1)) immediately after a watering cycle used as control. Leaf soluble protein extraction yielded an average of 1560 proteins in a broad pI range (pH3-10) by two-dimensional gel electrophoresis. A time course comparative analysis of leaf proteome revealed that 40 proteins had a differential abundance compared to control (p<0.05) within a 3.25h period. After 24.25h in contact with AO7, leaf proteome was similar to control. Adaptation to AO7 involved proteins related with cellular signalling (calreticulin, Ras-related protein Rab11D and 20S proteasome), energy production and conversion (adenosine triphosphate synthase beta subunit) carbohydrate transport and metabolism (phosphoglucose isomerase, fructose-bisphosphate aldolase, monodehydroascorbate reductase, frutockinase-1 and Hypothetical protein POPTR_0003s12000g and the Uncharacterized protein LOC100272772) and photosynthesis (sedoheptulose-1,7-bisphosphatase and ferredoxin-NADP(+) reductase). Therefore, the quantitative proteomic approach used in this work indicates that mechanisms associated with stress cell signalling, energy production, carbohydrate transport and metabolism as well as proteins related with photosynthesis are key players in the initial chemical stress response in the phytoremediation process of AO7.

  2. Growing Pains (For Parents)

    MedlinePlus

    ... Lessons? Visit KidsHealth in the Classroom What Other Parents Are Reading Your Child's Development (Birth to 3 Years) Feeding Your 1- to 3-Month-Old Feeding Your 4- to 7-Month-Old Feeding Your 8- to 12-Month-Old Feeding Your 1- to 2-Year-Old Growing ... > For Parents > Growing Pains Print A A A What's in ...

  3. Differentiation of Cuscuta chinensis and Cuscuta australis by HPLC-DAD-MS analysis and HPLC-UV quantitation.

    PubMed

    He, Xianghui; Yang, Wenzhi; Ye, Min; Wang, Qing; Guo, Dean

    2011-11-01

    Cuscuta chinensis and Cuscuta australis, the two botanical sources of the Chinese herbal medicine Tu-Si-Zi, were distinguished from each other based on qualitative and quantitative chemical analysis. By HPLC‑DAD‑MS, a total of 36 compounds were characterized from these two Cuscuta species, including 14 flavonoids, 17 quinic acid derivatives, and 5 lignans. In addition, HPLC‑UV was applied to determine seven major compounds (6 flavonoids plus chlorogenic acid) in 27 batches of Tu-Si-Zi. The results revealed that the amounts of the three classes of compounds varied significantly between the species. C. australis contained more flavonoids but less quinic acid derivatives and lignans than C. chinensis. Particularly, the amounts of kaempferol and astragalin in C. australis were remarkably higher than in C. chinensis. This finding could be valuable for the quality control of Tu-Si-Zi.

  4. Phytoremediation of Water Using Phragmites karka and Veteveria nigritana in Constructed Wetland.

    PubMed

    Badejo, Adedayo A; Sridhar, Mynepalli K C; Coker, Adewale O; Ndambuki, Julius M; Kupolati, Williams K

    2015-01-01

    Constructed wetland is an innovative and emerging ecological technology for wastewater treatment. This study was conducted to investigate the effectiveness of a Vegetated Submerged Bed Constructed Wetland (VSBCW) for removal of heavy metals from industrial wastewater in a steel manufacturing company. A pilot Effluent Treatment Plant (ETP) consisting of equalization basin, two VSBCW basins and a storage tank was constructed. The VSBCW was constructed using 10-30 mm round granite for the different zones. This was overlaid by 200 mm deep granite and 150 mm washed sand with Phragmites karka, Vetiveria nigritana and Cana lilies as macrophytes. Irrigation of macrophytes using effluent from the industry was done after 3 months of planting and ETP monitored. Industrial wastewater samples were collected and analyzed for heavy metals such as zinc (Zn), lead (Pb), iron (Fe), manganese (Mn), magnesium (Mg) and chromium (Cr) to know the treatment efficiency of the ETP. Results indicated that the removal efficiencies of the VSBCW for Pb, Mg and Cr were 15.4%, 79.7% and 97.9% respectively. Fe and Mn were seen to increase by 1.8% and 33% respectively. The ETP using locally available macrophytes is effective in the phytoremediation of heavy metals, particularly Cr from the wastewater.

  5. Feasibility Study of Phragmites karka and Christella dentata Grown in West Bengal as Arsenic Accumulator.

    PubMed

    Raj, Anshita; Jamil, Sarah; Srivastava, Pankaj Kumar; Tripathi, Rudra Deo; Sharma, Yogesh Kumar; Singh, Nandita

    2015-01-01

    A survey was undertaken, in arsenic (As) contaminated area of the Nadia district, West Bengal, India, to find native As accumulator plants. As was determined both in soil and plant parts. The results showed that the mean translocation factor of Pteris vittata L, Phragmites karka (Cav.) Trin. Ex. Steud and Christella dentata Forssk were higher than 1. It thus appeared that these plants can be efficient accumulators of As. Phytoremediation ability of C. dentata and P. karka was evaluated and compared with known As-hyperaccumulators -P. vittata and Adiantum capillus veneris L. Plants were grown in the As spiked soil (25, 50, 75 and 100 mg kg(-1)). As accumulation was found to be highest in P. vittata, 117.18 mg kg(-1) in leaf at 100 mg kg(-1) As treatment, followed by A. capillus veneris, P. karka and C. dentata being 74, 83.87 and 40.36 mg kg(-1), respectively. Lipid peroxidation increased after As exposure in all plants. However, the antioxidant enzyme activity and molecules concentration also increased which helped the plants to overcome As-induced oxidative stress. The study indicates that P. karka and C. dentata could be considered as As-accumulators and find application for As-phytoextraction in field conditions.

  6. Isolation and Characterization of a Novel Antialgal Allelochemical from Phragmites communis

    PubMed Central

    Li, Feng-Min; Hu, Hong-Ying

    2005-01-01

    Antialgal allelochemicals were isolated from Phragmites communis Tris. The isolated allelopathic fraction showed strong inhibition activity on the growth of Chlorella pyrenoidosa and Microcystis aeruginosa but had no inhibition on Chlorella vulgaris. The 50% effective concentrations (EC50) of the allelopathic fractions on C. pyrenoidosa and M. aeruginosa were 0.49 and 0.79 mg/liter, respectively. The allelopathic activity of the fraction was species-specific. The isolated allelopathic fraction caused metal ion leakage from algal cells. The fraction decreased the activities of antioxidant enzymes, such as superoxide dismutase and peroxidase. The addition of the isolated fraction increased the concentration of unsaturated lipid fatty acids in cell membrane of C. pyrenoidosa and M. aeruginosa. This caused a change in plasma membrane integrity and the leakage of ions in the protoplast. The allelopathic compound was identified by nuclear magnetic resonance and gas chromatography-mass spectrometry as ethyl 2-methylacetoacetate. Synthesized ethyl 2-methylacetoacetate also showed allelopathic activity on C. pyrenoidosa and M. aeruginosa. The EC50 of synthesized ethyl 2-methylacetoacetate on C. pyrenoidosa and M. aeruginosa were 0.49 and 0.65 mg/liter, respectively. PMID:16269680

  7. Aurora Australis or Southern Lights as seen from STS-60 Shuttle Discovery

    NASA Technical Reports Server (NTRS)

    1994-01-01

    The Astronauts and Cosmonaut aboard Space Shuttle Discovery observed the display of the Aurora Australis or Southern Lights. The multi-hued shafts of light, extending upward to 200 miles above the Earth's surface, are caused by beams of energetic electrons colliding with the oxygen and nitrogen in the Earth's upper atmosphere. The strong red glow occurs at the highest altitude where the air is least dense and composed mostly of oxygen. At lower altitudes, the greater density favors the green color, also produced by atomic oxygen. Sometimes at the bottom (the lowest altitude of the aurora) a pink border is produced by nitrogen.

  8. [Identification of seeds of Cuscuta australis and C. chinensis by TLC and HPLC].

    PubMed

    Ye, M; Zhou, P; Yan, Y; Li, Y; Liu, H

    2001-02-01

    Identification of seeds of Cuscuta australis R. Br. and C. chinensis Lam. was carried out by TLC and HPLC. Polyamide membrane was used as stationary phase, MeOH-HOAc-H2O and CHCl3-MeOH-HOAc were used as mobile phase for TLC. For HPLC, Hypersil-ODS column was used; the mobile phase was MeOH-0.025 M H3PO4; the flow rate was 1.0 ml.min-1; detection wavelength was 360 nm; and column temperature was 40 degrees C. Both methods represented significant identification characteristics, and were simple, accurate and reproducible.

  9. New species causing decay on living Polylepis australis in Cordoba, central Argentina.

    PubMed

    Robledo, Gerardo; Urcelay, Carlos; Rajchenberg, Mario

    2003-01-01

    Two new species of poroid Hymenochaetaceae (Aphyllophorales, Basidiomycota) are described and illustrated. They were causing decay on living and standing dead Polylepis australis ("tabaquillo" or "queñoa") in the Córdoba Mountains in central Argentina. Inonotus serranus is characterized by a biannual basidiocarp, with a dark line separating tomentum from context; ellipsoid to ovoid, thick walled, colored spores; and the absence of setae. Phellinus uncisetus is characterized by uncinate setae with ventricose uniradicate base and well-differentiated apical portion; a basidiocarp attached by a narrow area to the substrate; ventricose, hyaline cistidioles; and by subglobose, hyaline spores, with very thick walls. The identity of Phellinus setulosus is discussed.

  10. Alpha Trianguli Australis (K2 II-III) - Hybrid or composite?

    NASA Technical Reports Server (NTRS)

    Ayres, T. R.

    1985-01-01

    The prototype hybrid-spectrum giant Alpha Trianguli Australis exhibits a far-ultraviolet continuum which is considerably bluer than would be expected of a star of its optical colors, suggesting the presence of a previously unrecognized companion. If the K-type primary is as luminous as indicated by the widths of its Ca II and H-alpha lines, the companion could be an early F-type dwarf that only recently has arrived on the main sequence. Indeed, the flux of C IV from Alpha TrA - an important measure of hybridness - would not be inconsistent with that expected from a very young chromospherically active F star.

  11. Apparatus for growing crystals

    NASA Technical Reports Server (NTRS)

    Jasinski, Thomas J. (Inventor); Witt, August F. (Inventor)

    1986-01-01

    An improved apparatus and method for growing crystals from a melt employing a heat pipe, consisting of one or more sections, each section serving to control temperature and thermal gradients in the crystal as it forms inside the pipe.

  12. How Your Baby Grows

    MedlinePlus

    ... Pregnancy > Prenatal care > Pregnancy week by week Pregnancy week by week Week by week Videos Swipe to advance Learn ... grows each week during pregnancy. Pick your week. Weeks 1-2 Conception (also called fertilization) usually happens ...

  13. The Growing Human Population.

    ERIC Educational Resources Information Center

    Keyfitz, Nathan

    1989-01-01

    Discusses the issue of human population. Illustrates the projections of the growing human population in terms of developed and less developed countries. Describes the family planning programs in several countries. Lists three references for further reading. (YP)

  14. Growing America's Energy Future

    SciTech Connect

    2016-06-01

    The emerging U.S. bioenergy industry provides a secure and growing supply of transportation fuels, biopower, and bioproducts produced from a range of abundant, renewable biomass resources. Bioenergy can help ensure a secure, sustainable, and economically sound future by reducing U.S. dependence on foreign oil, developing domestic clean energy sources, and generating domestic green jobs. Bioenergy can also help address growing concerns about climate change by reducing greenhouse gas emissions to create a healthier environment for current and future generations.

  15. The effect of sampling methods on the apparent constituents of ink from the squid Sepioteuthis australis.

    PubMed

    Madaras, F; Gerber, J P; Peddie, F; Kokkinn, M J

    2010-11-01

    Results of experiments conducted on ink recovered from the squid Sepioteuthis australis indicate that there is no epinephrine or protein naturally present in the ink as it would be ejected in vivo. Protein content was effectively zero when ink was syringed from the duct end of the ink sac of freshly killed animals. By contrast, there were proteins in samples collected from dead specimens where ink was collected by a stripping method. From these samples, a single large molecular weight protein was identified as having tyrosinase activity. Digestion of syringed ink did not yield signs of melanin-bound proteins. Analysis of supernatants after centrifugation of squid ink consistently revealed the presence of DOPA, dopamine, and taurine, whereas epinephrine and nor-epinephrine were recorded from what was believed to be contaminated ink. Histological investigations of the ink sac revealed a compartmentalised glandular structure distal to the duct end. Closer observation of the glandular tissue showed that compartments increased in size as they matured and moved further into the lumen. It was concluded that the presence of epinephrine and tyrosinase (or a related protein) in the ink of S. australis could be attributed to rupturing of basal glandular compartments or contamination from other sources during the extraction process.

  16. Burial Duration and Frequency Influences Resilience of Differing Propagule Types in a Subtidal Seagrass, Posidonia australis.

    PubMed

    Campbell, Marnie L

    2016-01-01

    Sedimentation that leads to periodic, and often prolonged, burial events is becoming more common on the world's coastlines as human populations expand and create urbanised marine environments. Different seagrass species react differently to sediment burial but many species in the southern hemisphere are yet to be examined. How seagrasses react to burial has restoration implications. There is a need to critically assess seagrass transplant propagule responses to periodic (pulse) and prolonged (press) burial events before selecting the most appropriate species, transplant propagule, and transplant site. In my study, mesocosm experiments, coupled with field measurements were used to assess how sexual (seedlings) and vegetative (sprigs) propagules of Posidonia australis responded to pulse and press burial events. Seedlings were highly susceptible to burial (both pulse and press), with no survival at the end of the experimental period. In contrast, rhizome growth in vegetative propagules was stimulated by pulse burial, although press burial events resulted in mortality. The implication for Posidonia australis restoration efforts in areas where burial is periodic, was that vegetative propagules are optimal transplant units, in comparison to seedlings. Press burial however, renders a transplant site sub-optimal for both seedling and sprig transplants.

  17. Placement of the unclassified Cyranomonas australis Lee 2002 within a novel clade of Cercozoa.

    PubMed

    Lee, Won Je; Park, Jong Soo

    2016-10-01

    Two heterotrophic flagellate strains were isolated from marine sediment samples off eastern Canada and Korea. These new isolates are indistinguishable by light microscopy from the unclassified protist Cyranomonas australis. The organisms are ovoid-shaped cells, 3.5-6μm long, laterally compressed, and somewhat flexible. They have two unequal flagella, about 1.1-2.5 times body length. Typically, the cells show a gliding motility and do not exhibit any amoeboid form or pseudopodia. 18S rDNA phylogenies clearly indicate that the isolates can be assigned to the taxon Filosa, within Cercozoa. The isolates are closest to an environmental sequence (CYSGM-16; 99% identity). Cyranomonas, CYSGM-16, and uncultured eukaryote RM1-SGM46 form a clade with strong statistical supports, here called novel clade CU (Cyranomonas plus Uncultured eukaryotes). This clade may be sister to the order Marimonadida. The novel clade CU and the Marimonadida have been detected only in marine habitats. Our findings suggest that C. australis may not belong to any previously described family within Filosa and Cercozoa.

  18. Pseudechis australis venomics: adaptation for a defense against microbial pathogens and recruitment of body transferrin.

    PubMed

    Georgieva, Dessislava; Seifert, Jana; Öhler, Michaela; von Bergen, Martin; Spencer, Patrick; Arni, Raghuvir K; Genov, Nicolay; Betzel, Christian

    2011-05-06

    The venom composition of Pseudechis australis, a widely distributed in Australia reptile, was analyzed by 2-DE and mass spectrometric analysis. In total, 102 protein spots were identified as venom toxins. The gel is dominated by horizontal trains of spots with identical or very similar molecular masses but differing in the pI values. This suggests possible post-translational modifications of toxins, changing their electrostatic charge. The results demonstrate a highly specialized biosynthesis of toxins destroying the hemostasis (P-III metalloproteases, SVMPs), antimicrobial proteins (L-amino acid oxidases, LAAOs, and transferrin-like proteins, TFLPs), and myotoxins (phospholipase A(2)s, PLA(2)s). The three transferrin isoforms of the Australian P. australis (Elapidae snake) venom are highly homologous to the body transferrin of the African Lamprophis fuliginosus (Colubridae), an indication for the recruitment of body transferrin. The venomic composition suggests an adaptation for a defense against microbial pathogens from the prey. Transferrins have not previously been reported as components of elapid or other snake venoms. Ecto-5'-nucleotidases (5'-NTDs), nerve growth factors (VNGFs), and a serine proteinase inhibitor (SPI) were also identified. The venom composition and enzymatic activities explain the clinical manifestation of the king brown snakebite. The results can be used for medical, scientific, and biotechnological purposes.

  19. Burial Duration and Frequency Influences Resilience of Differing Propagule Types in a Subtidal Seagrass, Posidonia australis

    PubMed Central

    2016-01-01

    Sedimentation that leads to periodic, and often prolonged, burial events is becoming more common on the world’s coastlines as human populations expand and create urbanised marine environments. Different seagrass species react differently to sediment burial but many species in the southern hemisphere are yet to be examined. How seagrasses react to burial has restoration implications. There is a need to critically assess seagrass transplant propagule responses to periodic (pulse) and prolonged (press) burial events before selecting the most appropriate species, transplant propagule, and transplant site. In my study, mesocosm experiments, coupled with field measurements were used to assess how sexual (seedlings) and vegetative (sprigs) propagules of Posidonia australis responded to pulse and press burial events. Seedlings were highly susceptible to burial (both pulse and press), with no survival at the end of the experimental period. In contrast, rhizome growth in vegetative propagules was stimulated by pulse burial, although press burial events resulted in mortality. The implication for Posidonia australis restoration efforts in areas where burial is periodic, was that vegetative propagules are optimal transplant units, in comparison to seedlings. Press burial however, renders a transplant site sub-optimal for both seedling and sprig transplants. PMID:27526020

  20. Influence of salinity on the life table demography of a rare Cladocera Latonopsis australis.

    PubMed

    Haridevan, G; Jyothibabu, R; Arunpandi, N; Jagadeesan, L; Biju, A

    2015-10-01

    Latonopsis australis is a rare Cladocera inhabiting the entire stretch of the Cochin backwaters, the largest monsoonal estuary along the West Coast of India, during the summer monsoon, but restricted to the upper reaches during the non-monsoon periods. Here, we present the results of an experimental study, which assessed the influence of salinity on the life table demography of the species at different salinity levels. The life table demographic parameters such as net reproduction rate, generation time, intrinsic growth rate, gross reproductive rate, and survivorship of the species were measured in different salinities ranging from freshwater to mesohaline levels (salinity 14). The study showed that higher salinity had a significant negative effect on all life table demography parameters of the species, whereas freshwater to low saline conditions (salinity up to 8) favored the survivorship, life expectancy, net production, and growth rate. It was also noticed that salinity above 8 caused a significant decrease in the survivorship, life expectancy, and reproduction rate of the species, which clearly explained the seasonal distribution pattern of the species in the Cochin backwaters. The present study suggests salinity 2 to 6 as the optimum range for the large-scale production of L. australis for purposes like live feed in aquaculture.

  1. Heavy metal content in ash of energy crops growing in sewage-contaminated natural wetlands: potential applications in agriculture and forestry?

    PubMed

    Bonanno, Giuseppe; Cirelli, Giuseppe Luigi; Toscano, Attilio; Lo Giudice, Rosa; Pavone, Pietro

    2013-05-01

    One of the greatest current challenges is to find cost-effective and eco-friendly solutions to the ever increasing needs of modern society. Some plant species are suitable for a multitude of biotechnological applications such as bioenergy production and phytoremediation. A sustainable practice is to use energy crops to clean up polluted lands or to treat wastewater in constructed wetlands without claiming further arable land for biofuel production. However, the disposal of combustion by-products may add significant costs to the whole process, especially when it deals with toxic waste. This study aimed to investigate the possibility of recycling ash from energy biomass as a fertilizer for agriculture and forestry. In particular, the concentrations of Cd, Cr, Cu, Mn, Pb and Zn were analyzed in the plant tissues and corresponding ash of the grasses Phragmites australis and Arundo donax, collected in an urban stream affected by domestic sewage. Results showed that the metal concentration in ash is 1.5-3 times as high as the values in plant tissues. However, metal enriched ash showed much lower element concentrations than the legal limits for ash reutilization in agriculture and forestry. This study found that biomass ash from constructed wetlands may be considered as a potential fertilizer rather than hazardous waste. Energy from biomass can be a really sustainable and clean option not only through the reduction of greenhouse gas emissions, but also through ash recycling for beneficial purposes, thus minimizing the negative impacts of disposal.

  2. [Effects of allelochemical isolated from Phragmites communis on algal membrane permeability].

    PubMed

    Li, Feng-Min; Hu, Hong-Ying; Chong, Yun-Xiao; Guo, Mei-Ting; Men, Yu-Jie

    2007-11-01

    Efflux of K+, Mg2+, Ca2+ ions from algal cells as signals of cell membrane permeability, inductively coupled plasma mass spectrometry (ICP-MS) as detection method of ions, the present research investigated effects of allelochemical eathyl-2-methyl acetoacetate (EMA) isolated from Phragmites communis on cell membrane permeability of Microcystis aeruginosa, Chlorella pyrenoidosa and Chlorella vulagaris. The results showed that, when the cells were boiled for 10 min and the membrane was destroyed absolutely, the K+ efflux of M. aeruginosa and C. pyrenoidosa were 1.45 and 1.59 microg x (10(9) cell) (-1), respectively. When the concentration of EMA was 2 mg x L(-1), the K+ efflux of M. aeruginosa and C. pyrenoidosa were 1.38 and 1.40 microg x (10(9) cell)(-1), respectively. The K+ efflux of M. aeruginosa and C. pyrenoidosa reached 1.44 and 1.58 microg x (10(9) cell)(-1) while the EMA was 4 mg x L(-1). When the concentrations were 2 mg x L(-1) or 4 mg x L(-1) the K+ efflux reached more than 95% of the total ion amount in M. aeruginosa and C. pyrenoidosa cells. But when EMA concentration was 4 mg x L(-1), K+ efflux of C. vulagaris was 0.64 microg x (10(9) cell)(-1), which was only 31.5% of total K+ amount in C. vulagaris. Effects EMA on efflux of Mg2+ and Ca2+ were similar to those of K+. The results indicated that EMA destroyed the cell membrane of M. aeruginosa and C. pyrenoidosa but not C. vulagaris. This is one of the mechanisms of EMA species-selective antialgal.

  3. Protosclerogibba australis gen. et sp. nov., new genus and species of sclerogibbid wasps (Hymenoptera: Sclerogibbidae) from South Africa.

    PubMed

    Olmi, Massimo; Marletta, Alessandro; Guglielmino, Adalgisa; Speranza, Stefano

    2016-03-01

    Protosclerogibba australis Olmi, Marletta, Guglielmino & Speranza, gen. et sp. nov. is described and illustrated from specimens collected in Kimberley (Northern Cape Province, South Africa). The female of the new taxon is the first micropterous sclerogibbid. Females of other extant Sclerogibbidae are always apterous, whereas fossil females can be apterous or macropterous.

  4. Precursors of Androctonus australis Scorpion Neurotoxins. Structures of Precursors, Processing Outcomes, and Expression of a Functional Recombinant Toxin II

    DTIC Science & Technology

    1989-05-24

    as well as others lethal to either insects or crustaceans (5,6). During the last 30 years, numerous works have focused on the purification and...DISCUSSION The range of Androctonus australis is North Africa. The venoms of animals collected in Chellala ( Algeria ) and Tozeur (Tunisia) have been

  5. Growing Old in Sweden.

    ERIC Educational Resources Information Center

    Berglind, Hans

    This document contains the bases of lectures delivered in Florida by a visiting Stockholm University sociology professor. The first chapter, "Growing Old in Sweden," includes information on the income, standard of living, and quality of services available to the elderly in that country. That information is presented within the changing…

  6. Growing into Leadership

    ERIC Educational Resources Information Center

    Alvy, Harvey; Robbins, Pam

    2005-01-01

    New school principals have the necessity to lead at the very time they are learning the ropes of their new jobs. Some essential themes are identified that can guide new principals into growing in their new leadership roles, which are presented and discussed.

  7. Growing through Literature.

    ERIC Educational Resources Information Center

    Thomas, Barbara J.

    "Growing through Literature" is a curriculum using Joan M. and Erik H. Erikson's theory of the Life Cycle as a structure for selecting and teaching literature to inner-city high school students at Brighton High School in Massachusetts. The program consists of four component parts: Journals, Selected Stories, Discussion, and…

  8. Growing Up with "1984."

    ERIC Educational Resources Information Center

    Franza, August

    1983-01-01

    Relates changing student reaction to George Orwell's "1984" over 20 years of teaching. Finds present high school students' acceptance of Orwell's bleak world vision both a sign of student honesty and a frightening indication of the growing reality of the book. (MM)

  9. GROWING SEEDS, TEACHER'S GUIDE.

    ERIC Educational Resources Information Center

    Elementary Science Study, Newton, MA.

    THIS TEACHER'S GUIDE IS DESIGNED FOR USE WITH AN ELEMENTARY SCIENCE STUDY UNIT, "GROWING SEEDS," IN WHICH SUCH BASIC SCIENCE SKILLS AND PROCESSES AS MEASUREMENT, OBSERVATION, AND HYPOTHESIS FORMATION ARE INTRODUCED THROUGH STUDENT ACTIVITIES INVOLVING SEEDS, GERMINATION, AND SEEDLING GROWTH. THE MATERIALS WERE DEVELOPED FOR USE IN…

  10. Families on the Grow.

    ERIC Educational Resources Information Center

    Lee, Irene K.; Phillips, Marjorie M.

    This correspondence course was designed to help parents better understand their growing children and themselves as parents. The introduction briefly sketches the importance of the family in child development. Each of the five illustrated lessons contains 7 to 12 pages on one aspect of family life. Each lesson contains a set of objectives, a…

  11. Natural humic substances effects on the life history traits of Latonopsis australis SARS (1888) (Cladocera--Crustacea).

    PubMed

    de Carvalho-Pereira, Ticiana Soares de Andrade; Santos, Thirza de Santana; Pestana, Edilene M S; Souza, Fábio Neves; Lage, Vivian Marina Gomes Barbosa; Nunesmaia, Bárbara Janaína Bezerra; Sena, Palloma Thaís Souza; Mariano-Neto, Eduardo; da Silva, Eduardo Mendes

    2015-02-01

    Cultivation medium is one of the first aspects to be considered in zooplankton laboratory cultivation. The use of artificial media does not concern to reproduce natural conditions to the cultivations, which may be achieved by using natural organic compounds like humic substances (HS). This study aimed to evaluate the effects of a concentrate of dissolved organic carbon (DOC) from the Negro River (NR(1)) and an extraction of humic acids (HA) from humus produced by Eisenia andrei on the life history traits of laboratory-based Latonopsis australis SARS (1888). A cohort life table approach was used to provide information about the effectiveness of NR and HA as supplements for the artificial cultivation of L. australis. Additionally, we seek to observe a maximization of L. australis artificial cultivation fitness by expanding the range of HS concentrations. The first experiment demonstrated that the females of L. australis reared under NR10 (mgDOCL(-1)) may have experienced an acceleration of the population life cycle, as the females have proportionally reproduced more and lived shorter than controls. By contrast, the use of the HA did not improve life history traits considered. The expansion of the concentration range (5, 10, 20 and 50 mgDOCL(-1)) corroborated the patterns observed on the first assay. Results for the fitness estimates combined with shorter lifespans than controls demonstrated trade-offs between reproductive output and female longevity reared under NR conditions, with NR20 been suggested as the best L. australis cultivation medium. This response might be associated with hormone-like effects.

  12. The effect of sodium chloride salinity on the growth, water status and ion content of Phragmites communis trin.

    PubMed

    Gorai, Mustapha; Vadel, Ahmedou M; Neffati, Mohamed; Khemira, Habib

    2007-07-01

    The present study deal with the physiological behavior of Phragmites communis under salt stress. The effects of salinity on growth, dry weight partitioning, water status and ion content were studied on seedlings of P. communis fed with nutrient solutions containing 0 to 600 mM NaCl. The plants grew best when irrigated with distilled water; biomass production and Relative Growth Rate (RGR) decreased with increasing salinity. Nevertheless, plants were able to produce and allocate dried matter to all their organs even at the highest salt level (600 mM NaCl). The leaves showed the lowest growth activity. Increasing salinity was accompanied by a decrease in seedling water content; aerial parts were more dehydrated than roots. Examination of the K+/Na+ selectivity revealed that salt tolerance of reed plants may be due to its capacity to limit Na+ transport and to enhance K+ transport into aerial parts resulting in a high K/Na ratio. Our results suggest an exclusive behavior towards Na+ as shown by the decreasing Na+ gradients from leaves to roots. It is concluded that Na+ exclusion mechanism appeared to be operative and contributes to salt tolerance of Phragmites.

  13. High-precision dating and correlation of ice, marine and terrestrial sequences spanning Heinrich Event 3: Testing mechanisms of interhemispheric change using New Zealand ancient kauri (Agathis australis)

    NASA Astrophysics Data System (ADS)

    Turney, Chris S. M.; Palmer, Jonathan; Bronk Ramsey, Christopher; Adolphi, Florian; Muscheler, Raimund; Hughen, Konrad A.; Staff, Richard A.; Jones, Richard T.; Thomas, Zoë A.; Fogwill, Christopher J.; Hogg, Alan

    2016-04-01

    Robustly testing hypotheses of geographic synchroneity of abrupt and extreme change during the late Pleistocene (60,000 to 11,650 years ago) requires a level of chronological precision often lacking in ice, marine and terrestrial sequences. Here we report a bidecadally-resolved New Zealand kauri (Agathis australis) tree-ring sequence spanning two millennia that preserves a record of atmospheric radiocarbon (14C) during ice-rafted debris event Heinrich Event 3 (HE3) in the North Atlantic and Antarctic Isotope Maximum 4 (AIM4) in the Southern Hemisphere. Using 14C in the marine Cariaco Basin and 10Be preserved in Greenland ice, the kauri 14C sequence allows us to precisely align sequences across this period. We observe no significant difference between atmospheric and marine 14C records during HE3, suggesting no stratification of surface waters and collapse in Atlantic Meridional Overturning Circulation (AMOC). Instead our results support recent evidence for a weakened AMOC across at least two millennia of the glacial period. Our work adds to a growing body of literature confirming that Heinrich events are not the cause of stadial cooling and suggests changes in the AMOC were not the primary driver of antiphase temperature trends between the hemispheres. Decadally-resolved 14C in ancient kauri offers a powerful new (and complementary) approach to polar ice core CH4 alignment for testing hypotheses of abrupt and extreme climate change.

  14. Macromolecular crystal growing system

    NASA Technical Reports Server (NTRS)

    Snyder, Robert S. (Inventor); Herren, Blair J. (Inventor); Carter, Daniel C. (Inventor); Yost, Vaughn H. (Inventor); Bugg, Charles E. (Inventor); Delucas, Lawrence J. (Inventor); Suddath, Fred L. (Inventor)

    1991-01-01

    A macromolecular crystal growing system especially designed for growing crystals in the low gravity of space as well as the gravity of earth includes at least one tray assembly, a carrier assembly which receives the tray, and a refrigeration-incubation module in which the carrier assembly is received. The tray assembly includes a plurality of sealed chambers with a plastic syringe and a plug means for the double tip of the syringe provided therein. Ganging mechanisms operate the syringes and plugs simultaneously in a precise and smooth operation. Preferably, the tray assemblies are mounted on ball bearing slides for smooth operation in inserting and removing the tray assemblies into the carrier assembly. The plugging mechanism also includes a loading control mechanism. A mechanism for leaving a syringe unplugged is also provided.

  15. Growing up with Retinoblastoma

    ERIC Educational Resources Information Center

    Maley, Tom

    2005-01-01

    An account is given of growing up as a child blinded as a result of a cancer of the eye known as retinoblastoma. The role of his mother is brought out, variously as a source of objective knowledge, of one's personal worth, and of the worth of other people in one's community. The strengths and weaknesses of his first school in his home area and…

  16. Severe soft tissue ossification in a southern right whale Eubalaena australis

    PubMed Central

    Sala, Luciano F. La; Pozzi, Luciana M.; McAloose, Denise; Kaplan, Frederick S.; Shore, Eileen M.; Kompanje, Erwin J. O.; Sidor, Inga F.; Musmeci, Luciana; Uhart, Marcela M.

    2013-01-01

    The carcass of a stranded southern right whale Eubalaena australis, discovered on the coast of Golfo Nuevo in Península Valdés, Argentina, exhibited extensive orthotopic and heterotopic ossification, osteochondroma-like lesions, and early degenerative joint disease. Extensive soft tissue ossification led to ankylosis of the axial skeleton in a pattern that, in many respects, appeared more similar to a disabling human genetic disorder, fibrodysplasia ossificans progressiva (FOP), than to more common skeletal system diseases in cetaceans and other species. This is the first reported case of a FOP-like condition in a marine mammal and raises important questions about conserved mechanisms of orthotopic and heterotopic ossification in this clade. PMID:23269389

  17. IRAS observations of young stellar objects in the Corona Australis dark cloud

    NASA Technical Reports Server (NTRS)

    Wilking, Bruce A.; Greene, Thomas P.; Lada, Charles J.; Meyer, Michael R.; Young, Erick T.

    1992-01-01

    The young stellar object (YSO) population associated with the dark cloud complex in Corona Australis is studied by synthesizing IRAS data with newly obtained near-IR and mid-IR photometry and previously published optical/IR data. Twenty-four YSOs in the Cr A complex are identified. The observed range of spectral energy distribution shapes and bolometric luminosities are consistent with those observed in other dark clouds. The duration and efficiency of star formation are found to be similar to the Rho Ophiuchi IR cluster. The low number of YSOs compared to other dark clouds is understood by a reevaluation of the molecular mass of the R Cr A cloud which shows it to be much less massive than previously assumed.

  18. A comparison of the impact of 'seagrass-friendly' boat mooring systems on Posidonia australis.

    PubMed

    Demers, Marie-Claire A; Davis, Andrew R; Knott, Nathan A

    2013-02-01

    Permanent boat moorings have contributed to the decline of seagrasses worldwide, prompting the development of 'seagrass-friendly' moorings. We contrasted seagrass cover and density (predominantly Posidonia australis) in the vicinity of three mooring types and nearby reference areas lacking moorings in Jervis Bay, Australia. We examined two types of 'seagrass-friendly' mooring and a conventional 'swing' mooring. 'Swing' moorings produced significant seagrass scour, denuding patches of ~9 m radius. Seagrass-friendly 'cyclone' moorings produced extensive denuded patches (average radius of ~18 m). Seagrass-friendly 'screw' moorings, conversely, had similar seagrass cover to nearby reference areas. Our findings reinforce previous work highlighting the negative effects of 'swing' and 'cyclone' moorings. In contrast, the previously unstudied 'screw' moorings were highly effective. We conclude that regular maintenance of moorings and the monitoring of surrounding seagrass are required to ensure that 'seagrass-friendly' moorings are operating effectively. This is important, as following damage Posidonia will take many decades to recover.

  19. Metazoan parasites of Brama australis from southern Chile: a tool for stock discrimination?

    PubMed

    Oliva, M E; Espinola, J F; Ñacari, L A

    2016-03-01

    The metazoan parasites of 403 specimens of the southern ray's bream Brama australis from three localities in southern Chile (Lebu 36° 70' S; 73° 40' W, Calbuco 41° 50' S; 73° 08' W and Punta Arenas 53° 10' S; 70° 50' W) were recorded. More than 23 400 parasite specimens belonging to 12 taxa were registered. Metazoan parasites were dominated by the copepod Hatschekia conifera, constituting 97% of the total number of parasites; the larval cestode Hepatoxylon trichiuri was the second most important parasite (2·1% of the total number of parasites). The remaining 10 species constituted <1% of the metazoan parasites. Parasitological evidence, based on univariate and multivariate analysis, does not support the existence of discrete stocks in the studied zone.

  20. Severe soft tissue ossification in a southern right whale Eubalaena australis.

    PubMed

    La Sala, Luciano F; Pozzi, Luciana M; McAloose, Denise; Kaplan, Frederick S; Shore, Eileen M; Kompanje, Erwin J O; Sidor, Inga F; Musmeci, Luciana; Uhart, Marcela M

    2012-12-27

    The carcass of a stranded southern right whale Eubalaena australis, discovered on the coast of Golfo Nuevo in Península Valdés, Argentina, exhibited extensive orthotopic and heterotopic ossification, osteochondroma-like lesions, and early degenerative joint disease. Extensive soft tissue ossification led to ankylosis of the axial skeleton in a pattern that, in many respects, appeared more similar to a disabling human genetic disorder, fibrodysplasia ossificans progressiva (FOP), than to more common skeletal system diseases in cetaceans and other species. This is the first reported case of a FOP-like condition in a marine mammal and raises important questions about conserved mechanisms of orthotopic and heterotopic ossification in this clade.

  1. New cladiellane diterpenes from the soft coral Cladiella australis of the Andaman and Nicobar Islands.

    PubMed

    Rao, C B; Rao, D S; Satyanarayana, C; Rao, D V; Kassühlke, K E; Faulkner, D J

    1994-05-01

    Five new cladiellane diterpenes, (1R*,2R*,3R*,6S*,7S*,9R*,10R*,14R*)-3- acetoxy-6-(3-methylbutanoyloxy)cladiell-11(17)-en-7-ol [2], (1R*,2R*,3R*,6S*,7S*,9R*, 10R*,14R*)-3-butanoyloxycladiell-11(17)-en-6,7-diol [3], (1R*,2R*,3R*,6S*,9R*,10R*,14R*)-3-acetoxycladiell-7(16),11(1 7)-dien-6-ol [4], 3-acetoxycladiell-11(17)-en-6-one [5], and its stereoisomer [6], have been isolated from the soft coral Cladiella australis collected on the coasts of the Andaman and Nicobar Islands of the Indian Ocean. In addition, sclerophytins C [7] and E [8], reported earlier from Sclerophytum capitalis, were also isolated. The structures of these metabolites were elucidated by interpretation of spectral data.

  2. Retinal Amino Acid Neurochemistry of the Southern Hemisphere Lamprey, Geotria australis

    PubMed Central

    Nivison-Smith, Lisa; Collin, Shaun P.; Zhu, Yuan; Ready, Sarah; Acosta, Monica L.; Hunt, David M.; Potter, Ian C.; Kalloniatis, Michael

    2013-01-01

    Lampreys are one of the two surviving groups of the agnathan (jawless) stages in vertebrate evolution and are thus ideal candidates for elucidating the evolution of visual systems. This study investigated the retinal amino acid neurochemistry of the southern hemisphere lamprey Geotria australis during the downstream migration of the young, recently-metamorphosed juveniles to the sea and during the upstream migration of the fully-grown and sexually-maturing adults to their spawning areas. Glutamate and taurine were distributed throughout the retina, whilst GABA and glycine were confined to neurons of the inner retina matching patterns seen in most other vertebrates. Glutamine and aspartate immunoreactivity was closely matched to Müller cell morphology. Between the migratory phases, few differences were observed in the distribution of major neurotransmitters i.e. glutamate, GABA and glycine, but changes in amino acids associated with retinal metabolism i.e. glutamine and aspartate, were evident. Taurine immunoreactivity was mostly conserved between migrant stages, consistent with its role in primary cell functions such as osmoregulation. Further investigation of glutamate signalling using the probe agmatine (AGB) to map cation channel permeability revealed entry of AGB into photoreceptors and horizontal cells followed by accumulation in inner retinal neurons. Similarities in AGB profiles between upstream and downstream migrant of G. australis confirmed the conservation of glutamate neurotransmission. Finally, calcium binding proteins, calbindin and calretinin were localized to the inner retina whilst recoverin was localized to photoreceptors. Overall, conservation of major amino acid neurotransmitters and calcium-associated proteins in the lamprey retina confirms these elements as essential features of the vertebrate visual system. On the other hand, metabolic elements of the retina such as neurotransmitter precursor amino acids and Müller cells are more sensitive

  3. Edge Effects along a Seagrass Margin Result in an Increased Grazing Risk on Posidonia australis Transplants

    PubMed Central

    Statton, John; Gustin-Craig, Samuel; Dixon, Kingsley W.; Kendrick, Gary A.

    2015-01-01

    A key issue in habitat restoration are the changes in ecological processes that occur when fragments of habitat are lost, resulting in the persistence of habitat-degraded margins. Margins often create or enhance opportunities for negative plant-herbivore interactions, preventing natural or assisted re-establishment of native vegetation into the degraded area. However, at some distance from the habitat margin these negative interactions may relax. Here, we posit that the intensity of species interactions in a fragmented Posidonia australis seagrass meadow may be spatially dependent on proximity to the seagrass habitat edge, whereby the risk of grazing is high and the probability of survival of seagrass transplants is low. To test this, transplants were planted 2 m within the meadow, on the meadow edge at 0m, and at 2m, 10m, 30m, 50m and 100m distance from the edge of the seagrass meadow into the unvegetated sand sheet. There was an enhanced grazing risk 0-10m from the edge, but decreased sharply with increasing distances (>30m). Yet, the risk of grazing was minimal inside the seagrass meadow, indicating that grazers may use the seagrass meadow for refuge but are not actively grazing within it. The relationship between short-term herbivory risk and long-term survival was not straightforward, suggesting that other environmental filters are also affecting survival of P. australis transplants within the study area. We found that daily probability of herbivory was predictable and operating over a small spatial scale at the edge of a large, intact seagrass meadow. These findings highlight the risk from herbivory can be high, and a potential contributing factor to seagrass establishment in restoration programs. PMID:26465926

  4. Vegetation Types Alter Soil Respiration and Its Temperature Sensitivity at the Field Scale in an Estuary Wetland

    PubMed Central

    Han, Guangxuan; Xing, Qinghui; Luo, Yiqi; Rafique, Rashad; Yu, Junbao; Mikle, Nate

    2014-01-01

    Vegetation type plays an important role in regulating the temporal and spatial variation of soil respiration. Therefore, vegetation patchiness may cause high uncertainties in the estimates of soil respiration for scaling field measurements to ecosystem level. Few studies provide insights regarding the influence of vegetation types on soil respiration and its temperature sensitivity in an estuary wetland. In order to enhance the understanding of this issue, we focused on the growing season and investigated how the soil respiration and its temperature sensitivity are affected by the different vegetation (Phragmites australis, Suaeda salsa and bare soil) in the Yellow River Estuary. During the growing season, there were significant linear relationships between soil respiration rates and shoot and root biomass, respectively. On the diurnal timescale, daytime soil respiration was more dependent on net photosynthesis. A positive correlation between soil respiration and net photosynthesis at the Phragmites australis site was found. There were exponential correlations between soil respiration and soil temperature, and the fitted Q10 values varied among different vegetation types (1.81, 2.15 and 3.43 for Phragmites australis, Suaeda salsa and bare soil sites, respectively). During the growing season, the mean soil respiration was consistently higher at the Phragmites australis site (1.11 µmol CO2 m−2 s−1), followed by the Suaeda salsa site (0.77 µmol CO2 m−2 s−1) and the bare soil site (0.41 µmol CO2 m−2 s−1). The mean monthly soil respiration was positively correlated with shoot and root biomass, total C, and total N among the three vegetation patches. Our results suggest that vegetation patchiness at a field scale might have a large impact on ecosystem-scale soil respiration. Therefore, it is necessary to consider the differences in vegetation types when using models to evaluate soil respiration in an estuary wetland. PMID:24608636

  5. Vegetation types alter soil respiration and its temperature sensitivity at the field scale in an estuary wetland.

    PubMed

    Han, Guangxuan; Xing, Qinghui; Luo, Yiqi; Rafique, Rashad; Yu, Junbao; Mikle, Nate

    2014-01-01

    Vegetation type plays an important role in regulating the temporal and spatial variation of soil respiration. Therefore, vegetation patchiness may cause high uncertainties in the estimates of soil respiration for scaling field measurements to ecosystem level. Few studies provide insights regarding the influence of vegetation types on soil respiration and its temperature sensitivity in an estuary wetland. In order to enhance the understanding of this issue, we focused on the growing season and investigated how the soil respiration and its temperature sensitivity are affected by the different vegetation (Phragmites australis, Suaeda salsa and bare soil) in the Yellow River Estuary. During the growing season, there were significant linear relationships between soil respiration rates and shoot and root biomass, respectively. On the diurnal timescale, daytime soil respiration was more dependent on net photosynthesis. A positive correlation between soil respiration and net photosynthesis at the Phragmites australis site was found. There were exponential correlations between soil respiration and soil temperature, and the fitted Q10 values varied among different vegetation types (1.81, 2.15 and 3.43 for Phragmites australis, Suaeda salsa and bare soil sites, respectively). During the growing season, the mean soil respiration was consistently higher at the Phragmites australis site (1.11 µmol CO2 m(-2) s(-1)), followed by the Suaeda salsa site (0.77 µmol CO2 m(-2) s(-1)) and the bare soil site (0.41 µmol CO2 m(-2) s(-1)). The mean monthly soil respiration was positively correlated with shoot and root biomass, total C, and total N among the three vegetation patches. Our results suggest that vegetation patchiness at a field scale might have a large impact on ecosystem-scale soil respiration. Therefore, it is necessary to consider the differences in vegetation types when using models to evaluate soil respiration in an estuary wetland.

  6. Sleep to grow smart?

    PubMed

    Volk, Carina; Huber, Reto

    2015-01-01

    Sleep is undisputable an essential part of our life, if we do not sleep enough we feel the consequences the next day. The importance of sleep for healthy brain functioning has been well studied in adults, but less is known for the role of sleep in the paediatric age. Childhood and adolescence is a critical phase for brain development. The increased need for sleep during this developmental phase fosters the growing recognition for a central role of sleep during development. In this review we summarize the findings that demonstrate a close relationship between sleep and brain maturation, discuss the consequences of insufficient sleep during childhood and adolescence and outline initial attempts that have been made in order to improve sleep in this age range.

  7. Growing a market economy

    SciTech Connect

    Basu, N.; Pryor, R.J.

    1997-09-01

    This report presents a microsimulation model of a transition economy. Transition is defined as the process of moving from a state-enterprise economy to a market economy. The emphasis is on growing a market economy starting from basic microprinciples. The model described in this report extends and modifies the capabilities of Aspen, a new agent-based model that is being developed at Sandia National Laboratories on a massively parallel Paragon computer. Aspen is significantly different from traditional models of the economy. Aspen`s emphasis on disequilibrium growth paths, its analysis based on evolution and emergent behavior rather than on a mechanistic view of society, and its use of learning algorithms to simulate the behavior of some agents rather than an assumption of perfect rationality make this model well-suited for analyzing economic variables of interest from transition economies. Preliminary results from several runs of the model are included.

  8. Voyage of discovery? A comment on Koch et al. "A voyage to Terra Australis: human-mediated dispersal of cats".

    PubMed

    Andrew, Rose L; Smith, Deane; Gorrell, Jamieson C; Janes, Jasmine K

    2016-12-07

    The origins of feral cats in Australia may be understood with the help of molecular studies, but it is important that hypotheses be tested with appropriate sampling and methodology. We point out several shortcomings in the analysis by Koch et al. (BMC Evol Biol 15:262, 2015; A voyage to Terra Australis: human-mediated dispersal of cats. Dryad Digital Repository, 2015), present a reanalysis of part of the study and discuss the challenges of elucidating the early history of feral cats.

  9. Effects of parasitism and environment on shell size of the South American intertidal mud snail Heleobia australis (Gastropoda)

    NASA Astrophysics Data System (ADS)

    Alda, Pilar; Bonel, Nicolás; Cazzaniga, Néstor J.; Martorelli, Sergio R.

    2010-04-01

    The aim of this work was to evaluate the effects of parasitism and certain environmental factors on the shell size of Heleobia australis (Hydrobiidae, Cochliopinae). We report sporocysts and metacercariae of Microphallus simillimus (Microphallidae, Trematoda) parasitizing the gonad and digestive gland of H. australis specimens from two sites of Bahía Blanca estuary, Argentina. The prevalence of infection was significantly higher (34.17% in winter and 68.14% in late spring) in snails from the outer estuary at Site 2 than in those from the inner estuary at Site 1 (5.88% and 4.71% respectively). The only known definitive host for this digenean is the white-backed stilt Himantopus melanurus (Recurvirostridae, Aves), most abundant in the estuary during winter. Parasitism by M. simillimus causes variations in the shell dimensions of H. australis, the shells of infected snails being narrower than those of uninfected snails. Snails from Site 2 were found in general to be significantly smaller than those at Site 1, possibly as a result of differences in environmental factors such as the degree of exposure to wave energy, the allocation of energy to reproduction rather than growth (induced by predation and/or parasitic castrators) and anthropogenic stressors.

  10. Triton's trident: cryptic Neogene divergences in a marine clam (Lasaea australis) correspond to Australia's three temperate biogeographic provinces.

    PubMed

    Li, Jingchun; Foighil, Diarmaid O; Park, Joong-Ki

    2013-04-01

    The southern coast of Australia is composed of three distinct biogeographic provinces distinguished primarily by intertidal community composition. Several ecological mechanisms have been proposed to explain their formation and persistence, but no consensus has been reached. The marine clam Lasaea australis is arguably the most common bivalve on southern Australian rocky shores and occurs in all three provinces. Here, we tested if this species exhibits cryptic genetic structuring corresponding to the provinces and if so, what mechanisms potentially drove its divergence. Variation in two mitochondrial genes (16S and COIII) and one nuclear gene (ITS2) was assayed to test for genetic structuring and to reconstruct the clam's phylogenetic history. Our results showed that L. australis is comprised of three cryptic mitochondrial clades, each corresponding almost perfectly to one of the three biogeographic provinces. Divergence time estimates place their cladogenesis in the Neogene. The trident-like topology and Neogene time frame of L. australis cladogenesis are incongruent with Quaternary vicariance predictions: a two-clade topology produced by Pleistocene Bass Strait land bridge formation. We hypothesize that the interaction of the Middle Miocene Climate Transition with the specific geography of the southern coastline of Australia was the primary cladogenic driver in this clam lineage. Additional in-depth studies of the endemic southern Australian marine biota across all three provinces are needed to establish the generality of this proposed older framework for regional cladogenesis.

  11. Ontogenetic shifts in brain scaling reflect behavioral changes in the life cycle of the pouched lamprey Geotria australis

    PubMed Central

    Salas, Carlos A.; Yopak, Kara E.; Warrington, Rachael E.; Hart, Nathan S.; Potter, Ian C.; Collin, Shaun P.

    2015-01-01

    Very few studies have described brain scaling in vertebrates throughout ontogeny and none in lampreys, one of the two surviving groups of the early agnathan (jawless) stage in vertebrate evolution. The life cycle of anadromous parasitic lampreys comprises two divergent trophic phases, firstly filter-feeding as larvae in freshwater and secondly parasitism as adults in the sea, with the transition marked by a radical metamorphosis. We characterized the growth of the brain during the life cycle of the pouched lamprey Geotria australis, an anadromous parasitic lamprey, focusing on the scaling between brain and body during ontogeny and testing the hypothesis that the vast transitions in behavior and environment are reflected in differences in the scaling and relative size of the major brain subdivisions throughout life. The body and brain mass and the volume of six brain structures of G. australis, representing six points of the life cycle, were recorded, ranging from the early larval stage to the final stage of spawning and death. Brain mass does not increase linearly with body mass during the ontogeny of G. australis. During metamorphosis, brain mass increases markedly, even though the body mass does not increase, reflecting an overall growth of the brain, with particularly large increases in the volume of the optic tectum and other visual areas of the brain and, to a lesser extent, the olfactory bulbs. These results are consistent with the conclusions that ammocoetes rely predominantly on non-visual and chemosensory signals, while adults rely on both visual and olfactory cues. PMID:26283894

  12. Do the changes in temperature and light affect the functional response of the benthic mud snail Heleobia australis (Mollusca: Gastropoda)?

    PubMed

    Magalhães, Thaisa R F; Neves, Raquel A F; Valentin, Jean L; Figueiredo, Gisela M

    2014-09-01

    The aim of this study was to determine the influence of temperature increase combined to conditions of light incidence on functional response of Heleobia australis. Experiments were conducted using nine to ten food concentrations for each treatment: 20°C without light; 30°C without light and, 30°C under low light intensity. For each experiment, the functional response type III (sigmoidal) was fitted and equation parameters were determined. Results suggest that, if the sediment temperature increases, H. australis will not have its ingestion rates affected negatively, whilst its feeding behavior seems to be negatively affected by light. Ingestion rates estimated for organic content in the Guanabara Bay were: 0.34 µgC ind-1h-1 at 20°C without light, 1.44 µgC ind-1h-1 at 30°C without light and 0.64 µgC ind-1h-1 at 30°C under light incidence. Higher ingestion rates were estimated at the high temperature, even under light incidence, and temperature seems to have outweighed the light effect. In contrast, if higher carbon content is considered, despite high temperature, the experiment conducted with light incidence showed lower ingestion rates than those from the experiment at 20°C without light. This study provides the first quantification of H. australis ingestion rates and the effects that changes in temperature and light have on its feeding behavior.

  13. Growing for different ends.

    PubMed

    Catts, Oron; Zurr, Ionat

    2014-11-01

    Tissue engineering and regenerative biology are usually discussed in relation to biomedical research and applications. However, hand in hand with developments of this field in the biomedical context, other approaches and uses for non-medical ends have been explored. There is a growing interest in exploring spin off tissue engineering and regenerative biology technologies in areas such as consumer products, art and design. This paper outlines developments regarding in vitro meat and leather, actuators and bio-mechanic interfaces, speculative design and contemporary artistic practices. The authors draw on their extensive experience of using tissue engineering for non-medical ends to speculate about what lead to these applications and their possible future development and uses. Avoiding utopian and dystopian postures and using the notion of the contestable, this paper also mentions some philosophical and ethical consideration stemming from the use of non-medical approaches to tissue constructs. This article is part of a directed issue entitled: Regenerative Medicine: the challenge of translation.

  14. How Do Galaxies Grow?

    NASA Astrophysics Data System (ADS)

    2008-08-01

    Astronomers have caught multiple massive galaxies in the act of merging about 4 billion years ago. This discovery, made possible by combining the power of the best ground- and space-based telescopes, uniquely supports the favoured theory of how galaxies form. ESO PR Photo 24/08 ESO PR Photo 24/08 Merging Galaxies in Groups How do galaxies form? The most widely accepted answer to this fundamental question is the model of 'hierarchical formation', a step-wise process in which small galaxies merge to build larger ones. One can think of the galaxies forming in a similar way to how streams merge to form rivers, and how these rivers, in turn, merge to form an even larger river. This theoretical model predicts that massive galaxies grow through many merging events in their lifetime. But when did their cosmological growth spurts finish? When did the most massive galaxies get most of their mass? To answer these questions, astronomers study massive galaxies in clusters, the cosmological equivalent of cities filled with galaxies. "Whether the brightest galaxies in clusters grew substantially in the last few billion years is intensely debated. Our observations show that in this time, these galaxies have increased their mass by 50%," says Kim-Vy Tran from the University of Zürich, Switzerland, who led the research. The astronomers made use of a large ensemble of telescopes and instruments, including ESO's Very Large Telescope (VLT) and the Hubble Space Telescope, to study in great detail galaxies located 4 billion light-years away. These galaxies lie in an extraordinary system made of four galaxy groups that will assemble into a cluster. In particular, the team took images with VIMOS and spectra with FORS2, both instruments on the VLT. From these and other observations, the astronomers could identify a total of 198 galaxies belonging to these four groups. The brightest galaxies in each group contain between 100 and 1000 billion of stars, a property that makes them comparable

  15. Growing Galaxies Gently

    NASA Astrophysics Data System (ADS)

    2010-10-01

    New observations from ESO's Very Large Telescope have, for the first time, provided direct evidence that young galaxies can grow by sucking in the cool gas around them and using it as fuel for the formation of many new stars. In the first few billion years after the Big Bang the mass of a typical galaxy increased dramatically and understanding why this happened is one of the hottest problems in modern astrophysics. The results appear in the 14 October issue of the journal Nature. The first galaxies formed well before the Universe was one billion years old and were much smaller than the giant systems - including the Milky Way - that we see today. So somehow the average galaxy size has increased as the Universe has evolved. Galaxies often collide and then merge to form larger systems and this process is certainly an important growth mechanism. However, an additional, gentler way has been proposed. A European team of astronomers has used ESO's Very Large Telescope to test this very different idea - that young galaxies can also grow by sucking in cool streams of the hydrogen and helium gas that filled the early Universe and forming new stars from this primitive material. Just as a commercial company can expand either by merging with other companies, or by hiring more staff, young galaxies could perhaps also grow in two different ways - by merging with other galaxies or by accreting material. The team leader, Giovanni Cresci (Osservatorio Astrofisico di Arcetri) says: "The new results from the VLT are the first direct evidence that the accretion of pristine gas really happened and was enough to fuel vigorous star formation and the growth of massive galaxies in the young Universe." The discovery will have a major impact on our understanding of the evolution of the Universe from the Big Bang to the present day. Theories of galaxy formation and evolution may have to be re-written. The group began by selecting three very distant galaxies to see if they could find evidence

  16. Reproductive behavior in the squid Sepioteuthis australis from South Australia: ethogram of reproductive body patterns.

    PubMed

    Jantzen, Troy M; Havenhand, Jon N

    2003-06-01

    Squids use a diverse range of body patterns for communication. Each pattern consists of a series of chromatic, postural, and locomotor components that are under neural control and can change within fractions of a second. Here we describe an ethogram of 48 body pattern components from in situ observations of reproductively active Sepioteuthis australis. In addition, we identify the total time and average duration that each component is shown, to a resolution of 1 s. Our results suggest that only a few components (e.g., "Golden epaulettes," "Stitchwork fins," and "Rigid arms") are temporally common, that is, shown for more than 80% of the time. In contrast to the component classification reported for other species of squid, for this species we suggest a classification system consisting of "short acute" (lasting for < 10 s); some of these same components were also classified as "medium acute" (11-60 s) or "chronic" (> 60 s). Several body patterning components were previously unreported, as were some of the combinations observed. The significance of these patterning components is discussed within the context of the associated behaviors of the squid on the spawning grounds.

  17. Androctonus australis hector venom contributes to the interaction between neuropeptides and mast cells in pulmonary hyperresponsiveness.

    PubMed

    Chaïr-Yousfi, Imène; Laraba-Djebari, Fatima; Hammoudi-Triki, Djelila

    2015-03-01

    Lung injury and respiratory distress syndrome are frequent symptoms observed in the most severe cases of scorpion envenomation. The uncontrolled transmigration of leukocyte cells into the lung interstitium and alveolar space and pulmonary edema may be the cause of death. Mast cells can release various inflammatory mediators known to be involved in the development of lung edema following scorpion venom injection. The present study was designed to determine the evidence of neurokinin 1 (NK1) receptor and the involvement of mast cell activation to induce pulmonary edema and to increase vascular permeability after Androctonus australis hector (Aah) venom administration. To this end, mast cells were depleted using compound 48/80 (C48/80). Furthermore, the involvement of tachykinin NK1 receptors expressed on mast cell membranes was elucidated by their blocking with an antagonist. On the other hand, the ability of Aah venom to increase vascular permeability and to induce edema was also assessed by measuring the amount of Evans blue dye (EBD) extravasation in bronchoalveolar lavage (BAL) fluid and in the lungs of mice. Pulmonary edema, as assessed by the levels of EBD extravasation, was completely inhibited in compound 48/80-treated animals. Depletion by stimuli non-immunological C48/80 component markedly reduced induced inflammatory response following the venom administration. The mast cells seem to play an important role in the development of lung injury and the increase of vascular permeability in mice following the subcutaneous administration of Aah scorpion venom through the NK1 receptor.

  18. Cellular and ultrastructural characterization of the grey-morph phenotype in southern right whales (Eubalaena australis)

    PubMed Central

    Eroh, Guy D.; Clayton, Fred C.; Florell, Scott R.; Cassidy, Pamela B.; Chirife, Andrea; Marón, Carina F.; Valenzuela, Luciano O.; Campbell, Michael S.; Seger, Jon; Rowntree, Victoria J.; Leachman, Sancy A.

    2017-01-01

    Southern right whales (SRWs, Eubalena australis) are polymorphic for an X-linked pigmentation pattern known as grey morphism. Most SRWs have completely black skin with white patches on their bellies and occasionally on their backs; these patches remain white as the whale ages. Grey morphs (previously referred to as partial albinos) appear mostly white at birth, with a splattering of rounded black marks; but as the whales age, the white skin gradually changes to a brownish grey color. The cellular and developmental bases of grey morphism are not understood. Here we describe cellular and ultrastructural features of grey-morph skin in relation to that of normal, wild-type skin. Melanocytes were identified histologically and counted, and melanosomes were measured using transmission electron microscopy. Grey-morph skin had fewer melanocytes when compared to wild-type skin, suggesting reduced melanocyte survival, migration, or proliferation in these whales. Grey-morph melanocytes had smaller melanosomes relative to wild-type skin, normal transport of melanosomes to surrounding keratinocytes, and normal localization of melanin granules above the keratinocyte nuclei. These findings indicate that SRW grey-morph pigmentation patterns are caused by reduced numbers of melanocytes in the skin, as well as by reduced amounts of melanin production and/or reduced sizes of mature melanosomes. Grey morphism is distinct from piebaldism and albinism found in other species, which are genetic pigmentation conditions resulting from the local absence of melanocytes, or the inability to synthesize melanin, respectively. PMID:28170433

  19. Identification and quantification of phenolics in Australian native mint (Mentha australis R. Br.).

    PubMed

    Tang, Kitty S C; Konczak, Izabela; Zhao, Jian

    2016-02-01

    Australian native mints have traditionally been used by the aboriginal people for natural remedies; however, their bioactive components have not been studied. Antioxidant capacity and composition of phenolic compounds of Mentha australis R. Br., Lamiaceae were investigated for the first time. Phenolic compounds were analyzed by HPLC photodiode array detector, liquid chromatography high resolution mass spectrometry, tandem mass spectrometry and nuclear magnetic resonance spectroscopy. Aqueous methanolic extract of the mint exhibited comparable antioxidant capacity to the common spearmint. Major compounds identified in the extract were rosmarinic acid (160.4 ± 0.85 μg mg(-1)purified extract), neoponcirin (145.0 ± 0.42 μg gallic acid equivalent(GAE) mg(-1)), narirutin (30.3 ± 0.02 μg GAE mg(-1)), chlorogenic acid (15.4 ± 0.05 μg mg(-1)) and biochanin A (9.6 ± 0.06 μg GAE mg(-1)), while minor compounds were caffeic acid, apigenin, hesperetin and naringenin. Neoponcirin and biochanin A were identified for the first time in the Mentha genus.

  20. Cellular and ultrastructural characterization of the grey-morph phenotype in southern right whales (Eubalaena australis).

    PubMed

    Eroh, Guy D; Clayton, Fred C; Florell, Scott R; Cassidy, Pamela B; Chirife, Andrea; Marón, Carina F; Valenzuela, Luciano O; Campbell, Michael S; Seger, Jon; Rowntree, Victoria J; Leachman, Sancy A

    2017-01-01

    Southern right whales (SRWs, Eubalena australis) are polymorphic for an X-linked pigmentation pattern known as grey morphism. Most SRWs have completely black skin with white patches on their bellies and occasionally on their backs; these patches remain white as the whale ages. Grey morphs (previously referred to as partial albinos) appear mostly white at birth, with a splattering of rounded black marks; but as the whales age, the white skin gradually changes to a brownish grey color. The cellular and developmental bases of grey morphism are not understood. Here we describe cellular and ultrastructural features of grey-morph skin in relation to that of normal, wild-type skin. Melanocytes were identified histologically and counted, and melanosomes were measured using transmission electron microscopy. Grey-morph skin had fewer melanocytes when compared to wild-type skin, suggesting reduced melanocyte survival, migration, or proliferation in these whales. Grey-morph melanocytes had smaller melanosomes relative to wild-type skin, normal transport of melanosomes to surrounding keratinocytes, and normal localization of melanin granules above the keratinocyte nuclei. These findings indicate that SRW grey-morph pigmentation patterns are caused by reduced numbers of melanocytes in the skin, as well as by reduced amounts of melanin production and/or reduced sizes of mature melanosomes. Grey morphism is distinct from piebaldism and albinism found in other species, which are genetic pigmentation conditions resulting from the local absence of melanocytes, or the inability to synthesize melanin, respectively.

  1. No allocation trade-offs between flowering and sproutingin the lignotuberous, Mediterranean shrub Erica australis

    NASA Astrophysics Data System (ADS)

    Cruz, Alberto; Moreno, José M.

    2001-04-01

    Trade-offs between allocation to sexual or vegetative regeneration capacity are well established as a driving force in the life history patterns of plants in fire-prone environments. However, it is not known whether such trade-offs exist in plants which after aboveground removing disturbances, such as fire, may regenerate by sexual (seeding) or asexual (sprouting) mechanisms. We evaluated whether in the fire-recruiting resprouter Erica australis, which after fire can regenerate by seedling establishment or resprouting, a larger investment in flowers and seeds prior to being disturbed by clipping its aboveground parts would decrease subsequent sprouting, that is, its vegetative regeneration capacity. We analysed the relationships between flower and seed production and the ensuing production and growth of sprouts of six plants from thirteen different sites in central-western Spain. We found no significant relationships between measures of sexual reproductive effort and resprout production and growth 6 months after clipping the aboveground parts of the plants. No evidence of trade-offs between sexual and asexual efforts was found. Furthermore, no significant relationship was found between lignotuber total non-structural carbohydrates and sexual reproductive effort. In addition, 2 years after the disturbance, resprout biomass was positively and significantly correlated with sexual reproductive effort prior to the disturbance. This indicates that growth of resprouts was higher at the sites where plants made a greater reproductive effort. The sites that were more favourable to producing flowers and seeds could also be more favourable to resprouting.

  2. Far-infrared observations of a star-forming region in the Corona Australis dark cloud

    NASA Technical Reports Server (NTRS)

    Cruz-Gonzalez, I.; Mcbreen, B.; Fazio, G. G.

    1984-01-01

    A high-resolution far-IR (40-250-micron) survey of a 0.9-sq-deg section of the core region of the Corona Australis dark cloud (containing very young stellar objects such as T Tauri stars, Herbig Ae and Be stars, Herbig-Haro objects, and compact H II regions) is presented. Two extended far-IR sources were found, one associated with the Herbig emission-line star R CrA and the other with the irregular emission-line variable star TY CrA. The two sources have substantially more far-IR radiation than could be expected from a blackbody extrapolation of their near-IR fluxes. The total luminosities of these sources are 145 and 58 solar luminosity, respectively, implying that the embedded objects are of intermediate or low mass. The infrared observations of the sources associated with R CrA and TY CrA are consistent with models of the evolution of protostellar envelopes of intermediate mass. However, the TY CrA source appears to have passed the evolutionary stage of expelling most of the hot dust near the central source, yielding an age of about 1 Myr.

  3. Comparative sensitivity of commercially available aPTT reagents to mulga snake (Pseudechis australis) venom.

    PubMed

    Lincz, Lisa F; Scorgie, Fiona E; Johnston, Christopher I; O'Leary, Margaret; Prasad, Ritam; Seldon, Michael; Favaloro, Emmanuel; Isbister, Geoffrey K

    2014-08-01

    This study aimed to determine the relative sensitivity of activated partial thromboplastin time (aPTT) reagents to the anticoagulant effects of phospholipases in mulga snake (Pseudechis australis) venom.Twenty-one haematology laboratories participating in the Royal College of Pathologists of Australasia Quality Assurance Programs were sent human plasma samples spiked with mulga venom (n=25 total results). Results for 17 patients with mulga snake envenoming were available through the Australian Snakebite Project.Only 12 of 25 venom spiked samples returned an abnormally prolonged aPTT. Tests performed with Dade Actin FS (n=7) did not identify any of the spiked samples as abnormal. Although clotting times were significantly prolonged using the lupus anticoagulant sensitive Actin FSL (n=5, p=0.043), only one was reported as abnormal. Only laboratories using TriniCLOT aPTT S (n=6), HemosIL APTT SP (n=2) and Stago PTT-A (n=1) consistently recorded the spiked sample as being above the upper normal reference interval. Abnormally prolonged aPTTs were recorded for four of eight patients whose tests were performed with Actin FSL, five of eight patients with TriniCLOT aPTT HS, and three of three patients using TriniCLOT aPTT S.We conclude that some reagents used for routine aPTT testing are relatively insensitive to the anticoagulant effects of mulga snake venom. Tests performed with these reagents should be interpreted with caution.

  4. Southern Right Whale (Eubalaena australis) Reproductive Success is Influenced by Krill (Euphausia superba) Density and Climate

    PubMed Central

    Seyboth, Elisa; Groch, Karina R.; Dalla Rosa, Luciano; Reid, Keith; Flores, Paulo A. C.; Secchi, Eduardo R.

    2016-01-01

    The reproductive success of southern right whale (Eubalaena australis) depends on body condition and, therefore, on foraging success. This, in turn, might be affected by climatically driven change in the abundance of the species main prey, krill (Euphausia superba), on the feeding grounds. Annual data on southern right whale number of calves were obtained from aerial surveys carried out between 1997 and 2013 in southern Brazil, where the species concentrate during their breeding season. The number of calves recorded each year varied from 7 to 43 ( = 21.11 ± 11.88). Using cross-correlation analysis we examined the response of the species to climate anomalies and krill densities. Significant correlations were found with krill densities (r = 0.69, p = 0.002, lag 0 years), Oceanic Niño Index (r = −0.65, p = 0.03, lag 6 years), Antarctic Oscillation (r = 0.76, p = 0.01, lag 7 years) and Antarctic sea ice area (r = −0.68, p = 0.002, lag 0 years). Our results suggest that global climate indices influence southern right whale breeding success in southern Brazil by determining variation in food (krill) availability for the species. Therefore, increased frequency of years with reduced krill abundance, due to global warming, is likely to reduce the current rate of recovery of southern right whales from historical overexploitation. PMID:27306583

  5. Crassulacean acid metabolism enhances underwater photosynthesis and diminishes photorespiration in the aquatic plant Isoetes australis.

    PubMed

    Pedersen, Ole; Rich, Sarah Meghan; Pulido, Cristina; Cawthray, Gregory Robert; Colmer, Timothy David

    2011-04-01

    • Underwater photosynthesis by aquatic plants is often limited by low availability of CO(2), and photorespiration can be high. Some aquatic plants utilize crassulacean acid metabolism (CAM) photosynthesis. The benefits of CAM for increased underwater photosynthesis and suppression of photorespiration were evaluated for Isoetes australis, a submerged plant that inhabits shallow temporary rock pools. • Leaves high or low in malate were evaluated for underwater net photosynthesis and apparent photorespiration at a range of CO(2) and O(2) concentrations. • CAM activity was indicated by 9.7-fold higher leaf malate at dawn, compared with at dusk, and also by changes in the titratable acidity (μmol H(+) equivalents) of leaves. Leaves high in malate showed not only higher underwater net photosynthesis at low external CO(2) concentrations but also lower apparent photorespiration. Suppression by CAM of apparent photorespiration was evident at a range of O(2) concentrations, including values below air equilibrium. At a high O(2) concentration of 2.2-fold the atmospheric equilibrium concentration, net photosynthesis was reduced substantially and, although it remained positive in leaves containing high malate concentrations, it became negative in those low in malate. • CAM in aquatic plants enables higher rates of underwater net photosynthesis over large O(2) and CO(2) concentration ranges in floodwaters, via increased CO(2) fixation and suppression of photorespiration.

  6. Histological patterns of the intestinal attachment of Corynosoma australe (Acanthocephala: Polymorphidae) in Arctocephalus australis (Mammalia: Pinnipedia).

    PubMed

    Silva, Renato Z; Pereira, Joaber; Cousin, João Carlos B

    2014-12-01

    The mucosal attachment pattern of Corynosoma australe in the intestines of Arctocephalus australis is described. Normal and abnormal tissue were sampled from 32 hosts to be submitted to histological routine protocol to embedding in paraffin and permanent mounting in balsam. Corynosoma australe shows three different degrees of body depth intestinal attachment (BDINA-1-3). BDINA-1: it is exclusive of the small intestine and the parasite attaches on the villi; BDINA-2: parasite affects the Lieberkühn crypts in several depth levels and, BDINA-3: the parasite reaches the submucosa. These attachment patterns alter the mucosa by degeneration and dysfunction due to necrosis of mucosal structure, great quantities of cellular debris and significant reduction of the mucosal thickness. Other aspects are crater-like concave holes (CLCHs) as sites where C. australe could be attached-detached several times according to adult migratory processes within luminal intestine space. The submucosa shows edema probably due to the local mucosal alterations resulting in homeostatic break. There is no severe inflammatory response by host but BDINA-1 to BDINA-3 and CLCH could represent foci to secondary opportunistic infections and significant areas of malabsorption in severally infected hosts contributing to increase clinical signs of preexistent pathologies.

  7. Resting metabolic rate and heat increment of feeding in juvenile South American fur seals (Arctocephalus australis).

    PubMed

    Dassis, M; Rodríguez, D H; Ieno, E N; Denuncio, P E; Loureiro, J; Davis, R W

    2014-02-01

    Bio-energetic models used to characterize an animal's energy budget require the accurate estimate of different variables such as the resting metabolic rate (RMR) and the heat increment of feeding (HIF). In this study, we estimated the in air RMR of wild juvenile South American fur seals (SAFS; Arctocephalus australis) temporarily held in captivity by measuring oxygen consumption while at rest in a postabsorptive condition. HIF, which is an increase in metabolic rate associated with digestion, assimilation and nutrient interconversion, was estimated as the difference in resting metabolic rate between the postabsorptive condition and the first 3.5h postprandial. As data were hierarchically structured, linear mixed effect models were used to compare RMR measures under both physiological conditions. Results indicated a significant increase (61%) for the postprandial RMR compared to the postabsorptive condition, estimated at 17.93±1.84 and 11.15±1.91mL O2 min(-1)kg(-1), respectively. These values constitute the first estimation of RMR and HIF in this species, and should be considered in the energy budgets for juvenile SAFS foraging at-sea.

  8. Mitochondrial DNA diversity and population structure among southern right whales (Eubalaena australis).

    PubMed

    Patenaude, Nathalie J; Portway, Vicky A; Schaeff, Cathy M; Bannister, John L; Best, Peter B; Payne, Roger S; Rowntree, Vicky J; Rivarola, Mariana; Baker, C Scott

    2007-01-01

    The population structure and mitochondrial (mt) DNA diversity of southern right whales (Eubalaena australis) are described from 146 individuals sampled on 4 winter calving grounds (Argentina, South Africa, Western Australia, and the New Zealand sub-Antarctic) and 2 summer feeding grounds (South Georgia and south of Western Australia). Based on a consensus region of 275 base pairs of the mtDNA control region, 37 variable sites defined 37 unique haplotypes, of which only one was shared between regional samples of the Indo-Pacific and South Atlantic Oceans. Phylogenetic reconstruction of the southern right whale haplotypes revealed 2 distinct clades that differed significantly in frequencies between oceans. An analysis of molecular variance confirmed significant overall differentiation among the 4 calving grounds at both the haplotype and the nucleotype levels (F(ST) = 0.159; Phi(ST) = 0.238; P < 0.001). Haplotype diversity was significantly lower in the Indo-Pacific (h = 0.701 +/- 0.037) compared with the South Atlantic (h = 0.948 +/- 0.013), despite a longer history of exploitation and larger catches in the South Atlantic. In fact, the haplotype diversity in the Indo-Pacific basin was similar to that of the North Atlantic right whale that currently numbers about 300 animals. Multidimensional scaling of genetic differentiation suggests that gene flow occurred primarily between adjacent calving grounds within an ocean basin, with mixing of lineages from different calving grounds occurring on feeding grounds.

  9. Potentially toxic Pseudo-nitzschia species in plankton and fecal samples of Eubalaena australis from Península Valdés calving ground, Argentina

    NASA Astrophysics Data System (ADS)

    D'Agostino, Valeria C.; Hoffmeyer, Mónica S.; Almandoz, Gastón O.; Sastre, Viviana; Degrati, Mariana

    2015-12-01

    Península Valdés (PV) in Argentina is an important calving ground for the southern right whale Eubalaena australis. However, a high mortality of calves has been observed in the last years, which could be associated with phycotoxin exposure. During a sampling program conducted late in the calving seasons of 2004, 2005 and 2010, potentially toxic species of the genus Pseudo-nitzschia were observed to be an important component of the phytoplankton community and they were also found in fecal samples of two live whales and three stranded whales. In line with this, in the present study Pseudo-nitzschia australis, Pseudo-nitzschia fraudulenta, Pseudo-nitzschia pungens and the complex Pseudo-nitzschia pseudodelicatissima were identified in fecal samples and phytoplankton samples by light and electron microscopy. Although no toxin analysis was carried out in the present study, our findings suggest that E. australis could be exposed to domoic acid in their calving ground.

  10. Phylogeography of Australia's king brown snake (Pseudechis australis) reveals Pliocene divergence and Pleistocene dispersal of a top predator.

    PubMed

    Kuch, Ulrich; Keogh, J Scott; Weigel, John; Smith, Laurie A; Mebs, Dietrich

    2005-03-01

    King brown snakes or mulga snakes (Pseudechis australis) are the largest and among the most dangerous and wide-ranging venomous snakes in Australia and New Guinea. They occur in diverse habitats, are important predators, and exhibit considerable morphological variation. We infer the relationships and historical biogeography of P. australis based on phylogenetic analysis of 1,249 base pairs from the mitochondrial cytochrome b, NADH dehydrogenase subunit 4 and three adjacent tRNA genes using Bayesian, maximum-likelihood, and maximum-parsimony methods. All methods reveal deep phylogenetic structure with four strongly supported clades comprising snakes from New Guinea (I), localities all over Australia (II), the Kimberleys of Western Australia (III), and north-central Australia (IV), suggesting a much more ancient radiation than previously believed. This conclusion is robust to different molecular clock estimations indicating divergence in Pliocene or Late Miocene, after landbridge dispersal to New Guinea had occurred. While members of clades I, III and IV are medium-sized, slender snakes, those of clade II attain large sizes and a robust build, rendering them top predators in their ecosystems. Genetic differentiation within clade II is low and haplotype distribution largely incongruent with geography or colour morphs, suggesting Pleistocene dispersal and recent ecomorph evolution. Significant haplotype diversity exists in clades III and IV, implying that clade IV comprises two species. Members of clade II are broadly sympatric with members of both northern Australian clades. Thus, our data support the recognition of at least five species from within P. australis (auct.) under various criteria. We discuss biogeographical, ecological and medical implications of our findings.

  11. Transcriptome/Degradome-Wide Discovery of MicroRNAs and Transcript Targets in Two Paulownia australis Genotypes

    PubMed Central

    Niu, Suyan; Fan, Guoqiang; Xu, Enkai; Deng, Minjie; Zhao, Zhenli; Dong, Yanpeng

    2014-01-01

    MicroRNAs (miRNAs) are involved in plant growth, development, and response to biotic and abiotic stresses. Most of the miRNAs that have been identified in model plants are well characterized, but till now, no reports have previously been published concerning miRNAs in Paulownia australis. In order to investigate miRNA-guided transcript target regulation in P. australis, small RNA libraries from two P. australis (diploids, PA2; and autotetraploids, PA4) genotypes were subjected to Solexa sequencing. As a result, 10,691,271 (PA2) and 10,712,733 (PA4) clean reads were obtained, and 45 conserved miRNAs belonging to 15 families, and 31 potential novel miRNAs candidates were identified. Compared with their expression levels in the PA2 plants, 26 miRNAs were up-regulated and 15 miRNAs were down-regulated in the PA4 plants. The relative expressions of 12 miRNAs were validated by quantitative real-time polymerase chain reaction. Using the degradome approach, 53 transcript targets were identified and annotated based on Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway analysis. These targets were associated with development, stimulus response, metabolism, signaling transduction and biological regulation. Among them, 11 targets, including TCP transcription factors, auxin response factors, squamosa promoter-binding-like proteins, scarecrow-like proteins, L-type lectin-domain containing receptor kinases and zinc finger CCCH domain-containing protein, cleaved by four known miRNA family and two potentially novel miRNAs were found to be involved in regulating plant development, biotic and abiotic stresses. The findings will be helpful to facilitate studies on the functions of miRNAs and their transcript targets in Paulownia. PMID:25198709

  12. Modelling temperature, photoperiod and vernalization responses of Brunonia australis (Goodeniaceae) and Calandrinia sp. (Portulacaceae) to predict flowering time

    PubMed Central

    Cave, Robyn L.; Hammer, Graeme L.; McLean, Greg; Birch, Colin J.; Erwin, John E.; Johnston, Margaret E.

    2013-01-01

    Background and Aims Crop models for herbaceous ornamental species typically include functions for temperature and photoperiod responses, but very few incorporate vernalization, which is a requirement of many traditional crops. This study investigated the development of floriculture crop models, which describe temperature responses, plus photoperiod or vernalization requirements, using Australian native ephemerals Brunonia australis and Calandrinia sp. Methods A novel approach involved the use of a field crop modelling tool, DEVEL2. This optimization program estimates the parameters of selected functions within the development rate models using an iterative process that minimizes sum of squares residual between estimated and observed days for the phenological event. Parameter profiling and jack-knifing are included in DEVEL2 to remove bias from parameter estimates and introduce rigour into the parameter selection process. Key Results Development rate of B. australis from planting to first visible floral bud (VFB) was predicted using a multiplicative approach with a curvilinear function to describe temperature responses and a broken linear function to explain photoperiod responses. A similar model was used to describe the development rate of Calandrinia sp., except the photoperiod function was replaced with an exponential vernalization function, which explained a facultative cold requirement and included a coefficient for determining the vernalization ceiling temperature. Temperature was the main environmental factor influencing development rate for VFB to anthesis of both species and was predicted using a linear model. Conclusions The phenology models for B. australis and Calandrinia sp. described development rate from planting to VFB and from VFB to anthesis in response to temperature and photoperiod or vernalization and may assist modelling efforts of other herbaceous ornamental plants. In addition to crop management, the vernalization function could be used to

  13. Stable isotopes indicate population structuring in the southwest Atlantic population of right whales (Eubalaena australis).

    PubMed

    Vighi, Morgana; Borrell, Asunción; Crespo, Enrique A; Oliveira, Larissa R; Simões-Lopes, Paulo C; Flores, Paulo A C; García, Néstor A; Aguilar, Alex; Aguilar, Alejandro

    2014-01-01

    From the early 17th century to the 1970s southern right whales, Eubalaena australis, were subject to intense exploitation along the Atlantic coast of South America. Catches along this coast recorded by whalers originally formed a continuum from Brazil to Tierra del Fuego. Nevertheless, the recovery of the population has apparently occurred fragmentarily, and with two main areas of concentration, one off southern Brazil (Santa Catarina) and another off central Argentina (Peninsula Valdés). This pattern suggests some level of heterogeneity amongst the population, which is apparently contradicted by records that traced individuals moving throughout the whole geographical extension covered by the species in the Southwest Atlantic. To test the hypothesis of the potential occurrence of discrete subpopulations exploiting specific habitats, we investigated N, C and O isotopic values in 125 bone samples obtained from whaling factories operating in the early 1970s in southern Brazil (n=72) and from contemporary and more recent strandings occurring in central Argentina (n=53). Results indicated significant differences between the two sampling areas, being δ13C and δ18O values significantly higher in samples from southern Brazil than in those from central Argentina. This variation was consistent with isotopic baselines from the two areas, indicating the occurrence of some level of structure in the Southwest Atlantic right whale population and equally that whales more likely feed in areas commonly thought to exclusively serve as nursing grounds. Results aim at reconsidering of the units currently used in the management of the southern right whale in the Southwest Atlantic Ocean. In the context of the current die-off affecting the species in Peninsula Valdés, these results also highlight the necessity to better understand movements of individuals and precisely identify their feeding areas.

  14. Comparison of Mercury Contamination in Live and Dead Dolphins from a Newly Described Species, Tursiops australis

    PubMed Central

    Monk, Alissa; Charlton-Robb, Kate; Buddhadasa, Saman; Thompson, Ross M.

    2014-01-01

    Globally it is estimated that up to 37% of all marine mammals are at a risk of extinction, due in particular to human impacts, including coastal pollution. Dolphins are known to be at risk from anthropogenic contaminants due to their longevity and high trophic position. While it is known that beach-cast animals are often high in contaminants, it has not been possible to determine whether levels may also be high in live animals from the same populations. In this paper we quantitatively assess mercury contamination in the two main populations of a newly described dolphin species from south eastern Australia, Tursiops australis. This species appear to be limited to coastal waters in close proximity to a major urban centre, and as such is likely to be vulnerable to anthropogenic pollution. For the first time, we were able to compare blubber mercury concentrations from biopsy samples of live individuals and necropsies of beach-cast animals and show that beach-cast animals were highly contaminated with mercury, at almost three times the levels found in live animals. Levels in live animals were also high, and are attributable to chronic low dose exposure to mercury from the dolphin's diet. Measurable levels of mercury were found in a number of important prey fish species. This illustrates the potential for low dose toxins in the environment to pass through marine food webs and potentially contribute to marine mammal deaths. This study demonstrates the potential use of blubber from biopsy samples to make inferences about the health of dolphins exposed to mercury. PMID:25137255

  15. Comparison of mercury contamination in live and dead dolphins from a newly described species, Tursiops australis.

    PubMed

    Monk, Alissa; Charlton-Robb, Kate; Buddhadasa, Saman; Thompson, Ross M

    2014-01-01

    Globally it is estimated that up to 37% of all marine mammals are at a risk of extinction, due in particular to human impacts, including coastal pollution. Dolphins are known to be at risk from anthropogenic contaminants due to their longevity and high trophic position. While it is known that beach-cast animals are often high in contaminants, it has not been possible to determine whether levels may also be high in live animals from the same populations. In this paper we quantitatively assess mercury contamination in the two main populations of a newly described dolphin species from south eastern Australia, Tursiops australis. This species appear to be limited to coastal waters in close proximity to a major urban centre, and as such is likely to be vulnerable to anthropogenic pollution. For the first time, we were able to compare blubber mercury concentrations from biopsy samples of live individuals and necropsies of beach-cast animals and show that beach-cast animals were highly contaminated with mercury, at almost three times the levels found in live animals. Levels in live animals were also high, and are attributable to chronic low dose exposure to mercury from the dolphin's diet. Measurable levels of mercury were found in a number of important prey fish species. This illustrates the potential for low dose toxins in the environment to pass through marine food webs and potentially contribute to marine mammal deaths. This study demonstrates the potential use of blubber from biopsy samples to make inferences about the health of dolphins exposed to mercury.

  16. Toxicokinetic and toxicodynamic analyses of Androctonus australis hector venom in rats: Optimization of antivenom therapy

    SciTech Connect

    Hammoudi-Triki, D.; Lefort, J.; Rougeot, C.; Robbe-Vincent, A.; Bon, C.; Laraba-Djebari, F.; Choumet, V. . E-mail: vchoumet@pasteur.fr

    2007-02-01

    This paper reports the simultaneous determination of toxicokinetic and toxicodynamic properties of Androctonus australis hector venom, in the absence and presence of antivenom (F(ab'){sub 2} and Fab), in envenomed rats. After subcutaneous injection of the venom, toxins showed a complete absorption phase from the site of injection associated with a distribution into a large extravascular compartment. The injection of Fab and F(ab'){sub 2} induced the neutralization of venom antigens in the blood compartment, as well as the redistribution of venom components from the extravascular compartment to the blood compartment. Interestingly, F(ab'){sub 2} and Fab showed distinct efficiencies depending on their route of injection. F(ab'){sub 2} induced a faster venom neutralization and redistribution than Fab when injected intravenously. Fab was more effective than F(ab'){sub 2} by the intramuscular route. The hemodynamic effects of Aah venom were further investigated. Changes in mean arterial pressure and heart rate were observed in parallel with an upper airway obstruction. Fab was more effective than F(ab'){sub 2} for preventing early symptoms of envenomation, whatever their route of administration. Intraperitoneal injection of F(ab'){sub 2} and Fab was similar for the prevention of the delayed symptoms, even after a late administration. Fab was more effective than F(ab'){sub 2} in the inhibition of airway resistance, independent of the route and time of administration. These results show that the treatment for scorpion stings might be improved by the intravascular injection of a mixture of Fab and F(ab'){sub 2}. If antivenom cannot be administered intravenously, Fab might be an alternative as they are more effective than F(ab'){sub 2} when injected intramuscularly.

  17. Dorsal skin color patterns among southern right whales (Eubalaena australis): genetic basis and evolutionary significance.

    PubMed

    Schaeff, C M; Best, P B; Rowntree, V J; Payne, R; Jarvis, C; Portway, V A

    1999-01-01

    Distribution and inheritance of dorsal skin color markings among two populations of southern right whales (Eubalaena australis) suggest that two genes influence dorsal skin color. The grey-morph and partial-grey-morph phenotypes (previously known as partial albino and grey-blaze, respectively) appear to be controlled by an X-linked gene, whereas the white blaze appears controlled by an autosomal gene (recessive phenotype). Calving intervals, calf size, and length of sighting history data suggest that partial-grey-morph, white-blaze, and black cows experience similar levels of reproductive success. Grey-morph cows (XgXg) are rare or absent in the two populations, but this was not unexpected given observed population frequencies of grey-morph males (XgY) and partial-grey-morph females (XGXg). The proportion of partial-grey-morph calves produced by black cows (XGXG) suggests that the reproductive success of grey-morph males was equal to that of black males, however, larger sample sizes are required to determine whether grey-morph males tend to have shorter sighting histories. The reproductive success of white-blaze males appeared similar to that of black males among whales off Argentina. There were significantly fewer white-blaze calves than expected off South Africa, which could be due to white-blaze males experiencing reduced reproductive success or to sighting blases that result in white-marked calves being misidentified as black calves. The relative frequencies of both types of dorsal color markings varied between the South African and Argentinian right whale populations, suggesting limited nuclear gene flow between these populations; analyses using other nuclear markers are under way to confirm the extent of gene flow.

  18. Reproductive Tract Histology in South American Fur Seal Pups (Arctophoca australis).

    PubMed

    Katz, Helena; Johansson, Olle

    2017-03-01

    In the present study, a detailed histological description of the female reproductive tract of South American fur seal (Arctophoca australis) pups has been conducted. The uterine tube was covered by cuboidal to columnar epithelium; nerve fibers were present in the mesosalpinx and beneath the muscular layer. The uterus was bipartitus; the endometrial surface of the horns was lined by a simple cuboidal or columnar epithelium with deep tubular glands; caudally ("the transition area"), the epithelium changed to pseudostratified columnar, few tubular glands were present and the myometrium increased in width. A bistratified epithelium internally coated the uterine body, whereas it changed to cylindrical stratified epithelium with a highly vascularized lamina propria and a strong muscular layer in the cervix; no endometrial glands were observed in this region. From the transition area of the uterus to the vagina there were several nerve fibers and ganglia belonging to the uterovaginalis plexus. In the vestibule, hymenal folds were poorly developed; adnexa structures included the major vestibular glands and a neurovascular structure similar to the vestibular bulb. Minor vestibular glands were associated with the clitoris. The skin of the perineum was lined by a keratinized stratified epithelium, pigmented, with sebaceous glands, sweat glands and hair follicles. This is the first detailed histological description of the reproductive tract of South American fur seal pups, including the glandular adnexa and nerve structures. These results contribute to the reproductive biology in Pinniped species, and give a better understanding of the utero-placental perfusion mechanism during diving. Anat Rec, 2017. © 2017 Wiley Periodicals, Inc. Anat Rec, 300:600-613, 2017. © 2016 Wiley Periodicals, Inc.

  19. Against the odds: complete outcrossing in a monoecious clonal seagrass Posidonia australis (Posidoniaceae)

    PubMed Central

    Sinclair, Elizabeth A.; Gecan, Ilena; Krauss, Siegfried L.; Kendrick, Gary A.

    2014-01-01

    Background and Aims Seagrasses are marine, flowering plants with a hydrophilous pollination strategy. In these plants, successful mating requires dispersal of filamentous pollen grains through the water column to receptive stigmas. Approximately 40 % of seagrass species are monoecious, and therefore little pollen movement is required if inbreeding is tolerated. Outcrossing in these species is further impacted by clonality, which is variable, but can be extensive in large, dense meadows. Despite this, little is known about the interaction between clonal structure, genetic diversity and mating systems in hydrophilous taxa. Methods Polymorphic microsatellite DNA markers were used to characterize genetic diversity, clonal structure, mating system and realized pollen dispersal in two meadows of the temperate, monoecious seagrass, Posidonia australis, in Cockburn Sound, Western Australia. Key Results Within the two sampled meadows, genetic diversity was moderate among the maternal shoots (R = 0·45 and 0·64) and extremely high in the embryos (R = 0·93–0·97). Both meadows exhibited a highly clumping (or phalanx) structure among clones, with spatial autocorrelation analysis showing significant genetic structure among shoots and embryos up to 10–15 m. Outcrossing rates were not significantly different from one. Pollen dispersal distances inferred from paternity assignment averaged 30·8 and 26·8 m, which was larger than the mean clone size (12·8 and 13·8 m). Conclusions These results suggest highly effective movement of pollen in the water column. Despite strong clonal structure and moderate genetic diversity within meadows, hydrophilous pollination is an effective vector for completely outcrossed offspring. The different localized water conditions at each site (highly exposed conditions vs. weak directional flow) appear to have little influence on the success and pattern of successful pollination in the two meadows. PMID:24812250

  20. Stable Isotopes Indicate Population Structuring in the Southwest Atlantic Population of Right Whales (Eubalaena australis)

    PubMed Central

    Vighi, Morgana; Borrell, Asunción; Crespo, Enrique A.; Oliveira, Larissa R.; Simões-Lopes, Paulo C.; Flores, Paulo A. C.; García, Néstor A.; Aguilar, Alejandro

    2014-01-01

    From the early 17th century to the 1970s southern right whales, Eubalaena australis, were subject to intense exploitation along the Atlantic coast of South America. Catches along this coast recorded by whalers originally formed a continuum from Brazil to Tierra del Fuego. Nevertheless, the recovery of the population has apparently occurred fragmentarily, and with two main areas of concentration, one off southern Brazil (Santa Catarina) and another off central Argentina (Peninsula Valdés). This pattern suggests some level of heterogeneity amongst the population, which is apparently contradicted by records that traced individuals moving throughout the whole geographical extension covered by the species in the Southwest Atlantic. To test the hypothesis of the potential occurrence of discrete subpopulations exploiting specific habitats, we investigated N, C and O isotopic values in 125 bone samples obtained from whaling factories operating in the early 1970s in southern Brazil (n = 72) and from contemporary and more recent strandings occurring in central Argentina (n = 53). Results indicated significant differences between the two sampling areas, being δ13C and δ18O values significantly higher in samples from southern Brazil than in those from central Argentina. This variation was consistent with isotopic baselines from the two areas, indicating the occurrence of some level of structure in the Southwest Atlantic right whale population and equally that whales more likely feed in areas commonly thought to exclusively serve as nursing grounds. Results aim at reconsidering of the units currently used in the management of the southern right whale in the Southwest Atlantic Ocean. In the context of the current die-off affecting the species in Peninsula Valdés, these results also highlight the necessity to better understand movements of individuals and precisely identify their feeding areas. PMID:24598539

  1. Clathrin in Chara australis: Molecular Analysis and Involvement in Charasome Degradation and Constitutive Endocytosis

    PubMed Central

    Hoepflinger, Marion C.; Hoeftberger, Margit; Sommer, Aniela; Hametner, Christina; Foissner, Ilse

    2017-01-01

    Charasomes are convoluted plasma membrane domains in characean green algae. They are known to form in response to light via secretion of trans-Golgi network (TGN) vesicles and local inhibition of endocytosis. Charasomes are involved in the acidification of their aqueous environment, thereby facilitating photosynthesis-dependent carbon uptake. Charasome formation is reversible to allow cells to adapt to different light conditions. Here, we show that darkness-induced degradation of charasomes involves the formation of coated pits and coated vesicles. The darkness-induced degradation of charasomes can be inhibited by 1–2 μM ikarugamycin (IKA), which is considered to be a specific inhibitor of clathrin-dependent endocytosis. At a much higher concentration (100 μM), IKA also significantly reduces the internalization of styryl dyes, indicating uptake via clathrin-coated vesicles (CV). We are the first to present evidence, based on fine structure investigation, that IKA does not interfere with the formation of clathrin coat, but inhibits the detachment and/or further processing of coated vesicles. Both charasome degradation and constitutive endocytosis are also significantly inhibited by sterol complexing agents (methyl-ß-cyclodextrin and filipin). The absence of an additive effect, when applied together with IKA, suggests that charasome degradation and constitutive endocytosis (measured via styryl dye uptake) is not inhibited due to membrane retrieval via lipid rafts, but due to clathrin coat formation requirement of a specific set of sterols. Analysis of Chara australis clathrin proteins revealed two heavy chains and several light chains with sequence peculiarities, suggesting functional and/or species specific differences. The data obtained indicate that clathrin plays a central role not only in constitutive endocytosis but also in the degradation of charasomes, thereby representing a valuable system for studying targeted exo- and endocytosis. PMID:28184226

  2. Udonella australis n. sp. (Monogenea), an epibiont on sea-lice from native fish off southern Chile.

    PubMed

    Carvajal, Juan; Sepúlveda, Fabiola

    2002-05-01

    Udonella australis n. sp., an epibiont monogenean living on caligid copepods that infest a native fish, Eleginops maclovinus (Valenciennes), off Chile, South America is described. The species can be separated from other species by its difference in size, especially body size, and the distribution of cephalic glands, vitelline follicles and genital organs. Egg-size is intermediate in comparison with that of other species. The posterior attachment mechanism consists of few muscle fibres and clumped cement-producing glands. All previous descriptions of Udonella caligorum Johnston, 1835 from off Chile correspond to this new species.

  3. Microcavia australis (Caviidae, Rodentia), a new highly competent host of Trypanosoma cruzi I in rural communities of northwestern Argentina.

    PubMed

    Cecere, M Carla; Cardinal, Marta V; Arrabal, Juan P; Moreno, Claudio; Gürtler, Ricardo E

    2015-02-01

    Rodents are well-known hosts of Trypanosoma cruzi but little is known on the role of some caviomorph rodents. We assessed the occurrence and prevalence of T. cruzi infection in Microcavia australis ("southern mountain, desert or small cavy") and its infectiousness to the vector Triatoma infestans in four rural communities of Tafí del Valle department, northwestern Argentina. Parasite detection was performed by xenodiagnosis and polymerase chain reaction amplification of the hyper-variable region of kinetoplast DNA minicircles of T. cruzi (kDNA-PCR) from blood samples. A total of 51 cavies was captured in traps set up along cavy paths in peridomestic dry-shrub fences located between 25 and 85 m from the nearest domicile. We document the first record of M. australis naturally infected by T. cruzi. Cavies presented a very high prevalence of infection (46.3%; 95% confidence interval, CI=33.0-59.6%). Only one (4%) of 23 cavies negative by xenodiagnosis was found infected by kDNA-PCR. TcI was the only discrete typing unit identified in 12 cavies with a positive xenodiagnosis. The infectiousness to T. infestans of cavies positive by xenodiagnosis or kDNA-PCR was very high (mean, 55.8%; CI=48.4-63.1%) and exceeded 80% in 44% of the hosts. Cavies are highly-competent hosts of T. cruzi in peridomestic habitats near human dwellings in rural communities of Tucumán province in northwestern Argentina.

  4. Birth of space plant growing

    NASA Technical Reports Server (NTRS)

    Mashinskiy, A.; Nechitaylo, G.

    1983-01-01

    The attempts, and successes, to grow plants in space, and get them to fully develop, bloom and produce seeds using orchids are presented. The psychological advantages of the presence of plants onboard space vehicles and space stations is indicated.

  5. Sociology: The growing climate divide

    NASA Astrophysics Data System (ADS)

    Hoffman, Andrew J.

    2011-07-01

    Climate change has reached the level of a 'scientific consensus', but is not yet a 'social consensus'. New analysis highlights that a growing divide between liberals and conservatives in the American public is a major obstacle to achieving this end.

  6. Method for growing plants aeroponically.

    PubMed

    Zobel, R W; Del Tredici, P; Torrey, J G

    1976-03-01

    A simple, inexpensive system for growing plants with their roots bathed in nutrient mist is described. The aeroponics system uses a spinner from a home humidifier to propel nutrient solution into a polyethylene-lined plywood box atop which plants are supported on plastic light-fixture "egg crating." Success in growing a number of herbaceous and woody species, including nodulated legumes and nonlegumes, is reported.

  7. Effect of ferrous chloride on biogas production and enzymatic activities during anaerobic fermentation of cow dung and Phragmites straw.

    PubMed

    Zhang, Huayong; Tian, Yonglan; Wang, Lijun; Mi, Xueyue; Chai, Yang

    2016-06-01

    The effect of ferrous (added as FeCl2) on the anaerobic co-digestion of Phragmites straw and cow dung was studied by investigating the biogas properties, pH values, organic matter degradation (COD) and enzyme activities (cellulase, protease and dehydrogenase) at different stages of mesophilic fermentation. The results showed that Fe(2+) addition increased the cumulative biogas yields by 18.1 % by extending the peak period with high daily biogas yields. Meanwhile, the methane (CH4) contents in the Fe(2+) added groups were generally higher than the control group before the 15th day. The pH values were not significantly impacted by Fe(2+) concentrations during the fermentation process. The COD concentrations, cellulase, protease and dehydrogenase activities varied with the added Fe(2+) concentrations and the stages of the fermentation process. At the beginning stage of fermentation (4th day), Fe(2+) addition increased the biogas production by improving the cellulase and dehydrogenase activities which caused a decline in COD. At the peak stage of fermentation (8th day), Fe(2+) addition enhanced the cellulase and protease activities, and resulted in lower COD contents than the control group. When the biogas yields decreased again (13th day), the COD contents varied similar with the protease and dehydrogenase activities, whilst cellulase activities were not sensitive to Fe(2+) concentrations. At the end of fermentation (26th day), Fe(2+) addition decreased the cellulase activities, led to lower COD contents and finally resulted the lower biogas yields than the control group. Taking the whole fermentation process into account, the promoting effect of Fe(2+) addition on biogas yields was mainly attributed to the extension of the gas production peak stage and the improvement of cellulase activities.

  8. IDENTIFICATION OF RESPIRATORY AND GASTROINTESTINAL PARASITES OF THREE SPECIES OF PINNIPEDS (ARCTOCEPHALUS AUSTRALIS, ARCTOCEPHALUS GAZELLA, AND OTARIA FLAVESCENS) IN SOUTHERN BRAZIL.

    PubMed

    Jacobus, Kristy; Marigo, Juliana; Gastal, Silvia Bainy; Taniwaki, Sueli Akemi; Ruoppolo, Valeria; Catão-Dias, José Luiz; Tseng, Florina

    2016-03-01

    In order to improve understanding of parasitism in South American pinnipeds, respiratory and gastrointestinal samples were collected from 12 Arctocephalus australis (South American fur seal), one Arctocephalus gazella (Antarctic fur seal), and one Otaria flavescens (South American sea lion). Ova and larvae were microscopically identified from fecal samples and respiratory secretions collected from live A. australis undergoing rehabilitation at Centro de Recuperação de Animais Marinhos (CRAM-FURG) in Rio Grande, Rio Grande do Sul, Brazil during June-July 2012. Adult parasites were collected from the lungs and gastrointestinal tracts of animals that died while undergoing treatment or were found dead along the southern Brazil coast. Parasites were identified by polymerase chain reaction and DNA sequencing, microscopic examination, comparison with keys, and histologic examination of tissues. Lung parasites of the Parafilaroides genus (Metastrongyloidea, Filaroididae) were identified at necropsy in both A. australis and A. gazella and gastrointestinal parasites were found in all three species of pinniped studied. Gastrointestinal parasites identified in A. australis included the nematodes Contracaecum sp. and Pseudoterranova cattani, the cestodes Adenocephalus pacificus (previously Diphyllobothrium pacificum), one from the Tetrabothridae family and one undetermined, and the acanthocephalans Corynosoma sp. and Bolbosoma sp.; from A. gazella the nematode Contracaecum sp. and the acanthocephalan Corynosoma sp.; and from O. flavescens the acanthocephalan Corynosoma sp. Ova from fecal samples from A. australis represent ascarid nematodes, Parafilaroides sp., Adenocephalus pacificus, acanthocephalans, and an egg determined either to be a trematode or pseuophyllidean cestode. With limited information surrounding parasitism, these findings are an important contribution to knowledge of the health of Southern Hemisphere pinnipeds.

  9. Parasites grow larger in faster growing fish hosts.

    PubMed

    Barber, Iain

    2005-02-01

    Parasites depend on host-derived energy for growth and development, and so are potentially affected by the host's ability to acquire nutrients under competitive foraging scenarios. Although parasites might be expected to grow faster in hosts that are better at acquiring nutrients from natural ecosystems, it is also possible that the most competitive hosts are better at countering infections, if they have an improved immune response or are able to limit the availability of nutrients to parasites. I first quantified the ability of uninfected three-spined sticklebacks Gasterosteus aculeatus to compete in groups for sequentially-presented food items, and then exposed either the best or worst competitors to infective stages of the cestode Schistocephalus solidus. Fish were subsequently raised in their original groups, under competitive feeding regimes, for 96 days, after which fish and parasite growth was determined. Unexpectedly, pre-exposure host competitive ability had no effect on susceptibility to infection, or on post-infection growth rate. Furthermore, despite a 120-fold variation in parasite mass at the end of the study, pre-infection competitive ability was not related to parasite growth. The closest predictor of parasite mass was body size-corrected host growth rate, indicating that the fastest growing fish developed the largest parasites. Faster growing hosts therefore apparently provide ideal environments for growing parasites. This finding has important implications for ecology and aquaculture.

  10. [Growing old as a woman].

    PubMed

    Boyer-Weinmann, Martine

    2014-01-01

    Growing old as a woman. Since Diderot, a classic writer, and his friend Sophie Volland with whom he corresponded, debated the difference between the "handsome old man" and "beautiful old age", or a hypothetical "beautiful old woman", the representations of growing old have changed, to the benefit of women. Has the considerable contribution of female writers to the debate played a role? In what ways does literature, through its figurations of the ages of life, provide a valuable perspective of the contemporary mutations of the view of old age?

  11. Discovery of Extremely Embedded X-ray Sources in the R Coronae Australis Star Forming Core

    NASA Technical Reports Server (NTRS)

    Hamaguchi, Ken-Ji; Corcoran, Michael F.; Petre, Rob; White, Nicholas E.; Stelzer, Beate; Nedachi, Ko; Kobayashi, Naoto

    2004-01-01

    We detected three extremely embedded X-ray sources in the R Corona Australis (R CrA) star forming core, IRS 7 region. Two weak X-ray sources are associated with the VLA centimeter radio sources 10E & W, whereas the third brightest source detected in the two XMM-Newton observations on March 2003 has no counterpart at any wavelengths. The large K-band upper-limit (19.4m) measured with the University of Hawaii 88-inch Telescope and strong absorption derived in X-rays (N(sub H) approx. 2.8 x 10(exp 23)/sq cm equivalent to A(sub v) approx. 180 m) indicate that the source is younger than typical Class I protostars, i.e. a Class 0 protostar or an intermittent phase between Class 0 and Class I protostars. The X-ray luminosity was less than one thirtieth (log L(sub x) less than or approx. equals 29.3 ergs/s) in the former Chandra observation in October 2000, which suggests that the X-ray activity, probably generated by magnetic activity, is triggered by an intermittent mass accretion episode such as FU Ori type outbursts. Because the source was detected at high significance in the XMM-Newton observations (approx. 2,000 cnts), X-ray properties of such young protostars can be well investigated for the first time. The light curves were constant in the 1st observation and increased linearly by a factor of two during 30 ksec in the 2nd observation. Both spectra showed iron K lines originated in hot thin-thermal plasma and fluorescence by cold gas. They can be reproduced by an absorbed thin-thermal plasma model with a Gaussian component at 6.4 keV (kT approx. 3-4 keV, L(sub x) approx. 7-20 x 10(exp 30) ergs/s). The rising timescale of the light curves in the 2nd observation was too slow for magnetically generated X-ray flares, whereas large equivalent width of the fluorescence iron K line in the 1st observation (approx. 810 eV) requires strong partial covering of the X-ray source. These results suggest that a confined hot (perhaps accretion) spot on the protostellar core was

  12. Structure-function relationships in scorpion neurotoxins. Identification of the supperreactive lysine residue in toxin I of Androctonus australis Hector.

    PubMed

    Sampieri, F; Habersetzer-Rochat, C

    1978-07-21

    In a previous article (Habersetzer-Rochat, C. and Sampieri, R. (1976) Biochemistry 15, 2254--2261) it was demonstrated that the toxin I of the North African Scorpion Androctonus australis Hector was inactivated after reaction with iodoacetate; the toxicity loss in mice was correlated with the carboxymethylation of one superreactive residue. In the present work, alkylation of toxin I was performed with iodo[14C]-acetate. Hence, it was possible, after reduction, S-methylation and chymotryptic hydrolysis of this toxin, to isolate the peptide containing the labelled lysine residue. By automatic Edman degradation, this residue was identified as being the penultimate lysine at position 56 in the primary sequence. Comparison of three primary structures of scorpion neurotoxins and comparison in different kinds of activity seem to indicate that this lysine residue is mainly important for toxicity in mice.

  13. Trace metal concentrations in southern right whale (Eubalaena australis) at Península Valdés, Argentina.

    PubMed

    Rosas, Clara L; Gil, Mónica N; Uhart, Marcela M

    2012-06-01

    The presence of essential (Fe, Mn, Zn, Cu, Ni and Al) and non-essential trace metals (Cd and Pb) was tested in liver (N=26) and kidney (N=42) from dead Southern Right Whale (SRW--Eubalaena australis) calves found beached in Península Valdés, Argentina. Essential metals were detected in all samples, particularly in hepatic tissue; though Ni and Al were accumulated mainly in the kidney. Cd and Pb were not detected in any samples. Sex and length of calves did not influence metal levels found, nor did the geographic location of carcasses. Our findings for essential metals were similar to those reported for mysticetes in other parts of the world. Except for a previous report on one SRW calf, this is the first data on trace metals for this species in Patagonia. This information is vital for SRW management considering increasing human pressures impacting their feeding and breeding grounds.

  14. Exploring Classroom Hydroponics. Growing Ideas.

    ERIC Educational Resources Information Center

    National Gardening Association, Burlington, VT.

    Growing Ideas, the National Gardening Association's series for elementary, middle, and junior high school educators, helps teachers engage students in using plants and gardens as contexts for developing a deeper, richer understanding of the world around them. This volume's focus is on hydroponics. It presents basic hydroponics information along…

  15. Growing Crystals on the Ceiling.

    ERIC Educational Resources Information Center

    Christman, Robert A.

    1980-01-01

    Described is a method of studying growing crystals in a classroom utilizing a carrousel projector standing vertically. A saturated salt solution is placed on a slide on the lens of the projector and the heat from the projector causes the water to evaporate and salt to crystalize. (Author/DS)

  16. Growing Crystals for Infrared Detectors

    NASA Technical Reports Server (NTRS)

    Lehoczky, S. L.; Szofran, F. R.

    1984-01-01

    Unidirectional solidification yields bulk crystals with compositional homogeneity. Unidirectionaly crystal-growth furnace assembly travels vertically so crystal grows upward from bottom tapered end of ampoule. Separately controlled furnaces used for hot (upper) and cold (lower) zones. New process produces ingots with radial compositional homogeneity suitable for fabricating infrared detectors.

  17. Colleges' Earmarks Grow, Amid Criticism

    ERIC Educational Resources Information Center

    Brainard, Jeffrey; Hermes, J. J.

    2008-01-01

    A record-breaking number of Congressional pork-barrel projects this year has loaded college and university plates with more earmarks than ever before, despite growing worries that the noncompetitive grants undermine the American scientific enterprise, and in spite of promises by some lawmakers to cut back. An analysis by "The Chronicle" shows that…

  18. Growing Ideas, 1990-1993.

    ERIC Educational Resources Information Center

    Pranis, Eve, Ed.

    1993-01-01

    This series of journals includes volumes 1-4 of "Growing Ideas," a journal of garden-based learning. Each issue provides instructional ideas, horticultural information and a forum for exchange among teachers using classroom gardening to stimulate learning. Ideas in each issue are separated into three sections. The "Green Tips"…

  19. How Does Your Garlic Grow?

    ERIC Educational Resources Information Center

    Shimabukuro, Mary A.; Fearing, Vickie

    1993-01-01

    Garlic is an ideal plant for the elementary classroom. It grows rapidly in water without aeration for several weeks and remains relatively free of microbial contamination. Simple experiments with garlic purchased at grocery stores can illustrate various aspects of plant growth. (PR)

  20. Organization of growing random networks

    SciTech Connect

    Krapivsky, P. L.; Redner, S.

    2001-06-01

    The organizational development of growing random networks is investigated. These growing networks are built by adding nodes successively, and linking each to an earlier node of degree k with an attachment probability A{sub k}. When A{sub k} grows more slowly than linearly with k, the number of nodes with k links, N{sub k}(t), decays faster than a power law in k, while for A{sub k} growing faster than linearly in k, a single node emerges which connects to nearly all other nodes. When A{sub k} is asymptotically linear, N{sub k}(t){similar_to}tk{sup {minus}{nu}}, with {nu} dependent on details of the attachment probability, but in the range 2{lt}{nu}{lt}{infinity}. The combined age and degree distribution of nodes shows that old nodes typically have a large degree. There is also a significant correlation in the degrees of neighboring nodes, so that nodes of similar degree are more likely to be connected. The size distributions of the in and out components of the network with respect to a given node{emdash}namely, its {open_quotes}descendants{close_quotes} and {open_quotes}ancestors{close_quotes}{emdash}are also determined. The in component exhibits a robust s{sup {minus}2} power-law tail, where s is the component size. The out component has a typical size of order lnt, and it provides basic insights into the genealogy of the network.

  1. Consequences of Growing Up Poor.

    ERIC Educational Resources Information Center

    Duncan, Greg J., Ed.; Brooks-Gunn, Jeanne, Ed.

    The consequences and correlates of growing up poor as well as the mechanisms through which poverty influences children are explored. This book is organized with a primary focus on research findings and a secondary concern with policy implications. The chapters are: (1) "Poor Families, Poor Outcomes: The Well-Being of Children and Youth" (Jeanne…

  2. Extreme Mechanics of Growing Matter

    NASA Astrophysics Data System (ADS)

    Kuhl, Ellen

    2013-03-01

    Growth is a distinguishing feature of all living things. Unlike standard materials, living matter can autonomously respond to alterations in its environment. As a result of a continuous ultrastructural turnover and renewal of cells and extracellular matrix, living matter can undergo extreme changes in composition, size, and shape within the order of months, weeks, or days. While hard matter typically adapts by increasing its density to grow strong, soft matter adapts by increasing its volume to grow large. Here we provide a state-of-the-art review of growing matter, and compare existing mathematical models for growth and remodeling of living systems. Applications are plentiful ranging from plant growth to tumor growth, from asthma in the lungs to restenosis in the vasculature, from plastic to reconstructive surgery, and from skeletal muscle adaptation to heart failure. Using these examples, we discuss current challenges and potential future directions. We hope to initiate critical discussions around the biophysical modeling of growing matter as a powerful tool to better understand biological systems in health and disease. This research has been supported by the NSF CAREER award CMMI 0952021.

  3. Growing an Emerging Research University

    ERIC Educational Resources Information Center

    Birx, Donald L.; Anderson-Fletcher, Elizabeth; Whitney, Elizabeth

    2013-01-01

    The emerging research college or university is one of the most formidable resources a region has to reinvent and grow its economy. This paper is the first of two that outlines a process of building research universities that enhance regional technology development and facilitate flexible networks of collaboration and resource sharing. Although the…

  4. Growing Patterns: Seeing beyond Counting

    ERIC Educational Resources Information Center

    Markworth, Kimberly A.

    2012-01-01

    Over the past two decades, mathematical patterns have been acknowledged as important early components of children's development of algebraic reasoning (NCTM 2000). In particular, growing patterns have attracted significant attention as a context that helps students develop an understanding of functional relationships (Lee and Freiman 2006; Moss et…

  5. Growing Up in Interracial Families.

    ERIC Educational Resources Information Center

    Spivey, Philip; And Others

    1984-01-01

    Provides excerpts from personal accounts presented at a 1984 conference on the needs of children of interracial families: "Communicating is the Key" (Philip Spivey); "Growing Up with an Asian American Heritage" (Clarence L. Chen); "An Hispanic Perspective on Biracial, Bicultural Families" (Irma Garcia Rose); and…

  6. Digestibility and Bioavailability of the Active Components of Erica australis L. Aqueous Extracts and Their Therapeutic Potential as Acetylcholinesterase Inhibitors

    PubMed Central

    Dias, Pilar; Falé, Pedro L.; Martins, Alice; Rauter, Amélia P.

    2015-01-01

    Erica australis L. (Ericaceae) is used in traditional medicine to treat many free-radical related ailments. In the present work, the stability and biological activity of the plant aqueous extracts submitted to an in vitro digestive process were investigated. Chemical stability was monitored by HPLC-DAD and LC-MS/MS, while the bioactivities were evaluated through the inhibition of acetylcholinesterase (AChE) and DPPH radical scavenging activity. Both extracts, whose main components were flavonol glycosides, inhibited AChE, showing IC50 values of 257.9 ± 6.2 µg/mL and 296.8 ± 8.8 µg/mL for the decoction and for the infusion, respectively. Significant radical scavenging activities were also revealed by both extracts, as denoted by the IC50 values for the decoction, 6.7 ± 0.1 µg/mL, and for the infusion, 10.5 ± 0.3 µg/mL. After submission to gastric and pancreatic juices, no remarkable alterations in the composition or in the bioactivities were observed, suggesting that the extracts may pass through the gastrointestinal tract, keeping their composition and therefore their biological properties. Moreover, the bioavailability of the components of both extracts, as studied in a Caco-2 cell model, showed that compounds can permeate the membrane, which is a condition to exert their biological activities. Our results add further support to the potential of E. australis for its antioxidant and neuroprotective properties. PMID:26347794

  7. A New Dolphin Species, the Burrunan Dolphin Tursiops australis sp. nov., Endemic to Southern Australian Coastal Waters

    PubMed Central

    Charlton-Robb, Kate; Gershwin, Lisa-ann; Thompson, Ross; Austin, Jeremy; Owen, Kylie; McKechnie, Stephen

    2011-01-01

    Small coastal dolphins endemic to south-eastern Australia have variously been assigned to described species Tursiops truncatus, T. aduncus or T. maugeanus; however the specific affinities of these animals is controversial and have recently been questioned. Historically ‘the southern Australian Tursiops’ was identified as unique and was formally named Tursiops maugeanus but was later synonymised with T. truncatus. Morphologically, these coastal dolphins share some characters with both aforementioned recognised Tursiops species, but they also possess unique characters not found in either. Recent mtDNA and microsatellite genetic evidence indicates deep evolutionary divergence between this dolphin and the two currently recognised Tursiops species. However, in accordance with the recommendations of the Workshop on Cetacean Systematics, and the Unified Species Concept the use of molecular evidence alone is inadequate for describing new species. Here we describe the macro-morphological, colouration and cranial characters of these animals, assess the available and new genetic data, and conclude that multiple lines of evidence clearly indicate a new species of dolphin. We demonstrate that the syntype material of T. maugeanus comprises two different species, one of which is the historical ‘southern form of Tursiops’ most similar to T. truncatus, and the other is representative of the new species and requires formal classification. These dolphins are here described as Tursiops australis sp. nov., with the common name of ‘Burrunan Dolphin’ following Australian aboriginal narrative. The recognition of T. australis sp. nov. is particularly significant given the endemism of this new species to a small geographic region of southern and south-eastern Australia, where only two small resident populations in close proximity to a major urban and agricultural centre are known, giving them a high conservation value and making them susceptible to numerous anthropogenic threats

  8. A new dolphin species, the Burrunan Dolphin Tursiops australis sp. nov., endemic to southern Australian coastal waters.

    PubMed

    Charlton-Robb, Kate; Gershwin, Lisa-ann; Thompson, Ross; Austin, Jeremy; Owen, Kylie; McKechnie, Stephen

    2011-01-01

    Small coastal dolphins endemic to south-eastern Australia have variously been assigned to described species Tursiops truncatus, T. aduncus or T. maugeanus; however the specific affinities of these animals is controversial and have recently been questioned. Historically 'the southern Australian Tursiops' was identified as unique and was formally named Tursiops maugeanus but was later synonymised with T. truncatus. Morphologically, these coastal dolphins share some characters with both aforementioned recognised Tursiops species, but they also possess unique characters not found in either. Recent mtDNA and microsatellite genetic evidence indicates deep evolutionary divergence between this dolphin and the two currently recognised Tursiops species. However, in accordance with the recommendations of the Workshop on Cetacean Systematics, and the Unified Species Concept the use of molecular evidence alone is inadequate for describing new species. Here we describe the macro-morphological, colouration and cranial characters of these animals, assess the available and new genetic data, and conclude that multiple lines of evidence clearly indicate a new species of dolphin. We demonstrate that the syntype material of T. maugeanus comprises two different species, one of which is the historical 'southern form of Tursiops' most similar to T. truncatus, and the other is representative of the new species and requires formal classification. These dolphins are here described as Tursiops australis sp. nov., with the common name of 'Burrunan Dolphin' following Australian aboriginal narrative. The recognition of T. australis sp. nov. is particularly significant given the endemism of this new species to a small geographic region of southern and south-eastern Australia, where only two small resident populations in close proximity to a major urban and agricultural centre are known, giving them a high conservation value and making them susceptible to numerous anthropogenic threats.

  9. Stream Clustering of Growing Objects

    NASA Astrophysics Data System (ADS)

    Siddiqui, Zaigham Faraz; Spiliopoulou, Myra

    We study incremental clustering of objects that grow and accumulate over time. The objects come from a multi-table stream e.g. streams of Customer and Transaction. As the Transactions stream accumulates, the Customers’ profiles grow. First, we use an incremental propositionalisation to convert the multi-table stream into a single-table stream upon which we apply clustering. For this purpose, we develop an online version of K-Means algorithm that can handle these swelling objects and any new objects that arrive. The algorithm also monitors the quality of the model and performs re-clustering when it deteriorates. We evaluate our method on the PKDD Challenge 1999 dataset.

  10. Silicone Granulomas, a Growing Problem?

    PubMed Central

    Curreri, Alexis T.; Taylor, Gina A.; Burris, Katy

    2016-01-01

    The formation of granulomas is known to be a possible adverse effect of liquid silicone administration, used for soft tissue augmentation. Its plumping effects provide enhancement of certain body parts, such as the lips, hips, and buttocks. The desire for enhancement, perhaps influenced by popular culture and an unrealistic standard of beauty, leads individuals to seek silicone injections. There is a growing population of women and men receiving injections by unlicensed, unskilled “practitioners” not related to the healthcare profession. Complications under such circumstances are not uncommon, particularly the emergence of silicone granulomas, and the authors’ medical center has seen an increase in such cases. In this case report, the authors illustrate a young patient with significant complications from her silicone injections, review current therapies for silicone granulomas, and discuss this growing medical problem. PMID:27386046

  11. Carbonaceous Matter in Growing Nanoparticles

    NASA Astrophysics Data System (ADS)

    Johnston, M. V.; Stangl, C. M.; Horan, A. J.

    2015-12-01

    Atmospheric nanoparticles constitute the greatest portion of ambient aerosol loading by number. A major source of atmospheric nanoparticles is new particle formation (NPF), a gas to particle conversion process whereby clusters nucleate from gas phase precursors to form clusters on the order of one or a few nanometers and then grow rapidly to climatically relevant sizes. A substantial fraction of cloud condensation nuclei (CCN) are thought to arise from NPF. In order to better predict the frequency, growth rates, and climatic impacts of NPF, knowledge of the chemical mechanisms by which nucleated nanoparticles grow is needed. The two main contributors to particle growth are (neutralized) sulfate and carbonaceous matter. Particle growth by sulfuric acid condensation is generally well understood, though uncertainty remains about the extent of base neutralization and the relative roles of ammonia and amines. Much less is known about carbonaceous matter, and field measurements suggest that nitrogen-containing species are important. In this presentation, recent work by our group will be described that uses a combination of ambient measurements, laboratory experiments and computational work to study carbonaceous matter in growing nanoparticles. These studies span a range of particle sizes from the initial adsorption of molecules onto a nanometer-size ammonium bisulfate seed cluster to reactions in particles that are large enough to support condensed-phase chemistry.

  12. Elevation as a barrier: genetic structure for an Atlantic rain forest tree (Bathysa australis) in the Serra do Mar mountain range, SE Brazil

    PubMed Central

    Reis, Talita Soares; Ciampi-Guillardi, Maísa; Bajay, Miklos Maximiliano; de Souza, Anete Pereira; dos Santos, Flavio Antonio Maës

    2015-01-01

    Distance and discrete geographic barriers play a role in isolating populations, as seed and pollen dispersal become limited. Nearby populations without any geographic barrier between them may also suffer from ecological isolation driven by habitat heterogeneity, which may promote divergence by local adaptation and drift. Likewise, elevation gradients may influence the genetic structure and diversity of populations, particularly those marginally distributed. Bathysa australis (Rubiaceae) is a widespread tree along the elevation gradient of the Serra do Mar, SE Brazil. This self-compatible species is pollinated by bees and wasps and has autochoric seeds, suggesting restricted gene dispersal. We investigated the distribution of genetic diversity in six B. australis populations at two extreme sites along an elevation gradient: a lowland site (80–216 m) and an upland site (1010–1100 m.a.s.l.). Nine microsatellite loci were used to test for genetic structure and to verify differences in genetic diversity between sites. We found a marked genetic structure on a scale as small as 6 km (FST = 0.21), and two distinct clusters were identified, each corresponding to a site. Although B. australis is continuously distributed along the elevation gradient, we have not observed a gene flow between the extreme populations. This might be related to B. australis biological features and creates a potential scenario for adaptation to the different conditions imposed by the elevation gradient. We failed to find an isolation-by-distance pattern; although on the fine scale, all populations showed spatial autocorrelation until ∼10-20 m. Elevation difference was a relevant factor though, but we need further sampling effort to check its correlation with genetic distance. The lowland populations had a higher allelic richness and showed higher rare allele counts than the upland ones. The upland site may be more selective, eliminating rare alleles, as we did not find any evidence

  13. Effects of Organic and Inorganic Nitrogen on the Growth and Production of Domoic Acid by Pseudo-nitzschia multiseries and P. australis (Bacillariophyceae) in Culture

    PubMed Central

    Martin-Jézéquel, Véronique; Calu, Guillaume; Candela, Leo; Amzil, Zouher; Jauffrais, Thierry; Séchet, Véronique; Weigel, Pierre

    2015-01-01

    Over the last century, human activities have altered the global nitrogen cycle, and anthropogenic inputs of both inorganic and organic nitrogen species have increased around the world, causing significant changes to the functioning of aquatic ecosystems. The increasing frequency of Pseudo-nitzschia spp. in estuarine and coastal waters reinforces the need to understand better the environmental control of its growth and domoic acid (DA) production. Here, we document Pseudo-nitzschia spp. growth and toxicity on a large set of inorganic and organic nitrogen (nitrate, ammonium, urea, glutamate, glutamine, arginine and taurine). Our study focused on two species isolated from European coastal waters: P. multiseries CCL70 and P. australis PNC1. The nitrogen sources induced broad differences between the two species with respect to growth rate, biomass and cellular DA, but no specific variation could be attributed to any of the inorganic or organic nitrogen substrates. Enrichment with ammonium resulted in an enhanced growth rate and cell yield, whereas glutamate did not support the growth of P. multiseries. Arginine, glutamine and taurine enabled good growth of P. australis, but without toxin production. The highest DA content was produced when P. multiseries grew with urea and P. australis grew with glutamate. For both species, growth rate was not correlated with DA content but more toxin was produced when the nitrogen source could not sustain a high biomass. A significant negative correlation was found between cell biomass and DA content in P. australis. This study shows that Pseudo-nitzschia can readily utilize organic nitrogen in the form of amino acids, and confirms that both inorganic and organic nitrogen affect growth and DA production. Our results contribute to our understanding of the ecophysiology of Pseudo-nitzschia spp. and may help to predict toxic events in the natural environment. PMID:26703627

  14. Effects of Organic and Inorganic Nitrogen on the Growth and Production of Domoic Acid by Pseudo-nitzschia multiseries and P. australis (Bacillariophyceae) in Culture.

    PubMed

    Martin-Jézéquel, Véronique; Calu, Guillaume; Candela, Leo; Amzil, Zouher; Jauffrais, Thierry; Séchet, Véronique; Weigel, Pierre

    2015-11-26

    Over the last century, human activities have altered the global nitrogen cycle, and anthropogenic inputs of both inorganic and organic nitrogen species have increased around the world, causing significant changes to the functioning of aquatic ecosystems. The increasing frequency of Pseudo-nitzschia spp. in estuarine and coastal waters reinforces the need to understand better the environmental control of its growth and domoic acid (DA) production. Here, we document Pseudo-nitzschia spp. growth and toxicity on a large set of inorganic and organic nitrogen (nitrate, ammonium, urea, glutamate, glutamine, arginine and taurine). Our study focused on two species isolated from European coastal waters: P. multiseries CCL70 and P. australis PNC1. The nitrogen sources induced broad differences between the two species with respect to growth rate, biomass and cellular DA, but no specific variation could be attributed to any of the inorganic or organic nitrogen substrates. Enrichment with ammonium resulted in an enhanced growth rate and cell yield, whereas glutamate did not support the growth of P. multiseries. Arginine, glutamine and taurine enabled good growth of P. australis, but without toxin production. The highest DA content was produced when P. multiseries grew with urea and P. australis grew with glutamate. For both species, growth rate was not correlated with DA content but more toxin was produced when the nitrogen source could not sustain a high biomass. A significant negative correlation was found between cell biomass and DA content in P. australis. This study shows that Pseudo-nitzschia can readily utilize organic nitrogen in the form of amino acids, and confirms that both inorganic and organic nitrogen affect growth and DA production. Our results contribute to our understanding of the ecophysiology of Pseudo-nitzschia spp. and may help to predict toxic events in the natural environment.

  15. Molecular phylogeny and taxonomic revision of the genus Wittrockiella (Pithophoraceae, Cladophorales), including the descriptions of W. australis sp. nov. and W. zosterae sp. nov.

    PubMed

    Boedeker, Christian; O'Kelly, Charles J; West, John A; Hanyuda, Takeaki; Neale, Adele; Wakana, Isamu; Wilcox, Mike D; Karsten, Ulf; Zuccarello, Giuseppe C

    2017-03-12

    Wittrockiella is a small genus of filamentous green algae that occurs in habitats with reduced or fluctuating salinities. Many aspects of the basic biology of these algae are still unknown and the phylogenetic relationships within the genus have not been fully explored. We provide a phylogeny based on three ribosomal markers (ITS, LSU and SSU rDNA) of the genus, including broad intraspecific sampling for W. lyallii and W. salina, recommendations for the use of existing names are made, and highlight aspects of their physiology and life cycle. Molecular data indicates that there are five species of Wittrockiella. Two new species, W. australis and W. zosterae, are described, both are endophytes. While W. lyallii and W. salina can be identified morphologically, there are no diagnostic morphological characters to distinguish between W. amphibia, W. australis and W. zosterae. A range of low molecular weight carbohydrates were analysed but proved to not be taxonomically informative. The distribution range of W. salina is extended to the Northern Hemisphere as this species has been found in brackish lakes in Japan. Furthermore it is shown that there are no grounds to recognise W. salina var. kraftii, which was described as an endemic variety from a freshwater habitat on Lord Howe Island, Australia. Culture experiments indicate that W. australis has a preference for growth in lower salinities over full seawater. For W. amphibia and W. zosterae sexual reproduction is documented, and the split of these species is possibly attributable to polyploidization. This article is protected by copyright. All rights reserved.

  16. Bioinformatic prediction of G protein-coupled receptor encoding sequences from the transcriptome of the foreleg, including the Haller's organ, of the cattle tick, Rhipicephalus australis.

    PubMed

    Munoz, Sergio; Guerrero, Felix D; Kellogg, Anastasia; Heekin, Andrew M; Leung, Ming-Ying

    2017-01-01

    The cattle tick of Australia, Rhipicephalus australis, is a vector for microbial parasites that cause serious bovine diseases. The Haller's organ, located in the tick's forelegs, is crucial for host detection and mating. To facilitate the development of new technologies for better control of this agricultural pest, we aimed to sequence and annotate the transcriptome of the R. australis forelegs and associated tissues, including the Haller's organ. As G protein-coupled receptors (GPCRs) are an important family of eukaryotic proteins studied as pharmaceutical targets in humans, we prioritized the identification and classification of the GPCRs expressed in the foreleg tissues. The two forelegs from adult R. australis were excised, RNA extracted, and pyrosequenced with 454 technology. Reads were assembled into unigenes and annotated by sequence similarity. Python scripts were written to find open reading frames (ORFs) from each unigene. These ORFs were analyzed by different GPCR prediction approaches based on sequence alignments, support vector machines, hidden Markov models, and principal component analysis. GPCRs consistently predicted by multiple methods were further studied by phylogenetic analysis and 3D homology modeling. From 4,782 assembled unigenes, 40,907 possible ORFs were predicted. Using Blastp, Pfam, GPCRpred, TMHMM, and PCA-GPCR, a basic set of 46 GPCR candidates were compiled and a phylogenetic tree was constructed. With further screening of tertiary structures predicted by RaptorX, 6 likely GPCRs emerged and the strongest candidate was classified by PCA-GPCR to be a GABAB receptor.

  17. Bioinformatic prediction of G protein-coupled receptor encoding sequences from the transcriptome of the foreleg, including the Haller’s organ, of the cattle tick, Rhipicephalus australis

    PubMed Central

    Munoz, Sergio; Guerrero, Felix D.; Kellogg, Anastasia; Heekin, Andrew M.

    2017-01-01

    The cattle tick of Australia, Rhipicephalus australis, is a vector for microbial parasites that cause serious bovine diseases. The Haller’s organ, located in the tick’s forelegs, is crucial for host detection and mating. To facilitate the development of new technologies for better control of this agricultural pest, we aimed to sequence and annotate the transcriptome of the R. australis forelegs and associated tissues, including the Haller's organ. As G protein-coupled receptors (GPCRs) are an important family of eukaryotic proteins studied as pharmaceutical targets in humans, we prioritized the identification and classification of the GPCRs expressed in the foreleg tissues. The two forelegs from adult R. australis were excised, RNA extracted, and pyrosequenced with 454 technology. Reads were assembled into unigenes and annotated by sequence similarity. Python scripts were written to find open reading frames (ORFs) from each unigene. These ORFs were analyzed by different GPCR prediction approaches based on sequence alignments, support vector machines, hidden Markov models, and principal component analysis. GPCRs consistently predicted by multiple methods were further studied by phylogenetic analysis and 3D homology modeling. From 4,782 assembled unigenes, 40,907 possible ORFs were predicted. Using Blastp, Pfam, GPCRpred, TMHMM, and PCA-GPCR, a basic set of 46 GPCR candidates were compiled and a phylogenetic tree was constructed. With further screening of tertiary structures predicted by RaptorX, 6 likely GPCRs emerged and the strongest candidate was classified by PCA-GPCR to be a GABAB receptor. PMID:28231302

  18. Growing Hemorrhagic Choroidal Fissure Cyst

    PubMed Central

    Gelal, Fazıl; Gurkan, Gokhan; Feran, Hamit

    2016-01-01

    Choroidal fissure cysts are often incidentally discovered. They are usually asymptomatic. The authors report a case of growing and hemorrhagic choroidal fissure cyst which was treated surgically. A 22-year-old female presented with headache. Cranial MRI showed a left-sided choroidal fissure cyst. Follow-up MRI showed that the size of the cyst had increased gradually. Twenty months later, the patient was admitted to our emergency department with severe headache. MRI and CT showed an intracystic hematoma. Although such cysts usually have a benign course without symptoms and progression, they may rarely present with intracystic hemorrhage, enlargement of the cyst and increasing symptomatology. PMID:26962426

  19. Universal properties of growing networks

    NASA Astrophysics Data System (ADS)

    Krapivsky, P. L.; Derrida, B.

    2004-09-01

    Networks growing according to the rule that every new node has a probability pk of being attached to k preexisting nodes, have a universal phase diagram and exhibit power-law decays of the distribution of cluster sizes in the non-percolating phase. The percolation transition is continuous but of infinite order and the size of the giant component is infinitely differentiable at the transition (though of course non-analytic). At the transition the average cluster size (of the finite components) is discontinuous.

  20. What a Pain! Kids and Growing Pains

    MedlinePlus

    ... What Happens in the Operating Room? What a Pain! Kids and Growing Pains KidsHealth > For Kids > What a Pain! Kids and ... something doctors call growing pains . What Are Growing Pains? Growing pains aren't a disease. You probably ...

  1. What a Pain! Kids and Growing Pains

    MedlinePlus

    ... dientes Video: Getting an X-ray What a Pain! Kids and Growing Pains KidsHealth > For Kids > What a Pain! Kids and ... something doctors call growing pains . What Are Growing Pains? Growing pains aren't a disease. You probably ...

  2. Long-term carbon storage and its recent loss in an estuarine Posidonia australis meadow (Albany, Western Australia)

    NASA Astrophysics Data System (ADS)

    Rozaimi, Mohammad; Lavery, Paul S.; Serrano, Oscar; Kyrwood, Danielle

    2016-03-01

    Oyster Harbour, on the south coast of Western Australia, supports 3.6-3.9 km2 of seagrass meadows, following the loss of approximately 2.8-3.1 km2 in the 1980s. This small area of prevailing meadows hold significant carbon stores accumulated over the past 3000 years. In this study, we sampled three sediment cores from a Posidonia australis meadow and analysed organic matter (OM), organic carbon (OC) and inorganic carbon (IC) contents in bulk sediments, and δ13C signatures of OM. The OM and OC contents (mean ± SE) in the cores were 9.07 ± 0.36% and 2.24 ± 0.05%, respectively. The mean IC content was 3.16 ± 0.17%. δ13C signatures of the sedimentary OM ranged from -10.01‰ to -13.28‰. Using a Bayesian isotopic mixing model, it is estimated that 57-67% of the OM in the seagrass sediments was derived from P. australis detrital matter. The total carbon (TC) stores in 150 cm-thick seagrass sediments averaged 27.92 kg TC m-2 (10.79 kg OC m-2 and 17.13 kg IC m-2). Based on radiocarbon dating, the mean sediment accumulation rate was 0.0494 cm yr-1, which led to a long-term TC accumulation rate of 8.92 g TC m-2 yr-1 (3.45 g OC m-2 yr-1 and 5.47 g IC m-2 yr-1). Based on historical seagrass cover (3.6-6.7 km2 during the 1960s to 1980s), the estimated TC stores in 150 cm-thick seagrass sediments at Oyster Harbour would have been 101-187 Gg TC. The eutrophication-driven loss of seagrasses during the 1980s resulted in the absence of OC accumulation capacity amounting to 280-310 Mg OC (over 29 years). The loss of seagrass area could also have resulted in the release of 37-41 Gg CO2, assuming that all of the OC in shallow sediment is remineralised after meadow disturbance. These results exemplify the importance of seagrasses meadows as important carbon sinks and the potential for losses of carbon stores due to ecosystem degradation.

  3. Organic geochemistry of resins from modern Agathis australis and Eocene resins from New Zealand: Diagenetic and taxonomic implications

    USGS Publications Warehouse

    Lyons, P.C.; Mastalerz, Maria; Orem, W.H.

    2009-01-01

    A maturation series of resins and fossil resins from New Zealand, ranging in age from Modern to Eocene and ranging from uncoalified to high volatile C bituminous coal, were analyzed by elemental, pyrolysis-gas chromatography (Py-GC), Fourier Transform infrared (FTir), and solid-state 13C nuclear magnetic resonance (13C NMR) techniques. For comparison, four resin samples from the Latrobe Valley, Australia, were analyzed. All of the resins and fossil resins of this study show very high H/C atomic ratios, and are characterized by dominant peaks in the 10-60??ppm range of solid-state 13C NMR spectra and prominent bands in the aliphatic stretching region (2800-3000??cm- 1) of FTir spectra, all indicating a highly aliphatic molecular structure. The 13C NMR and FTir data indicate a diterpenoid structure for these resins. There is an abrupt loss of oxygen that occurs at the Lignite A/Subbituminous C stage, which is attributed to a dramatic loss of carboxyl (COOH) from the diterpenoid molecule. This is a new finding in the diagenesis of resins. This important loss in oxygenated functional groups is attributed to a maturation change. Also, there is a progressive loss of exomethylene (CH2) groups with increasing degree of maturation, as shown by both 13C NMR and FTir data. This change has been noted by previous investigators. Exomethylene is absent in the fossil resins from the Eocene high volatile C bituminous coals. This progressive loss is characteristic of Class I resinites. FTir data indicate that the oxygenated functional groups are strong in all the resin samples except the fossil resin from high volatile C bituminous coal. This important change in oxygenated functional groups is attributed to maturation changes. The 13C NMR and FTir data indicate there are minor changes in the Agathis australis resin from the living tree and soil, which suggests that alteration of A. australis resins begins shortly after deposition in the soil for as little as 1000??years. The Morwell

  4. Release method and anatomical hook location: effects on short-term mortality of angler-caught Acanthopagrus australis and Argyrosomus japonicus.

    PubMed

    Butcher, Paul A; Broadhurst, Matt K; Reynolds, Darren; Reid, Dennis D; Gray, Charles A

    2007-02-08

    One field and 3 aquaria experiments were done to quantify the short-term mortality of yellowfin bream Acanthopagrus australis and mulloway Argyrosomus japonicus after being angled and subjected to 3 general handling treatments. Anglers were supplied with identical J-type hooks and asked to handle hooked fish by either (1) physically removing the hook or (2) cutting the line (5 cm from the mouth of the fish) and leaving the hook in. Some hooked A. japonicus were subjected to a third handling treatment where the line was cut underwater without exposing the fish to air. Technical and biological data were collected before all fish were released into sea cages and monitored for 5 d. Control fish were seined and similarly caged and monitored. Concentrations of plasma glucose and cortisol were collected from a sample of fish on the first and last day of the experiments. Significant predictors of mortality for both species involved the presence of blood at the mouth and an interaction between anatomical hook location and hook removal. A. australis and A. japonicus that had their ingested hooks removed experienced the greatest mortalities (87.5 and 72.7%, respectively). Typically, these fish suffered damage to their oesophagus, stomach wall and vital organs. Mortality rates of A. australis and A. japonicus were significantly decreased to 1.7 and 16%, respectively, when they were released with their lines cut, with some of these fish free of hooks after 5 d. In contrast, few mortalities occurred in either species when the hooks were removed or the lines cut on mouth-hooked fish or in A. japonicus when it was released with no air exposure. For A. australis, the field- and aquaria-based experiments provided comparable results in terms of identifying treatment-specific effects, but there were potential biases in rates of hook ingestion. Irrespective of the treatment of fish, all experiments caused physiological changes measured as elevations in either plasma cortisol or glucose

  5. Seasonal and diurnal variations in methane emissions from Wuliangsu Lake in arid regions of China

    NASA Astrophysics Data System (ADS)

    Duan, Xiaonan; Wang, Xiaoke; Mu, Yujing; Ouyang, Zhiyun

    CH 4 emissions have been widely studied in various wetlands, such as boreal peatlands, rice paddies, and tropical swamps. However, little investigation has been carried out for CH 4 emissions from lakes or wetlands in arid regions where these freshwaters play a vital role in providing ecosystem services for local people. To quantify the spatial and temporal variations of CH 4 flux and understand its key controlling factors in shallow lakes in arid regions of Western China, CH 4 fluxes from Wuliangsu Lake were measured at different vegetation zones and water depths with a static chamber technique during a growing season from April to October in 2003. Results showed that the average emission flux of CH 4 from submerged plant ( Potamogeton pectinatus) growing zones was 2.16 mg CH 4 m -2 h -1, which was 85.8% lower than that from emergent macrophyte ( Phragmites australis) growing zones. CH 4 emissions increased with increasing water depth in Phragmites Community. Significant seasonal and diurnal variations of CH 4 emission were observed for P. australis during the plant growth stage, for P. pectinatus growing zones, however, the variations were minor. In addition to vegetation cover and water depth, bottom silt temperature and light intensity were also important factors influencing seasonal and diurnal variations of CH 4 flux from Phargmites growing zone.

  6. How to grow great leaders.

    PubMed

    Ready, Douglas A

    2004-12-01

    Few leaders excel at both the unit and enterprise levels. More than ever, though, corporations need people capable of running business units, functions, or regions and focusing on broader company goals. It's up to organizations to develop leaders who can manage the inherent tensions between unit and enterprise priorities. Take the example of RBC Financial Group, one of the largest, most profitable companies in Canada. In the mid-1990's, RBC revamped its competitive strategy in a couple of ways. After the government announced that the Big Six banks in Canada could neither merge with nor acquire one another, RBC decided to grow through cross-border acquisitions. Additionally, because customers were starting to seek bundled products and services, RBC reached across its traditional stand-alone businesses to offer integrated solutions. These changes in strategy didn't elicit immediate companywide support. Instinctively, employees reacted against what would amount to a delicate balancing act: They would have to lift their focus out of their silos while continuing to meet unit goals. However, by communicating extensively with staff members, cross-fertilizing talent across unit boundaries, and targeting rewards to shape performance, RBC was able to cultivate rising leaders with the unit expertise and the enterprise vision to help the company fulfill its new aims. Growing such well-rounded leaders takes sustained effort because unit-enterprise tensions are quite real. Three common conditions reinforce these tensions. First, most organizational structures foster silo thinking and unimaginative career paths. Second, most companies lack venues for airing and resolving conflicts that arise when there are competing priorities. Third, many have misguided reward systems that pit unit performance against enterprise considerations. Such long-established patterns of organizational behavior are tough to break. Fortunately, as RBC discovered, people can be trained to think and work

  7. Uptake and distribution of N, P and heavy metals in three dominant salt marsh macrophytes from Yangtze River estuary, China.

    PubMed

    Quan, W M; Han, J D; Shen, A L; Ping, X Y; Qian, P L; Li, C J; Shi, L Y; Chen, Y Q

    2007-07-01

    We examined the variation in aboveground biomass accumulation and tissue concentrations of nitrogen (N), phosphorus (P), copper (Cu), zinc (Zn) and lead (Pb) in Phragmites australis (common reed), Spartina alterniflora (salt cordgrass), and Scirpus mariqueter throughout the growing season (April-October 2005), in order to determine the differences in net element accumulation and distribution between the three salt marsh macrophytes in the Yangtze River estuary, China. The aboveground biomass was significantly greater in the plots of S. alterniflora than in the plots of P. australis and S. mariqueter throughout the growing season (P<0.05). In August, the peak aboveground biomass was 1246+/-89 gDW/m(2), 2759+/-250 gDW/m(2) and 548+/-54 gDW/m(2) for P. australis, S. alterniflora and S. mariqueter, respectively. The concentrations of nutrients and heavy metals in plant tissues showed similar seasonal patterns. There was a steady decline in element concentrations of the aboveground tissues from April to October. Relative element concentrations in aboveground tissues were at a peak during the spring sampling intervals with minimum levels during the fall. But the concentrations of total nitrogen and total phosphorus in the belowground tissues were relatively constant throughout growing season. Generally, trace metal concentrations in the aboveground tissues of S. mariqueter was the highest throughout the growing season, and the metal concentrations of S. alterniflora tissues (aboveground and belowground) were greater than those of P. australis. Furthermore, the aboveground pools of nutrients and metals were consistently greater for S. alterniflora than for P. australis and S. mariqueter, which suggested that the rapid replacement of native P. australis and S. mariqueter with invasive S. alterniflora would significantly improve the magnitude of nutrient cycling and bioavailability of trace metals in the salt marsh and maybe transport more toxic metals into the water column

  8. Effects of Modified Handling on the Physiological Stress of Trawled-and-Discarded Yellowfin Bream (Acanthopagrus australis).

    PubMed

    Uhlmann, Sven Sebastian; Broadhurst, Matt Kenyon; Millar, Russell Brian

    2015-01-01

    Modified handling is often claimed to reduce (sub-)lethal impacts among organisms caught-and-released in fisheries. Improving welfare of discarded fish warrants investigation, when their survival is of both economic and ecological importance. In this study, juvenile yellowfin bream (Acanthopagrus australis) were trawled in an Australian penaeid fishery and then discarded after on-board sorting in either dry or water-filled (modified) trays and with delays in starting sorting of either 2 or 15 mins. Blood plasma cortisol, glucose and potassium were sampled immediately from some yellowfin bream, while others were placed into cages (with controls) and sampled after five days. Irrespective of their on-board handling, all trawled fish incurred a relatively high acute stress response (i.e. an increase in Mean ± SE cortisol from a baseline of <4 to 122.0 ± 14.9 ng/mL) that was mostly attributed to the trawling process, and exacerbated by variation in key parameters (low salinity, changes in water temperature and the presence of jellyfish Catostylus mosaicus in catches). When C. mosaicus was present, the potassium concentrations of fish sampled immediately after sorting were significantly elevated, possibly due to nematocyst contact and subsequent inhibition of ion pumps or cytolysis. Stress also increased during handling in response to warmer air temperatures and longer exposure. While most fish had substantially recovered by 120 hours after discarding, deploying selective trawls (to reduce jellyfish) for short periods and then quickly sorting catches in water would benefit discard welfare.

  9. The first report of otarine herpesvirus-1-associated urogenital carcinoma in a South American fur seal (Arctocephalus australis).

    PubMed

    Dagleish, M P; Barrows, M; Maley, M; Killick, R; Finlayson, J; Goodchild, R; Valentine, A; Saunders, R; Willoughby, K; Smith, K C; Stidworthy, M F

    2013-07-01

    Otarine herpesvirus (OtHV)-1-associated urogenital carcinoma has been well documented in the California sea lion (Zalophus californianus, CSL), but this is the first report of this tumour in a captive South American fur seal (Arctocephalus australis, SAFS). The gross and microscopical morphology of the tumour in the SAFS was identical to that described previously in CSLs and the tumour in the present case had metastasized within the urogenital tract and draining lymph nodes and to the lungs and one kidney. Immunohistochemistry revealed intra- and extracytoplasmic labelling of herpesvirus antigen in the cells of the tumour tissue and transitional epithelium of the urethra. OtHV-1 nucleic acids were detected within tumour tissue and from a urogenital swab by polymerase chain reaction. The ranges of these two species of pinniped do not overlap normally in the wild, suggesting that transmission of OtHV-1 probably occurred in captivity. This confirmed susceptibility of the SAFS to the development of OtHV-1-associated urogenital carcinoma suggests that all species of Otariidae should be screened for OtHV-1 infection prior to movement within and between zoological collections.

  10. The reproductive biology of a shallow water morid ( Salilota australis Günther, 1878), around the Falkland Islands

    NASA Astrophysics Data System (ADS)

    Brickle, Paul; Laptikhovsky, Vladimir; Arkhipkin, Alexander

    2011-07-01

    The reproductive biology of a shelf morid, red cod ( Salilota australis) was investigated in the Falkland Islands, in order to expand our knowledge of the reproductive strategy of this relatively unstudied family of fishes. Red cod spawn to the south and south-west of West Falkland between August and October. Length frequency and sex ratio data suggest that females arrive at the spawning grounds first. The greatest spawning activity occurred in early evening and this timing may be an adaptation to reduce predation on eggs. Ripe egg size varied from 0.95 to 1.26 mm and was not dependant on female size. There was no regulative atresia during maturation and the formation of fecundity and fecundity increased with increasing fish total length ( LT) from 300,000 (42-45 cm LT) to 4.5-9.0 million eggs (75-83 cm LT). The fecundity of most of the population was between 2 and 5 million eggs. Red cod releases small batches of eggs over the spawning period. Batch size ranged from 30,000-90,000 (39-42 cm LT) in smaller animals to 400,000-800,000 (>75 cm LT) in larger animals and the batch size of first spawners was significantly higher than for advanced spawners. The study allows us to discuss the evolutionary relationships between the Gadiformes.

  11. Echolocation in sympatric Peale's dolphins (Lagenorhynchus australis) and Commerson's dolphins (Cephalorhynchus commersonii) producing narrow-band high-frequency clicks.

    PubMed

    Kyhn, L A; Jensen, F H; Beedholm, K; Tougaard, J; Hansen, M; Madsen, P T

    2010-06-01

    An increasing number of smaller odontocetes have recently been shown to produce stereotyped narrow-band high-frequency (NBHF) echolocation clicks. Click source parameters of NBHF clicks are very similar, and it is unclear whether the sonars of individual NBHF species are adapted to specific habitats or the presence of other NBHF species. Here, we test whether sympatric NBHF species sharing the same habitat show similar adaptations in their echolocation clicks and whether their clicks display signs of character displacement. Wide-band sound recordings were obtained with a six-element hydrophone array from wild Peale's (Lagenorhynchus australis) and Commerson's (Cephalorhynchus commersonii) dolphins off the Falkland Islands. The centroid frequency was different between Commerson's (133+/-2 kHz) and Peale's (129+/-3 kHz) dolphins. The r.m.s. bandwidth was 12+/-3 kHz for both species. The source level was higher for Peale's dolphin (185+/-6 dB re 1 muPa p.-p.) than for Commerson's (177+/-5 dB re 1 muPa p.-p.). The mean directivity indexes were 25 dB for both species. The relatively low source levels in combination with the high directivity index may be an adaptation to reduce clutter when foraging in a coastal environment. We conclude that the small species-specific shifts in distribution of centroid frequencies around 130 kHz may reflect character displacement in otherwise-stereotyped NBHF clicks.

  12. Characterization of the faecal bacterial community of wild young South American (Arctocephalus australis) and Subantarctic fur seals (Arctocephalus tropicalis).

    PubMed

    Medeiros, Aline Weber; Giongo, Adriana; Valdez, Fernanda P; Blaese de Amorin, Derek; Tavares, Maurício; d'Azevedo, Pedro A; Franco, Ana Claudia; Frazzon, Jeverson; Frazzon, Ana P G

    2016-03-01

    The microbiota of wild marine mammals is poorly understood, perhaps due to the migratory habits of some species and the difficulty in obtaining samples. Using high-throughput sequencing, the present study examines the faecal bacterial community of wild young South American (Arctocephalus australis) and Subantarctic fur seals (A. tropicalis). Faecal samples from South American (n = 6) and Subantarctic fur seals (n = 4) found dead along the south coast of Brazil were collected. Sequences were assigned to taxa using the Ribosomal Database Project-Bayesian classifier. Diversity of the microbiota was assessed by categorization of sequence reads into operational taxonomic units. Results indicate that Firmicutes (88.556%-84.016%) was the predominant phylum in South American and Subantarctic fur seals. The distribution of Actinobacteria and Proteobacteria varied according to the fur seal species. Fusobacteria and Bacteroidetes represented less than 1% of the sequences. The most abundant order in both fur seals was Clostridiales (88.64% and 87.49%). Individual variable incidences were observed in the composition of family among the fur seals, though the families Lachnospiraceae, Peptostreptococcaceae, Ruminococcaceae and Coriobacteriaceae were more prevalent. This study provides insight into the faecal bacterial community of wild young South American and Subantarctic fur seals.

  13. Vocalizations produced by southern right whale (Eubalaena australis) mother-calf pairs in a calving ground off Brazil.

    PubMed

    Dombroski, Julia R G; Parks, Susan E; Groch, Karina R; Flores, Paulo A C; Sousa-Lima, Renata S

    2016-09-01

    Aiming to gather information on southern right whale (Eubalaena australis) mother-calf pairs' vocal behavior, archival acoustic recorders were deployed at a calving area off Brazil. Manual inspection of spectrograms revealed seven call classes: upcall, downcall, down-upcall, tonal variable, tonal constant, hybrid, and pulsive calls, which are consistent with those previously described for this species in Argentina. Gunshots and warbles, vocalizations described from other right whale species, were not detected. Mean values of start, end, maximum, minimum and peak frequencies, frequency bandwidth and duration were calculated for each call class. Start and end frequencies, frequency bandwidth and duration of upcalls recorded off Brazil were compared to those from other right whale populations and species. Only mean duration of upcalls from Brazil were significantly different from upcalls from all other populations. Differences in call duration may be driven by differences in demographic factors or background noise features among study areas. The repertoire characterization presented in this study will contribute to increase the utility of passive acoustic monitoring as a tool for conservation and research of southern right whales off Brazil as it provides important baseline information on the vocal behavior of this species.

  14. First chemical synthesis of a scorpion alpha-toxin affecting sodium channels: the Aah I toxin of Androctonus australis hector.

    PubMed

    M'Barek, Sarrah; Fajloun, Ziad; Cestèle, Sandrine; Devaux, Christiane; Mansuelle, Pascal; Mosbah, Amor; Jouirou, Besma; Mantegazza, Massimo; Van Rietschoten, Jurphaas; El Ayeb, Mohamed; Rochat, Hervé; Sabatier, Jean-Marc; Sampieri, François

    2004-11-01

    Aah I is a 63-residue alpha-toxin isolated from the venom of the Buthidae scorpion Androctonus australis hector, which is considered to be the most dangerous species. We report here the first chemical synthesis of Aah I by the solid-phase method, using a Fmoc strategy. The synthetic toxin I (sAah I) was renatured in DMSO-Tris buffer, purified and subjected to thorough analysis and comparison with the natural toxin. The sAah I showed physico-chemical (CD spectrum, molecular mass, HPLC elution), biochemical (amino-acid composition, sequence), immunochemical and pharmacological properties similar to those of the natural toxin. The synthetic toxin was recognized by a conformation-dependent monoclonal anti-Aah I antibody, with an IC50 value close to that for the natural toxin. Following intracerebroventricular injection, the synthetic and the natural toxins were similarly lethal to mice. In voltage-clamp experiments, Na(v) 1.2 sodium channel inactivation was inhibited by the application of sAah I or of the natural toxin in a similar way. This work describes a simple protocol for the chemical synthesis of a scorpion alpha-toxin, making it possible to produce structural analogues in time.

  15. Fast K(+) currents from cerebellum granular cells are completely blocked by a peptide purified from Androctonus australis Garzoni scorpion venom.

    PubMed

    Pisciotta, M; Coronas, F I; Bloch, C; Prestipino, G; Possani, L D

    2000-09-29

    A novel peptide was purified from the venom of the scorpion Androctonus australis Garzoni (abbreviated Aa1, corresponding to the systematic number alpha KTX4.4). It contains 37 amino acid residues, has a molecular mass of 3850 Da, is closely packed by three disulfide bridges and a blocked N-terminal amino acid. This peptide selectively affects the K(+) currents recorded from cerebellum granular cells. Only the fast activating and inactivating current, with a kinetics similar to I(A)-type current, is completely blocked by the addition of low micromolar concentrations (K(i) value of 150 nM) of peptide Aa1 to the external side of the cell preparation. The blockade is partially reversible in our experimental conditions. Aa1 blocks the channels in both the open and the closed states. The blockage is test potential independent and is not affected by changes in the holding potential. The kinetics of the current are not affected by the addition of Aa1 to the preparation; it means that the block is a simple 'plugging mechanism', in which a single toxin molecule finds a specific receptor site in the external vestibule of the K(+) channel and thereby occludes the outer entry to the K(+) conducting pore.

  16. Red fox ( Vulpes vulpes L.) favour seed dispersal, germination and seedling survival of Mediterranean Hackberry ( Celtis australis L.)

    NASA Astrophysics Data System (ADS)

    Juan, Traba; Sagrario, Arrieta; Jesús, Herranz; Cristina, Clamagirand M.

    2006-07-01

    Seeds of the Mediterranean Hackberry Celtis australis are often encountered in fox faeces. In order to evaluate the effect of gut transit on the size of seeds selected, the rates and speed of germination and on the survival of the seedlings, Mediterranean Hackberry seeds from fox faeces were germinated in a greenhouse. The results were compared with those of seeds taken from ripe, uneaten fruits. Fox-dispersed seeds were smaller and lighter than the control ones and had higher (74% vs. 57%) and more rapid germination (74.5 days vs. 99.2 days). Seedlings from fox-dispersed seeds showed significantly greater survival by the end of the study period (74.1% vs. 43.6%) than the control ones. Survival in seedlings from fox-dispersed seeds was related to germination date, late seedlings showing poorer survival. This relationship was not observed away in the control seedlings. Seed mass did not affect seedling survival. Seedling arising from fox-dispersed seeds grew faster than control ones. These results suggest that fox can play a relevant role as seed disperser of Mediterranean Hackberry.

  17. Chemical Characterization and Anti-Oomycete Activity of Laureliopsis philippianna Essential Oils against Saprolegnia parasitica and S. australis.

    PubMed

    Madrid, Alejandro; Godoy, Patricio; González, Sebastián; Zaror, Luis; Moller, Alejandra; Werner, Enrique; Cuellar, Mauricio; Villena, Joan; Montenegro, Iván

    2015-05-05

    Laureliopsis philippiana (Looser) R. Schodde (Monimiaceae) is a native tree widespread in the forest areas in the south of Chile and Argentina, known for its medicinal properties and excellent wood. The aim of this study was to evaluate the chemical composition of L. philippiana leaf and bark essential oils (EOs) using gas chromatography-mass spectrometry (GC-MS), and to quantify its anti-oomycete activity, specifically against Saprolegnia parasitica and S. australis. Only six components were identified in leaf EO, 96.92% of which are phenylpropanoids and 3.08% are terpenes. As for bark EO, 29 components were identified, representing 67.61% for phenylpropanoids and 32.39% for terpenes. Leaf EO was characterized mainly by safrole (96.92%) and β-phellandrene (1.80%). Bark EO was characterized mainly by isosafrole (30.07%), safrole (24.41%), eucalyptol (13.89%), methyleugenol (7.12%), and eugenol (6.01%). Bark EO has the most promising anti-Saprolegnia activity, with a minimum inhibition concentration (MIC) value of 30.0 µg/mL against mycelia growth and a minimum fungicidal concentration (MFC) value of 50.0 μg/mL against spores; for leaf EO, the MIC and MFC values are 100 and 125 µg/mL, respectively. These findings demonstrate that bark EO has potential to be developed as a remedy for the control of Saprolegnia spp. in aquaculture.

  18. The cocoon of the fossorial frog Cyclorana australis functions primarily as a barrier to water exchange with the substrate.

    PubMed

    Reynolds, Stephen J; Christian, Keith A; Tracy, Christopher R

    2010-01-01

    Studies of evaporative water loss using streams of dry air in the laboratory have demonstrated reduced rates in various taxa of cocooned frogs. However, because the cocoon is formed in subterranean burrows with humid microclimates and no air flow, loss of water by evaporation is likely to be negligible. In contrast, although potentially important, the influence of the cocoon on water exchange with the soil surface has not been characterized. In dry soils, there is a sizable water potential gradient between the frog and the soil; hence, we hypothesized that cocoons would play a role in reducing liquid water loss to dry substrates. Individuals of the burrowing frog Cyclorana australis (Hylidae: Pelodryadinae) were induced to form cocoons in the laboratory. On semisolid agar-solute substrates across a range of water potentials, the hygroscopic cocoon absorbed small but similar amounts of moisture. With the cocoon removed, the frogs gained or lost water, depending on the direction of the frog-substrate water potential difference. Plasma osmolality of cocooned frogs was significantly higher than in hydrated frogs. Because cocooned frogs did not exchange significant amounts of water at either high (wet) or low (dry) substrate water potentials, we conclude that the cocoon of fossorial frogs acts as a physical barrier that breaks the continuity between frog and substrate. We contend that the primary function of the cocoon is to prevent liquid water loss to drying clay and loam soils, rather than to prevent subterranean evaporative water loss.

  19. Growing plants on atoll soils

    SciTech Connect

    Stone, E L; Migvar, L; Robison, W L

    2000-02-16

    Many years ago people living on atolls depended entirely on foods gathered from the sea and reefs and grown on land. Only a few plants, such as coconut (ni), Pandanus (bob), and arrowroot (mok-mok), could be grown on the lower rainfall atolls, although adequate groundwater conditions also allowed taro (iaraj, kotak, wot) to be cultivated. On higher rainfall atolls, breadfruit (ma) was a major food source, and banana (binana, kepran), lime (laim), and taros (iaraj, kotak, wot) could be grown. The early atoll populations were experts in growing plants that were vital to sustaining their nutrition requirements and to providing materials for thatch, basketry, cordage, canoe construction, flowers, and medicine. They knew which varieties of food plants grew well or poorly on their atolls, how to propagate them, and where on their atoll they grew best. They knew the uses of most native plants and what the various woods were well suited for. Many varieties of Pandanus (bob) and breadfruit (ma) grew well with high rainfall, but only a few produced well on drier atolls. Such information had been passed down through the generations although some of it has been lost in the last century. Today there are new plants and new varieties of existing plants that can be grown on atolls. There are also new materials and information on how to grow both the old and new plants more effectively. However, there are also introduced weeds and pests to control. Today, there is also an acute need to grow more of the useful plants adapted to atolls. Increasing numbers of people living on an atoll without an equal increase in income or food production stretches the available food supplies. Much has been written about the poor conditions for plant growth on atolls. As compared with many places in the world where crops are grown, however, atolls can provide some highly favorable conditions. For instance, the driving force for plant growth is sunlight, and on atolls light is abundant throughout the

  20. [Growing old differently: Transdisciplinary perspective].

    PubMed

    Zimmermann, H-P

    2015-04-01

    Growing old differently: the phrase is intended to call something other to mind than merely the fact that images and forms of old age and aging have multiplied and diversified to an enormous extent. The suggestion put forward here is that otherness (as opposed to mere differences) should be positively reinforced. In other words, it is not just a matter of noting different forms of old age and aging but more than this, of seeking out opportunities for aging differently. In order to explore this, the article follows an older strand of theory, which has recently come to be frequently quoted in gerontology: the phenomenology of difference as reasoned analytically by Lévinas and Sartre and applied to gerontology by Améry and de Beauvoir. Here, opportunities for aging crucially depend on the way we look at it, how we observe and describe it and not least, how gerontology frames it. A distinction is made between two perspectives and their associated consequences for old age: alienation and alterity. Alienation means looking at old age above all as a disconcerting "other", as a perplexing, problematic deviation from the norm of vitality. Alterity, by contrast, refers to different options for living life in old age: options to be explored and opened up in contradistinction to cultural or academic alienation. Not least, the article appeals for diversity in scholarly approaches and for cross-disciplinary perspectives.

  1. Growing and evolving soft robots.

    PubMed

    Rieffel, John; Knox, Davis; Smith, Schuyler; Trimmer, Barry

    2014-01-01

    Completely soft and flexible robots offer to revolutionize fields ranging from search and rescue to endoscopic surgery. One of the outstanding challenges in this burgeoning field is the chicken-and-egg problem of body-brain design: Development of locomotion requires the preexistence of a locomotion-capable body, and development of a location-capable body requires the preexistence of a locomotive gait. This problem is compounded by the high degree of coupling between the material properties of a soft body (such as stiffness or damping coefficients) and the effectiveness of a gait. This article synthesizes four years of research into soft robotics, in particular describing three approaches to the co-discovery of soft robot morphology and control. In the first, muscle placement and firing patterns are coevolved for a fixed body shape with fixed material properties. In the second, the material properties of a simulated soft body coevolve alongside locomotive gaits, with body shape and muscle placement fixed. In the third, a developmental encoding is used to scalably grow elaborate soft body shapes from a small seed structure. Considerations of the simulation time and the challenges of physically implementing soft robots in the real world are discussed.

  2. Esophageal malignancy: A growing concern

    PubMed Central

    Chai, Jianyuan; Jamal, M Mazen

    2012-01-01

    Esophageal cancer is mainly found in Asia and east Africa and is one of the deadliest cancers in the world. However, it has not garnered much attention in the Western world due to its low incidence rate. An increasing amount of data indicate that esophageal cancer, particularly esophageal adenocarcinoma, has been rising by 6-fold annually and is now becoming the fastest growing cancer in the United States. This rise has been associated with the increase of the obese population, as abdominal fat puts extra pressure on the stomach and causes gastroesophageal reflux disease (GERD). Long standing GERD can induce esophagitis and metaplasia and, ultimately, leads to adenocarcinoma. Acid suppression has been the main strategy to treat GERD; however, it has not been proven to control esophageal malignancy effectively. In fact, its side effects have triggered multiple warnings from regulatory agencies. The high mortality and fast growth of esophageal cancer demand more vigorous efforts to look into its deeper mechanisms and come up with better therapeutic options. PMID:23236223

  3. Draft Genome Sequence of Pseudomonas sp. Strain BMS12, a Plant Growth-Promoting and Protease-Producing Bacterium, Isolated from the Rhizosphere Sediment of Phragmites karka of Chilika Lake, India.

    PubMed

    Mishra, Samir R; Panda, Ananta Narayan; Ray, Lopamudra; Sahu, Neha; Mishra, Gayatri; Jadhao, Sudhir; Suar, Mrutyunjay; Adhya, Tapan Kumar; Rastogi, Gurdeep; Pattnaik, Ajit Kumar; Raina, Vishakha

    2016-06-30

    We report the 4.51 Mb draft genome of Pseudomonas sp. strain BMS12, a Gram-negative bacterium in the class of Gammaproteobacteria, isolated from the rhizospheric sediment of Phragmites karka, an invasive weed in Chilika Lake, Odisha, India. The Pseudomonas sp. strain BMS12 is capable of producing proteases and is also an efficient plant growth promoter that can be useful for various phytoremedial and industrial applications.

  4. Draft Genome Sequence of Acinetobacter sp. Strain BMW17, a Cellulolytic and Plant Growth-Promoting Bacterium Isolated from the Rhizospheric Region of Phragmites karka of Chilika Lake, India.

    PubMed

    Mishra, Samir R; Ray, Lopamudra; Panda, Ananta Narayan; Sahu, Neha; Xess, Sonal S; Jadhao, Sudhir; Suar, Mrutyunjay; Adhya, Tapan Kumar; Rastogi, Gurdeep; Pattnaik, Ajit Kumar; Raina, Vishakha

    2016-06-30

    We report the 3.16 Mb draft genome of Acinetobacter sp. strain BMW17, a Gram-negative bacterium in the class of Gammaproteobacteria, isolated from the rhizospheric region of Phragmites karka, an invasive weed in Chilika Lake, Odisha, India. The strain BMW17(T) is capable of degrading cellulose and is also an efficient plant growth promoter that can be useful for various phytoremedial and commercial applications.

  5. Draft Genome Sequence of Acinetobacter sp. Strain BMW17, a Cellulolytic and Plant Growth-Promoting Bacterium Isolated from the Rhizospheric Region of Phragmites karka of Chilika Lake, India

    PubMed Central

    Mishra, Samir R.; Ray, Lopamudra; Panda, Ananta Narayan; Sahu, Neha; Xess, Sonal S.; Jadhao, Sudhir; Suar, Mrutyunjay; Adhya, Tapan Kumar; Rastogi, Gurdeep; Pattnaik, Ajit Kumar

    2016-01-01

    We report the 3.16 Mb draft genome of Acinetobacter sp. strain BMW17, a Gram-negative bacterium in the class of Gammaproteobacteria, isolated from the rhizospheric region of Phragmites karka, an invasive weed in Chilika Lake, Odisha, India. The strain BMW17T is capable of degrading cellulose and is also an efficient plant growth promoter that can be useful for various phytoremedial and commercial applications. PMID:27365343

  6. How High Do Sandbars Grow?

    NASA Astrophysics Data System (ADS)

    Alexander, J. S.; McElroy, B. J.

    2015-12-01

    Bar forms in wide sandy rivers store sediment, control channel hydraulics, and are fundamental units of riverine ecosystems. Bar form height is often used as a measure of channel depth in ancient fluvial deposits and is also a crucially important measure of habitat quality in modern rivers. In the Great Plains of North America, priority bird species use emergent bars to nest, and sandbar heights are a direct predictor of flood hazard for bird nests. Our current understanding of controls on bar height are limited to few datasets and ad hoc observations from specific settings. We here examine a new dataset of bar heights and explore models of bar growth. We present bar a height dataset from the Platte and Niobrara Rivers in Nebraska, and an unchannelized reach of the Missouri River along the Nebraska-South Dakota border. Bar height data are normalized by flow frequency, and we examine parsimonious statistical models between expected controls (depth, stage, discharge, flow duration, work etc.) and maximum bar heights. From this we generate empirical-statistical models of maximum bar height for wide, sand-bedded rivers in the Great Plains of the United States and rivers of similar morphology elsewhere. Migration of bar forms is driven by downstream slip-face additions of sediment sourced from their stoss sides, but bars also sequester sediment and grow vertically and longitudinally. We explore our empirical data with a geometric-kinematic model of bar growth driven by sediment transport from smaller-scale bedforms. Our goal is to understand physical limitations on bar growth and geometry, with implications for interpreting the rock record and predicting physically-driven riverine habitat variables.

  7. REMOTE DETECTION OF INVASSIVE AND OPPORTUNISTIC PLANT SPECIES IN GREAT LAKES COASTAL WETLANDS

    EPA Science Inventory

    Invasive and opportunistic plant species have been associated with wetland disturbance. Increases in the abundance of plant species such as common reed (Phragmites australis) in coastal Great Lakes wetlands are hypothesized to occur with shifts toward drier hydrologic regimes, fr...

  8. REMOTE DETENTION OF INVASIVE AND OPPORTUNISTIC PLANT SPECIES IN GREAT LAKES COASTAL WETLANDS

    EPA Science Inventory

    Invasive and opportunistic plant species have been associated with wetland disturbance. Increases in the abundance of plant species such as common reed (Phragmites australis) in coastal Great Lakes wetlands are hypothesized to occur with shifts toward drier hydrologic regimes, fr...

  9. ACCURACY ASSESSMENTS OF AIRBORNE HYSPERSPECTRAL DATA FOR MAPPING OPPORTUNISTIC PLANT SPECIES IN FRESHWATER COASTAL WETLANDS

    EPA Science Inventory

    Airbome hyperspectral data were used to detect dense patches of Phragmites australis, a native opportunist plant species, at the Pointe Mouillee coastal wetland complex (Wayne and Monroe Counties, Michigan). This study provides initial results from one of thirteen coastal wetland...

  10. El Nino Continues to Grow

    NASA Technical Reports Server (NTRS)

    2002-01-01

    The latest image from NASA's Jason oceanography satellite, taken during a 10-day collection cycle ending December 2, 2002, shows the Pacific dominated by two significant areas of higher-than-normal sealevel (warmer ocean temperatures). In the central equatorial Pacific, the large area of higher than normal sea surface heights(warmer than normal sea surface temperatures) associated with growing El Nino conditions has recently migrated eastward toward the coast of South America. Meanwhile, the influence of the 20- to 30-year larger than El Nino/La Nina pattern called the Pacific Decadal Oscillation continues to create warm, higher-than-normal sea-surface heights in the north Pacific that are connected in a warm horseshoe pattern with the western and southern Pacific. Sea-surface heights are a measure of how much heat is stored in the ocean below. This heat influences both present weather and future planetary climate events.

    The image shows red areas in the north Pacific and at the equator that are about 10 centimeters (4 inches) above normal; white areas indicate sea surface heights between 14 and 32 centimeters (6 to 13 inches) above normal. These regions contrast with the western tropical Pacific, where lower-than-normal sea levels (blue areas) have developed that are between 5 and 13 centimeters (2 and 5 inches) below normal, while purple areas range from 14 to 18 centimeters (6 to 7 inches) below normal. Along the equator, the red sea surface heights equate to sea surface temperature departures greater than one degree Celsius (two degrees Fahrenheit) and the white sea surface heights are sea surface temperatures 1.5 to 2.5 degrees Celsius(three to five degrees Fahrenheit) above normal.

    The U.S. portion of the Jason mission is managed by JPL for NASA's Earth Science Enterprise, Washington, D.C. Research on Earth's oceans using Jason and other space-based capabilities is conducted by NASA's Earth Science Enterprise to better understand and protect our

  11. Evidence for lamprey GnRH-I and -III-like molecules in the brains of the southern hemisphere lampreys Geotria australis and Mordacia mordax.

    PubMed

    Sower, S A; McGregor, A J; Materne, O L; Chase, C; Potter, I; Joss, J

    2000-11-01

    The present study has characterized gonadotropic releasing hormone (GnRH)-like molecules in the brains of representatives of the two southern hemisphere families of lampreys, Geotriidae and Mordaciidae. Chromatographic and immunocytochemical evidence showed that the brains of Geotria australis and Mordacia mordax contain two forms of GnRH-like molecules. These two forms correspond to lamprey GnRH-I and -III, which were first sequenced from the brain of the anadromous sea lamprey Petromyzon marinus, a representative of the family Petromyzontidae that is found only in the northern hemisphere. In chromatographic studies (HPLC) using lamprey GnRH-I and -III antiserum, two early eluting GnRH forms coeluted with synthetic lamprey GnRH-I and -III standards. Our studies thus indicate that, despite their apparently long period of separation, the three families of extant lampreys have each retained both of the lamprey GnRH (-I and -III forms) molecules. Moreover, immunocytochemical localization of lamprey GnRH indicated that the pattern of its distribution in the adult brain of at least one of these southern hemisphere lampreys (G. australis) is similar to that previously described for P. marinus. Distribution of GnRH in the brain of larval G. australis was not as extensive as that in larval P. marinus, which may account for the later gonadal development in the former species. The fact that lamprey GnRH-I and -III are the dominant GnRH forms in all three families of lampreys implies that these neurohormones have an ancient origin.

  12. Transcriptome and Degradome of microRNAs and Their Targets in Response to Drought Stress in the Plants of a Diploid and Its Autotetraploid Paulownia australis

    PubMed Central

    Niu, Suyan; Wang, Yuanlong; Zhao, Zhenli; Deng, Minjie; Cao, Lin; Yang, Lu; Fan, Guoqiang

    2016-01-01

    MicroRNAs (miRNAs) are small, non-coding RNAs that play vital roles in plant growth, development, and stress response. Increasing numbers of studies aimed at discovering miRNAs and analyzing their functions in plants are being reported. In this study, we investigated the effect of drought stress on the expression of miRNAs and their targets in plants of a diploid and derived autotetraploid Paulownia australis. Four small RNA (sRNA) libraries and four degradome libraries were constructed from diploid and autotetraploid P. australis plants treated with either 75% or 25% relative soil water content. A total of 33 conserved and 104 novel miRNAs (processing precision value > 0.1) were identified, and 125 target genes were identified for 36 of the miRNAs by using the degradome sequencing. Among the identified miRNAs, 54 and 68 were differentially expressed in diploid and autotetraploid plants under drought stress (25% relative soil water content), respectively. The expressions of miRNAs and target genes were also validated by quantitative real-time PCR. The results showed that the relative expression trends of the randomly selected miRNAs were similar to the trends predicted by Illumina sequencing. And the correlations between miRNAs and their target genes were also analyzed. Furthermore, the functional analysis showed that most of these miRNAs and target genes were associated with plant development and environmental stress response. This study provided molecular evidence for the possible involvement of certain miRNAs in the drought response and/or tolerance in P. australis, and certain level of differential expression between diploid and autotetraploid plants. PMID:27388154

  13. SURVEY FOR INFECTIOUS DISEASE IN THE SOUTH AMERICAN FUR SEAL (ARCTOCEPHALUS AUSTRALIS) POPULATION AT PUNTA SAN JUAN, PERU.

    PubMed

    Jankowski, Gwen; Adkesson, Michael J; Saliki, Jeremiah T; Cárdenas-Alayza, Susana; Majluf, Patricia

    2015-06-01

    The Peruvian population of the South American fur seal ( Arctocephalus australis ) is a distinct evolutionarily significant unit that is endangered. One of the largest rookeries for this species in Peru is located within the Punta San Juan marine protected area (15°22'S, 75°12'W). To better understand the current health status of this population, exposure to 10 pinniped pathogens was evaluated in adult female fur seals (n=29) via serology and polymerase chain reaction (PCR) techniques in November 2010. The results suggest this population is naïve to canine and phocine distemper viruses (serum neutralization test), five Leptospira interrogans serovars (microscopic agglutination test), and Brucella canis (card test). Indirect fluorescent antibody testing for Toxoplasma gondii , Neospora caninum , and Sarcocystis neurona was also uniformly negative. PCR testing of nasal swabs using previously described Mycoplasma spp. primers was positive in 37.9% (11/29) of samples. One animal was positive via card test for Brucella abortus , whereas 53.7% (15/28) were positive or suspect using a marine Brucella competitive enzyme-linked immunosorbent assay. Antibody to phocine herpesvirus-1 (PHV-1) was identified in 85.7% (24/28) of the sampled population by serum neutralization testing. Overall, exposure to Mycoplasma spp., Brucella spp., and PHV-1 was observed, but results demonstrated low to no exposure to many key pinniped pathogens. The expansion of human populations, agriculture, and industry along the Peruvian coast may lead to increased pathogen exposure from human, domestic, and wild animal sources. The naïve nature of this key population of South American fur seals raises concerns about potential risk for disease outbreaks.

  14. Soil CO2 efflux in an old-growth southern conifer forest (Agathis australis) - magnitude, components and controls

    NASA Astrophysics Data System (ADS)

    Schwendenmann, Luitgard; Macinnis-Ng, Cate

    2016-08-01

    Total soil CO2 efflux and its component fluxes, autotrophic and heterotrophic respiration, were measured in a native forest in northern Aotearoa-New Zealand. The forest is dominated by Agathis australis (kauri) and is on an acidic, clay rich soil. Soil CO2 efflux, volumetric soil water content and soil temperature were measured bi-weekly to monthly at 72 sampling points over 18 months. Trenching and regression analysis was used to partition total soil CO2 efflux into heterotrophic and autotrophic respiration. The effect of tree structure was investigated by calculating an index of local contribution (Ic, based on tree size and distance to the measurement location) followed by correlation analysis between Ic and total soil CO2 efflux, root biomass, litterfall and soil characteristics. The measured mean total soil CO2 efflux was 3.47 µmol m-2 s-1. Autotrophic respiration accounted for 25 % (trenching) or 28 % (regression analysis) of total soil CO2 efflux. Using uni- and bivariate models showed that soil temperature was a poor predictor of the temporal variation in total soil CO2 efflux (< 20 %). In contrast, a stronger temperature sensitivity was found for heterotrophic respiration (around 47 %). We found significant positive relationships between kauri tree size (Ic) and total soil CO2 efflux, root biomass and mineral soil CN ratio within 5-6 m of the sampling points. Using multiple regression analysis revealed that 97 % of the spatial variability in total soil CO2 efflux in this kauri-dominated stand was explained by root biomass and soil temperature. Our findings suggest that biotic factors such as tree structure should be investigated in soil carbon related studies.

  15. In situ O2 dynamics in submerged Isoetes australis: varied leaf gas permeability influences underwater photosynthesis and internal O2

    PubMed Central

    Pedersen, Ole; Pulido, Cristina; Rich, Sarah Meghan; Colmer, Timothy David

    2011-01-01

    A unique type of vernal pool are those formed on granite outcrops, as the substrate prevents percolation so that water accumulates in depressions when precipitation exceeds evaporation. The O2 dynamics of small, shallow vernal pools with dense populations of Isoetes australis were studied in situ, and the potential importance of the achlorophyllous leaf bases to underwater net photosynthesis (PN) and radial O2 loss to sediments is highlighted. O2 microelectrodes were used in situ to monitor pO2 in leaves, shallow sediments, and water in four vernal pools. The role of the achlorophyllous leaf bases in gas exchange was evaluated in laboratory studies of underwater PN, loss of tissue water, radial O2 loss, and light microscopy. Tissue and sediment pO2 showed large diurnal amplitudes and internal O2 was more similar to sediment pO2 than water pO2. In early afternoon, sediment pO2 was often higher than tissue pO2 and although sediment O2 declined substantially during the night, it did not become anoxic. The achlorophyllous leaf bases were 34% of the surface area of the shoots, and enhanced by 2.5-fold rates of underwater PN by the green portions, presumably by increasing the surface area for CO2 entry. In addition, these leaf bases would contribute to loss of O2 to the surrounding sediments. Numerous species of isoetids, seagrasses, and rosette-forming wetland plants have a large proportion of the leaf buried in sediments and this study indicates that the white achlorophyllous leaf bases may act as an important area of entry for CO2, or exit for O2, with the surrounding sediment. PMID:21841181

  16. CHEMICAL AND PHYSICAL CONDITIONS IN MOLECULAR CLOUD CORE DC 000.4-19.5 (SL42) IN CORONA AUSTRALIS

    SciTech Connect

    Hardegree-Ullman, E.; Whittet, D. C. B.; Harju, J.; Juvela, M.; Sipilae, O.; Hotzel, S.

    2013-01-20

    Chemical reactions in starless molecular clouds are heavily dependent on interactions between gas phase material and solid phase dust and ices. We have observed the abundance and distribution of molecular gases in the cold, starless core DC 000.4-19.5 (SL42) in Corona Australis using data from the Swedish ESO Submillimeter Telescope. We present column density maps determined from measurements of C{sup 18}O (J = 2-1, 1-0) and N{sub 2}H{sup +} (J = 1-0) emission features. Herschel data of the same region allow a direct comparison to the dust component of the cloud core and provide evidence for gas phase depletion of CO at the highest extinctions. The dust color temperature in the core calculated from Herschel maps ranges from roughly 10.7 to 14.0 K. This range agrees with the previous determinations from Infrared Space Observatory and Planck observations. The column density profile of the core can be fitted with a Plummer-like density distribution approaching n(r) {approx} r {sup -2} at large distances. The core structure deviates clearly from a critical Bonnor-Ebert sphere. Instead, the core appears to be gravitationally bound and to lack thermal and turbulent support against the pressure of the surrounding low-density material: it may therefore be in the process of slow contraction. We test two chemical models and find that a steady-state depletion model agrees with the observed C{sup 18}O column density profile and the observed N(C{sup 18}O) versus A{sub V} relationship.

  17. Anomalous colour in Neotropical mammals: a review with new records for Didelphis sp. (Didelphidae, Didelphimorphia) and Arctocephalus australis (Otariidae, Carnivora).

    PubMed

    Abreu, M S L; Machado, R; Barbieri, F; Freitas, N S; Oliveira, L R

    2013-02-01

    Anomalous colourations occur in many tropical vertebrates. However, they are considered rare in wild populations, with very few records for the majority of animal taxa. We report two new cases of anomalous colouration in mammals. Additionally, we compiled all published cases about anomalous pigmentation registered in Neotropical mammals, throughout a comprehensive review of peer reviewed articles between 1950 and 2010. Every record was classified as albinism, leucism, piebaldism or eventually as undetermined pigmentation. As results, we report the new record of a leucistic specimen of opossum (Didelphis sp.) in southern Brazil, as well as a specimen of South American fur seal (Arctocephalus australis) with piebaldism in Uruguay. We also found 31 scientific articles resulting in 23 records of albinism, 12 of leucism, 71 of piebaldism and 92 records classified as undetermined pigmentation. Anomalous colouration is apparently rare in small terrestrial mammals, but it is much more common in cetaceans and michrochiropterans. Out of these 198 records, 149 occurred in cetaceans and 30 in bats. The results related to cetaceans suggest that males and females with anomolous pigmentation are reproductively successful and as a consequence their frequencies are becoming higher in natural populations. In bats, this result can be related to the fact these animals orient themselves primarily through echolocation, and their refuges provide protection against light and predation. It is possible that anomalous colouration occurs more frequently in other Neotropical mammal orders, which were not formally reported. Therefore, we encourage researchers to publish these events in order to better understand this phenomenon that has a significant influence on animal survival.

  18. A Mössbauer spectroscopic study of the forms of storage iron in the larval and adult stages of the lamprey, Geotria australis

    NASA Astrophysics Data System (ADS)

    St. Pierre, T. G.; Harris, L.; Webb, J.; Macey, D. J.

    1992-04-01

    The principal forms of storage-iron in the lamprey, Geotria australis, are haemosiderin in the nephric fold of the larval animal and ferritin in the liver of the adult. Mössbauer spectroscopy of the larval haemosiderin showed that about half of the iron was in the form of ferrihydrite (5Fe2O3.9H2O) with the remainder being in the form of a non-crystalline iron oxyhydroxide, suggesting two modes of biomineralization. The cores of the adult liver ferritin gave spectral parameters indicating the iron to be predominantly in the form of ferrihydrite with about 10% being in a non-crystalline phase.

  19. Moisturizing effect of serine-loaded solid lipid nanoparticles and polysaccharide-rich extract of root Phragmites communis incorporated in hydrogel bases.

    PubMed

    Barua, Sonia; Kim, Hyeongmin; Hong, Seong-Chul; Yoo, Seung-Yup; Shin, Dohyun; Lee, Chung-Lyol; Na, Seon-Jeong; Kim, Yeong Hyo; Jo, Kanghee; Yun, Gyiae; Kim, Joong-Hark; Sohn, Uy Dong; Lee, Jaehwi

    2017-02-01

    This study evaluated the moisturizing effect of serine-loaded solid lipid nanoparticles (serine-SLN) and polysaccharide-rich reed (Phragmites communis) root extract (RRE) incorporated in hydrogel bases. The hydrogels with serine-SLN and/or RRE were carefully applied on the volar forearm of human volunteers. Their moisturizing efficacy was evaluated by monitoring conductance values using a skin surface hygrometer. The values of the area under the normalized conductance-time curve (AUCC) were developed and compared as a parameter for the water holding capacity of the skin. Hydrogels with serine-SLN did not significantly moisturize the skin, while hydrogel containing 0.25% RRE produced a significant increase in the moisture content of the skin. However, adding more than 0.25% of RRE into the hydrogel base decreased the moisturizing effect due to the marked reduction of viscosity. Significantly enhanced moisturizing effect was observed with the hydrogel containing 0.25% RRE and 3% serine-SLN, with AUCC increased 2.21 times compared to than blank hydrogel. The results imply that effective delivery of serine into the skin is possible using lipid-based nanocarriers and RRE, which could be a promising strategy to moisturize the skin effectively.

  20. Enhancement removal of endocrine-disrupting pesticides and nitrogen removal in a biofilm reactor coupling of biodegradable Phragmites communis and elastic filler for polluted source water treatment.

    PubMed

    Feng, Lijuan; Yang, Guangfeng; Zhu, Liang; Xu, Xiangyang; Gao, Feng; Mu, Jun; Xu, Yanmei

    2015-01-01

    The coupling of conventional elastic filler and solid carbon source of Phragmites communis (P. communis) as the biofilm support was applied in a biofilm system for treating polluted source water containing nitrogen and trace endocrine-disrupting pesticides (cypermethrin and chlorpyrifos). Results showed that removal efficiencies of TN and EDPs were improved with addition of 3.6kg P. communis/m(3) in the biofilm system. Meanwhile, the uniform distribution of P. communis favored simultaneously nitrogen and organics removal but not to trace EDPs compared with non-uniform distribution of P. communis. The biofilm on elastic filler was mainly responsible for the nitrification with NH4(+)-N oxidation efficiency of 82.9±1.5%. Poor nitrification with NH4(+)-N oxidation efficiency of 36.3±6.1% but effective denitrification with a TN removal efficiency of 56.5±2.0% were obtained by the biofilm on P. communis. Cypermethrin was mainly removed via adsorption and microbial degradation, and chlorpyrifos removal mostly depended on the microbial degradation in biofilm system.

  1. [Dry matter storage and water soluble sugar content in different age classes rhizomes of Phragmites communis population in dry land habitat of Songnen Plain of China].

    PubMed

    Yang, Yun-Fei; Zhang, Bao-Tian; Tian, Shang-Yi

    2008-09-01

    Based on the investigation and measurement of Phragmites communis in a single dominant species community in dry land habitat of Songnen Plain, the seasonal variation of dry matter storage and water soluble sugar content in different age classes rhizomes at three growth stages were analyzed. The results showed that at all growth stages, younger age class rhizomes had lower dry matter storage and water soluble sugar content, and there was an obvious difference between younger and older age classes. The dry matter storage and water soluble sugar content in younger age class rhizomes increased rapidly with growth season, and the difference between younger and older age classes reduced gradually. In the whole growth season, all the rhizomes of six age classes kept up the activities in nutrient consumption, re-storage and even overcompensating storage, and the activities of younger age class rhizomes were much higher. The dry matter storage and water soluble sugar content in older age class rhizomes increased with year. There existed extremely significant differences (P < 0.01) in the dry matter storage within and among different age class rhizomes, and the difference was larger within age classes than among age classes. Significant differences (P < 0.05) in water soluble sugar content were also observed among different age class rhizomes. The dry matter storage and water soluble sugar content in P. communis rhizomes increased in quadratic with increasing age class.

  2. Repellent effects of Melaleuca alternifolia (tea tree) oil against cattle tick larvae (Rhipicephalus australis) when formulated as emulsions and in β-cyclodextrin inclusion complexes.

    PubMed

    Yim, Wei Tsun; Bhandari, Bhesh; Jackson, Louise; James, Peter

    2016-07-30

    Rhipicephalus australis (formerly Boophilus microplus) is a one host tick responsible for major economic loss in tropical and subtropical cattle production enterprises. Control is largely dependent on the application of acaricides but resistance has developed to most currently registered chemical groups. Repellent compounds that prevent initial attachment of tick larvae offer a potential alternative to control with chemical toxicants. The repellent effects of Melaleuca alternifolia oil (TTO) emulsions and two β-cyclodextrin complex formulations, a slow release form (SR) and a modified faster release form (FR), were examined in a series of laboratory studies. Emulsions containing 4% and 5% TTO applied to cattle hair in laboratory studies completely repelled ascending tick larvae for 24h whereas 2% and 3% formulations provided 80% protection. At 48h, 5% TTO provided 78% repellency but lower concentrations repelled less than 60% of larvae. In a study conducted over 15 days, 3% TTO emulsion applied to cattle hair provided close to 100% repellency for 2 days, but then protection fell to 23% by day 15. The FR formulation gave significantly greater repellency than the emulsion and the SR formulation from day 3 until the end of the study (P<0.05), providing almost complete repellency at day 3 (99.5%), then decreasing over the period of the study to 49% repellency at day 15. Proof of concept is established for the use of appropriately designed controlled-release formulations to extend the period of repellency provided by TTO against R. australis larvae.

  3. THE SPITZER SURVEY OF INTERSTELLAR CLOUDS IN THE GOULD BELT. III. A MULTI-WAVELENGTH VIEW OF CORONA AUSTRALIS

    SciTech Connect

    Peterson, Dawn E.; Bourke, Tyler L.; Forbrich, Jan; Patten, Brian M.; Caratti o Garatti, Alessio; Gutermuth, Robert A.; Joergensen, Jes K.; Allen, Lori E.; Dunham, Michael M.; Harvey, Paul M.; Evans, Neal J.; MerIn, Bruno; Chapman, Nicholas L.; Cieza, Lucas A.; Huard, Tracy L.; Knez, Claudia; Prager, Brian

    2011-06-01

    We present Spitzer Space Telescope IRAC and MIPS observations of a 0.85 deg{sup 2} field including the Corona Australis (CrA) star-forming region. At a distance of 130 pc, CrA is one of the closest regions known to be actively forming stars, particularly within its embedded association, the Coronet. Using the Spitzer data, we identify 51 young stellar objects (YSOs) in CrA which include sources in the well-studied Coronet cluster as well as sources distributed throughout the molecular cloud. Twelve of the YSOs discussed are new candidates, one of which is located in the Coronet. Known YSOs retrieved from the literature are also added to the list, and a total of 116 candidate YSOs in CrA are compiled. Based on these YSO candidates, the star formation rate is computed to be 12 M{sub sun} Myr{sup -1}, similar to that of the Lupus clouds. A clustering analysis was also performed, finding that the main cluster core, consisting of 68 members, is elongated (having an aspect ratio of 2.36), with a circular radius of 0.59 pc and mean surface density of 150 pc{sup -2}. In addition, we analyze outflows and jets in CrA by means of new CO and H{sub 2} data. We present 1.3 mm interferometric continuum observations made with the Submillimeter Array (SMA) covering R CrA, IRS 5, IRS 7, and IRAS 18595-3712 (IRAS 32). We also present multi-epoch H{sub 2} maps and detect jets and outflows, study their proper motions, and identify exciting sources. The Spitzer and ISAAC/VLT observations of IRAS 32 show a bipolar precessing jet, which drives a CO(2-1) outflow detected in the SMA observations. There is also clear evidence for a parsec-scale precessing outflow, which is east-west oriented and originates in the SMA 2 region and likely driven by SMA 2 or IRS 7A.

  4. Intestinal helminth fauna of the South American sea lion Otaria flavescens and fur seal Arctocephalus australis from northern Patagonia, Argentina.

    PubMed

    Hernández-Orts, J S; Montero, F E; Juan-García, A; García, N A; Crespo, E A; Raga, J A; Aznar, F J

    2013-09-01

    We report on the intestinal helminth fauna of 56 South American sea lions, Otaria flavescens, and 5 South American fur seals, Arctocephalus australis, from northern Patagonia, Argentina. A total of 97,325 helminth specimens were collected from sea lions. Gravid individuals were represented by 6 species of parasites: 1 digenean (Ascocotyle (Ascocotyle) patagoniensis), 1 cestode (Diphyllobothrium spp.), 3 nematodes (Uncinaria hamiltoni, Contracaecum ogmorhini s.s., Pseudoterranova cattani) and 1 acanthocephalan (Corynosoma australe). In addition, third-stage larvae of 2 nematodes (Contracaecum sp. and Anisakis sp. type I) and 3 juvenile acanthocephalans (Andracantha sp., Profilicollis chasmagnathi and Corynosoma cetaceum) were also collected. Andracantha sp., C. ogmorhini s.s. and P. chasmagnathi represent new host records. A total of 1516 helminth specimens were collected from fur seals. Gravid individuals were represented by three species of parasites, namely, Diphyllobothrium spp., C. ogmorhini s.s. and C. australe. In addition, larvae of Contracaecum sp. and P. cattani, juveniles of C. cetaceum and immature cestodes (Tetrabothriidae gen. sp.) were also collected. Corynosoma australe was the most prevalent and abundant parasite in both hosts, accounting for >90% of all specimens. Sea lions and furs seals from northern Patagonia harbour the intestinal helminth communities that could be predicted for otariids, i.e. the combination of species of the genera Corynosoma, Diphyllobothrium, Pseudoterranova, Contracaecum and, in pups, Uncinaria. Additionally, both species of otariid are apparently unsuitable hosts (i.e. non-hosts) for as many as five parasite taxa. The inclusion or exclusion of these species affects estimation of species richness at both component community (11 versus 6 species in sea lions; 7 versus 3 species in fur seals) and infracommunity (mean: 3.1 versus 2.6 in sea lions; 2.2 versus 1.7 species) levels. Information about the reproductive status of

  5. The draft genome sequence of Mangrovibacter sp. strain MP23, an endophyte isolated from the roots of Phragmites karka.

    PubMed

    Behera, Pratiksha; Vaishampayan, Parag; Singh, Nitin K; Mishra, Samir R; Raina, Vishakha; Suar, Mrutyunjay; Pattnaik, Ajit K; Rastogi, Gurdeep

    2016-09-01

    Till date, only one draft genome has been reported within the genus Mangrovibacter. Here, we report the second draft genome shotgun sequence of a Mangrovibacter sp. strain MP23 that was isolated from the roots of Phargmites karka (P. karka), an invasive weed growing in the Chilika Lagoon, Odisha, India. Strain MP23 is a facultative anaerobic, nitrogen-fixing endophytic bacteria that grows optimally at 37 °C, 7.0 pH, and 1% NaCl concentration. The draft genome sequence of strain MP23 contains 4,947,475 bp with an estimated G + C content of 49.9% and total 4392 protein coding genes. The genome sequence has provided information on putative genes that code for proteins involved in oxidative stress, uptake of nutrients, and nitrogen fixation that might offer niche specific ecological fitness and explain the invasive success of P. karka in Chilika Lagoon. The draft genome sequence and annotation have been deposited at DDBJ/EMBL/GenBank under the accession number LYRP00000000.

  6. Growing Organic Crystals By The Czochralski Method

    NASA Technical Reports Server (NTRS)

    Shields, Angela; Frazier, Donald O.; Penn, Benjamin G.; Aggarwal, M. D.; Wang, W. S.

    1994-01-01

    Apparatus grows high-quality single crystals of organic compounds by Czochralski method. In Czochralski process, growing crystal lifted from middle of molten material without touching walls. Because of low melting temperatures of organic crystals, glass vessels usable. Traditional method for inorganic semiconductors adapted to optically nonlinear organic materials.

  7. Using Inorganic Crystals To Grow Protein Crystals

    NASA Technical Reports Server (NTRS)

    Shlichta, Paul J.; Mcpherson, Alexander A.

    1989-01-01

    Solid materials serve as nucleating agents. Protein crystals induced by heterogeneous nucleation and in some cases by epitaxy to grow at lower supersaturations than needed for spontaneous nucleation. Heterogeneous nucleation makes possible to grow large, defect-free single crystals of protein more readily. Such protein crystals benefits research in biochemistry and pharmacology.

  8. Growing Vegetables. People on the Farm.

    ERIC Educational Resources Information Center

    Department of Agriculture, Washington, DC. Office of Governmental and Public Affairs.

    This booklet, one in a series about life on modern farms, describes farm operations and some activities in the lives of six vegetable farmers throughout the United States. The booklet visits the tomato growing of Carl Schneider and his partners and the lettuce growing farm of Norman Martella, both in California. It then includes brief accounts of…

  9. Geometric Growing Patterns: What's the Rule?

    ERIC Educational Resources Information Center

    Hourigan, Mairéad; Leavy, Aisling

    2015-01-01

    While within a geometric repeating pattern, there is an identifiable core which is made up of objects that repeat in a predictable manner, a geometric growing pattern (also called visual or pictorial growing patterns in other curricula) "is a pattern that is made from a sequence of figures [or objects] that change from one term to the next in…

  10. Growing single crystals in silica gel

    NASA Technical Reports Server (NTRS)

    Rubin, B.

    1970-01-01

    Two types of chemical reactions for crystal growing are discussed. The first is a metathetical reaction to produce calcium tartrate tetrahydrate crystals, the second is a decomplexation reaction to produce cuprous chloride crystals.

  11. Plants growing in Apollo 15 lunar material

    NASA Technical Reports Server (NTRS)

    1971-01-01

    A close view of germ free plants - lettuce (left), tomato (right center and left center) and citrus (right). This type of testing is an effort at the Manned Spacecraft Center (MSC) to grow germ-free plants.

  12. FLUCTUATING MOTOR FORCES BEND GROWING MICROTUBULES

    PubMed Central

    Shekhar, Nandini; Neelam, Srujana; Wu, Jun; Ladd, Anthony JC; Dickinson, Richard B.; Lele, Tanmay P.

    2013-01-01

    Despite their rigidity, microtubules in living cells bend significantly during polymerization resulting in greater curvature than can be explained by thermal forces alone. However, the source of the non-thermal forces that bend growing microtubules remains obscure. We analyzed the motion of microtubule tips in NIH-3T3 fibroblasts expressing EGFP-EB1, a fluorescent +TIP protein that specifically binds to the growing ends of microtubules. We found that dynein inhibition significantly reduced the deviation of the growing tip from its initial trajectory. Inhibiting myosin modestly reduced tip fluctuations, while simultaneous myosin and dynein inhibition caused no further decrease in fluctuations compared to dynein inhibition alone. Our results can be interpreted with a model in which dynein linkages play a key role in generating and transmitting fluctuating forces that bend growing microtubules. PMID:24039637

  13. Visualization of airflow growing soap bubbles

    NASA Astrophysics Data System (ADS)

    Al Rahbi, Hamood; Bock, Matthew; Ryu, Sangjin

    2016-11-01

    Visualizing airflow inside growing soap bubbles can answer questions regarding the fluid dynamics of soap bubble blowing, which is a model system for flows with a gas-liquid-gas interface. Also, understanding the soap bubble blowing process is practical because it can contribute to controlling industrial processes similar to soap bubble blowing. In this study, we visualized airflow which grows soap bubbles using the smoke wire technique to understand how airflow blows soap bubbles. The soap bubble blower setup was built to mimic the human blowing process of soap bubbles, which consists of a blower, a nozzle and a bubble ring. The smoke wire was placed between the nozzle and the bubble ring, and smoke-visualized airflow was captured using a high speed camera. Our visualization shows how air jet flows into the growing soap bubble on the ring and how the airflow interacts with the soap film of growing bubble.

  14. Responses of enzymatic antioxidants and non-enzymatic antioxidants in the cyanobacterium Microcystis aeruginosa to the allelochemical ethyl 2-methyl acetoacetate (EMA) isolated from reed (Phragmites communis).

    PubMed

    Hong, Yu; Hu, Hong-Ying; Xie, Xing; Li, Feng-Min

    2008-08-25

    Macrophytic allelochemicals are considered an environment-friendly and promising alternative to control algal bloom. However, studies examining the potential mechanisms of inhibitory allelochemicals on algae are few. The allelochemical ethyl 2-methyl acetoacetate (EMA), isolated from reed (Phragmites communis), was a strong allelopathic inhibitor on the growth of Microcystis aeruginosa. EMA-induced antioxidant responses were investigated in the cyanobacterium M. aeruginosa to understand the mechanism of EMA inhibition on algal growth. The activities of enzymatic antioxidants superoxide dismutase (SOD) and catalase (CAT), and the contents of non-enzymatic antioxidants reduced glutathione (GSH) and ascorbic acid (AsA) of M. aeruginosa cells were analyzed after treatments with different concentrations of EMA. Exposure of M. aeruginosa to EMA caused changes in enzyme activities and contents of non-enzymatic antioxidants in different manners. The decrease in SOD activity occurred first after 4 h of EMA exposure, and more markedly after 40 h. CAT activity did not change after 4 h of EMA exposure, but increased obviously after 40 h. The contents of AsA and GSH were increased greatly by EMA after 4 h. After 60 h, low EMA concentrations still increased the CAT activity and the contents of AsA and GSH, but high EMA concentrations started to impose a marked suppression on them. EMA increased dehydroascorbate (DHAsA) and oxidized glutathione (GSSG) contents during all exposure times. After 60 h, the regeneration rates of AsA and GSH (represented by the AsA/DHAsA ratio and GSH/GSSG ratio, respectively) were reduced by high EMA concentrations. These results suggest that the activation of CAT and the availability of AsA and GSH at early exposure are important to counteract the oxidative stress induced by EMA, and the inactivation of SOD may be crucial to the growth inhibition of M. aeruginosa by EMA.

  15. Application of patent bio-rack wetland system using Phragmites sp. for domestic wastewater treatment in the presence of high total dissolved solids (TDS) and heavy metal salts.

    PubMed

    Valipour, Alireza; Raman, V Kalyan; Ghole, V S

    2011-07-01

    The quality of water recourses is degrading due to improper wastewater management. The aim of this study is to examine the potential of bio-rack system for treatment of domestic wastewater in the presence of high total dissolved solids (TDS) and heavy metal salts. The bio-rack is a modified wetland system incorporated with the advantages of phytoremediation and attached growth microbial process. The bio-rack is void of the soil strata based root zone system and in lieu a support matrix is provided to enrich the micro flora. The studies indicate that, Phragmites sp. can tolerate TDS up to 9000 mg/L in the bio-rack. The heavy metal removal is a function of phytoaccumulation or phytoextraction, which can lead to morphological deformity if heavy metals exceed the saturation limit of 786 and 5760 mg/kg Cd, 854 and 9280 mg/kg Cu, 639 and 4720 mg/kg Ni, 1187 and 7516 mg/kg Zn, in shoots and roots respectively. The reduction in TDS is marginal (14%) at the highest tolerable limit whereas the heavy metal reduction is 68%, 69%, 67%, 71% for Cd, Cu, Ni and Zn respectively at the outlet of the treatment system. The sewage treatment performance of the bio-rack system for all other parameters is estimated as 75 % Chemical Oxygen Demand (COD), 86 % Biological Oxygen Demand (BOD5), 27% Total Dissolved Solids (TDS), 73% Total Suspended Solids (TSS), 9% chlorides, 70% ammonia nitrogen (NH3-N), 32% phosphate (PO4-P), 92% most probable number (MPN) and 93% total viable count (TVC) reduction.

  16. [Dynamics of bud flow and bud bank of Phragmites communis population in dry land habitat of alkalinized meadow in the Songnen Plains of China].

    PubMed

    Yang, Yunfei; Wei, Chunyan; Zhang, Baotian; Liu, Bao

    2005-05-01

    In the dry land habitat of alkalinized meadow in Songnen Plains, the rhizomes of Phragmites communis population are distributed in different depths of one meter soil layer, which usually live for 6 years and a few for 7-9 years or even longer. Based on the investigation of their buds, a "bud flow" model of the population was established, and the method for estimating the dynamics of its bud bank storage, i.e., adding the input rate of 1st year age-class rhizome buds to the storage rate of other age-classes dormant buds in the bank, was put forward. The results showed that the input rate of the bud bank increased with plant growth seasons while the burgeoned output rate exhibited a decreasing trend, whereas the output rate of the dead remained at a low level on the whole. By the end of September in the early dormant period, the input rate of the bud bank was as 2.04 times as its output rate, and the dormant buds of each age-class manifested a steady burgeoned output. Quantitative analysis indicated that the burgeoned output rate of dormant buds increased by 11% each year. In another word, 11% of different age-classes dormant buds would germinate and form one-year class new rhizomes. The top of one-year class new rhizomes would develop to ramets in the next year, which would transport nutrients to nearby old-age rhizomes, and thus, maintain the vitality of old-age class rhizomes.

  17. Evaluation of the giant reed (Arundo donax) in horizontal subsurface flow wetlands for the treatment of dairy processing factory wastewater.

    PubMed

    Idris, Shaharah Mohd; Jones, Paul L; Salzman, Scott A; Croatto, George; Allinson, Graeme

    2012-09-01

    Two emergent macrophytes, Arundo donax and Phragmites australis, were established in experimental horizontal subsurface flow (HSSF), gravel-based constructed wetlands (CWs) and challenged by treated dairy processing factory wastewater with a median electrical conductivity of 8.9 mS cm(-1). The hydraulic loading rate was tested at 3.75 cm day(-1). In general, the plants grew well during the 7-month study period, with no obvious signs of salt stress. The major water quality parameters monitored (biological oxygen demand (BOD), suspended solids (SS) and total nitrogen (TN) but not total phosphorus) were generally improved after the effluent had passed through the CWs. There was no significance different in removal efficiencies between the planted beds and unplanted gravel beds (p > 0.007), nor was there any significant difference in removal efficiencies between the A. donax and P. australis beds for most parameters. BOD, SS and TN removal in the A. donax and P. australis CWs was 69, 95 and 26 % and 62, 97 and 26 %, respectively. Bacterial removal was observed but only to levels that would allow reuse of the effluent for use on non-food crops under Victorian state regulations. As expected, the A. donax CWs produced considerably more biomass (37 ± 7.2 kg wet weight) than the P. australis CWs (11 ± 1.4 kg wet weight). This standing crop equates to approximately 179 and 68 tonnes ha(-1) year(-1) biomass (dry weight) for A. donax and P. australis, respectively (assuming a 250-day growing season and single-cut harvest). The performance similarity of the A. donax and P. australis planted CWs indicates that either may be used in HSSF wetlands treating dairy factory wastewater, although the planting of A. donax provides additional opportunities for secondary income streams through utilisation of the biomass produced.

  18. Method for Growing Plants Aeroponically 1

    PubMed Central

    Zobel, Richard W.; Del Tredici, Peter; Torrey, John G.

    1976-01-01

    A simple, inexpensive system for growing plants with their roots bathed in nutrient mist is described. The aeroponics system uses a spinner from a home humidifier to propel nutrient solution into a polyethylene-lined plywood box atop which plants are supported on plastic light-fixture “egg crating.” Success in growing a number of herbaceous and woody species, including nodulated legumes and nonlegumes, is reported. Images PMID:16659479

  19. "Explosively growing" vortices of unstably stratified atmosphere

    NASA Astrophysics Data System (ADS)

    Onishchenko, O. G.; Horton, W.; Pokhotelov, O. A.; Fedun, V.

    2016-10-01

    A new type of "explosively growing" vortex structure is investigated theoretically in the framework of ideal fluid hydrodynamics. It is shown that vortex structures may arise in convectively unstable atmospheric layers containing background vorticity. From an exact analytical vortex solution the vertical vorticity structure and toroidal speed are derived and analyzed. The assumption that vorticity is constant with height leads to a solution that grows explosively when the flow is inviscid. The results shown are in agreement with observations and laboratory experiments

  20. Plant invasion impacts on the gross and net primary production of the salt marsh on eastern coast of China: Insights from leaf to ecosystem

    NASA Astrophysics Data System (ADS)

    Ge, Zhen-Ming; Guo, Hai-Qiang; Zhao, Bin; Zhang, Li-Quan

    2015-01-01

    exotic Spartina alterniflora from North America has been rapidly invading the entire Chinese coast, while the impacts of plant invasion on the gross (GPP) and net primary production (NPP) of the coastal salt marshes were less known. In this study, we investigated the photosynthetic performance, leaf characteristics, and primary production of the exotic C4 grass and the dominant native C3 grass (Phragmites australis) in two marsh mixtures (equipped with eddy covariance systems) in the Yangtze Estuary. The light-saturated photosynthetic rate and annual peak leaf area index (LAI) of S. alterniflora was higher than that of P. australis throughout the growing season. The leaf nitrogen content of P. australis declined sharper during the latter growing season than that of S. alterniflora. The leaf-to-canopy production model with species-specific (C3 and C4 types) parameterizations could reasonably simulate the daily trends and annual GPP amount against the 3 year flux measurements from 2005 to 2007, and the modeled NPP agreed with biomass measurements from the two species during 2012. The percentage contributions of GPP between S. alterniflora and P. australis were on average 5.82:1 and 2.91:1 in the two mixtures, respectively. The annual NPP amounts from S. alterniflora were higher by approximately 1.6 times than that from P. australis. Our results suggested that higher photosynthesis efficiency, higher LAI, and longer growing season resulted in greater GPP and NPP in the exotic species relative to the native species. The rapid expansion rate of S. alterniflora further made it the leading contributor of primary production in the salt marsh.

  1. Why we cannot grow a human arm.

    PubMed

    Ricci, John L

    2013-11-01

    There are several significant issues that prevent us from growing a human arm now, or within the next 10-20 years. From a tissue engineering perspective, while we can grow many of the components necessary for construction of a human arm, we can only grow them in relatively small volumes, and when scaled up to large volumes we lack the ability to develop adequate blood/nerve supply. From a genetic engineering perspective, we will probably never be able to turn on the specific genes necessary to "grow an arm" unless it is attached to a fetus and this presents enormous ethical issues related to farming of human organs and structures. Perhaps the most daunting problem facing the transplantation of a tissue engineered or transplanted arm is that of re-innervation of the structure. Since the sensory and motor nerve cells of the arm are located outside of the structure, re-innervation requires those nerves to regenerate over relatively large distances to repopulate the nervous system of the arm. This is something with which we have had little success. We can grow repair parts, but "growing an arm" presents too many insurmountable problems. The best we could possibly do with tissue engineering or genetic engineering would be the equivalent of a fetal arm and the technical problems, costs, and ethical hurdles are enormous. A more likely solution is a functional, permanent, neuroelectronically-controlled prosthesis. These are nearly a reality today.

  2. The Corona Australis Complex.

    NASA Astrophysics Data System (ADS)

    Vaile, Roberta Anne

    What began as a HI study of the CrA star formation region has grown to incorporate the following: (1) a detailed investigation of the HI content of the CrA dark cloud; (2) an extensive molecular survey of the CrA dark cloud, from which the CrA molecular abundances were determined and compared to those of other Galactic environments; (3) an extensive HI survey of the CrA complex, which was compared to the established Galactic distributions in and near the region; (4) an examination of the extent and nature of the CrA IVCs, components of gas at intermediate, anomalous velocities; (5) an investigation of the correlations which may exist between the features of the CrA region; and (6) an evaluation of where the CrA complex fits within the framework of our understanding of the Galaxy. A review of our perceptions of the Galactic structure is contained in Chapter I. The established state of knowledge of the CrA dark cloud region--chiefly, that of a region of young and on-going star formation--is given in Chapter II. The observational studies of the CrA dark cloud region specifically are presented in Chapter III. The HI survey of the CrA complex is presented in Chapter IV, with the CrA IVCs results presented in Chapter V. A comparison of the CrA HI structure with nearby Galactic features suggests that the CrA complex--exemplified by the T_ {rm A} morphology given as a frontispiece and in Figure 4.1--is a coherently -moving HI structure falling subject to the Rayleigh-Taylor, Kelvin-Helmholtz, flute and Parker hydrodynamic and magnetohydrodynamic instabilities under the Galactic gravitational and differential rotation forces. As the distance to the CrA IVCs still remains speculative, no definitive identity for the CrA IVCs was established. Considering the whole, the CrA complex was interpreted as a feature triggered by the Sco-Cen association, possibly a late-comer to the Lindblad Ring and possibly a result of the Tau-Gem events. The similarities with the Oph northern complex suggest that the CrA and Oph complexes may share a common origin. The subsequent evolution of the CrA complex may be explained by a relatively simple application of the effects of gravity and a magnetic field.

  3. Description of Paeon asymboli n. sp. (Copepoda: Sphyriidae), parasitic on Asymbolus spp. (catsharks) and a new host record for P. australis Kabata, 1993.

    PubMed

    Turner, T B; Kyne, P M; Bennett, M B

    2003-11-01

    Paeon asymboli n. sp. (Copepoda: Sphyriidae) is described and illustrated from two female specimens taken from the gills of a grey spotted catshark Asymbolus analis (Ogilby) and an orange spotted catshark A. rubiginosus (Last, Gomon & Gledhill) (Scyliorhinidae) from off southeastern Queensland, Australia. The key features for identification are: a pear-shaped trunk, longer than it is wide, along with a cephalothorax characterised by two large ventral papillae, projecting laterally and supporting a number of secondary lobes; a single mid-line, sub-conical papilla located antero-dorsal to the ventral papillae; an anterior surface bearing two prominent stalked papillae; and an absence of posterolateral lobular processes. P. australis Kabata, 1993 is recorded for the first time from the eastern shovelnose ray Aptychotrema rostrata (Shaw & Nodder) (Rhinobatidae).

  4. Dietary supplementation with purified mulberry (Morus australis Poir) anthocyanins suppresses body weight gain in high-fat diet fed C57BL/6 mice.

    PubMed

    Wu, Tao; Qi, Xueming; Liu, Yan; Guo, Jun; Zhu, Ruiyu; Chen, Wei; Zheng, Xiaodong; Yu, Ting

    2013-11-01

    We present our experiment about adding anthocyanins to the daily food of mice. Three kinds of anthocyanins (cyanidin-3-glucoside, cyanidin-3-rutinoside and pelargonidin-3-glucoside) purified from Chinese mulberry (Morus australis Poir) were evaluated for suppressing body weight gain of the male C57BL/6 mice fed with high-fat diet (HFD). The results from a 12-week experiment show that consumption of purified mulberry anthocyanins (MACN) of 40 or 200mg/kg can significantly inhibit body weight gain, reduce the resistance to insulin, lower the size of adipocytes, attenuate lipid accumulation and decrease the leptin secretion. Thus, dietary supplementation with MACN can protect against body weight gain of the diet-induced obese mice.

  5. Antimicrobial resistance and virulence factor gene profiles of Enterococcus spp. isolates from wild Arctocephalus australis (South American fur seal) and Arctocephalus tropicalis (Subantarctic fur seal).

    PubMed

    Santestevan, Naiara Aguiar; de Angelis Zvoboda, Dejoara; Prichula, Janira; Pereira, Rebeca Inhoque; Wachholz, Guilherme Raffo; Cardoso, Leonardo Almansa; de Moura, Tiane Martin; Medeiros, Aline Weber; de Amorin, Derek Blaese; Tavares, Maurício; d'Azevedo, Pedro Alves; Franco, Ana Claudia; Frazzon, Jeverson; Frazzon, Ana Paula Guedes

    2015-12-01

    Enterococci are natural inhabitants of the gastrointestinal tracts in humans and animals. Epidemiological data suggest that enterococci are important reservoirs of antimicrobial resistant genes that may be transmitted from other bacterial species The aim of this study was to investigate the species composition, antimicrobial resistance and virulence genes in enterococci recovered from fecal samples of wild Arctocephalus australis and A. tropicalis found dead along the South Coast of Brazil. From a total of 43 wild fur seals, eleven were selected for this study. Phenotypic and genotypic characterizations were used to classify Enterococcus species. Strains were tested for susceptibility to 10 antibiotics, presence of ace, gelE, asa, cylA, tet(L), tet(M) and erm(B) genes by PCR, and genetic variability using RAPD-PCR. Among the 50 enterococci isolated, 40% were Enterococcus faecalis, 40% E. hirae, 12% E. casseliflavus and 8 % other enterococcal species. Resistance profiles were observed to erythromycin, nitrofurantoin, tetracycline, norfloxacin and ciprofloxacin. The prevalence of virulence genes was ace (68%), gelE (54%), asa (22%) and cylA (4%). In erythromycin- and tetracycline strains, erm(B) and tet(M) were detected, respectively. The RAPD-PCR demonstrated a close phylogenetic relationship between the enterococci isolated from A. australis and A. tropicalis. In conclusion, different enterococcus species showing antimicrobial resistance and virulence determinates were isolated from fecal samples of fur seals. Antibiotic resistant strains in these animals could be related within food chain and aquatic pollutants or linked to environmental resistome, and demonstrates the potential importance of these animals as reservoirs and disseminators of such determinants in marine environmental.

  6. Growing pains: contemporary knowledge and recommended practice

    PubMed Central

    Evans, Angela M

    2008-01-01

    Background Leg pain in children, described as growing pains, is a frequent clinical presentation seen by an array of health care professionals. Described since 1823, growing pains continues to puzzle practitioners, yet diagnostic criteria and evidence based treatment is available. Methods The medical literature has been searched exhaustively to access all articles (English language) pertaining to leg pains in children which are ascribed to being 'growing pains'. Results The literature, whilst plentiful in quantity and spanning two centuries, is generally replete with reiterated opinion and anecdote and lacking in scientific rigour. The author searched 45 articles for relevance, determined according to title, abstract and full text, resulting in a yield of 22 original studies and 23 review articles. From the original studies, one small (non-blinded) randomised controlled trial that focused on GP treatment with leg muscle stretching was found. Nine prevalence studies were found revealing disparate estimates. Ten cohort (some case-controlled) studies, which investigated pain attribute differences in affected versus unaffected groups, were found. One series of single case experiment designs and one animal model study were found. Conclusion Growing pains is prevalent in young children, presents frequently in the health care setting where it is poorly managed and is continuing to be researched. A common childhood complaint, growing pains needs to be acknowledged and better managed in the contemporary medical setting. PMID:18822152

  7. Growing local likelihood network: Emergence of communities

    NASA Astrophysics Data System (ADS)

    Chen, S.; Small, M.

    2015-10-01

    In many real situations, networks grow only via local interactions. New nodes are added to the growing network with information only pertaining to a small subset of existing nodes. Multilevel marketing, social networks, and disease models can all be depicted as growing networks based on local (network path-length) distance information. In these examples, all nodes whose distance from a chosen center is less than d form a subgraph. Hence, we grow networks with information only from these subgraphs. Moreover, we use a likelihood-based method, where at each step we modify the networks by changing their likelihood to be closer to the expected degree distribution. Combining the local information and the likelihood method, we grow networks that exhibit novel features. We discover that the likelihood method, over certain parameter ranges, can generate networks with highly modulated communities, even when global information is not available. Communities and clusters are abundant in real-life networks, and the method proposed here provides a natural mechanism for the emergence of communities in scale-free networks. In addition, the algorithmic implementation of network growth via local information is substantially faster than global methods and allows for the exploration of much larger networks.

  8. Growing inhomogeneities in cosmological Goldstone modes

    NASA Astrophysics Data System (ADS)

    Benson, Katherine M.

    1992-08-01

    We examine the evolution of initial inhomogeneities in a Goldstone field in an expanding Friedmann-Robertson-Walker universe. We find subhorizon inhomogeneities grow, relative to the homogeneous state. This stems not from growing fluctuations - which simply redshift - but from rapid (ϱ ~ a-6) decay of the homogeneous state. We show how Goldstone modes escape assumptions - some inapplicable, some ill-founded - underpinning conventional analyses of cosmological fluctuations. Finally, we reconcile our analysis to standard cosmology, noting that the Goldstone evolution is essentially decoupled and dynamical. This material is based upon work supported by NSF grants PHY-87-14654 (while the author was at Harvard University) and PHY91-06210.

  9. Growing pioneer plants for a lunar base

    NASA Astrophysics Data System (ADS)

    Kozyrovska, N. O.; Lutvynenko, T. L.; Korniichuk, O. S.; Kovalchuk, M. V.; Voznyuk, T. M.; Kononuchenko, O.; Zaetz, I.; Rogutskyy, I. S.; Mytrokhyn, O. V.; Mashkovska, S. P.; Foing, B. H.; Kordyum, V. A.

    A precursory scenario of cultivating the first plants in a lunar greenhouse was elaborated in frames of a conceptual study to grow plants for a permanently manned lunar base. A prototype plant growth system represents an ornamental plant Tagetes patula L. for growing in a lunar rock anorthosite as a substrate. Microbial community anticipated to be in use to support a growth and development of the plant in a substrate of low bioavailability and provide an acceptable growth and blossoming of T. patula under growth limiting conditions.

  10. Feasibility of using plants to assist in the remediation of heavy metal contamination at J-Field, Aberdeen Proving Ground, Maryland. Final report

    SciTech Connect

    Jastrow, J.D.

    1995-11-03

    Most remedial technologies currently being used at hazardous waste sites (e.g., containment, excavation, soil washing, or incineration) are expensive. Further, in some locations technologies involving excavation could increase off-site releases of hazardous materials by destabilizing the site. Thus, interest in the development of in situ bioremediation technologies has grown substantially over the last decade. The idea of phytoremediation (i.e., using plants to clean up toxic wastes) is generating increasing attention from scientists, industry, and government agencies. The attractiveness of phytoremediation stems from its potential (1) to be less expensive than technologies involving the human engineering costs of soil manipulation, and (2) to initiate simultaneously both the clean up of hazardous materials and site restoration. The purpose of this project was to investigate the potential for using plants to remediate J-Field soils contaminated with heavy metals. Phragmites australis, one of the dominant species in the Toxic Burning Pits (TBP) area and other contaminated sites within J-Field, appears to be both tolerant of heavy metal contaminated soil conditions and capable of producing large amounts of biomass. Consequently, this project has concentrated on characterizing heavy metal accumulation by Phragmites australis growing in the TBP area relative to soil concentrations and availabilities. This type of information is necessary to determine the feasibility of using this species to assist in the remediation of metal contaminated soils at J-Field.

  11. Growing Great Minds: Seizing the Opportunity

    ERIC Educational Resources Information Center

    Grant, Carl A.

    2015-01-01

    Teachers must seize the opportunity to grow great minds. Contextualizing the argument in the writing of renowned poets, noted educators, and distinguished moral heroes whose life's work was dedicated to the principles of democracy, this article reminds practicing teachers in this challenging moment that "You are braver than you believe,…

  12. Growing Up Chicana/o: An Anthology.

    ERIC Educational Resources Information Center

    Lopez, Tiffany Ana

    This is a collection of 20 stories that focus specifically on the experience of growing up Chicana/o. A foreword by Rudolfo Anaya provides background on the development of Chicano literature. The stories are presented in four sections that explore the themes of heritage and actual and metaphorical boundaries, the importance of grandparents and…

  13. GRoW Buffalo Final Report

    SciTech Connect

    Bohm, Martha

    2016-04-17

    This document provides final reporting on the GRoW Home, University at Buffalo's entry to the 2015 Solar Decathlon competition in Irvine, CA. The report summarizes fundraising efforts, documents media outreach, lists online presence, analyzes the organizer's communication, describes post-competition life of the house and future employment plans for student team members. Last, it suggests improvements for future decathlons.

  14. Growing Up in Germany: A National Report.

    ERIC Educational Resources Information Center

    Krappmann, Lothar

    1999-01-01

    Summarizes a Federal Ministry of Youth report on the conditions under which children grow up in Germany. Notes manifold problems that children face under today's living conditions. Presents recommendations and suggestions for providing a network of measures, relationships, and institutions to support children's development and education in family,…

  15. The need for growing crystals in space

    NASA Technical Reports Server (NTRS)

    Kern, E. L.

    1981-01-01

    Payoffs of crystal growth in space in the areas of understanding growth and melt flow mechanisms, the growth of more uniform crystals with fewer defects, and the growth of crystals difficult or impossible to grow on Earth are summarized. The advantages of various heating methods are summarized. Critical devices requiring the uniformity and lower defect density of crystals grown in space are listed.

  16. Pressure Points in Growing Up Indian.

    ERIC Educational Resources Information Center

    Witt, Shirley Hill

    1980-01-01

    Describes the cultural contradictions between traditional American Indian child-rearing practices and "mainstream" Anglo expectations. Discusses the psychological consequences of growing up with such culture conflict, and condemns educational and social policies which ignore the American Indians' traditions and exacerbate their alienation. (GC)

  17. Pueblo Girls: Growing Up in Two Worlds.

    ERIC Educational Resources Information Center

    Keegan, Marcia

    This book portrays San Ildefonso Pueblo on the east bank of the Rio Grande river in New Mexico through the lives of Sonja, age 10, and her sister Desiree, age 8. Growing up in San Ildefonso Pueblo, the girls enjoy the same activities as other American girls, such as basketball, cheerleading, playing video games, and sending e-mail. But they also…

  18. Growing Income Inequality Threatens American Education

    ERIC Educational Resources Information Center

    Duncan, Greg J.; Murnane, Richard J.

    2014-01-01

    The first of two articles in consecutive months describes the origins and nature of growing income inequality, and some of its consequences for American children. It documents the increased family income inequality that's occurred over the past 40 years and shows that the increased income disparity has been more than matched by an expanding…

  19. Multidimensional neural growing networks and computer intelligence

    SciTech Connect

    Yashchenko, V.A.

    1995-03-01

    This paper examines information-computation processes in time and in space and some aspects of computer intelligence using multidimensional matrix neural growing networks. In particular, issues of object-oriented {open_quotes}thinking{close_quotes} of computers are considered.

  20. Growing up as a Young Artist

    ERIC Educational Resources Information Center

    Szekely, George

    2012-01-01

    "Growing Up as a Young Artist" is an illustrated book assignment that involves researching family scrapbooks, photo albums and films, and inquiring about family anecdotes for clues to one's artistic roots. Students creatively reflect on their early memories of imaginative events, as each page is filled with memories of creative activities they…

  1. Growing a Forest for the Trees.

    ERIC Educational Resources Information Center

    Growing Ideas, 2001

    2001-01-01

    Describes a tree studies program in a fourth-grade classroom. Students collected local tree seeds and seeds from supermarket fruits, researched growing conditions, and grew seeds under various conditions. Students kept journals on local trees, observing seed dispersal mechanisms and examining rings on trunk slices. Inquiry-based tree studies…

  2. Asymmetric Die Grows Purer Silicon Ribbon

    NASA Technical Reports Server (NTRS)

    Kalejs, J. P.; Chalmers, B.; Surek, T.

    1983-01-01

    Concentration of carbide impurities in silicon ribbon is reduced by growing crystalline ribbon with die one wall higher than other. Height difference controls shape of meniscus at liquid/crystal interface and concentrates silicon carbide impurity near one of broad faces. Opposite face is left with above-average purity. Significantly improves efficiency of solar cells made from ribbon.

  3. Time for Gas Planets to Grow

    NASA Technical Reports Server (NTRS)

    Lissauer, Jack J.; DeVincenzi, Donald (Technical Monitor)

    2001-01-01

    Giant planets like Jupiter need a large reservoir of gas to grow to full size. New observations indicate that such planetary nurseries last twice as long as previously thought. These observations, and their implications for the abundance of Jupiter-like planets within our galaxy, are discussed herein.

  4. Prealloyed catalyst for growing silicon carbide whiskers

    DOEpatents

    Shalek, Peter D.; Katz, Joel D.; Hurley, George F.

    1988-01-01

    A prealloyed metal catalyst is used to grow silicon carbide whiskers, especially in the .beta. form. Pretreating the metal particles to increase the weight percentages of carbon or silicon or both carbon and silicon allows whisker growth to begin immediately upon reaching growth temperature.

  5. Growing Greener Cities: Environmental Education Guide.

    ERIC Educational Resources Information Center

    American Forestry Association, Washington, DC.

    This environmental education guide, developed by American Forests, includes five lessons created to help teachers use "Growing Greener Cities," a tree-planting handbook. The lessons are designed to teach students the role trees and forests play in cities. Lesson one begins with an introduction, several preparatory exercises to orient students to…

  6. Growing a New Generation of Music Teachers

    ERIC Educational Resources Information Center

    Burrack, Frederick

    2009-01-01

    In many parts of the United States, there is a growing shortage of music teachers to take the place of the retiring teachers. This is most evident in rural areas. If music teachers are not available to fill openings, music positions are sometimes combined, spreading music teachers too thin and requiring them to possess multiple music…

  7. Growing and Sustaining Communities with Bioenergy

    SciTech Connect

    Havill, Alice; Schultz, Donny; Falcon, Nigel; Reetz, Harold; Rowden, Jack; Van Horn, Ruth; Nordling, Debbie; Naig, Mike

    2015-10-21

    From Vero Beach, Florida, to Hugoton, Kansas, to Emmetsburg, Iowa, cellulosic ethanol biorefineries have had major impacts on communities and their residents. In other areas, bioenergy has significant potential to transform current and establish new industry. This short video illustrates how biorefineries and other bioenergy developments can benefit citizens, businesses, and whole communities, helping America’s rural economies grow and thrive.

  8. A Little Salesmanship "Grows" a Long Way

    ERIC Educational Resources Information Center

    Montas, Leah

    2012-01-01

    Goshen Elementary PTA's membership shrank the first year the author was PTA president. In the back of her mind, she was bothered by the fact that their membership numbers had dropped. So, after she attended a regional session with her vice president on growing membership, she got the courage to propose something different. They discussed with…

  9. Teaching the Growing Population of Nontraditional Students.

    ERIC Educational Resources Information Center

    Wagner, June G.

    2002-01-01

    This document contains three articles on teaching the growing population of nontraditional students. "The Changing Demographics of the Classroom" defines "nontraditional students"; reviews the characteristics, risk factors, and special needs of nontraditional students; and identifies the following services as particularly important to…

  10. Postponed Parenthood: A Growing Canadian Family Pattern.

    ERIC Educational Resources Information Center

    Schlesinger, Benjamin; Schlesinger, Rachel

    Postponed parenthood is a growing family pattern in Canada. To examine this trend, an exploratory study of 46 couples who were delayed parents was conducted in Toronto. The members of each couple had worked at least 5 years prior to the birth of their first child after the mother was age 30. Responses by both husbands and wives to a questionnaire…

  11. Twenty Tips for Growing a Baby's Brain.

    ERIC Educational Resources Information Center

    Honig, Alice Sterling

    This paper asserts that the more enriching the interactions and experiences that parents and child caregivers provide to very young children, the more chances they are providing for growing neural connections and pathways in the brain to support language, reasoning, and planning skills; mental health and emotional well-being; and motor…

  12. Rotating Vessels for Growing Protein Crystals

    NASA Technical Reports Server (NTRS)

    Cottingham, Paul

    2005-01-01

    Rotating vessels have been proposed as means of growing larger, more nearly uniform protein crystals than would otherwise be possible in the presence of normal Earth gravitation. Heretofore, nonrotating vessels have been used. It is difficult to grow high-quality protein crystals in the terrestrial gravitational field because of convection plumes created by the interaction between gravitation and density gradients in protein-solution depletion layers around growing crystals. The density gradients and the associated convection plumes cause the surfaces of growing crystals to be exposed to nonuniform solution densities, thereby causing the crystals to form in irregular shapes. The microgravitational environment of outer space has been utilized to eliminate gravitation-induced convection, but this approach is generally not favorable because of the high cost and limited availability of space flight. The use of a rotating vessel according to the proposal is intended to ameliorate the effects of gravitation and the resultant convection, relative to the corresponding effects in a non-rotating vessel. The rotation would exert an averaging effect over time, distributing the convective force on the depletion layer. Therefore, the depletion layer would be more nearly uniform and, as a result, the growing crystal would be more nearly perfect. The proposal admits of variations (see figure), including the following: The growing crystal could be rotated about its own central axis or an external axis. The crystal-growth vessel could be of any of various shapes, including cylindrical, hemispherical, conical, and combinations thereof. The crystal-growth vessel could be suspended in a viscous fluid in an outer vessel to isolate the growing crystal from both ambient vibrations and vibrations induced by a mechanism that drives the rotation. The rotation could be coupled to the crystal-growth vessel by viscous or magnetic means. The crystal-growth vessel could be supported within the

  13. To Grow or Not to Grow: Questions about Economic Development. Small Town Strategy.

    ERIC Educational Resources Information Center

    Coppedge, Robert O.

    Part of the Small Town Strategy series, this publication is designed to help communities decide whether further local economic growth is possible and desirable. The publication provides a discussion outline to be used to study the costs and benefits of growing or not growing. Questions are listed which should be raised by the community when…

  14. Method for horizontally growing ribbon crystal

    NASA Technical Reports Server (NTRS)

    Kudo, B.

    1980-01-01

    A high speed method for forming ribbon crystal of desired width and thickness is characterized by drawing out the ribbon through a space whose distance is 5.7 times that of the thickness of the grown ribbon. The ribbon is drawn out between the molten body of the lower surface and the tip of the upper surface of the seed crystal and growing crystal. The ribbon growing at the tip of the seed crystal is drawn out horizontally and centrifugally by controlling the amount of cooling and heating. The temperature is maintained about equal to the upper surface of the outlets from which the molten substance is drawn, at least in certain portions of the crucible rim, the rim is elevated to prevent dropping of the molten raw material.

  15. Morphological instability of a thermophoretically growing deposit

    NASA Technical Reports Server (NTRS)

    Castillo, Jose L.; Garcia-Ybarra, Pedro L.; Rosner, Daniel E.

    1992-01-01

    The stability of the planar interface of a structureless solid growing from a depositing component dilute in a carrier fluid is studied when the main solute transport mechanism is thermal (Soret) diffusion. A linear stability analysis, carried out in the limit of low growth Peclet number, leads to a dispersion relation which shows that the planar front is unstable either when the thermal diffusion factor of the condensing component is positive and the latent heat release is small or when the thermal diffusion factor is negative and the solid grows over a thermally-insulating substrate. Furthermore, the influence of interfacial energy effects and constitutional supersaturation in the vicinity of the moving interface is analyzed in the limit of very small Schmidt numbers (small solute Fickian diffusion). The analysis is relevant to physical vapor deposition of very massive species on cold surfaces, as in recent experiments of organic solid film growth under microgravity conditions.

  16. Growing of sugar cane for energy

    SciTech Connect

    Humbert, R.P.

    1980-06-01

    The Brazilian alcohol program is reviewed and research into ways of increasing sugar cane yields discussed. Sugar cane varieties are being selected for their ''total sugars'' production. The effects of supplimentary applications of fertilizers and irrigations are being investigated. Time up to several months can be saved because in the growing of sugar cane for alcohol and cellulose it is not necessary to ripen the cane to convert most of the sugars to sucrose. The author feels that growing sugar cane for alcohol has a lot of potential for petroleum importing contries in the tropics. Smaller sugar mills, no longer economic for sugar production, can be economic for alcohol production as the energy requirements are far less.

  17. Impact of Growing Business on Software Processes

    NASA Astrophysics Data System (ADS)

    Nikitina, Natalja; Kajko-Mattsson, Mira

    When growing their businesses, software organizations should not only put effort into developing and executing their business strategies, but also into managing and improving their internal software development processes and aligning them with business growth strategies. It is only in this way they may confirm that their businesses grow in a healthy and sustainable way. In this paper, we map out one software company's business growth on the course of its historical events and identify its impact on the company's software production processes and capabilities. The impact concerns benefits, challenges, problems and lessons learned. The most important lesson learned is that although business growth has become a stimulus for starting thinking and improving software processes, the organization lacked guidelines aiding it in and aligning it to business growth. Finally, the paper generates research questions providing a platform for future research.

  18. Modeling wealth distribution in growing markets

    NASA Astrophysics Data System (ADS)

    Basu, Urna; Mohanty, P. K.

    2008-10-01

    We introduce an auto-regressive model which captures the growing nature of realistic markets. In our model agents do not trade with other agents, they interact indirectly only through a market. Change of their wealth depends, linearly on how much they invest, and stochastically on how much they gain from the noisy market. The average wealth of the market could be fixed or growing. We show that in a market where investment capacity of agents differ, average wealth of agents generically follow the Pareto-law. In few cases, the individual distribution of wealth of every agentcould also be obtained exactly. We also show that the underlying dynamics of other well studied kinetic models of markets can be mapped to the dynamics of our auto-regressive model.

  19. Growing American midwifery: the certified midwife credential.

    PubMed

    Farley, Cindy L; Tringali, Tanya; O'Connor, Sara

    2013-01-01

    Interest in the CM pathway to midwifery education is widely distributed across the US and not just tied to states in which the CM credential is legally recognized. The challenges to gain widespread legal recognition should not prevent us from losing sight of the potential for national growth in the midwifery workforce through advocacy for this credential. Midwifery leaders, practitioners and new graduates, CNMs, CMs and CPMs together, must work concurrently in education and health policy to bring about such change. Innovative solutions to expand midwifery that are firmly situated in the philosophical tenets and hallmarks of midwifery care are important to explore. Growing educational pathways leading to the CM credential is an example of an innovation that will strengthen and grow the American midwifery workforce, for the betterment of the women we serve.

  20. Anterior Cruciate Ligament Injuries in Growing Skeleton

    PubMed Central

    AlHarby, Saleh W.

    2010-01-01

    Anterior cruciate ligament (ACL) injuries in the adult patients are thoroughly studied and published in orthopedic literature. Until recently, little was known about similar injuries in skeletally growing patients. The more frequent involvement of this age group in various athletic activities and the improved diagnostic modalities have increased the awareness and interest of ACL injuries in skeletally immature patients. ACL reconstruction in growing skeleton is controversial and carries some risks to the tibial and femoral growth plate. A guarded approach to ACL reconstruction is recommended in skeletally immature patients. Modification of activity of ACL injured young patient, proper rehabilitation and prudent planning of adolescent age ACL reconstruction carries the least risks of growth plate violation. PMID:21475528

  1. Elastic Instability in Growing Yeast Colonies

    PubMed Central

    Nguyen, Baochi; Upadhyaya, Arpita; van Oudenaarden, Alexander; Brenner, Michael P.

    2004-01-01

    The differential adhesion between cells is believed to be the major driving force behind the formation of tissues. The idea is that an aggregate of cells minimizes the overall adhesive energy between cell surfaces. We demonstrate in a model experimental system that there exist conditions where a slowly growing tissue does not minimize this adhesive energy. A mathematical model demonstrates that the instability of a spherical shape is caused by the competition between elastic and surface energies. PMID:15111392

  2. Close-packing of growing discs

    SciTech Connect

    Bursill, L.A.; Xudong, F. . School of Physics)

    1988-12-01

    Spiral lattices are derived by allowing growing discs to aggregate under a close-packing rule. Both Fibonacci and Lucas numbers of visible spirals arise naturally, dependent only on the choice of growth centre. Both the rate of convergence towards an ideal spiral, and chirality, are determined by the initial placement of the first few discs (initial conditions). Thus the appearance of spiral packings is no more or less mysterious than the appearance of hexagonal packed arrays of equal discs.

  3. Growing and Sustaining Communities with Bioenergy

    ScienceCinema

    Havill, Alice; Schultz, Donny; Falcon, Nigel; Reetz, Harold; Rowden, Jack; Van Horn, Ruth; Nordling, Debbie; Naig, Mike

    2016-10-19

    From Vero Beach, Florida, to Hugoton, Kansas, to Emmetsburg, Iowa, cellulosic ethanol biorefineries have had major impacts on communities and their residents. In other areas, bioenergy has significant potential to transform current and establish new industry. This short video illustrates how biorefineries and other bioenergy developments can benefit citizens, businesses, and whole communities, helping America’s rural economies grow and thrive.

  4. Ferromanganese crusts and nodules, rocks that grow

    USGS Publications Warehouse

    Mizell, Kira; Hein, James

    2016-01-01

    Ferromanganese (Fe-Mn) crusts and nodules are marine sed- imentary mineral deposits, composed mostly of iron and manganese oxides. They precipitate very slowly from seawa- ter, or for nodules also from deep-sea sediment pore waters, recording the chemical signature of these source waters as they grow. Additional elements incorporate via sorption pro- cesses onto the Fe-Mn oxides, including rare and valuable metals that can reach concentrations that are economically valuable.

  5. Energy and protein utilization in growing cattle.

    PubMed

    Geay, Y

    1984-03-01

    Limited data are available to describe the different phases of dietary protein and energy utilization in growing cattle as compared with those in adult cattle or in growing nonruminants. The European data on this topic are summarized to indicate application in appropriate feeding standards. Net protein requirements are widely variable with breed and sex. They are lower in steers than in bulls and lower in early maturing than in late maturing breeds. They are clearly defined for growing and fattening bulls where they are influenced by breed, live weight and live weight gain. New systems have been proposed to express the protein allowances. They provide a great step towards a concept explaining N supply to ruminants. However, protein degradability in the rumen, efficiency of microbial protein synthesis, intestinal digestibility and metabolic efficiency of amino acid absorption in the intestine need to be described more accurately. Even if body energy retention measured by the slaughter technique is systematically lower than when measured by calorimetric balance, both techniques can correctly describe the effect of breed sex, weight, or daily gain on energy retained, in relative value, and its distribution between protein and fat deposition. But further research is needed to confirm the distribution of metabolizable energy between maintenance and growth and the efficiency of metabolizable energy utilization for growth. Thus, different authors have preferred to calculate the energy allowances, not by a factorial method, but by regression between energy intake and the corresponding weight and daily gain of animals measured during feeding trials.

  6. Region growing with pulse-coupled neural networks: an alternative to seeded region growing.

    PubMed

    Stewart, R D; Fermin, I; Opper, M

    2002-01-01

    The seeded region growing (SRG) algorithm is a fast robust parameter-free method for segmenting intensity images given initial seed locations for each region. The requirement of predetermined seeds means that the model cannot operate fully autonomously. In this paper, we demonstrate a novel region growing variant of the pulse-coupled neural network (PCNN), which offers comparable performance to the SRG and is able to generate seed locations internally, opening the way to fully autonomous operation.

  7. Growing media constituents determine the microbial nitrogen conversions in organic growing media for horticulture.

    PubMed

    Grunert, Oliver; Reheul, Dirk; Van Labeke, Marie-Christine; Perneel, Maaike; Hernandez-Sanabria, Emma; Vlaeminck, Siegfried E; Boon, Nico

    2016-05-01

    Vegetables and fruits are an important part of a healthy food diet, however, the eco-sustainability of the production of these can still be significantly improved. European farmers and consumers spend an estimated €15.5 billion per year on inorganic fertilizers and the production of N-fertilizers results in a high carbon footprint. We investigated if fertilizer type and medium constituents determine microbial nitrogen conversions in organic growing media and can be used as a next step towards a more sustainable horticulture. We demonstrated that growing media constituents showed differences in urea hydrolysis, ammonia and nitrite oxidation and in carbon dioxide respiration rate. Interestingly, mixing of the growing media constituents resulted in a stimulation of the function of the microorganisms. The use of organic fertilizer resulted in an increase in amoA gene copy number by factor 100 compared to inorganic fertilizers. Our results support our hypothesis that the activity of the functional microbial community with respect to nitrogen turnover in an organic growing medium can be improved by selecting and mixing the appropriate growing media components with each other. These findings contribute to the understanding of the functional microbial community in growing media and its potential role towards a more responsible horticulture.

  8. Sunset Specialty Turf: Growing the heap

    SciTech Connect

    Heumann, J.M.

    1998-07-01

    Almost a quarter of the municipal solid waste (MSW) generated in the US is compostable. As composting as an industry is growing in the US, entrepreneurs are going where the markets are to expand their facilities and, hopefully, their revenues by making turf and groundcovers from recovered materials. In fact, over the past 20 years, the composting business has grown from a nascent backyard project to a full-fledged industry in the US. According to the US EPA`s recent waste characterization report, food and yard waste generated in the US in 1996 came to almost 53 million tons, or almost a quarter of the total 209 million tons of MSW generated in the US. Of the 28 million tons of yard waste generated in the US in 1996 alone, 38.6% was recycled. Yard trimmings made up about 13.4% of all the materials discarded as MSW. With its warm climate and abundance of foliage that create yard waste year round, the South is a region where composting facilities are thriving. And a Midwestern composting company is looking to reap the benefits of the current growing market for compostable materials in the Southeast while providing an environmentally beneficial end product. Sunset Turf Nursery, Inc. is a company that manufacturers turf products from compost materials. The company already runs a 51-acre facility in St. Louis, where it composts municipal materials and, using its patented process, grows turf grass to make a specialty groundcover which can be used for landscaping applications. Sunset officials plan to expand the company`s composting and turf manufacturing operations to more than 350 acres over the next three years, starting with the St. Louis facility. The company, specifically its division Sunset Specialty Turf, currently has a research and development testing site in Jacksonville, Florida, which it would like to use additional funding to expand to a full fledged manufacturing site similar to the St. Louis site.

  9. Features and heterogeneities in growing network models

    NASA Astrophysics Data System (ADS)

    Ferretti, Luca; Cortelezzi, Michele; Yang, Bin; Marmorini, Giacomo; Bianconi, Ginestra

    2012-06-01

    Many complex networks from the World Wide Web to biological networks grow taking into account the heterogeneous features of the nodes. The feature of a node might be a discrete quantity such as a classification of a URL document such as personal page, thematic website, news, blog, search engine, social network, etc., or the classification of a gene in a functional module. Moreover the feature of a node can be a continuous variable such as the position of a node in the embedding space. In order to account for these properties, in this paper we provide a generalization of growing network models with preferential attachment that includes the effect of heterogeneous features of the nodes. The main effect of heterogeneity is the emergence of an “effective fitness” for each class of nodes, determining the rate at which nodes acquire new links. The degree distribution exhibits a multiscaling behavior analogous to the the fitness model. This property is robust with respect to variations in the model, as long as links are assigned through effective preferential attachment. Beyond the degree distribution, in this paper we give a full characterization of the other relevant properties of the model. We evaluate the clustering coefficient and show that it disappears for large network size, a property shared with the Barabási-Albert model. Negative degree correlations are also present in this class of models, along with nontrivial mixing patterns among features. We therefore conclude that both small clustering coefficients and disassortative mixing are outcomes of the preferential attachment mechanism in general growing networks.

  10. Growing Networks with Positive and Negative Links

    NASA Astrophysics Data System (ADS)

    Dech, Corynne; Antwi, Shadrack; Shaw, Leah

    Scale-free networks grown via preferential attachment have been used to model real-world networks such as the Internet, citation networks, and social networks. Here we investigate signed scale-free networks where an edge represents a positive or negative connection. We present analytic results and simulation for a growing signed network model. We compare the signed network to an unsigned scale-free network. We discuss several options for preferential attachment in a signed network that could be further adapted to model the accumulation of links over time in real-world signed networks.

  11. Parallelized seeded region growing using CUDA.

    PubMed

    Park, Seongjin; Lee, Jeongjin; Lee, Hyunna; Shin, Juneseuk; Seo, Jinwook; Lee, Kyoung Ho; Shin, Yeong-Gil; Kim, Bohyoung

    2014-01-01

    This paper presents a novel method for parallelizing the seeded region growing (SRG) algorithm using Compute Unified Device Architecture (CUDA) technology, with intention to overcome the theoretical weakness of SRG algorithm of its computation time being directly proportional to the size of a segmented region. The segmentation performance of the proposed CUDA-based SRG is compared with SRG implementations on single-core CPUs, quad-core CPUs, and shader language programming, using synthetic datasets and 20 body CT scans. Based on the experimental results, the CUDA-based SRG outperforms the other three implementations, advocating that it can substantially assist the segmentation during massive CT screening tests.

  12. Cultural systems for growing potatoes in space

    NASA Technical Reports Server (NTRS)

    Tibbitts, T.; Bula, R.; Corey, R.; Morrow, R.

    1988-01-01

    Higher plants are being evaluated for life support to provide needed food, oxygen and water as well as removal of carbon dioxide from the atmosphere. The successful utilization of plants in space will require the development of not only highly productive growing systems but also highly efficient bioregenerative systems. It will be necessary to recycle all inedible plant parts and all human wastes so that the entire complement of elemental compounds can be reused. Potatoes have been proposed as one of the desirable crops because they are 1) extremely productive, yielding more than 100 metric tons per hectare from field plantings, 2) the edible tubers are high in digestible starch (70%) and protein (10%) on a dry weight basis, 3) up to 80% of the total plant production is in tubers and thus edible, 4) the plants are easily propagated either from tubers or from tissue culture plantlets, 5) the tubers can be utilized with a minimum of processing, and 6) potatoes can be prepared in a variety of different forms for the human diet (Tibbitts et al., 1982). However potatoes have a growth pattern that complicates the development of growing the plants in controlled systems. Tubers are borne on underground stems that are botanically termed 'rhizomes', but in common usage termed 'stolons'. The stolons must be maintained in a dark, moist area with sufficient provision for enlargement of tubers. Stems rapidly terminate in flowers forcing extensive branching and spreading of plants so that individual plants will cover 0.2 m2 or more area. Thus the growing system must be developed to provide an area that is darkened for tuber and root growth and of sufficient size for plant spread. A system developed for growing potatoes, or any plants, in space will have certain requirements that must be met to make them a useful part of a life support system. The system must 1) be constructed of materials, and involve media, that can be reused for many successive cycles of plant growth, 2

  13. Cultural systems for growing potatoes in space.

    PubMed

    Tibbitts, T; Bula, R; Corey, R; Morrow, R

    1988-01-01

    Higher plants are being evaluated for life support to provide needed food, oxygen and water as well as removal of carbon dioxide from the atmosphere. The successful utilization of plants in space will require the development of not only highly productive growing systems but also highly efficient bioregenerative systems. It will be necessary to recycle all inedible plant parts and all human wastes so that the entire complement of elemental compounds can be reused. Potatoes have been proposed as one of the desirable crops because they are 1) extremely productive, yielding more than 100 metric tons per hectare from field plantings, 2) the edible tubers are high in digestible starch (70%) and protein (10%) on a dry weight basis, 3) up to 80% of the total plant production is in tubers and thus edible, 4) the plants are easily propagated either from tubers or from tissue culture plantlets, 5) the tubers can be utilized with a minimum of processing, and 6) potatoes can be prepared in a variety of different forms for the human diet (Tibbitts et al., 1982). However potatoes have a growth pattern that complicates the development of growing the plants in controlled systems. Tubers are borne on underground stems that are botanically termed 'rhizomes', but in common usage termed 'stolons'. The stolons must be maintained in a dark, moist area with sufficient provision for enlargement of tubers. Stems rapidly terminate in flowers forcing extensive branching and spreading of plants so that individual plants will cover 0.2 m2 or more area. Thus the growing system must be developed to provide an area that is darkened for tuber and root growth and of sufficient size for plant spread. A system developed for growing potatoes, or any plants, in space will have certain requirements that must be met to make them a useful part of a life support system. The system must 1) be constructed of materials, and involve media, that can be reused for many successive cycles of plant growth, 2

  14. Mapping Nutrients Crucial to a Growing Population

    NASA Astrophysics Data System (ADS)

    Tarnowski, J. R.; Cassidy, E. S.; Gerber, J. S.

    2011-12-01

    Over two billion people worldwide suffer from inadequate levels of micronutrients, mainly in the form of iodine, iron, and vitamin A deficiencies. With a growing population, producing crops that contain high amounts of these micronutrients is of increased importance. Addressing these deficiencies sustainably requires a detailed examination of the agricultural production of the micronutrients. The purpose of this study is to determine whether or not enough of these important nutrients are produced to meet the nutritional needs of the global population, and to determine where nutrients are most deficient. We used area specific crop production data to map where and how much iron and vitamin A are produced from major crops.

  15. Buoyancy effects of a growing, isolated dendrite

    NASA Technical Reports Server (NTRS)

    Canright, D.; Davis, S. H.

    1991-01-01

    The buoyancy effect of a growing isolated dendrite on the solidification process in the undercooling liquid material was investigated by developing an analytic solution to the growth/convection problem in powers of a buoyancy parameter G. The solution depends on the Prandtl number P and the Stefan number S (undercooling) for the local velocity and thermal fields and also the buoyant alteration of the interface shape. Results suggest that buoyancy effect for metals (low P) may be qualitatively different from that for organics (high P).

  16. Methane efflux from littoral vegetation stands of southern boreal lakes: An upscaled regional estimate

    NASA Astrophysics Data System (ADS)

    Bergström, Irina; Mäkelä, Suvi; Kankaala, Paula; Kortelainen, Pirkko

    We studied the role of vegetated littoral area in the efflux of methane (CH 4) in a southern boreal landscape (1600 km 2), in Finland, covered by 619 lakes. A regression model was constructed to describe the relationship between lake area or lake shoreline length and total macrophyte or total emergent macrophyte coverage. Phragmites australis and Equisetum fluviatile were by far the most widely distributed emergent macrophytes in the area with a proportion of 40% of all zone-forming macrophytes. The zone-forming floating-leaved species Nuphar lutea, Potamogeton natans and Sparganium spp. covered 44% of all vegetated littoral areas. The strong temperature dependence of the emission rates was taken into consideration in the emission estimations for P. australis and E. fluviatile. The regional efflux, estimated for the growing seasons 1998-2002, varied between 0.8×10 5 and 1.1×10 5 kg CH 4 and between 1.6×10 5 and 2.4×10 5 kg CH 4, respectively. The emissions from the stands of floating-leaved species were negligible compared to the emissions from stands of P. australis and E. fluviatile. This indicates that species specific emission rates and areal coverage of the dominating species, as well as ambient temperature, should all be carefully considered when estimating the total regional emissions of CH 4 from lake littorals. The natural open ombrogenous bogs and minerogenous fens in the study region covered a 2.5-fold larger area than P. australis and E. fluviatile littoral, but their emissions were estimated to be only 78% of the emissions of P. australis and E. fluviatile, indicating that vegetated lake littoral is an important natural CH 4 source in the region.

  17. Plasticity in food assimilation, retention time and coprophagy allow herbivorous cavies (Microcavia australis) to cope with low food quality in the Monte desert.

    PubMed

    Sassi, Paola L; Caviedes-Vidal, Enrique; Anton, Rosa; Bozinovic, Francisco

    2010-03-01

    Energy balance depends on the efficiency with which organisms make use of their trophic resources, and has direct impact on their fitness. There are environmental variations that affect the availability as well as the quality of such resources; energy extraction also depends on the design of the digestive tract. It is expected that features associated with food utilization will be subjected to selective pressures and show some adjustment to the variability of the environment. Since energetic constraints challenge animals to display digestive compensatory mechanisms, the objective of this study is to determine the physiological and behavioral responses to spatial and seasonal heterogeneity in food quality. We investigated digestive strategies (digestive efficiency and coprophagy) in cavies inhabiting two different populations, and hence naturally experiencing different levels of diet quality. Cavies under experimentally different quality diets showed changes in dry matter digestibility and intake, digesta retention time and coprophagy. Our results partially support the expectations from theory and also reveal interpopulation differences in the ability to cope with changes in food quality, and may explain the capability of Microcavia australis to colonize extreme habitats.

  18. Inhibition of human Kv3.1 current expressed in Xenopus oocytes by the toxic venom fraction of Androctonus australis hector.

    PubMed

    Cheikh, Amani; Benkhalifa, Rym; Landoulsi, Zied; Chatti, Imen; Ayeb, Mohamed El

    2014-11-01

    AahG50, the toxic fraction of Androctonus australis hector venom, was studied on human Kv3.1 channels activation, stably expressed in Xenopus oocytes using the two-electrode voltage clamp technique. AahG50 reduced Kv3.1 currents in a reversible concentration-dependent manner, with an IC50 value and a Hill coefficient of 40.4 ± 0.2 μg/ml and 1.3 ± 0.05, respectively. AahG50 inhibited IKv3.1 without modifying the current activation kinetics. The AahG50-induced inhibition of Kv3.1 channels was voltage-dependent, with a gradual increase at lower concentrations and over the voltage range of channels opening. However, at higher concentrations, the inhibition exhibited voltage dependence only in the first range of channels opening from -20 to +10 mV, but demonstrates a low degree of voltage-dependence when channels are fully activated. In the literature, toxins have previously been isolated from AahG50, KAaH1 and KAaH2 and were reported not to have any effect on IKv3.1. The present article's findings suggest that AahG50 may contain a peptidic component active on Kv3.1 channels, which inhibits IKv3.1 in a selective manner.

  19. Hematology, Serum Chemistry, and Early Hematologic Changes in Free-Ranging South American Fur Seals ( Arctocephalus australis ) at Guafo Island, Chilean Patagonia.

    PubMed

    Seguel, Mauricio; Muñoz, Francisco; Keenan, Alessandra; Perez-Venegas, Diego J; DeRango, Eugene; Paves, Hector; Gottdenker, Nicole; Müller, Ananda

    2016-07-01

    The establishment of clinical pathology baseline data is critical to evaluate temporal and spatial changes in marine mammal groups. Despite increased availability of studies on hematology and biochemistry of marine mammals, reference ranges are lacking for many populations, especially among fur seal species. During the austral summers of 2014 and 2015, we evaluated basic hematologic and biochemical parameters in clinically healthy, physically restrained South American fur seal ( Arctocephalus australis ) lactating females and 2-mo-old pups. We also assessed the temporal variation of hematology parameters on the pups during their first 2 mo of life. Reference ranges of lactating females were similar to those previously reported in other fur seal species. In the case of pups, reference ranges are similar to values previously reported in sea lion species. As expected, most biochemical and hematologic values differ significantly between adult females and pups. As in other otariids, South American fur seals pups are born with higher values of total red blood cells, hemoglobin, and packed cell volume, and lower numbers of total leukocytes, neutrophils, lymphocytes, and eosinophils. To the best of our knowledge, data on hematology reference values for South American fur seals has not been previously reported and is useful for continued health monitoring of this species, as well as for comparisons with other otariid groups.

  20. Comparison of swimming capacity and energetics of migratory European eel (Anguilla anguilla) and New Zealand short-finned eel (A. australis)

    PubMed Central

    Tudorache, Christian; Burgerhout, Erik; Brittijn, Sebastiaan; van den Thillart, Guido

    2015-01-01

    The spawning migration of the European eel (Anguilla anguilla) can cover more than 6000 km, while that of the New Zealand short-finned eel (A. australis) is assumed to be approximately 3000 km. Since these species are expected to show adaptive traits to such an important lifetime event, we hypothesized differences in swimming capacity and energetics as a response to this adaptation. In an experimental swimming respirometer set-up, critical swimming speed (Ucrit), optimal swimming speed (Uopt), mass specific oxygen consumption rate (ṀO2), standard metabolic rate (SMR), active metabolic rate at Ucrit (AMRcrit) and at Uopt (AMRopt), the minimum cost of transport at Uopt (COTmin), and the scope for activity, were assessed and compared between the species. With a similar body length and mass, European eels showed ca. 25% higher values for both Ucrit and Uopt, and 23% lower values for COTmin, compared to New Zealand short-finned eels. However, SMR, AMRcrit, AMRopt, and scope for activity did not differ between the species, indicating very similar swimming physiology traits. This study discusses physiological aspects of long distance migration and provides recommendations for (a) swimming respirometry in anguilliform fish, and (b) telemetry research using externally attached pop-up tags. PMID:26441675

  1. Death of a South American fur seal (Arctocephalus australis) after the ingestion of toads--evaluation of toad poisoning by toxicological analysis.

    PubMed

    Toennes, Stefan W; Peters, Martin; Osmann, Christine; Pogoda, Werner; Mebs, Dietrich

    2015-01-01

    Animals in zoological gardens are at risk of severe and even lethal poisoning when they accidentally ingest toads. Here we report the case of an eleven month old male South American fur seal (Arctocephalus australis) which was found dead in its outdoor enclosure in the zoo of Dortmund, Germany. Autopsy revealed the presence of two adult, partly digested common toads (Bufo bufo) in the stomach. Toxicological analysis of the stomach content using high performance liquid chromatography coupled to time-of-flight mass spectrometry (LC-TOF MS) proved the presence of bufadienolides, the major cardiotoxic components of toad poisons. Using electrochemical luminescens immunoassay (ECLIA) compounds equivalent to digitoxin were detected in the blood sample confirming the absorption of toad poison components from the intestines into the circulation potentially leading to cardiac failure. In zoological gardens special precautions are necessary to protect non-native animals from encountering toads and the risk of poisoning, particularly in early spring, the spawning period of the toads.

  2. Characteristics and Feasibility of Trans-Free Plastic Fats through Lipozyme TL IM-Catalyzed Interesterification of Palm Stearin and Akebia trifoliata Variety Australis Seed Oil.

    PubMed

    Zhao, Shi-Qiang; Hu, Jiang-Ning; Zhu, Xue-Mei; Bai, Chun-Qing; Peng, Hai-Long; Xiong, Hua; Hu, Ju-Wu; Zhao, Qiang

    2014-03-31

    Akebia trifoliata var. australis seed oil (ASO) was used as an edible oil in China. However, in-depth research studies on ASO have yet to be conducted for production of plastic fats in food industry. In this work, an immobilized lipase from Thermomyces lanuginosus (TL IM) was employed to catalyze palm stearin (PS) with different ratios of ASO in a laboratory-scale operation at 60 °C. The physical properties [e.g., fatty acid profile, slip melting point (SMP), solid fat content (SFC), polymorphic form, and microstructure] of physical blends (PBs) were analyzed and compared with those of the interesterified products (IPs). Results showed that SMPs of IPs (33.20-37.60 °C) decreased compared with those of PBs (48.03-49.30 °C). Meanwhile, IPs showed a good SFC range from 16.11% to 28.29% at 25 °C with mostly β' polymorphic forms determined by X-ray diffraction analysis. It should be mentioned that no trans fatty acids (TFAs) were detected in any products, suggesting much more health-benefits of IPs. Texture tests showed that PBs (3318.19 ± 86.67 g) were markedly harder than IPs (557.02 ± 12.75 g). Conclusively, our study demonstrated that ASO can be utilized to produce trans-free plastic fats with good qualities through lipase-catalyzed interesterification.

  3. Growing old: a psychoanalyst's point of view.

    PubMed

    Quinodoz, Danielle

    2009-08-01

    With the help of clinical examples, the author shows that psychoanalysis or psychotherapy after the age of 70 can be a fascinating experience, one that enables patients to reconstruct their internal history in such a way that their final years can be given their rightful place in the overall journey through life. Often it will be a matter of going beyond the conflict between paralysing time with the illusion of keeping death at bay and taking the transient nature of life into account in order to perceive its true flavour. We can grow old passively, juxtaposing different periods of our life without linking them together, thereby creating the illusion of time without end; or we can grow old actively, integrating the different phases of our life into a coherent historical narrative. This representation of time leaves the door open for experiences which the author calls 'small seconds of eternity'. We can all experience such moments when we are deeply moved - joyfully or painfully - by something, so that we perceive another quality of time that goes beyond its chronological dimension without all the same negating it. Helping elderly people to identify these seconds of eternity and catch hold of them can be an invaluable experience for them. Perhaps we need to see our life unfold through the chronology of its different phases in order to discover, second by second, how to express on an everyday basis something of which we have had an inkling in some second of eternity.

  4. Optimum folding pathways for growing protein chains.

    PubMed

    Senturk, Serife; Baday, Sefer; Arkun, Yaman; Erman, Burak

    2007-11-26

    The folding of a protein is studied as it grows residue by residue from the N-terminus and enters an environment that stabilizes the folded state. This mode of folding of a growing chain is different from refolding where the full chain folds from a disordered initial configuration to the native state. We propose a sequential dynamic optimization method that computes the evolution of optimum folding pathways as amino acid residues are added to the peptide chain one by one. The dynamic optimization formulation is deterministic and uses Newton's equations of motion and a Go-type potential that establishes the native contacts and excluded volume effects. The method predicts the optimal energy-minimizing path among all the alternative feasible pathways. As two examples, the folding of the chicken villin headpiece, a 36-residue protein, and chymotrypsin inhibitor 2 (CI2), a 64-residue protein, are studied. Results on the villin headpiece show significant differences from the refolding of the same chain studied previously. Results on CI2 mostly agree with the results of refolding experiments and computational work.

  5. Integral momentum balance on a growing bubble

    NASA Astrophysics Data System (ADS)

    Siedel, S.; Cioulachtjian, S.; Robinson, A. J.; Bonjour, J.

    2013-12-01

    The integral momentum balance on a growing boiling bubble is investigated. All forces acting on the bubble are detailed, and the methods and assumptions used to calculate their integral resultants are discussed. The momentum balance computation is then performed using experimental data of bubbles growing on an artificial nucleation site in a controlled environment. The relative magnitude of each force component is compared, showing negligible dynamic forces, upwards forces composed mainly of the buoyancy and contact pressure components, and downwards forces being exclusively due to surface tension and adhesion. The difficulty encountered in measuring the apparent contact angle due to mirage effects has been highlighted; a new method, fitting numerically simulated bubble profile to the contour measurements has been proposed and used to correct the effects of refraction on the bubble profile determination. As all forces acting on the bubble were measured, it was possible to estimate the residuals of the momentum balance. Their small value validated both the expressions used for the forces and the methodology to evaluate their value.

  6. Growing vascularized heart tissue from stem cells.

    PubMed

    Lim, Shiang Y; Hernández, Damián; Dusting, Gregory J

    2013-08-01

    The promise of stem cells to repair the heart after damage or heart attack has not been realized because most such cells are lost after transplantation. A new approach is to grow substantial viable pieces of cardiac tissue from human stem cells by cardiac tissue engineering. Such constructs must be fully vascularized and perfused to ensure the viability of clinically relevant volumes of tissue. This requires careful choice of cells, culture conditions, a biomaterial to act as scaffold, and crucial strategies for vascularization. Autologous stem cells with high plasticity, which would avoid the need for antirejection therapies after transplantation, are an attractive source of both cardiomyocytes and vascular cells. Most stem cells also have inherent paracrine activity, releasing cytoprotective factors and growth-promoting cytokines that can further stimulate tissue regeneration and neovascularization through recruitment of endogenous stem and progenitor cells. Current advances for growing vascularized and functional cardiac constructs with human stem cells are described, bringing us a step closer to the engineering of complex cardiac tissues such as pacemaker, conducting tissue, or contractile myocardial flaps ideal for transplantation. From studies in rats successful transplantation of thin constructs to the ventricle has been reported, but there remain further issues to resolve before larger human constructs will be available to test in the clinic.

  7. Morphoelastic rods Part II: Growing birods

    NASA Astrophysics Data System (ADS)

    Lessinnes, Thomas; Moulton, Derek E.; Goriely, Alain

    2017-03-01

    The general problem of determining the shape and response of two attached growing elastic Kirchhoff rods is considered. A description of the kinematics of the individual interacting rods is introduced. Each rod has a given intrinsic shape and constitutive laws, and a map associating points on the two rods is defined. The resulting filamentary structure, a growing birod, can be seen as a new filamentary structure. This kinematic description is used to derive the general equilibrium equations for the shape of the rods under loads, or equivalently, for the new birod. It is shown that, in general, the birod is not simply a Kirchhoff rod but rather, due to the internal constraints, new effects can appear. The two-dimensional restriction is then considered explicitly and the limit for small deformation is shown to be equivalent to the classic Timsohenko bi-metallic strip problem. A number of examples and applications are presented. In particular, the problem of two attached rods with intrinsic helical shape and uniform growth is computed in detail and a host of new interesting solutions and bifurcations are observed.

  8. Growing degree hours - a simple, accurate, and precise protocol to approximate growing heat summation for grapevines

    NASA Astrophysics Data System (ADS)

    Gu, S.

    2016-08-01

    Despite its low accuracy and consistency, growing degree days (GDD) has been widely used to approximate growing heat summation (GHS) for regional classification and phenological prediction. GDD is usually calculated from the mean of daily minimum and maximum temperatures (GDDmm) above a growing base temperature ( T gb). To determine approximation errors and accuracy, daily and cumulative GDDmm was compared to GDD based on daily average temperature (GDDavg), growing degree hours (GDH) based on hourly temperatures, and growing degree minutes (GDM) based on minute-by-minute temperatures. Finite error, due to the difference between measured and true temperatures above T gb is large in GDDmm but is negligible in GDDavg, GDH, and GDM, depending only upon the number of measured temperatures used for daily approximation. Hidden negative error, due to the temperatures below T gb when being averaged for approximation intervals larger than measuring interval, is large in GDDmm and GDDavg but is negligible in GDH and GDM. Both GDH and GDM improve GHS approximation accuracy over GDDmm or GDDavg by summation of multiple integration rectangles to reduce both finite and hidden negative errors. GDH is proposed as the standardized GHS approximation protocol, providing adequate accuracy and high precision independent upon T gb while requiring simple data recording and processing.

  9. NASA's Growing Commitment: The Space Garden

    NASA Technical Reports Server (NTRS)

    2005-01-01

    Astronauts cannot live on dehydrated ice cream alone. Like everyone else, they need their vegetables. Enter VEGGIE, the Deployable Vegetable System, currently under development by Orbital Technologies Corporation (ORBITEC). VEGGIE is the latest in a long line of vegetable production units ORBITEC is currently working on, with NASA assistance, to grow salad crops to supplement prepackaged foods during long stays in space. The primary goal of the VEGGIE project is to provide flight crews with palatable, nutritious, and safe sources of fresh food with minimal volume and operational resources. In addition, ORBITEC recognizes the age-old adage that gardening is good for the soul, and it acknowledges that gardens are beneficial for relaxation and recreation. As evidence, astronauts on the International Space Station (ISS), who often stay for periods of 6 months, have been enjoying plant experiments, which provide them with much missed greenery and can occupy valuable free time with an enjoyable task. VEGGIE is a project that grew out of technology developed by ORBITEC for the Biomass Production System (BPS). The BPS is equivalent in size to a Space Shuttle middeck locker, and provides four plant growth chambers. Each chamber has independent control of temperature, humidity, nutrient and water delivery, lighting, and atmospheric composition. The BPS flew to the ISS in 2002, and astronaut Dan Bursch had positive comments about his interaction with the plants while in orbit. Astronaut Peggy Whitson had similarly positive remarks during the following expedition while she was growing soybeans for another experiment. Whitson reflects on her time in space with the plantings on Expedition 5, "Although it doesn t sound like much, it was really exciting to see something green. I assumed that this was just because I really enjoy plants, but it surprised me that both of my crewmates were just as excited. They wanted photos of themselves with the plants and asked if they could eat

  10. The growing significance of hot intelligences.

    PubMed

    Mayer, John D; Caruso, David R; Panter, A T; Salovey, Peter

    2012-09-01

    Comments on the original article, "Intelligence: New findings and theoretical developments," by R. E. Nisbett, J. Aronson, C. Blair, W. Dickens, J. Flynn, D. F. Halpern, and E. Turkheimer (see record 2011-30298-001). The present authors note that Nisbett et al's review focuses on intelligences that have been topics of research through the 20th century. Since then, however, attention to a new group of intelligences that the present authors refer to as "hot intelligences" has been growing (Mayer, Salovey, & Caruso, 2004). Although Nisbett et al (2012) mentioned potential newcomers to the group of intelligences, such as practical intelligence, the present authors feel that future reviews should consider the burgeoning research in new conceptions of intelligence. Here the a