Science.gov

Sample records for aquatic plant morphotypes

  1. Aquatic Plant Control Research Program. Allelopathic Aquatic Plants for Aquatic Plant Management: A Feasibility Study

    DTIC Science & Technology

    1989-10-01

    block number) FIELD GROUP SUB-GROUP Allelopathy "Bioassay . Growth inhibition. Aquatic macrophytes. Biocontrol Lena minor 19. ABSTRACT (Continue on...Bibliography of Aquatic Plant Allelopathy ........ Al 2 ALLELOPATHIC AQUATIC PLANTS FOR AQUATIC PLANT MANAGEMENT; A FEASIBILITY STUDY Introduction Background 1...nutrients, water, and other biotic effects could have overriding effects that appear as competition or allelopathy . These biotic factors must be

  2. Aquatic Plants and their Control.

    ERIC Educational Resources Information Center

    Michigan State Dept. of Natural Resources, Lansing.

    Aquatic plants can be divided into two types: algae and macrophytes. The goal of aquatic plant management is to maintain a proper balance of plants within a lake and still retain the lake's recreational and economic importance. Aquatic plant management programs have two phases: long-term management (nutrient control), and short-term management…

  3. Aquatic Plants and their Control.

    ERIC Educational Resources Information Center

    Michigan State Dept. of Natural Resources, Lansing.

    Aquatic plants can be divided into two types: algae and macrophytes. The goal of aquatic plant management is to maintain a proper balance of plants within a lake and still retain the lake's recreational and economic importance. Aquatic plant management programs have two phases: long-term management (nutrient control), and short-term management…

  4. Protection Goals for Aquatic Plants

    EPA Science Inventory

    Someone once said plants are the ugly stepchildren of the toxicological world. This was not out of lack of respect for plants, but rather reflected the common assumption that aquatic plants were less sensitive than aquatic fauna to chemicals. We now know this is not a valid gener...

  5. Protection Goals for Aquatic Plants

    EPA Science Inventory

    Someone once said plants are the ugly stepchildren of the toxicological world. This was not out of lack of respect for plants, but rather reflected the common assumption that aquatic plants were less sensitive than aquatic fauna to chemicals. We now know this is not a valid gener...

  6. Introduced aquatic plants and algae

    USDA-ARS?s Scientific Manuscript database

    Non-native aquatic plants such as waterhyacinth and hydrilla severely impair the uses of aquatic resources including recreational faculties (lakes, reservoirs, rivers) as well as timely delivery of irrigation water for agriculture. Costs associated with impacts and management of all types of aquatic...

  7. Remote Sensing of Aquatic Plants.

    DTIC Science & Technology

    1979-10-01

    remote sensing methods for identification and assessment of expanses of aquatic plants. Both materials and techniques are examined for cost effectiveness and capability to sense aquatic plants on both the local and regional scales. Computer simulation of photographic responses was employed; Landsat, high-altitude photography, side-looking airborne radar, and low-altitude photography were examined to determine the capabilities of each for identifying and assessing aquatic plants. Results of the study revealed Landsat to be the most cost effective for regional surveys,

  8. Aquatic Plants Aid Sewage Filter

    NASA Technical Reports Server (NTRS)

    Wolverton, B. C.

    1985-01-01

    Method of wastewater treatment combines micro-organisms and aquatic plant roots in filter bed. Treatment occurs as liquid flows up through system. Micro-organisms, attached themselves to rocky base material of filter, act in several steps to decompose organic matter in wastewater. Vascular aquatic plants (typically, reeds, rushes, cattails, or water hyacinths) absorb nitrogen, phosphorus, other nutrients, and heavy metals from water through finely divided roots.

  9. Beaver herbivory on aquatic plants.

    PubMed

    Parker, John D; Caudill, Christopher C; Hay, Mark E

    2007-04-01

    Herbivores have strong impacts on marine and terrestrial plant communities, but their impact is less well studied in benthic freshwater systems. For example, North American beavers (Castor canadensis) eat both woody and non-woody plants and focus almost exclusively on the latter in summer months, yet their impacts on non-woody plants are generally attributed to ecosystem engineering rather than herbivory. Here, we excluded beavers from areas of two beaver wetlands for over 2 years and demonstrated that beaver herbivory reduced aquatic plant biomass by 60%, plant litter by 75%, and dramatically shifted plant species composition. The perennial forb lizard's tail (Saururus cernuus) comprised less than 5% of plant biomass in areas open to beaver grazing but greater than 50% of plant biomass in beaver exclusions. This shift was likely due to direct herbivory, as beavers preferentially consumed lizard's tail over other plants in a field feeding assay. Beaver herbivory also reduced the abundance of the invasive aquatic plant Myriophyllum aquaticum by nearly 90%, consistent with recent evidence that native generalist herbivores provide biotic resistance against exotic plant invasions. Beaver herbivory also had indirect effects on plant interactions in this community. The palatable plant lizard's tail was 3 times more frequent and 10 times more abundant inside woolgrass (Scirpus cyperinus) tussocks than in spatially paired locations lacking tussocks. When the protective foliage of the woolgrass was removed without exclusion cages, beavers consumed nearly half of the lizard's tail leaves within 2 weeks. In contrast, leaf abundance increased by 73-93% in the treatments retaining woolgrass or protected by a cage. Thus, woolgrass tussocks were as effective as cages at excluding beaver foraging and provided lizard's tail plants an associational refuge from beaver herbivory. These results suggest that beaver herbivory has strong direct and indirect impacts on populations and

  10. Aquatic plant control research

    SciTech Connect

    Pryfogle, P.A.; Rinehart, B.N.; Ghio, E.G.

    1997-05-01

    The Northwest region of the United States contains extensive canal systems that transport water for hydropower generation. Nuisance plants, including algae, that grow in these systems reduce their hydraulic capacity through water displacement and increased surface friction. Most control methods are applied in an ad hoc fashion. The goal of this work is to develop cost-effective, environmentally sound, long-term management strategies to prevent and control nuisance algal growth. This paper reports on a multi-year study, performed in collaboration with the Pacific Gas & Electric Company, to investigate algal growth in their canal systems, and to evaluate various control methodologies. Three types of controls, including mechanical, biological and chemical treatment, were selected for testing and evaluation. As part of this study, water quality data were collected and algal communities were sampled from numerous stations throughout the distribution system at regular intervals. This study resulted in a more comprehensive understanding of conditions leading to the development of nuisance algal growth, a better informed selection of treatment plans, and improved evaluation of the effectiveness for the control strategies selected for testing.

  11. Aquatic plants for removal of mevinphos from the aquatic environment

    NASA Technical Reports Server (NTRS)

    Wolverton, B. C.

    1975-01-01

    Fragrant waterlily (Nymphaea odorata, Ait.), joint-grass (Paspalum distichum L.), and rush (Juncus repens, Michx.) were used to evaluate the effectiveness of vascular aquatic plants in removing the insecticide mevinphos (dimethyl-1-carbomethoxy-1propen-2-yl phosphate) from waters contaminated with this chemical. The emersed aquatic plants fragrant waterlily and joint-grass removed 87 and 93 ppm of mevinphos from water test systems in less than 2 weeks without apparent damage to the plants; whereas rush, a submersed plant, removed less insecticide than the water-soil controls. Water-soil control still contained toxic levels of this insecticide, as demonstrated by fish bioassay studies, after 35 days.

  12. Control of Fish and Aquatic Plants.

    ERIC Educational Resources Information Center

    Hesser, R. B.; And Others

    This agriculture extension service publication from Pennsylvania State University is a handbook for the water body manager. The bulk of the contents deals with aquatic plant control. The different types of aquatic plants, their reproduction and growth, and their role in the ecology of the water body are introduced in this main section. Also, the…

  13. Control of Fish and Aquatic Plants.

    ERIC Educational Resources Information Center

    Hesser, R. B.; And Others

    This agriculture extension service publication from Pennsylvania State University is a handbook for the water body manager. The bulk of the contents deals with aquatic plant control. The different types of aquatic plants, their reproduction and growth, and their role in the ecology of the water body are introduced in this main section. Also, the…

  14. Aquatic Plant Control and Environmental Consequences.

    DTIC Science & Technology

    1982-01-01

    4), insects, and plant pathogens (2,3), but biological control reivains only a potential tool for large-scale control of aquatic weeds. Researchers in...fishes often do not feed selectively, yet there is no requirement for specific food selection by them. Use of Plant Pathogens k. Lack of information...on aquatic plant pathogens . Most work on plant pathogens , such as fungi, has been done on terrestrial species. Little is known with regard to methods

  15. Propagation and Production of Native Aquatic Plants

    DTIC Science & Technology

    2005-09-01

    ERDC/TN APCRP-EA-11 September 2005 Propagation and Production of Native Aquatic Plants by Gary Owen Dick , R. Michael Smart, and Joe R. Snow...small, protected plant colonies at strategic locations within unvegetated reservoirs (Smart and Dick 1999). Once successfully established, these...specific treatment of this information is given in Smart and Dick (1999). FACILITIES FOR OFF-SITE PRODUCTION: Production of aquatic plants requires

  16. Freshwater aquatic plant biomass production in Florida

    SciTech Connect

    Reddy, K.R.; Sutton, D.L.; Bowes, G.

    1983-01-01

    About 8% (1.2 million ha) of the total surface area of Florida is occupied by freshwater. Many of these water bodies are eutrophic. Nutrients present in these water bodies can be potentially used to culture aquatic plants as a possible feedstock for methane production. This paper summarizes the results of known research findings on biomass production potential of freshwater aquatic plants in Florida and identifies key research needs to improve the quality and quantity of biomass yields. Among floating aquatic plants, biomass yield potential was in the order of water-hyacinth > water lettuce > pennywort > salvinia > duckweed > azolla. Pennywort, duckweed, and azolla appear to perform well during the cooler months compared to other aquatic plants. Among emergent plants, biomass yield potential was in the order of southern wild rice > cattails > soft rush > bulrush. Cultural techniques, nutrient management, and environmental factors influencing the biomass yields were discussed. 68 references.

  17. Edaphic and light conditions of sympatric plant morphotypes in western Amazonia.

    PubMed

    Roncal, Julissa

    2014-01-01

    Here I present a dataset of edaphic and light conditions associated with the occurrence of sympatric morphotypes of Geonomamacrostachys (Arecaceae/Palmae), a candidate case study from Amazonia hypothesized to have evolved under ecological speciation. Transects were established in three lowland rainforests in Peru, and the abundance of each local morphotype of this species was recorded in a total area of 4.95 hectares. Composite soil samples and hemispherical photographs were taken along the transects were the species occurred to obtain information on soil nutrients, soil texture, and indirect measurements of light availability. The raw and summary tables disclose the characteristics of each study site and habitats within them, which could be useful to soil scientists, ecologists, and conservationists engaged in similar research activities or meta-analyses in Amazonia.

  18. Edaphic and light conditions of sympatric plant morphotypes in western Amazonia

    PubMed Central

    2014-01-01

    Abstract Here I present a dataset of edaphic and light conditions associated with the occurrence of sympatric morphotypes of Geonoma macrostachys (Arecaceae/Palmae), a candidate case study from Amazonia hypothesized to have evolved under ecological speciation. Transects were established in three lowland rainforests in Peru, and the abundance of each local morphotype of this species was recorded in a total area of 4.95 hectares. Composite soil samples and hemispherical photographs were taken along the transects were the species occurred to obtain information on soil nutrients, soil texture, and indirect measurements of light availability. The raw and summary tables disclose the characteristics of each study site and habitats within them, which could be useful to soil scientists, ecologists, and conservationists engaged in similar research activities or meta-analyses in Amazonia. PMID:24891831

  19. Aquatic Plant Water Quality Criteria

    EPA Science Inventory

    The USEPA, as stated in the Clean Water Act, is tasked with developing numerical Aquatic Life Critiera for various pollutants found in the waters of the United States. These criteria serve as guidance for States and Tribes to use in developing their water quality standards. The G...

  20. Aquatic Plant Water Quality Criteria

    EPA Science Inventory

    The USEPA, as stated in the Clean Water Act, is tasked with developing numerical Aquatic Life Critiera for various pollutants found in the waters of the United States. These criteria serve as guidance for States and Tribes to use in developing their water quality standards. The G...

  1. Aquatic Plant Control Research Program. Field methods to measure aquatic plant treatment method efficacy. Final report

    SciTech Connect

    Killgore, K.J.; Payne, B.S.

    1984-04-01

    The Aquatic Plant Control Research Program (APCRP) of the U.S. Army Engineer Waterways Experiment Station (WES) is developing field techniques to measure treatment efficacy and to determine site characteristics that influence the treatment efficacy. Treatment efficacy is considered a quantitative determination of the extent and duration of changes in problem aquatic plant populations attributable to the use of a treatment method (i.e., chemical, mechanical, biological, environmental). Depending on the plant species, efficacy can be determined or indicated by changes in biomass, areal distribution, or height of an aquatic plant in response to treatment. Aquatic plant biomass is sampled with a WES aquatic biomass sampler; areal distribution of aquatic plants is determined by aerial photography or with an electronic positioning system; and submersed aquatic plant height is measured with a fathometer (depth recorder) used with an electronic positioning and repositioning system (AGNAV). The APCRP has also developed field techniques to determine site characteristics that influence efficacy using commercially available instrumentation. This instrumentation can be used to measure treatment efficacy and to determine site characteristics simultaneously.

  2. Crassulacean acid metabolism in submerged aquatic plants

    USGS Publications Warehouse

    Keeley, Jon E.; Sybesme, C.

    1984-01-01

    CO2-fixation in the dark is known to occur in various organs of many plants. However, only in species possessing crassulacean acid metabolism (CAM) does dark CO2-fixation contribute substantially to the carbon economy of the plant. Until very recently CAM was known only from terrestrial species, largely drought adapted succulents. The discovery of CAM in the submerged aquatic fern ally Isoetes howellii (Isoetaceae)(Keeley 1981) adds a new dimension to our understanding of crassulacean acid metabolism. In this paper I will summarize 1) the evidence of CAM in Isoetes howellii, 2) the data on the distribution of CAM in aquatic species, and 3) the work to date on the functional significance of CAM in aquatic species.

  3. CAM Photosynthesis in Submerged Aquatic Plants

    USGS Publications Warehouse

    Keeley, J.E.

    1998-01-01

    Crassulacean acid metabolism (CAM) is a CO2-concentrating mechanism selected in response to aridity in terrestrial habitats, and, in aquatic environments, to ambient limitations of carbon. Evidence is reviewed for its presence in five genera of aquatic vascular plants, including Isoe??tes, Sagittaria, Vallisneria, Crassula, and Littorella. Initially, aquatic CAM was considered by some to be an oxymoron, but some aquatic species have been studied in sufficient detail to say definitively that they possess CAM photosynthesis. CO2-concentrating mechanisms in photosynthetic organs require a barrier to leakage; e.g., terrestrial C4 plants have suberized bundle sheath cells and terrestrial CAM plants high stomatal resistance. In aquatic CAM plants the primary barrier to CO2 leakage is the extremely high diffusional resistance of water. This, coupled with the sink provided by extensive intercellular gas space, generates daytime CO2(Pi) comparable to terrestrial CAM plants. CAM contributes to the carbon budget by both net carbon gain and carbon recycling, and the magnitude of each is environmentally influenced. Aquatic CAM plants inhabit sites where photosynthesis is potentially limited by carbon. Many occupy moderately fertile shallow temporary pools that experience extreme diel fluctuations in carbon availability. CAM plants are able to take advantage of elevated nighttime CO2 levels in these habitats. This gives them a competitive advantage over non-CAM species that are carbon starved during the day and an advantage over species that expend energy in membrane transport of bicarbonate. Some aquatic CAM plants are distributed in highly infertile lakes, where extreme carbon limitation and light are important selective factors. Compilation of reports on diel changes in titratable acidity and malate show 69 out of 180 species have significant overnight accumulation, although evidence is presented discounting CAM in some. It is concluded that similar proportions of the aquatic

  4. Aquatic Plant Control Research Program. Habitat Value of Aquatic Plants for Fishes

    DTIC Science & Technology

    1991-06-01

    If larger populations of fish are less sensitive to predator effects (Pitcher, Magurran, Winfield 1982) and to interspecific competitive restraints...9 AQUATIC PLANT CONTROLA D-A239 569 RESEARCH PROGRAM _ __ I I 11111 111111 H 1111 1 il TECHNICAL REPORT A-91-5 S Arm CorpSEi HABITAT VALUE OF...AQUATIC PLANTS FOR FISHES by K. Jack Killgore Environmental Laboratory DEPARTMENT OF THE ARMY Waterways Experiment Station, Corps of Engineers 30,,09 Halls

  5. Aquatic Plant Control Research Program: Effects of Water Chemistry on Submersed Aquatic Plants: A Synthesis

    DTIC Science & Technology

    1990-07-01

    plants exhibiting C4 photosynthesis, C is conserved by refixing photorespired CO2. These terres- trial adaptations have counterparts in the aquatic...such as low photorespiration rates and low CO2 compensation points. The advantages of this photosynthetic pathway include conservation of... photorespired C and efficient C assimilation under the high dissolved oxygen and low free CO2 concentrations common in dense submersed aquatic plant populations

  6. Aquatic Plant Genomics: Advances, Applications, and Prospects

    PubMed Central

    Li, Gaojie; Yang, Jingjing

    2017-01-01

    Genomics is a discipline in genetics that studies the genome composition of organisms and the precise structure of genes and their expression and regulation. Genomics research has resolved many problems where other biological methods have failed. Here, we summarize advances in aquatic plant genomics with a focus on molecular markers, the genes related to photosynthesis and stress tolerance, comparative study of genomes and genome/transcriptome sequencing technology. PMID:28900619

  7. Aquatic Plants and Animals as Ecosystem Engineers

    NASA Astrophysics Data System (ADS)

    Wotton, R. S.

    2005-05-01

    Studies on aquatic plants and animals focus on population dynamics, the structure of communities and the part played by organisms in food webs and other ecosystem processes. As Lawton and Jones point out in "Linking Species and Ecosystems", less attention is given to the role of organisms as ecosystem engineers, modifying the environment in which they live. Yet plants can have a profound effect on their surroundings, altering flow patterns and trapping large amounts of organic and inorganic material. Animals also affect aquatic ecosystems in many ways, both in building structures such as tubes and shelters, and in their feeding. For example, detritus feeders often produce large numbers of faecal pellets (and pseudofaeces in bivalves) and these are very different in size to the materials ingested. Pellets are deposited in masses over the bed of streams, lakes and the sea and therefore effect a translocation of nutrients. The action of plants and animals in altering their environment is likely to be a significant process in all water bodies, from both small to large scale.

  8. Map showing bathymetry and aquatic plants of Lake Waramaug, Connecticut

    USGS Publications Warehouse

    Kulp, Kenneth P.

    1981-01-01

    The Bathymetry of Lake Waramaug is shown at 5-foot intervals, and the location and identification of significant concentrations of aquatic plants is indicated. The bathymetry shows the lake to be relatively steep-sided and flat-bottomed, with a maximum depth of between 40 and 45 feet. Aquatic plants were confined to the edges of the lake in depths of less than 15 feet. Nine species of aquatic plants occcur in significant numbers in the lake. Lake bathymetric data were collected using a recording fathometer and sounding rod; aquatic plant data were collected by visual survey; and the collection of samples using a weed rake. (USGS)

  9. Trace element accumulation in aquatic plants: a literature review

    SciTech Connect

    Ganje, T.J.; Elseewi, A.A.; Page, A.L.

    1988-01-01

    Trace elements in sediments and its overlying waters are important constituents of an aquatic plant ecosystem. This review was undertaken to evaluate trace element accumulation in aquatic plants and ascertain to what extent sediment and its overlying waters play in trace element accumulation by aquatic plant species. Aquatic vascular plants tend to accumulate trace elements in relation to the trace element concentration of the water body and sediment in which they are grown and the extent of exposure to the water body. Trace element composition of bryophytes and algae is also closely related to composition of their aquatic environment. It is increasingly apparent that sediments and overlying waters alter the bioavailability of trace elements to aquatic plants in both natural and artificial water bodies, particularly where industrial and agricultural waters are discharged into waterways.

  10. The spatial distribution of acid phosphatase activity in ectomycorrhizal tissues depends on soil fertility and morphotype, and relates to host plant phosphorus uptake.

    PubMed

    Alvarez, Maricel; Huygens, Dries; Díaz, Leila Milena; Villanueva, Claudia Añazco; Heyser, Wolfgang; Boeckx, Pascal

    2012-01-01

    Acid phosphatase (ACP) enzymes are involved in the mobilization of soil phosphorus (P) and polyphosphate accumulated in the fungal tissues of ectomycorrhizal roots, thereby influencing the amounts of P that are stored in the fungus and transferred to the host plant. This study evaluated the effects of ectomycorrhizal morphotype and soil fertility on ACP activity in the extraradical mycelium (ACP(myc)), the mantle (ACP(mantle)) and the Hartig net region (ACP(Hartig)) of ectomycorrhizal Nothofagus obliqua seedlings. ACP activity was quantified in vivo using enzyme-labelled fluorescence-97 (ELF-97) substrate, confocal laser microscopy and digital image processing routines. There was a significant effect of ectomycorrhizal morphotype on ACP(myc), ACP(mantle) and ACP(Hartig), while soil fertility had a significant effect on ACP(myc) and ACP(Hartig). The relative contribution of the mantle and the Hartig net region to the ACP activity on the ectomycorrhizal root was significantly affected by ectomycorrhizal morphotype and soil fertility. A positive correlation between ACP(Hartig) and the shoot P concentration was found, providing evidence that ACP activity at the fungus:root interface is involved in P transfer from the fungus to the host. It is concluded that the spatial distribution of ACP in ectomycorrhizas varies as a function of soil fertility and colonizing fungus.

  11. Evaluating the feasibility of planting aquatic plants for habitat restoration in shallow Mississippi lakes

    USDA-ARS?s Scientific Manuscript database

    Planting aquatic plants is a technique used to restore native aquatic plant communities in lakes lacking aquatic plants. However, the feasibility of using this restoration technique in Mississippi lakes has not been evaluated. We conducted two exclosure experiments to evaluate the success of planti...

  12. Methane emissions to the atmosphere through aquatic plants

    NASA Technical Reports Server (NTRS)

    Sebacher, D. I.; Harriss, R. C.; Bartlett, K. B.

    1985-01-01

    The movement of methane (CH4) from anaerobic sediments through the leaves, stems, and flowers of aquatic plants and into the atmosphere was found to provide a significant pathway for the emission of CH4 from the aquatic substrates of flooded wetlands. Methane concentrations well above the surrounding ambient air levels were found in the mesophyll of 16 varies of aquatic plants and are attributed to transpiration, diffusion, and pressure-induced flow of gaseous CH4 from the roots when they are embedded in CH4-saturated anaerobic sediments. Methane emissions from the emergent parts of aquatic plants were measured using floating chamber techniques and by enclosing the plants in polyethylene bags of known volume. Concentration changes were monitored in the trapped air using syringes and gas chromatographic techniques. Vertical profiles of dissolved CH4 in sediment pore water surrounding the aquatic plants' rhizomes were obtained using an interstitial sampling technique. Methane emissions from the aquatic plants studied varied from 14.8 mg CH4/d to levels too low to be detectable. Rooted and unrooted freshwater aquatic plants were studied as well as saltwater and brackish water plants. Included in the experiment is detailed set of measurements on CH4 emissions from the common cattail (Typha latifolia). This paper illustrates that aquatic plants play an important gas exchange role in the C cycle between wetlands and the atmosphere.

  13. Methane emissions to the atmosphere through aquatic plants

    NASA Technical Reports Server (NTRS)

    Sebacher, D. I.; Harriss, R. C.; Bartlett, K. B.

    1985-01-01

    The movement of methane (CH4) from anaerobic sediments through the leaves, stems, and flowers of aquatic plants and into the atmosphere was found to provide a significant pathway for the emission of CH4 from the aquatic substrates of flooded wetlands. Methane concentrations well above the surrounding ambient air levels were found in the mesophyll of 16 varies of aquatic plants and are attributed to transpiration, diffusion, and pressure-induced flow of gaseous CH4 from the roots when they are embedded in CH4-saturated anaerobic sediments. Methane emissions from the emergent parts of aquatic plants were measured using floating chamber techniques and by enclosing the plants in polyethylene bags of known volume. Concentration changes were monitored in the trapped air using syringes and gas chromatographic techniques. Vertical profiles of dissolved CH4 in sediment pore water surrounding the aquatic plants' rhizomes were obtained using an interstitial sampling technique. Methane emissions from the aquatic plants studied varied from 14.8 mg CH4/d to levels too low to be detectable. Rooted and unrooted freshwater aquatic plants were studied as well as saltwater and brackish water plants. Included in the experiment is detailed set of measurements on CH4 emissions from the common cattail (Typha latifolia). This paper illustrates that aquatic plants play an important gas exchange role in the C cycle between wetlands and the atmosphere.

  14. Bioassay of Plant Growth Regulator Activity on Aquatic Plants

    DTIC Science & Technology

    1990-07-01

    weed submersed aquatic plants, hydrilla (Hydrilla verticillata Royle) and Eurasian watermilfoil (11yriophyllum splcatum L .). The gibberellin synthesis...Programs, Mr. J. L . Decell, Manager. The HQUSACE Technical Monitor for the APCRP was Mr. James W. Wolcott. The principal investigator for this work was...supervision of Dr. John Harrison, Chief, EL, and Mr. Donald L . Robey, Chief, ERSD, and under the direct supervision of Dr. Thomas L . Hart, Chief

  15. AQUATIC PLANT COMMUNITIES FOR IMPACT MONITORING AND ASSESSMENT

    EPA Science Inventory

    The studies revewed here suggest that both structural and functional assessments of aquatic plant communities are valuable tools in the determination of environmental impacts and water quality. I am not suggesting that aquatic plants be used in lieu of macronivertebrates or fish ...

  16. AQUATIC PLANT COMMUNITIES FOR IMPACT MONITORING AND ASSESSMENT

    EPA Science Inventory

    The studies revewed here suggest that both structural and functional assessments of aquatic plant communities are valuable tools in the determination of environmental impacts and water quality. I am not suggesting that aquatic plants be used in lieu of macronivertebrates or fish ...

  17. Energy from fresh and brackish water aquatic plants

    SciTech Connect

    Benemann, J.R.

    1981-01-01

    Aquatic plants can achieve relatively high biomass productivities when compared to terrestrial plants because they need not be water-stressed and can be optimally supplied with nutrients. Based on literature reports, productivities in southern US regions of about 40 to 60 t/ha-yr (dry weight basis) can be predicted for green algae or marsh plants and about 80 t/ha-yr for water hyacinth. Higher productivities may be possible in exceptionally favorable locations by assuming development of advanced cultivation technologies and genetic selection of improved strains. The lack of established cultivation systems and low-cost harvesting processes imposes great uncertainties on the cost of biomass production by aquatic plants. Three potentially practical aquatic biomass energy systems are chemicals production from microalgae, alcohol production from marsh plants, and methane production from water hyacinths. At present, aquatic plants are not being used commercially as a fuel source any place in the world. Nevertheless, it is clear that aquatic plants have potentially high biomass productivities and, specifically for the case of microalgae, could produce a high-quality, high-value biomass suitable for conversion to fuels and extraction of other products. A list of the relative advantages and disadvantages of aquatic plant energy systems in comparison with the concepts of terrestrial tree or herbaceous plant energy farming is given. Three favorable aspects of aquatic plant biomass systems should be stressed - the relative short-term research and development effort that will be required to determine the practical feasibility of such systems, the continuous production nature of such systems, and the relative independence of aquatic biomass systems from soil characteristics and weather fluctuations. The fast generation times of most aquatic plants allow rapid data acquisition, as compared to even short-rotation trees.

  18. Public Lakes, Private Lakeshore: Modeling Protection of Native Aquatic Plants

    NASA Astrophysics Data System (ADS)

    Schroeder, Susan A.; Fulton, David C.

    2013-07-01

    Protection of native aquatic plants is an important proenvironmental behavior, because plant loss coupled with nutrient loading can produce changes in lake ecosystems. Removal of aquatic plants by lakeshore property owners is a diffuse behavior that may lead to cumulative impacts on lake ecosystems. This class of behavior is challenging to manage because collective impacts are not obvious to the actors. This paper distinguishes positive and negative beliefs about aquatic plants, in models derived from norm activation theory (Schwartz, Adv Exp Soc Psychol 10:221-279, 1977) and the theory of reasoned action (Fishbein and Ajzen, Belief, attitude, intention, and behavior: an introduction to theory and research, Addison-Wesley, Boston 1975), to examine protection of native aquatic plants by Minnesota lakeshore property owners. We clarify how positive and negative evaluations of native aquatic plants affect protection or removal of these plants. Results are based on a mail survey ( n = 3,115). Results suggest that positive evaluations of aquatic plants (i.e., as valuable to lake ecology) may not connect with the global attitudes and behavioral intentions that direct plant protection or removal. Lakeshore property owners' behavior related to aquatic plants may be driven more by tangible personal benefits derived from accessible, carefully managed lakeshore than intentional action taken to sustain lake ecosystems. The limited connection of positive evaluations of aquatic plants to global attitudes and behavioral intentions may reflect either lack of knowledge of what actions are needed to protect lake health and/or unwillingness to lose perceived benefits derived from lakeshore property.

  19. Public lakes, private lakeshore: modeling protection of native aquatic plants.

    PubMed

    Schroeder, Susan A; Fulton, David C

    2013-07-01

    Protection of native aquatic plants is an important proenvironmental behavior, because plant loss coupled with nutrient loading can produce changes in lake ecosystems. Removal of aquatic plants by lakeshore property owners is a diffuse behavior that may lead to cumulative impacts on lake ecosystems. This class of behavior is challenging to manage because collective impacts are not obvious to the actors. This paper distinguishes positive and negative beliefs about aquatic plants, in models derived from norm activation theory (Schwartz, Adv Exp Soc Psychol 10:221-279, 1977) and the theory of reasoned action (Fishbein and Ajzen, Belief, attitude, intention, and behavior: an introduction to theory and research, Addison-Wesley, Boston 1975), to examine protection of native aquatic plants by Minnesota lakeshore property owners. We clarify how positive and negative evaluations of native aquatic plants affect protection or removal of these plants. Results are based on a mail survey (n = 3,115). Results suggest that positive evaluations of aquatic plants (i.e., as valuable to lake ecology) may not connect with the global attitudes and behavioral intentions that direct plant protection or removal. Lakeshore property owners' behavior related to aquatic plants may be driven more by tangible personal benefits derived from accessible, carefully managed lakeshore than intentional action taken to sustain lake ecosystems. The limited connection of positive evaluations of aquatic plants to global attitudes and behavioral intentions may reflect either lack of knowledge of what actions are needed to protect lake health and/or unwillingness to lose perceived benefits derived from lakeshore property.

  20. VASCULAR PLANTS AS ENGINEERS OF OXYGEN IN AQUATIC SYSTEMS

    EPA Science Inventory

    The impact of organisms on oxygen is one of the most dramatic examples of ecosystem engineering on Earth. In aquatic systems, which have much lower oxygen concentrations than the atmosphere, vascular aquatic plants can affect oxygen concentrations significantly not only on long t...

  1. VASCULAR PLANTS AS ENGINEERS OF OXYGEN IN AQUATIC SYSTEMS

    EPA Science Inventory

    The impact of organisms on oxygen is one of the most dramatic examples of ecosystem engineering on Earth. In aquatic systems, which have much lower oxygen concentrations than the atmosphere, vascular aquatic plants can affect oxygen concentrations significantly not only on long t...

  2. Master plan: Guntersville Reservoir Aquatic Plant Management. Executive summary

    SciTech Connect

    Not Available

    1992-12-31

    In 1989, Congress provided funding to start a five-year comprehensive project to manage aquatic plants in Guntersville Reservoir, to be jointly implemented by the US Army Corps of Engineers (Corps) and Tennessee Valley Authority (TVA). TVA serves as the overall project coordinator and is the lead agency for this project. Known as the Joint Agency Guntersville Project (JAGP), the project will test and demonstrate innovative management technologies, and incorporate the most effective technologies into a comprehensive aquatic plant management plan for Guntersville Reservoir. The JAGP is intended to serve as a National Demonstration Project for aquatic plant management. As part of this JAGP, the Master Plan for Aquatic Plant Management for the Guntersville Reservoir Project, Alabama-Tennessee is authorized by Corps Contract Number DACW62-90-C-0067.

  3. Biomarkers in aquatic plants: selection and utility.

    PubMed

    Brain, Richard A; Cedergreen, Nina

    2009-01-01

    This review emphasizes the predictive ability, sensitivity and specificity of aquatic plant biomarkers as biomonitoring agents of exposure and effect. Biomarkers of exposure are those that provide functional measures of exposure that are characterized at a sub-organism level. Biomarkers of effect require causal linkages between the biomarker and effects, measured at higher levels of biological organization. With the exception of pathway specific metabolites, the biomarkers assessed in this review show variable sensitivity and predictive ability that is often confounded by variations in growth conditions, rendering them unsuitable as stand alone indicators of environmental stress. The use of gene expression for detecting pollution has been, and remains immature; this immaturity derives from inadequate knowledge on predictive ability, sensitivity and specificity. Moreover, the ability to the detect mode of action of unknown toxicants using gene expression is not as clear-cut as initially hypothesized. The principal patterns in gene expression is not as clear-cut as initially hypothesized. The principal patterns in gene expression are generally derived from stress induced genes, rather than on ones that respond to substances with known modes of action (Baerson et al. 2005). Future developments in multivariate statistics and chemometric methods that enhance pattern analyses in ways that could produce a "fingerprint", may improve methods for discovering modes of action of unknown toxicants. Pathway specific metabolites are unambiguous, sensitive, correlate well to growth effects, and are relatively unaffected by growth conditions. These traits make them excellent biomarkers under both field and laboratory conditions. Changes in metabolites precede visible growth effects; therefore, measuring changes in metabolite concentrations (Harring et al. 1998; Shaner et al. 2005). The metabolic phase I enzymes (primarily associated with P-450 activity) are non-specific biomarkers

  4. Biotechnological potential of aquatic plant-microbe interactions.

    PubMed

    Stout, L; Nüsslein, K

    2010-06-01

    The rhizosphere in terrestrial systems is the region of soil surrounding plant roots where there is increased microbial activity; in aquatic plants, this definition may be less clear because of diffusion of nutrients in water, but there is still a zone of influence by plant roots in this environment [1]. Within that zone chemical conditions differ from those of the surrounding environment as a consequence of a range of processes that were induced either directly by the activity of plant roots or by the activity of rhizosphere microflora. Recently, there are a number of new studies related to rhizospheres of aquatic plants and specifically their increased potential for remediation of contaminants, especially remediation of metals through aquatic plant-microbial interaction.

  5. Aquatic plant surface as a niche for methanotrophs

    PubMed Central

    Yoshida, Naoko; Iguchi, Hiroyuki; Yurimoto, Hiroya; Murakami, Akio; Sakai, Yasuyoshi

    2014-01-01

    This study investigated the potential local CH4 sink in various plant parts as a boundary environment of CH4 emission and consumption. By comparing CH4 consumption activities in cultures inoculated with parts from 39 plant species, we observed significantly higher consumption of CH4 associated with aquatic plants than other emergent plant parts such as woody plant leaves, macrophytic marine algae, and sea grass. In situ activity of CH4 consumption by methanotrophs associated with different species of aquatic plants was in the range of 3.7–37 μmol·h−1·g−1 dry weight, which was ca 5.7–370-fold higher than epiphytic CH4 consumption in submerged parts of emergent plants. The qPCR-estimated copy numbers of the particulate methane monooxygenase-encoding gene pmoA were variable among the aquatic plants and ranged in the order of 105–107 copies·g−1 dry weight, which correlated with the observed CH4 consumption activities. Phylogenetic identification of methanotrophs on aquatic plants based on the pmoA sequence analysis revealed a predominance of diverse gammaproteobacterial type-I methanotrophs, including a phylotype of a possible plant-associated methanotroph with the closest identity (86–89%) to Methylocaldum gracile. PMID:24550901

  6. Aquatic plant surface as a niche for methanotrophs.

    PubMed

    Yoshida, Naoko; Iguchi, Hiroyuki; Yurimoto, Hiroya; Murakami, Akio; Sakai, Yasuyoshi

    2014-01-01

    This study investigated the potential local CH4 sink in various plant parts as a boundary environment of CH4 emission and consumption. By comparing CH4 consumption activities in cultures inoculated with parts from 39 plant species, we observed significantly higher consumption of CH4 associated with aquatic plants than other emergent plant parts such as woody plant leaves, macrophytic marine algae, and sea grass. In situ activity of CH4 consumption by methanotrophs associated with different species of aquatic plants was in the range of 3.7-37 μmol·h(-1)·g(-1) dry weight, which was ca 5.7-370-fold higher than epiphytic CH4 consumption in submerged parts of emergent plants. The qPCR-estimated copy numbers of the particulate methane monooxygenase-encoding gene pmoA were variable among the aquatic plants and ranged in the order of 10(5)-10(7) copies·g(-1) dry weight, which correlated with the observed CH4 consumption activities. Phylogenetic identification of methanotrophs on aquatic plants based on the pmoA sequence analysis revealed a predominance of diverse gammaproteobacterial type-I methanotrophs, including a phylotype of a possible plant-associated methanotroph with the closest identity (86-89%) to Methylocaldum gracile.

  7. Bioremoval of toxic elements with aquatic plants and algae

    SciTech Connect

    Wang, T.C.; Ramesh, G.; Weissman, J.C.; Varadarajan, R.; Benemann, J.R.

    1995-12-31

    Aquatic plants were screened to evaluate their ability to adsorb dissolved metals. The plants screened included those that are naturally immobilized (attached algae and rooted plants) and those that could be easily separated from suspension (filamentous microalgae, macroalgae, and floating plants). Two plants were observed to have high adsorption capabilities for cadmium (Cd) and zinc (Zn) removal: one blue green filamentous alga of the genus Phormidium and one aquatic rooted plant, water milfoil (Myriophyllum spicatum). These plants could also reduce the residual metal concentration to 0.1 mg/L or less. Both plants also exhibited high specific adsorption for other metals (Pb, Ni, and Cu) both individually and in combination. Metal concentrations were analyzed with an atomic absorption spectrophotometer (AAS).

  8. Aquatic Plant Control Research Program. Microbiological Control of Eurasian Watermilfoil.

    DTIC Science & Technology

    1983-06-01

    of enzymes produced by microorganisms occurring naturally on the surface tissues of two species of watermil- foil, Nyriophyllum spicatum and N...the environment, we would isolate microorganisms native to the plant -dominated zone or phyllosphere of the aquatic plant and, by simple manipulation...confirmed by the isolation of approximately 65 percent of the original inoculum numbers by the time of plant harvest. Thus, plant -dependent microorganisms

  9. Aquatic and wetland vascular plants of the northern Great Plains

    Treesearch

    Gary E. Larson

    1993-01-01

    A taxonomic treatment of aquatic and wetland vascular plants has been developed as a tool for identifying over 500 plant species inhabiting wetlands of the northern Great Plains region. The treatment provides dichotomous keys and botanical descriptions to facilitate identification of all included taxa. Illustrations are also provided for selected species. Geographical...

  10. Herbivore regulation of plant abundance in aquatic ecosystems.

    PubMed

    Wood, Kevin A; O'Hare, Matthew T; McDonald, Claire; Searle, Kate R; Daunt, Francis; Stillman, Richard A

    2017-05-01

    Herbivory is a fundamental process that controls primary producer abundance and regulates energy and nutrient flows to higher trophic levels. Despite the recent proliferation of small-scale studies on herbivore effects on aquatic plants, there remains limited understanding of the factors that control consumer regulation of vascular plants in aquatic ecosystems. Our current knowledge of the regulation of primary producers has hindered efforts to understand the structure and functioning of aquatic ecosystems, and to manage such ecosystems effectively. We conducted a global meta-analysis of the outcomes of plant-herbivore interactions using a data set comprised of 326 values from 163 studies, in order to test two mechanistic hypotheses: first, that greater negative changes in plant abundance would be associated with higher herbivore biomass densities; second, that the magnitude of changes in plant abundance would vary with herbivore taxonomic identity. We found evidence that plant abundance declined with increased herbivore density, with plants eliminated at high densities. Significant between-taxa differences in impact were detected, with insects associated with smaller reductions in plant abundance than all other taxa. Similarly, birds caused smaller reductions in plant abundance than echinoderms, fish, or molluscs. Furthermore, larger reductions in plant abundance were detected for fish relative to crustaceans. We found a positive relationship between herbivore species richness and change in plant abundance, with the strongest reductions in plant abundance reported for low herbivore species richness, suggesting that greater herbivore diversity may protect against large reductions in plant abundance. Finally, we found that herbivore-plant nativeness was a key factor affecting the magnitude of herbivore impacts on plant abundance across a wide range of species assemblages. Assemblages comprised of invasive herbivores and native plant assemblages were associated with

  11. Biological Fenton's oxidation of pentachlorophenol by aquatic plants.

    PubMed

    Reis, Andre Rodrigues dos; Kyuma, Yukako; Sakakibara, Yutaka

    2013-12-01

    This study proposes a new treatment method to decompose persistent chemicals such as pentachlorophenol (PCP) in water, utilizing hydrogen peroxide present in aquatic plants to proceed the biological Fenton reaction. PCP was not effectively removed by aquatic plants. However, by adding 2.8 mM of Fe(2+), there was a rapid removal of PCP while at the same time consumption of endogenous hydrogen peroxide occurred. It was observed the increase of chloride ions formation in water-confirming the complete degradation of PCP. These results demonstrated that PCP was oxidized through a biological Fenton reaction, and hydrogen peroxide in aquatic plants was a key endogenous substance in treatment of refractory toxic pollutants.

  12. Late Cretaceous Aquatic Plant World in Patagonia, Argentina

    PubMed Central

    Cúneo, N. Rubén; Gandolfo, María A.; Zamaloa, María C.; Hermsen, Elizabeth

    2014-01-01

    In this contribution, we describe latest Cretaceous aquatic plant communities from the La Colonia Formation, Patagonia, Argentina, based on their taxonomic components and paleoecological attributes. The La Colonia Formation is a geological unit deposited during a Maastrichtian-Danian transgressive episode of the South Atlantic Ocean. This event resulted in the deposition of a series of fine-grained sediments associated with lagoon systems occurring along irregular coastal plains in northern Patagonia. These deposits preserved a diverse biota, including aquatic and terrestrial plants and animals. The aquatic macrophytes can be broadly divided into two groups: free-floating and rooted, the latter with emergent or floating leaves. Free-floating macrophytes include ferns in Salviniaceae (Azolla and Paleoazolla) and a monocot (Araceae). Floating microphytes include green algae (Botryoccocus, Pediastrum and Zygnemataceae). Among the rooted components, marsileaceous water ferns (including Regnellidium and an extinct form) and the eudicot angiosperm Nelumbo (Nelumbonaceae) are the dominant groups. Terrestrial plants occurring in the vegetation surrounding the lagoons include monocots (palms and Typhaceae), ferns with affinities to Dicksoniaceae, conifers, and dicots. A reconstruction of the aquatic plant paleocommuniy is provided based on the distribution of the fossils along a freshwater horizon within the La Colonia Formation. This contribution constitutes the first reconstruction of a Cretaceous aquatic habitat for southern South America. PMID:25148081

  13. Late cretaceous aquatic plant world in Patagonia, Argentina.

    PubMed

    Cúneo, N Rubén; Gandolfo, María A; Zamaloa, María C; Hermsen, Elizabeth

    2014-01-01

    In this contribution, we describe latest Cretaceous aquatic plant communities from the La Colonia Formation, Patagonia, Argentina, based on their taxonomic components and paleoecological attributes. The La Colonia Formation is a geological unit deposited during a Maastrichtian-Danian transgressive episode of the South Atlantic Ocean. This event resulted in the deposition of a series of fine-grained sediments associated with lagoon systems occurring along irregular coastal plains in northern Patagonia. These deposits preserved a diverse biota, including aquatic and terrestrial plants and animals. The aquatic macrophytes can be broadly divided into two groups: free-floating and rooted, the latter with emergent or floating leaves. Free-floating macrophytes include ferns in Salviniaceae (Azolla and Paleoazolla) and a monocot (Araceae). Floating microphytes include green algae (Botryoccocus, Pediastrum and Zygnemataceae). Among the rooted components, marsileaceous water ferns (including Regnellidium and an extinct form) and the eudicot angiosperm Nelumbo (Nelumbonaceae) are the dominant groups. Terrestrial plants occurring in the vegetation surrounding the lagoons include monocots (palms and Typhaceae), ferns with affinities to Dicksoniaceae, conifers, and dicots. A reconstruction of the aquatic plant paleocommuniy is provided based on the distribution of the fossils along a freshwater horizon within the La Colonia Formation. This contribution constitutes the first reconstruction of a Cretaceous aquatic habitat for southern South America.

  14. Cytochemical and ultrastructural aspects of aquatic carnivorous plant turions.

    PubMed

    Płachno, Bartosz J; Adamec, Lubomír; Kozieradzka-Kiszkurno, Małgorzata; Swiątek, Piotr; Kamińska, Iwona

    2014-11-01

    Turions, which are modified shoot apices, are vegetative, dormant overwintering organs produced by perennial aquatic plants. In this study, the turion cytochemistry and ultrastructure of Aldrovanda vesiculosa, Utricularia vulgaris and U. stygia were compared with particular emphasis placed on storage substances. These three aquatic, rootless carnivorous plant species were studied at the end of their winter dormancy. At this stage, the turions of all species had starch as their main storage material. In contrast with A. vesiculosa, Utricularia turions were rich in protein storage vacuoles, and proteins were also accumulated as crystalline inclusions in the nuclei. All examined species accumulated lipid droplets in cells of epidermal glands.

  15. Transformation of TNT by Aquatic Plants,

    DTIC Science & Technology

    1996-01-01

    present knowledge of metal to absorb, concentrate and precipitate toxic metals from polluted hyperaccumulator plants in order to identify those with the...Plant University of Sheffield, UK Sciences, University of Sheffield, UK Session I n a Cot.minans 1:45 Metal -Accumulating Plants: The Biological Resource...University University of Sheffield, UK Toxic metal pollution of waters and soils is a major environmental All plants take up metals to varying degrees

  16. A proposed aquatic plant community biotic index for Wisconsin lakes

    USGS Publications Warehouse

    Nichols, S.; Weber, S.; Shaw, B.

    2000-01-01

    The Aquatic Macrophyte Community Index (AMCI) is a multipurpose tool developed to assess the biological quality of aquatic plant communities in lakes. It can be used to specifically analyze aquatic plant communities or as part of a multimetric system to assess overall lake quality for regulatory, planning, management, educational, or research purposes. The components of the index are maximum depth of plant growth; percentage of the littoral zone vegetated; Simpson's diversity index; the relative frequencies of submersed, sensitive, and exotic species; and taxa number. Each parameter was scaled based on data distributions from a statewide database, and scaled values were totaled for the AMCI value. AMCI values were grouped and tested by ecoregion and lake type (natural lakes and impoundments) to define quality on a regional basis. This analysis suggested that aquatic plant communities are divided into four groups: (1) Northern Lakes and Forests lakes and impoundments, (2) North-Central Hardwood Forests lakes and impoundments, (3) Southeastern Wisconsin Till Plains lakes, and (4) Southeastern Wisconsin Till Plains impoundments, Driftless Area Lakes, and Mississippi River Backwater lakes. AMCI values decline from group 1 to group 4 and reflect general water quality and human use trends in Wisconsin. The upper quartile of AMCI values in any region are the highest quality or benchmark plant communities. The interquartile range consists of normally impacted communities for the region and the lower quartile contains severely impacted or degraded plant communities. When AMCI values were applied to case studies, the values reflected known impacts to the lakes. However, quality criteria cannot be used uncritically, especially in lakes that initially have low nutrient levels.The Aquatic Macrophyte Community Index (AMCI) is a multipurpose tool developed to assess the biological quality of aquatic plant communities in lakes. It can be used to specifically analyze aquatic plant

  17. A co-beneficial system using aquatic plants: bioethanol production from free-floating aquatic plants used for water purification.

    PubMed

    Soda, S; Mishima, D; Inoue, D; Ike, M

    2013-01-01

    A co-beneficial system using constructed wetlands (CWs) planted with aquatic plants is proposed for bioethanol production and nutrient removal from wastewater. The potential for bioethanol production from aquatic plant biomass was experimentally evaluated. Water hyacinth and water lettuce were selected because of their high growth rates and easy harvestability attributable to their free-floating vegetation form. The alkaline/oxidative pretreatment was selected for improving enzymatic hydrolysis of the aquatic plants. Ethanol was produced with yields of 0.14-0.17 g-ethanol/ g-biomass in a simultaneous saccharification and fermentation mode using a recombinant Escherichia coli strain or a typical yeast strain Saccharomyces cerevisiae. Subsequently, the combined benefits of the CWs planted with the aquatic plants for bioethanol production and nutrient removal were theoretically estimated. For treating domestic wastewater at 1,100 m(3)/d, it was inferred that the anoxic-oxic activated sludge process consumes energy at 3,200 MJ/d, whereas the conventional activated sludge process followed by the CW consumes only 1,800 MJ/d with ethanol production at 115 MJ/d.

  18. State of South Carolina Cooperative Aquatic Plant Control Program.

    DTIC Science & Technology

    1980-11-01

    waters of South Carolina in the in- terest of navigation, flood control, agriculture, fish and wildlife, public health , and other related purposes...navigation, flood control, agriculture, fish and wildlife, public health , and other related purposes. Target species include alligator weed, Brazilian...of aquatic plants would * improve drainage and navigation, reduce potential public health problems by. * reducing mosquito breeding areas, and improve

  19. Hydrothermal processing of biomass from invasive aquatic plants

    Treesearch

    W. James Catallo; Todd F. Shupe; Thomas L. Eberhardt

    2008-01-01

    The purpose of this study was to examine the hydrothermal (HT) treatment of three invasive aquatic plants (i.e., Lemna sp., Hydrilla sp., and Eichhornia sp.) with respect to the generation of semi-volatile hydrocarbon product mixtures and biomass volume reduction. Identical HT treatments yielded similar semi-...

  20. Relationships Between Fish and Aquatic Plants: A Plan of Study

    DTIC Science & Technology

    1993-10-01

    has been used to de- fine differences in plant distribution, abundance, and species composition (Forsberg 1959; Edwards and Moore 1975; Cassani and...McCreary. 1985. Effects of fish nests on pattern and zonation of submersed macrophytes in a softwater lake. Aquat. Bot. 22:21-32. Cassani , J. R., and W

  1. Plant bioindicators for polycyclic aromatic hydrocarbon toxicity in aquatic microcosms

    SciTech Connect

    Gensemer, R.W.; Solomon, K.R.; Day, K.E.; Hodson, P.V.; Servos, M.R.; Greenberg, B.M.

    1994-12-31

    Plant bioindicators are being developed to assess the effects of polycyclic aromatic hydrocarbons (PAHs) in experimental aquatic ecosystems. The approach is to develop and test biomarker assays that are specifically predictive of ecological events at the population and/or community levels of organization in artificial aquatic microcosms. PAH mixtures were introduced into a series of aquatic microcosms using the wood preservative creosote as a PAH source. The authors applied creosote at five dosage levels designed to simulate conductions observed at highly contaminated sites. The growth and biomass of phytoplankton, periphyton, and macrophytes were then measured throughout the growing season, and compared to one or more biomarker assays used to detect PAH contamination. Preliminary results using fluorescence induction on aquatic macrophytes suggest that PAHs can significantly inhibit photosynthesis at even modest concentrations 1--4 hours after exposure. This assay thus is not only a sensitive indicator of PAH exposure, but may also describe mechanisms of PAH toxicity that ultimately reduce biomass or population growth for aquatic plants in these microcosms.

  2. Sensitivity of aquatic plants to the herbicide metsulfuron-methyl.

    PubMed

    Cedergreen, N Nina; Streibig, Jens C; Spliid, Niels Henrik

    2004-02-01

    The sensitivity of 12 aquatic plant species to the herbicide metsulfuron-methyl was tested in microcosm experiments under two growth conditions. As reference species, barley (Hordeum vulgare) and oil-seed rape (Brassica napus) were grown with their roots submerged in the microcosms. Two response variables were chosen: relative growth rate and specific leaf area (SLA). SLA was the most sensitive response variable, with 11 of the 12 aquatic species responding to the herbicide. EC(50) values varied 56-fold between species, with the commonly used aquatic test species Lemna minor being one of the most sensitive. Fast-growing species with a small exposed leaf area proved to be more sensitive to the herbicide than slow growing species with a large exposed leaf area, which was believed to be primarily due to variations in growth rates rather than to variations in exposed leaf area. The aquatic plants displayed high tolerance in growth to metsulfuron compared with the sensitive crop oil-seed rape. Hence, possible spray-drift events and leaching of the herbicide applied at agricultural rates are not considered to have a large impact on the growth of the aquatic flora tested.

  3. Aquatic Plants and Wastewater Treatment (an Overview)

    NASA Technical Reports Server (NTRS)

    Wolverton, B. C.

    1986-01-01

    The technology for using water hyacinth to upgrade domestic sewage effluent from lagoons and other wastewater treatment facilities to secondary and advanced secondary standards has been sufficiently developed to be used where the climate is warm year round. The technology of using emergent plants such as bulrush combined with duckweed is also sufficiently developed to make this a viable wastewater treatment alternative. This system is suited for both temperate and semi-tropical areas found throughout most of the U.S. The newest technology in artificial marsh wastewater treatment involves the use of emergent plant roots in conjunction with high surface area rock filters. Smaller land areas are required for these systems because of the increased concentration of microorganisms associated with the rock and plant root surfaces. Approximately 75 percent less land area is required for the plant-rock system than is required for a strict artificial wetland to achieve the same level of treatment.

  4. Long-term effects of heavy metals on aquatic plants

    SciTech Connect

    van der Werff, M.; Pruyt, M.J.

    1982-01-01

    In long-term experiments lasting up to 73 days the effect of rather low levels of zinc, copper, lead and cadmium on the growth and metal uptake was studied by investigating four aquatic plant species: Elodea nuttallii, Callitriche plataycarpa, Spirodela polyrhiza and Lemma gibba. Except Elodea, which was already very sensitive to 5 ..mu..mol Cu 1/sup -1/, no differentiation in growth or mortality could be detected depending on species or elements. There was a clear differentiation between the uptake levels of the heavy metals with regard to the plant species, resulting in a higher heavy metal content in the submerged species in comparison to the floating ones. For zinc, lead and cadmium, an equal ratio was detected between the concentration in the medium and in the plant tissue independent of the plant species. The involvement of roots in element absorption by aquatic plants and the possibility of using aquatic plants as indicators of heavy metal pollution in Dutch waters are discussed.

  5. Aquatic Plant Control Research Program: Aquatic Plant Identification and Herbicide Use Guide. Volume 2. Aquatic Plants and Susceptibility to Herbicides

    DTIC Science & Technology

    1988-11-01

    sedges , and rushes are the most common herbaceous components of the freshwater marsh. FS - Freshwater Swamp. This habitat consists of those areas where... sedges , rushes) heart-shaped monoeclous - having staminate and corolla - the inner, usually colored pistillate flowers on the same plant whorl of the...grasses, sedges , and rushes oblanceolate - reverse lance-shaped; cuticle - a waxy, protective layer on broadest at apex, gradually tapering the surfaces

  6. 33 CFR Appendix A to Part 273 - Aquatic Plant Control Program Legislative Authority

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ..., and other obnoxious aquatic plant growths, from the navigable waters, tributary streams, connecting... 33 Navigation and Navigable Waters 3 2010-07-01 2010-07-01 false Aquatic Plant Control Program... OF THE ARMY, DEPARTMENT OF DEFENSE AQUATIC PLANT CONTROL Pt. 273, App. A Appendix A to Part 273...

  7. 33 CFR Appendix A to Part 273 - Aquatic Plant Control Program Legislative Authority

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ..., and other obnoxious aquatic plant growths, from the navigable waters, tributary streams, connecting... 33 Navigation and Navigable Waters 3 2014-07-01 2014-07-01 false Aquatic Plant Control Program... OF THE ARMY, DEPARTMENT OF DEFENSE AQUATIC PLANT CONTROL Pt. 273, App. A Appendix A to Part 273...

  8. 33 CFR Appendix B to Part 273 - Information Requirements for Aquatic Plant Control Program Reports

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Aquatic Plant Control Program Reports B Appendix B to Part 273 Navigation and Navigable Waters CORPS OF ENGINEERS, DEPARTMENT OF THE ARMY, DEPARTMENT OF DEFENSE AQUATIC PLANT CONTROL Pt. 273, App. B Appendix B to Part 273—Information Requirements for Aquatic Plant Control Program Reports 1. Location and...

  9. Toxicity and removal of pesticides by selected aquatic plants.

    PubMed

    Olette, Rachel; Couderchet, Michel; Biagianti, Sylvie; Eullaffroy, Philippe

    2008-02-01

    Pesticides are being detected in water bodies on an increasingly frequent basis. The present study focused on the phytoremediation potential of selected aquatic plants to remove phytosanitary products from contaminated water. We investigated the uptake capacity of Lemna minor (L. minor), Elodea canadensis (E. canadensis) and Cabomba aquatica (C. aquatica) on three pesticides: copper sulphate (fungicide), flazasulfuron (herbicide) and dimethomorph (fungicide). Pesticide toxicity was evaluated by exposing plants to five concentrations (0-1 mg L(-1)) in culture media for 7d using chlorophyll fluorescence as a biomarker. The toxicity of the contaminants was the same for all the aquatic plants studied and occurred in this descending order of toxicity: flazasulfuron>copper>dimethomorph. We found that L. minor had the most efficient uptake capacity, followed by E. canadensis and then C. aquatica. The maximum removal rate (microg g(-1)fresh weight d(-1)) of copper, flazasulfuron and dimethomorph was 30, 27 and 11, respectively.

  10. Aquatic Plant Management Program current status and seasonal workplan

    SciTech Connect

    Burns, E.R.; Bates, A.L.; Webb, D.H.

    1993-07-01

    The objective of the TVA Aquatic Plant Management Program is to support in an environmentally and economically responsible manner, the balanced multiple uses of the water resource of the Tennessee Valley. This is accomplished by following an integrated approach to prevent introduction and spread of noxious species, documenting occurrence and spread of existing species, and suppressing or eliminating problems in designated high use areas. It is not the TVA objective, nor is it biologically feasible and prudent to eliminate all aquatic vegetation. Aerial photography, helicopter reconnaissance, and field surveys are used to assess distributions and abundance of various aquatic macrophytes. Water level fluctuations are supplemented by herbicide applications to control undesirable vegetation. Investigations are conducted to evaluate water level fluctuation schemes, as well as biological, mechanical, and alternative chemical control techniques which offer potential for more environmentally compatible and cost-effective management operations.

  11. A Proposed Aquatic Plant Community Biotic Index for Wisconsin Lakes

    NASA Astrophysics Data System (ADS)

    Nichols, Stanley; Weber, Steven; Shaw, Byron

    2000-11-01

    The Aquatic Macrophyte Community Index (AMCI) is a multipurpose tool developed to assess the biological quality of aquatic plant communities in lakes. It can be used to specifically analyze aquatic plant communities or as part of a multimetric system to assess overall lake quality for regulatory, planning, management, educational, or research purposes. The components of the index are maximum depth of plant growth; percentage of the littoral zone vegetated; Simpson's diversity index; the relative frequencies of submersed, sensitive, and exotic species; and taxa number. Each parameter was scaled based on data distributions from a statewide database, and scaled values were totaled for the AMCI value. AMCI values were grouped and tested by ecoregion and lake type (natural lakes and impoundments) to define quality on a regional basis. This analysis suggested that aquatic plant communities are divided into four groups: (1) Northern Lakes and Forests lakes and impoundments, (2) North-Central Hardwood Forests lakes and impoundments, (3) Southeastern Wisconsin Till Plains lakes, and (4) Southeastern Wisconsin Till Plains impoundments, Driftless Area Lakes, and Mississippi River Backwater lakes. AMCI values decline from group 1 to group 4 and reflect general water quality and human use trends in Wisconsin. The upper quartile of AMCI values in any region are the highest quality or benchmark plant communities. The interquartile range consists of normally impacted communities for the region and the lower quartile contains severely impacted or degraded plant communities. When AMCI values were applied to case studies, the values reflected known impacts to the lakes. However, quality criteria cannot be used uncritically, especially in lakes that initially have low nutrient levels.

  12. Phytoremediation of munitions by aquatic plants

    SciTech Connect

    Wolfe, N.L.; McCutcheon, S.M.; Carriera, L.H.; Ou, T.

    1995-12-31

    An isolated enzyme system from plants and the whole plant containing the enzyme have been shown to degrade TNT, RDX and HMX to environmental acceptable compounds. As a result of detailed laboratory studies, the general process is on a sound scientific basis. The overall process along with the analytical procedures for chemical analysis are described. The process has been scaled up in the field in static systems. The results have been consistent with the laboratory findings. In the field pilot study employing a TNT contaminated sediment/water/parrot feather system, it was possible to drive the aqueous phase TNT and the transient amino intermediates to below 0.1 ppm (the limit of detection of these studies). The studies have been scaled up in the laboratory using emerged macrophytes in a flow through system.

  13. State of Washington Aquatic Plant Management Program

    DTIC Science & Technology

    1979-10-01

    waterfowl diet. A digestive tract analysis of several waterfowl species done by Florshutz (1973) between 1968 and 1971 in Virginia and North Carolina...uustablei and the meal made from milfoil pigmented broilers (Smith, 1971). The estimated c~ost/acre of mechanical harvesting (assuming two cuttings per... digestive tract, large amounts of incom- pletely digested plant material are returned to the water. The nutrients contained in this mate’eial are added to

  14. Aquatic phytoremendiation: Algae and aquatic plants for removal of toxic elements

    SciTech Connect

    Benemann, J.R.

    1996-12-31

    A study to test several species of plants for heavy metal bioremoval is very briefly described. Adsorption isotherms were determined for cadmium, zinc, lead, nickel, and copper by measuring the amounts adsorbed by the biomass over a range of residual metal concentrations. Numerical results presented include adsorption characteristics of aquatic plants at pH 5 and specific adsorption of cadmium onto various biomass. The two best species were Phormidium, a blue-green alga, and Myriophyllum spicatum, water milfoil. The maximum metal ion absorbed the the minimal residual metal concentrations achieved allow estimation of the amount of biomass required to achieve a desired treatment level.

  15. Aquatic Plant Control Research Program. Proceedings, Annual Meeting, Aquatic Plant Control Research Program (23rd) Held in West Palm Beach, Florida on 14-17 November 1988

    DTIC Science & Technology

    1989-06-01

    plants in the treatment area. One potential alternative to current aquatic weed control strategies is to alter natural plant hormonal processes and...the process of selecting a treatment technique for application. Some example questions are (a) When will this particular aquatic plant population reach...toward the water surface. This process continues until *University of Southern Mississippi, Department of Biological Sciences, Hattiesburg

  16. Selection of candidate aquatic high plants as producer of closed aquatic ecosystem

    NASA Astrophysics Data System (ADS)

    Wang, Gaohong; Hao, Zongjie; Liu, Yongding

    Controlled Ecological Life Support Systems (CELSS) is very important for long-term manned space flight. Aquatic organism was regarded to be suitable for this study because of their great adaptation to the weightless condition which approximate to their wild condition in water. In order to study of operation of CELSS in space, the first step is to choose good candidate species for study. In this report, we compared the characteristics of nutrient content, growth and suitability with animals among five types of aquatic high plants including Ceratophyllum demersum L., Vallisneria spiralis L., Hydrilla verticillata Royle, Brasenia schreberi, Wolfia arrhiza under control condition. It was found that B. schreberi had the best nutrients content, but it growth depended on gas interface which may be a big problem in microgravity. C. demersum and W. arrhiza had the better nutrient content than other types, and V. spiralis and H. verticillata had the worst nutrient content. The closed aquatic system can provided condition for the growth of other plants than B. schreberi. So we selected C. demersum and W. arrhiza as the candidate of producer for establish Closed Aquatic Ecosystem. We also established a simple system& by housing three small freshwater snails (Bulinus australianus) and C. demersum in a 500mL box with light and temperature control. The values about pH, oxygen concentration, temperature and light had been acquired by sensors in real time for about 3 month. It was found that plant's biomass increased for several days and then leveled off and the snails survive, and the atmosphere and biomass for food met snails' requirement during experiments.

  17. Method for treating wastewater using microorganisms and vascular aquatic plants

    NASA Technical Reports Server (NTRS)

    Wolverton, B. C. (Inventor)

    1983-01-01

    A method for treating wastewater compresses subjecting the wastewater to an anaerobic setting step for at least 6 hours and passing the liquid effluent from the anaerobic settling step through a filter cell in an upflow manner. There the effluent is subjected first to the action of anaerobic and facultative microorganisms, and then to the action of aerobic microorganisms and the roots of at least one vascular aquatic plant.

  18. Removal of fluoride contamination in water by three aquatic plants.

    PubMed

    Karmakar, Sukalpa; Mukherjee, Joydeep; Mukherjee, Somnath

    2016-01-01

    Phytoremediation, popularly known as 'green technology' has been employed in the present investigation to examine the potential of fluoride removal from water by some aquatic plants. Fluoride contamination in drinking water is very much prevalent in different parts of the world including India. Batch studies were conducted using some aquatic plants e.g., Pistia stratiotes, Eichhornia crassipes, and Spirodela polyrhiza which profusely grow in natural water bodies. The experimental data exhibited that all the above three aquatic floating macrophytes could remove fluoride to some relative degree of efficiency corresponding to initial concentration of fluoride 3, 5, 10, 20 mg/l after 10 days exposure time. Result showed that at lower concentration level i.e., 3 mg/L removal efficiency of Pistia stratiotes (19.87%) and Spirodela polyrhiza (19.23%) was found to be better as compared to Eichhornia crassipes (12.71%). Some of the physiological stress induced parameters such as chlorophyll a, chlorophyll b, total chlorophyll, carotenoid, total protein, catalase, and peroxidase were also studied to explore relative damage within the cell. A marginal stress was imparted among all the plants for lower concentration values (3 mg/L), whereas at 20 mg/l, maximum damage was observed.

  19. Effects of invasive species on plant communities: an example using submersed aquatic plants at the regional level

    USDA-ARS?s Scientific Manuscript database

    Submerged aquatic plants have a key role in maintaining functioning aquatic ecosystems through their effects in the hydrological regime, sedimentation, nutrient cycling and habitats of associated fauna. Modifications of aquatic plant communities, as for example through the introduction of invasive s...

  20. Aquatic Plant Control Research Program. Use of the White Amur for Aquatic Plant Management.

    DTIC Science & Technology

    1984-08-01

    on the fate of the fish growth rates , food preferences, repro- through time-how their numbers, size, duction, and tolerances to various aquatic biomass...chemistry and native biota. While the within the water body, growth rates , and majority of the information for this report feeding preferences. A computer...temperate Amur Basin of the to two to three times the body weight under Soviet Union, the greatest growth rate of optimal conditions. This high rate

  1. Downstream effects of a hydroelectric reservoir on aquatic plant assemblages.

    PubMed

    Bernez, Ivan; Haury, Jacques; Ferreira, Maria Teresa

    2002-03-16

    Macrophytes were studied downstream of the Rophémel hydroelectric dam on the River Rance (Côtes d'Armor Department, western France) to assess the effects of hydroelectric functioning on river macrophyte communities. We studied ten representative sections of the hydro-peaking channel on five occasions in 1995 and 1996, on a 15-km stretch of river. Floristic surveys were carried out on sections 50 m in length, and genera of macroalgae, species of bryophyta, hydrophytes, and emergent rhizophytes were identified. For the aquatic bryophytes and spermatophytes section of our study, we compared our results with 19th century floristic surveys, before the dam was built. During the vegetative growth period, the hydro-peaking frequency was low. The plant richness was highest near the dam. The macrophyte communities were highly modified according to the distance to the dam. The frequency and magnitude of hydro-peaking was related to the aquatic macrophyte richness in an Intermediate Disturbance Hypothesis position. However, the results of the eco-historical comparison with 19th century floristic surveys point to the original nature of the flora found at the site. Some floral patterns, seen during both periods and at an interval of 133 years, were indicative of the ubiquity of the aquatic flora and of the plants" adaptability. This demonstrates the importance of taking river basin history into account in such biological surveys.

  2. Effect of lead and cadmium on aquatic plant Hydrilla verticillata.

    PubMed

    Singh, Alka; Kumar, Chandra Shekhar; Agarwal, Abha

    2013-11-01

    Absorption of different concentrations of Lead (Pb) and Cadmium (Cd) by aquatic plant Hydrilla vertcillato was measured during winter season for two different durations i.e. 3 days and 7 days. Effect of Pb and Cd was evaluated by analyzing various parameters such as biomass, total chlorophyll, carotenoid, protein, nitrate reductase activity, SOD (super oxide dismutase) and heavy metal uptake. Increase in biomass, total chlorophyll, protein and nitrate reductase activity was noticed at lower concentration of both metals whereas at higher metal concentrations of Pb and Cd, decrease in these parameters was observed i.e. it was concentration and duration dependent. Increase in carotenoid and SOD levels at high concentration of Pb and Cd indicated its ability of stress tolerance. Accumulation of Pb by test plant was found to be more than Cd at low concentration. Higher concentration of Cd and Pb caused toxicity which resulted in reduced plant growth and physiological activities.

  3. Biomechanical responses of aquatic plants to aerial conditions.

    PubMed

    Hamann, Elena; Puijalon, Sara

    2013-12-01

    Wetlands are impacted by changes in hydrological regimes that can lead to periods of low water levels. During these periods, aquatic plants experience a drastic change in the mechanical conditions that they encounter, from low gravitational and tensile hydrodynamic forces when exposed to flow under aquatic conditions, to high gravitational and bending forces under terrestrial conditions. The objective of this study was to test the capacity of aquatic plants to produce self-supporting growth forms when growing under aerial conditions by assessing their resistance to terrestrial mechanical conditions and the associated morpho-anatomical changes. Plastic responses to aerial conditions were assessed by sampling Berula erecta, Hippuris vulgaris, Juncus articulatus, Lythrum salicaria, Mentha aquatica, Myosotis scorpioides, Nuphar lutea and Sparganium emersum under submerged and emergent conditions. The cross-sectional area and dry matter content (DMC) were measured in the plant organs that bear the mechanical forces, and their biomechanical properties in tension and bending were assessed. All of the species except for two had significantly higher stiffness in bending and thus an increased resistance to terrestrial mechanical conditions when growing under emergent conditions. This response was determined either by an increased allocation to strengthening tissues and thus a higher DMC, or by an increased cross-sectional area. These morpho-anatomical changes also resulted in increased strength and stiffness in tension. The capacity of the studied species to colonize this fluctuating environment can be accounted for by a high degree of phenotypic plasticity in response to emersion. Further investigation is however needed to disentangle the finer mechanisms behind these responses (e.g. allometric relations, tissue make-up), their costs and adaptive value.

  4. Biomechanical responses of aquatic plants to aerial conditions

    PubMed Central

    Hamann, Elena; Puijalon, Sara

    2013-01-01

    Background and Aims Wetlands are impacted by changes in hydrological regimes that can lead to periods of low water levels. During these periods, aquatic plants experience a drastic change in the mechanical conditions that they encounter, from low gravitational and tensile hydrodynamic forces when exposed to flow under aquatic conditions, to high gravitational and bending forces under terrestrial conditions. The objective of this study was to test the capacity of aquatic plants to produce self-supporting growth forms when growing under aerial conditions by assessing their resistance to terrestrial mechanical conditions and the associated morpho-anatomical changes. Methods Plastic responses to aerial conditions were assessed by sampling Berula erecta, Hippuris vulgaris, Juncus articulatus, Lythrum salicaria, Mentha aquatica, Myosotis scorpioides, Nuphar lutea and Sparganium emersum under submerged and emergent conditions. The cross-sectional area and dry matter content (DMC) were measured in the plant organs that bear the mechanical forces, and their biomechanical properties in tension and bending were assessed. Key Results All of the species except for two had significantly higher stiffness in bending and thus an increased resistance to terrestrial mechanical conditions when growing under emergent conditions. This response was determined either by an increased allocation to strengthening tissues and thus a higher DMC, or by an increased cross-sectional area. These morpho-anatomical changes also resulted in increased strength and stiffness in tension. Conclusions The capacity of the studied species to colonize this fluctuating environment can be accounted for by a high degree of phenotypic plasticity in response to emersion. Further investigation is however needed to disentangle the finer mechanisms behind these responses (e.g. allometric relations, tissue make-up), their costs and adaptive value. PMID:24187030

  5. Geometrical relationships specifying the phyllotactic pattern of aquatic plants.

    PubMed

    Kelly, Wanda J; Cooke, Todd J

    2003-08-01

    The complete range of various phyllotaxes exemplified in aquatic plants provide an opportunity to characterize the fundamental geometrical relationships operating in leaf patterning. A new polar-coordinate model was used to characterize the correlation between the shapes of shoot meristems and the arrangements of young leaf primordia arising on those meristems. In aquatic plants, the primary geometrical relationship specifying spiral vs. whorled phyllotaxis is primordial position: primordia arising on the apical dome (as defined by displacement angles θ ≤ 90° during maximal phase) are often positioned in spiral patterns, whereas primordia arising on the subtending axis (as defined by displacement angles of θ ≥ 90° during maximal phase) are arranged in whorled patterns. A secondary geometrical relationship derived from the literature shows an inverse correlation between the primordial size : available space ratio and the magnitude of the Fibonacci numbers in spiral phyllotaxis or the number of leaves per whorl in whorled phyllotaxis. The data available for terrestrial plants suggest that their phyllotactic patterning may also be specified by these same geometrical relationships. Major exceptions to these correlations are attributable to persistent embryonic patterning, leaflike structures arising from stipules, congenital splitting of young primordia, and/or non-uniform elongating of internodes. The geometrical analysis described in this paper provides the morphological context for interpreting the phenotypes of phyllotaxis mutants and for constructing realistic models of the underlying mechanisms responsible for generating phyllotactic patterns.

  6. The ultrafast valve of an aquatic carnivorous plant

    NASA Astrophysics Data System (ADS)

    Marmottant, Philippe; Vincent, Olivier; Joyeux, Marc; Quilliet, Catherine; Poppinga, Simon; Weisskopf, Carmen; Masselter, Tom; Speck, Thomas

    2010-11-01

    Aquatic carnivorous bladderworts (Utricularia spp.) are plants that catch prey animals with suction traps. Here we present an experimental study with high speed video analyses of the extremely fast trapping movements, and show that suction is performed in less than a millisecond, much faster than previously thought. We reveal how the convex door morphology is optimized for a fast opening and closure, which we confirm by numerical simulations: the trapdoor is an elastic valve that buckles inside (entailing rapid opening) and then unbuckles (entailing rapid closure). These precise and reproducible motions are coupled with a strong suction swirl causing accelerations of up to 600 g, and leaving little escape chances for prey animals.

  7. Arsenic and mercury bioaccumulation in the aquatic plant, Vallisneria neotropicalis.

    PubMed

    Lafabrie, C; Major, K M; Major, C S; Cebrián, J

    2011-03-01

    Arsenic (As) and mercury (Hg) are among the most toxic metals/metalloids. The overall goal of this study was to investigate the bioaccumulation of these trace elements in Vallisneria neotropicalis, a key trophic species in aquatic environments. For this purpose, As and Hg concentrations were determined in sediments and natural populations of V. neotropicalis in sub-estuaries of Mobile Bay (Alabama, USA), differing with respect to past and present anthropogenic impact. Analyses indicate that the Fish River is the most contaminated among the sub-estuaries investigated; levels of As found in Fish River sediments fall within a range that could potentially cause adverse effects in biota. Sediment As concentrations were only moderately correlated with those in V. neotropicalis; no correlation was found between sediment and plant Hg levels. However, several parameters could have masked such potential relationships (e.g., differences in sediment characteristics and "biological dilution" phenomena). Results presented herein highlight the numerous parameters that can influence metal/metalloids accumulation in aquatic plants as well as species-specific responses to trace element contamination. Finally, this study underscores the need for further investigation into contaminant bioaccumulation in ecologically and economically important coastal environments.

  8. Remote sensing analysis of Lake Livingston aquatic plants

    NASA Technical Reports Server (NTRS)

    Benton, A. R., Jr.; Newman, R. M.

    1976-01-01

    Results obtained during 1975 to monitor the growth of aquatic plants in the Lake Livingston area, using remote sensing photographic imagery, were described. Sequential total coverage was provided of the Jungle and White Rock Creek, plus coverage of smaller areas of localized infestation downlake, including Brushy Creek, KOA Kampground Marina, Penwaugh Slough, Memorial Point Marina, the Beacon Bay marinas and Pine Island. The imagery was generally good, photographic exposure being increased as the season progressed in order to obtain better pictures of the submerged vegetation. Some very significant differences in growth patterns, species interaction, and species dominance were observed when compared to 1974. Observation of the following plants was discussed: water hyacinth, hydrilla, coontail, potamageton. In general, the level of infestation was lower in 1975 than in 1974, due to the combined effect of more systematic application of herbicides and harsher intervening winter weather conditions.

  9. Laboratory flume studies of microflow environments of aquatic plants

    NASA Astrophysics Data System (ADS)

    Shi, Z.; Hughes, J. M. R.

    2002-11-01

    The microflow environments of aquatic plants with reference to Myriophyllum and Hydrilla are simulated in a laboratory flume. A Nix Streamflow microflow meter was used to measure the mean velocity profiles of flow at different densities of plants, flow ranges and measurement positions. Each mean velocity profile consists of three hydrodynamic regimes (i.e. within-canopy zone, above-canopy zone and a transitional zone between them), which indicate the presence of two benthic boundary layers (internal and external ones). Out of 38 measured mean velocity profiles, most do not fit a logarithmic relationship. The following hydrodynamic parameters are used in characterizing the flow regimes: local shear velocity (u*), roughness length (zo), canopy roughness Reynolds number (Re*), bed shear stress (o) and laminar sublayer ().

  10. Aquatic Plant/microbial Filters for Treating Septic Tank Effluent

    NASA Technical Reports Server (NTRS)

    Wolverton, B. C.

    1988-01-01

    The use of natural biological processes for treating many types of wastewater have been developed by NASA at the John C. Stennis Space Center, NSTL, Mississippi, during the past 15 years. The simplest form of this technology involves the use of aquatic plant/marsh filters for treatment of septic tank effluent. Septic tank effluent from single home units can be treated to advanced secondary levels and beyond by using a 37.2 sq m (400 sq ft) surface area washed gravel filter. This filter is generally 0.3 m (1 ft) deep with a surface cover of approximately 0.15 m (6 in.) of gravel. The plants in this filter are usually aesthetic or ornamental such as calla lily (Zantedeschia aethiopica), canna lily (Canna flaccida), elephant ear (Colocasia esculenta), and water iris (Iris pseudacorus).

  11. Aquatic plants exposed to pharmaceuticals: effects and risks.

    PubMed

    Brain, Richard A; Hanson, Mark L; Solomon, Keith R; Brooks, Bryan W

    2008-01-01

    Pharmaceuticals are biologically active, ubiquitous, low-level contaminants that are continuously introduced into the environment from both human and veterinary applications at volumes comparable to total pesticide loadings. Recent analytical advances have made possible the detection of a number of these compounds in environmental samples, raising concerns over potential nontarget effects to aquatic organisms, especially given the highly specific biologically active nature of these compounds. These concerns become paramount when the evolutionary conservation of metabolic pathways and receptors is taken into consideration, particularly in the case of aquatic plants, where a great deal of homology is displayed between the chloroplast and bacteria, as well as between other metabolic pathways across multiple phyla of biological organization. Common receptors have been identified in plants for a number of antibiotics affecting chloroplast replication (fluoroquinolones) transcription and translation (tetracyclines macrolides, lincosamides, P-aminoglycosides, and pleuromutilins), metabolic pathways such as folate biosynthesis (sulfonamides) and fatty acid biosynthesis (triclosan), as well as other classes of pharmaceuticals that affect sterol biosynthesis (statin-type blood lipid regulators). Toxicological investigations into the potency of these compounds indicates susceptibility across multiple plant species, although sensitivity to these compounds varies widely between blue-green algae, green algae, and higher plants in a rather inconsistent manner, except that Cyanobacteria are largely the most sensitive to antibiotic compounds. This differential sensitivity is likely dependent on differences in metabolic potential as well as uptake kinetics, which has been demonstrated for a number of compounds from another class of biologically active compounds, pesticides. The demonstration of conserved receptors and pathways in plants is not surprising, although it has been

  12. Biogeochemical features of aquatic plants in the Selenga River delta

    NASA Astrophysics Data System (ADS)

    Shinkareva, Galina; Lychagin, Mikhail

    2014-05-01

    The Selenga River system provides more than a half of the Lake Baikal total inflow. The river collects a significant amount of pollutants (e.g. heavy metals) from the whole basin. These substances are partially deposited within the Selenga delta, and partially are transported further to the lake. A generous amount of aquatic plants grow in the delta area according to its favorable conditions. This vegetation works as a specific biofilter. It accumulates suspended particles and sorbs some heavy metals from the water. The study aimed to reveal the species of macrophytes which could be mostly important for biomonitoring according to their chemical composition. The field campaign took place in the Selenga River delta in July-August of 2011 (high water period) and in June of 2012 (low water period). 14 species of aquatic plants were collected: water starwort Callitriche hermaphroditica, small yellow pond lily Nuphar pumila, pondweeds Potamogeton crispus, P. pectinatus, P. friesii, broadleaf cattail Typha latifolia, hornwort or coontail Ceratophyllum demersum, arrowhead Sagittaria natans, flowering rush (or grass rush) Butomus umbellatus, reed Phragmites australis, parrot's feather Myriophyllum spicatum, the common mare's tail Hippuris vulgaris, Batrachium trichophyllum, canadian waterweed Elodea canadensis. The samples were dried, grinded up and digested in a mixture of HNO3 and H2O2. The chemical composition of the plant material was defined using ICP-MS and ICP-AES methods. Concentrations of Fe, Mn, Cr, Ni, Cu, B, Zn, V, Co, As, Mo, Pb, and U were considered. The study revealed that Potamogeton pectinatus and Myriophyllum spicatum concentrate elements during both high and low water periods. Conversely the Butomus umbellatus and Phragmites australis contain small amount of heavy metals. The reed as true grasses usually accumulates fewer amounts of elements than other macrophytes. To compare biogeochemical specialization of different species we suggest to use

  13. Aquatic Plant Control Research Program: Effects of Water Chemistry on Aquatic Plants: Interactive Effects of Inorganic Carbon and Nitrogen on Biomass Production and Plant Nutrition

    DTIC Science & Technology

    1990-07-01

    Myriophyllum was more affected by (Continued) 20. DISTRIBUTION /AVAILABILITY OF ABSTRACT 21 ABSTRACT SECURITY CLASSIFICATION qUNCLASSIFIED/UNLIMITED 0...Continued). Aquatic plants Hydrilla Nutrient uptake Carbon limitation Myriophyllum Submersed macrophytes Egeria Nutrient limitation Water chemistry 19... Myriophyllum , by virtue of its relatively greater root production, was more effective at N acquisition, and thus produced the most biomass under

  14. Aquatic Plant Control Research Program: The Rhizosphere Microbiology of Rooted Aquatic Plants.

    DTIC Science & Technology

    1988-04-01

    processes in terrestrial and marine plants. Nature and Properties of the Rhizosphere Sediment environment 4. A great deal of research has been...investigators have studied nitrogen fixation in Halodule wrightii in the marine environment. Smith and Hayasaka (1982a) examined nitrogenase activity associated...few studies on sulfur cycling in the rhizosphere, despite the plethora of information on sulfur biogeochemistry in both fresh- water and marine

  15. Differentiating aquatic plant communities in a eutrophic river using hyperspectral and multispectral remote sensing

    USGS Publications Warehouse

    Tian, Y.Q.; Yu, Q.; Zimmerman, M.J.; Flint, S.; Waldron, M.C.

    2010-01-01

    This study evaluates the efficacy of remote sensing technology to monitor species composition, areal extent and density of aquatic plants (macrophytes and filamentous algae) in impoundments where their presence may violate water-quality standards. Multispectral satellite (IKONOS) images and more than 500 in situ hyperspectral samples were acquired to map aquatic plant distributions. By analyzing field measurements, we created a library of hyperspectral signatures for a variety of aquatic plant species, associations and densities. We also used three vegetation indices. Normalized Difference Vegetation Index (NDVI), near-infrared (NIR)-Green Angle Index (NGAI) and normalized water absorption depth (DH), at wavelengths 554, 680, 820 and 977 nm to differentiate among aquatic plant species composition, areal density and thickness in cases where hyperspectral analysis yielded potentially ambiguous interpretations. We compared the NDVI derived from IKONOS imagery with the in situ, hyperspectral-derived NDVI. The IKONOS-based images were also compared to data obtained through routine visual observations. Our results confirmed that aquatic species composition alters spectral signatures and affects the accuracy of remote sensing of aquatic plant density. The results also demonstrated that the NGAI has apparent advantages in estimating density over the NDVI and the DH. In the feature space of the three indices, 3D scatter plot analysis revealed that hyperspectral data can differentiate several aquatic plant associations. High-resolution multispectral imagery provided useful information to distinguish among biophysical aquatic plant characteristics. Classification analysis indicated that using satellite imagery to assess Lemna coverage yielded an overall agreement of 79% with visual observations and >90% agreement for the densest aquatic plant coverages. Interpretation of biophysical parameters derived from high-resolution satellite or airborne imagery should prove to be a

  16. Triclosan removal in wetlands constructed with different aquatic plants.

    PubMed

    Liu, Jianing; Wang, Jingmin; Zhao, Congcong; Hay, Anthony G; Xie, Huijun; Zhan, Jian

    2015-10-22

    Triclosan (TCS) is widely used in consumer products as an antimicrobial agent. Constructed wetlands have the potential for TCS removal, but knowledge about the relative importance of sediment, plants, and microbes is limited. TCS removal performance was investigated in well-operated constructed wetlands planted with three different types of aquatic plants: emergent Cattail (C-T), submerged Hornwort (H-T), and floating Lemnaminor (L-T). Results showed that the TCS removal efficiencies from water were all greater than 97 %. Maximal TCS adsorption to sediment in the C-T wetland (13.8 ± 0.6 ng/g) was significantly lower than in the H-T wetland (21.0 ± 0.3 ng/g) or the L-T wetland (21.4 ± 0.6 ng/g). The maximal TCS concentrations in plants were 5.7 ± 0.2 and 7.2 ± 0.5 μg/g for H-T and L-T, respectively, and it was below the minimal detection limit (MDL) in C-T. Deep 16S rRNA gene sequencing results revealed that C-T wetland had the highest community richness and diversity. Some bacteria, like beta-Proteobacteria, gamma-Proteobacteria, and Bacteroidetes were detected and might have significant correlations with TCS degradation. Overall, with regard to soils, plants, and microorganism, accumulation in sediment and plants in H-T and L-T was high, while in C-T biodegradation likely played an important role.

  17. 33 CFR Appendix B to Part 273 - Information Requirements for Aquatic Plant Control Program Reports

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 33 Navigation and Navigable Waters 3 2012-07-01 2012-07-01 false Information Requirements for Aquatic Plant Control Program Reports B Appendix B to Part 273 Navigation and Navigable Waters CORPS OF ENGINEERS, DEPARTMENT OF THE ARMY, DEPARTMENT OF DEFENSE AQUATIC PLANT CONTROL Pt. 273, App. B Appendix B...

  18. An updated checklist of aquatic plants of Myanmar and Thailand

    PubMed Central

    2014-01-01

    Abstract The flora of Tropical Asia is among the richest in the world, yet the actual diversity is estimated to be much higher than previously reported. Myanmar and Thailand are adjacent countries that together occupy more than the half the area of continental Tropical Asia. This geographic area is diverse ecologically, ranging from cool-temperate to tropical climates, and includes from coast, rainforests and high mountain elevations. An updated checklist of aquatic plants, which includes 78 species in 44 genera from 24 families, are presented based on floristic works. This number includes seven species, that have never been listed in the previous floras and checklists. The species (excluding non-indigenous taxa) were categorized by five geographic groups with the exception of to reflect the rich diversity of the countries' floras. PMID:24723783

  19. Plant Growth Regulators as Potential Tools in Aquatic Plant Management: Efficacy and Persistence in Small-Scale Tests

    DTIC Science & Technology

    1994-01-01

    Growth Regulators as Potential Tools in Aquatic Plant Management: Efficacy and Persistence in Small-Scale Tests by Carole A. Lembi, Tara Chand-Goyal...Research Program January 1994 Plant Growth Regulators as Potential Tools in Aquatic Plant Management: Efficacy and Persistence in Small-Scale Tests by...ulal D Lemb, Car GEMECH111ACA IXmMN ~~rO POl miA1N 90MT •Y m In DMIMDTLemi PUBLIC AFAR.OFC Plant growth regulators as potential tools in aquatic plant

  20. Remote Sensing and Modeling for Improving Operational Aquatic Plant Management

    NASA Technical Reports Server (NTRS)

    Bubenheim, Dave

    2016-01-01

    The California Sacramento-San Joaquin River Delta is the hub for California’s water supply, conveying water from Northern to Southern California agriculture and communities while supporting important ecosystem services, agriculture, and communities in the Delta. Changes in climate, long-term drought, water quality changes, and expansion of invasive aquatic plants threatens ecosystems, impedes ecosystem restoration, and is economically, environmentally, and sociologically detrimental to the San Francisco Bay/California Delta complex. NASA Ames Research Center and the USDA-ARS partnered with the State of California and local governments to develop science-based, adaptive-management strategies for the Sacramento-San Joaquin Delta. The project combines science, operations, and economics related to integrated management scenarios for aquatic weeds to help land and waterway managers make science-informed decisions regarding management and outcomes. The team provides a comprehensive understanding of agricultural and urban land use in the Delta and the major water sheds (San Joaquin/Sacramento) supplying the Delta and interaction with drought and climate impacts on the environment, water quality, and weed growth. The team recommends conservation and modified land-use practices and aids local Delta stakeholders in developing management strategies. New remote sensing tools have been developed to enhance ability to assess conditions, inform decision support tools, and monitor management practices. Science gaps in understanding how native and invasive plants respond to altered environmental conditions are being filled and provide critical biological response parameters for Delta-SWAT simulation modeling. Operational agencies such as the California Department of Boating and Waterways provide testing and act as initial adopter of decision support tools. Methods developed by the project can become routine land and water management tools in complex river delta systems.

  1. Study on MMW radiation characteristics and imaging of aquatic plants for environmental application

    NASA Astrophysics Data System (ADS)

    Zhou, Luyan; Zhang, Guangfeng; Liu, Jing

    2017-02-01

    Working all-day and all-weather, the passive millimeter wave radiometer is widely used in remote sensing, guidance and other fields. In order to solve the increasingly serious problem of water pollution, especially the pollution caused by the rapidly breed of the aquatic plants, a simple and effective method to monitor the water environment is proposed. Aquatic plants can be distinguished through millimeter wave system, as they have high bright temperature compared to Water. The 8mm radiometer is used to measure the radiation characteristics of aquatic plants and image. The simulation results and radiation imaging experiments prove the feasibility and effectively of monitoring aquatic plants by millimeter wave radiometer. This study will contribute to monitoring the aquatic plants growth and decreasing the pollution.

  2. Environmental Factors Affecting Aquatic Plant Growth Potential in Marinuka Lake, Wisconsin

    DTIC Science & Technology

    2008-12-01

    ERDC/TN APCRP-EA-20 December 2008 Environmental Factors Affecting Aquatic Plant Growth Potential in Marinuka Lake, Wisconsin by William F. James...2008 Experimental evaluation of plant growth potential on Marinuka Lake sediments. Aquatic sediments were collected from Marinuka Lake and Eau Galle...Ten replicates for each sediment type (one plant per container) were incubated in a large outdoor facility consisting of plant growth tanks (4 ft

  3. Aquatic adventitious root development in partially and completely submerged wetland plants Cotula coronopifolia and Meionectes brownii.

    PubMed

    Rich, Sarah Meghan; Ludwig, Martha; Colmer, Timothy David

    2012-07-01

    A common response of wetland plants to flooding is the formation of aquatic adventitious roots. Observations of aquatic root growth are widespread; however, controlled studies of aquatic roots of terrestrial herbaceous species are scarce. Submergence tolerance and aquatic root growth and physiology were evaluated in two herbaceous, perennial wetland species Cotula coronopifolia and Meionectes brownii. Plants were raised in large pots with 'sediment' roots in nutrient solution and then placed into individual tanks and shoots were left in air or submerged (completely or partially). The effects on growth of aquatic root removal, and of light availability to submerged plant organs, were evaluated. Responses of aquatic root porosity, chlorophyll and underwater photosynthesis, were studied. Both species tolerated 4 weeks of complete or partial submergence. Extensive, photosynthetically active, aquatic adventitious roots grew from submerged stems and contributed up to 90 % of the total root dry mass. When aquatic roots were pruned, completely submerged plants grew less and had lower stem and leaf chlorophyll a, as compared with controls with intact roots. Roots exposed to the lowest PAR (daily mean 4.7 ± 2.4 µmol m(-2) s(-1)) under water contained less chlorophyll, but there was no difference in aquatic root biomass after 4 weeks, regardless of light availability in the water column (high PAR was available to all emergent shoots). Both M. brownii and C. coronopifolia responded to submergence with growth of aquatic adventitious roots, which essentially replaced the existing sediment root system. These aquatic roots contained chlorophyll and were photosynthetically active. Removal of aquatic roots had negative effects on plant growth during partial and complete submergence.

  4. Aquatic adventitious root development in partially and completely submerged wetland plants Cotula coronopifolia and Meionectes brownii

    PubMed Central

    Rich, Sarah Meghan; Ludwig, Martha; Colmer, Timothy David

    2012-01-01

    Background and Aims A common response of wetland plants to flooding is the formation of aquatic adventitious roots. Observations of aquatic root growth are widespread; however, controlled studies of aquatic roots of terrestrial herbaceous species are scarce. Submergence tolerance and aquatic root growth and physiology were evaluated in two herbaceous, perennial wetland species Cotula coronopifolia and Meionectes brownii. Methods Plants were raised in large pots with ‘sediment’ roots in nutrient solution and then placed into individual tanks and shoots were left in air or submerged (completely or partially). The effects on growth of aquatic root removal, and of light availability to submerged plant organs, were evaluated. Responses of aquatic root porosity, chlorophyll and underwater photosynthesis, were studied. Key Results Both species tolerated 4 weeks of complete or partial submergence. Extensive, photosynthetically active, aquatic adventitious roots grew from submerged stems and contributed up to 90 % of the total root dry mass. When aquatic roots were pruned, completely submerged plants grew less and had lower stem and leaf chlorophyll a, as compared with controls with intact roots. Roots exposed to the lowest PAR (daily mean 4·7 ± 2·4 µmol m−2 s−1) under water contained less chlorophyll, but there was no difference in aquatic root biomass after 4 weeks, regardless of light availability in the water column (high PAR was available to all emergent shoots). Conclusions Both M. brownii and C. coronopifolia responded to submergence with growth of aquatic adventitious roots, which essentially replaced the existing sediment root system. These aquatic roots contained chlorophyll and were photosynthetically active. Removal of aquatic roots had negative effects on plant growth during partial and complete submergence. PMID:22419759

  5. Remote sensing of aquatic plants. [New York, Florida, Texas, Louisiana, Mississippi, South Carolina

    NASA Technical Reports Server (NTRS)

    Long, K. S.; Link, L. E., Jr.

    1977-01-01

    Various sensors were tested in terms of their ability to detect and discriminate among noxious aquatic macrophytes. A survey of researchers currently studying the problem and a brief summary of their work is included. Results indicated that the sensor types best suited to assessment of the aquatic environment are color, color infrared, and black-and-white infrared film, which furnish consistently high contrasts between aquatic plants and their surroundings.

  6. Ash characteristics and plant nutrients in some aquatic biomasses

    NASA Astrophysics Data System (ADS)

    Masto, Reginald; Pandit, Ankita; George, Joshy; Mukhopadhyay, Sangeeta; Selvi, Vetrivel; Ram, Lal

    2016-04-01

    Aquatic biomasses are explored as potential fuel source for direct combustion because of their faster growth and no land requirement. The energy density and the ash characteristics of the aquatic biomasses are to be evaluated for their suitability for energy extraction. In the study, four aquatic plant samples namely Eichornia crassipes, Hydrilla verticilleta, Lemna minor, Spirogyra spp were collected from a pond in Digwadih Campus of Central Institute of Mining and Fuel Research, Dhanbad. The biomasses were air dried, powdered and ashed at different temperatures. Volatile C was relatively lower in Spirogyra and Hydrilla (53 %) than Eichornia (62.6 %) or Lemna (59.7 %), whereas fixed C was higher for Eichornia and Lemna (about 10 %) and lower for Hydrilla (1 %). Ultimate analysis showed that the carbon content was in the order Eichornia > Lemna > Spirogyra > Hydrilla. The IR spectra of each raw biomass is compared to their respective ashes obtained at different temperatures (500-900°C). With increase in ashing temperature from 500-900°C there is gradual breakdown of the cellulosic structure hence, peaks around 2900-2800cm-1 caused by aliphatic C-H vibration tends to disappear slowly in ash. More number of peaks appears at lower wavenumbers in ashes of all the biomass samples indicating towards increased percentage of inorganic ion species. Considerable enrichment of SiO2 is validated with prominent peaks at 1100-900 cm-1 in all the ashes. Lemna and Spirogyra has a similar ash composition (Si > Al > Ca > K), whereas, Ca was higher in Hydrilla (Si > Ca > K > Al). Eichornia (Si > K > Ca > Al) has higher K and Ca than Al. SiO2 and Al2O3 were higher in Spirogyra, while SiO2 and CaO in Eichornia and Hydrilla. K first increased from 500-700/800⁰C, and then decreased from 800-900⁰C. Cl is lost slowly in ash from 500-700/800⁰C and then by a drastic reduction from 800-900⁰C. S is enhanced in ash at all temperatures although the change is quite small. Most of the Cl

  7. Pathways of introduction of the invasive aquatic plant Cabomba caroliniana

    PubMed Central

    McCracken, Andrée; Bainard, Jillian D; Miller, Michelle C; Husband, Brian C

    2013-01-01

    The pathway and frequency of species' introductions can affect the extent, impact, and management of biological invasions. Here, we examine the pathway of introduction of the aquatic plant Cabomba caroliniana (fanwort) into Canada and the northern United States using plastid DNA sequence (intergenic spacers atpF-atpH, trnH-psbA, and trnL-trnF) and DNA content analyses. We test the hypothesis that the spread of fanwort is a result of commercial trade by comparing a Canadian population (Kasshabog Lake, ON) to native populations from southern U.S., introduced populations in northern U.S., and plants from commercial retailers. Thirteen plastid haplotypes were identified throughout North America, including one dominant haplotype, which was present in all C. caroliniana populations. Several rare haplotypes were used to infer shared colonization history. In particular, the Canadian population shared two rare alleles with a population from Massachusetts, suggesting range expansion of C. caroliniana from the northern U.S. However, the possibility of a commercial introduction cannot be excluded, as common alleles were shared between the Canadian population and both commercial and southern U.S. sources. Variation in C. caroliniana genome size was bimodal and populations were classified into “high” and “low” categories. The Canadian population had DNA contents similar to several northern U.S. populations (low DNA content). This may provide additional support for range expansion from these introduced populations rather than from commercial sources or populations in the southern U.S., which had high DNA content. PMID:23789056

  8. Biomass or growth rate endpoint for algae and aquatic plants: relevance for the aquatic risk assessment of herbicides.

    PubMed

    Bergtold, Matthias; Dohmen, Gerhard Peter

    2011-04-01

    Ecotoxicological studies with algae and aquatic plants are essential parts of the aquatic risk assessment for crop protection products (CPP). Growth rate is used as a response variable and in addition the effects on biomass and/or yield (in the following biomass) can be measured. The parameter biomass generally provides a lower numerical value compared with the growth rate for systematic and mathematical reasons. Therefore, some regulators prefer to use the EbC50 value (i.e., the concentration at which 50% reduction of biomass is observed) rather than ErC50 (the concentration at which a 50% inhibition of growth rate is observed) as the endpoint for ecotoxicological risk assessment. However, the parameter growth rate is scientifically more appropriate and robust against deviations in test conditions, permitting better interpretation of, and comparison between, studies. The aim of the present work is to evaluate the growth rate and biomass parameters with regard to their protectiveness and suitability for environmental risk assessment of CPP. It has been shown for a number of herbicides that the use of the EC50 value (without distinction between growth rate and biomass endpoints) from laboratory studies in combination with an assessment factor of 10 is sufficiently protective for aquatic plants (except for the herbicide 2,4-D). In this paper we evaluated EbC50 and ErC50 values separately. Data on 19 different herbicides were compiled from the literature or GLP reports. The EbC50 and ErC50 values obtained in laboratory studies were compared with effect concentrations in ecosystem studies (mainly mesocosm). This comparison of laboratory and field data shows that the overall aquatic risk assessment using ErC50 values in combination with the currently applied assessment factor of 10 is sufficient to exclude significant risk to aquatic plants in the environment. Copyright © 2010 SETAC.

  9. Comparative Study on Vegetative and Reproductive Development between Weedy Rice Morphotypes and Commercial Rice Varieties in Perak, Malaysia

    PubMed Central

    Ahmed, Quazi Nasim; Hussain, PMD Zainudin; Othman, Ahmad Sofiman

    2012-01-01

    This study was conducted to examine the variabilities in the chronology of vegetative and reproductive development of weedy rice (Oryza spp.) in comparison with commercial varieties. Data at different growth stages of 14 weedy rice morphotypes and 4 commercial rice varieties were recorded and analysed. Plant height of all weedy rice morphotypes were observed to be significantly higher compared to the commercial varieties at every growth stages; increase in height was between 10–37 cm for weedy rice morphotype, for every 2 weeks. Initial tillering ability at 14 days after planting (DAP) was higher in weedy morphotypes, however all the commercial rice varieties produced significantly higher number of tillers throughout the rest of the vegetative phases. Correlation between plant height and tiller number detected that taller plants produce fewer tillers than shorter plants. Higher leaf area index (LAI) of all weedy morphotypes except PWR01 at early growth stages indicated the vigorous growth of the morphotypes. Weedy rice morphotypes showed a wide range of anthesis and maturity duration. Accessions from the same weedy rice morphotypes were more heterogeneous in the flowering, anthesis and maturity period than the commercial varieties. These traits enables identification of weedy rice morphotypes at their different growth stages in the field. PMID:24575230

  10. UPTAKE AND PHYTOTRANSFORMATION OF ORGANOPHOSPHORUS PESTICIDES BY AXENICALLY CULTIVATED AQUATIC PLANTS

    EPA Science Inventory

    The uptake and phytotransformation of organophosphorus (OP) pesticides (malathion, demeton-S-methyl, and crufomate) was investigated in vitro using the axenically aquatic cultivated plants parrot feather (Myriophyllum aquaticum), duckweed (Spirodela oligorrhiza L.), and elodea (E...

  11. Comparison of four aquatic plant treatment systems for nutrient removal from eutrophied water.

    PubMed

    Li, Jihua; Yang, Xiaoying; Wang, Zhengfang; Shan, Ying; Zheng, Zheng

    2015-03-01

    Nutrient removal behaviors of four aquatic plant treatment systems (Oenanthe javanica, Iris pseudacorus L., Canna lily, and Potamogeton crispus) were systematically examined and compared. The kinetics of nutrient uptake were conducted with the standard depletion method. All four aquatic species exhibited a strong preference of ammonium nitrogen (NH4(+)-N) over nitrate nitrogen (NO3(-)-N) and nitrite nitrogen (NO2(-)-N). Main pathways of nutrient removal in the aquatic plant treatment system were examined in details. It was estimated that direct assimilation by plants accounted for 28.2-34.5% of N reduction and 25.2-33.4% of P reduction while substrate absorption accounted for 7.2-25.5% of N reduction and 7.3-25.0% of P reduction. The activity of urease and phosphatase in the substrates could indicate the aquatic plant treatment system's capability for reducing TN and soluble P load.

  12. UPTAKE AND PHYTOTRANSFORMATION OF ORGANOPHOSPHORUS PESTICIDES BY AXENICALLY CULTIVATED AQUATIC PLANTS

    EPA Science Inventory

    The uptake and phytotransformation of organophosphorus (OP) pesticides (malathion, demeton-S-methyl, and crufomate) was investigated in vitro using the axenically aquatic cultivated plants parrot feather (Myriophyllum aquaticum), duckweed (Spirodela oligorrhiza L.), and elodea (E...

  13. Aquatic plant Azolla as the universal feedstock for biofuel production.

    PubMed

    Miranda, Ana F; Biswas, Bijoy; Ramkumar, Narasimhan; Singh, Rawel; Kumar, Jitendra; James, Anton; Roddick, Felicity; Lal, Banwari; Subudhi, Sanjukta; Bhaskar, Thallada; Mouradov, Aidyn

    2016-01-01

    The quest for sustainable production of renewable and cheap biofuels has triggered an intensive search for domestication of the next generation of bioenergy crops. Aquatic plants which can rapidly colonize wetlands are attracting attention because of their ability to grow in wastewaters and produce large amounts of biomass. Representatives of Azolla species are some of the fastest growing plants, producing substantial biomass when growing in contaminated water and natural ecosystems. Together with their evolutional symbiont, the cyanobacterium Anabaena azollae, Azolla biomass has a unique chemical composition accumulating in each leaf including three major types of bioenergy molecules: cellulose/hemicellulose, starch and lipids, resembling combinations of terrestrial bioenergy crops and microalgae. The growth of Azolla filiculoides in synthetic wastewater led up to 25, 69, 24 and 40 % reduction of NH4-N, NO3-N, PO4-P and selenium, respectively, after 5 days of treatment. This led to a 2.6-fold reduction in toxicity of the treated wastewater to shrimps, common inhabitants of wetlands. Two Azolla species, Azolla filiculoides and Azolla pinnata, were used as feedstock for the production of a range of functional hydrocarbons through hydrothermal liquefaction, bio-hydrogen and bio-ethanol. Given the high annual productivity of Azolla, hydrothermal liquefaction can lead to the theoretical production of 20.2 t/ha-year of bio-oil and 48 t/ha-year of bio-char. The ethanol production from Azolla filiculoides, 11.7 × 10(3) L/ha-year, is close to that from corn stover (13.3 × 10(3) L/ha-year), but higher than from miscanthus (2.3 × 10(3) L/ha-year) and woody plants, such as willow (0.3 × 10(3) L/ha-year) and poplar (1.3 × 10(3) L/ha-year). With a high C/N ratio, fermentation of Azolla biomass generates 2.2 mol/mol glucose/xylose of hydrogen, making this species a competitive feedstock for hydrogen production compared with other bioenergy crops. The

  14. Aquatic Plant Control Research Program. Feasibility of Relating Phenology and Carbohydrate Partitioning to Improve Aquatic Plant Control

    DTIC Science & Technology

    1988-07-01

    Journal of Botany 71:165-169. Getsinger, K. D. 1982. The life cycle and physiology of the submersed angiosperm Egeria densa Planch. in Lake Marion, South...community 4 of an acidic lake in Adirondack (New York, U.S.A.): A new depth record for aquatic angiosperms . Aquatic Botany 16:49-57. Smith, D. 1975. Forest

  15. Recognition of pyrrolizidine alkaloid esters in the invasive aquatic plant Gymnocoronis spilanthoides (Asteraceae)

    USDA-ARS?s Scientific Manuscript database

    Introduction – The freshwater aquatic plant Gymnocoronis spilanthoides (Senegal tea plant, jazmín del bañado, Falscher Wasserfreund) is an invasive plant in many countries. Behavioural observations of pyrrolizidine alkaloid-pharmacophagous butterflies suggested the presence of pyrrolizidine alkaloid...

  16. Mechanical Harvesting of Aquatic Plants. Report 3. Evaluation of the Limnos System.

    DTIC Science & Technology

    1984-05-01

    portions are characterized by hard- wood swamps and some marshlands. The target problem aquatic plant in this environment is the waterhyacinth ( Eichhornia ... crassipes (Hart.) Solms). In situ densities of this plant range from 40 to over 150 tons per acre. Distribution of the plant is predominately aligned

  17. Selenium detoxification by volatilization and precipitation in aquatic plants

    SciTech Connect

    Fan, T.W.M.; Higashi, R.M.

    1995-12-31

    The narrow margin of requirement and toxicity for selenium makes it a difficult pollution problem to solve. Selenium bioaccumulation has been a major threat to wildlife in California and is becoming a major concern in the San Francisco Bay/Estuaries. Despite the past efforts in Se nutrition, chemistry, and remediation, its toxicity and detoxification mechanism(s) in wildlife, particularly primary producers, is still unclear, due to a lack of understanding in Se biochemistry. This is becoming a critical issue in assessing Se risk and remediation. To address this gap, the authors have been characterizing Se speciation and its linkage to detoxification mechanism(s) of two indigenous aquatic plants, duckweed (Lemna minor) and a microphyte (Chlorella). Using GT-MS analysis, they found that Chlorella monocultures transformed Se oxyanions into volatile dimethylselenide and dimethyidiselenide and into insoluble So at extremely high Se (up to 750 ppm) concentrations. This alga did not accumulate selenomethionine which is among the most toxic forms of Se to wildlife. Dimethylsulfide was also volatilized, consistent with the hypothesis that dimethylsulfide/dimethylselenide emissions share a similar biochemical pathway. Se-treated Chlorella biomass released dimethylsulfide/dimethylselenide upon alkaline hydrolysis, suggesting the presence of dimethylsulfonium and dimethylselenonium propionates. Dimethylsulfoniumpropionate is known as an osmoprotectant in marine phytoplankton and as a major contributor to global biogenic dimethylsulfide emissions. Dimethylselenoniumpropionate has not been identified previously and may be a byproduct of dimethylsulfoniumpropionate synthesis. The unusual Se tolerance of Chlorella may be due to its ability to volatilize and precipitate Se. Such activities may be utilized for in situ Se bioremediation. Similar investigations with duckweed is underway.

  18. Comprehensive review on phytotechnology: Heavy metals removal by diverse aquatic plants species from wastewater.

    PubMed

    Rezania, Shahabaldin; Taib, Shazwin Mat; Md Din, Mohd Fadhil; Dahalan, Farrah Aini; Kamyab, Hesam

    2016-11-15

    Environmental pollution specifically water pollution is alarming both in the developed and developing countries. Heavy metal contamination of water resources is a critical issue which adversely affects humans, plants and animals. Phytoremediation is a cost-effective remediation technology which able to treat heavy metal polluted sites. This environmental friendly method has been successfully implemented in constructed wetland (CWs) which is able to restore the aquatic biosystem naturally. Nowadays, many aquatic plant species are being investigated to determine their potential and effectiveness for phytoremediation application, especially high growth rate plants i.e. macrophytes. Based on the findings, phytofiltration (rhizofiltration) is the sole method which defined as heavy metals removal from water by aquatic plants. Due to specific morphology and higher growth rate, free-floating plants were more efficient to uptake heavy metals in comparison with submerged and emergent plants. In this review, the potential of wide range of aquatic plant species with main focus on four well known species (hyper-accumulators): Pistia stratiotes, Eicchornia spp., Lemna spp. and Salvinia spp. was investigated. Moreover, we discussed about the history, methods and future prospects in phytoremediation of heavy metals by aquatic plants comprehensively. Copyright © 2016. Published by Elsevier B.V.

  19. [Development characteristics of aquatic plants in a constructed wetland for treating urban drinking water source at its initial operation stage].

    PubMed

    Zheng, Jun; Ma, Xin-Tang; Zhou, Lan; Zhou, Qing-Yuan; Wang, Zhong-Qiong; Wang, Wei-Dong; Yin, Cheng-Qing

    2011-08-01

    The development characteristics and improvement measures of aquatic plants were studied in Shijiuyang Constructed Wetland (SCW) at its initial operation stage. SCW was a large-scale wetland aiming to help relieve the source water pollution in Jiaxing City. A checklist of vascular plants in SCW was built, and species composition, life forms, biomass and association distributions were examined. Our objectives were to examine the diversity and community structure of aquatic plants in SCW at its initial operation stage, and to find out the possible hydrophyte improvement measures. The survey results showed that there were 49 vascular plant species belonging to 41 genera, 25 families in SCW, which greatly exceeded the artificially transplanted 13 species. The life forms of present aquatic plants in SCW were dominated by hygrophilous plants (20 species) and emerged plants (17 species), which accounted for 75.5% of the total number of aquatic plants. The aquatic plants transplanted artificially were dominated by emerged plants (accounted for 69.2%), while those naturally developed were predominated by hygrophilous plants (accounted for 47.2%). The horizontal distribution of aquatic plant community in SCW was mixed in the form of mosaics, which made up typical association complex. Except association Aeschynomene indica L., the dominant species of other associations were all those transplanted artificially. The naturally grown species scattered throughout the SCW and only occupied a small percentage. A marked difference was detected on the species and species richness of aquatic plants in different regions of SCW. Biomass of aquatic plant associations in SCW was 167.7 t. SCW has shown a trend of succession heading for quick increase of plant diversity at the primary operation stage. This trend provides a good material base for the future stable community of aquatic plants in SCW. According to the current status of aquatic plants, some suggestions were put forward on the

  20. Transfer of oxytetracycline from swine manure to three different aquatic plants: implications for human exposure.

    PubMed

    Boonsaner, Maliwan; Hawker, Darryl W

    2015-03-01

    Little is known regarding the potential for pharmaceuticals including antibiotics to be accumulated in edible aquatic plants and enter the human food chain. This work investigates the transfer of a widely used veterinary antibiotic, oxytetracycline (OTC), from swine manure to aquatic plants by firstly characterizing desorption from swine manure to water and fitting data to both nonlinear and linear isotherms. Bioconcentration of OTC from water was then quantified with aquatic plants of contrasting morphology and growth habit viz. watermeal (Wolffia globosa Hartog and Plas), cabomba (Cabomba caroliniana A. Gray) and water spinach (Ipomoea aquatica Forsk.). Watermeal and water spinach are widely consumed in Southeast Asia. The OTC desorption and bioconcentration data were used to provide the first quantitative estimates of human exposure to OTC from a manure-water-aquatic plant route. Results show that under certain conditions (plants growing for 15d in undiluted swine manure effluent (2% w/v solids) and an initial OTC swine manure concentration of 43mgkg(-1) (dry weight)), this pathway could provide a significant fraction (>48%) of the acceptable daily intake (ADI) for OTC. While effluent dilution, lower OTC manure concentrations and not all plant material consumed being contaminated would be expected to diminish the proportion of the ADI accumulated, uptake from aquatic plants should not be ignored when determining human exposure to antibiotics such as OTC. Copyright © 2014 Elsevier Ltd. All rights reserved.

  1. Treatment with aquatic plants by a Bagdi tribal healer of Rajbari District, Bangladesh

    PubMed Central

    Mukti, Mohsina; Rahmatullah, Mohammed

    2013-01-01

    Context: Tribal healers mainly use land plants in their medicinal formulations; use of aquatic plants has been scarcely reported. Aims: The aim of the present study was to conduct an ethnomedicinal survey working with a Bagdi tribal healer of Rajbari District, Bangladesh. Settings and Design: The survey was carried out working with a Bagdi healer, who lived alone in the wetlands of Rajbari District and used primarily aquatic plants for treatment. Materials and Methods: Interview of the healer was carried out with the help of a semi-structured questionnaire and the guided field-walk method. Results: The Bagdi healer was observed to use seven different aquatic plant species coming from five plant families for treatment of ailments such as hemorrhoids, tonsillitis, heart disorders, burning sensations and pain in hands or legs, blurred vision, debility, sexual weakness in males, chronic dysentery, infertility in women, constipation, chronic leucorrhea, blackness and foul odor of menstrual blood, hair loss, graying of hair and to keep the head cool. One plant was used to treat what the healer mentioned as “evil eye”, this refers to their belief in black-magic. Conclusions: This is the first reported instance of a Bagdi healer who primarily uses aquatic plants for treatment. Ethnomedicinal uses of a number of the plants used by the Bagdi healer have been reported for other places in India and Pakistan. Taken together, the various uses of the different plant species opens up scientific possibilities of new drug discoveries from the plants. PMID:25161326

  2. Treatment with aquatic plants by a Bagdi tribal healer of Rajbari District, Bangladesh.

    PubMed

    Mukti, Mohsina; Rahmatullah, Mohammed

    2013-07-01

    Tribal healers mainly use land plants in their medicinal formulations; use of aquatic plants has been scarcely reported. The aim of the present study was to conduct an ethnomedicinal survey working with a Bagdi tribal healer of Rajbari District, Bangladesh. The survey was carried out working with a Bagdi healer, who lived alone in the wetlands of Rajbari District and used primarily aquatic plants for treatment. Interview of the healer was carried out with the help of a semi-structured questionnaire and the guided field-walk method. The Bagdi healer was observed to use seven different aquatic plant species coming from five plant families for treatment of ailments such as hemorrhoids, tonsillitis, heart disorders, burning sensations and pain in hands or legs, blurred vision, debility, sexual weakness in males, chronic dysentery, infertility in women, constipation, chronic leucorrhea, blackness and foul odor of menstrual blood, hair loss, graying of hair and to keep the head cool. One plant was used to treat what the healer mentioned as "evil eye", this refers to their belief in black-magic. This is the first reported instance of a Bagdi healer who primarily uses aquatic plants for treatment. Ethnomedicinal uses of a number of the plants used by the Bagdi healer have been reported for other places in India and Pakistan. Taken together, the various uses of the different plant species opens up scientific possibilities of new drug discoveries from the plants.

  3. Aquatic Plants: Management and Control. Special Circular 222.

    ERIC Educational Resources Information Center

    Wingard, R. G.; And Others

    This publication, produced by the Pennsylvania Cooperative Extension Service, is a non-technical guide to chemical control of aquatic vegetation. The purpose of this circular is to aid the land owner or manager in managing ponds, streams, and other water bodies for desired uses by managing the vegetation in, on, and around the water. Among the…

  4. Aquatic Plants: Management and Control. Special Circular 222.

    ERIC Educational Resources Information Center

    Wingard, R. G.; And Others

    This publication, produced by the Pennsylvania Cooperative Extension Service, is a non-technical guide to chemical control of aquatic vegetation. The purpose of this circular is to aid the land owner or manager in managing ponds, streams, and other water bodies for desired uses by managing the vegetation in, on, and around the water. Among the…

  5. Joint Agency Plan, Aquatic Plant Management on Guntersville Reservoir

    DTIC Science & Technology

    1991-04-01

    regulators will be evaluated and demonstrated. Triclopyr (Renovate), bensulfuron methyl (Mariner), and a new granular formulation of endothail (Aquathol...Various aquatic herbicides (e.g., fluridone endothall, diquat, triclopyr , etc.) will be evaluated against Eurasian watermilfoil and hydrilla. The her

  6. Aquatic Plant Control Research Program. Interactions between Macrophyte Growth and Sediment Nutrient Availability.

    DTIC Science & Technology

    1988-04-01

    freshwater systems. I25 Ul 0 , S 0 REFERENCES Agami, M. and Waisel, Y., 1986. The ecophysiology of roots of submerged vascular plants . Physiol. Veg., 24:607...349-354. Sculthorpe, C. D., 1967. The Biology of Aquatic Vascular Plants . Edward Arnold, London, 610 pp. Short, F. T., 1983. The response of

  7. Aquatic fate of aerially applied hexazinone and terbuthylazine in a New Zealand planted forest

    Treesearch

    Brenda R. Baillie; Daniel G. Neary; Stefan Gous; Carol A. Rolando

    2015-01-01

    Herbicides are used to control competing vegetation during tree establishment, and are often critical to the productivity and economic viability of a planted forest crop. Despite increasing public concern over herbicide use in planted forests and potential impact on the environment, there is limited information on the aquatic fate of many of these herbicides when...

  8. Field effectiveness of Bacillus thuringiensis israelensis (Bti) against Aedes (Stegomyia) aegypti (Linnaeus) in ornamental ceramic containers with common aquatic plants.

    PubMed

    Chen, C D; Lee, H L; Nazni, W A; Seleena, B; Lau, K W; Daliza, A R; Ella Syafinas, S; Mohd Sofian, A

    2009-04-01

    This study was undertaken to determine the impact of larvaciding using a Bti (Bacillus thuringiensis israelensis) formulation (VectoBac WG) against Aedes aegypti larvae in earthen jars containing aquatic plants. Aquatic plants commonly used for landscaping, Pistia stratiotes (L.) (Liliopsida: Araceae) and Sagittaria sp. (Liliopsida: Alismataceae) were placed inside earthen jars filled with 50 L tap water. All earthen jars were treated with Bti formulation at 8g/1000L. Untreated jars with and without aquatic plants were also set up as controls. Fifty laboratory-bred 2nd instar larvae were introduced into each earthen jar. All earthen jars were observed daily. Number of adults emerged was recorded and the larval mortality was calculated. The indicators of effectiveness of Bti for these studies were (i) residual activities of Bti, and (ii) larval mortality in earthen jars with or without aquatic plants. The treated earthen jars containing P. stratiotes and Sagittaria sp. showed significant residual larvicidal effect up to 7 weeks, in comparison to untreated control (p < 0.05). The larval mortality ranged from 77.34% - 100% for jars with aquatic plants vs 80.66% - 100% for jars without aquatic plant. Earthen jars treated with Bti without aquatic plants also exhibited significantly longer residual larvicidal activity of up to 10 weeks (p < 0.05). The larval mortality ranged from 12.66% - 100% for jars with aquatic plants vs 59.34% - 100% for jars without aquatic plant. Thus, earthen jars without aquatic plants exhibited longer residual larvicidal effect compared to those with aquatic plants. This study suggested that containers with aquatic plants for landscaping should be treated more frequently with Bti in view of the shortened residual activity.

  9. Ecosystem-phase interactions: aquatic eutrophication decreases terrestrial plant diversity in California vernal pools.

    PubMed

    Kneitel, Jamie M; Lessin, Carrie L

    2010-06-01

    Eutrophication has long been known to negatively affect aquatic and terrestrial ecosystems worldwide. In freshwater ecosystems, excessive nutrient input results in a shift from vascular plant dominance to algal dominance, while the nutrient-species richness relationship is found to be unimodal. Eutrophication studies are usually conducted in continuously aquatic or terrestrial habitats, but it is unclear how these patterns may be altered by temporal heterogeneity driven by precipitation and temperature variation. The California vernal pool (CVP) ecosystem consists of three distinct phases (aquatic, terrestrial, and dry) caused by variation in climatic conditions. The purpose of this study was to test the hypothesis that resource addition during the aquatic phase results in increased algal abundance, which reduces vascular plant cover and richness of the terrestrial phase upon desiccation. We used mesocosms layered with CVP soil, in which treatments consisted of five levels of nitrogen and phosphorous added every 2 weeks. Resource addition increased available phosphorus levels and algae cover during the aquatic phase. Increased algal crusts resulted in decreased vascular plant percent cover and species richness. Few significant patterns were observed with individual plant species and total biomass. The phosphorus-plant richness relationship was not significant, but species composition was significantly different among the low and high treatment comparisons. These results highlight a neglected effect of eutrophication in seasonal habitats. Interactions among ecosystem phases clearly require more attention empirically and theoretically. Management and restoration of temporally heterogeneous habitat, such as the endemic-rich CVP, need to consider the extensive effects of increased nutrient input.

  10. Associations between Mycobacterium ulcerans and aquatic plant communities of West Africa: implications for Buruli ulcer disease.

    PubMed

    McIntosh, Mollie; Williamson, Heather; Benbow, M Eric; Kimbirauskas, Ryan; Quaye, Charles; Boakye, Daniel; Small, Pamela; Merritt, Richard

    2014-06-01

    Numerous studies have associated Buruli ulcer (BU) disease with disturbed aquatic habitats; however, the natural reservoir, distribution, and transmission of the pathogen, Mycobacterium ulcerans, remain unknown. To better understand the role of aquatic plants in the ecology of this disease, a large-scale survey was conducted in waterbodies of variable flow throughout three regions of Ghana, Africa. Our objectives were to characterize plant communities and identify potential relationships with M. ulcerans and other mycolactone-producing mycobacteria (MPM). Waterbodies with M. ulcerans had significantly different aquatic plant communities, with submerged terrestrial plants identified as indicators of M. ulcerans presence. Mycobacterium ulcerans and MPM were detected on 14 plant taxa in emergent zones from both lotic and lentic waterbodies in endemic regions; however, M. ulcerans was not detected in the non-endemic Volta region. These findings support the hypothesis that plants provide substrate for M. ulcerans colonization and could act as potential indicators for disease risk. These findings also suggest that M. ulcerans is a widespread environmental bacteria species, but that it is absent or reduced in regions of low disease incidence. A better understanding is needed regarding the mechanistic associations among aquatic plants and M. ulcerans for identifying the mode of transmission of BU disease.

  11. Use of dried aquatic plant roots to adsorb heavy metals

    SciTech Connect

    Robichaud, K.D.

    1996-12-31

    The removal of heavy metal ions by dried aquatic macrophytes was investigated. The ability of the biomass, Eichhornia crassipes (water hyacinth), Typha latifolia (cattail), Sparganium minimum (burr reed) and Menyanthes trifoliata to abstract lead and mercury ions is presented here, along with a conceptual filter design. This paper examines an alternative to both the traditional and recent systems designed for metal removal. It involves the use of dried aquatic macrophytes. There are numerous advantages for the use of dried macrophytes in the treatment of industrial wastewater. First, it is cost-effective. There are also funding opportunities through a variety of Environmental Protection Agency`s (EPA) programs. It is more environmentally conscious because a wetland, the harvesting pond, has been created. And, it creates public goodwill by providing a more appealing, less hardware-intensive, natural system.

  12. [Effects of aquatic plants during their decay and decomposition on water quality].

    PubMed

    Tang, Jin-Yan; Cao, Pei-Pei; Xu, Chi; Liu, Mao-Song

    2013-01-01

    Taking 6 aquatic plant species as test objects, a 64-day decomposition experiment was conducted to study the temporal variation patterns of nutrient concentration in water body during the process of the aquatic plant decomposition. There existed greater differences in the decomposition rates between the 6 species. Floating-leaved plants had the highest decomposition rate, followed by submerged plants, and emerged plants. The effects of the aquatic plant species during their decomposition on water quality differed, which was related to the plant biomass density. During the decomposition of Phragmites australis, water body had the lowest concentrations of chemical oxygen demand, total nitrogen, and total phosphorus. In the late decomposition period of Zizania latifolia, the concentrations of water body chemical oxygen demand and total nitrogen increased, resulting in the deterioration of water quality. In the decomposition processes of Nymphoides peltatum and Nelumbo nucifera, the concentrations of water body chemical oxygen demand and total nitrogen were higher than those during the decomposition of other test plants. In contrast, during the decomposition of Potamogeton crispus and Myriophyllum verticillatum, water body had the highest concentrations of ammonium, nitrate, and total phosphorus. For a given plant species, the main water quality indices had the similar variation trends under different biomass densities. It was suggested that the existence of moderate plant residues could effectively promote the nitrogen and phosphorus cycles in water body, reduce its nitrate concentration to some extent, and decrease the water body nitrogen load.

  13. Removal of pharmaceuticals and personal care products in aquatic plant-based systems: a review.

    PubMed

    Zhang, Dongqing; Gersberg, Richard M; Ng, Wun Jern; Tan, Soon Keat

    2014-01-01

    Pharmaceuticals and personal care products (PPCPs) in the aquatic environment are regarded as emerging contaminants and have attracted increasing concern. The use of aquatic plant-based systems such as constructed wetlands (CWs) for treatment of conventional pollutants has been well documented. However, available research studies on aquatic plant-based systems for PPCP removal are still limited. The removal of PPCPs in CWs often involves a diverse and complex set of physical, chemical and biological processes, which can be affected by the design and operational parameters selected for treatment. This review summarizes the PPCP removal performance in different aquatic plant-based systems. We also review the recent progress made towards a better understanding of the various mechanisms and pathways of PPCP attenuation during such phytoremediation. Additionally, the effect of key CW design characteristics and their interaction with the physico-chemical parameters that may influence the removal of PPCPs in functioning aquatic plant-based systems is discussed. Copyright © 2013 Elsevier Ltd. All rights reserved.

  14. Meta-Analysis of the Copper, Zinc, and Cadmium Absorption Capacities of Aquatic Plants in Heavy Metal-Polluted Water.

    PubMed

    Li, Jing; Yu, Haixin; Luan, Yaning

    2015-11-26

    The use of aquatic plants for phytoremediation is an important method for restoring polluted ecosystems. We sought to analyze the capacity of different aquatic plant species to absorb heavy metals and to summarize available relevant scientific data on this topic. We present a meta-analysis of Cu, Zn, and Cd absorption capacities of aquatic plants to provide a scientific basis for the selection of aquatic plants suitable for remediation of heavy-metal pollution. Plants from the Gramineae, Pontederiaceae, Ceratophyllaceae, Typhaceae and Haloragaceae showed relatively strong abilities to absorb these metals. The ability of a particular plant species to absorb a given metal was strongly correlated with its ability to absorb the other metals. However, the absorption abilities varied with the plant organ, with the following trend: roots > stems > leaves. The pH of the water and the life habits of aquatic plants (submerged and emerged) also affect the plant's ability to absorb elements. Acidic water aids the uptake of heavy metals by plants. The correlation observed between element concentrations in plants with different aquatic life habits suggested that the enrichment mechanism is related to the surface area of the plant exposed to water. We argue that this meta-analysis would aid the selection of aquatic plants suitable for heavy-metal absorption from polluted waters.

  15. Aquatic adventitious roots of the wetland plant Meionectes brownii can photosynthesize: implications for root function during flooding.

    PubMed

    Rich, Sarah Meghan; Ludwig, Martha; Pedersen, Ole; Colmer, Timothy David

    2011-04-01

    • Many wetland plants produce aquatic adventitious roots from submerged stems. Aquatic roots can form chloroplasts, potentially producing endogenous carbon and oxygen. Here, aquatic root photosynthesis was evaluated in the wetland plant Meionectes brownii, which grows extensive stem-borne aquatic roots during submergence. • Underwater photosynthetic light and CO(2) response curves were determined for aquatic-adapted leaves, stems and aquatic roots of M. brownii. Oxygen microelectrode and (14)CO(2)-uptake experiments determined shoot inputs of O(2) and photosynthate into aquatic roots. • Aquatic adventitious roots contain a complete photosynthetic pathway. Underwater photosynthetic rates are similar to those of stems, with a maximum net photosynthetic rate (P(max)) of 0.38 μmol O(2) m(-2) s(-1); however, this is c. 30-fold lower than that of aquatic-adapted leaves. Under saturating light with 300 mmol m(-3) dissolved CO(2), aquatic roots fix carbon at 0.016 μmol CO(2) g(-1) DM s(-1). Illuminated aquatic roots do not rely on exogenous inputs of O(2). • The photosynthetic ability of aquatic roots presumably offers an advantage to submerged M. brownii as aquatic roots, unlike sediment roots, need little O(2) and carbohydrate inputs from the shoot when illuminated. © 2010 The Authors. New Phytologist © 2010 New Phytologist Trust.

  16. A field guide to valuable underwater aquatic plants of the Great Lakes

    USGS Publications Warehouse

    Schloesser, Donald W.

    1986-01-01

    The purpose of this field guide is to aid in the identification of common underwater plants in the Great Lakes. These plants are found mostly in shallow, nearshore waters along sheltered bays, peninsulas, and the four connecting rivers of the Great Lakes, including the St. Lawrence River (Figure 1). Connecting rivers are especially favorable for aquatic plants because they are shallow, have a consistent flow of water, and are protected from heavy wave action typical of other Great Lakes shorelines.

  17. Plan of Study for Determining Economic Values of Aquatic Plant Management

    DTIC Science & Technology

    1990-01-01

    can occur without being impeded or diminished by the plant biomass. Removal of aquatic plants or management of plants at nonprob - lem levels makes... sampling designs. For specific waterways or lakes, public perception surveys will be administered to a sample of the users of the proj- ect. The sample ...rigorous sampling designs, while not providing the statistical level of reliability, can still give an indication of public perceptions and preferences

  18. Evaluation of the Environmental DNA Method for Estimating Distribution and Biomass of Submerged Aquatic Plants.

    PubMed

    Matsuhashi, Saeko; Doi, Hideyuki; Fujiwara, Ayaka; Watanabe, Sonoko; Minamoto, Toshifumi

    2016-01-01

    The environmental DNA (eDNA) method has increasingly been recognized as a powerful tool for monitoring aquatic animal species; however, its application for monitoring aquatic plants is limited. To evaluate eDNA analysis for estimating the distribution of aquatic plants, we compared its estimated distributions with eDNA analysis, visual observation, and past distribution records for the submerged species Hydrilla verticillata. Moreover, we conducted aquarium experiments using H. verticillata and Egeria densa and analyzed the relationships between eDNA concentrations and plant biomass to investigate the potential for biomass estimation. The occurrences estimated by eDNA analysis closely corresponded to past distribution records, and eDNA detections were more frequent than visual observations, indicating that the method is potentially more sensitive. The results of the aquarium experiments showed a positive relationship between plant biomass and eDNA concentration; however, the relationship was not always significant. The eDNA concentration peaked within three days of the start of the experiment in most cases, suggesting that plants do not release constant amounts of DNA. These results showed that eDNA analysis can be used for distribution surveys, and has the potential to estimate the biomass of aquatic plants.

  19. Evaluation of the Environmental DNA Method for Estimating Distribution and Biomass of Submerged Aquatic Plants

    PubMed Central

    Matsuhashi, Saeko; Doi, Hideyuki; Fujiwara, Ayaka; Watanabe, Sonoko; Minamoto, Toshifumi

    2016-01-01

    The environmental DNA (eDNA) method has increasingly been recognized as a powerful tool for monitoring aquatic animal species; however, its application for monitoring aquatic plants is limited. To evaluate eDNA analysis for estimating the distribution of aquatic plants, we compared its estimated distributions with eDNA analysis, visual observation, and past distribution records for the submerged species Hydrilla verticillata. Moreover, we conducted aquarium experiments using H. verticillata and Egeria densa and analyzed the relationships between eDNA concentrations and plant biomass to investigate the potential for biomass estimation. The occurrences estimated by eDNA analysis closely corresponded to past distribution records, and eDNA detections were more frequent than visual observations, indicating that the method is potentially more sensitive. The results of the aquarium experiments showed a positive relationship between plant biomass and eDNA concentration; however, the relationship was not always significant. The eDNA concentration peaked within three days of the start of the experiment in most cases, suggesting that plants do not release constant amounts of DNA. These results showed that eDNA analysis can be used for distribution surveys, and has the potential to estimate the biomass of aquatic plants. PMID:27304876

  20. Uptake, translocation and metabolism of decabromodiphenyl ether (BDE-209) in seven aquatic plants.

    PubMed

    Deng, Daiyong; Liu, Jin; Xu, Meiying; Zheng, Guolu; Guo, Jun; Sun, Guoping

    2016-06-01

    Terrestrial plant uptake of PBDEs from contaminated soils has been widely reported recently. In this study the fate of deca-BDE within a plant/PBDEs/aquatic environment system was investigated through simulated pot experiments. Accumulations of the total PBDEs and deca-BDE were observed in tissues of seven test aquatic plant species, namely Phragmites australis, Cyperus papyrus, Alternanthera philoxeroides, Colocasia esculenta, Scirpus validus, Acorus calamus and Oryza sativa. In all seven plants, O. sativa leads the uptake and accumulation both in the total PBDEs (444.8 ng g(-1)) and deca-BDE (368.0 ng g(-1)) in roots. Among the six common phytoremediation aquatic plants, A. calamus leads the uptake (236.2 ng g(-1)), and P. australis leads the translocation (Cshoot/Croot = 0.35), while A. philoxeroides (43.4%) and P. australis (80.0%) lead in the metabolism efficiencies in the root and shoot, respectively. The detection of seventeen lesser brominated PBDE congeners provided the debromination evidence, and the specific PBDEs profiles in test plant species indicated there is no common metabolic pattern. Furthermore, a relative high proportion of lesser brominated PBDE congeners in shoots suggested the possible metabolic difference between roots and shoots. Finally, a noticeable percentage of penta- and octa-BDE derived from deca-BDE also hint the ecological risk in deca-BDE use. This comparative research on the aquatic plants provide a broad vision on the understanding of plant/PBDEs/aquatic environment interaction system, and may be applied to remediate PBDEs in contaminated waters and sediments.

  1. Meta-Analysis of the Copper, Zinc, and Cadmium Absorption Capacities of Aquatic Plants in Heavy Metal-Polluted Water

    PubMed Central

    Li, Jing; Yu, Haixin; Luan, Yaning

    2015-01-01

    The use of aquatic plants for phytoremediation is an important method for restoring polluted ecosystems. We sought to analyze the capacity of different aquatic plant species to absorb heavy metals and to summarize available relevant scientific data on this topic. We present a meta-analysis of Cu, Zn, and Cd absorption capacities of aquatic plants to provide a scientific basis for the selection of aquatic plants suitable for remediation of heavy-metal pollution. Plants from the Gramineae, Pontederiaceae, Ceratophyllaceae, Typhaceae and Haloragaceae showed relatively strong abilities to absorb these metals. The ability of a particular plant species to absorb a given metal was strongly correlated with its ability to absorb the other metals. However, the absorption abilities varied with the plant organ, with the following trend: roots > stems > leaves. The pH of the water and the life habits of aquatic plants (submerged and emerged) also affect the plant’s ability to absorb elements. Acidic water aids the uptake of heavy metals by plants. The correlation observed between element concentrations in plants with different aquatic life habits suggested that the enrichment mechanism is related to the surface area of the plant exposed to water. We argue that this meta-analysis would aid the selection of aquatic plants suitable for heavy-metal absorption from polluted waters. PMID:26703632

  2. Oxidation mechanism and overall removal rates of endocrine disrupting chemicals by aquatic plants.

    PubMed

    Reis, A R; Tabei, K; Sakakibara, Y

    2014-01-30

    The purpose of this study was to evaluate experimentally and theoretically the oxidation mechanisms and overall removal rates of phenolic endocrine disrupting chemicals (EDCs) by aquatic plants. EDCs used in this study were bisphenol-A (BPA), 2,4-dichlorophenol (2,4-DCP), 4-tert-octylphenol (4-t-OP), and pentachlorophenol (PCP). Referring to reported detection levels in aquatic environments and contaminated sites, the feed concentration of each EDC was set from 1 to 100μg/L. Experimental results showed that, except for PCP, phenolic EDCs were stably and concurrently removed by different types of aquatic plants over 70 days in long-term continuous treatments. Primal enzymes responsible for oxidation of BPA, 2,4-DCP, and 4-t-OP were peroxidases (POs). Moreover, enzymatic removal rates of BPA, 2,4-DCP, and 4-t-OP by POs were more than 2 orders of magnitude larger than those by aquatic plants. Assuming that overall removal rates of EDCs are controlled by mass transfer rates onto liquid films on the surface of aquatic plants, an electrochemical method based on the limiting current theory was developed to measure the mass transfer rates of EDCs. Because of extremely large removal rates of EDCs by POs, observed removal rates by aquatic plants were in reasonably good agreement with calculated results by a mathematical model developed based on an assumption that mass transfer limitation is a rate-limiting step. Crown Copyright © 2013. Published by Elsevier B.V. All rights reserved.

  3. Occurrence of antibiotics in water, sediments, aquatic plants, and animals from Baiyangdian Lake in North China.

    PubMed

    Li, Wenhui; Shi, Yali; Gao, Lihong; Liu, Jiemin; Cai, Yaqi

    2012-11-01

    This study investigated the presence and distribution of 22 antibiotics, including eight quinolones, nine sulfonamides and five macrolides, in the water, sediments, and biota samples from Baiyangdian Lake, China. A total of 132 samples were collected in 2008 and 2010, and laboratory analyses revealed that antibiotics were widely distributed in the lake. Sulfonamides were the dominant antibiotics in the water (0.86-1563 ng L(-1)), while quinolones were prominent in sediments (65.5-1166 μg kg(-1)) and aquatic plants (8.37-6532 μg kg(-1)). Quinolones (17.8-167 μg kg(-1)) and macrolides [from below detection limit (BDL) to 182 μg kg(-1)] were often found in aquatic animals and birds. Salvinia natans exhibited the highest bioaccumulation capability for quinolones among three species of aquatic plants. Geographical differences of antibiotic concentrations were greatly due to anthropogenic activities. Sewage discharged from Baoding City was likely the main source of antibiotics in the lake. Risk assessment of antibiotics on aquatic organisms suggested that algae and aquatic plants might be at risk in surface water, while animals were likely not at risk.

  4. Pentachlorophenol: Uptake/elimination kinetics and metabolism in an aquatic plant, Eichhornia crassipes

    SciTech Connect

    Roy, S.; Haenninen, O. . Dept. of Physiology)

    1994-05-01

    Eichhornia crassipes [(Mart) Solms], an aquatic plant widely used for the treatment of wastewaters, was used to study uptake/elimination kinetics and metabolism of pentachlorophenol (PCP). PCP is a well-known industrial by-product and a major pollutant of the aquatic environment. The initial phase of PCP uptake by the plant was rapid and reached a nearly steady state between 24 and 48 h of exposure to PCP. The major by-products of PCP metabolisms in Eichhornia crassipes were identified as ortho- and para- substituted chlorohydroxyphenols (chlorocatechols and -hydroquiones), -anisoles, and -veratroles. Partially dechlorinated products of PCP were also detected. A major portion of the absorbed PCP and metabolites was found in bound/conjugated form. The response of the enzyme systems involved in the xenobiotic metabolism and antioxidative system were also studied following PCP exposure. A significant increase was observed in the activity of glutathione S-transferase (GST), a major conjugating enzyme, and in the activities of superoxide dismutase and ascorbate peroxidase of PCP exposed plants. Such responses of plant enzymes may be implemented as useful markers of aquatic pollution. The result related to the uptake and metabolism of PCP obtained from the present study suggests a crucial role of aquatic plants in determining the fate of environmental chemicals.

  5. Aquatic food production modules in bioregenerative life support systems based on higher plants

    NASA Astrophysics Data System (ADS)

    Bluem, V.; Paris, F.

    Most bioregenerative life support systems (BLSS) are based on gravitropic higher plants which exhibit growth and seed generation disturbances in microgravity. Even when used for a lunar or martian base the reduced gravity may induce a decreased productivity in comparison to Earth. Therefore, the implementation of aquatic biomass production modules in higher plant and/or hybrid BLSS may compensate for this and offer, in addition, the possibility to produce animal protein for human nutrition. It was shown on the SLS-89 and SLS-90 space shuttle missions with the C.E.B.A.S.-MINI MODULE that the edible non gravitropic rootless higher aquatic plant Ceratophyllum demeresum exhibits an undisturbed high biomass production rate in space and that the teleost fish species, Xiphophorus helleri, adapts rapidly to space conditions without loss of its normal reproductive functions. Based on these findings a series of ground-based aquatic food production systems were developed which are disposed for utilization in space. These are plant production bioreactors for the species mentioned above and another suitable candidate, the lemnacean (duckweed) species, Wolffia arrhiza. Moreover, combined intensive aquaculture systems with a closed food loop between herbivorous fishes and aquatic and land plants are being developed which may be suitable for integration into a BLSS of higher complexity.

  6. Aquatic food production modules in bioregenerative life support systems based on higher plants.

    PubMed

    Bluem, V; Paris, F

    2001-01-01

    Most bioregenerative life support systems (BLSS) are based on gravitropic higher plants which exhibit growth and seed generation disturbances in microgravity. Even when used for a lunar or martian base the reduced gravity may induce a decreased productivity in comparison to Earth. Therefore, the implementation of aquatic biomass production modules in higher plant and/or hybrid BLSS may compensate for this and offer, in addition, the possibility to produce animal protein for human nutrition. It was shown on the SLS-89 and SLS-90 space shuttle missions with the C.E.B.A.S.-MINI MODULE that the edible non gravitropic rootless higher aquatic plant Ceratophyllum demeresum exhibits an undisturbed high biomass production rate in space and that the teleost fish species, Xiphophorus helleri, adapts rapidly to space conditions without loss of its normal reproductive functions. Based on these findings a series of ground-based aquatic food production systems were developed which are disposed for utilization in space. These are plant production bioreactors for the species mentioned above and another suitable candidate, the lemnacean (duckweed) species, Wolffia arrhiza. Moreover, combined intensive aquaculture systems with a closed food loop between herbivorous fishes and aquatic and land plants are being developed which may be suitable for integration into a BLSS of higher complexity. Grant numbers: WS50WB9319-3, IVA1216-00588.

  7. State of Washington Aquatic Plant Management Program. Supplement

    DTIC Science & Technology

    1991-03-01

    accumulations of plant material at dams, obstruction of drainage, restriction of natural water flows, reduced navigability, and damages to fish and wildlife... microorganisms , and competitive plants ) show promise, and are in various stages of development. Grass carp are available for effective-control of watermilfoil...control methods (herbivorous fish and insects, pathogenic microorganisms , and competitiva plants ) are il various stages of development. Grass carp are now

  8. Nutrient enrichment affects the mechanical resistance of aquatic plants.

    PubMed

    Lamberti-Raverot, Barbara; Puijalon, Sara

    2012-10-01

    For many plant species, nutrient availability induces important anatomical responses, particularly the production of low-density tissues to the detriment of supporting tissues. Due to the contrasting biomechanical properties of plant tissues, these anatomical responses may induce important modifications in the biomechanical properties of plant organs. The aim of this study was to determine the effects of nutrient enrichment on the anatomical traits of two freshwater plant species and its consequences on plant biomechanical performance. Two plant species were grown under controlled conditions in low versus high nutrient levels. The anatomical and biomechanical traits of the plant stems were measured. Both species produced tissues with lower densities under nutrient-rich conditions, accompanied by modifications in the structure of the aerenchyma for one species. As expected, nutrient enrichment also led to important modifications in the biomechanical properties of the stem for both species. In particular, mechanical resistance (breaking force and strength) and stiffness of stems were significantly reduced under nutrient rich conditions. The production of weaker stem tissues as a result of nutrient enrichment may increase the risk of plants to mechanical failure, thus challenging plant maintenance in mechanically stressful or disturbed habitats.

  9. Nutrient enrichment affects the mechanical resistance of aquatic plants

    PubMed Central

    Puijalon, Sara

    2012-01-01

    For many plant species, nutrient availability induces important anatomical responses, particularly the production of low-density tissues to the detriment of supporting tissues. Due to the contrasting biomechanical properties of plant tissues, these anatomical responses may induce important modifications in the biomechanical properties of plant organs. The aim of this study was to determine the effects of nutrient enrichment on the anatomical traits of two freshwater plant species and its consequences on plant biomechanical performance. Two plant species were grown under controlled conditions in low versus high nutrient levels. The anatomical and biomechanical traits of the plant stems were measured. Both species produced tissues with lower densities under nutrient-rich conditions, accompanied by modifications in the structure of the aerenchyma for one species. As expected, nutrient enrichment also led to important modifications in the biomechanical properties of the stem for both species. In particular, mechanical resistance (breaking force and strength) and stiffness of stems were significantly reduced under nutrient rich conditions. The production of weaker stem tissues as a result of nutrient enrichment may increase the risk of plants to mechanical failure, thus challenging plant maintenance in mechanically stressful or disturbed habitats. PMID:23028018

  10. Aquatic Plant Control Research Program: The Habitat Value of Aquatic Macrophytes for Macroinvertebrates

    DTIC Science & Technology

    1989-11-01

    invertebrates and included quantitative estimates of invertebrate density and species composition. b. Schramm, Jirka, and Hoyer (1987) reported significant...1976; Dvorak and Best 1982; Engel 1985; Schramm, Jirka, and Hoyer 1987). 47. Fewer studies have reported large numbers of naidids on submersed plants...Schramm, Jirka, and Hoyer (1987) observed temporal variations in the abundance of invertebrates on macrophytes but concluded that consistent temporal

  11. Plant response strategies to stress and disturbance: the case of aquatic plants.

    PubMed

    Trémolières, Michèle

    2004-12-01

    The environmental factors controlling the establishment and development of plants in different ecosystems are of two types, stress and disturbance. The effects of stress or disturbance on aquatic systems are discussed in relation to the following questions: Can we predict the state and rate of recolonization after a disturbance? What are the strategies of recolonization developed by plants? How high is the resilience of a disturbed system? Two theories, the intermediate disturbance hypothesis, and the patch dynamics concept proposed to predict the composition, structure and dynamics of plants due to physical-chemical factors, were tested on two scales, that of communities and that of species, within two alluvial floodplains (the Rhine and the Rhone systems in France). With regard to the change of community on a larger scale (i.e. the whole network of the cut-off channels in the floodplain), large gradients of connection and disturbance induce high diversities within communities. Moreover, the highest flood disturbance induces a higher species richness and the occurrence of a particular species. The change in species is analysed using biological traits (morphological, reproductive or physiological). In the floodplain of the river Rhone, the response of plants corresponds well to theory, i.e. that habitats with an intermediate disturbance are richer than more or less disturbed habitats. So we can predict, through the biological traits, the functioning of a habitat. The last remaining question is that of the resilience of the system, which can be discussed in terms of species competition and the risk of biological invasion after an opening of habitat.

  12. Chemical fractionation of radionuclides and stable elements in aquatic plants of the Yenisei River.

    PubMed

    Bolsunovsky, Alexander

    2011-09-01

    The Yenisei River is contaminated with artificial radionuclides released by one of the Russian nuclear plants. The aquatic plants growing in the radioactively contaminated parts of the river contain artificial radionuclides. The aim of the study was to investigate accumulation of artificial radionuclides and stable elements by submerged plants of the Yenisei River and estimate the strength of their binding to plant biomass by using a new sequential extraction scheme. The aquatic plants sampled were: Potamogeton lucens, Fontinalis antipyretica, and Batrachium kauffmanii. Gamma-spectrometric analysis of the samples of aquatic plants has revealed more than 20 radionuclides. We also investigated the chemical fractionation of radionuclides and stable elements in the biomass and rated radionuclides and stable elements based on their distribution in biomass. The greatest number of radionuclides strongly bound to biomass cell structures was found for Potamogeton lucens and the smallest for Batrachium kauffmanii. For Fontinalis antipyretica, the number of distribution patterns that were similar for both radioactive isotopes and their stable counterparts was greater than for the other studied species. The transuranic elements (239)Np and (241)Am were found in the intracellular fraction of the biomass, and this suggested their active accumulation by the plants.

  13. Characterisation of seven Inocybe ectomycorrhizal morphotypes from a semiarid woody steppe.

    PubMed

    Seress, Diána; Dima, Bálint; Kovács, Gábor M

    2016-04-01

    Ectomycorrhizas (ECM) of Inocybe species (Inocybaceae, Basidiomycota) formed by three host plant species (Populus alba, Salix rosmarinifolia and Pinus nigra) in a semiarid woody steppe of Hungary were studied. To identify the fungal partners, we performed phylogenetic analyses of nucleotide sequences for the internal transcribed spacer region of nuclear DNA (nrDNA ITS) together with sequences gained from public databases. Seven Inocybe ectomycorrhiza morphotypes were morpho-anatomically characterised. Five morphotypes were identified (I. phaeoleuca, I. psammophila, I. semifulva, I. splendens and I. subporospora), whereas two morphotypes represented unidentified Inocybe species. Differences were discernible among the morphotypes, and they showed general anatomical characteristics of Inocybe ECM, such as the slightly organised plectenchymatic mantle (types A, B and E and the gelatinous C). The ECM of I. subporospora and I. phaeoleuca were detected from the introduced Pinus nigra. These two fungi are probably native to the area but capable of forming a novel ectomycorrhizal association with the invasive host.

  14. Surprising spectra of root-associated fungi in submerged aquatic plants.

    PubMed

    Kohout, Petr; Sýkorová, Zuzana; Ctvrtlíková, Martina; Rydlová, Jana; Suda, Jan; Vohník, Martin; Sudová, Radka

    2012-04-01

    Similarly to plants from terrestrial ecosystems, aquatic species harbour wide spectra of root-associated fungi (RAF). However, comparably less is known about fungal diversity in submerged roots. We assessed the incidence and diversity of RAF in submerged aquatic plants using microscopy, culture-dependent and culture-independent techniques. We studied RAF of five submerged isoetid species collected in four oligotrophic freshwater lakes in Norway. Levels of dark septate endophytes (DSE) colonization differed among the lakes and were positively related to the organic matter content and negatively related to pH. In total, we identified 41 fungal OTUs using culture-dependent and culture-independent techniques, belonging to Mucoromycotina, Chytridiomycota, Glomeromycota, Ascomycota as well as Basidiomycota. Sequences corresponding to aquatic hyphomycetes (e.g. Nectria lugdunensis, Tetracladium furcatum and Varicosporium elodeae) were obtained. Eight arbuscular mycorrhizal taxa belonging to the orders Archaeosporales, Diversisporales and Glomerales were also detected. However, the vast majority of the fungal species detected (e.g. Ceratobasidium sp., Cryptosporiopsis rhizophila, Leptodontidium orchidicola, and Tuber sp.) have previously been known only from roots of terrestrial plants. The abundance and phylogenetic distribution of mycorrhizal as well as nonmycorrhizal fungi in the roots of submerged plants have reshaped our views on the fungal diversity in aquatic environment. © 2011 Federation of European Microbiological Societies. Published by Blackwell Publishing Ltd. All rights reserved.

  15. Native aquatic plants and ecological condition of southwestern wetlands and riparian areas

    Treesearch

    Alvin L. Medina

    1996-01-01

    The determination of the ecological condition of wetland and riparian habitats has been the focus of research by many scientists, because of the importance to understand the processes and related functions of these systems. Research on montane wetland and riparian systems has shown the relative importance of native aquatic plants in maintaining these systems in a...

  16. Methane production from and beneficiation of anaerobic digestion of aquatic plant material

    SciTech Connect

    Klass, D.L.; Ghosh, S.

    1984-01-03

    A process is disclosed for improved CH/sub 4/ production by anaerobic digestion of aquatic plant material, at least a portion or all which was grown in organically polluted water. Mixtures of aquatic plant material whose 1 portion was grown in nonpolluted and a 2nd portion comprising approximately 10 wt.% or more grown in organically polluted water can be used. The liquid effluent from the digester may be advantageously returned to the aquatic plant-growing pond to maintain the desired organic pollution. The process provides for improved CH/sub 4/ production from aquatic plant material which is, by itself, recalcitrant to anaerobic digestion. Thus, 2 digesters were operated under the same conditions, the 1st being fed with water hyacinth grown in nonorganic polluted hardwater of BOD 5 mg/l and hardness of 20 grains/gal. and the 2nd being fed with water hyacinth grown in sewage-polluted water of BOD 20 mg/l. Each digester was operated in a semicontinuous completely mixed anaerobic manner with a culture volume of 5 liters for a detention time of 12 days, a loading of 0.1 lb volatile solid/cubic feet-day, and 35/sup 0/ at pH of 6.8-7.1. The runs were contained for several detention times and exhibited stable performance. CH/sub 4/ yield increased approximately 69% and the gas-production rate increased approximately 82% by using water hyacinth feed grown in sewage-polluted water.

  17. 33 CFR Appendix A to Part 273 - Aquatic Plant Control Program Legislative Authority

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Legislative Authority A Appendix A to Part 273 Navigation and Navigable Waters CORPS OF ENGINEERS, DEPARTMENT OF THE ARMY, DEPARTMENT OF DEFENSE AQUATIC PLANT CONTROL Pt. 273, App. A Appendix A to Part 273... Stat. 1092) states as follows: Sec. 302(a) There is hereby authorized a comprehensive program...

  18. Uranium accumulation by aquatic plants from uranium-contaminated water in Central Portugal.

    PubMed

    Pratas, João; Favas, Paulo J C; Paulo, Carlos; Rodrigues, Nelson; Prasad, M N V

    2012-03-01

    Several species of plants have developed a tolerance to metal that enables them to survive in metal contaminated and polluted sites. Some of these aquatic plants have been reported to accumulate significant amounts of specific trace elements and are, therefore, useful for phytofiltration. This work focuses the potential of aquatic plants for the phytofiltration of uranium (U) from contaminated water. We observed that Callitriche stagnalis, Lemna minor, and Fontinalis antipyretica, which grow in the uraniferous geochemical province of Central Portugal, have been able to accumulate significant amounts of U. The highest concentration of U was found in Callitriche stagnalis (1948.41 mg/kg DW), Fontinalis antipyretica (234.79 mg/kg DW), and Lemna minor (52.98 mg/kg DW). These results indicate their potential for the phytofiltration of U through constructed treatment wetlands or by introducing these plants into natural water bodies in the uraniferous province of Central Portugal.

  19. Herbicide risk assessment for non-target aquatic plants: sulfosulfuron--a case study.

    PubMed

    Davies, Joanna; Honegger, Joy L; Tencalla, Francesca G; Meregalli, Giovanna; Brain, Philip; Newman, Jonathan R; Pitchford, Hannah F

    2003-02-01

    Herbicides entering the aquatic environment by spray drift, run-off and leaching to field drains may cause adverse effects on non-target aquatic vegetation. The potential for such effects has typically been evaluated from tests with floating, monocotyledonous Lemna sp. However, concern has been expressed as to whether this species could be used to indicate potential effects on other vegetation types, particularly rooted, submerged, emergent or dicotyledonous species. In 1997, the Centre for Aquatic Plant Management undertook development of new tests based on the additional species, Glyceria maxima (Hartm) Holmb, Lagarosiphon major (Ridl) Moss and Myriophyllum spicatum L. The resulting methodology was used to assess the effects of the sulfonylurea herbicide, sulfosulfuron on these species. Data presented here demonstrate that exposure to initial sulfosulfuron concentrations of 3.33 microg litre(-1) for up to 21 days was tolerated by these species and that adverse effects were observed only when plants were exposed to initial concentrations of 3.33 and 10 microg litre(-1) for 70 days. As the occurrence of such high initial concentrations for long periods is unlikely in the aquatic environment, sulfosulfuron is not expected to have adverse effects on the growth of these species. This study has also demonstrated that G maxima, L major and M spicatum grown in small outdoor tanks can be used successfully to assess the effects of crop-protection products on non-target aquatic flora.

  20. Phytoprotective influence of bacteria on growth and cadmium accumulation in the aquatic plant Lemna minor.

    PubMed

    Stout, Lisa M; Dodova, Elena N; Tyson, Julian F; Nüsslein, Klaus

    2010-09-01

    Certain plants are known to accumulate heavy metals, and can be used in remediation of polluted soil or water. Plant-associated bacteria, especially those that are metal tolerant, may enhance the total amount of metal accumulated by the plant, but this process is still unclear. In this study, we investigated metal enhancement vs. exclusion by plants, and the phytoprotective role plant-associated bacteria might provide to plants exposed to heavy metal. We isolated cadmium-tolerant bacteria from the roots of the aquatic plant Lemna minor grown in heavy metal-polluted waters, and tested these isolates for tolerance to cadmium. The efficiency of plants to accumulate heavy metal from their surrounding environment was then tested by comparing L. minor plants grown with added metal tolerant bacteria to plants grown axenically to determine, whether bacteria associated with these plants increase metal accumulation in the plant. Unexpectedly, cadmium tolerance was not seen in all bacterial isolates that had been exposed to cadmium. Axenic plants accumulated slightly more cadmium than plants inoculated with bacterial isolates. Certain isolates promoted root growth, but overall, addition of bacterial strains did not enhance plant cadmium uptake, and in some cases, inhibited cadmium accumulation by plants. This suggests that bacteria serve a phytoprotective role in their relationship with Lemna minor, preventing toxic cadmium from entering plants. Copyright © 2010 Elsevier Ltd. All rights reserved.

  1. Benefits of flooding-induced aquatic adventitious roots depend on the duration of submergence: linking plant performance to root functioning.

    PubMed

    Zhang, Qian; Huber, Heidrun; Beljaars, Simone J M; Birnbaum, Diana; de Best, Sander; de Kroon, Hans; Visser, Eric J W

    2017-07-01

    Temporal flooding is a common environmental stress for terrestrial plants. Aquatic adventitious roots (aquatic roots) are commonly formed in flooding-tolerant plant species and are generally assumed to be beneficial for plant growth by supporting water and nutrient uptake during partial flooding. However, the actual contribution of these roots to plant performance under flooding has hardly been quantified. As the investment into aquatic root development in terms of carbohydrates may be costly, these costs may - depending on the specific environmental conditions - offset the beneficial effects of aquatic roots. This study tested the hypothesis that the balance between potential costs and benefits depends on the duration of flooding, as the benefits are expected to outweigh the costs in long-term but not in short-term flooding. The contribution of aquatic roots to plant performance was tested in Solanum dulcamara during 1-4 weeks of partial submergence and by experimentally manipulating root production. Nutrient uptake by aquatic roots, transpiration and photosynthesis were measured in plants differing in aquatic root development to assess the specific function of these roots. As predicted, flooded plants benefited from the presence of aquatic roots. The results showed that this was probably due to the contribution of roots to resource uptake. However, these beneficial effects were only present in long-term but not in short-term flooding. This relationship could be explained by the correlation between nutrient uptake and the flooding duration-dependent size of the aquatic root system. The results indicate that aquatic root formation is likely to be selected for in habitats characterized by long-term flooding. This study also revealed only limited costs associated with adventitious root formation, which may explain the maintenance of the ability to produce aquatic roots in habitats characterized by very rare or short flooding events.

  2. The long-term impact of urbanisation on aquatic plants: Cambridge and the River Cam.

    PubMed

    Preston, C D; Sheail, J; Armitage, P; Davy-Bowker, J

    2003-10-01

    Historical and contemporary records have been used to assess the impact of urbanisation on the aquatic plants of the River Cam and its narrow floodplain in Cambridge. Of the 62 native aquatic plant species which have been recorded in the study area since 1660, 40 (65%) were still present in the period 1985-1999 whereas 22 (35%) are apparently extinct. There is a striking relationship between the fate of species and their trophic requirements, with species of less eutrophic habitats having suffered disproportionately. Historical records demonstrate that the River Cam became grossly polluted by sewage from Cambridge in the 19th century, but the chemical and biological quality of the river improved from 1897 onwards. However, the majority of the species recorded from the river and nearby ditches persisted until after maximum incidence of sewage pollution, which may even have stimulated the growth of 'weed' in the river. Losses of aquatic plant species from two riparian commons, Coe Fen (35%) and Sheep's Green (50%), have been particularly great. The level of these and other areas of low-lying common land by the river has been systematically raised by the controlled tipping of waste in hollows, followed by levelling and resowing. The main effects of urbanisation on the flora therefore arose from the transformation of riparian pastures into suburban open spaces. Commons which are used purely for amenity purposes have lost almost all their aquatic plant species. Those which are still grazed retain more, and continuance of grazing is probably essential if a varied aquatic flora is to be maintained. The interpretation of botanical records in terms of recorded management history is likely to throw further light on the processes of urbanisation, although the number of sites with a sufficiently detailed botanical record may be limited.

  3. Weed Risk Assessment for Aquatic Plants: Modification of a New Zealand System for the United States

    PubMed Central

    Gordon, Doria R.; Gantz, Crysta A.; Jerde, Christopher L.; Chadderton, W. Lindsay; Keller, Reuben P.; Champion, Paul D.

    2012-01-01

    We tested the accuracy of an invasive aquatic plant risk assessment system in the United States that we modified from a system originally developed by New Zealand’s Biosecurity Program. The US system is comprised of 38 questions that address biological, historical, and environmental tolerance traits. Values associated with each response are summed to produce a total score for each species that indicates its risk of invasion. To calibrate and test this risk assessment, we identified 39 aquatic plant species that are major invaders in the continental US, 31 species that have naturalized but have no documented impacts (minor invaders), and 60 that have been introduced but have not established. These species represent 55 families and span all aquatic plant growth forms. We found sufficient information to assess all but three of these species. When the results are compared to the known invasiveness of the species, major invaders are distinguished from minor and non-invaders with 91% accuracy. Using this approach, the US aquatic weed risk assessment correctly identifies major invaders 85%, and non-invaders 98%, of the time. Model validation using an additional 10 non-invaders and 10 invaders resulted in 100% accuracy for the former, and 80% accuracy for the latter group. Accuracy was further improved to an average of 91% for all groups when the 17% of species with scores of 31–39 required further evaluation prior to risk classification. The high accuracy with which we can distinguish non-invaders from harmful invaders suggests that this tool provides a feasible, pro-active system for pre-import screening of aquatic plants in the US, and may have additional utility for prioritizing management efforts of established species. PMID:22808088

  4. Weed risk assessment for aquatic plants: modification of a New Zealand system for the United States.

    PubMed

    Gordon, Doria R; Gantz, Crysta A; Jerde, Christopher L; Chadderton, W Lindsay; Keller, Reuben P; Champion, Paul D

    2012-01-01

    We tested the accuracy of an invasive aquatic plant risk assessment system in the United States that we modified from a system originally developed by New Zealand's Biosecurity Program. The US system is comprised of 38 questions that address biological, historical, and environmental tolerance traits. Values associated with each response are summed to produce a total score for each species that indicates its risk of invasion. To calibrate and test this risk assessment, we identified 39 aquatic plant species that are major invaders in the continental US, 31 species that have naturalized but have no documented impacts (minor invaders), and 60 that have been introduced but have not established. These species represent 55 families and span all aquatic plant growth forms. We found sufficient information to assess all but three of these species. When the results are compared to the known invasiveness of the species, major invaders are distinguished from minor and non-invaders with 91% accuracy. Using this approach, the US aquatic weed risk assessment correctly identifies major invaders 85%, and non-invaders 98%, of the time. Model validation using an additional 10 non-invaders and 10 invaders resulted in 100% accuracy for the former, and 80% accuracy for the latter group. Accuracy was further improved to an average of 91% for all groups when the 17% of species with scores of 31-39 required further evaluation prior to risk classification. The high accuracy with which we can distinguish non-invaders from harmful invaders suggests that this tool provides a feasible, pro-active system for pre-import screening of aquatic plants in the US, and may have additional utility for prioritizing management efforts of established species.

  5. The aquatic vascular plant Ruppia maritima as an indicator organism for contaminated sediments

    SciTech Connect

    Tagliabue, M.D.; Thursby, G.B.; Walker, H.A.; Johnston, R.K.

    1995-12-31

    An ongoing estuarine ecological risk assessment case study for the Portsmouth Naval Shipyard in the Great Bay Estuary (New Hampshire, Maine) was the catalyst to continue development a rooted aquatic plant sediment toxicity test. Laboratory studies were conducted to evaluate effects of lead, the primary site contaminant on R. maritima in the Great Bay. Although the aquatic vascular plant Zostra marina comprises up to 46% of the Great Bay subtidal habitat, R. maritima`s much smaller size makes it a more practical laboratory organism. Effects on Ruppia may offer useful insights into potential effects on Zostra or other aquatic vascular plants. Presently rooted vascular plants are not found in Clark Cove located adjacent to a landfill disposal site on the shipyard. The absence of rooted vegetation can be contributed to, physical parameters of the site (turbidity, grain size, texture) or chemical parameters (heavy metal/Pb contamination, redox potential). Exposure of bedded and nonbedded plants occurred over a four day and ten day period using lead sulfate. Concentrations for bedded exposures were as follows, 0.3, 0.5, 0.8, 1.0 simultaneously extracted metal/acid volatile sulfide (SEM/AVS) molar ratios, and 0.1, 1.0, 10.0 and 100.0mg/l Pb for water only exposures. Reduction in cumulative leaf growth was observed for the Clark Cove sediments as well as the spiked sediments as compared to reference sediments.

  6. The Effects of Rainfall on the Population Dynamics of an Endangered Aquatic Plant, Schoenoplectus gemmifer (Cyperaceae).

    PubMed

    Kitamura, Koshi; Kakishima, Satoshi; Uehara, Takashi; Morita, Satoru; Tainaka, Kei-Ichi; Yoshimura, Jin

    2016-01-01

    The conservation of aquatic plants in river ecosystems should consider the wash-out (away) problem resulting from severe rainfall. The aquatic plant Schoenoplectus gemmifer is an endangered species endemic to Japan. Our previous study reported that the population size of S. gemmifer in Hamamatsu city, Japan, had decreased by one-tenth because many individuals had been washed out by a series of heavy rains in 2004. However, there is insufficient information on the ecological nature of this endangered aquatic plant for adequate conservation. In this paper, we report the population dynamics of one population in Hamamatsu city from 2004 to 2012 in relation to rainfall. We surveyed the number and growing location of all living individuals in the population 300 times during the study period. To examine the temporal changes of individual plants, we also counted the number of culms for 38 individuals in four observations among 300 records. Decreases and increases in the population size of this plant were associated with washing out and the settlement of gemmae (vegetative propagation), respectively. The major cause of the reduction in the population size was an increase in the number of washed-out individuals and not the decreased settlement of gemmae. The wash-out rates for small and large individuals were not significantly different. Small individuals having a stream form with linear leaves resisted flooding, and large individuals were often partially torn off by flooding events. Modification of river basins to reduce the flow velocity may be effective for the conservation of S. gemmifer.

  7. Accumulation of uranium by aquatic plants in field conditions: prospects for phytoremediation.

    PubMed

    Favas, Paulo J C; Pratas, João; Varun, Mayank; D'Souza, Rohan; Paul, Manoj S

    2014-02-01

    A study was undertaken to determine Uranium concentrations in water and aquatic plants in the uraniferous region of Beiras, Central Portugal. Samples were collected from running water (n=200) at places where aquatic species were observed. Plant samples were collected from 28 species of submerged, free-floating and rooted emergent plants including 2 bryophytes and 1 pteridophyte. Uranium concentrations in surface waters ranged from 0.23 to 1,217 μg L(-1). The aquatic plant species studied, including several previously untested species, exhibited the ability to accumulate U in concentrations many times that of the ambient water. In general submerged plants exhibited higher U content followed by rooted emergent and free floating species. The highest U concentrations were observed in the bryophyte Fontinalis antipyretica (up to 4,979 mg kg(-1)) followed by Callitriche stagnalis (1963mgkg(-1)), Callitriche hamulata (379 mg kg(-1)), Ranunculus peltatus subsp. saniculifolius (243 mg kg(-1)), Callitriche lusitanica (218 mg kg(-1)), and Ranunculus trichophyllus (65.8 mg kg(-1)). In two out of three rooted emergent species U seemed to be preferentially partitioned in rhizome/roots with highest rhizome U content recorded in Typha latifolia (380 mg kg(-1)). Among the free-floating species, the highest U content (42.5 mg kg(-1)) was seen in Lemna minor. The bryophyte F. antipyretica and Callitrichaceae members seem to be promising candidates for the development of phytofiltration methodologies based on U accumulation, abundance and biomass production.

  8. State of Washington, Aquatic Plant Management Program: Design Memorandum.

    DTIC Science & Technology

    1979-10-01

    those on others who dil not receive it (G. K. Zemansky , our mailing list for the Aqtrt ic Plant Maa nagmenr Friends of the Earth). Study. This includes...added to the Mai ling list. Precisely what was the purpose of this survey? The purpose of the questionnaire was to provide a (G. M. Zemansky , Friends of

  9. The aquatic vascular plant Ruppia maritima as an indicator organisms for contaminated sediments

    SciTech Connect

    Tagliabue, M.D.; Thursby, G.B.; Walker, H.A.; Johnston, R.K.

    1994-12-31

    An ongoing estuarine ecological risk assessment case study for the Portsmouth Naval Shipyard in the Great Bay (Kittery, ME, Portsmouth, NH) has been the catalyst for continued methods development with a rooted aquatic plant for a sediment toxicity test. A test using the aquatic vascular plant Ruppia maritima would be similar in it`s utility to the Algal (Champia parvula) Reproduction Test, an accepted, short term test (US EPA Short term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Marine and Estuarine Organisms). Laboratory studies were conducted to evaluate effects of lead, the primary site contaminant on R. maritima in the Great Bay. Morphology and life cycle of R. maritima are similar to that of the aquatic vascular plant Zostra marina which comprises up to 46% of the Great Bay habitat (Short 1992). R. maritima`s reduced size makes it a practical laboratory organism and Ruppia`s effects may offer useful insights into potential effects on Zostra or other aquatic vascular plants. Presently rooted vascular plants are not found in the site of concern (Clark Cove). This can be contributed to either of two factors; the physical parameters of the site, i.e., a depositional zone or the chemical parameters, i.e., metals contamination, specifically lead. Exposure of bedded and nonbedded plants occurred over a four day and ten day period using lead sulfate. Concentrations for bedded exposures were as follows, 0.3, 0.5, 0.8, 1.0 simultaneously extracted metal/acid volatile sulfide (SEM/AVS) molar ratios, and 0.1, 1.0, 10.0 and 100.0mg/l Pb for water only exposures. Some reduction in cumulative leaf growth was observed in the site samples as well as the spiked samples as compared to site controls. Results of this study and associated research which focuses on the further development of the Ruppia test methods will be presented.

  10. A Study on Effect of Water Background on Canopy Spectral of Wetland Aquatic Plant.

    PubMed

    Liu, Guang; Tang, Peng; Cai Zhan-qing; Wang, Tian-tian; Xu, Jun-feng

    2015-10-01

    Aquatic vegetation is the core of the wetland ecosystem, and it's also the main factor influencing the wetland ecosystem functions. In recent years, satellite remote sensing technology has been widely used in the investigation, classification and protection fields of wetland vegetation resources. Because of its unique growth environment, aquatic vegetation, the canopy spectrum of aquatic vegetation will be affected by water background elements including air-water interface, plankton in the water, sediment content, transparency, water depth, sediment, and the other optically active ingredients. When the remote sensing technology for wetland aquatic vegetation canopy spectral studies, should be considered the growth environment differences between aquatic and terrestrial vegetation. However, previous studies did not get the attention it deserves. This paper choose a typical water plant (Iris tentorium Maxim) as the research object, simulate the growth environment of wetland aquatic plants, use the feature spectrometer measurements the spectral reflectance of Iris tentorium Maxim vegetation canopy under different water depth gradient background (400-2 400 nm). Experimental results show that there is a significant negative correlation between background water depth and Iris canopy reflectance. Visible light band absolute correlation coefficient is above 0.9, near infrared band absolute correlation coefficient is above 0.8. In visible light and near infrared band, with water depth increases, the Iris canopy reflectance decreases obviously. Finally based on the highest correlation band of visible light and near infrared region (505, 717, 1 075 and 2 383 nm) established the linear equation between background water depth and the canopy reflectance, obtained the related parameters.

  11. Creosote toxicity to photosynthesis and plant growth in aquatic microcosms.

    PubMed

    Marwood, Christopher A; Bestari, K T Jim; Gensemer, Robert W; Solomon, Keith R; Greenberg, Bruce M

    2003-05-01

    To assess photosynthesis as a bioindicator of toxicity from polycyclic aromatic hydrocarbons (PAHs), the response of chlorophyll-a fluorescence to creosote exposure was compared with effects on population-level plant growth. Large, outdoor, freshwater microcosms containing Eurasian watermilfoil (Myriophyllum spicatum) received either a single application or multiple applications of liquid creosote at nominal concentrations from 0.109 to 32.7 mg L(-1). For several weeks following treatment, photosynthetic electron transport was measured using pulse amplitude-modulated chlorophyll-a fluorescence. The maximum efficiency of photosystem II electron transport (Fv/Fm) and the quantum yield of photochemistry (deltaF/F'm) were diminished in plants shortly after the addition of creosote. In microcosms that received a single treatment of creosote only, the 50% effective concentrations (EC50s), expressed as the aqueous concentration of 15 of the most abundant PAHs, were 0.28 mg L(-1) for Fv/Fm and 0.30 mg L(-1) for deltaF/F'm. Chlorophyll-a fluorescence was diminished to a greater extent in microcosms that received multiple treatments of creosote, with EC50s of 0.13 mg L(-1) for Fv/Fm and 0.10 mg L(-1) for deltaF/F'm. Plant biomass accumulation was inhibited in a concentration-dependent manner in all microcosms treated with creosote, but this inhibition occurred to a greater degree in microcosms treated with multiple creosote applications. The response of chlorophyll-a fluorescence, measured only 8 d after creosote treatment, was similar to plant growth over the entire growing season, indicating that this technique can be used to estimate potential effects of contaminants before detrimental impacts on populations.

  12. Update to the Propagation and Establishment of Aquatic Plants Handbook

    DTIC Science & Technology

    2005-03-01

    Propagule Production 13 Aphids and caterpillars can reach nuisance proportions in tank cultures, and may require control by spraying with water ( aphids ...susceptible to aphid infestation. Snails can be a problem at high densities. Field Planting Propagule Mature potted transplants Season Early spring...start with a minimum of 12 weeks required to produce mature transplants. Topped out leaves are susceptible to aphid infestation. Snails can be a problem

  13. A new mechanism of macrophyte mitigation: how submerged plants reduce malathion's acute toxicity to aquatic animals.

    PubMed

    Brogan, William R; Relyea, Rick A

    2014-08-01

    A growing body of evidence suggests that aquatic plants can mitigate the toxicity of insecticides to sensitive aquatic animals. The current paradigm is that this ability is driven primarily by insecticide sorption to plant tissues, especially for hydrophobic compounds. However, recent work shows that submerged plants can strongly mitigate the toxicity of the relatively hydrophilic insecticide malathion, despite the fact that this compound exhibits a slow sorption rate to plants. To examine this disparity, we tested the hypothesis that the mitigating effect of submerged plants on malathion's toxicity is driven primarily by the increased water pH from plant photosynthesis causing the hydrolysis of malathion, rather than by sorption. To do this, we compared zooplankton (Daphnia magna) survival across five environmentally relevant malathion concentrations (0, 1, 4, 6, or 36 μg L(-1)) in test containers where we chemically manipulated water pH in the absence of plants or added the submerged plant (Elodea canadensis) but manipulated plant photosynthetic activity via shading or no shading. We discovered that malathion was equally lethal to Daphnia at all concentrations tested when photosynthetically inactive (i.e. shaded) plants were present (pH at time of dosing=7.8) or when pH was chemically decreased (pH=7.7). In contrast, when photosynthetically active (i.e. unshaded) plants were present (pH=9.8) or when pH was chemically increased (pH=9.5), the effects of 4 and 6 μg L(-1) of malathion on Daphnia were mitigated strongly and to an equal degree. These results demonstrate that the mitigating effect of submerged plants on malathion's toxicity can be explained entirely by a mechanism of photosynthesizing plants causing an increase in water pH, resulting in rapid malathion hydrolysis. Our findings suggest that current ecotoxicological models and phytoremediation strategies may be overlooking a critical mechanism for mitigating pesticides. Copyright © 2014 Elsevier Ltd

  14. Cyanide-resistant respiration in photosynthetic organs of freshwater aquatic plants. [Myriophyllum spicatum

    SciTech Connect

    Azcon-Bieto, J.; Murillo, J.; Penuelas, J.

    1987-07-01

    The rate and sensitivity to inhibitors (KCN and salicylhydroxamic acid(SHAM)) of respiratory oxygen uptake has been investigated in photosynthetic organs of several freshwater aquatic plant species. The oxygen uptake rates on a dry weigh basis of angiosperm leaves were generally higher than those of the corresponding stems. Leaves also had a higher chlorophyll content than stems. Respiration of leaves and stems of aquatic angiosperms was generally cyanide-resistant. The cyanide resistance of respiration of whole shoots of two aquatic bryophytes and an alga was lower. These results suggested that the photosynthetic tissues of aquatic plants have a considerable alternative pathway capacity. The angiosperm leaves generally showed the largest alternative path capacity. In all cases, the respiration rate of the aquatic plants studied was inhibited by SHAM alone by about 13 to 31%. These results were used for calculating the actual activities of the cytochrome and alternative pathways. These activities were generally higher in the leaves of angiosperms. The basal oxygen uptake rate of Myriophyllum spicatum leaves was greatly increased by CCCP, either in the presence or in the absence of substrates. These results suggest that respiration was limited by the adenylate system, and not by substrate availability. The increase in the respiratory rate by CCCP was due to a large increase in the activities of both the cytochrome and alternative pathways. The respiration rate of M. spicatum leaves in the presence of substrates was little inhibited by SHAM alone, but the SHAM-resistant rate (that is, the cytochrome path) was greatly stimulated by the further addition of CCCP. Similarly, the cyanide-resistant rate of O/sub 2/ uptake was also increased by the uncoupler.

  15. Cyanide-resistant respiration in photosynthetic organs of freshwater aquatic plants.

    PubMed

    Azcón-Bieto, J; Murillo, J; Peñuelas, J

    1987-07-01

    THE RATE AND SENSITIVITY TO INHIBITORS (KCN AND SALICYLHYDROXAMIC ACID[SHAM]) OF RESPIRATORY OXYGEN UPTAKE HAS BEEN INVESTIGATED IN PHOTOSYNTHETIC ORGANS OF SEVERAL FRESHWATER AQUATIC PLANT SPECIES: six angiosperms, two bryophytes, and an alga. The oxygen uptake rates on a dry weight basis of angiosperm leaves were generally higher than those of the corresponding stems. Leaves also had a higher chlorophyll content than stems. Respiration of leaves and stems of aquatic angiosperms was generally cyanide-resistant, the percentage of resistance being higher than 50% with very few exceptions. The cyanide resistance of respiration of whole shoots of two aquatic bryophytes and an alga was lower and ranged between 25 and 50%. These results suggested that the photosynthetic tissues of aquatic plants have a considerable alternative pathway capacity. The angiosperm leaves generally showed the largest alternative path capacity. In all cases, the respiration rate of the aquatic plants studied was inhibited by SHAM alone by about 13 to 31%. These results were used for calculating the actual activities of the cytochrome and alternative pathways. These activities were generally higher in the leaves of angiosperms. The basal oxygen uptake rate of Myriophyllum spicatum leaves was not stimulated by sucrose, malate or glycine in the absence of the uncoupler carbonylcyanide-m-chlorophenylhydrazone (CCCP), but was greatly increased by CCCP, either in the presence or in the absence of substrates. These results suggest that respiration was limited by the adenylate system, and not by substrate availability. The increase in the respiratory rate by CCCP was due to a large increase in the activities of both the cytochrome and alternative pathways. The respiration rate of M. spicatum leaves in the presence of substrates was little inhibited by SHAM alone, but the SHAM-resistant rate (that is, the cytochrome path) was greatly stimulated by the further addition of CCCP. Similarly, the cyanide

  16. Laboratory evaluation of Ethiopian local plant Phytolacca dodecandra extract for its toxicity effectiveness against aquatic macroinvertebrates.

    PubMed

    Karunamoorthi, K; Bishaw, D; Mulat, T

    2008-01-01

    In this study, we evaluated the toxicity effectiveness of berries crude extract of Endod [vernacular name (local native language, Amharic); Phytolacca dodecandra] against aquatic macroinvertebrates Baetidae (Mayflies) and Hydropsychidae (Caddisflies), under laboratory conditions. In Ethiopia, toxic plant, berries of Phytolacca dodecandra are being commonly used for washing clothes and to control fresh water snails. Macroinvertebrates are useful biological indicators of change in the aquatic ecosystems. The present study clearly revealed that the LC50 and LC90 values for berries crude extract of Phytolacca dodecandra against Baetidae were 181.94 and 525.78 mg/l and lethal doses (LC50 and LC90) required for Hydropsychidae were 1060.69 and 4120.4 mg/l respectively. The present investigation demonstrated that Baetidae was more susceptible than Hydropsychidae, even at shorter exposure period of 2 h. From our preliminary investigation the toxicity effectiveness of crude extracts of Phytolacca dodecandra has been clearly shown. In addition, it requires further explorations which address both the toxicity activity and the active principles that are responsible for its toxicity effectiveness. Ultimately, the release/introduction of Phytolacca dodecandra plant berries extracts into the river/streams leads to disruption of food chain in the aquatic ecosystem. Therefore, at this moment preserving the aquatic ecosystem is extremely essential and inevitable.

  17. 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.

  18. Desiccation of sediments affects assimilate transport within aquatic plants and carbon transfer to microorganisms.

    PubMed

    von Rein, I; Kayler, Z E; Premke, K; Gessler, A

    2016-11-01

    With the projected increase in drought duration and intensity in future, small water bodies, and especially the terrestrial-aquatic interfaces, will be subjected to longer dry periods with desiccation of the sediment. Drought effects on the plant-sediment microorganism carbon continuum may disrupt the tight linkage between plants and microbes which governs sediment carbon and nutrient cycling, thus having a potential negative impact on carbon sequestration of small freshwater ecosystems. However, research on drought effects on the plant-sediment carbon transfer in aquatic ecosystems is scarce. We therefore exposed two emergent aquatic macrophytes, Phragmites australis and Typha latifolia, to a month-long summer drought in a mesocosm experiment. We followed the fate of carbon from leaves to sediment microbial communities with (13) CO2 pulse labelling and microbial phospholipid-derived fatty acid (PLFA) analysis. We found that drought reduced the total amount of carbon allocated to stem tissues but did not delay the transport. We also observed an increase in accumulation of (13) C-labelled sugars in roots and found a reduced incorporation of (13) C into the PLFAs of sediment microorganisms. Drought induced a switch in plant carbon allocation priorities, where stems received less new assimilates leading to reduced starch reserves whilst roots were prioritised with new assimilates, suggesting their use for osmoregulation. There were indications that the reduced carbon transfer from roots to microorganisms was due to the reduction of microbial activity via direct drought effects rather than to a decrease in root exudation or exudate availability.

  19. Heavy metal pollution in aquatic ecosystems and its phytoremediation using wetland plants: An ecosustainable approach

    SciTech Connect

    Rai, P.K.

    2008-07-01

    This review addresses the global problem of heavy metal pollution originating from increased industrialization and urbanization and its amelioration by using wetland plants both in a microcosm as well as natural/field condition. This review mentions salient features of wetland ecosystems, their vegetation component, and the pros and cons involved in heavy metal removal. Wetland plants are preferred over other bio-agents due to their low cost, frequent abundance in aquatic ecosystems, and easy handling. Constructed wetlands proved to be effective for the abatement of heavy metal pollution from acid mine drainage; landfill leachate; thermal power; and municipal, agricultural, refinery, and chlor-alkali effluent. the physicochemical properties of wetlands provide many positive attributes for remediating heavy metals. Typha, Phragmites, Eichhornia, Azolla, Lemna, and other aquatic macrophytes are some of the potent wetland plants for heavy metal removal. Biomass disposal problem and seasonal growth of aquatic macrophytes are some limitations in the transfer of phytoremediation technology from the laboratory to the field. However, the disposed biomass of macrophytes may be used for various fruitful applications. An ecosustainable model has been developed through the author's various works, which may ameliorate some of the limitations. The creation of more areas for phytoremediation may also aid in wetlands conservation. Genetic engineering and biodiversity prospecting of endangered wetland plants are important future prospects in this regard.

  20. Enzymatic degradation of endocrine-disrupting chemicals in aquatic plants and relations to biological Fenton reaction.

    PubMed

    Reis, A R; Sakakibara, Y

    2012-01-01

    In order to evaluate the removal performance of trace phenolic endocrine-disrupting chemicals (EDCs) by aquatic plants, batch and continuous experiments were conducted using floating and submerged plants. The EDCs used in this study were bisphenol A, 2,4-dichlorophenol, 4-tert-octylphenol, pentachlorophenol, and nonylphenol. The feed concentration of each EDC was set at 100 μg/L. Continuous experiments showed that every EDC except pentachlorophenol was efficiently removed by different aquatic plants through the following reaction, catalyzed by peroxidases: EDCs+H(2)O(2)→Products+H(2)O(2). Peroxidases were able to remove phenolic EDCs in the presence of H(2)O(2) over a wide pH range (from 3 to 9). Histochemical localization of peroxidases showed that they were located in every part of the root cells, while highly concentrated zones were observed in the epidermis and in the vascular tissues. Although pentachlorophenol was not removed in the continuous treatment, it was rapidly removed by different aquatic plants when Fe(2+) was added, and this removal occurred simultaneously with the consumption of endogenous H(2)O(2). These results demonstrated the occurrence of a biological Fenton reaction and the importance of H(2)O(2) as a key endogenous substance in the treatment of EDCs and refractory toxic pollutants.

  1. Integrating nonindigenous aquatic plant control with protection of snail kite nests in Florida.

    PubMed

    Rodgers, J A; Smith, H T; Thayer, D D

    2001-07-01

    The endangered snail kite (Rostrhamus sociabilis) feeds primarily on the freshwater apple snail (Pomacea paludosa) in Florida. The nonindigenous, floating water hyacinth (Eichhornia crassipes) and water lettuce (Pistia stratiotes) impede kites from finding snails. Effective control of these aquatic plants in the littoral zone of central and south Florida lakes benefits kites by maintaining open foraging habitat. However, incidental herbicide spraying of nesting substrates result in nest collapse when kites breed in nonwoody, emergent plants [cattail (Typha spp.) and giant bulrush (Scirpus validus)] in the outer littoral zone during lower lake levels. Many endangered species recovery plans and their implementation have experienced problems due to inaction and/or noncooperation by various governmental agencies and their personnel. Herein, we describe the development and implementation of a buffer zone strategy to prevent secondary impacts from an aquatic plant control program to snail kites nesting on lakes in central and south Florida. A strategy was jointly developed by personnel of five state and federal agencies to control herbicide application near kite nesting areas during the normal breeding season. Although requiring various modifications during its implementation, this cooperative effort successfully integrated aquatic plant control objectives with snail kite conservation on Lake Okeechobee during 1988. The program was expanded the following year to lakes Kissimmee and Tohopekaliga. Since the implementation of the snail kite impact preclusion program, no nest loss was attributed to incidental herbicide applications on lakes Okeechobee, Kissimmee, and Tohopekaliga.

  2. Cascading effects of induced terrestrial plant defences on aquatic and terrestrial ecosystem function

    PubMed Central

    Jackrel, Sara L.; Wootton, J. Timothy

    2015-01-01

    Herbivores induce plants to undergo diverse processes that minimize costs to the plant, such as producing defences to deter herbivory or reallocating limited resources to inaccessible portions of the plant. Yet most plant tissue is consumed by decomposers, not herbivores, and these defensive processes aimed to deter herbivores may alter plant tissue even after detachment from the plant. All consumers value nutrients, but plants also require these nutrients for primary functions and defensive processes. We experimentally simulated herbivory with and without nutrient additions on red alder (Alnus rubra), which supplies the majority of leaf litter for many rivers in western North America. Simulated herbivory induced a defence response with cascading effects: terrestrial herbivores and aquatic decomposers fed less on leaves from stressed trees. This effect was context dependent: leaves from fertilized-only trees decomposed most rapidly while leaves from fertilized trees receiving the herbivory treatment decomposed least, suggesting plants funnelled a nutritionally valuable resource into enhanced defence. One component of the defence response was a decrease in leaf nitrogen leading to elevated carbon : nitrogen. Aquatic decomposers prefer leaves naturally low in C : N and this altered nutrient profile largely explains the lower rate of aquatic decomposition. Furthermore, terrestrial soil decomposers were unaffected by either treatment but did show a preference for local and nitrogen-rich leaves. Our study illustrates the ecological implications of terrestrial herbivory and these findings demonstrate that the effects of selection caused by terrestrial herbivory in one ecosystem can indirectly shape the structure of other ecosystems through ecological fluxes across boundaries. PMID:25788602

  3. Long-Distance Water Transport in Aquatic Plants.

    PubMed Central

    Pedersen, O.

    1993-01-01

    Acropetal mass flow of water is demonstrated in two submerged angiosperms, Lobelia dortmanna L. and Sparganium emersum Rehman by means of guttation measurements. Transpiration is absent in truly submerged plants, but the presence of guttation verifies that long-distance water transport takes place. Use of tritiated water showed that the water current arises from the roots, and the main flow of water is channeled to the youngest leaves. This was confirmed by measurement of guttation, which showed the highest rates in young leaves. Guttation rates were 10-fold larger in the youngest leaf of S. emersum (2.1 [mu]L leaf-1 h-1) compared with the youngest leaf of L. dortmanna (0.2 [mu]L leaf-1 h-1). This is probably due to profound species differences in the hydraulic conductance (2.7 x 10-17 m4 Pa-1 s-1 for S. emersum and 1.4 x 10-19 m4 Pa-1 s-1 for L. dortmanna). Estimates derived from the modified Hagen-Poiseuille equation showed that the maximum flow velocity in xylem vessels was 23 to 84 cm h-1, and the required root pressure to drive the flow was small compared to that commonly found in terrestrial plants. In S. emersum long-distance transport of water was shown to be dependent on energy conversion in the roots. The leaves ceased to guttate when the roots were cooled to 4[deg]C from the acclimatization level at 15[deg]C, whereas the guttation was stimulated when the temperature was increased to 25[deg]C. Also, the guttation rate decreased significantly when vanadate was added to the root medium. The observed water transport is probably a general phenomenon in submerged plants, where it can act as a translocation system for nutrients taken up from the rich root medium and thereby assure maximum growth. PMID:12232030

  4. Plant functions in wetland and aquatic systems: influence of intensity and capacity of soil reduction.

    PubMed

    DeLaune, R D; Pezeshki, S R

    2001-11-07

    Wetland or hydric soils, in addition to excess water and limited air-filled porosity, are characterized by anaerobic or reducing conditions. Wetland plants have developed physiological and morphological adaptations for growing under these conditions. Various methods exist for measuring plant responses to reducing conditions in wetland and aquatic environments, including assessment of radial oxygen transport, cellular enzymatic transformations, changes in root structure, and nutrient uptake. However, a gap exists in quantifying the chemical properties and reducing nature of soil environment in which plant roots are grown. The variation in reducing conditions, oxygen demand, and other associated processes that occur in wetland soils makes it difficult to truly compare the plant responses reported in the literature. This review emphasizes soil-plant interactions in wetlands, drawing attention to the importance of quantifying the intensity and capacity of reduction and/or oxygen demand in wetland soils to allow proper evaluation of wetland plant responses to such conditions.

  5. Two-flow simulation of the natural light field within a canopy of submerged aquatic plants

    NASA Technical Reports Server (NTRS)

    Ackleson, S. G.; Klemas, V.

    1986-01-01

    A two-flow model is developed to simulate a light field composed of both collimated and diffuse irradiance within natural waters containing a canopy of bottom-adhering plants. To account for the effects of submerging a canopy, the transmittance and reflectance terms associated with each plant structure (leaves, stems, fruiting bodies, etc.) are expressed as functions of the ratio of the refractive index of the plant material to the refractive index of the surrounding media and the internal transmittance of the plant stucture. Algebraic solutions to the model are shown to yield plausible physical explanations for unanticipated variations in volume reflectance spectra. The effect of bottom reflectance on the near-bottom light field is also investigated. These indicate that within light-limited submerged aquatic plant canopies, substrate reflectance may play an important role in determining the amount of light available to the plants and, therefore, canopy productivity.

  6. Transcriptome profiling of the floating-leaved aquatic plant Nymphoides peltata in response to flooding stress.

    PubMed

    Wu, Jinwei; Zhao, Hua-Bin; Yu, Dan; Xu, Xinwei

    2017-01-31

    Waterlogging or flooding is one of the most challenging abiotic stresses experienced by plants. Unlike many flooding-tolerant plants, floating-leaved aquatic plants respond actively to flooding stress by fast growth and elongation of its petioles to make leaves re-floating. However, the molecular mechanisms of this plant group responding to flood have not been investigated before. Here, we investigated the genetic basis of this adaptive response by characterizing the petiole transcriptomes of a floating-leaved species Nymphoides peltata under normal and flooding conditions. Clean reads under normal and flooding conditions with pooled sampling strategy were assembled into 124,302 unigenes. A total of 8883 unigenes were revealed to be differentially expressed between normal and flooding conditions. Among them, top ranked differentially expressed genes were mainly involved in antioxidant process, photosynthesis process and carbohydrate metabolism, including the glycolysis and a modified tricarboxylic acid cycle - alanine metabolism. Eight selected unigenes with significantly differentiated expression changes between normal and flooding conditions were validated by qRT-PCR. Among these processes, antioxidant process and glycolysis are commonly induced by waterlogging or flooding environment in plants, whereas photosynthesis and alanine metabolism are rarely occurred in other flooding-tolerant plants, suggesting the significant contributions of the two processes in the active response of N. peltata to flooding stress. Our results provide a valuable genomic resource for future studies on N. peltata and deepen our understanding of the genetic basis underlying the response to flooding stress in aquatic plants.

  7. Foraging behaviour of coypus Myocastor coypus: why do coypus consume aquatic plants?

    NASA Astrophysics Data System (ADS)

    Guichón, M. L.; Benítez, V. B.; Abba, A.; Borgnia, M.; Cassini, M. H.

    2003-12-01

    Foraging behaviour of wild coypu was studied to examine two hypotheses that had been previously proposed to explain the species' preference for aquatic plants. First, the nutritional benefit hypothesis which states that aquatic plants are more nutritional than terrestrial plants. Second, the behavioural trade-off hypothesis which states that coypus avoid foraging far from the water because of the costs associated with other types of behaviour. In order to test the nutritional benefit hypothesis, we studied the diet composition of coypus in relation to the protein content of the diet and of the plants available in the environment. Fieldwork was conducted seasonally from November 1999 to August 2000 at one study site located in the Province of Buenos Aires, east central Argentina. Behavioural observations showed that coypus remained foraging in the water and microhistological analysis of faeces indicated that their diet was principally composed of hygrophilic monocotyledons ( Lemna spp. and Eleocharis spp.) throughout the year. We did not find support for the nutritional benefit hypothesis: nutritional quality (based on nitrogen content) of hygrophilic plants was not higher than that of terrestrial plants, and seasonal changes in diet quality did not match either fluctuations in vegetation quality or proportion of hygrophilic plants in the diet. Although not directly tested, the behavioural trade-off hypothesis may explain why coypus prefer to forage in or near the water as a mechanism for reducing predation risk.

  8. Heavy metal pollution in aquatic ecosystems and its phytoremediation using wetland plants: an ecosustainable approach.

    PubMed

    Rai, Prabhat Kumar

    2008-01-01

    This review addresses the global problem of heavymetal pollution originating from increased industrialization and urbanization and its amelioration by using wetland plants both in a microcosm as well as natural/field condition. Heavymetal contamination in aquatic ecosystems due to discharge of industrial effluents may pose a serious threat to human health. Alkaline precipitation, ion exchange columns, electrochemical removal, filtration, and membrane technologies are the currently available technologies for heavy metal removal. These conventional technologies are not economical and may produce adverse impacts on aquatic ecosystems. Phytoremediation of metals is a cost-effective "green" technology based on the use of specially selected metal-accumulating plants to remove toxic metals from soils and water. Wetland plants are important tools for heavy metal removal. The Ramsar convention, one of the earlier modern global conservation treaties, was adopted at Ramsar, Iran, in 1971 and became effective in 1975. This convention emphasized the wise use of wetlands and their resources. This review mentions salient features of wetland ecosystems, their vegetation component, and the pros and cons involved in heavy metal removal. Wetland plants are preferred over other bio-agents due to their low cost, frequent abundance in aquatic ecosystems, and easy handling. The extensive rhizosphere of wetland plants provides an enriched culture zone for the microbes involved in degradation. The wetland sediment zone provides reducing conditions that are conducive to the metal removal pathway. Constructed wetlands proved to be effective for the abatement of heavymetal pollution from acid mine drainage; landfill leachate; thermal power; and municipal, agricultural, refinery, and chlor-alkali effluent. the physicochemical properties of wetlands provide many positive attributes for remediating heavy metals. Typha, Phragmites, Eichhornia, Azolla, Lemna, and other aquatic macrophytes are some

  9. Utilization of emergent aquatic plants for biomass-energy-systems development

    SciTech Connect

    Kresovich, S.; Wagner, C.K.; Scantland, D.A.; Groet, S.S.; Lawhon, W.T.

    1982-02-01

    A review was conducted of the available literature pertaining to the following aspects of emergent aquatic biomass: identification of prospective emergent plant species for management; evaluation of prospects for genetic manipulation; evaluation of biological and environmental tolerances; examination of current production technologies; determination of availability of seeds and/or other propagules, and projections for probable end-uses and products. Species identified as potential candidates for production in biomass systems include Arundo donax, Cyperus papyrus, Phragmites communis, Saccharum spontaneum, Spartina alterniflora, and Typha latifolia. If these species are to be viable candidates in biomass systems, a number of research areas must be further investigated. Points such as development of baseline yield data for managed systems, harvesting conceptualization, genetic (crop) improvement, and identification of secondary plant products require refinement. However, the potential pay-off for developing emergent aquatic systems will be significant if development is successful.

  10. Interactions between a cyanobacterial bloom ( Microcystis) and the submerged aquatic plant Ceratophyllum oryzetorum Kom.

    NASA Astrophysics Data System (ADS)

    Li, Dunhai; Li, Genbao; Chen, Wuxiong; Liu, Yongding

    2009-02-01

    In aquatic ecosystems, macrophytes and phytoplankton are main primary producers, in which macrophyte plays an important role in maintaining clear water state, while phytoplankton often dominates in turbid waterbodies. In the present study, the growth and photosynthetic activity of the submerged aquatic plant Ceratophyllum oryzetorum Kom. in different cell densities of cyanobacterial bloom are studied. The results show that the plant length and fresh mass of C. oryzetorum are promoted by low cyanobacterial cell densities. Medium and high cyanobacterial cell densities, on the contrary, act as inhibitory. Furthermore, the photosynthetic activity of C. oryzetorum is strongly inhibited by high cyanobacterial cell densities. To a certain extent, the growth of cyanobacteria is inhibited by C. oryzetorum, but no significant effect is found in this study.

  11. Effect of excess iron and copper on physiology of aquatic plant Spirodela polyrrhiza (L.) Schleid.

    PubMed

    Xing, Wei; Huang, Wenmin; Liu, Guihua

    2010-04-01

    To elucidate effect of chemical reagents addition on growth of aquatic plants in restoration of aquatic ecosystem, Spirodela polyrrhiza (L.) Schleid was used to evaluate its physiological responses to excess iron (Fe(3+)) and copper (Cu(2+)) in the study. Results showed that accumulation of iron and copper both reached maximum at 100 mg L(-1) iron or copper after 24 h short-term stress, but excess iron and copper caused plants necrosis or death and colonies disintegration as well as roots abscission at excess metal concentrations except for 1 mg L(-1) iron. Significant differences in chlorophyll fluorescence (Fv/Fm) were observed at 1-100 mg L(-1) iron or copper. The synthesis of chlorophyll and protein as well as carbohydrate and the uptake of phosphate and nitrogen were inhibited seriously by excess iron and copper. Proline content decreased with increasing iron or copper concentration, however, MDA content increased with increasing iron or copper concentration.

  12. Estimation of potential biomass resource and biogas production from aquatic plants in Argentina

    NASA Astrophysics Data System (ADS)

    Fitzsimons, R. E.; Laurino, C. N.; Vallejos, R. H.

    1982-08-01

    The use of aquatic plants in artificial lakes as a biomass source for biogas and fertilizer production through anaerobic fermentation is evaluated, and the magnitude of this resource and the potential production of biogas and fertilizer are estimated. The specific case considered is the artificial lake that will be created by the construction of Parana Medio Hydroelectric Project on the middle Parana River in Argentina. The growth of the main aquatic plant, water hyacinth, on the middle Parana River has been measured, and its conversion to methane by anaerobic fermentation is determined. It is estimated that gross methane production may be between 1.0-4.1 x 10 to the 9th cu cm/year. The fermentation residue can be used as a soil conditioner, and it is estimated production of the residue may represent between 54,900-221,400 tons of nitrogen/year, a value which is 2-8 times the present nitrogen fertilizer demand in Argentina.

  13. Aquatic Plant Control Program. Technical Report 7. Aquatic-Use Patterns for 2,4-D Dimethylamine and Integrated Control.

    DTIC Science & Technology

    Aquatic weed control, D2-4 herbicide, Acetic acid/2-4 dichlorophenoxy, Chlorine aromatic compounds, Alligatorweed, Water hyacinth, Eichhornia crassipes , Dimethylamine, Water pollution control, Pesticide residues

  14. International Symposium on the Biology and Management of Aquatic Plants. Volume 31

    DTIC Science & Technology

    1993-01-01

    Biochemists, Inc., 6120 W. Douglas Ave., Tomislav Petr - Food and Agriculture Organization, Fisheries De- Milwaukee, WI 53218. partment (FIRI), 00100 Rome...Environmental Studies, Depart- Kenneth Scott - Santee Cooper, I Riverwood Dr., Moncks Corner, ment of Chemistry , University of South Florida, Tampa, FL...secondary activities of aquatic plant manage- The California Department of Food and Agriculture, ment? This, I think, is much tougher to figure out. On the

  15. Effect of arsenic on reflectance spectra and chlorophyll fluorescence of aquatic plants.

    PubMed

    Iriel, Analia; Dundas, Gavin; Fernández Cirelli, Alicia; Lagorio, Maria G

    2015-01-01

    Arsenic pollution of groundwater is a serious problem in many regions of Latin America that causes severe risks to human health. As a consequence, non-destructive monitoring methodologies, sensitive to arsenic presence in the environment and able to perform a rapid screening of large polluted areas, are highly sought-after. Both chlorophyll - a fluorescence and reflectance of aquatic plants may be potential indicators to sense toxicity in water media. In this work, the effects of arsenic on the optical and photophysical properties of leaves of different aquatic plants (Vallisneria gigantea, Azolla filiculoides and Lemna minor) were evaluated. Reflectance spectra were recorded for the plant leaves from 300 to 2400 nm. The spectral distribution of the fluorescence was also studied and corrected for light re-absorption processes. Photosynthetic parameters (Fv/Fm and ΦPSII) were additionally calculated from the variable chlorophyll fluorescence recorded with a pulse amplitude modulated fluorometer. Fluorescence and reflectance properties for V. gigantea and A. filiculoides were sensitive to arsenic presence in contrast to the behaviour of L. minor. Observed changes in fluorescence spectra could be interpreted in terms of preferential damage in photosystem II. The quantum efficiency of photosystem II for the first two species was also affected, decreasing upon arsenic treatment. As a result of this research, V. gigantea and A. filiculoides were proposed as bioindicators of arsenic occurrence in aquatic media. Copyright © 2014 Elsevier Ltd. All rights reserved.

  16. RhizoFlowCell system reveals early effects of micropollutants on aquatic plant rhizosphere.

    PubMed

    Mynampati, Kalyan Chakravarthy; Lee, Yong Jian; Wijdeveld, Arjan; Reuben, Sheela; Samavedham, Lakshminarayanan; Kjelleberg, Staffan; Swarup, Sanjay

    2015-12-01

    In aquatic systems, one of the non-destructive ways to quantify toxicity of contaminants to plants is to monitor changes in root exudation patterns. In aquatic conditions, monitoring and quantifying such changes are currently challenging because of dilution of root exudates in water phase and lack of suitable instrumentation to measure them. Exposure to pollutants would not only change the plant exudation, but also affect the microbial communities that surround the root zone, thereby changing the metabolic profiles of the rhizosphere. This study aims at developing a device, the RhizoFlowCell, which can quantify metabolic response of plants, as well as changes in the microbial communities, to give an estimate of the stress to which the rhizosphere is exposed. The usefulness of RhizoFlowCell is demonstrated using naphthalene as a test pollutant. Results show that RhizoFlowCell system is useful in quantifying the dynamic metabolic response of aquatic rhizosphere to determine ecosystem health. Copyright © 2015 Elsevier Ltd. All rights reserved.

  17. Chromium accumulation in submerged aquatic plants treated with tannery effluent at Kanpur, India.

    PubMed

    Gupta, Kiran; Gaumat, Sumati; Mishra, Kumkum

    2011-09-01

    Aquatic macrophytes have been widely studied because of their capability of absorbing contaminants from water and their subsequent use in biomonitoring. This study presents a comparison of Cr accumulating potential of submerged aquatic plants viz Vallisneria spiralis and Hydrilla verticillata. These plants were treated with various concentrations of treated tannery effluent collected from UASB, Jajmau, Kanpur under repeated exposure in controlled laboratory conditions in order to assess their maximum bioaccumulation potential. The maximum accumulation of 385.6 and 201.6 microg g(-1) dry weight was found in roots of V. spiralis and the whole plants of H. verticillata, respectively at 100% concentration after 9th day of effluent exposure. The chlorophyll and protein content of both species decreased with increase in effluent concentration and duration. At highest concentration and duration a maximum reduction of 67.4 and 62.66% in total chlorophyll content, 9.97 and 4.66% in carotenoid content and 62.66 and 59.36% in protein content was found in V. spiralis and H. verticillata respectively. Anatomical studies in both V. spiralis and H. verticillata was carried out to assess the effects of metal accumulation within the plants. Changes in the anatomical structures of both plants exhibits the capacity of these species to act as indicator of effluent toxicity. The high accumulation potential of Cr by both plants revealed their capability to remove pollutants from effluent.

  18. Dinitrogen fixation associated with shoots of aquatic carnivorous plants: is it ecologically important?

    PubMed

    Sirová, Dagmara; Santrůček, Jiří; Adamec, Lubomír; Bárta, Jiří; Borovec, Jakub; Pech, Jiří; Owens, Sarah M; Santrůčková, Hana; Schäufele, Rudi; Storchová, Helena; Vrba, Jaroslav

    2014-07-01

    Rootless carnivorous plants of the genus Utricularia are important components of many standing waters worldwide, as well as suitable model organisms for studying plant-microbe interactions. In this study, an investigation was made of the importance of microbial dinitrogen (N2) fixation in the N acquisition of four aquatic Utricularia species and another aquatic carnivorous plant, Aldrovanda vesiculosa. 16S rRNA amplicon sequencing was used to assess the presence of micro-organisms with known ability to fix N2. Next-generation sequencing provided information on the expression of N2 fixation-associated genes. N2 fixation rates were measured following (15)N2-labelling and were used to calculate the plant assimilation rate of microbially fixed N2. Utricularia traps were confirmed as primary sites of N2 fixation, with up to 16 % of the plant-associated microbial community consisting of bacteria capable of fixing N2. Of these, rhizobia were the most abundant group. Nitrogen fixation rates increased with increasing shoot age, but never exceeded 1·3 μmol N g(-1) d. mass d(-1). Plant assimilation rates of fixed N2 were detectable and significant, but this fraction formed less than 1 % of daily plant N gain. Although trap fluid provides conditions favourable for microbial N2 fixation, levels of nif gene transcription comprised <0·01 % of the total prokaryotic transcripts. It is hypothesized that the reason for limited N2 fixation in aquatic Utricularia, despite the large potential capacity, is the high concentration of NH4-N (2·0-4·3 mg L(-1)) in the trap fluid. Resulting from fast turnover of organic detritus, it probably inhibits N2 fixation in most of the microorganisms present. Nitrogen fixation is not expected to contribute significantly to N nutrition of aquatic carnivorous plants under their typical growth conditions; however, on an annual basis the plant-microbe system can supply nitrogen in the order of hundreds of mg m(-2) into the nutrient-limited littoral

  19. Modeling plasmalemma ion transport of the aquatic plant Egeria densa.

    PubMed

    Buschmann, P; Sack, H; Köhler, A E; Dahse, I

    1996-11-01

    Fresh-water plants generate extraordinarily high electric potential differences at the plasma membrane. For a deeper understanding of the underlying transport processes a mathematical model of the electrogenic plasmalemma ion transport was developed based on experimental data mainly obtained from Egeria densa. The model uses a general nonlinear network approach and assumes coupling of the transporters via membrane potential. A proton pump, an outward-rectifying K+ channel, an inward-rectifying K+ channel, a Cl- channel and a (2H-Cl)+ symporter are considered to be elements of the system. The model takes into consideration the effects of light, external pH and ionic content of the bath medium on ion transport. As a result it does not only satisfactorily describe the membrane potential as a function of these external physiological factors but also succeeds in simulating the effects of specific inhibitors as well as I-V-curves obtained with the patch-clamp technique in the whole cell mode. The quality of the model was checked by stability and sensitivity analyses.

  20. Toxicities of oils, dispersants and dispersed oils to algae and aquatic plants: review and database value to resource sustainability

    EPA Science Inventory

    Published toxicity results are reviewed for oils, dispersants and dispersed oils and aquatic plants. The historical phytotoxicity database consists largely of results from a patchwork of research conducted after oil spills to marine waters. Toxicity information is available for ...

  1. Determination of main components and anaerobic rumen digestibility of aquatic plants in vitro using near-infrared-reflectance spectroscopy.

    PubMed

    Yue, Zheng-Bo; Zhang, Meng-Lin; Sheng, Guo-Ping; Liu, Rong-Hua; Long, Ying; Xiang, Bing-Ren; Wang, Jin; Yu, Han-Qing

    2010-04-01

    A near-infrared-reflectance (NIR) spectroscopy-based method is established to determine the main components of aquatic plants as well as their anaerobic rumen biodegradability. The developed method is more rapid and accurate compared to the conventional chemical analysis and biodegradability tests. Moisture, volatile solid, Klason lignin and ash in entire aquatic plants could be accurately predicted using this method with coefficient of determination (r(2)) values of 0.952, 0.916, 0.939 and 0.950, respectively. In addition, the anaerobic rumen biodegradability of aquatic plants, represented as biogas and methane yields, could also be predicted well. The algorithm of continuous wavelet transform for the NIR spectral data pretreatment is able to greatly enhance the robustness and predictive ability of the NIR spectral analysis. These results indicate that NIR spectroscopy could be used to predict the main components of aquatic plants and their anaerobic biodegradability.

  2. Toxicities of oils, dispersants and dispersed oils to algae and aquatic plants: review and database value to resource sustainability

    EPA Science Inventory

    Published toxicity results are reviewed for oils, dispersants and dispersed oils and aquatic plants. The historical phytotoxicity database consists largely of results from a patchwork of research conducted after oil spills to marine waters. Toxicity information is available for ...

  3. Invasion strategies in clonal aquatic plants: are phenotypic differences caused by phenotypic plasticity or local adaptation?

    PubMed

    Riis, Tenna; Lambertini, Carla; Olesen, Birgit; Clayton, John S; Brix, Hans; Sorrell, Brian K

    2010-11-01

    The successful spread of invasive plants in new environments is often linked to multiple introductions and a diverse gene pool that facilitates local adaptation to variable environmental conditions. For clonal plants, however, phenotypic plasticity may be equally important. Here the primary adaptive strategy in three non-native, clonally reproducing macrophytes (Egeria densa, Elodea canadensis and Lagarosiphon major) in New Zealand freshwaters were examined and an attempt was made to link observed differences in plant morphology to local variation in habitat conditions. Field populations with a large phenotypic variety were sampled in a range of lakes and streams with different chemical and physical properties. The phenotypic plasticity of the species before and after cultivation was studied in a common garden growth experiment, and the genetic diversity of these same populations was also quantified. For all three species, greater variation in plant characteristics was found before they were grown in standardized conditions. Moreover, field populations displayed remarkably little genetic variation and there was little interaction between habitat conditions and plant morphological characteristics. The results indicate that at the current stage of spread into New Zealand, the primary adaptive strategy of these three invasive macrophytes is phenotypic plasticity. However, while limited, the possibility that genetic diversity between populations may facilitate ecotypic differentiation in the future cannot be excluded. These results thus indicate that invasive clonal aquatic plants adapt to new introduced areas by phenotypic plasticity. Inorganic carbon, nitrogen and phosphorous were important in controlling plant size of E. canadensis and L. major, but no other relationships between plant characteristics and habitat conditions were apparent. This implies that within-species differences in plant size can be explained by local nutrient conditions. All together this

  4. Invasion strategies in clonal aquatic plants: are phenotypic differences caused by phenotypic plasticity or local adaptation?

    PubMed Central

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

    2010-01-01

    Background and Aims The successful spread of invasive plants in new environments is often linked to multiple introductions and a diverse gene pool that facilitates local adaptation to variable environmental conditions. For clonal plants, however, phenotypic plasticity may be equally important. Here the primary adaptive strategy in three non-native, clonally reproducing macrophytes (Egeria densa, Elodea canadensis and Lagarosiphon major) in New Zealand freshwaters were examined and an attempt was made to link observed differences in plant morphology to local variation in habitat conditions. Methods Field populations with a large phenotypic variety were sampled in a range of lakes and streams with different chemical and physical properties. The phenotypic plasticity of the species before and after cultivation was studied in a common garden growth experiment, and the genetic diversity of these same populations was also quantified. Key Results For all three species, greater variation in plant characteristics was found before they were grown in standardized conditions. Moreover, field populations displayed remarkably little genetic variation and there was little interaction between habitat conditions and plant morphological characteristics. Conclusions The results indicate that at the current stage of spread into New Zealand, the primary adaptive strategy of these three invasive macrophytes is phenotypic plasticity. However, while limited, the possibility that genetic diversity between populations may facilitate ecotypic differentiation in the future cannot be excluded. These results thus indicate that invasive clonal aquatic plants adapt to new introduced areas by phenotypic plasticity. Inorganic carbon, nitrogen and phosphorous were important in controlling plant size of E. canadensis and L. major, but no other relationships between plant characteristics and habitat conditions were apparent. This implies that within-species differences in plant size can be explained

  5. [Plant communities in the terrestrial-aquatic transition zone in the paramo of Chingaza, Colombia].

    PubMed

    Schmidt-Mumm, Udo; Vargas Ríos, Orlando

    2012-03-01

    Plant communities in the terrestrial-aquatic transition zone in the paramo of Chingaza, Colombia. High Andean paramo ecosystems are an important water resource for many towns, and major cities in this region. The aquatic and wetland vegetation of different paramo lakes, pond, swamps and bogs was studied according to the classical phytosociological approach, which is based on homogenous stands, but excludes any border phenomena or transitional zone. The present research aimed at determining the aquatic and wetland vegetation along different moisture gradients. A total of 89 species in 30 transects were reported, of which Crassula venezuelensis, Carex honplandii, Callitriche nubigena, Eleocharis macrostachya, Ranunculus flagelliformis, R. nubigenus, Eleocharis stenocarpa, Galium ascendens y Alopecurus aequalis were present in more than one third of the transects. Numerical classification and indicator species analysis resulted in the definition of the next 18 communities: 1) Calamagrostis effusa, 2) Sphagnum cuspidatum, 3) Cyperus rufus, 4) Eleocharis stenocarpa, 5) Carex acutata, 6) Poa annua,7) Valeriana sp., 8) Ranunculus flagelliformis, 9) Carex bonplandii, 10) Festuca andicola. 11) Muhlenbergia fustigiata, 12) Elatine paramoana, 13) Isoëtes palmeri, 14) Crassula venezuelensis, 15) Lilaeopsis macloviana, 16) Callitriche nubigena, 17) Potamogeton paramoanus and 18) Potamogeton illinoensis. The ordination of communities reveals the presence of three different aquatic-terrestrial gradients which are related to the life form structure of species that characterized the various communities. We concluded that patchiness and heterogeneity of the vegetation is mainly the result of alterations caused by human activities (burning, cattle raise and material extraction for road and dam construction).

  6. Comprehensive Cooling Water Study: Volume 5, Aquatic ecology, Savannah River Plant: Final report

    SciTech Connect

    Specht, W.L.

    1987-10-01

    The Comprehensive Cooling Water Study (CCWS) was initiated in 1983 to evaluate the environmental effects of the intake and release of cooling water on the structure and function of aquatic ecosystems at the Savannah River Plant. The initial report (Gladden et al., 1985) described the results from the first year of the study. This document is the final report and concludes the program. The report comprises eight volumes. The first is a summary of environmental effects. The other seven volumes address water quality, radionuclide and heavy metal transport, wetlands, aquatic ecology, Federally endangered species, ecology of Par Pond, and waterfowl. This report documents the results of the Aquatic Ecology Program of the Comprehensive Cooling Water Study. The purpose of the Aquatic Ecology Program was to determine the environmental impacts of cooling water intake and release on the biological communities of SRP streams and swamps and the Savannah River, and the significance of these impacts on the SRP environment. 171 refs., 132 figs., 165 tabs.

  7. Ecotoxicological assessments show sucralose and fluoxetine affect the aquatic plant, Lemna minor.

    PubMed

    Amy-Sagers, Cherisse; Reinhardt, Keith; Larson, Danelle M

    2017-04-01

    Pharmaceuticals and personal care products (PPCP) are prevalent in aquatic systems, yet the fate and impacts on aquatic plants needs quantification for many compounds. We measured and detected sucralose (an artificial sweetener), fluoxetine (an antidepressant), and other PPCP in the Portneuf River in Idaho, USA, where Lemna minor (an aquatic plant in the environment and used in ecotoxicology studies) naturally occurs. Sucralose was hypothesized to negatively affect photosynthesis and growth of L. minor because sucralose is a chlorinated molecule that may be toxic or unusable for plant metabolism. A priori hypotheses were not created for fluoxetine due to lack of previous studies examining its impacts on plants. We conducted laboratory ecotoxicological assessments for a large range of concentrations of sucralose and fluoxetine on L. minor physiology and photosynthetic function. Frond green leaf area, root length, growth rate, photosynthetic capacity, and plant carbon isotopic composition (discrimination relative to a standard; δ(13)C) were measured among treatments ranging from 0 to 15000nmol/L-sucralose and 0-323nmol/L-fluoxetine. Contrary to our predictions, sucralose significantly increased green leaf area, photosynthetic capacity, and δ (13)C of L. minor at environmentally relevant concentrations. The increase of δ (13)C from sucralose amendments and an isotope-mixing model indicated substantial sucralose uptake and assimilation within the plant. Unlike humans who cannot break down and utilize sucralose, we documented that L. minor-a mixotrophic plant-can use sucralose as a sugar substitute to increase its green leaf area and photosynthetic capacity. Fluoxetine significantly decreased L. minor root growth, daily growth rate, and asexual reproduction at 323nmol/L-fluoxetine; however, ambiguity remains regarding the mechanisms responsible and the applicability of these extreme concentrations unprecedented in the natural environment. To our knowledge, this was

  8. Impact of sugar factory effluent on the growth and biochemical characteristics of terrestrial and aquatic plants.

    PubMed

    Ayyasamy, P M; Yasodha, R; Rajakumar, S; Lakshmanaperumalsamy, P; Rahman, P K S M; Lee, Sanghoon

    2008-11-01

    The physico-chemical characteristics of sugar industry effluent were measured and some were found to be above those limits permissible in the Indian irrigation water standard. A pot study was initially conducted to study the effects of different concentrations (20%, 40%, 60%, 80% and 100%) of sugar factory effluent on seed germination, seedling growth and biochemical characteristics of green gram and maize. A similar study was also carried out using the aquatic plants, water hyacinth and water lettuce. The higher effluent concentrations (above 60%) were found to affect plant growth, but diluted effluent (up to 60%) favored seedling growth.

  9. Application of vascular aquatic plants for pollution removal, energy and food production in a biological system

    NASA Technical Reports Server (NTRS)

    Wolverton, B. C.; Barlow, R. M.; Mcdonald, R. C.

    1975-01-01

    Vascular aquatic plants such as water hyacinths (Eichhornia crassipes) (Mart.) Solms and alligator weeds (Alternanthera philoxeroides) (Mart.) Griesb., when utilized in a controlled biological system (including a regular program of harvesting to achieve maximum growth and pollution removal efficiency), may represent a remarkably efficient and inexpensive filtration and disposal system for toxic materials and sewage released into waters near urban and industrial areas. The harvested and processed plant materials are sources of energy, fertilizer, animal feed, and human food. Such a system has industrial, municipal, and agricultural applications.

  10. Growth-form and spatiality driving the functional difference of native and alien aquatic plants in Europe.

    PubMed

    Lukács, Balázs A; Vojtkó, Anna E; Mesterházy, Attila; Molnár V, Attila; Süveges, Kristóf; Végvári, Zsolt; Brusa, Guido; Cerabolini, Bruno E L

    2017-02-01

    Trait-based approaches are widely used in community ecology and invasion biology to unravel underlying mechanisms of vegetation dynamics. Although fundamental trade-offs between specific traits and invasibility are well described among terrestrial plants, little is known about their role and function in aquatic plant species. In this study, we examine the functional differences of aquatic alien and native plants stating that alien and native species differ in selected leaf traits. Our investigation is based on 60 taxa (21 alien and 39 native) collected from 22 freshwater units of Hungarian and Italian lowlands and highlands. Linear mixed models were used to investigate the effects of nativeness on four fundamental traits (leaf area, leaf dry matter content, specific leaf area, and leaf nitrogen content), while the influence of growth-form, altitude, and site were employed simultaneously. We found significantly higher values of leaf areas and significantly lower values of specific leaf areas for alien species if growth-form was included in the model as an additional predictor.We showed that the trait-based approach of autochthony can apply to aquatic environments similar to terrestrial ones, and leaf traits have relevance in explaining aquatic plant ecology whether traits are combined with growth-forms as a fixed factor. Our results confirm the importance of traits related to competitive ability in the process of aquatic plant invasions. Alien aquatic plants can be characterized as species producing soft leaves faster. We argue that the functional traits of alien aquatic plants are strongly growth-form dependent. Using the trait-based approach, we found reliable characteristics of aquatic plants related to species invasions, which might be used, for example, in conservation management.

  11. Understanding Aquaporin Transport System in Eelgrass (Zostera marina L.), an Aquatic Plant Species

    PubMed Central

    Shivaraj, S. M.; Deshmukh, Rupesh; Bhat, Javaid A.; Sonah, Humira; Bélanger, Richard R.

    2017-01-01

    Aquaporins (AQPs) are a class of integral membrane proteins involved in the transport of water and many other small solutes. The AQPs have been extensively studied in many land species obtaining water and nutrients from the soil, but their distribution and evolution have never been investigated in aquatic plant species, where solute assimilation is mostly through the leaves. In this regard, identification of AQPs in the genome of Zostera marina L. (eelgrass), an aquatic ecological model species could reveal important differences underlying solute uptake between land and aquatic species. In the present study, genome-wide analysis led to the identification of 25 AQPs belonging to four subfamilies, plasma membrane intrinsic proteins (PIPs), tonoplast intrinsic proteins (TIPs), nodulin 26-like intrinsic proteins (NIPs), small basic intrinsic proteins (SIPs) in eelgrass. As in other monocots, the XIP subfamily was found to be absent from the eelgrass genome. Further classification of subfamilies revealed a unique distribution pattern, namely the loss of the NIP2 (NIP-III) subgroup, which is known for silicon (Si) transport activity and ubiquitously present in monocot species. This finding has great importance, since the eelgrass population stability in natural niche is reported to be associated with Si concentrations in water. In addition, analysis of available RNA-seq data showed evidence of expression in 24 out of the 25 AQPs across four different tissues such as root, vegetative tissue, male flower and female flower. In contrast to land plants, higher expression of PIPs was observed in shoot compared to root tissues. This is likely explained by the unique plant architecture of eelgrass where most of the nutrients and water are absorbed by shoot rather than root tissues. Similarly, higher expression of the TIP1 and TIP5 families was observed specifically in male flowers suggesting a role in pollen maturation. This genome-wide analysis of AQP distribution, evolution

  12. Toxicity of perfluorooctane sulfonate and perfluorooctanoic acid to plants and aquatic invertebrates.

    PubMed

    Li, Mei-Hui

    2009-02-01

    Acute toxicities of perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA) were tested on four freshwater species and three plant species. PFOS was more toxic than PFOA for all species tested in this study. Similar time-response patterns of PFOS and PFOA toxicity were observed for each tested species. Values of the 48-h LC(50) of PFOS for all test species ranged from 27 to 233 mg/L and values of the 96-h LC(50) for three of the species ranged from 10 to 178 mg/L. Values of the 48-h LC(50) of PFOA for all test species ranged from 181 to 732 mg/L and values of the 96-h LC(50) for three of the species ranged from 337 to 672 mg/L. The most sensitive freshwater species to PFOS was green neon shrimp (Neocaridina denticulate) with a 96-h LC(50) of 10 mg/L. Of the aquatic organisms tested, the aquatic snail (Physa acuta) always has the highest resistance to PFOS or PFOA toxicity over each exposure period. Both PFOS and PFOA had no obvious adverse effect on seed germination for all three plant species. Five-day EC(50) of root elongation was more sensitive to LC(50) of seed germination in this study. Based on EC(10), EC(50), and NOECs, the 5-day root elongation sensitivity of test plants to both PFOS and PFOA was in the order of lettuce (Lactuca sativa) > pakchoi (Brassica rapa chinensis) > cucumber (Cucumis sativus). Based on the results of this study and other published literature, it is suggested that current PFOS and PFOA levels in freshwater may have no acute harmful ecological impact on the aquatic environment. However, more research on the long-term ecological effects of PFOS and PFOA on aquatic fauna are needed to provide important information to adequately assess ecological risk of PFOS and PFOA.

  13. Natural attenuation of weathered oil using aquatic plants in a farm in Southeast Mexico.

    PubMed

    Rivera-Cruz, María Del Carmen; Trujillo-Narcía, Antonio; Trujillo-Rivera, Eduardo A; Arias-Trinidad, Alfredo; Mendoza-López, María Remedios

    2016-09-01

    An experiment was conducted in field for three years to assess the sustainability of aquatic plants Leersia hexandra, Cyperus articulatus, and Eleocharis palustris for use in the removal of total hydrocarbons of weathered oil in four areas contaminated with 60916-119373 mg/kg of hydrocarbons. The variables evaluated were coverage of plant, dry matter, density of plant growth-promoting rhizobacteria, and the removal of total weathered oil. The variables showed statistical differences (p = 0.05) due to the effects of time and the amount of oil in the soil. The three aquatic plants survived on the farm during the 36-month evaluation. The grass L. hexandra yielded the greatest coverage of plant but was inhibited by the toxicity of the oil, which, in contrast, stimulated the coverage of C. articulatus. The rhizosphere of L. hexandra in control soil was more densely colonized by N-fixing bacteria, while the density of phosphate and potassium solubilizing rhizobacteria was stimulated by exposure to oil. C. articulatus coverage showed positive relationship with the removal of weathered oil; positive effect between rhizosphere and L. hexandra grass coverage was also identified. These results contributed to the removal of weathered oil in Gleysols flooded and affected by chronic discharges of crude oil.

  14. Recognition of pyrrolizidine alkaloid esters in the invasive aquatic plant Gymnocoronis spilanthoides (Asteraceae).

    PubMed

    Boppré, Michael; Colegate, Steven M

    2015-01-01

    The freshwater aquatic plant Gymnocoronis spilanthoides (Senegal tea plant, jazmín del bañado, Falscher Wasserfreund) is an invasive plant in many countries. Behavioural observations of pyrrolizidine alkaloid-pharmacophagous butterflies suggested the presence of pyrrolizidine alkaloids in the plant. To determine whether the attraction of the butterflies to the plant is an accurate indicator of pyrrolizidine alkaloids in G. spilanthoides. The alkaloid fraction of a methanolic extract of G. spilanthoides was analysed using HPLC with electrospray ionisation MS and MS/MS. Two HPLC approaches were used, that is, a C18 reversed-phase column with an acidic mobile phase, and a porous graphitic carbon column with a basic mobile phase. Pyrrolizidine alkaloids were confirmed, with the free base forms more prevalent than the N-oxides. The major alkaloids detected were lycopsamine and intermedine. The porous graphitic carbon HPLC column, with basic mobile phase conditions, resulted in better resolution of more pyrrolizidine alkaloids including rinderine, the heliotridine-based epimer of intermedine. Based on the MS/MS and high-resolution MS data, gymnocoronine was tentatively identified as an unusual C9 retronecine ester with 2,3-dihydroxy-2-propenylbutanoic acid. Among several minor-abundance monoester pyrrolizidines recognised, spilanthine was tentatively identified as an ester of isoretronecanol with the unusual 2-acetoxymethylbutanoic acid. The butterflies proved to be reliable indicators for the presence of pro-toxic 1,2-dehydropyrrolizidine alkaloids in G. spilanthoides, the first aquatic plant shown to produce these alkaloids. The presence of the anti-herbivory alkaloids may contribute to the plant's invasive capabilities and would certainly be a consideration in any risk assessment of deliberate utilisation of the plant. The prolific growth of the plant and the structural diversity of its pyrrolizidine alkaloids may make it ideal for investigating biosynthetic

  15. Ubiquitous water-soluble molecules in aquatic plant exudates determine specific insect attraction.

    PubMed

    Sérandour, Julien; Reynaud, Stéphane; Willison, John; Patouraux, Joëlle; Gaude, Thierry; Ravanel, Patrick; Lempérière, Guy; Raveton, Muriel

    2008-10-08

    Plants produce semio-chemicals that directly influence insect attraction and/or repulsion. Generally, this attraction is closely associated with herbivory and has been studied mainly under atmospheric conditions. On the other hand, the relationship between aquatic plants and insects has been little studied. To determine whether the roots of aquatic macrophytes release attractive chemical mixtures into the water, we studied the behaviour of mosquito larvae using olfactory experiments with root exudates. After testing the attraction on Culex and Aedes mosquito larvae, we chose to work with Coquillettidia species, which have a complex behaviour in nature and need to be attached to plant roots in order to obtain oxygen. This relationship is non-destructive and can be described as commensal behaviour. Commonly found compounds seemed to be involved in insect attraction since root exudates from different plants were all attractive. Moreover, chemical analysis allowed us to identify a certain number of commonly found, highly water-soluble, low-molecular-weight compounds, several of which (glycerol, uracil, thymine, uridine, thymidine) were able to induce attraction when tested individually but at concentrations substantially higher than those found in nature. However, our principal findings demonstrated that these compounds appeared to act synergistically, since a mixture of these five compounds attracted larvae at natural concentrations (0.7 nM glycerol, <0.5 nM uracil, 0.6 nM thymine, 2.8 nM uridine, 86 nM thymidine), much lower than those found for each compound tested individually. These results provide strong evidence that a mixture of polyols (glycerol), pyrimidines (uracil, thymine), and nucleosides (uridine, thymidine) functions as an efficient attractive signal in nature for Coquillettidia larvae. We therefore show for the first time, that such commonly found compounds may play an important role in plant-insect relationships in aquatic eco-systems.

  16. Dinitrogen fixation associated with shoots of aquatic carnivorous plants: is it ecologically important?

    PubMed Central

    Sirová, Dagmara; Šantrůček, Jiří; Adamec, Lubomír; Bárta, Jiří; Borovec, Jakub; Pech, Jiří; Owens, Sarah M.; Šantrůčková, Hana; Schäufele, Rudi; Štorchová, Helena; Vrba, Jaroslav

    2014-01-01

    Background and Aims Rootless carnivorous plants of the genus Utricularia are important components of many standing waters worldwide, as well as suitable model organisms for studying plant–microbe interactions. In this study, an investigation was made of the importance of microbial dinitrogen (N2) fixation in the N acquisition of four aquatic Utricularia species and another aquatic carnivorous plant, Aldrovanda vesiculosa. Methods 16S rRNA amplicon sequencing was used to assess the presence of micro-organisms with known ability to fix N2. Next-generation sequencing provided information on the expression of N2 fixation-associated genes. N2 fixation rates were measured following 15N2-labelling and were used to calculate the plant assimilation rate of microbially fixed N2. Key Results Utricularia traps were confirmed as primary sites of N2 fixation, with up to 16 % of the plant-associated microbial community consisting of bacteria capable of fixing N2. Of these, rhizobia were the most abundant group. Nitrogen fixation rates increased with increasing shoot age, but never exceeded 1·3 μmol N g–1 d. mass d–1. Plant assimilation rates of fixed N2 were detectable and significant, but this fraction formed less than 1 % of daily plant N gain. Although trap fluid provides conditions favourable for microbial N2 fixation, levels of nif gene transcription comprised <0·01 % of the total prokaryotic transcripts. Conclusions It is hypothesized that the reason for limited N2 fixation in aquatic Utricularia, despite the large potential capacity, is the high concentration of NH4-N (2·0–4·3 mg L–1) in the trap fluid. Resulting from fast turnover of organic detritus, it probably inhibits N2 fixation in most of the microorganisms present. Nitrogen fixation is not expected to contribute significantly to N nutrition of aquatic carnivorous plants under their typical growth conditions; however, on an annual basis the plant–microbe system can supply nitrogen in the order of

  17. Effects of triploid grass carp on aquatic plants, water quality, and public satisfaction in Washington State

    USGS Publications Warehouse

    Bonar, Scott A.; Bolding, B.; Divens, M.

    2002-01-01

    We investigated effects of triploid grass carp Ctenopharyngodon idella on aquatic macrophyte communities, water quality, and public satisfaction for 98 lakes and ponds in Washington State stocked with grass carp between 1990 and 1995. Grass carp had few noticeable effects on macrophyte communities until 19 months following stocking. After 19 months, submersed macrophytes were either completely eradicated (39% of the lakes) or not controlled (42% of the lakes) in most lakes. Intermediate control of submersed macrophytes occurred in 18% of lakes at a median stocking rate of 24 fish per vegetated surface acre. Most of the landowners interviewed (83%) were satisfied with the results of introducing grass carp. For sites where all submersed macrophytes were eradicated, average turbidity was higher (11 nephelometric turbidity units, NTU) than at sites where macrophytes were controlled to intermediate levels (4 NTU) or unaffected by grass carp grazing (5 NTU). Chlorophyll a was not significantly different between levels of macrophyte control; therefore, we concluded that most of this turbidity was abiotic and not algal. Triploid grass carp were a popular control option and effectively grazed most submersed macrophytes in Washington State. However, calculating stocking rates based on landowner estimates of aquatic plant coverage rarely resulted in intermediate levels of aquatic plant control. Additionally, the effects of particular stocking rates varied considerably. We recommend against using grass carp in Washington lakes where eradication of submersed vegetation cannot be tolerated.

  18. Endophytic fungi diversity of aquatic/riparian plants and their antifungal activity in vitro.

    PubMed

    Li, Hai-Yan; Zhao, Chun-An; Liu, Chen-Jian; Xu, Xiao-Fei

    2010-02-01

    Two hundred and fourteen endophytic fungi were isolated from 500 segments of aquatic/riparian plants Ottelia acuminata, Myriophyllum verticillatum, Equisetum arvense, Cardamine multijuga, and Impatiens chinensis. They were identified to 31 taxa in which Cladosporium, Fusarium, and Geotrichum were the dominant genera. Among all isolates, 169 (79%) were anamorphic fungi, 1 (0.5%) was an teleomorphic ascomycete and 44 (21%) were sterile mycelia. There were significant differences in the colonization frequency of endophytes between the five plant species (X~2=51.128, P<0.001, Chi-square test). The riparian plants harboured more endophytes than the submerged plants. The antifungal activity of these isolates against Fusarium solani and Phytophthora nicotianae in vitro were tested and 28 (13.1%) isolates showed antifungal activities with more than 30% growth inhibition rate against the two pathogens.

  19. Transformation of 2,4,6-trinitrotoluene by the aquatic plant Myriophyllum spicatum

    SciTech Connect

    Pavlostathis, S.G.; Comstock, K.K.; Jacobson, M.E.; Saunders, F.M.

    1998-11-01

    The ability of the aquatic plant Eurasian Watermilfoil (Myriophyllum spicatum) to transform 2,4,6-trinitrotoluene (TNT) was investigated in a series of batch assays. The TNT was added to plant cultures in single and multiple consecutive additions, at various initial concentrations, to determine its transformation kinetics, identify products formed, evaluate phytotoxic effects, and to determine the effect of light deprivation on the TNT transformation process. Rapid disappearance of TNT from the plant culture media was observed. The TNT disappearance rate was a function of both plant and TNT concentration (i.e., followed mixed, second-order kinetics). The TNT transformation occurred only in the presence of plants and was inhibited by the addition of sodium azide. Phytotoxicity leading to plant chlorosis was observed in batch plant cultures with an initial TNT concentration above 5.9 {micro}M. Reductive transformation of TNT to aminodinitrotoluenes and lower levels of hydroxylaminodinitrotoluene and diaminonitrotoluenes detected in the plant culture media accounted for less than 10 to 20% of the total TNT mass added. Extraction of plant material at the end of batch incubations when all TNT was depleted from the media yielded low levels of TNT and aminodinitrotoluenes and accounted for only 3.4% of the initially added TNT mass. Light deprivation decreased both the rate and extent of the reductive transformation of TNT.

  20. Do submerged aquatic plants influence their periphyton to enhance the growth and reproduction of invertebrate mutualists?

    PubMed

    Jones, J I; Young, J O; Haynes, G M; Moss, B; Eaton, J W; Hardwick, K J

    1999-08-01

    It has been suggested that submerged aquatic plants can influence the nutritional quality of the periphyton which grows on their surfaces, making it more nutritious for grazing invertebrates, particularly snails. In return, these grazers might preferentially feed on the periphyton and clear the plants of a potential competitor, with the plants and grazers both gaining from this mutualistic relationship. A highly replicated experiment was conducted, in which the nature of the plant (isoetid and elodeid types compared with similar-shaped inert substrata), the nutrient loading, and the influence of periphyton grazers (the bladder snail, Physa fontinalis) of similar size and history were controlled. Plant growth and survival significantly increased in the presence of the periphyton grazer. Whilst the presence of the grazers had the largest influence on periphyton abundance, nutrient availability and plant type also had effects. Plant type had little influence on the nutritional quality of the periphyton measured as carbohydrate, protein and C:N. Effects of treatment on snail growth, and the timing and extent of snail reproduction disappeared when they were compared with the quantity of periphyton available. There was no evidence of enhanced grazer success in the presence of the live plants compared with inert substrata. Although submerged plants affect the growth and reproduction of the grazers which feed on their surfaces, through differences in the amount of periphyton which grows there, we found no evidence that they manipulate the periphyton to encourage such grazers.

  1. Photoacoustic analysis of the ultrasonic irradiation effect in the photosynthetic activity in aquatic lirium plants.

    PubMed

    Calderón, A; Cardona, A; Nogal, U; Juárez Gracia, A G; Marín, E; Muñoz Hernández, R A

    2014-01-01

    We report, the application of the photoacoustic technique for monitoring the photosynthesis evolution in aquatic lirium (Eichhornia Crassipes), before and after it was exposed to ultrasonic irradiations. We obtained the disappearance of the phototobaric contribution in the PA signal measured for the irradiated samples with ultrasound of 17 kHz, and therefore of a possible damage in the centers producing the photosynthesis, due to the irradiation. These results show the utility of the ultrasonic irradiation, as well as, of the photosynthesis monitoring by means of the photoacoustic technique, for the elaboration and establishment of methodologies in the control of this aquatic plant, whose propagation causes many consequences extremely unfavorable for the environment, as well as for the diverse human activities that are developed in the bodies of water in the tropical and sub-tropical regions of the world.

  2. Estimation of potential biomass resource and biogas production from aquatic plants in Argentina

    SciTech Connect

    Fitzsimons, R.E.; Laurino, C.N.; Vallejos, R.H.

    1982-01-01

    The Argentine government's Agua y Energia Electrica is planning to construct a hydroelectric power-generation facility on the middle Parana River, which is already heavily infested with aquatic weeds such as water hyacinth. These species will probably proliferate in the lakes that will be formed by the power project and perhaps seriously interfere with the facility. As a solution to this problem, Argentine biochemists propose mechanical harvesting and anaerobic fermentation of the aquatic plants to produce biogas and fertilizer. According to an evaluation of this potential resource, gross methane production could reach 37-153 billion CF (1.0-4.1 billion m/sup 3/)/yr, and the digested residue could provide 60,500-244,000 tons (54,900-221,400 metric tons)/yr of nitrogen, which represents 2-8 times Argentina's current nitrogen fertilizer demand.

  3. [Ammonia-oxidizing bacteria community composition at the root zones of aquatic plants after ecological restoration].

    PubMed

    Xing, Peng; Kong, Fan-xiang; Chen, Kai-ning; Chen, Mei-jun; Wu, Xiao-dong

    2008-08-01

    To investigate the effects of aquatic plants on ammonia-oxidizing bacteria (AOB) at their root zones, four species of aquatic plants were selected, Phragmites communis, Typha angustifolia L., Potamogeton crispus L., and Limnanthemun nymphoides, which were widely used in ecological restorations. AOB in the samples were enumerated by most-probable-number (MPN) method. Nested polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) procedures were performed with ammonia oxidizer-selective primers. Main DGGE bands were excised from the gel and sequenced for phylogenetic affiliation. Results indicate that AOB densities are always higher at the root zones of emergent plants (Phragmites communis 2.8 x 10(5) cells/g and Typha angustifolia L.4.3 x 10(5) cells/g) than those of submerged and floating-leaved plant (Potamogeton crispus L. 9.3 x 10(4) cells/g and Limnanthemun nymphoides 7.7 x 10(4) cells/g). At the root zones, the oxidation-reduction potential is above zero and NH4+ concentration is lower than it in the bare surface sediment. Fourteen major bands were recovered from the DGGE gel, re-amplified and sequenced. Although the identified bands have their respective similar sequences in GenBank, most of them are related to Nitrosomonas-like. This type of bacteria would play an important role of nitrogen cycle in lake sediment after ecological restoration.

  4. A comparative study of the modeled effects of atrazine on aquatic plant communities in midwestern streams.

    PubMed

    Nair, Shyam K; Bartell, Steven M; Brain, Richard A

    2015-11-01

    Potential effects of atrazine on the nontarget aquatic plants characteristic of lower-order streams in the Midwestern United States were previously assessed using the Comprehensive Aquatic System Model (CASMATZ ). Another similar bioenergetics-based, mechanistic model, AQUATOX, was examined in the present study, with 3 objectives: 1) to develop an AQUATOX model simulation similar to the CASMATZ model reference simulation in describing temporal patterns of biomass production by modeled plant populations, 2) to examine the implications of the different approaches used by the models in deriving plant community-based levels of concern (LOCs) for atrazine, and 3) to determine the feasibility of implementing alternative ecological models to assess ecological impacts of atrazine on lower-order Midwestern streams. The results of the present comparative modeling study demonstrated that a similar reference simulation to that from the CASMATZ model could be developed using the AQUATOX model. It was also determined that development of LOCs and identification of streams with exposures in excess of the LOCs were feasible with the AQUATOX model. Compared with the CASMATZ model results, however, the AQUATOX model consistently produced higher estimates of LOCs and generated non-monotonic variations of atrazine effects with increasing exposures. The results of the present study suggest an opportunity for harmonizing the treatments of toxicity and toxicity parameter estimation in the CASMATZ and the AQUATOX models. Both models appear useful in characterizing the potential impacts of atrazine on nontarget aquatic plant populations in lower-order Midwestern streams. The present model comparison also suggests that, with appropriate parameterization, these process-based models can be used to assess the potential effects of other xenobiotics on stream ecosystems. © 2015 SETAC.

  5. The aquatic toxicity and chemical forms of coke plant effluent cyanide -- Implications for discharge limits

    SciTech Connect

    Garibay, R.; Rupnow, M.; Godwin-Saad, E.; Hall, S.

    1995-12-31

    Cyanide is present in treated cokemaking process waters at concentrations as high as 8.0 mg/L. In assessing options for managing the discharge of a treated effluent, the development and implementation of discharge limits for cyanide became a critical issue. A study was initiated to evaluate possible alternatives to cyanide permit limits at the US Steel Gary Works Facility. The objectives of the study were to: (1) evaluation the forms of cyanide present in coke plant effluent; (2) determine whether these forms of cyanide are toxic to selected aquatic organisms; (3) compare the aquatic toxicity of various chemical forms of cyanide; (4) identify if the receiving water modifies cyanide bioavailability; and (5) confirm, with respect to water quality-based effluent limits, an appropriate analytical method for monitoring cyanide in a coke plant effluent. The results of aquatic toxicity tests and corresponding analytical data are presented. Toxicity tests were conducted with various pure chemical forms of cyanide as well as whole coke plant effluent (generated from a pilot-scale treatment system). Test species included the fathead minnow (Pimephales promelas), rainbow trout (Oncorhynchus mykiss), Ceriodaphnia dubia (C. dubia) and Daphnia magna (D. magna). Analytical measurements for cyanide included total, weak acid dissociable, diffusible cyanide and selected metal species of cyanide. The findings presented by the paper are relevant with respect to the application of cyanide water quality criteria for a coke plant effluent discharge, the translation of these water quality-based effluent limits to permit limits, and methods for compliance monitoring for cyanide.

  6. Functional trait composition of aquatic plants can serve to disentangle multiple interacting stressors in lowland streams.

    PubMed

    Baattrup-Pedersen, Annette; Göthe, Emma; Riis, Tenna; O'Hare, Matthew T

    2016-02-01

    Historically, close attention has been paid to negative impacts associated with nutrient loads to streams and rivers, but today hydromorphological alterations are considered increasingly implicated when lowland streams do not achieve good ecological status. Here, we explore if trait-abundance patterns of aquatic plants change along gradients in hydromorphological degradation and eutrophication in lowland stream sites located in Denmark. Specifically, we hypothesised that: i) changes in trait-abundance patterns occur along gradients in hydromorphological degradation and ii) trait-abundance patterns can serve to disentangle effects of eutrophication and hydromorphological degradation in lowland streams reflecting that the mechanisms behind changes differ. We used monitoring data from a total of 147 stream reaches with combined data on aquatic plant species abundance, catchment land use, hydromorphological alterations (i.e. planform, cross section, weed cutting) and water chemistry parameters. Traits related to life form, dispersal, reproduction and survival together with ecological preference values for nutrients and light (Ellenberg N and L) were allocated to 41 species representing 79% of the total species pool. We found clear evidence that habitat degradation (hydromorphological alterations and eutrophication) mediated selective changes in the trait-abundance patterns of the plant community. Specific traits could distinguish hydromorphological degradation (free-floating, surface; anchored floating leaves; anchored heterophylly) from eutrophication (free-floating, submerged; leaf area). We provide a conceptual framework for interpretation of how eutrophication and hydromorphological degradation interact and how this is reflected in trait-abundance patterns in aquatic plant communities in lowland streams. Our findings support the merit of trait-based approaches in biomonitoring as they shed light on mechanisms controlling structural changes under environmental

  7. Effects of acidification on metal accumulation by aquatic plants and invertebrates. 2. Wetlands, ponds and small lakes

    USGS Publications Warehouse

    Albers, P.H.; Camardese, M.B.

    1993-01-01

    High concentrations of trace metals in the water of low-pH lakes and streams could result in elevated amounts of metals within or adsorbed to aquatic plants and, possibly, invertebrates. Concentrations of Al, Cd, Ca, Cu, Fe, Pb, Mg, Mn, Hg, Ni, P, and Zn were compared in water, plants, and aquatic invertebrates of wetlands, ponds, and small lakes in Maryland and Maine. The accumulation of metals by aquatic plants and insects and the concentrations of metals in water were not greatly affected by pH. None of the metal concentrations significantly correlated with metals in insects. Plant metal concentrations poorly correlated with metal concentrations in water. Concentrations of metals exceeded acceptable dietary levels more frequently in plants than in invertebrates. Concerns about metal toxicity in birds that feed on invertebrates and plants from acidified waters seem to be unwarranted. Positive correlations among pH, Ca in water, Ca in insects, and Ca in plants imply that acidification can reduce the Ca content of aquatic biota. Aquatic insects were low in Ca, but crayfishes and snails, which are adversely affected by low pH, were very high. A concern for waterfowl is Ca deprivation from decreased Ca availability in low-pH wetlands, ponds, and small lakes.

  8. The Dynamics of Flow and Three-dimensional Motion Around a Morphologically Complex Aquatic Plant

    NASA Astrophysics Data System (ADS)

    Boothroyd, R.; Hardy, R. J.; Warburton, J.; Marjoribanks, T.

    2016-12-01

    Aquatic vegetation has a significant impact on the hydraulic functioning of river systems. The morphology of an individual plant can influence the mean and turbulent properties of the flow, and the plant posture reconfigures to minimise drag. We report findings from a flume and numerical experiment investigating the dynamics of motion and three-dimensional flow around an isolated Hebe odora plant over a range of flow conditions. In the flume experiment, a high definition video camera recorded plant motion dynamics and three-dimensional velocity profiles were measured using an acoustic Doppler velocimeter. By producing a binary image of the plant in each frame, the plant dynamics can be quantified. Zones of greatest plant motion are on the upper and leeward sides of the plant. With increasing flow the plant is compressed and deflected downwards by up to 18% of the unstressed height. Plant tip motions are tracked and shown to lengthen with increasing flow, transitioning from horizontally dominated to vertically dominated motion. The plant acts as a porous blockage to flow, producing spatially heterogeneous downstream velocity fields with the measured wake length decreasing by 20% with increasing flow. These measurements are then used as boundary conditions and to validate a computational fluid dynamics (CFD) model. By explicitly accounting for the time-averaged plant posture, good agreement is found between flume measurements and model predictions. The flow structures demonstrate characteristics of a junction vortex system, with plant shear layer turbulence dominated by Kelvin-Helmholtz and Görtler-type vortices generated through shear instability. With increasing flow, drag coefficients decrease by up to 8%, from 1.45 to 1.34. This is equivalent to a change in the Manning's n term from 0.086 to 0.078.

  9. Plant-microbe interaction in aquatic system and their role in the management of water quality: a review

    NASA Astrophysics Data System (ADS)

    Srivastava, Jatin K.; Chandra, Harish; Kalra, Swinder J. S.; Mishra, Pratibha; Khan, Hena; Yadav, Poonam

    2016-04-01

    Microbial assemblage as biofilm around the aquatic plant forms a firm association that largely depends upon the mutual supplies of nutrients, e.g., microbes interact with plants in an aquatic system most likely for organic carbon and oxygen, whereas plants receive defensive immunity and mineral exchange. Apart from the mutual benefits, plant-microbe interactions also influence the water quality especially at rhizosphere providing inherent ability to the aquatic system for the mitigation of pollution from the water column. The review presents and in-depth information along with certain research advancements made in the field of ecological and bio/chemical aspects of plant-microbe interactions and the underlying potential to improve water quality.

  10. Plant-microbe interaction in aquatic system and their role in the management of water quality: a review

    NASA Astrophysics Data System (ADS)

    Srivastava, Jatin K.; Chandra, Harish; Kalra, Swinder J. S.; Mishra, Pratibha; Khan, Hena; Yadav, Poonam

    2017-06-01

    Microbial assemblage as biofilm around the aquatic plant forms a firm association that largely depends upon the mutual supplies of nutrients, e.g., microbes interact with plants in an aquatic system most likely for organic carbon and oxygen, whereas plants receive defensive immunity and mineral exchange. Apart from the mutual benefits, plant-microbe interactions also influence the water quality especially at rhizosphere providing inherent ability to the aquatic system for the mitigation of pollution from the water column. The review presents and in-depth information along with certain research advancements made in the field of ecological and bio/chemical aspects of plant-microbe interactions and the underlying potential to improve water quality.

  11. Aquatic plant community invasibility and scale-dependent patterns in native and invasive species richness.

    PubMed

    Capers, Robert S; Selsky, Roslyn; Bugbee, Gregory J; White, Jason C

    2007-12-01

    Invasive species richness often is negatively correlated with native species richness at the small spatial scale of sampling plots, but positively correlated in larger areas. The pattern at small scales has been interpreted as evidence that native plants can competitively exclude invasive species. Large-scale patterns have been understood to result from environmental heterogeneity, among other causes. We investigated species richness patterns among submerged and floating-leaved aquatic plants (87 native species and eight invasives) in 103 temperate lakes in Connecticut (northeastern USA) and found neither a consistently negative relationship at small (3-m2) scales, nor a positive relationship at large scales. Native species richness at sampling locations was uncorrelated with invasive species richness in 37 of the 60 lakes where invasive plants occurred; richness was negatively correlated in 16 lakes and positively correlated in seven. No correlation between native and invasive species richness was found at larger spatial scales (whole lakes and counties). Increases in richness with area were uncorrelated with abiotic heterogeneity. Logistic regression showed that the probability of occurrence of five invasive species increased in sampling locations (3 m2, n = 2980 samples) where native plants occurred, indicating that native plant species richness provided no resistance against invasion. However, the probability of three invasive species' occurrence declined as native plant density increased, indicating that density, if not species richness, provided some resistance with these species. Density had no effect on occurrence of three other invasive species. Based on these results, native species may resist invasion at small spatial scales only in communities where density is high (i.e., in communities where competition among individuals contributes to community structure). Most hydrophyte communities, however, appear to be maintained in a nonequilibrial condition by

  12. Fast method for the simultaneous determination of monomethylmercury and inorganic mercury in rice and aquatic plants.

    PubMed

    Jiménez-Moreno, María; Lominchar, Miguel Ángel; Sierra, María José; Millán, Rocío; Martín-Doimeadios, Rosa Carmen Rodríguez

    2018-01-01

    Recent investigations revealed that monomethylmercury (MMHg) can be absorbed and accumulated by plants, i.e. rice crops, thus becoming an important route of human exposure to MMHg through diet. The increasing concern about this fact makes that appropriate analytical methods for Hg speciation in these samples are urgently required. Therefore, the aim of this work has been the development of a fast and sensitive method which enables the simultaneous determination of MMHg and inorganic Hg in rice and aquatic plants. The proposed methodology is based on the extraction of Hg species by closed-vessel microwave heating, subsequent derivatization by ethylation and analysis by gas chromatography coupled to atomic fluorescence detection via pyrolysis (GC-pyro-AFS). A careful optimization of the extraction, using both acid (6N HNO3) and alkaline (tetramethylammonium hydroxide, TMAH) extractants, and derivatization conditions has been carried out. Spiked and unspiked aquatic plants (Typha domingensis) and CRMs certified for Total-Hg (BCR-60, BCR-482 and NCS ZC73027, corresponding to aquatic plant, lichen and rice, respectively) have been used. Under the final optimized conditions the simultaneous determination of MMHg and inorganic Hg can be carried out in less than 40min with no tedious clean-up steps. Quantitative recoveries (from 92% to 101%) were obtained in aquatic plants (Typha domingensis) and CRMs spiked with known concentrations of MMHg. For unspiked BCR-60 and BCR-482, no statistically significant differences (p=0.05) were found in Total-Hg concentrations between those obtained by the sum of species and the certified values for both acid and alkaline extraction. For the analysis of low Hg polluted samples, an additional preconcentration step by evaporation under nitrogen stream was required but adequate blanks were only obtained for acid extraction. Detection limits in the low ng/g range (0.7-1.0ng/g) were consequently achieved for both Hg species in the case of acid

  13. Global searches for microalgae and aquatic plants that can eliminate radioactive cesium, iodine and strontium from the radio-polluted aquatic environment: a bioremediation strategy.

    PubMed

    Fukuda, Shin-Ya; Iwamoto, Koji; Atsumi, Mika; Yokoyama, Akiko; Nakayama, Takeshi; Ishida, Ken-Ichiro; Inouye, Isao; Shiraiwa, Yoshihiro

    2014-01-01

    The Fukushima 1 Nuclear Power Plant accident in March 2011 released an enormously high level of radionuclides into the environment, a total estimation of 6.3 × 10¹⁷ Bq represented by mainly radioactive Cs, Sr, and I. Because these radionuclides are biophilic, an urgent risk has arisen due to biological intake and subsequent food web contamination in the ecosystem. Thus, urgent elimination of radionuclides from the environment is necessary to prevent substantial radiopollution of organisms. In this study, we selected microalgae and aquatic plants that can efficiently eliminate these radionuclides from the environment. The ability of aquatic plants and algae was assessed by determining the elimination rate of radioactive Cs, Sr and I from culture medium and the accumulation capacity of radionuclides into single cells or whole bodies. Among 188 strains examined from microalgae, aquatic plants and unidentified algal species, we identified six, three and eight strains that can accumulate high levels of radioactive Cs, Sr and I from the medium, respectively. Notably, a novel eustigmatophycean unicellular algal strain, nak 9, showed the highest ability to eliminate radioactive Cs from the medium by cellular accumulation. Our results provide an important strategy for decreasing radiopollution in Fukushima area.

  14. Acoustic effects during photosynthesis of aquatic plants enable new research opportunities

    PubMed Central

    Kratochvil, Helmut G.; Pollirer, Michael

    2017-01-01

    Measurements of photosynthetic processes in hydrophytes mostly involve photosynthometers, which capture the escaping gas for subsequent analysis The most common method to detect changes in the rate of photosynthetic processes is to count the series of escaping gas bubbles. The emerging bubbles are either simply counted or they are recorded using light barriers, which is very difficult because of their small size and often varying ascent rate. The gas bubbles generated during photosynthesis by aquatic plants produce distinctive sound pulses when leaving the plants. These acoustic side effects enable completely new and highly accurate measurements. The frequency and reaction time changes of the pulses caused by external influences are therefore accurately detectable. The precise time measurements enable registering and evaluating the curves as reactions to changes in physical or chemical environmental conditions. We show that such acoustic analyses open completely new research opportunities for plant physiology. PMID:28291222

  15. Acoustic effects during photosynthesis of aquatic plants enable new research opportunities.

    PubMed

    Kratochvil, Helmut G; Pollirer, Michael

    2017-03-14

    Measurements of photosynthetic processes in hydrophytes mostly involve photosynthometers, which capture the escaping gas for subsequent analysis The most common method to detect changes in the rate of photosynthetic processes is to count the series of escaping gas bubbles. The emerging bubbles are either simply counted or they are recorded using light barriers, which is very difficult because of their small size and often varying ascent rate. The gas bubbles generated during photosynthesis by aquatic plants produce distinctive sound pulses when leaving the plants. These acoustic side effects enable completely new and highly accurate measurements. The frequency and reaction time changes of the pulses caused by external influences are therefore accurately detectable. The precise time measurements enable registering and evaluating the curves as reactions to changes in physical or chemical environmental conditions. We show that such acoustic analyses open completely new research opportunities for plant physiology.

  16. Fate of psychoactive compounds in wastewater treatment plant and the possibility of their degradation using aquatic plants.

    PubMed

    Mackuľak, Tomáš; Mosný, Michal; Škubák, Jaroslav; Grabic, Roman; Birošová, Lucia

    2015-03-01

    In this study we analyzed and characterized 29 psychoactive remedies, illicit drugs and their metabolites in single stages of wastewater treatment plants in the capital city of Slovakia. Psychoactive compounds were present within all stages, and tramadol was detected at a very high concentration (706 ng/L). Significant decreases of codeine, THC-COOH, cocaine and buprenorphine concentration were observed in the biological stage. Consequently, we were interested in the possibility of alternative tertiary post-treatment of effluent water with the following aquatic plants: Cabomba caroliniana, Limnophila sessiliflora, Egeria najas and Iris pseudacorus. The most effective plant for tertiary cleansing was I. pseudacorus which demonstrated the best pharmaceutical removal capacity. After 48 h codeine and citalopram was removed with 87% efficiency. After 96 h were all analyzed compounds were eliminated with efficiencies above 58%. Copyright © 2015 Elsevier B.V. All rights reserved.

  17. Ecological effect and risk towards aquatic plants induced by perfluoroalkyl substances: Bridging natural to culturing flora.

    PubMed

    Zhou, Yunqiao; Wang, Tieyu; Jiang, Zhaoze; Kong, Xiaoxiao; Li, Qifeng; Sun, Yajun; Wang, Pei; Liu, Zhaoyang

    2017-01-01

    In the present study, the concentrations and proportions of perfluoroalkyl substances (PFASs) in water and sediments (in different seasons) from the Qing River were investigated. The highest concentration of PFASs in water (207.59 ng L(-1)) was found in summer. The composition of PFASs in water changed with time, perfluorobutane sulfonate (PFBS) was the predominant compound in spring and summer, while long-chain PFASs, perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS), started to increase in autumn and winter. The PFASs concentration in sediments ranged from 0.96 to 4.05 ng g(-1) dw. The proportion of long-chain PFASs was higher than that of short-chain PFASs in sediments, the dominant component in sediments was PFOA with a contribution of 24.6-75.4% to total PFASs in sediments, followed by PFOS. The concentrations of PFASs in roots of emergent plants were relatively higher than those in submerged plants. However, the translocation effect of PFASs was not remarkable. Bioaccumulation factors (BAFs) of the aquatic plants indicated the absorption of PFASs were effective. BAFs in submerged plants basically increased with increasing chain length accordingly. In general, aquatic plants had the absorption preference for long-chain PFASs, especially PFOS, which was the predominant compounds in both submerged and emergent plants. Based on the results above, hornworts were selected to be cultivated indoor in the nutrient solution spiked gradient concentrations of PFOS to assess the general ecological risk. The results revealed that hornworts were resistant to PFOS and might be used as remediation flora to eliminate PFOS contamination. Copyright © 2016 Elsevier Ltd. All rights reserved.

  18. Effect of evapotranspiration on the salinity of wastewater treated by aquatic plants.

    PubMed

    Kirzhner, F; Zimmels, Y; Gafni, A

    2008-01-01

    The shortage of good quality water resources is becoming an important issue in arid and semi-arid zones. Irrigation systems must be developed that are capable of delivering low quality wastewater while taking into account environmental and health requirements. For this reason, the availability of water resources of marginal quality, such as desalinated wastewater, can be a significant contribution to the water supply. We investigated changes in salinity, in conjunction with evaporation kinetics of treated wastewater by aquatic plants. These plants enhance the removal of pollutants by consuming them in the form of plant nutrients and through the microbial activity on their roots. In particular, this treatment applies to urban and agricultural sewage, where treatment units of different sizes can be applied at the pollution source while acting as green environments. In these treatment units, increased salinity due to effect of evapotranspiration (ET) must be managed. The rates of evaporation (E) from the free water surface and transpiration (T) from the plants were determined under field and laboratory conditions. To this end, batch experiments were performed with floating and emergent aquatic plants. After 4 days in the presence of floating plants, the biochemical oxygen demand (BOD) decreased from its 100-110 mg L(-1) initial value down to 30-40 mg L(-1) (65% to 70% removal), concurrent with a 2% to 5% increase in the chlorides level, and 5% to 8% in the electroconductivity. The ET rates were found to be a significant factor in the water balance governing the treatment process. The results of this work provide guidelines for recommended wastewater treatment times that safeguard against undesirable rises in salinity, yet with marginal change in parameters such as BOD. The change of salinity is shown to be relatively minor in the first days of treatment where the change in BOD is faster, whereas in the following days the picture is reversed. This result indicates the

  19. The avoidance strategy of environmental constraints by an aquatic plant Potamogeton alpinus in running waters.

    PubMed

    Robionek, Alicja; Banaś, Krzysztof; Chmara, Rafał; Szmeja, Józef

    2015-08-01

    Aquatic plants anchored in streams are under pressure from various constraints linked to the water flow and display strategies to prevent their damage or destruction. We assume that the responses of aquatic plants to fast-water flow are a manifestation of a trade-off consisting in either maximizing the resistance to damage (tolerance strategy) in minimizing the hydrodynamic forces (avoidance strategy), or both. Our main hypothesis was that Potamogeton alpinus demonstrate the avoidance strategy. We analyzed architecture traits of the modules of this clonal plant from slow- and fast-flowing streams. In fast-flowing waters, the avoidance strategy of P. alpinus is reflected by the following: (1) the presence of floating leaves that stabilize the vertical position of the stem and protect the inflorescence against immersion; (2) elongation of submerged leaves (weakens the pressure of water); and (3) shoot diameter reduction and increase in shoot density (weakens the pressure of water, increases shoot elasticity), and by contrast in slow-water flow include the following: (4) the absence of floating leaves in high intensity of light (avoiding unnecessary outlays on a redundant organ); (5) the presence of floating leaves in low intensity of light (avoidance of stress caused by an insufficient assimilation area of submerged leaves).

  20. Distribution of metals in aquatic edible plants: Trapa natans (Roxb.) Makino and Ipomoea aquatica Forsk.

    PubMed

    Rai, U N; Sinha, S

    2001-09-01

    Most of the water bodies being used for the cultivation of edible aquatic plants (Trapa natans and Ipomoea aquatica) in Lucknow district, U.P., India, were found to be contaminated with a variety of toxic metals (Fe, Cu, Cr, Mn and Pb). The concentration of metals Cr, Pb and Fe in water was much higher than recommended permissible limits of WHO (1995). The edible parts of these plants bioconcentrated metals from their surrounding water significantly. Therefore, the present study was planned to assess the metal concentration in edible part of plants which was collected from various water bodies used for cultivation of these crops. Despite varying levels of metals found in various fruit parts of T. natans, the metal accumulation in kernel was alarming. However, metal content decreased significantly in various parts after boiling the fruit. Similarly, I. aquatica also accumulated significantly higher amounts of these metals in leaves, however the metal accumulating potential varied considerably depending upon level of metal contamination in the water body in which they were growing. The importance of these findings in the exploitation of these aquatic crops to meet the demand of food and health perspectives for human beings is highlighted.

  1. Compiled data on the vascular aquatic plant program, 1975 - 1977. [for sewage lagoon

    NASA Technical Reports Server (NTRS)

    Wolverton, B. C.; Mcdonald, R.

    1977-01-01

    The performance of a single cell, facultative sewage lagoon was significantly improved with the introduction of vascular aquatic plants. Water hyacinth (Eichhornia crassipes) was the dominant plant from April to November; duckweed (Lemna spp.) and (Spirodela spp.) flourished from December to March. This 2 ha lagoon received approximately 475 cu m/day of untreated sewage and has a variable COD sub 5 loading rate of 22-30 kg/ha/day. During the first 14 months of operation with aquatic plants, the average influent BOD sub 5 was reduced by 95% from 110 mg/l to an average of 5 mg/l in the effluent. The average influent suspended solids were reduced by 90% from 97 mg/l to 10 mg/l in the effluent. Significant reductions in nitrogen and phosphorus were effected. The monthly kjeldahl nitrogen for influent and effluent averaged 12.0 and 3.4 mg/l, respectively, a reduction of 72%. The total phosphorus was reduced on an average of 56% from 3.7 mg/l influent to 1.6 mg/l effluent.

  2. AQUATIC PLANT SPECIATION AFFECTED BY DIVERSIFYING SELECTION OF ORGANELLE DNA REGIONS(1).

    PubMed

    Kato, Syou; Misawa, Kazuharu; Takahashi, Fumio; Sakayama, Hidetoshi; Sano, Satomi; Kosuge, Keiko; Kasai, Fumie; Watanabe, Makoto M; Tanaka, Jiro; Nozaki, Hisayoshi

    2011-10-01

    Many of the genes that control photosynthesis are carried in the chloroplast. These genes differ among species. However, evidence has yet to be reported revealing the involvement of organelle genes in the initial stages of plant speciation. To elucidate the molecular basis of aquatic plant speciation, we focused on the unique plant species Chara braunii C. C. Gmel. that inhabits both shallow and deep freshwater habitats and exhibits habitat-based dimorphism of chloroplast DNA (cpDNA). Here, we examined the "shallow" and "deep" subpopulations of C. braunii using two nuclear DNA (nDNA) markers and cpDNA. Genetic differentiation between the two subpopulations was measured in both nDNA and cpDNA regions, although phylogenetic analyses suggested nuclear gene flow between subpopulations. Neutrality tests based on Tajima's D demonstrated diversifying selection acting on organelle DNA regions. Furthermore, both "shallow" and "deep" haplotypes of cpDNA detected in cultures originating from bottom soils of three deep environments suggested that migration of oospores (dormant zygotes) between the two habitats occurs irrespective of the complete habitat-based dimorphism of cpDNA from field-collected vegetative thalli. Therefore, the two subpopulations are highly selected by their different aquatic habitats and show prezygotic isolation, which represents an initial process of speciation affected by ecologically based divergent selection of organelle genes.

  3. The avoidance strategy of environmental constraints by an aquatic plant Potamogeton alpinus in running waters

    PubMed Central

    Robionek, Alicja; Banaś, Krzysztof; Chmara, Rafał; Szmeja, Józef

    2015-01-01

    Aquatic plants anchored in streams are under pressure from various constraints linked to the water flow and display strategies to prevent their damage or destruction. We assume that the responses of aquatic plants to fast-water flow are a manifestation of a trade-off consisting in either maximizing the resistance to damage (tolerance strategy) in minimizing the hydrodynamic forces (avoidance strategy), or both. Our main hypothesis was that Potamogeton alpinus demonstrate the avoidance strategy. We analyzed architecture traits of the modules of this clonal plant from slow- and fast-flowing streams. In fast-flowing waters, the avoidance strategy of P. alpinus is reflected by the following: (1) the presence of floating leaves that stabilize the vertical position of the stem and protect the inflorescence against immersion; (2) elongation of submerged leaves (weakens the pressure of water); and (3) shoot diameter reduction and increase in shoot density (weakens the pressure of water, increases shoot elasticity), and by contrast in slow-water flow include the following: (4) the absence of floating leaves in high intensity of light (avoiding unnecessary outlays on a redundant organ); (5) the presence of floating leaves in low intensity of light (avoidance of stress caused by an insufficient assimilation area of submerged leaves). PMID:26380667

  4. Toxic effects of nickel oxide bulk and nanoparticles on the aquatic plant Lemna gibba L.

    PubMed

    Oukarroum, Abdallah; Barhoumi, Lotfi; Samadani, Mahshid; Dewez, David

    2015-01-01

    The aquatic plant Lemna gibba L. was used to investigate and compare the toxicity induced by 30 nm nickel oxide nanoparticles (NiO-NPs) and nickel(II) oxide as bulk (NiO-Bulk). Plants were exposed during 24 h to 0-1000 mg/L of NiO-NPs or NiO-Bulk. Analysis of physicochemical characteristics of nanoparticles in solution indicated agglomerations of NiO-NPs in culture medium and a wide size distribution was observed. Both NiO-NPs and NiO-Bulk caused a strong increase in reactive oxygen species (ROS) formation, especially at high concentration (1000 mg/L). These results showed a strong evidence of a cellular oxidative stress induction caused by the exposure to NiO. Under this condition, NiO-NPs and NiO-Bulk induced a strong inhibitory effect on the PSII quantum yield, indicating an alteration of the photosynthetic electron transport performance. Under the experimental conditions used, it is clear that the observed toxicity impact was mainly due to NiO particles effect. Therefore, results of this study permitted determining the use of ROS production as an early biomarker of NiO exposure on the aquatic plant model L. gibba used in toxicity testing.

  5. Toxic Effects of Nickel Oxide Bulk and Nanoparticles on the Aquatic Plant Lemna gibba L.

    PubMed Central

    Oukarroum, Abdallah; Barhoumi, Lotfi; Samadani, Mahshid

    2015-01-01

    The aquatic plant Lemna gibba L. was used to investigate and compare the toxicity induced by 30 nm nickel oxide nanoparticles (NiO-NPs) and nickel(II) oxide as bulk (NiO-Bulk). Plants were exposed during 24 h to 0–1000 mg/L of NiO-NPs or NiO-Bulk. Analysis of physicochemical characteristics of nanoparticles in solution indicated agglomerations of NiO-NPs in culture medium and a wide size distribution was observed. Both NiO-NPs and NiO-Bulk caused a strong increase in reactive oxygen species (ROS) formation, especially at high concentration (1000 mg/L). These results showed a strong evidence of a cellular oxidative stress induction caused by the exposure to NiO. Under this condition, NiO-NPs and NiO-Bulk induced a strong inhibitory effect on the PSII quantum yield, indicating an alteration of the photosynthetic electron transport performance. Under the experimental conditions used, it is clear that the observed toxicity impact was mainly due to NiO particles effect. Therefore, results of this study permitted determining the use of ROS production as an early biomarker of NiO exposure on the aquatic plant model L. gibba used in toxicity testing. PMID:26075242

  6. Ecological life histories of the three aquatic nuisance plants, Myriophyllum spicatum, Potamogeton crispus and Elodea canadensis

    USGS Publications Warehouse

    Nichols, S.A.; Shaw, B.H.

    1986-01-01

    The life histories of Myriophyllum spicatum L., Elodea canadensis Michx., and Potamogeton crispus L., serious aquatic nuisances in many regions of the world, are reviewed to provide insights into the life style of successful aquatic nuisance plants. Specifically, their distribution and spread in North America; their life cycle, productive and reproductive potential; and their ecosystem relationships are reviewed. Hopefully this review will improve a manager's ability to deal with aquatic nuisance problems. It also provides suggestions for basic research needed to develop more effective management practices. It was found that all three species possess a number of adaptations, including an ability to rapidly propagate vegetatively, an opportunistic nature for obtaining nutrients, a life cycle that favors cool weather, and a number of mechanisms which enhance photosynthetic efficiency, which allow them to proliferate. These three species do provide benefits to the ecosystem through their roles in materials cycling and energy flow. Therefore, management of these species should take an integrated approach which recognizes these benefits. The life history information available about the three species varies tremendously; however, a better understanding of resource gain and allocation is needed to manage all three species. Specifically, more research is needed to provide a better understanding of: 1) the role bicarbonate plays in photosynthesis, 2) the role roots play in supplying CO2 to the plabts, 3) resource accumulation and allocation under different temperature and light regimes, 4) resource allocation on a seasonal basis, and 5) nutrient cycling under different management regimes. ?? 1986 Dr W. Junk Publishers.

  7. Density-dependent reproductive and vegetative allocation in the aquatic plant Pistia stratiotes (Araceae).

    PubMed

    Coelho, Flávia Freitas; Deboni, Liene; Lopes, Frederico Santos

    2005-01-01

    Pistia stratiotes is an aquatic macrophyte that grows in temporary-ponds in the southern Pantanal, Brazil. It reproduces both sexually and asexually and is usually observed forming dense mats on the water surface, a condition favored by the plant's vegetative reproduction coupled with an ability for rapid growth. In this study we examined the effect of densely crowded conditions on the production of reproductive and vegetative structures. In addition, we verified whether there is a trade-off between clonal growth and investment in sexual reproductive structures, and whether there is an allocation pattern with plant size. Individual plant biomass and the number of the rosettes producing sexual reproductive structures and vegetative growth structures both increased with density. Increase in plant size resulted in increased proportional allocation to sexual reproductive structures and vegetative growth structures. Allocation of biomass to reproduction did not occur at the expense of clonal growth. Thus, the density response appears as a increase of rosettes producing sexual reproductive structures and vegetative growth structures. Therefore, long leaves and stolons may be adaptive under densely crowded conditions where competition for light is intense. An important aspect in the study of trade-offs is the size-dependency of the allocation patterns .Usually, larger plants produce more biomass. Therefore, larger plants can allocate more biomass to both vegetative and sexual reproduction than smaller plants and thus show a positive correlation between both traits rather than the expected negative one.

  8. Development of microsatellite markers for Euryale ferox (Nymphaeaceae), an endangered aquatic plant species in Japan.

    PubMed

    Imanishi, Ayumi; Kaneko, Shingo; Isagi, Yuji; Imanishi, Junichi; Natuhara, Yosihiro; Morimoto, Yukihiro

    2011-08-01

    Microsatellite markers were developed to investigate genetic diversity and genetic structure of Euryale ferox, a vulnerable aquatic plant. Ten microsatellite loci were isolated and characterized for this species. Eight loci showed polymorphisms with two or three alleles per locus. As for the polymorphic markers, the expected and observed heterozygosities ranged from 0.00 to 0.08 and 0.17 to 0.64, respectively. The 10 microsatellite markers described here will be useful for investigating genetic diversity, genetic structure, and gene flow between populations of E. ferox.

  9. Introduction of human pharmaceuticals from wastewater treatment plants into the aquatic environment: a rural perspective.

    PubMed

    Nebot, Carolina; Falcon, Raquel; Boyd, Kenneth G; Gibb, Stuart W

    2015-07-01

    Incomplete removal of pharmaceuticals during wastewater treatment can result in their discharge into the aquatic environment. The discharge of pharmaceuticals in wastewater treatment plant (WWTP) effluents into rivers, lakes and the oceans has led to detectable concentrations of pharmaceuticals in the aquatic environment in many countries. However, to date studies of WWTP discharges into the aquatic environment have largely been confined to areas of relatively high population density, industrial activity or systems impacted on by such areas. In this work, two sites in the far north of Scotland were used to assess whether, and which, pharmaceuticals were being introduced into natural waters in a rural environment with low population density. Samples from two WWTPs (with differing modes of operation), and one receiving water, the River Thurso, were analysed for the presence of 12 pharmaceuticals (diclofenac, clofibric acid, erythromycin, ibuprofen, mefenamic acid, paracetamol, propranolol, sulfamethoxazole, tamoxifen, trimethoprim and dextropropoxyphene). Ten of the 12 pharmaceuticals investigated were detected in at least one of the 40 WWTP effluent samples. Maximum concentrations ranged from 7 ng L(-1) (sulfamethoxazole) to 22.8 μg L(-1) (paracetamol) with diclofenac and mefenamic acid being present in all of samples analysed at concentrations between 24.2 and 927 ng L(-1) and 11.5 and 22.8 μg L(-1), respectively. Additionally, the presence of four pharmaceuticals at ng L(-1) levels in the River Thurso, into which one of the WWTPs discharges, shows that such discharges result in measurable levels of pharmaceuticals in the environment. This provides direct evidence that, even in rural areas with low population densities, effluents from WWTPs can produce quantifiable levels of human pharmaceutical in the natural aquatic environment. These observations indicate that human pharmaceuticals may be considered as contaminants, with potential to influence water quality

  10. Silver nanoparticle toxicity effect on growth and cellular viability of the aquatic plant Lemna gibba.

    PubMed

    Oukarroum, Abdallah; Barhoumi, Lotfi; Pirastru, Laura; Dewez, David

    2013-04-01

    The toxicity effect of silver nanoparticles (AgNPs) on growth and cellular viability was investigated on the aquatic plant Lemna gibba exposed over 7 d to 0, 0.01, 0.1, 1, and 10 mg/L of AgNPs. Growth inhibition was demonstrated by a significant decrease of frond numbers dependent on AgNP concentration. Under these conditions, reduction in plant cellular viability was detected for 0.1, 1, and 10 mg/L of AgNPs within 7 d of AgNPs treatment. This effect was highly correlated with the production of intracellular reactive oxygen species (ROS). A significant increase of intracellular ROS formation was triggered by 1 and 10 mg/L of AgNP exposure. The induced oxidative stress was related to Ag accumulation within L. gibba plant cells and with the increasing concentration of AgNP exposure in the medium. The authors' results clearly suggested that AgNP suspension represented a potential source of toxicity for L. gibba plant cells. Due to the low release capacity of free soluble Ag from AgNP dissolution in the medium, it is most likely that the intracellular uptake of Ag was directly from AgNPs, triggering cellular oxidative stress that may be due to the release of free Ag inside plant cells. Therefore, the present study demonstrated that AgNP accumulation in an aquatic environment may represent a potential source of toxicity and a risk for the viability of duckweeds. Copyright © 2013 SETAC.

  11. Molecular Adaptation of rbcL in the Heterophyllous Aquatic Plant Potamogeton

    PubMed Central

    Iida, Satoko; Miyagi, Atsuko; Aoki, Seishiro; Ito, Motomi; Kadono, Yasuro; Kosuge, Keiko

    2009-01-01

    Background Heterophyllous aquatic plants show marked phenotypic plasticity. They adapt to environmental changes by producing different leaf types: submerged, floating and terrestrial leaves. By contrast, homophyllous plants produce only submerged leaves and grow entirely underwater. Heterophylly and submerged homophylly evolved under selective pressure modifying the species-specific optima for photosynthesis, but little is known about the evolutionary outcome of habit. Recent evolutionary analyses suggested that rbcL, a chloroplast gene that encodes a catalytic subunit of RuBisCO, evolves under positive selection in most land plant lineages. To examine the adaptive evolutionary process linked to heterophylly or homophylly, we analyzed positive selection in the rbcL sequences of ecologically diverse aquatic plants, Japanese Potamogeton. Principal Findings Phylogenetic and maximum likelihood analyses of codon substitution models indicated that Potamogeton rbcL has evolved under positive Darwinian selection. The positive selection has operated specifically in heterophyllous lineages but not in homophyllous ones in the branch-site models. This suggests that the selective pressure on this chloroplast gene was higher for heterophyllous lineages than for homophyllous lineages. The replacement of 12 amino acids occurred at structurally important sites in the quaternary structure of RbcL, two of which (residue 225 and 281) were identified as potentially under positive selection. Conclusions/Significance Our analysis did not show an exact relationship between the amino acid replacements and heterophylly or homophylly but revealed that lineage-specific positive selection acted on the Potamogeton rbcL. The contrasting ecological conditions between heterophyllous and homophyllous plants have imposed different selective pressures on the photosynthetic system. The increased amino acid replacement in RbcL may reflect the continuous fine-tuning of RuBisCO under varying ecological

  12. Evolutionary divergence and possible incipient speciation in post-glacial populations of a cosmopolitan aquatic plant.

    PubMed

    Nies, G; Reusch, T B H

    2005-01-01

    Habitat configuration is expected to have a major influence on genetic exchange and evolutionary divergence among populations. Aquatic organisms occur in two fundamentally different habitat types, the sea and freshwater lakes, making them excellent models to study the contrasting effects of continuity vs. isolation on genetic divergence. We compared the divergence in post-glacial populations of a cosmopolitan aquatic plant, the pondweed Potamogeton pectinatus that simultaneously occurs in freshwater lakes and coastal marine sites. Relative levels of gene flow were inferred in 12 lake and 14 Baltic Sea populations in northern Germany using nine highly polymorphic microsatellite markers developed for P. pectinatus. We found highly significant isolation-by-distance in both habitat types (P < 0.001). Genetic differentiation increased approximately 2.5-times faster among freshwater populations compared with those from the Baltic Sea. As different levels of genetic drift or population history cannot explain these differences, higher population connectivity in the sea relative to freshwater populations is the most likely source of contrasting evolutionary divergence. These findings are consistent with the notion that freshwater angiosperms are more conducive to allopatric speciation than their life-history counterparts in the sea, the relative species poor seagrasses. Surprisingly, population pairs from different habitat types revealed almost maximal genetic divergence expected for complete reproductive isolation, regardless of their respective geographical distance. Hence, the barrier to gene flow between lake and sea habitat types cannot be due to dispersal limitation. We may thus have identified a case of rapid incipient speciation in post-glacial populations of a widespread aquatic plant.

  13. Microbial plant litter decomposition in aquatic and terrestrial boreal systems along a natural fertility gradient

    NASA Astrophysics Data System (ADS)

    Soares, A. Margarida P. M.; Kritzberg, Emma S.; Rousk, Johannes

    2017-04-01

    Plant litter decomposition is a global ecosystem process, with a crucial role in carbon and nutrient cycling. The majority of litter processing occurs in terrestrial systems, but an important fraction also takes place in inland waters. Among environmental factors, pH impacts the litter decomposition through its selective influence on microbial decomposers. Fungal communities are less affected by pH than bacteria, possibly owing to a wider pH tolerance by this group. On the other hand, bacterial pH optima are constrained to a narrower range of pH values. The microbial decomposition of litter is universally nutrient limited; but few comparisons exist between terrestrial and aquatic systems. We investigated the microbial colonisation and decomposition of plant litter along a fertility gradient, which varied in both pH and N availability in both soil and adjacent water. To do this we installed litterbags with birch (Betula pendula) in streams and corresponding soils in adjacent riparian areas in a boreal system, in Krycklan, Sweden. During the four months covering the ice-free growth season we monitored the successional dynamics of fungal (acetate incorporation into ergosterol) and bacterial growth (thymidine incorporation), microbial respiration in leaf litter, and quantitative and qualitative changes in litter over time. We observed that bacterial growth rates were initially higher in litter decomposing in streams than those in soils, but differences between terrestrial and aquatic bacterial production converged towards the end of the experiment. In litter bags installed in soils, bacterial growth was lower at sites with more acidic pH and lower N availability, while aquatic bacteria were relatively unaffected by the fertility level. Fungal growth rates were two-fold higher for litter decomposing in streams than in soils. In aquatic systems, fungal growth was initially lower in low fertility sites, but differences gradually disappeared over the time course. Fungal

  14. Toxic effects of traditional Ethiopian fish poisoning plant Milletia ferruginea (Hochst) seed extract on aquatic macroinvertebrates.

    PubMed

    Karunamoorthi, K; Bishaw, D; Mulat, T

    2009-01-01

    The present investigation was carried out to evaluate the toxic effects of traditional Ethiopian fish poisoning plant Birbira [vernacular name (local native language, Amharic); Milletia ferruginea] seed extract on aquatic macroinvertebrates, Baetidae (Mayflies) and Hydropsychidae (Caddisflies), under laboratory conditions. In Ethiopia, toxic plant; Milletia ferruginea pulverized seeds have been used for fish poisoning since time immemorial. Macroinvertebrates are important biological indicators of alteration in the natural water sources. Milletia ferruginea seed extract was applied at concentrations of 125, 250, 500 1000 and 2000 ppm on Hydropsychididae whereas Baetidae were exposed at various concentrations viz., 31.25, 62.5, 125, 250 & 500 ppm. Milletia ferruginea seeds crude extract of lethal doses (LCso and LC90) required for Baetidae 49.29 mg/l and 172.52 mg/l were respectively and the respective doses (LC50 and LC90) against Hydropsychidae were 679.64 mg/l and 2383.93 mg/l. The present investigation end result demonstrated that Milletia ferruginea seed extracts were extremely toxic to Baetidae than Hydropsychididae. As a result, application of Milletia ferruginea seed extracts into the rivers/streams for fish poisoning possibly leads to contamination and disruption of food chain in the aquatic ecosystem. Therefore, the concerned authorities should launch appropriate awareness campaign among the local inhabitants and fisherman about adverse effect of Birbira seed extracts. Furthermore, providing alternative ecofriendly techniques for fish harvesting may possibly bring constructive out come in the near future.

  15. Hydrologic modeling of aquatic plant treatment systems polishing dairy lagoon effluents.

    PubMed

    Cothren, G M; Chen, S; Rahman, M; Malone, R

    2001-01-01

    In this study, a mathematical model of the hydrologic balance of an aquatic plant treatment system (APTS) has been developed. The mass balance approach has been adopted and the major components of the water balance, such as precipitation, evapotranspiration (ET) and percolation have been incorporated into the model. For estimation of ET for duckweed and water hyacinth plants, mathematical relationships were established between ET and pan evaporation using data collected at the site. The observed ET rates of water hyacinths were up to 66% higher than the pan evaporation rates. But for duckweed, the observed ET rates were 10 to 20% lower than the pan evaporation rates. Using the available historic precipitation and pan evaporation data, several computer simulations of the model were run to estimate the HLR and HRT of the ponds under different design requirements. The results indicate that aquatic ponds with water hyacinths can operate at greater HLR's than ponds supporting duckweed. For a zero discharge system, the allowable HLR for a water hyacinth pond was found to be 5 times that of a pond containing duckweed.

  16. Effects of acidification on metal accumulation by aquatic plants and invertebrates. 1. Constructed wetlands

    SciTech Connect

    Albers, P.H.; Camardese, M.B. . Patuxent Wildlife Research Center)

    1993-06-01

    Compared were concentrations of Al,Cd,Ca,Cu,Fe,Hg,Pb,Mg,Mn,Ni,P, and Zn in water, plants and aquatic insects of three acidified (pH [approximately] 5.0) and three nonacidified (pH [approximately] 6.5) constructed wetlands. Concentrations of Zn in water and bur-reed (Sparganium americanum) were higher in acidified wetlands than in nonacidified wetlands. Floating nonrooted plants contained mean concentrations of Fe, Mg, and Mn that were higher than recommended maximum levels for poultry feed. The mean concentrations of all metals in insects were below recommended maximum levels for poultry feed and below levels that cause toxic effects in wild birds. Smaller than expected increases of metal concentrations in the water of acidified wetlands were probably due to limited mobilization of metals from the sediments and insignificant changes in sedimentation of aqueous metals. Calcium was lower in acidified than in nonacidified wetland water, but the Ca content of insects and bur-reed was not lower. Low concentrations of Ca in aquatic insects from both groups of wetlands indicated that calcium-rich crustaceans and mollusks are probably important to female waterfowl and their young during the spring, when invertebrates make up the majority of the diet. Although toxic effects from metal ingestion seem to be unlikely consequences of wetland acidification, the adverse effect of low pH on the occurrence of crustaceans and mollusks could threatened egg production and development of young.

  17. Genetic uniformity characterizes the invasive spread of water hyacinth (Eichhornia crassipes), a clonal aquatic plant.

    PubMed

    Zhang, Yuan-Ye; Zhang, Da-Yong; Barrett, Spencer C H

    2010-05-01

    Aquatic plant invasions are often associated with long-distance dispersal of vegetative propagules and prolific clonal reproduction. These reproductive features combined with genetic bottlenecks have the potential to severely limit genetic diversity in invasive populations. To investigate this question we conducted a global scale population genetic survey using amplified fragment length polymorphism markers of the world's most successful aquatic plant invader -Eichhornia crassipes (water hyacinth). We sampled 1140 ramets from 54 populations from the native (South America) and introduced range (Asia, Africa, Europe, North America, Central America and the Caribbean). Although we detected 49 clones, introduced populations exhibited very low genetic diversity and little differentiation compared with those from the native range, and approximately 80% of introduced populations were composed of a single clone. A widespread clone ('W') detected in two Peruvian populations accounted for 70.9% of the individuals sampled and dominated in 74.5% of the introduced populations. However, samples from Bangladesh and Indonesia were composed of different genotypes, implicating multiple introductions to the introduced range. Nine of 47 introduced populations contained clonal diversity suggesting that sexual recruitment occurs in some invasive sites where environmental conditions favour seedling establishment. The global patterns of genetic diversity in E. crassipes likely result from severe genetic bottlenecks during colonization and prolific clonal propagation. The prevalence of the 'W' genotype throughout the invasive range may be explained by stochastic sampling, or possibly because of pre-adaptation of the 'W' genotype to tolerate low temperatures.

  18. Adaptations to increasing hydraulic stress: morphology, hydrodynamics and fitness of two higher aquatic plant species.

    PubMed

    Puijalon, Sara; Bornette, Gudrun; Sagnes, Pierre

    2005-02-01

    Sessile organisms often exhibit morphological changes in response to permanent exposure to mechanical stimulation (wind or water movements). The adaptive value of these morphological changes (hydrodynamic performance and consequences on fitness) has not been studied extensively, particularly for higher plants submitted to flow stress. The aim was to determine the adaptive value of morphological patterns observed within two higher aquatic plant species, Berula erecta and Mentha aquatica, growing along a natural flow stress gradient. The hydrodynamic ability of each ramet was investigated through quantitative variables (drag coefficient and E-value). Fitness-related traits based on vegetative growth and clonal multiplication were assessed for each individual. For both species, the drag coefficient and the E-value were explained only to a limited extent by the morphological traits used. B. erecta exhibited a reduction in size and low overall plant drag at higher flow velocities, despite high drag values relative to leaf area, due to a low flexibility. The plants maintained their fitness, at least in part, through biomass reallocation: one tall ramet at low velocity, but shorter individuals with many interconnected stolons when flow velocity increased. For M. aquatica, morphological differences along the velocity gradient did not lead to greater hydrodynamic performance. Plant size increased with increasing velocities, suggesting the indirect effects of current favouring growth in high velocities. The fitness-related traits did not demonstrate lower plant fitness for high velocities. Different developmental constraints linked to plant morphology and trade-offs between major plant functions probably lead to different plant responses to flow stress.

  19. Managing invasive aquatic plants in a changing system: strategic consideration of ecosystem services.

    PubMed

    Hershner, Carl; Havens, Kirk J

    2008-06-01

    Climate change is projected to increase stress for many coastal plant communities. Along large portions of the North American coast, habitat degradation from anthropogenic changes to the environment already threaten the community structure of tidal marshes and submerged aquatic grass beds. The potential loss of ecological services historically provided by these communities has been a long-standing rationale for aggressive control of invading plants such as Phragmites australis and Hydrilla verticillata. Increasing evidence of ecological services provided by invasive species such as P. australis and H. verticillata suggest that, in the face of increasing stress, it may be prudent to take a more pragmatic approach regarding the effect of these species on coastal ecosystems. The notable resilience of these species to control efforts and their competitive success and comparative vigor in stressed systems and capacity to provide at least some beneficial services combine to suggest some invasive species may have a useful role in managed coastal ecosystems.

  20. [Spatial-Temporal variability of aquatic plant communities in the Venezuelan Llanos].

    PubMed

    Rial B, Anabel

    2006-06-01

    The richness and abundance of aquatic plant communities were studied in 14 habitats of the Venezuelan "llanos" (07 degrees 35'-07 degrees 55' N-68 degrees 50'-69 degrees 00' W, Apure) during an annual cycle. Annual means were 27 degrees C, 115 mm rainfall and 77% relative humidity. A permanent transect was set in each habitat (ten consecutive square meter quadrats from the shore to the water). The plants and the area they covered in each quadrat were recorded monthly for a year. The total richness was 69 species. Alatalo and Alatalo's diversity analysis indicates that season, and its correlate, water level, influence species diversity and abundance more than habitat (spatial factor: geometric index-Euclidean distance).

  1. Efficient distinction of invasive aquatic plant species from non-invasive related species using DNA barcoding.

    PubMed

    Ghahramanzadeh, R; Esselink, G; Kodde, L P; Duistermaat, H; van Valkenburg, J L C H; Marashi, S H; Smulders, M J M; van de Wiel, C C M

    2013-01-01

    Biological invasions are regarded as threats to global biodiversity. Among invasive aliens, a number of plant species belonging to the genera Myriophyllum, Ludwigia and Cabomba, and to the Hydrocharitaceae family pose a particular ecological threat to water bodies. Therefore, one would try to prevent them from entering a country. However, many related species are commercially traded, and distinguishing invasive from non-invasive species based on morphology alone is often difficult for plants in a vegetative stage. In this regard, DNA barcoding could become a good alternative. In this study, 242 samples belonging to 26 species from 10 genera of aquatic plants were assessed using the chloroplast loci trnH-psbA, matK and rbcL. Despite testing a large number of primer sets and several PCR protocols, the matK locus could not be amplified or sequenced reliably and therefore was left out of the analysis. Using the other two loci, eight invasive species could be distinguished from their respective related species, a ninth one failed to produce sequences of sufficient quality. Based on the criteria of universal application, high sequence divergence and level of species discrimination, the trnH-psbA noncoding spacer was the best performing barcode in the aquatic plant species studied. Thus, DNA barcoding may be helpful with enforcing a ban on trade of such invasive species, such as is already in place in the Netherlands. This will become even more so once DNA barcoding would be turned into machinery routinely operable by a nonspecialist in botany and molecular genetics.

  2. Phytochelatin synthesis in response to Hg uptake in aquatic plants near a chlor-alkali factory.

    PubMed

    Turull, Marta; Grmanova, Gabriela; Dago, Àngela; Ariño, Cristina; Díez, Sergi; Díaz-Cruz, José Manuel; Esteban, Miquel

    2017-06-01

    The effects of mercury (Hg) released from a chlor-alkali factory in aquatic plants along the Ebro River basin (NE Spain) were analysed considering the phytochelatins (PCn) and their isoforms content in these plants. These compounds were analyzed using HPLC with amperometric detection, and the macrophytes species Ceratophyllum demersum and Myriopyllum spicatum were collected in two sampling campaigns, autumn and spring, respectively. To correlate the PCn content in macrophytes with the Hg contamination, analysis of total Hg (THg) content in plants and suspended particulate matter, as well as the dissolved-bioavailable fraction of Hg in water measured by the diffusive gradient in thin film (DGT) technique were done. The results confirm the presence of PC2-Ala in extracts of C. demersum and PC2-desGly in M. spicatum, and the concentration of these thiol compounds depends clearly on the distance between the hot spot and the downstream sites: the higher the levels are, the closer the hot spot is. Since most of the Hg is hypothesized to be associated with SPM and transported downstream, our results of the DGT suggest that trace amounts of Hg in water can be released as free metal ions yielding a certain accumulation in plants (reaching the ppb level) that are enough for activation of induction of PCs. A few PCs species have been determined, at different seasons, indicating that they can be used as good indicators of the presence of bioavailable Hg in aquatic media throughout the year. Copyright © 2017 Elsevier Ltd. All rights reserved.

  3. Potential for chromium (VI) bioremediation by the aquatic carnivorous plant Utricularia gibba L. (Lentibulariaceae).

    PubMed

    Augustynowicz, Joanna; Łukowicz, Krzysztof; Tokarz, Krzysztof; Płachno, Bartosz Jan

    2015-07-01

    The aquatic carnivorous plant Utricularia gibba has one of the smallest known genomes among flowering plants, and therefore, it is an excellent model organism for physiological and developmental studies. The main aim of our work was to check whether the ubiquitous U. gibba might be useful for the phytoremediation of the highly toxic and mobile hexavalent chromium in waters. Plants were incubated for 1 week in a 50 μM (2.6 mg dm(-3)) Cr(VI) solution in laboratory conditions. Our results revealed that the plant exhibits a very high accumulation capacity for Cr. The accumulation level was higher than 780 mg kg(-1) and a bioconcentration factor >300. On the other hand, the plants showed a low tolerance to the elevated Cr concentration, which was expressed in a significant decrease of the photosystem II activity. However, the most pronounced negative influence of chromate was found on the morphology and activity of the traps. Due to its high accumulation capacity, we suggest that U. gibba may be efficient in the removal of chromate over a short time scale. It can also provide a new molecular resource for studying the mechanisms of Cr(VI) detoxification.

  4. Proceedings, Annual Meeting, Aquatic Plant Control Research Program (17th) Held at Sacramento, California on 16-18 November 1982.

    DTIC Science & Technology

    1983-06-01

    Miscellaneous Paper A-77-3. PROGRAM PROJECTIONS - Due to the biological nature of the aquatic plant problem and the exponential growth rate of the main nuisance...endemic fungal plant pathogen. (2) Arzama densa (pickerelweed moth), native to the United States. IMPLEMENTING BIOCONTROL METHODS Collection of...describe the effects on the remaining plant community. This work was con-dAued by the Floridg)epartment of Natural Resources, Tallahassee. fi’Hydrology and

  5. Methods for assessing the toxicity of herbicides to submersed aquatic plants.

    PubMed

    Knauer, Katja; Vervliet-Scheebaum, Marco; Dark, Roberta J; Maund, Stephen J

    2006-08-01

    A new test design for the non-axenic submergent aquatic macrophytes Elodea canadensis Michx. and Myriophyllum spicatum L. has been developed for potential use in herbicide toxicity testing. For the non-axenic cultures, the best growth conditions were observed in the Elendt-M4 medium in which no growth of algae or bacteria was observed. Cuttings were placed in beakers containing only the artificial M4 medium or were planted in small beakers containing OECD (Organisation for Economic Cooperation and Development) sediment (5% peat, 75% sand, 20% kaolinite), which were then placed in larger vessels with the M4 medium. The plants were observed for main and secondary shoot length, biomass and root formation within 2-3 weeks of planting. Growth rates were calculated for total plant length and biomass. The variance between the replicates was low throughout the experiment [coefficient of variation (CV) < 26% for total plant length, and between 16 and 40% for biomass]. Relative growth rates based on total plant length were determined as 0.028 and 0.050 per day for M. spicatum in the systems containing M4 medium only and medium plus sediment respectively. Similar results were observed for E. canadensis, with relative growth rates of 0.26 and 0.073 per day in the two test systems. The root-shoot ratio at harvest was greater by a factor of 2-3 for E. canadensis in the M4 medium than in the system containing sediment. However, comparable ratios were observed for M. spicatum in the two test systems. Both growth in total plant length and growth in biomass of the two species have potential as measures of toxicity.

  6. Colonization of a Submersed Aquatic Plant, Eurasian Water Milfoil (Myriophyllum spicatum), by Fungi under Controlled Conditions

    PubMed Central

    Smith, Craig S.; Chand, Tara; Harris, Robin F.; Andrews, John H.

    1989-01-01

    A laboratory assay to assess colonization of a submersed aquatic plant, Eurasian water milfoil (Myriophyllum spicatum), by fungi was developed and used to evaluate the colonization potential of Colletotrichum gloeosporioides, Acremonium curvulum, Cladosporium herbarum, Aureobasidium pullulans, a Paecilomyces sp., and an unidentified sterile, septate fungus. Stem segments of plants were first immersed in suspensions of fungal propagules for 24 h and then washed to remove all but the tightly attached component of the population. Inoculation was followed by two growth cycles of 3 days each. At the start of each cycle, washed plants were transferred to a mineral salts medium to provide an opportunity for the attached fungal populations to grow. After each growth period, plants were again washed, and fungal populations in the medium (nonattached), loosely attached and tightly attached to the plant, and within the plant (endophytic) were assayed by dilution plating. The fungi differed in the extent to which they attached to water milfoil and in their ability to grow in association with it. There were relatively few significant differences among the tightly attached fungal populations after 24 h, but growth of the better colonizers led to a greater number of significant differences after 4 and 7 days. In addition, the better colonizers showed sustained regrowth of loosely and nonattached fungal propagules in the face of intermittent removal by washing. A milfoil pathogen, C. gloeosporioides, was the only endophytic colonizer; it was also among the best epiphytic colonizers but was not demonstrably better than A. curvulum, a fungus commonly found as an epiphyte on watermilfoil. The yeastlike hyphomycete Aureobasidium pullulans was the only fungus that consistently failed to establish an increasing population on the plant. Images PMID:16348013

  7. Fate of methane in aquatic systems dominated by free-floating plants.

    PubMed

    Kosten, Sarian; Piñeiro, Marcia; de Goede, Eefje; de Klein, Jeroen; Lamers, Leon P M; Ettwig, Katharina

    2016-11-01

    Worldwide the area of free-floating plants is increasing, which can be expected to alter methane (CH4) emissions from aquatic systems in several ways. A large proportion of the CH4 produced may become oxidized below the plants due to the accumulation of CH4 as a result of a decrease in the diffusive water-atmosphere flux and the entrapment of part of the ebullitive CH4, in combination with suitable conditions for methane oxidizing (MOX) bacteria in the aerobic rhizosphere. We used a set of essays to test this hypothesis and to explore the effect of different densities for three widespread free-floating species: Azolla filiculoides, Salvinia natans, and Eichhornia crassipes. The gas exchange velocity, proportion of CH4 bubbles trapped by the plants, occurrence of radial oxygen loss from roots, and MOX rates on the roots were assessed. We subsequently used the outcome of these experiments to parameterize a simple model. With this model we estimated the proportion of the produced CH4 that is oxidized, for different plant species and different densities. We found that in a shallow (1 m) system up to 70% of the CH4 produced may become oxidized as a result of a strong decrease in gas exchange combined with high MOX activity of the rhizosphere microbiome. As floating plants also are likely to increase CH4 production by organic matter production, especially when their presence induces anaerobic conditions, the overall effect on CH4 emission will strongly depend on local conditions. This explains the contrasting effects of floating plants on CH4 emissions in literature as reviewed here. As the effect of floating plants on CH4 emissions, including the high MOX rates we show here, can be substantial, there is an urgent need to consider this impact when assessing greenhouse gas budgets. Copyright © 2016 Elsevier Ltd. All rights reserved.

  8. Development and validation of phytotoxicity tests with emergent and submerged aquatic plants

    SciTech Connect

    Hughes, J.S.; Powell, R.L.; Nelson, M.K.

    1995-12-31

    Toxicity testing procedures have recently been developed for assessment of contaminant effects on emergent and submerged aquatic macrophytes commonly found in freshwater wetlands. These tests have potential application in risk assessments for contaminated wetlands as well as for new chemical substances. The objective of this study was to evaluate and modify, if necessary, these methods and to validate them, using two benchmark chemicals, in a contract laboratory setting. Oryza sativa (domestic rice) was used as a surrogate emergent vascular plant, while Ceratophylium demersum (coontail) and Myriophyllum heterophyllum (variable-leaf milfoil) were the representative submerged vascular plants. Subsequent to evaluating culturing techniques and testing conditions, toxicity tests were conducted using boron and metribuzin. The test procedure for the emergent plants involves a two-week pro-exposure period followed by a two-week aqueous exposure. Five types of sediment, including both natural and artificial sediments, were evaluated for use with rice. Fresh weight and chlorophyll a content were the selected test endpoints. The submerged plants were exposed for two weeks, and the response variables evaluated included length, weight (fresh and dry), and root number. The sensitivity of these tests were comparable to the results obtained for the same two chemicals using the green alga, Selenastrum capricornutum, and the duckweed, Lemna gibba, with the exception that rice was less sensitive to metribuzin than the other species.

  9. Cold climate phosphorus uptake by submerged aquatic plants in a sewage treatment free water surface wetland.

    PubMed

    Ulén, Barbro; Tonderski, Karin S

    2005-01-01

    In November 2002, biomass phosphorus (P) of submerged aquatic plants with associated epiphyton was measured using P-32 tracer addition in a treatment wetland receiving tertiary treated municipal sewage. The wetland is situated 120 km west of Stockholm, Sweden receiving tertiary treated municipal sewage. During the experiment, inflow water had a total P concentration of 0.3 and an iron concentration of 0.7 mg 1(-1) with a residence time of 3-3.5 days. Samples of submerged plants mainly slender waterweed (Elodea nuttallii, L.) and sago pondweed (Potamogeton pectinatus, L.) were taken in two shallow areas (0.21 and 0.51 ha respectively) adjacent to the inlet of one of the wetland subbasins. The sampled area represented 27% of the total 2.6 ha area of the basin. The young phytomass contained 0.02 kg P and the older vegetation parts and epiphyton 0.04 kg P. The sampling took place 90-96 hours after exposure of a pulse of P-32 (18 GBq), i.e. when 75% had passed. Total phytomass was low, only 2 g m(-2) as dry weight. The young phytomass close to the site of injection had higher average beta activity in disintegrations per minute and milligram dry weight (140 DPM mg dw(-1)) than the older parts of the submerged plants (70 DPM mg dw(-1)) indicating an active plant uptake in the former. The latter was interpreted as epiphyton uptake, but since the biomass of old shoots was higher than of young, more P-32 was removed by processes associated with epiphyton as was removed by the young phytomass. In two shallow central zones, the former was equal to 0.006 per thousand of exposed radioactivity in water, while 0.003 per thousand was found in the young phytomass in the same zones of the basin. Close to the inlet a fast P assimilation by the plant biomass was demonstrated. The role of submerged aquatic plants in phosphorus turnover in sewage treatment basins under winter conditions is discussed.

  10. Internal nitrogen removal from sediments by the hybrid system of microbial fuel cells and submerged aquatic plants.

    PubMed

    Xu, Peng; Xiao, En-Rong; Xu, Dan; Zhou, Yin; He, Feng; Liu, Bi-Yun; Zeng, Lei; Wu, Zhen-Bin

    2017-01-01

    Sediment internal nitrogen release is a significant pollution source in the overlying water of aquatic ecosystems. This study aims to remove internal nitrogen in sediment-water microcosms by coupling sediment microbial fuel cells (SMFCs) with submerged aquatic plants. Twelve tanks including four treatments in triplicates were designed: open-circuit (SMFC-o), closed-circuit (SMFC-c), aquatic plants with open-circuit (P-SMFC-o) and aquatic plants with closed-circuit (P-SMFC-c). The changes in the bio-electrochemical characteristics of the nitrogen levels in overlying water, pore water, sediments, and aquatic plants were documented to explain the migration and transformation pathways of internal nitrogen. The results showed that both electrogenesis and aquatic plants could facilitate the mineralization of organic nitrogen in sediments. In SMFC, electrogenesis promoted the release of ammonium from the pore water, followed by the accumulation of ammonium and nitrate in the overlying water. The increased redox potential of sediments due to electrogenesis also contributed to higher levels of nitrate in overlying water when nitrification in pore water was facilitated and denitrification at the sediment-water interface was inhibited. When the aquatic plants were introduced into the closed-circuit SMFC, the internal ammonium assimilation by aquatic plants was advanced by electrogenesis; nitrification in pore water and denitrification in sediments were also promoted. These processes might result in the maximum decrease of internal nitrogen with low nitrogen levels in the overlying water despite the lower power production. The P-SMFC-c reduced 8.1%, 16.2%, 24.7%, and 25.3% of internal total nitrogen compared to SMFC-o on the 55th, 82th, 136th, and 190th days, respectively. The smaller number of Nitrospira and the larger number of Bacillus and Pseudomonas on the anodes via high throughput sequencing may account for strong mineralization and denitrification in the sediments

  11. Internal nitrogen removal from sediments by the hybrid system of microbial fuel cells and submerged aquatic plants

    PubMed Central

    Xu, Peng; Xiao, En-Rong; Xu, Dan; Zhou, Yin; He, Feng; Liu, Bi-Yun; Zeng, Lei; Wu, Zhen-Bin

    2017-01-01

    Sediment internal nitrogen release is a significant pollution source in the overlying water of aquatic ecosystems. This study aims to remove internal nitrogen in sediment-water microcosms by coupling sediment microbial fuel cells (SMFCs) with submerged aquatic plants. Twelve tanks including four treatments in triplicates were designed: open-circuit (SMFC-o), closed-circuit (SMFC-c), aquatic plants with open-circuit (P-SMFC-o) and aquatic plants with closed-circuit (P-SMFC-c). The changes in the bio-electrochemical characteristics of the nitrogen levels in overlying water, pore water, sediments, and aquatic plants were documented to explain the migration and transformation pathways of internal nitrogen. The results showed that both electrogenesis and aquatic plants could facilitate the mineralization of organic nitrogen in sediments. In SMFC, electrogenesis promoted the release of ammonium from the pore water, followed by the accumulation of ammonium and nitrate in the overlying water. The increased redox potential of sediments due to electrogenesis also contributed to higher levels of nitrate in overlying water when nitrification in pore water was facilitated and denitrification at the sediment-water interface was inhibited. When the aquatic plants were introduced into the closed-circuit SMFC, the internal ammonium assimilation by aquatic plants was advanced by electrogenesis; nitrification in pore water and denitrification in sediments were also promoted. These processes might result in the maximum decrease of internal nitrogen with low nitrogen levels in the overlying water despite the lower power production. The P-SMFC-c reduced 8.1%, 16.2%, 24.7%, and 25.3% of internal total nitrogen compared to SMFC-o on the 55th, 82th, 136th, and 190th days, respectively. The smaller number of Nitrospira and the larger number of Bacillus and Pseudomonas on the anodes via high throughput sequencing may account for strong mineralization and denitrification in the sediments

  12. Silver nanoparticles induced reactive oxygen species via photosynthetic energy transport imbalance in an aquatic plant.

    PubMed

    Jiang, Hong Sheng; Yin, Li Yan; Ren, Na Na; Zhao, Su Ting; Li, Zhi; Zhi, Yongwei; Shao, Hui; Li, Wei; Gontero, Brigitte

    2017-03-01

    The rapid growth in silver nanoparticles (AgNPs) commercialization has increased environmental exposure, including aquatic ecosystem. It has been reported that the AgNPs have damaging effects on photosynthesis and induce oxidative stress, but the toxic mechanism of AgNPs is still a matter of debate. In the present study, on the model aquatic higher plant Spirodela polyrhiza, we found that AgNPs affect photosynthesis and significantly inhibit Photosystem II (PSII) maximum quantum yield (Fv/Fm) and effective quantum yield (ΦPSII). The changes of non-photochemical fluorescence quenching (NPQ), light-induced non-photochemical fluorescence quenching [Y(NPQ)] and non-light-induced non-photochemical fluorescence quenching [Y(NO)] showed that AgNPs inhibit the photo-protective capacity of PSII. AgNPs induce reactive oxygen species (ROS) that are mainly produced in the chloroplast. The activity of ribulose-1, 5-bisphosphate carboxylase-oxygenase (Rubisco) was also very sensitive to AgNPs. The internalized Ag, regardless of whether the exposure was Ag(+ )or AgNPs had the same capacity to generate ROS. Our results support the hypothesis that intra-cellular AgNP dissociate into high toxic Ag(+). Rubisco inhibition leads to slowing down of CO2 assimilation. Consequently, the solar energy consumption decreases and then the excess excitation energy promotes ROS generation in chloroplast.

  13. Growth rate effects, responses of antioxidant enzymes and metabolic fate of the herbicide Propanil in the aquatic plant Lemna minor.

    PubMed

    Mitsou, Kiriakoula; Koulianou, Artemissia; Lambropoulou, Dimitra; Pappas, Periklis; Albanis, Triantafyllos; Lekka, Marilena

    2006-01-01

    Propanil (3,4-dichloropropionanilide) is a selective contact pesticide, recommended for post-emergence use in rice. This herbicide may end up in surface waters and present potential risk for aquatic vascular plants. Therefore, its toxicity was evaluated on Lemna minor L., an aquatic plant regularly used for toxicological studies, during time- and concentration-dependent exposure. Toxicity assessments were based on inhibition of growth of L. minor cultures after 24 days. The obtained results showed that the growth of Lemna was affected by the herbicide. The responses of the guaiacol peroxidase (G-POD) and glutathione S-transferase (GST) involved in the xenobiotic metabolism and antioxidative system were also investigated following Propanil exposure. Our results showed that Propanil has not induced enzymatic antioxidative defenses of L. minor. Both 3,4-dichloroaniline (3,4-DCA) and 3,4-dichloroacetanilide are the major metabolites in this plant. On the contrary, only 3,4-DCA was found in culture media after 4 days. Probably, the enzymatic hydrolysis by acyl acylamidase and the acetylation by acetyl-CoA are the major pathways for these transformation products, respectively. The results of this study showed that the selected aquatic plant has the potential to accumulate and metabolize rice herbicide, like Propanil. Based on these toxicity data this herbicide should impair the establishment of non-target aquatic plants.

  14. Interactions of metal-based engineered nanoparticles with aquatic higher plants: A review of the state of current knowledge.

    PubMed

    Thwala, Melusi; Klaine, Stephen J; Musee, Ndeke

    2016-07-01

    The rising potential for the release of engineered nanoparticles (ENPs) into aquatic environments requires evaluation of risks to protect ecological health. The present review examines knowledge pertaining to the interactions of metal-based ENPs with aquatic higher plants, identifies information gaps, and raises considerations for future research to advance knowledge on the subject. The discussion focuses on ENPs' bioaccessibility; uptake, adsorption, translocation, and bioaccumulation; and toxicity effects on aquatic higher plants. An information deficit surrounds the uptake of ENPs and associated dynamics, because the influence of ENP characteristics and water quality conditions has not been well documented. Dissolution appears to be a key mechanism driving bioaccumulation of ENPs, whereas nanoparticulates often adsorb to plant surfaces with minimal internalization. However, few reports document the internalization of ENPs by plants; thus, the role of nanoparticulates' internalization in bioaccumulation and toxicity remains unclear, requiring further investigation. The toxicities of metal-based ENPs mainly have been associated with dissolution as a predominant mechanism, although nano toxicity has also been reported. To advance knowledge in this domain, future investigations need to integrate the influence of ENP characteristics and water physicochemical parameters, as their interplay determines ENP bioaccessibility and influences their risk to health of aquatic higher plants. Furthermore, harmonization of test protocols is recommended for fast tracking the generation of comparable data. Environ Toxicol Chem 2016;35:1677-1694. © 2016 SETAC.

  15. Comparative Studies on Effects of Acid Solutions on Aquatic Plants by Beam Deflection and Absorbance Spectroscopy Methods.

    PubMed

    Wu, Xing-Zheng; Nie, Liangjiao; Inoue, Tomomi

    2015-01-01

    The beam deflection method and absorbance spectroscopy were applied to study effects of acid solutions on aquatic plants, and their results were compared. Aquatic plants Egeria densa and Ceratophyllum demersum L were used as model plants. In absorbance experiments, a piece of the plants was put in a beaker with 20 mL HCl solution, and absorbance of the HCl solution was measured every 30 min. In beam deflection experiments, a probe beam from a He-Ne laser was focused to a vicinity of the plants in a culture dish with HCl solution by an objective lens, and deflection signals of the probe beam were monitored by a position sensor. Absorbance spectra of the HCl solutions with immersing of the plants showed absorbance below 410 nm, suggesting that some compounds leaked from the plants into the HCl solutions. Changes of absorbance and deflection signals with immersion time were examined for different pH levels. The changing trends of the absorbance and deflection signals with time were similar, but the absorbance changes were delayed for about 2 - 3 h. The absorbance method could not detect the effect of the pH 5.0 HCl solutions on the aquatic plants, while the deflection method could.

  16. Compensatory growth in an aquatic plant mediates exploitative competition between seasonally tied herbivores.

    PubMed

    Hidding, Bert; Nolet, Bart A; De Boer, Thujs; De Vries, Peter P; Klaassen, Marcel

    2009-07-01

    The degree to which vertebrate herbivores exploitatively compete for the same food plant may depend on the level of compensatory plant growth. Such compensation is higher when there is reduced density-dependent competition in plants after herbivore damage. Whether there is relief from competition may largely be determined by the life-history stage of plants under herbivory. Such stage-specific compensation may apply to seasonal herbivory on the clonal aquatic plant sago pondweed (Potamogeton pectinatus L.). It winters in sediments of shallow lakes as tubers that are foraged upon by Bewick's Swans (Cygnus columbianus bewickii Yarrell), whereas aboveground biomass in summer is mostly consumed by ducks, coots, and Mute Swans. Here, tuber predation may be compensated due to diminished negative density dependence in the next growth season. However, we expected lower compensation to summer herbivory by waterfowl and fish as density of aboveground biomass in summer is closely related to photosynthetic carbon fixation. In a factorial exclosure study we simultaneously investigated (1) the effect of summer herbivory on aboveground biomass and autumn tuber biomass and (2) the effect of tuber predation in autumn on aboveground biomass and tuber biomass a year later. Summer herbivory strongly influenced belowground tuber biomass in autumn, limiting food availability to Bewick's Swans. In contrast, tuber predation in autumn by Bewick's Swans had a limited and variable effect on P. pectinatus biomass in the following growth season. Whereas relief from negative density dependence largely eliminates effects of belowground herbivory by swans, aboveground herbivory in summer limits both above- and belowground plant biomass. Hence, there was an asymmetry in exploitative competition, with herbivores in summer reducing food availability for belowground herbivores in autumn, but not the other way around.

  17. Endozoochorous dispersal of aquatic plants: does seed gut passage affect plant performance?

    PubMed

    Figuerola, Jordi; Santamaría, Luis; Green, Andy J; Luque, Isabel; Alvarez, Raquel; Charalambidou, Iris

    2005-04-01

    The ingestion of seeds by vertebrates can affect the germinability and/or germination rate of seeds. It is, however, unclear if an earlier germination as a result of ingestion affects later plant performance. For sago pondweed, Potamogeton pectinatus, the effects of seed ingestion by ducks on both germinability and germination rate have been previously reported from laboratory experiments. We performed an experiment to determine the effects of seed ingestion by ducks on germination, seedling survival, plant growth and asexual multiplication. Both at the start and end of the winter, seeds were fed to three captive shovelers (Anas clypeata) and planted outdoors in water-filled containers. Plant biomass and its allocation to vegetative parts (shoot and roots), tubers, and seeds were determined in autumn. More duck-ingested seeds than control (uningested) seeds germinated in early winter, but this difference disappeared for seeds planted in late winter, when the treatments were first stratified for 3 mo. None of the variables for measuring seedling survival and plant performance varied between treatments. Under our experimental conditions (no herbivory or competition), ingestion by ducks in early winter resulted in increased performance for seeds surviving gut passage due to enhanced seed germinability, without other costs or benefits for the seedlings.

  18. Microsatellite markers for Nuphar japonica (Nymphaeaceae), an aquatic plant in the agricultural ecosystem of Japan1

    PubMed Central

    Kondo, Toshiaki; Watanabe, Sonoko; Shiga, Takashi; Isagi, Yuji

    2016-01-01

    Premise of the study: Nuphar species (Nymphaeaceae) are representative aquatic plants in irrigation ponds in Japanese agricultural ecosystems. We developed 15 polymorphic microsatellite markers for N. japonica and confirmed their utility for its close relatives N. oguraensis var. akiensis and N. ×saijoensis, which originated from natural hybridization between N. japonica and N. oguraensis. Methods and Results: Genetic variation was characterized in 15 polymorphic loci in three populations of N. japonica. The average number of alleles per locus was 3.47 (range = 2−9; n = 32), and the average expected heterozygosity per locus was 0.84 (range = 0.5–1.0); 11 loci were amplified in N. oguraensis var. akiensis and 15 in N. ×saijoensis. Conclusions: The polymorphic microsatellite markers developed in this study will be useful for investigating the levels of genetic diversity within remnant populations of Nuphar taxa and could provide a valuable tool for conservation genetics of these taxa. PMID:28101435

  19. Microsatellite markers for Nuphar japonica (Nymphaeaceae), an aquatic plant in the agricultural ecosystem of Japan.

    PubMed

    Kondo, Toshiaki; Watanabe, Sonoko; Shiga, Takashi; Isagi, Yuji

    2016-12-01

    Nuphar species (Nymphaeaceae) are representative aquatic plants in irrigation ponds in Japanese agricultural ecosystems. We developed 15 polymorphic microsatellite markers for N. japonica and confirmed their utility for its close relatives N. oguraensis var. akiensis and N. ×saijoensis, which originated from natural hybridization between N. japonica and N. oguraensis. Genetic variation was characterized in 15 polymorphic loci in three populations of N. japonica. The average number of alleles per locus was 3.47 (range = 2-9; n = 32), and the average expected heterozygosity per locus was 0.84 (range = 0.5-1.0); 11 loci were amplified in N. oguraensis var. akiensis and 15 in N. ×saijoensis. The polymorphic microsatellite markers developed in this study will be useful for investigating the levels of genetic diversity within remnant populations of Nuphar taxa and could provide a valuable tool for conservation genetics of these taxa.

  20. [Study on the reflected and hyperspectral mixed-pixel character of aquatic plants and water].

    PubMed

    Sun, Tian-lin; Zhao, Yun-sheng; Liang, Ren-feng; Zhang, Xia

    2012-02-01

    A study on the reflected and hyperspectral mixed-pixel of aquatic plants and water was given by using a orthogonal experimental design with three factors and two levels. The results of F test suggest that for the single factors, the band and the area ratio of mixed-pixel on the reflected and hyperspectral mixed-pixel of the reflection effects are particularly significant, however, the detector angle had no significant effect under these experimental conditions; For the interaction, the band and the area ratio of mixed-pixel, the detector and the area ratio of mixed-pixel, the effects of these two interactions on the reflected and hyperspectral mixed-pixel are also particularly significant, This study did quantitative analysis of the factors affecting the reflected and hyperspectral mixed-pixel character and their interaction, and provided a new method for the indepth study of mixed-pixel.

  1. Estimation of potential biomass resource and biogas production from aquatic plants in Argentina

    SciTech Connect

    Fitzsimons, R.E.; Laurino, C.N.; Vallejos, R.H.

    1982-08-01

    It is expected that the future construction of the Parana Medio Hydroelectric Project on the middle Parana River in Argentina will lead to the accumulation of floating hydrophytes, mainly water hyacinth. Several problems are related to aquatic plants, and steps for efficient control of the vegetation should be taken. If mechanical control is used, the biomass must be processed, preferably in a useful way. Water hyacinth growth in the middle Parana River has been measured and its bioconversion to methane by anaerobic fermentation determined. It is estimated that gross methane production may be between 1. and 4.1 x 10/sup 9/ m/sup 3//yr. The fermentation residue production, with a potential value as soil condition, may represent between 54.9 and 221.4 x 10/sup 3/t nitrogen/year, i.e., between 2 and 8 times the present nitrogen fertilizer demand in Argentina.

  2. Effects of acidification on metal accumulation by aquatic plants and invertebrates. 1. Constructed wetlands

    USGS Publications Warehouse

    Albers, P.H.; Camardese, M.B.

    1993-01-01

    The pH of lake water is often inversely correlated with concentrations of trace metals in the water column. Concentrations of Al, Cd, Ca, Cu, Fe, Hg, Pb, Mg, Mn, Ni, P, and Zn were compared in water, plants, and aquatic insects from three acidified (pH 5.0) and three nonacidified (pH 6.5) constructed wetlands. Concentrations of Zn in water and bur-reed (Sparganium americanum) were higher in acidified wetlands than in nonacidified wetlands. Floating nonrooted plants contained mean concentrations of Fe, Mg, and Mn that were higher than recommended maximum levels for poultry feed. The mean concentrations of all metals in insects were below recommended maximum levels for poultry feed and below levels that cause toxic effects in wild birds. Smaller than expected increases of metal concentrations in the water of acidified wetlands were probably due to limited mobilization of metals from the sediments and insignificant changes in sedimentation of aqueous metals. Calcium was lower in acidified than in nonacidified wetland water, but the Ca content of insects and bur-reed was not lower. Low concentrations of Ca in aquatic insects from both groups of wetlands indicate that calcium-rich crustaceans and mollusks are probably important to female waterfowl and their young during the spring, when invertebrates make up the majority of the diet. Although toxic effects from metal ingestion seem to be unlikely consequences of wetland acidification, the adverse effect of low pH on the occurrence of crustaceans and mollusks could threaten egg production and development of young.

  3. Plant pigment types, distributions, and influences on shallow water submerged aquatic vegetation mapping

    NASA Astrophysics Data System (ADS)

    Hall, Carlton R.; Bostater, Charles R., Jr.; Virnstein, Robert

    2004-11-01

    Development of robust protocols for use in mapping shallow water habitats using hyperspectral imagery requires knowledge of absorbing and scattering features present in the environment. These include, but are not limited to, water quality parameters, phytoplankton concentrations and species, submerged aquatic vegetation (SAV) species and densities, epiphytic growth on SAV, benthic microalgae and substrate reflectance characteristics. In the Indian River Lagoon, Fl. USA we conceptualize the system as having three possible basic layers, water column and SAV bed above the bottom. Each layer is occupied by plants with their associated light absorbing pigments that occur in varying proportions and concentrations. Phytoplankton communities are composed primarily of diatoms, dinoflagellates, and picoplanktonic cyanobacteria. SAV beds, including flowering plants and green, red, and brown macro-algae exist along density gradients ranging in coverage from 0-100%. SAV beds may be monotypic, or more typically, mixtures of the several species that may or may not be covered in epiphytes. Shallow water benthic substrates are colonized by periphyton communities that include diatoms, dinoflagellates, chlorophytes and cyanobacteria. Inflection spectra created form ASIA hyperspectral data display a combination of features related to water and select plant pigment absorption peaks.

  4. Irritant and Sensitizing Potential of Some Common Indian Cact' Succulents, Lichens and Aquatic Plants.

    PubMed

    Bhalme, Abhay Y; Pasricha, J S

    1986-01-01

    Irritant potential of 3 cacti, Opuntia dilenii, Rhispalis baccifera and Cereus Peruvians, and 4 succulents, Euphorbia royleana, Euphorbia antiquorum,Sansevieria zeyilanica and Agave sisalana was tested by rubbing their freshly exposed pulp 10 times on the forearm skin of 10 human voluntrees. Opuntia dilenii, Euphorbia antiquorum, Rhispalis baccifera and Agave sisalana produced transitory itching and burning or dermatitis in only one patient each, indicating that these plants are not highly irritant. Patch tests undertaken with the juice, pulp or other components of these plants as well as those of 5 lichens, Parmelia trichotera, Parmelia sulcata, Parmelia quercina, Parmelia furfuracea and Parmelia verrucifera, and 6 aquatic plants Nelumbo nucifera, Eichnornia crassipes, Trapa natans, Anabaena, Salvinia auriculata and Ceratophyllam demeusam in 10 cases each revealed positive reaction with Opuntia Dilenil, Rhispalis baccifera, Cereus Peruvians, Parmelia verrucifera, Nelumbo nucifera, Trapa natans, Salvinia auriculata and Ceratophyllum demeusum in one case each. Agava sisalana and Sensevieria zeylanica in 2 cases each. Euphorbia antiquorym, Parmelia trichotera ' Parmelia quercina, Parmelia furfuracea and Eichhornia crassipes in 3 cases each and Euphorbia royleana and Parmelia sulcata in 4 cases each.

  5. Toxic metals in aquatic plants surviving in surface water polluted by copper mining industry.

    PubMed

    Samecka-Cymerman, A; Kempers, A J

    2004-09-01

    Concentrations of the metals Al, Ba, Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, V, and Zn, as well as the macronutrients N, P, K, Ca, Mg, and S were measured in water, sediments, and the aquatic macrophytes Potamogeton pectinatus and Myriophyllum spicatum, growing in surface water receiving sewages and solid wastes from a copper smelter and a copper ore processing factory located in the Legnica-Glogow copper district in Southwest Poland. The deposition of mineral wastes in this area belong to the largest repository in Europe. The plants were able to survive at heavily contaminated sites. The concentrations of Cd (up to 0.6-1.7 microg/L in water and up to 10.1-12.9 mg/kg in sediments), Cu (up to 29-48 microg/L in water and up to 4.6-5.6g/kg in sediments), Pb (up to 1.5-2.2 g/kg in sediments), and Zn (up to 167-200 microg/L in water and up to 1.4-1.8 g/kg in sediments) seriously exceeded background values. P. pectinatus was able to survive tissue concentrations (in mg/kg) of up to 920 Cu, 6240 Mn, 98 Co, and 59 Ni, while M. spicatum survived tissue concentrations up to 1040 Cu, 6660 Mn, and 57 Co for. Enrichment ratios of elements in plant tissue and in water were much higher than those between plant tissue and sediments.

  6. Does nitrate co-pollution affect biological responses of an aquatic plant to two common herbicides?

    PubMed

    Nuttens, A; Chatellier, S; Devin, S; Guignard, C; Lenouvel, A; Gross, E M

    2016-08-01

    Aquatic systems in agricultural landscapes are subjected to multiple stressors, among them pesticide and nitrate run-off, but effects of both together have rarely been studied. We investigated possible stress-specific and interaction effects using the new OECD test organism, Myriophyllum spicatum, a widespread aquatic plant. In a fully factorial design, we used two widely applied herbicides, isoproturon and mesosulfuron-methyl, in concentration-response curves at two nitrate levels (219.63 and 878.52mg N-NO3). We applied different endpoints reflecting plant performance such as growth, pigment content, content in phenolic compounds, and plant stoichiometry. Relative growth rates based on length (RGR-L) were affected strongly by both herbicides, while effects on relative growth rate based on dry weight (RGR-DW) were apparent for isoproturon but hardly visible for mesosulfuron-methyl due to an increase in dry matter content. The higher nitrate level further reduced growth rates, specifically with mesosulfuron-methyl. Effects were visible between 50 and 500μgL(-1) for isoproturon and 0.5-5μgL(-1) for mesosulfuron-methyl, with some differences between endpoints. The two herbicides had opposite effects on chlorophyll, carotenoid and nitrogen contents in plants, with values increasing with increasing concentrations of isoproturon and decreasing for mesosulfuron-methyl. Herbicides and nitrate level exhibited distinct effects on the content in phenolic compounds, with higher nitrate levels reducing total phenolic compounds in controls and with isoproturon, but not with mesosulfuron-methyl. Increasing concentrations of mesosulfuron-methyl lead to a decline of total phenolic compounds, while isoproturon had little effect. Contents of carbon, nitrogen and phosphorus changed depending on the stressor combination. We observed higher phosphorus levels in plants exposed to certain concentrations of herbicides, potentially indicating a metabolic response. The C:N molar ratio

  7. Removal of high organic loads from winery wastewater by aquatic plants.

    PubMed

    Zimmels, Y; Kirzhner, F; Schreiber, J

    2008-09-01

    Laboratory- and field-scale purification tests of raw and diluted winery wastewater (WWW) were carried out using aquatic plants at high organic loads. The laboratory tests were performed using artificial light at 1800 to 1900 lux. The objective of the current study was to define the potential of floating and emergent aquatic macrophytes and the microorganisms attached to their roots, to reduce high organic loads that characterize WWW, thereby providing, for these effluents, an effective treatment and management system. These microorganisms are believed to have a major role in the treatment process. In this context, the potential of floating and emergent macrophytes to improve the water quality of raw compared with diluted WWW was evaluated. In raw WWW (chemical oxygen demand [COD] 5.6 g/L),growth inhibition of both water hyacinth (Eichhornia crassipes) and water pennywort (Hydrocotyle umbellata) was observed. A 1:1 dilution of WWW with fresh (tap) water facilitated growth of these plants. At this dilution level, growth of pennywort was limited, while that of water hyacinth was robust. In terms of reductions in biochemical oxygen demand, COD, and total suspended solids, both water hyacinth and pennywort performed better in diluted compared with raw WWW. At 1:1 and 1:3 dilution, 95.9 to 97% of the COD was removed after 23 days, in the presence of Hydrocotyle and Eichhornia plants and aeration. The capacity of new emergent plants to remove high organic loads from WWW, at enhanced kinetics, was demonstrated. This unique property was tested and compared with the role of the gravel media that support growth of the high-capacity emergent plants. In the presence of reed and salt marsh plants, 83 to 99% of the COD was removed within a period of 24 to 29 days, at 1.5:1 dilution. The new emergent plants proved to be effective, even at record high levels of COD. At an initial level of 16,460 mg/L, the COD was brought down to 2870 mg/L after 24 days (82.6% removal), while 12

  8. 33 CFR Appendix C to Part 273 - Information Requirements for Aquatic Plant Control Program Environmental Impact Statements

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Aquatic Plant Control Program Environmental Impact Statements C Appendix C to Part 273 Navigation and... Environmental Impact Statements 1. Description of the problem. a. Pests. Identify the pest to be controlled by.... Relationship to environmental situation. Non-target organisms and integrated pest management programs. 2...

  9. Toxicities of Oils, Dispersants and Dispersed Oils to Aquatic Plants: Summary and Database Value to Resource Sustainability

    EPA Science Inventory

    Understanding the phytotoxicities of crude and dispersed oils is important for near-shore ecosystem management, particularly post-oil spills. One source of information is toxicity data summaries which are scattered and outdated for aquatic plants and petrochemicals. As a resu...

  10. UPTAKE AND PHYTOTRANSFORMATION OF O,P'-DDT AND P,P'-DDT BY AXENICALLY CULTIVATED AQUATIC PLANTS

    EPA Science Inventory

    The uptake and phytotransformation of o,p'-DDT and p,p'-DDT were investigated in vitro using three axenically cultivated aquatic plants: parrot feather (Mariophyllum aquaticum), duckweed (Spirodela oligorrhiza), and elodea (Elodea canadensis). The decay profile of DDT from the aq...

  11. Toxicities of Oils, Dispersants and Dispersed Oils to Aquatic Plants: Summary and Database Value to Resource Sustainability

    EPA Science Inventory

    Understanding the phytotoxicities of crude and dispersed oils is important for near-shore ecosystem management, particularly post-oil spills. One source of information is toxicity data summaries which are scattered and outdated for aquatic plants and petrochemicals. As a resu...

  12. 33 CFR Appendix C to Part 273 - Information Requirements for Aquatic Plant Control Program Environmental Impact Statements

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Environmental Impact Statements 1. Description of the problem. a. Pests. Identify the pest to be controlled by... Aquatic Plant Control Program Environmental Impact Statements C Appendix C to Part 273 Navigation and... specifically as possible. c. Severity of infestation. Discuss the degree and importance of the pest problem. d...

  13. 33 CFR Appendix C to Part 273 - Information Requirements for Aquatic Plant Control Program Environmental Impact Statements

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Environmental Impact Statements 1. Description of the problem. a. Pests. Identify the pest to be controlled by... Aquatic Plant Control Program Environmental Impact Statements C Appendix C to Part 273 Navigation and... specifically as possible. c. Severity of infestation. Discuss the degree and importance of the pest problem. d...

  14. UPTAKE AND PHYTOTRANSFORMATION OF O,P'-DDT AND P,P'-DDT BY AXENICALLY CULTIVATED AQUATIC PLANTS

    EPA Science Inventory

    The uptake and phytotransformation of o,p'-DDT and p,p'-DDT were investigated in vitro using three axenically cultivated aquatic plants: parrot feather (Mariophyllum aquaticum), duckweed (Spirodela oligorrhiza), and elodea (Elodea canadensis). The decay profile of DDT from the aq...

  15. Accumulation of perchlorate in aquatic and terrestrial plants at a field scale.

    PubMed

    Tan, Kui; Anderson, Todd A; Jones, Matthew W; Smith, Philip N; Jackson, W Andrew

    2004-01-01

    Previous laboratory-scale studies have documented perchlorate ClO(-)(4) uptake by different plant species, but less information is available at field scale, where ClO(-)(4) uptake may be affected by environmental conditions, such as distance to streams or shallow water tables, exposure duration, and species. This study examined uptake of ClO(-)(4) in smartweed (Polygonum spp.) and watercress (Nasturtium spp.) as well as more than forty trees, including ash (Fraxinus greggii A. Gray), chinaberry (Melia azedarach L.), elm (Ulmus parvifolia Jacq.), willow (Salix nigra Marshall), mulberry [Broussonetia papyrifera (L.) Vent.], and hackberry (Celtis laevigata Willd.) from multiple streams surrounding a perchlorate-contaminated site. Results indicate a large potential for ClO(-)(4) accumulation in aquatic and terrestrial plants, with ClO(-)(4) concentration in plant tissues approximately 100 times higher than that in bulk water. Perchlorate accumulation in leaves of terrestrial plants was also dependent on species, with hackberry, willow, and elm having a strong potential to accumulate ClO(-)(4). Generally, trees located closer to the stream had a higher ClO(-)(4) accumulation than trees located farther away from the stream. Seasonal leaf sampling of terrestrial plants indicated that ClO(-)(4) accumulation also was affected by exposure duration, with highest accumulation observed in the late growing cycle, although leaf concentrations for a given tree were highly variable. Perchlorate may be re-released into the environment via leaching and rainfall as indicated by lower perchlorate concentrations in collected leaf litter. Information obtained from this study will be helpful to understand the fate of ClO(-)(4) in macrophytes and natural systems.

  16. Diversity of Endophytic Fungi Associated with the Roots of Four Aquatic Plants Inhabiting Two Wetlands in Korea.

    PubMed

    You, Young-Hyun; Park, Jong Myong; Park, Jong-Han; Kim, Jong-Guk

    2015-09-01

    A total of 4 aquatic plants, Eleocharis kuroguwai Ohwi, Hydrocharis dubia Backer, Salvinia natans All., and Zizania latifolia Turcz., were sampled from representative two wetlands of South Korea. A total of 38 endophytic fungal strains were isolated from aquatic plants native to the Daepyeong wetland, and 27 strains were isolated from the Jilnal wetland. The internal transcribed spacer regions of fungal isolates were sequenced and a phylogenetic analysis was performed. In addition, endophytic fungal diversity from each wetland and host plant species was deduced. A total of 25 fungal genera were purely isolated, and 16 fungal genera were isolated from each of the two wetlands. Commonly isolated genera from both wetlands were Aspergillus, Cladosporium, Clonostachys, Fusarium, Leptosphaeria, Penicillium, and Talaromyces. This study revealed that fungal diversity varied with environmental conditions and by host plant in representative two wetlands.

  17. Diversity of Endophytic Fungi Associated with the Roots of Four Aquatic Plants Inhabiting Two Wetlands in Korea

    PubMed Central

    You, Young-Hyun; Park, Jong Myong; Park, Jong-Han

    2015-01-01

    A total of 4 aquatic plants, Eleocharis kuroguwai Ohwi, Hydrocharis dubia Backer, Salvinia natans All., and Zizania latifolia Turcz., were sampled from representative two wetlands of South Korea. A total of 38 endophytic fungal strains were isolated from aquatic plants native to the Daepyeong wetland, and 27 strains were isolated from the Jilnal wetland. The internal transcribed spacer regions of fungal isolates were sequenced and a phylogenetic analysis was performed. In addition, endophytic fungal diversity from each wetland and host plant species was deduced. A total of 25 fungal genera were purely isolated, and 16 fungal genera were isolated from each of the two wetlands. Commonly isolated genera from both wetlands were Aspergillus, Cladosporium, Clonostachys, Fusarium, Leptosphaeria, Penicillium, and Talaromyces. This study revealed that fungal diversity varied with environmental conditions and by host plant in representative two wetlands. PMID:26539039

  18. Aquatic Plant Control Research Program: Effects of Water Chemistry on Aquatic Plants: Interrelationships among Biomass Production, Plant Nutrition, and Water Chemistry.

    DTIC Science & Technology

    1988-04-01

    AGE V- - r. ’p. Unclassified SCCURlTY CLASIFICATION OF THIS PAGE I18. SUBJECT TERMS (Continued). Aqua tic plants kydri l Potamogeton...procedures as appropriate (General Linear Models Proce- dure, Statistical Analysis System, Cary , N. C.). Mean comparisons were per- formed using Duncan’s

  19. Multilocus coalescent species delimitation to evaluate traditionally defined morphotypes in Hydrangea sect. Asperae (Hydrangeaceae).

    PubMed

    De Smet, Yannick; De Clerck, Olivier; Uemachi, Tatsuya; Granados Mendoza, Carolina; Wanke, Stefan; Goetghebeur, Paul; Samain, Marie-Stéphanie

    2017-09-01

    The number of species recognized in section Asperae of the flowering plant genus Hydrangea differs widely between subsequent revisions. This variation is largely centered around the H. aspera species complex, with numbers of recognized species varying from one to nearly a dozen. Despite indications of molecular variation in this complex, no sequence-based species delimitation methods have been employed to evaluate the primarily morphology-based species boundaries. In the present study, a multi-locus coalescent-based approach to species delimitation is employed in order to identify separate evolutionary lines within H. sect. Asperae, using four chloroplast and four nuclear molecular markers. Eight lineages were recovered within the focal group, of which five correspond with named morphotypes. The other three lineages illustrate types of conflict between molecular species delimitation and traditional morphology-based taxonomy. One molecular lineage comprises two named morphotypes, which possibly diverged recently enough to not have developed sufficient molecular divergence. A second conflict is found in H. strigosa. This morphotype is recovered as a separate lineage when occurring in geographic isolation, but when occurring in sympatry with two other morphotypes (H. aspera and H. robusta), the coalescent species delimitation lumps these taxa into a single putative species. Copyright © 2017 Elsevier Inc. All rights reserved.

  20. Heavy metals in sediments, soils, and aquatic plants from a secondary anabranch of the three gorges reservoir region, China.

    PubMed

    Gao, Jun-Min; Sun, Xiu-Qian; Jiang, Wen-Chao; Wei, Yun-Mei; Guo, Jin-Song; Liu, Yuan-Yuan; Zhang, Ke

    2016-06-01

    We investigated the occurrence of cadmium (Cd), copper (Cu), chromium (Cr), nickel (Ni), lead (Pb), Znic (Zn), iron (Fe), manganese (Mn), and magnesium (Mg) in sediments, as well as in related soils and aquatic plants in the Liangtan River, a typical secondary anabranch of the Yangtze River in the Three Gorges Reservoir Region (TGRR) of China. We found that sediments accumulated more metals than soils and aquatic plants. Concentrations of the nine metals in sediments and soils followed the same sequence, while their concentrations in aquatic plants followed a different sequence. Potential adverse effects of contaminated sediments on benthic fauna were evaluated, and the results showed that the toxic effect on benthic organisms followed the sequence Zn > Ni > Cr > Cu > Cd > Pb. The potential ecological risk index analysis indicated that Cd in sediments had considerable ecological risk, whereas Cr, Cu, Zn, Ni, and Pb had low ecological risk. The potential ecological risk index (RI) of the heavy metals in sediments of the Liangtan River was 174.9, indicating moderate ecological risk. The transfer factor trend of metals for aquatic plants showed that Cd and Ni had the most and least accumulation, respectively. For Cu, Cd, Mg, Pb, and Cr, a significant positive correlation of the metal concentrations was observed between sediments and soils, but no correlations (excluding Cr) were detected between sediments and aquatic plants. Our study indicated that anthropogenic input may be the primary source of metal contamination in the Liangtan River, and that Zn and Cd pollution in the Liangtan River should be further explored.

  1. Effects of cement flue dust from a cement factory on stress parameters and diversity of aquatic plants.

    PubMed

    Erdal, Serkan; Demirtas, Ayten

    2010-07-01

    Cement kiln dusts, made of a complex mixture of elements, include high levels of heavy metals such as fluoride, magnesium, lead, cadmium, nickel, zinc, copper, beryllium and some toxic compounds. Because of the toxic element compositions and radioactive isotope properties of cement kiln dusts, not only terrestrial but also aquatic ecosystems are subjected to greater stress. In the present paper, we investigated the effects of pollution caused by Askale-Erzurum cement factory (CF) on the stress parameters and diversity of aquatic plants. For this purpose, aquatic plant species were collected from the outer zone of the CF. Only three (Lemna minor, Ceratophyllum submersum and Potamogeton natans) of these species were able to be determined in the CF zone. Antioxidant enzyme activities of the collected aquatic plants were measured and compared to their controls. Superoxide dismutase (SOD) activity of P. natans in the CF zone was significantly high compared to their respective control, while it was low in L. minor and C. submersum compared to their controls. Similarly, peroxidase (POX) activity of P. natans was high, while those of L. minor and C. submersum were low compared to their respective controls. On the other side, while catalase (CAT) activities of L. minor and C. submersum were low, that of P. natans did not show an important change compared to their respective controls. Furthermore, we found that hydrogen peroxide (H(2)O(2)) and malondialdehyde (MDA) levels of all the studied plants were also very high compared to their controls. According to these results, it is clear that pollution caused by the CF reduced diversity and number of aquatic plant species. Besides, the obtained data revealed that P. natans have a more resistant defense system than other species.

  2. Phytoliths in taxonomy of phylogenetic domains of plants.

    PubMed

    Golokhvast, Kirill S; Seryodkin, Ivan V; Chaika, Vladimir V; Zakharenko, Alexander M; Pamirsky, Igor E

    2014-01-01

    We discuss, from the aspect of phylogeny, the interrelationships of the phytolith types in plants from the main taxonomical groups (algae, lichens, horsetails, gymnosperms, and floral plants) with homologues of known proteins of biomineralization. Phytolith morphotypes in various phylogenetic plant domains have different shapes. We found that, in ancient types of plants (algae, horsetails, and gymnosperms), there are fewer different phytolith morphotypes compared to more modern plants (floral plants). The phytolith morphotypes in primitive plants are generally larger than the morphotypes in more highly organized plants. We found that the irregular ruminate and irregular smooth morphotypes are the two most frequently encountered phytolith morphotypes in the tested plants (from algae to floral plants). These two morphotypes probably have a universal role. Silacidins, silicon transporters, silicateins, silaffins, and silicase homologues are often found in the major taxonomic groups of plants. Red algae had the smallest number of homologues of the biomineralization proteins (70-80), Monocotyledonous: 142, Coniferous: 166, Mosses: 227, and Dicotyledones: 336.

  3. Relationships among three pathways for resource acquisition and their contribution to plant performance in the emergent aquatic Plant Lythrum salicaria (L.).

    PubMed

    Stevens, K J; Peterson, R L

    2007-11-01

    Three pathways for resource acquisition exist in the emergent aquatic plant, Lythrum salicaria (L.); a subterranean root system, a free-floating adventitious root system, and arbuscular mycorrhiza (AM) fungal hyphae colonizing subterranean roots. This study examined the relationship(s) among these pathways and their contribution to plant performance. If the free-floating adventitious root system and/or AM fungi contribute to plant growth in wetland habitats, we predicted that their absence would result in a significant reduction in plant performance. Furthermore, if a reduction in resource uptake, effected by an absence of free-floating adventitious roots and/or AM fungi, is compensated for by increased allocation to remaining pathway(s) for resource uptake, we predicted altered patterns of resource allocation among shoots and the remaining pathway(s) for resource uptake. Contrary to our predications, plants experiencing adventitious root removal and/or grown in the absence of AM fungi generally had greater biomass and total shoot height than controls. Similarly, while levels of AM colonization and subterranean root biomass displayed a treatment effect, the observed responses did not correspond with our predictions. This was also true for shoot : subterranean root dry weight ratios. Our results indicate that there is interaction among the 3 pathways for resource acquisition in L. salicaria and an effect on plant performance. The adaptive significance of these characteristics is unclear, highlighting the potential difficulties in extrapolating from terrestrial to aquatic plant species and among aquatic plant species with potentially different life history strategies.

  4. Clonal plasticity of aquatic plant species submitted to mechanical stress: escape versus resistance strategy.

    PubMed

    Puijalon, Sara; Bouma, Tjeerd J; van Groenendael, Jan; Bornette, Gudrun

    2008-12-01

    The plastic alterations of clonal architecture are likely to have functional consequences, as they affect the spatial distribution of ramets over patchy environments. However, little is known about the effect of mechanical stresses on the clonal growth. The aim of the present study was to investigate the clonal plasticity induced by mechanical stress consisting of continuous water current encountered by aquatic plants. More particularly, the aim was to test the capacity of the plants to escape this stress through clonal plastic responses. The transplantation of ramets of the same clone in two contrasting flow velocity conditions was carried out for two species (Potamogeton coloratus and Mentha aquatica) which have contrasting clonal growth forms. Relative allocation to clonal growth, to creeping stems in the clonal biomass, number and total length of creeping stems, spacer length and main creeping stem direction were measured. For P. coloratus, plants exposed to water current displayed increased total length of creeping stems, increased relative allocation to creeping stems within the clonal dry mass and increased spacer length. For M. aquatica, plants exposed to current displayed increased number and total length of creeping stems. Exposure to current induced for both species a significant increase of the proportion of creeping stems in the downstream direction to the detriment of creeping stems perpendicular to flow. This study demonstrates that mechanical stress from current flow induced plastic variation in clonal traits for both species. The responses of P. coloratus could lead to an escape strategy, with low benefits with respect to sheltering and anchorage. The responses of M. aquatica that may result in a denser canopy and enhancement of anchorage efficiency could lead to a resistance strategy.

  5. Clonal Plasticity of Aquatic Plant Species Submitted to Mechanical Stress: Escape versus Resistance Strategy

    PubMed Central

    Puijalon, Sara; Bouma, Tjeerd J.; Van Groenendael, Jan; Bornette, Gudrun

    2008-01-01

    Background and Aims The plastic alterations of clonal architecture are likely to have functional consequences, as they affect the spatial distribution of ramets over patchy environments. However, little is known about the effect of mechanical stresses on the clonal growth. The aim of the present study was to investigate the clonal plasticity induced by mechanical stress consisting of continuous water current encountered by aquatic plants. More particularly, the aim was to test the capacity of the plants to escape this stress through clonal plastic responses. Methods The transplantation of ramets of the same clone in two contrasting flow velocity conditions was carried out for two species (Potamogeton coloratus and Mentha aquatica) which have contrasting clonal growth forms. Relative allocation to clonal growth, to creeping stems in the clonal biomass, number and total length of creeping stems, spacer length and main creeping stem direction were measured. Key Results For P. coloratus, plants exposed to water current displayed increased total length of creeping stems, increased relative allocation to creeping stems within the clonal dry mass and increased spacer length. For M. aquatica, plants exposed to current displayed increased number and total length of creeping stems. Exposure to current induced for both species a significant increase of the proportion of creeping stems in the downstream direction to the detriment of creeping stems perpendicular to flow. Conclusions This study demonstrates that mechanical stress from current flow induced plastic variation in clonal traits for both species. The responses of P. coloratus could lead to an escape strategy, with low benefits with respect to sheltering and anchorage. The responses of M. aquatica that may result in a denser canopy and enhancement of anchorage efficiency could lead to a resistance strategy. PMID:18854376

  6. Multiple mitigation mechanisms: Effects of submerged plants on the toxicity of nine insecticides to aquatic animals.

    PubMed

    Brogan, William R; Relyea, Rick A

    2017-01-01

    Understanding the processes that regulate contaminant impacts in nature is an increasingly important challenge. For insecticides in surface waters, the ability of aquatic plants to sorb, or bind, hydrophobic compounds has been identified as a primary mechanism by which toxicity can be mitigated (i.e. the sorption-based model). However, recent research shows that submerged plants can also rapidly mitigate the toxicity of the less hydrophobic insecticide malathion via alkaline hydrolysis (i.e. the hydrolysis-based model) driven by increased water pH resulting from photosynthesis. However, it is still unknown how generalizable these mitigation mechanisms are across the wide variety of insecticides applied today, and whether any general rules can be ascertained about which types of chemicals may be mitigated by each mechanism. We quantified the degree to which the submerged plant Elodea canadensis mitigated acute (48-h) toxicity to Daphnia magna using nine commonly applied insecticides spanning three chemical classes (carbamates: aldicarb, carbaryl, carbofuran; organophosphates: malathion, diazinon, chlorpyrifos; pyrethroids: permethrin, bifenthrin, lambda-cyhalothrin). We found that insecticides possessing either high octanol-water partition coefficients (log Kow) values (i.e. pyrethroids) or high susceptibility to alkaline hydrolysis (i.e. carbamates and malathion) were all mitigated to some degree by E. canadensis, while the plant had no effect on insecticides possessing intermediate log Kow values and low susceptibility to hydrolysis (i.e. chlorpyrifos and diazinon). Our results provide the first general insights into which types of insecticides are likely to be mitigated by different mechanisms based on known chemical properties. We suggest that current models and mitigation strategies would be improved by the consideration of both mitigation models.

  7. The role of hybridization in the evolution of sexual system diversity in a clonal, aquatic plant.

    PubMed

    Yakimowski, Sarah B; Barrett, Spencer C H

    2016-06-01

    The stable coexistence within populations of females, males, and hermaphrodites (subdioecy) is enigmatic because theoretical models indicate that maintenance of this sexual system involves highly restricted conditions. Subdioecy is more commonly interpreted as a transitory stage along the gynodioecious pathway from hermaphroditism to dioecy. The widespread, North American, aquatic plant Sagittaria latifolia is largely composed of monoecious or dioecious populations; however, subdioecious populations with high frequencies of hermaphrodites (mean frequency = 0.50) characterize the northern range boundary of dioecy in eastern North America. We investigated two hypotheses for the origin of subdioecy in this region. Using polymorphic microsatellite loci, we evaluated whether subdioecy arises through selection on standing genetic variation for male sex inconstancy in dioecious populations, or results from hybridization between monoecious and dioecious populations. We found evidence for both pathways to subdioecy, although hybridization was the more common mechanism, with genetic evidence of admixture in nine of 14 subdioecious populations examined. Hybridization has also played a role in the origin of androdioecious populations in S. latifolia, a mechanism not often considered in the evolution of this rare sexual system. Our study demonstrates how hybridization has the potential to play a role in the diversification of plant sexual systems. © 2016 The Author(s). Evolution © 2016 The Society for the Study of Evolution.

  8. Hydrologic alteration affects aquatic plant assemblages in an arid-land river

    USGS Publications Warehouse

    Vinson, Mark; Hestmark, Bennett; Barkworth, Mary E.

    2014-01-01

    We evaluated the effects of long-term flow alteration on primary-producer assemblages. In 1962, Flaming Gorge Dam was constructed on the Green River. The Yampa River has remained an unregulated hydrologically variable river that joins the Green River 100 km downstream from Flaming Gorge Dam. In the 1960s before dam construction only sparse occurrences of two macroalgae, Cladophora and Chara, and no submerged vascular plants were recorded in the Green and Yampa rivers. In 2009–2010, aquatic plants were abundant and widespread in the Green River from the dam downstream to the confluence with the Yampa River. The assemblage consisted of six vascular species, Elodea canadensis, Myriophyllum sibiricum, Nasturtium officinale,Potamogeton crispus, Potamogeton pectinatus, and Ranunculus aquatilis, the macroalgae Chara and Cladophora, and the bryophyte, Amblystegium riparium. In the Green River downstream from the Yampa River, and in the Yampa River, only sparse patches of Chara and Cladophora growing in the splash zone on boulders were collected. We attribute the observed changes in the Green River to an increase in water transparency and a reduction in suspended and bed-load sediment and high flow disturbances. The lack of hydrophyte colonization downstream from the confluence with the Yampa River has implications for understanding tributary amelioration of dam effects and for designing more natural flow-regime schedules downstream from large dams.

  9. Ants swimming in pitcher plants: kinematics of aquatic and terrestrial locomotion in Camponotus schmitzi.

    PubMed

    Bohn, Holger Florian; Thornham, Daniel George; Federle, Walter

    2012-06-01

    Camponotus schmitzi ants live in symbiosis with the Bornean pitcher plant Nepenthes bicalcarata. Unique among ants, the workers regularly dive and swim in the pitcher's digestive fluid to forage for food. High-speed motion analysis revealed that C. schmitzi ants swim at the surface with all legs submerged, with an alternating tripod pattern. Compared to running, swimming involves lower stepping frequencies and larger phase delays within the legs of each tripod. Swimming ants move front and middle legs faster and keep them more extended during the power stroke than during the return stroke. Thrust estimates calculated from three-dimensional leg kinematics using a blade-element approach confirmed that forward propulsion is mainly achieved by the front and middle legs. The hind legs move much less, suggesting that they mainly serve for steering. Experiments with tethered C. schmitzi ants showed that characteristic swimming movements can be triggered by submersion in water. This reaction was absent in another Camponotus species investigated. Our study demonstrates how insects can use the same locomotory system and similar gait patterns for moving on land and in water. We discuss insect adaptations for aquatic/amphibious lifestyles and the special adaptations of C. schmitzi to living on an insect-trapping pitcher plant.

  10. Removal of lead ions from aqueous solution by the dried aquatic plant, Lemna perpusilla Torr.

    PubMed

    Tang, Yankui; Chen, Ling; Wei, Xingren; Yao, Qiuyan; Li, Ting

    2013-01-15

    The aquatic plant, Lemna perpusilla Torr. strain, was dried, pulverized and used for Pb(II) removal from aqueous solution. Batch experiments were conducted to investigate the effects of pH, contact time, initial metal concentration and temperature on Pb(II) adsorption. A dose of 4 g L(-1) of dried L. perpusilla in a solution with an initial pH of 4.6, an initial Pb(II) concentration of 50 mg L(-1) and a contact time of 210 min resulted in the maximum Pb(II) removal efficiency (above 95%). The equilibrium adsorption capacities increased with increasing initial Pb(II) concentration. The adsorption isotherm was better described by a Langmuir model rather than a Freundlich model. Further, the adsorption kinetics followed a pseudo-second-order model. An FTIR examination revealed changes between the natural and Pb(II)-loaded plant material. Scanning electron micrograph (SEM) also revealed changes in the surface morphology of the biomass as a result of lead adsorption. Based on these results, it can be concluded that the dried L. perpusilla is effective in removing lead from aqueous solution and merits consideration for scaled-up trials.

  11. Laboratory tests for the phytoextraction of heavy metals from polluted harbor sediments using aquatic plants.

    PubMed

    Mânzatu, Carmen; Nagy, Boldizsár; Ceccarini, Alessio; Iannelli, Renato; Giannarelli, Stefania; Majdik, Cornelia

    2015-12-30

    The aim of this study was to investigate the concentrations and pollution levels of heavy metals, organochlorine pesticides, and polycyclic aromatic hydrocarbons in marine sediments from the Leghorn Harbor (Italy) on the Mediterranean Sea. The phytoextraction capacity of three aquatic plants Salvinia natans, Vallisneria spiralis, and Cabomba aquatica was also tested in the removal of lead and copper, present in high concentration in these sediments. The average detectable concentrations of metals accumulated by the plants in the studied area were as follows: >3.328 ± 0.032 mg/kg dry weight (DW) of Pb and 2.641 ± 0.014 mg/kg DW of Cu for S. natans, >3.107 ± 0.034 g/kg DW for V. spiralis, and >2.400 ± 0.029 mg/kg DW for C. aquatica. The occurrence of pesticides was also analyzed in the sediment sample by gas chromatography coupled with mass spectrometry (GC/MS). Due to its metal and organic compound accumulation patterns, S. natans is a potential candidate in phytoextraction strategies.

  12. Responses of Ottelia alismoides, an aquatic plant with three CCMs, to variable CO2 and light.

    PubMed

    Shao, Hui; Gontero, Brigitte; Maberly, Stephen C; Jiang, Hong Sheng; Cao, Yu; Li, Wei; Huang, Wen Min

    2017-06-01

    Ottelia alismoides is a constitutive C4 plant and bicarbonate user, and has facultative crassulacean acid metabolism (CAM) at low CO2. Acclimation to a factorial combination of light and CO2 showed that the ratio of phosphoenolpyruvate carboxylase (PEPC) to ribulose-bisphosphate carboxylase/oxygenase (Rubisco) (>5) is in the range of that of C4 plants. This and short-term response experiments showed that the activity of PEPC and pyruvate phosphate dikinase (PPDK) was high even at the end of the night, consistent with night-time acid accumulation and daytime carbon fixation. The diel acidity change was maximal at high light and low CO2 at 17-25 µequiv g-1 FW. Decarboxylation proceeded at ~2-3 µequiv g-1 FW h-1, starting at the beginning of the photoperiod, but did not occur at high CO2; the rate was greater at high, compared with low light. There was an inverse relationship between starch formation and acidity loss. Acidity changes account for up to 21% of starch production and stimulate early morning photosynthesis, but night-time accumulation of acid traps <6% of respiratory carbon release. Ottelia alismoides is the only known species to operate CAM and C4 in the same tissue, and one of only two known aquatic species to operate CAM and bicarbonate use. © The Author 2017. Published by Oxford University Press on behalf of the Society for Experimental Biology.

  13. Uptake of uranium by aquatic plants growing in fresh water ecosystem around uranium mill tailings pond at Jaduguda, India.

    PubMed

    Jha, V N; Tripathi, R M; Sethy, N K; Sahoo, S K

    2016-01-01

    Concentration of uranium was determined in aquatic plants and substrate (sediment or water) of fresh water ecosystem on and around uranium mill tailings pond at Jaduguda, India. Aquatic plant/substrate concentration ratios (CRs) of uranium were estimated for different sites on and around the uranium mill tailings disposal area. These sites include upstream and downstream side of surface water sources carrying the treated tailings effluent, a small pond inside tailings disposal area and residual water of this area. Three types of plant groups were investigated namely algae (filamentous and non-filamentous), other free floating & water submerged and sediment rooted plants. Wide variability in concentration ratio was observed for different groups of plants studied. The filamentous algae uranium concentration was significantly correlated with that of water (r=0.86, p<0.003). For sediment rooted plants significant correlation was found between uranium concentration in plant and the substrate (r=0.88, p<0.001). Both for other free floating species and sediment rooted plants, uranium concentration was significantly correlated with Mn, Fe, and Ni concentration of plants (p<0.01). Filamentous algae, Jussiaea and Pistia owing to their high bioproductivity, biomass, uranium accumulation and concentration ratio can be useful for prospecting phytoremediation of stream carrying treated or untreated uranium mill tailings effluent. Copyright © 2015 Elsevier B.V. All rights reserved.

  14. Toxicities of oils, dispersants and dispersed oils to algae and aquatic plants: review and database value to resource sustainability.

    PubMed

    Lewis, Michael; Pryor, Rachel

    2013-09-01

    Phytotoxicity results are reviewed for oils, dispersants and dispersed oils. The phytotoxicity database consists largely of results from a patchwork of reactive research conducted after oil spills to marine waters. Toxicity information is available for at least 41 crude oils and 56 dispersants. As many as 107 response parameters have been monitored for 85 species of unicellular and multicellular algae, 28 wetland plants, 13 mangroves and 9 seagrasses. Effect concentrations have varied by as much as six orders of magnitude due to experimental diversity. This diversity restricts phytotoxicity predictions and identification of sensitive species, life stages and response parameters. As a result, evidence-based risk assessments for most aquatic plants and petrochemicals and dispersants are not supported by the current toxicity database. A proactive and experimentally-consistent approach is recommended to provide threshold toxic effect concentrations for sensitive life stages of aquatic plants inhabiting diverse ecosystems. Published by Elsevier Ltd.

  15. Uptake and Distribution of Silver in the Aquatic Plant Landoltia punctata (Duckweed) Exposed to Silver and Silver Sulfide Nanoparticles.

    PubMed

    Stegemeier, John P; Colman, Benjamin P; Schwab, Fabienne; Wiesner, Mark R; Lowry, Gregory V

    2017-05-02

    Aquatic ecosystems are expected to receive Ag(0) and Ag2S nanoparticles (NPs) through anthropogenic waste streams. The speciation of silver in Ag-NPs affects their fate in ecosystems, but its influence on interactions with aquatic plants is still unclear. Here, the Ag speciation and distribution was measured in an aquatic plant, duckweed (Landoltia punctata), exposed to Ag(0) or Ag2S NPs, or to AgNO3. The silver distribution in duckweed roots was visualized using synchrotron-based micro X-ray fluorescence (XRF) mapping and Ag speciation was determined using extended X-ray absorption fine structure (EXAFS) spectroscopy. Duckweed exposed to Ag2S-NPs or Ag(0)-NPs accumulated similar Ag concentrations despite an order of magnitude smaller dissolved Ag fraction measured in the exposure medium for Ag2S-NPs compared to Ag(0)-NPs. By 24 h after exposure, all three forms of silver had accumulated on and partially in the roots regardless of the form of Ag exposed to the plants. Once associated with duckweed tissue, Ag(0)-NPs had transformed primarily into silver sulfide and silver thiol species. This suggests that plant defenses were active within or at the root surface. The Ag2S-NPs remained as Ag2S, while AgNO3 exposure led to Ag(0) and sulfur-associated Ag species in plant tissue. Thus, regardless of initial speciation, Ag was readily available to duckweed.

  16. Carbon isotopes in aquatic plants, Long Valley Caldera, California as records of past hydrothermal and magmatic activity

    NASA Astrophysics Data System (ADS)

    Reid, John B., Jr.; Reynolds, Jesse L.; Connolly, Nathan T.; Getz, Shari L.; Polissar, Pratigya J.; Winship, Lawrence J.; Hainsworth, Laura J.

    Hot and cold springs contribute “dead” (14C free) dissolved inorganic carbon (DIC) to the Owens River and Hot Creek. Headwaters aquatic plants have modern 14C, but live plants downstream of the intracaldera springs are depleted in 14C, (as low as 19% modern, with apparent ages up to 13.3 kyrs). In an abandoned meander of the upper Owens River, preserved streambed plants are buried by 600 year old Inyo Craters pumice. Apparent 14C ages of these plants exceed true ages by ∼ 1100 years indicating that they also incorporated dead DIC as they grew. The preserved plants are downstream of Big Springs, whose elevated dead DIC may represent magmatic ‘CO2. The buried plants incorporated ∼10% dead carbon, although modern plants here have ∼50% dead carbon, suggesting that more magmatic CO2 is now entering the upper Owens River than at the time of the Inyo Craters eruptions 600 years ago.

  17. EXOTIC AND INVASIVE AQUATIC PLANTS IN GREAT LAKES COASTAL WETLANDS: DISTRIBUTION AND RELATION TO WATERSHED LAND USE AND PLANT RICHNESS AND COVER

    EPA Science Inventory

    This manuscript provides previously unavailable information to researchers and managers concerning exotic plants in the Great Lakes...This work arises out of our broader efforts to describe biota - habitat relationships in coastal wetlands, and as such falls under Aquatic Stresso...

  18. EXOTIC AND INVASIVE AQUATIC PLANTS IN GREAT LAKES COASTAL WETLANDS: DISTRIBUTION AND RELATION TO WATERSHED LAND USE AND PLANT RICHNESS AND COVER

    EPA Science Inventory

    This manuscript provides previously unavailable information to researchers and managers concerning exotic plants in the Great Lakes...This work arises out of our broader efforts to describe biota - habitat relationships in coastal wetlands, and as such falls under Aquatic Stresso...

  19. IS THE TIER-1 EFFECT ASSESSMENT FOR HERBICIDES PROTECTIVE FOR AQUATIC ALGAE AND VASCULAR PLANT COMMUNITIES?

    PubMed

    Van Wijngaarden, René P A; Arts, Gertie H P

    2017-08-08

    In the aquatic Tier-1 effect assessment for plant protection products with a herbicidal mode of action in Europe, it is usually algae and/or vascular plants that determine the environmental risks. This tier includes tests with at least two algae and one macrophyte (Lemna). Although considered of a chronic nature based on the duration of the test in relation to the life cycle of the organism, the measurement endpoints that are derived from the laboratory tests with plants (including algae) and used in the first tier effect assessment for herbicides are acute effect concentrations affecting 50% of the test organisms (EC50 values) and not NOEC or EC10 values. Other European legislative frameworks (e.g. the Water Framework Directive) use effect concentrations affecting 10% of the test organisms (EC10 values). This paper contributes to a validation of the tiered herbicide risk assessment approach by comparing the standard first-tier effect assessment with results of microcosm and mesocosm studies. We evaluated EC50 and EC10 values for standard test algae and macrophytes based on either the growth rate endpoint (Er C50 ) or the lowest available endpoint for growth rate or biomass/yield (Er/EyC50). These values were compared with the Regulatory Acceptable Concentrations (RACs) for the threshold option as derived from microcosm and mesocosm studies. For these studies, protection is maintained if "growth rate" is taken as the regulatory endpoint instead of the lowest value of either "growth rate" or "biomass/yield" in conjunction with the standard Assessment Factor of 10. We conclude that based on a limited data set of 14 herbicides, no need was identified to change the current practice. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  20. Actual versus predicted impacts of three ethanol plants on aquatic and terrestrial resources

    SciTech Connect

    Eddlemon, G.K.; Webb, J.W.; Hunsaker, D.B. Jr.; Miller, R.L.

    1993-03-15

    To help reduce US dependence on imported petroleum, Congress passed the Energy Security Act of 1980 (public Law 96-294). This legislation authorized the US Department of Energy (DOE) to promote expansion of the fuel alcohol industry through, among other measures, its Alcohol Fuels Loan Guarantee Program. Under this program, selected proposals for the conversion of plant biomass into fuel-grade ethanol would be granted loan guarantees. of 57 applications submitted for loan guarantees to build and operate ethanol fuel projects under this program, 11 were considered by DOE to have the greatest potential for satisfying DOE`s requirements and goals. In accordance with the National Environmental Policy Act (NEPA), DOE evaluated the potential impacts of proceeding with the Loan Guarantee Program in a programmatic environmental assessment (DOE 1981) that resulted in a finding of no significant impact (FANCY) (47 Federal Register 34, p. 7483). The following year, DOE conducted site-specific environmental assessments (EAs) for 10 of the proposed projects. These F-As predicted no significant environmental impacts from these projects. Eventually, three ethanol fuel projects received loan guarantees and were actually built: the Tennol Energy Company (Tennol; DOE 1982a) facility near Jasper in southeastern Tennessee; the Agrifuels Refining Corporation (Agrifuels; DOE 1985) facility near New Liberia in southern Louisiana; and the New Energy Company of Indiana (NECI; DOE 1982b) facility in South Bend, Indiana. As part of a larger retrospective examination of a wide range of environmental effects of ethanol fuel plants, we compared the actual effects of the three completed plants on aquatic and terrestrial resources with the effects predicted in the NEPA EAs several years earlier. A secondary purpose was to determine: Why were there differences, if any, between actual effects and predictions? How can assessments be improved and impacts reduced?

  1. Cytokinin, auxin and physiological polarity in the aquatic carnivorous plants Aldrovanda vesiculosa and Utricularia australis

    PubMed Central

    Šimura, Jan; Spíchal, Lukáš; Adamec, Lubomír; Pěnčík, Aleš; Rolčík, Jakub; Novák, Ondřej; Strnad, Miroslav

    2016-01-01

    Background and Aims The typical rootless linear shoots of aquatic carnivorous plants exhibit clear, steep polarity associated with very rapid apical shoot growth. The aim of this study was to determine how auxin and cytokinin contents are related to polarity and shoot growth in such plants. Methods The main auxin and cytokinin metabolites in separated shoot segments and turions of two carnivorous plants, Aldrovanda vesiculosa and Utricularia australis, were analysed using ultra-high-performance liquid chromatography coupled with triple quad mass spectrometry. Key Results In both species, only isoprenoid cytokinins were identified. Zeatin cytokinins predominated in the apical parts, with their concentrations decreasing basipetally, and the trans isomer predominated in A. vesiculosa whereas the cis form was more abundant in U australis. Isopentenyladenine-type cytokinins, in contrast, increased basipetally. Conjugated cytokinin metabolites, the O-glucosides, were present at high concentrations in A. vesiculosa but only in minute amounts in U. australis. N9-glucoside forms were detected only in U. australis, with isopentenyladenine-9-glucoside (iP9G) being most abundant. In addition to free indole-3-acetic acid (IAA), indole-3-acetamide (IAM), IAA-aspartate (IAAsp), IAA-glutamate (IAGlu) and IAA-glycine (IAGly) conjugates were identified. Conclusions Both species show common trends in auxin and cytokinin levels, the apical localization of the cytokinin biosynthesis and basipetal change in the ratio of active cytokinins to auxin, in favour of auxin. However, our detailed study of cytokinin metabolic profiles also revealed that both species developed different regulatory mechanisms of active cytokinin content; on the level of their degradation, in U. australis, or in the biosynthesis itself, in the case of A. vesiculosa. Results indicate that the rapid turnover of these signalling molecules along the shoots is essential for maintaining the dynamic balance between the

  2. Aquatic humic substances inhibit clastogenic events in germinating seeds of herbaceous plants.

    PubMed

    Ferrara, G; Loffredo, E; Senesi, N

    2001-03-01

    One humic acid (HA) and two fulvic acids (FAs) of aquatic origin have been tested for their capacity to inhibit clastogenic events caused by maleic hydrazide (MH) in germinating seeds of the herbaceous plant species Allium cepa and Vicia faba. Either HA or FA at concentrations of 50 and 500 mg L(-)(1) was interacted with 10 mg L(-)(1) MH for 24 h before addition to the seeds. The evaluation of genotoxic activity was made by counting micronuclei (MN) and aberrant anatelophases (AT) in root tip cells after treatment with HA or FA alone, MH alone, and interacted HA + MH and FA + MH. Regular AT were also counted as an index of mitotic activity. In all cases HA and FA interacted with MH showed an evident anticlastogenic action indicated by the marked reduction of genetic anomalies. In A. cepa, the anticlastogenic effect of HA and FA was more significant for aberrant AT than for MN, whereas the opposite was true in the case of V. faba. The protective effect exhibited for both anomalies by HA was slightly higher than that of the corresponding FA in A. cepa, whereas no significant differences between these HA and FA treatments were observed in the case of V. faba. The two FAs generally showed similar anticlastogenic behaviors with slight quantitative differences observed as a function of the type of anomaly and the plant species. The effects of HA and FA concentration differed depending on the type of anomaly observed, the plant species, and FA origin. In V. faba, cell division, that is, the number of regular AT, was generally depressed by HA and FA at either concentration with respect to the control. In A. cepa, HA and FA produced either stimulating or inhibiting effects on regular AT depending on their nature, origin, and concentration.

  3. Comparative radiocarbon dating of terrestrial plant macrofossils and aquatic moss from the “ice-free corridor” of western Canada

    NASA Astrophysics Data System (ADS)

    MacDonald, G. M.; Beukens, R. P.; Kieser, W. E.; Vitt, D. H.

    1987-09-01

    In order to assess the reliability of aquatic moss for radiocarbon dating, 14C analyses were performed on a stratigraphic series of terrestrial plant macrofossils and samples of Drepanocladus crassicostatus from a small, hard-water lake (pH = 8.2) in the “ice-free corridor” of Alberta. All 14C dating was done by using accelerator mass spectrometry. Mazama Ash provided an independent chronological control. The aquatic bryophyte samples consistently produced 14C ages significantly older than the terrestrial macrofossils. The relation between the radiocarbon dates from the macrofossils and the moss was not linear, and age differences ranged from approximately 1400 to 6400 yr. The 14C content of D. crassicostatus growing in the lake at present was less than 85% modern. Despite the apparent inability to take up 14C-deficient carbon by the direct incorporation of bicarbonate, the bryophytes clearly do not provide reliable material for 14C dating. The 14C deficiency of aquatic mosses may be explained by the generation of 14C-deficient CO2 through isotopic exchange, the formation of CO2 from bicarbonate by chemical processes, and metabolic CO2 production. These results demonstrate the potential unreliability of 14C dates from aquatic mosses and raise serious concerns about the deglaciation dates from the ice-free corridor that were obtained from aquatic Drepanocladus.

  4. Comparative radiocarbon dating of terrestrial plant macrofossils and aquatic moss from the ice-free corridor of western Canada

    SciTech Connect

    MacDonald, G.M.; Beukens, R.P.; Kieser, W.E.; Vitt, D.H.

    1987-09-01

    In order to assess the reliability of aquatic moss for radiocarbon dating, /sup 14/C analyses were performed on a stratigraphic series of terrestrial plant macrofossils and samples of Drepanocladus crassicostatus from a small, hard-water lake (pH = 8.2) in the ice-free corridor of Alberta. All /sup 14/C dating was done by using accelerator mass spectrometry. Mazama Ash provided an independent chronological control. The aquatic bryophyte samples consistently produced /sup 14/C ages significantly older than the terrestrial macrofossils. The relation between the radiocarbon dates from the macrofossils and the moss was not linear, and age differences ranged from approximately 1400 to 6400 yr. The /sup 14/C content of D. crassicostatus growing in the lake at present was less than 85% modern. Despite the apparent inability to take up /sup 14/C-deficient carbon by the direct incorporation of bicarbonate, the bryophytes clearly do not provide reliable material /sup 14/C dating. The /sup 14/C deficiency of aquatic mosses may be explained by the generation of /sup 14/C-deficient CO/sub 2/ through isotopic exchange, the formation of CO/sub 2/ from bicarbonate by chemical processes, and metabolic CO/sub 2/ production. These results demonstrate the potential unreliability of /sup 14/C dates from aquatic mosses and raise serious concerns about the deglaciation dates from the ice-free corridor that were obtained from aquatic Drepanocladus.

  5. Comparative bioenergetics modeling of two Lake Trout morphotypes

    USGS Publications Warehouse

    Kepler, Megan V.; Wagner, Tyler; Sweka, John A.

    2014-01-01

    Efforts to restore Lake Trout Salvelinus namaycush in the Laurentian Great Lakes have been hampered for decades by several factors, including overfishing and invasive species (e.g., parasitism by Sea Lampreys Petromyzon marinus and reproductive deficiencies associated with consumption of Alewives Alosa pseudoharengus). Restoration efforts are complicated by the presence of multiple body forms (i.e., morphotypes) of Lake Trout that differ in habitat utilization, prey consumption, lipid storage, and spawning preferences. Bioenergetics models constitute one tool that is used to help inform management and restoration decisions; however, bioenergetic differences among morphotypes have not been evaluated. The goal of this research was to investigate bioenergetic differences between two actively stocked morphotypes: lean and humper Lake Trout. We measured consumption and respiration rates across a wide range of temperatures (4–22°C) and size-classes (5–100 g) to develop bioenergetics models for juvenile Lake Trout. Bayesian estimation was used so that uncertainty could be propagated through final growth predictions. Differences between morphotypes were minimal, but when present, the differences were temperature and weight dependent. Basal respiration did not differ between morphotypes at any temperature or size-class. When growth and consumption differed between morphotypes, the differences were not consistent across the size ranges tested. Management scenarios utilizing the temperatures presently found in the Great Lakes (e.g., predicted growth at an average temperature of 11.7°C and 14.4°C during a 30-d period) demonstrated no difference in growth between the two morphotypes. Due to a lack of consistent differences between lean and humper Lake Trout, we developed a model that combined data from both morphotypes. The combined model yielded results similar to those of the morphotype-specific models, suggesting that accounting for morphotype differences may

  6. Mycobacterium abscessus Morphotype Comparison in a Murine Model

    PubMed Central

    Caverly, Lindsay J.; Caceres, Silvia M.; Fratelli, Cori; Happoldt, Carrie; Kidwell, Kelley M.; Malcolm, Kenneth C.; Nick, Jerry A.; Nichols, David P.

    2015-01-01

    Pulmonary infections with Mycobacterium abscessus (M. abscessus) are increasingly prevalent in patients with lung diseases such as cystic fibrosis. M. abscessus exists in two morphotypes, smooth and rough, but the impact of morphotype on virulence is unclear. We developed an immune competent mouse model of pulmonary M. abscessus infection and tested the differences in host inflammatory response between the morphotypes of M. abscessus. Smooth and rough morphotypes of M. abscessus were isolated from the same American Type Culture Collection strain. Wild type and cystic fibrosis mice were intratracheally inoculated with known quantities of M. abscessus suspended in fibrin plugs. At the time of sacrifice lung and splenic tissues and bronchoalveolar lavage fluid were collected and cultured. Bronchoalveolar lavage fluid was analyzed for leukocyte count, differential and cytokine expression. Pulmonary infection with M. abscessus was present at both 3 days and 14 days post-inoculation in all groups at greater levels than systemic infection. Inoculation with M. abscessus rough morphotype resulted in more bronchoalveolar lavage fluid neutrophils compared to smooth morphotype at 14 days post-inoculation in both wild type (p = 0.01) and cystic fibrosis (p<0.01) mice. Spontaneous in vivo conversion from smooth to rough morphotype occurred in 12/57 (21%) of mice. These mice trended towards greater weight loss than mice in which morphotype conversion did not occur. In the described fibrin plug model of M. abscessus infection, pulmonary infection with minimal systemic dissemination is achieved with both smooth and rough morphotypes. In this model M. abscessus rough morphotype causes a greater host inflammatory response than the smooth based on bronchoalveolar lavage fluid neutrophil levels. PMID:25675351

  7. Physiological Integration Affects Expansion of an Amphibious Clonal Plant from Terrestrial to Cu-Polluted Aquatic Environments

    NASA Astrophysics Data System (ADS)

    Xu, Liang; Zhou, Zhen-Feng

    2017-03-01

    The effects of physiological integration on clonal plants growing in aquatic and terrestrial habitats have been extensively studied, but little is known about the role in the extension of amphibious clonal plants in the heterogeneous aquatic-terrestrial ecotones, especially when the water environments are polluted by heavy metals. Ramets of the amphibious clonal herb Alternanthera philoxeroides were rooted in unpolluted soil and polluted water at three concentrations of Cu. The extension of populations from unpolluted terrestrial to polluted aqueous environments mainly relied on stem elongation rather than production of new ramets. The absorbed Cu in the ramets growing in polluted water could be spread horizontally to other ramets in unpolluted soil via physiological integration and redistributed in different organs. The performances of ramets in both terrestrial and aquatic habitats were negatively correlated with Cu intensities in different organs of plants. It is concluded that physiological integration might lessen the fitness of connected ramets in heterogeneously polluted environments. The mechanical strength of the stems decreased with increasing Cu levels, especially in polluted water. We suggest that, except for direct toxicity to growth and expansion, heavy metal pollution might also increase the mechanical risk in breaking failure of plants.

  8. Physiological Integration Affects Expansion of an Amphibious Clonal Plant from Terrestrial to Cu-Polluted Aquatic Environments

    PubMed Central

    Xu, Liang; Zhou, Zhen-Feng

    2017-01-01

    The effects of physiological integration on clonal plants growing in aquatic and terrestrial habitats have been extensively studied, but little is known about the role in the extension of amphibious clonal plants in the heterogeneous aquatic-terrestrial ecotones, especially when the water environments are polluted by heavy metals. Ramets of the amphibious clonal herb Alternanthera philoxeroides were rooted in unpolluted soil and polluted water at three concentrations of Cu. The extension of populations from unpolluted terrestrial to polluted aqueous environments mainly relied on stem elongation rather than production of new ramets. The absorbed Cu in the ramets growing in polluted water could be spread horizontally to other ramets in unpolluted soil via physiological integration and redistributed in different organs. The performances of ramets in both terrestrial and aquatic habitats were negatively correlated with Cu intensities in different organs of plants. It is concluded that physiological integration might lessen the fitness of connected ramets in heterogeneously polluted environments. The mechanical strength of the stems decreased with increasing Cu levels, especially in polluted water. We suggest that, except for direct toxicity to growth and expansion, heavy metal pollution might also increase the mechanical risk in breaking failure of plants. PMID:28272515

  9. Physiological Integration Affects Expansion of an Amphibious Clonal Plant from Terrestrial to Cu-Polluted Aquatic Environments.

    PubMed

    Xu, Liang; Zhou, Zhen-Feng

    2017-03-08

    The effects of physiological integration on clonal plants growing in aquatic and terrestrial habitats have been extensively studied, but little is known about the role in the extension of amphibious clonal plants in the heterogeneous aquatic-terrestrial ecotones, especially when the water environments are polluted by heavy metals. Ramets of the amphibious clonal herb Alternanthera philoxeroides were rooted in unpolluted soil and polluted water at three concentrations of Cu. The extension of populations from unpolluted terrestrial to polluted aqueous environments mainly relied on stem elongation rather than production of new ramets. The absorbed Cu in the ramets growing in polluted water could be spread horizontally to other ramets in unpolluted soil via physiological integration and redistributed in different organs. The performances of ramets in both terrestrial and aquatic habitats were negatively correlated with Cu intensities in different organs of plants. It is concluded that physiological integration might lessen the fitness of connected ramets in heterogeneously polluted environments. The mechanical strength of the stems decreased with increasing Cu levels, especially in polluted water. We suggest that, except for direct toxicity to growth and expansion, heavy metal pollution might also increase the mechanical risk in breaking failure of plants.

  10. Impact of Temperature and Nutrients on Carbon: Nutrient Tissue Stoichiometry of Submerged Aquatic Plants: An Experiment and Meta-Analysis.

    PubMed

    Velthuis, Mandy; van Deelen, Emma; van Donk, Ellen; Zhang, Peiyu; Bakker, Elisabeth S

    2017-01-01

    Human activity is currently changing our environment rapidly, with predicted temperature increases of 1-5°C over the coming century and increased nitrogen and phosphorus inputs in aquatic ecosystems. In the shallow parts of these ecosystems, submerged aquatic plants enhance water clarity by resource competition with phytoplankton, provide habitat, and serve as a food source for other organisms. The carbon:nutrient stoichiometry of submerged aquatic plants can be affected by changes in both temperature and nutrient availability. We hypothesized that elevated temperature leads to higher carbon:nutrient ratios through enhanced nutrient-use efficiency, while nutrient addition leads to lower carbon:nutrient ratios by the luxurious uptake of nutrients. We addressed these hypotheses with an experimental and a meta-analytical approach. We performed a full-factorial microcosm experiment with the freshwater plant Elodea nuttallii grown at 10, 15, 20, and 25°C on sediment consisting of pond soil/sand mixtures with 100, 50, 25, and 12.5% pond soil. To address the effect of climatic warming and nutrient addition on the carbon:nutrient stoichiometry of submerged freshwater and marine plants we performed a meta-analysis on experimental studies that elevated temperature and/or added nutrients (nitrogen and phosphorus). In the microcosm experiment, C:N ratios of Elodea nuttallii decreased with increasing temperature, and this effect was most pronounced at intermediate nutrient availability. Furthermore, higher nutrient availability led to decreased aboveground C:P ratios. In the meta-analysis, nutrient addition led to a 25, 22, and 16% reduction in aboveground C:N and C:P ratios and belowground C:N ratios, accompanied with increased N content. No consistent effect of elevated temperature on plant stoichiometry could be observed, as very few studies were found on this topic and contrasting results were reported. We conclude that while nutrient addition consistently leads to

  11. Impact of Temperature and Nutrients on Carbon: Nutrient Tissue Stoichiometry of Submerged Aquatic Plants: An Experiment and Meta-Analysis

    PubMed Central

    Velthuis, Mandy; van Deelen, Emma; van Donk, Ellen; Zhang, Peiyu; Bakker, Elisabeth S.

    2017-01-01

    Human activity is currently changing our environment rapidly, with predicted temperature increases of 1–5°C over the coming century and increased nitrogen and phosphorus inputs in aquatic ecosystems. In the shallow parts of these ecosystems, submerged aquatic plants enhance water clarity by resource competition with phytoplankton, provide habitat, and serve as a food source for other organisms. The carbon:nutrient stoichiometry of submerged aquatic plants can be affected by changes in both temperature and nutrient availability. We hypothesized that elevated temperature leads to higher carbon:nutrient ratios through enhanced nutrient-use efficiency, while nutrient addition leads to lower carbon:nutrient ratios by the luxurious uptake of nutrients. We addressed these hypotheses with an experimental and a meta-analytical approach. We performed a full-factorial microcosm experiment with the freshwater plant Elodea nuttallii grown at 10, 15, 20, and 25°C on sediment consisting of pond soil/sand mixtures with 100, 50, 25, and 12.5% pond soil. To address the effect of climatic warming and nutrient addition on the carbon:nutrient stoichiometry of submerged freshwater and marine plants we performed a meta-analysis on experimental studies that elevated temperature and/or added nutrients (nitrogen and phosphorus). In the microcosm experiment, C:N ratios of Elodea nuttallii decreased with increasing temperature, and this effect was most pronounced at intermediate nutrient availability. Furthermore, higher nutrient availability led to decreased aboveground C:P ratios. In the meta-analysis, nutrient addition led to a 25, 22, and 16% reduction in aboveground C:N and C:P ratios and belowground C:N ratios, accompanied with increased N content. No consistent effect of elevated temperature on plant stoichiometry could be observed, as very few studies were found on this topic and contrasting results were reported. We conclude that while nutrient addition consistently leads to

  12. Compound-specific deltaD-delta13C analyses of n-alkanes extracted from terrestrial and aquatic plants.

    PubMed

    Chikaraishi, Yoshito; Naraoka, Hiroshi

    2003-06-01

    Stable hydrogen and carbon isotopic compositions of individual n-alkanes were determined for various terrestrial plants (33 samples including 27 species) and aquatic plants (six species) in natural environments from Japan and Thailand. In C3 plants, n-alkanes extracted from angiosperms have a deltaD value of -152+/-26 per thousand (relative to Standard Mean Ocean Water [SMOW]) and delta13C value of -36.1+/-2.7 per thousand (relative to Peedde Belemnite [PDB]), and those from gymnosperms have a deltaD value of -149+/-16 per thousand and delta13C value of -31.6+/-1.7 per thousand. Angiosperms have n-alkanes depleted in 13C relative to gymnosperms. n-Alkanes from C4 plants have a deltaD value of -171+/-12 per thousand and delta13C value of -20.5+/-2.1 per thousand, being a little depleted in D and much enriched in 13C compared to C3 plants. n-Alkanes of CAM plants are a little depleted in D and vary widely in delta13C relative to those of C3 and C4 plants. In aquatic plants, n-alkanes from freshwater plants have a deltaD value of -187+/-16 per thousand and delta13C value of -25.3+/-1.9 per thousand, and those from seaweeds have a deltaD value of -155+/-34 per thousand and delta13C value of -22.8+/-1.0 per thousand. All n-alkanes from various plant classes are more depleted in D and 13C relative to environmental water and bulk tissue, respectively. In addition, the hydrogen and carbon isotopic fractionations during n-alkane synthesis are distinctive for these various plant classes. While C3 plants have smaller isotopic fractionations in both D and 13C, seaweed has larger isotopic fractionations.

  13. Use of the aquatic plant Elodea canadensis to assess toxicity and genotoxicity of Yenisei River sediments.

    PubMed

    Zotina, Tatiana A; Trofimova, Elena A; Medvedeva, Marina Yu; Dementyev, Dmitry V; Bolsunovsky, Alexander Ya

    2015-10-01

    The toxicity, cytotoxicity, and genotoxicity of bulk sediments from the Yenisei River (Siberia, Russia) were estimated in laboratory bioassays based on several endpoints in the aquatic plant Elodea canadensis. The bottom sediment samples were collected in the Yenisei River upstream and downstream of the sources of chemical and radioactive contamination. The testing revealed different sensitivities of Elodea endpoints to the quality of the bottom sediment: weight of shoots < length of shoots < mitotic index < length of roots < percentage of abnormal cells. The response of the genotoxicity endpoint (percentage of cells with chromosome abnormalities in roots of Elodea) was the highest in sediments with chemical pollution, whereas the highest inhibition of toxicity endpoints (shoot and root length) occurred in sediments with the highest level of radioactive pollution. The extreme response of Elodea endpoints to the quality of certain sediment samples may be regarded as related to the possible presence of unknown toxicants. The results show that E. canadensis can be used as an indicator species in laboratory contact testing of bottom sediment. The responses of shoot and root length growth endpoints of Elodea can be recommended as basic sensitivity indicators of bottom sediment toxicity. Analysis of cells carrying abnormal chromosomes in the apical root meristem of Elodea can be performed optionally in the same test to assess the genotoxicity of sediments. © 2015 SETAC.

  14. Phytoremediation capacity of aquatic plants is associated with the degree of phytochelatin polymerization.

    PubMed

    Török, Anamaria; Gulyás, Zsolt; Szalai, Gabriella; Kocsy, Gábor; Majdik, Cornelia

    2015-12-15

    Phytochelatins (PCs) play important role in phytoremediation as heavy metal binding peptides. In the present study, the association between heavy metal removal capacity and phytochelatin synthesis was compared through the examination of three aquatic plants: Elodea canadensis, Salvinia natans and Lemna minor. In case of a Cd treatment, or a Cd treatment combined with Cu and Zn, the highest removal capacity was observed in L. minor. At the same time, E. canadensis showed the lowest removal capacity except for Zn. The heavy metal-induced (Cu+Zn+Cd) oxidative stress generated the highest ascorbate level in L. minor. Cd in itself or combined with the other two metals induced a 10-15-fold increase in the amount of ɣ-glutamylcysteine in L. minor while no or smaller changes were observed in the other two species. Correspondingly, the total PC content was 6-8-fold greater in L. minor. In addition, PCs with higher degree of polymerization were only observed in L. minor (PC4, PC6 and PC7) while PC2 and PC3 occurred in E. canadensis and S. natans only. The correlation analysis indicated that the higher phytoremediation capacity of L. minor was associated with the synthesis of PCs and their higher degree of polymerization.

  15. Application of microchip-CE electrophoresis to follow the degradation of phenolic acids by aquatic plants.

    PubMed

    Ding, Yongsheng; Garcia, Carlos D

    2006-12-01

    In this paper, we describe the separation and detection of six phenolic acids using an electrophoretic microchip with pulsed amperometric detection (PAD). The selected phenolic acids are particularly important because of their biological activity. The analysis of these compounds is typically performed by chromatography or standard CE coupled with a wide variety of detection modes. However, these methods are slow, labor intensive, involve a multistep solvent extraction, require skilled personnel, or use bulky and expensive instrumentation. In contrast, microchip CE offers the possibility of performing simpler, less expensive, and faster analysis. In addition, integrated devices can be custom-fabricated and incorporated with portable computers to perform on-site analysis. In the present report, the effect of the separation potential, buffer pH and composition, injection time and PAD parameters were studied in an effort to optimize both the separation and detection of these phenolic acids. Using the optimized conditions, the analysis can be performed in less than 3 min, with detection limits ranging from 0.73 microM (0.10 microg/mL) for 4-hydroxyphenylacetic acid to 2.12 microM (0.29 microg/mL) for salicylic acid. In order to demonstrate the capabilities of the device, the degradation of a mixture of these acids by two aquatic plants was followed using the optimized conditions.

  16. Modeling anaerobic digestion of aquatic plants by rumen cultures: cattail as an example.

    PubMed

    Zhao, Bai-Hang; Yue, Zheng-Bo; Ni, Bing-Jie; Mu, Yang; Yu, Han-Qing; Harada, Hideki

    2009-04-01

    Despite of the significance of the anaerobic digestion of lignocellulosic materials, only a limited number of studies have been carried out to evaluate the lignocellulosic digestion kinetics, and information about the modeling of this process is limited. In this work, a mathematical model, based on the Anaerobic Digestion Model No.1 (ADM1), was developed to describe the anaerobic conversion of lignocellulose-rich aquatic plants, with cattail as an example, by rumen microbes. Cattail was fractionated into slowly hydrolysable fraction (SHF), readily hydrolysable fraction (RHF) and inert fraction in the model. The SHF was hydrolyzed by rumen microbes and resulted in the production of RHF. The SHF and RHF had different hydrolysis rates but both with surface-limiting kinetics. The rumen microbial population diversity, including the cattail-, butyrate-, acetate- and H(2)-degraders, was all incorporated in the model structure. Experiments were carried out to identify the parameters and to calibrate and validate this model. The simulation results match the experimental data, implying that the fractionation of cattail into two biodegradation parts, i.e., SHF and RHF, and modeling their hydrolysis rate with a surface-limiting kinetics were appropriate. The model was capable of simulating the anaerobic biodegradation of cattail by the rumen cultures.

  17. Numerical modelling of distribution the discharged heat water from thermal power plant on the aquatic environment

    NASA Astrophysics Data System (ADS)

    Issakhov, Alibek

    2016-06-01

    The paper presents a mathematical model of distribution the discharged heat water from thermal power plant under various operational capacities on the aquatic environment. It was solved by the Navier-Stokes and temperature equations for an incompressible fluid in a stratified medium were based on the splitting method by physical parameters which approximated by the finite volume method. The numerical solution of the equation system was divided into four stages. At the first step it was assumed that the momentum transfer carried out only by convection and diffusion. While the intermediate velocity field was solved by 5-step Runge-Kutta method. At the second stage, the pressure field was solved by found the intermediate velocity field. Whereas Poisson equation for the pressure field was solved by Jacobi method. The third step assumes that the transfer was carried out only by pressure gradient. Finally the fourth step of the temperature equation was also solved as motion equations, with 5-step Runge-Kutta method. The algorithm was parallelized on high-performance computer. The obtained numerical results of three-dimensional stratified turbulent flow were compared with experimental data. What revealed qualitatively and quantitatively approximately the basic laws of hydrothermal processes occurring in the reservoir-cooler.

  18. CO2-concentrating mechanisms in Egeria densa, a submersed aquatic plant.

    PubMed

    Lara, María V; Casati, Paula; Andreo, Carlos S

    2002-08-01

    Egeria densa is an aquatic higher plant which has developed different mechanisms to deal with photosynthesis under conditions of low CO2 availability. On the one hand it shows leaf pH-polarity, which has been proposed to be used for bicarbonate utilization. In this way, at high light intensities and low dissolved carbon concentration, this species generates a low pH at the adaxial leaf surface. This acidification shifts the equilibrium HCO3-/CO2 towards CO2, which enters the cell by passive diffusion. By this means, E. densa increases the concentration of CO2 available for photosynthesis inside the cells, when this gas is limiting. On the other hand, under stress conditions resulting from high temperature and high light intensities, it shows a biochemical adaptation with the induction of a C4-like mechanism but without Kranz anatomy. Transfer from low to high temperature and light conditions induces increased levels of phosphoenolpyruvate carboxylase (PEPC, EC 4.1.1.31) and NADP-malic enzyme (NADP-ME, EC 1.1.1.40), both key enzymes participating in the Hatch-Slack cycle in plants with C4 metabolism. Moreover, one PEPC isoform, whose synthesis is induced by high temperature and light, is phosphorylated in the light, and changes in kinetic and regulatory properties are correlated with changes in the phosphorylation state of this enzyme. In the present review, we describe these two processes in this submersed angiosperm that appear to help it perform photosynthesis under conditions of extreme temperatures and high light intensities.

  19. Effects of riparian plant diversity loss on aquatic microbial decomposers become more pronounced with increasing time.

    PubMed

    Fernandes, Isabel; Duarte, Sofia; Cássio, Fernanda; Pascoal, Cláudia

    2013-11-01

    We examined the potential long-term impacts of riparian plant diversity loss on diversity and activity of aquatic microbial decomposers. Microbial assemblages were obtained in a mixed-forest stream by immersion of mesh bags containing three leaf species (alder, oak and eucalyptus), commonly found in riparian corridors of Iberian streams. Simulation of species loss was done in microcosms by including a set of all leaf species, retrieved from the stream, and non-colonized leaves of three, two or one leaf species. Leaves were renewed every month throughout six months, and microbial inoculum was ensured by a set of colonized leaves from the previous month. Microbial diversity, leaf mass loss and fungal biomass were assessed at the second and sixth months after plant species loss. Molecular diversity of fungi and bacteria, as the total number of operational taxonomic units per leaf diversity treatment, decreased with leaf diversity loss. Fungal biomass tended to decrease linearly with leaf species loss on oak and eucalyptus, suggesting more pronounced effects of leaf diversity on lower quality leaves. Decomposition of alder and eucalyptus leaves was affected by leaf species identity, mainly after longer times following diversity loss. Leaf decomposition of alder decreased when mixed with eucalyptus, while decomposition of eucalyptus decreased in mixtures with oak. Results suggest that the effects of leaf diversity on microbial decomposers depended on leaf species number and also on which species were lost from the system, especially after longer times. This may have implications for the management of riparian forests to maintain stream ecosystem functioning.

  20. Algal and aquatic plant carbon concentrating mechanisms in relation to environmental change.

    PubMed

    Raven, John A; Giordano, Mario; Beardall, John; Maberly, Stephen C

    2011-09-01

    species with or without CCMs. The information available permits less predictive power as to the effect of the forcing factors on CCM expression than for their overall effects on growth. CCMs are currently not part of models as to how global environmental change has altered, and is likely to further alter, algal and aquatic plant primary productivity.

  1. Why are most aquatic plants widely distributed? Dispersal, clonal growth and small-scale heterogeneity in a stressful environment

    NASA Astrophysics Data System (ADS)

    Santamaría, Luis

    2002-06-01

    Non-marine aquatic vascular plants generally show broad distributional ranges. Climatic factors seem to have limited effects on their distributions, besides the determination of major disjunctions (tropical-temperate-subarctic). Dispersal should have been frequent enough to assure the quick colonisation of extensive areas following glacial retreat, but dispersal limitation is still apparent in areas separated by geographic barriers. Aquatic vascular plants also show limited taxonomic differentiation and low within-species genetic variation. Variation within populations is particularly low, but variation among populations seems to be relatively high, mainly due to the persistence of long-lived clones. Ecotypic differentiation is often related to factors that constrain clonal reproduction (salinity and ephemeral inundation). Inland aquatic habitats are heterogeneous environments, but this heterogeneity largely occurs at relatively small scales (within waterbodies and among neighbouring ones). They also represent a stressful environment for plants, characterised by low carbon availability, shaded conditions, sediment anoxia, mechanical damage by currents and waves, significant restrictions to sexual reproduction, and sometimes also osmotic stress and limited nutrient supply. I propose that the generality of broad distributions and low differentiation among the inland aquatic flora is best explained by a combination of: (1) selection for stress-tolerant taxa with broad tolerance ranges. (2) The selective advantages provided by clonal growth and multiplication, which increases plant tolerance to stress, genet survivorship and population viability. (3) Long-distance dispersal of sexual propagules and high local dispersal of asexual clones. (4) The generality of broad plastic responses, promoted by the combination of clonal growth, high local dispersal, small-scale spatial heterogeneity and temporal variability.

  2. Aquatic Plant Control Research Program: 2,4-D Concentration and Exposure Time Relationships for the Control of Eurasian Watermilfoil

    DTIC Science & Technology

    1988-11-01

    residue concentration collected within this treated plot was 1.3 mg ae/Z. The other two applications which provided only Eurasian water- milfoil injury (C...Eurasian watermilfoil injury but not complete control. The Eurasian water- milfoil treated in this field test (Getsinger and Westerdahl 1984) exhibited...34The Response of Eurasian Water- milfoil to Various Concentrations and Exposure Periods of 2,4-D," Journal of Aquatic Plant Control, Vol 10, pp 38-40

  3. Aquatic Plant Control Research Program. Effects of Endothall Treatment on Phosphorus Concentration and Community Metabolism of Aquatic Communities.

    DTIC Science & Technology

    1984-02-01

    13.551 73 APPENDIX 8 ) issolved Oxygen and l’emp erature Chaanes for Ca lculat ion ot Microcosm Metabolism, 0 (°C) Akpri1 19 rime IC 2E 3C 4E C 6E 8:30...were, iorifii ted to exriminIe changes in phosphorus , oxygen , II iftIh LhIrphyl I a I orceritrat Iorns al ter thre appl icat ion oif the herbicide...plant decomposition. Nichols and Keeney (1973) realized the importance of the sediment and the effect of oxygenation on the fate of tissue phosphorus in

  4. Estimating site occupancy rates for aquatic plants using spatial sub-sampling designs when detection probabilities are less than one

    USGS Publications Warehouse

    Nielson, Ryan M.; Gray, Brian R.; McDonald, Lyman L.; Heglund, Patricia J.

    2011-01-01

    Estimation of site occupancy rates when detection probabilities are <1 is well established in wildlife science. Data from multiple visits to a sample of sites are used to estimate detection probabilities and the proportion of sites occupied by focal species. In this article we describe how site occupancy methods can be applied to estimate occupancy rates of plants and other sessile organisms. We illustrate this approach and the pitfalls of ignoring incomplete detection using spatial data for 2 aquatic vascular plants collected under the Upper Mississippi River's Long Term Resource Monitoring Program (LTRMP). Site occupancy models considered include: a naïve model that ignores incomplete detection, a simple site occupancy model assuming a constant occupancy rate and a constant probability of detection across sites, several models that allow site occupancy rates and probabilities of detection to vary with habitat characteristics, and mixture models that allow for unexplained variation in detection probabilities. We used information theoretic methods to rank competing models and bootstrapping to evaluate the goodness-of-fit of the final models. Results of our analysis confirm that ignoring incomplete detection can result in biased estimates of occupancy rates. Estimates of site occupancy rates for 2 aquatic plant species were 19–36% higher compared to naive estimates that ignored probabilities of detection <1. Simulations indicate that final models have little bias when 50 or more sites are sampled, and little gains in precision could be expected for sample sizes >300. We recommend applying site occupancy methods for monitoring presence of aquatic species.

  5. The role of roots in the accumulation and removal of cadmium by the aquatic plant Hydrilla verticillata.

    PubMed

    He, Yan; Rui, Haiyun; Chen, Chen; Chen, Yahua; Shen, Zhenguo

    2016-07-01

    Aquatic macrophytes can absorb heavy metals either from sediments via the root system, from the water phase by leaves, or from both sources. In this study, cadmium accumulation and distribution in the aquatic plant Hydrilla verticillata were investigated, with a focus on the role of roots. Results showed that leaves of H. verticillata had a higher Cd concentration than roots when intact plants were grown in sediments and solutions containing Cd. Cadmium can significantly decrease the leaf chlorophyll content, and the leaves of intact plants with roots had lower chlorophyll contents than the leaves of detached ones without roots due to the transfer effect of roots. The majority of the Cd accumulated in leaves of H. verticillata was bound to the cell walls. When roots were submerged in a solution containing Cd, with shoots in a control solution without Cd, the Cd concentrations in leaves were considerably lower than in roots. In contrast, Cd was almost undetectable in roots when the shoots were submerged in a solution containing Cd, with roots in the control solution. Compared to the leaves and stems of detached shoots without roots, the concentrations of Cd were much higher in the leaves and stems of intact plants with roots. It is suggested that the roots of intact plants absorb Cd and transfer it to leaves and that more Cd is removed from the solution by intact plants.

  6. Roles for root iron plaque in sequestration and uptake of heavy metals and metalloids in aquatic and wetland plants.

    PubMed

    Tripathi, Rudra D; Tripathi, Preeti; Dwivedi, Sanjay; Kumar, Amit; Mishra, Aradhana; Chauhan, Puneet S; Norton, Gareth J; Nautiyal, Chandra S

    2014-10-01

    Toxic metal(loid) contamination of soil and sediment poses long term risk to soil and human health through plant-human or plant-animal-human food chain pathways. Iron plaque (IP) formation is frequent in aquatic and wetland plant species and is responsible for the sequestration of various metal(loids). The presence of IP may act as a buffer or barrier and may thus enhance or reduce the uptake of potentially phytotoxic metals and metalloids by plants. If IP acts as a barrier, then low IP producing macrophytes/aquatic plants may be better accumulators of toxic metals and may find use in constructed wetlands for remediation of pollutants, while high IP forming edible plant species could be safer for human consumption. Conversely, if IP acts as a buffer for mineral nutrients and toxic elements then those cultivars may be rich in nutrients, but may also cause toxicity. However, an ecotoxicological risk is also inevitable if IP rich macrophyte roots containing heavy metals are consumed by herbivores. In this review, we summarize the current understanding about the role of IP in metal and metalloid sequestration, uptake, and transport. Furthermore, we will address the role of root IP in Oryza sativa for arsenic (As) sequestration leading to lower grain As translocation, reducing the risk of human exposure.

  7. Cytokinin, auxin and physiological polarity in the aquatic carnivorous plants Aldrovanda vesiculosa and Utricularia australis.

    PubMed

    Šimura, Jan; Spíchal, Lukáš; Adamec, Lubomír; Pěnčík, Aleš; Rolčík, Jakub; Novák, Ondřej; Strnad, Miroslav

    2016-05-01

    The typical rootless linear shoots of aquatic carnivorous plants exhibit clear, steep polarity associated with very rapid apical shoot growth. The aim of this study was to determine how auxin and cytokinin contents are related to polarity and shoot growth in such plants. The main auxin and cytokinin metabolites in separated shoot segments and turions of two carnivorous plants, Aldrovanda vesiculosa and Utricularia australis, were analysed using ultra-high-performance liquid chromatography coupled with triple quad mass spectrometry. In both species, only isoprenoid cytokinins were identified. Zeatin cytokinins predominated in the apical parts, with their concentrations decreasing basipetally, and the trans isomer predominated in A. vesiculosa whereas the cis form was more abundant in U australis. Isopentenyladenine-type cytokinins, in contrast, increased basipetally. Conjugated cytokinin metabolites, the O-glucosides, were present at high concentrations in A. vesiculosa but only in minute amounts in U. australis. N(9)-glucoside forms were detected only in U. australis, with isopentenyladenine-9-glucoside (iP9G) being most abundant. In addition to free indole-3-acetic acid (IAA), indole-3-acetamide (IAM), IAA-aspartate (IAAsp), IAA-glutamate (IAGlu) and IAA-glycine (IAGly) conjugates were identified. Both species show common trends in auxin and cytokinin levels, the apical localization of the cytokinin biosynthesis and basipetal change in the ratio of active cytokinins to auxin, in favour of auxin. However, our detailed study of cytokinin metabolic profiles also revealed that both species developed different regulatory mechanisms of active cytokinin content; on the level of their degradation, in U. australis, or in the biosynthesis itself, in the case of A. vesiculosa Results indicate that the rapid turnover of these signalling molecules along the shoots is essential for maintaining the dynamic balance between the rapid polar growth and development of the apical

  8. Ecotoxicity and environmental risk assessment of pharmaceuticals and personal care products in aquatic environments and wastewater treatment plants.

    PubMed

    Ortiz de García, Sheyla Andrea; Pinto Pinto, Gilberto; García-Encina, Pedro A; Irusta-Mata, Rubén

    2014-10-01

    A wide range of pharmaceuticals and personal care products (PPCPs) are present in the environment, and many of their adverse effects are unknown. The environmental risk assessment of 26 PPCPs of relevant consumption and occurrence in the aquatic environment in Spain was accomplished in this research. Based on the ecotoxicity values obtained by bioluminescence and respirometry assays and by predictions using the US EPA ecological structure-activity relationship (ECOSAR™), the compounds were classified following the Globally Harmonized System of Classification and Labelling of Chemicals. According to the criteria of the European Medicines Agency, the real risk of impact of these compounds in wastewater treatment plants (WWTPs) and in the aquatic environment was predicted. In at least two ecotoxicity tests, 65.4 % of the PPCPs under study showed high toxicity or were harmful to aquatic organisms. The global order of the species' sensitivity to the PPCPs considered was as follows: Vibrio fischeri (5 min) > Vibrio fischeri (15 min) > algae > crustaceans > fish > biomass of WWTP. Acetaminophen, ciprofloxacin, clarithromycin, clofibrate, ibuprofen, omeprazole, triclosan, parabens and 1,4-benzoquinone showed some type of risk for the aquatic environments and/or for the activated sludge of WWTPs. Development of acute and chronic ecotoxicity data, the determination of predicted and measured environmental concentrations of PPCPs, the inclusion of metabolites and transformation products and the evaluation of mixtures of these compounds will allow further improvements of the results of the ERAs and, finally, to efficiently identify the compounds that could affect the environment.

  9. Genome Size as a Key to Evolutionary Complex Aquatic Plants: Polyploidy and Hybridization in Callitriche (Plantaginaceae)

    PubMed Central

    Prančl, Jan; Kaplan, Zdeněk; Trávníček, Pavel; Jarolímová, Vlasta

    2014-01-01

    Despite their complex evolutionary histories, aquatic plants are highly underrepresented in contemporary biosystematic studies. Of them, the genus Callitriche is particularly interesting because of such evolutionary features as wide variation in chromosome numbers and pollination systems. However, taxonomic difficulties have prevented broader investigation of this genus. In this study we applied flow cytometry to Callitriche for the first time in order to gain an insight into evolutionary processes and genome size differentiation in the genus. Flow cytometry complemented by confirmation of chromosome counts was applied to an extensive dataset of 1077 Callitriche individuals from 495 localities in 11 European countries and the USA. Genome size was determined for 12 taxa. The results suggest that many important processes have interacted in the evolution of the genus, including polyploidization and hybridization. Incongruence between genome size and ploidy level, intraspecific variation in genome size, formation of autotriploid and hybridization between species with different pollination systems were also detected. Hybridization takes place particularly in the diploid – tetraploid complex C. cophocarpa – C. platycarpa, for which the triploid hybrids were frequently recorded in the area of co-occurrence of its parents. A hitherto unknown hybrid (probably C. hamulata × C. cophocarpa) with a unique chromosome number was discovered in the Czech Republic. However, hybridization occurs very rarely among most of the studied species. The main ecological preferences were also compared among the taxa collected. Although Callitriche taxa often grow in mixed populations, the ecological preferences of individual species are distinctly different in some cases. Anyway, flow cytometry is a very efficient method for taxonomic delimitation, determination and investigation of Callitriche species, and is even able to distinguish homoploid taxa and identify introduced species. PMID

  10. Performance of aquatic plant species for phytoremediation of arsenic-contaminated water

    NASA Astrophysics Data System (ADS)

    Jasrotia, Shivakshi; Kansal, Arun; Mehra, Aradhana

    2017-05-01

    This study investigates the effectiveness of aquatic macrophyte and microphyte for phytoremediation of water bodies contaminated with high arsenic concentration. Water hyacinth ( Eichhornia crassipes) and two algae ( Chlorodesmis sp. and Cladophora sp.) found near arsenic-enriched water bodies were used to determine their tolerance toward arsenic and their effectiveness to uptake arsenic thereby reducing organic pollution in arsenic-enriched wastewater of different concentrations. Parameters like pH, chemical oxygen demand (COD), and arsenic concentration were monitored. The pH of wastewater during the course of phytoremediation remained constant in the range of 7.3-8.4, whereas COD reduced by 50-65 % in a period of 15 days. Cladophora sp. was found to survive up to an arsenic concentration of 6 mg/L, whereas water hyacinth and Chlorodesmis sp. could survive up to arsenic concentrations of 2 and 4 mg/L, respectively. It was also found that during a retention period of 10 days under ambient temperature conditions, Cladophora sp. could bring down arsenic concentration from 6 to <0.1 mg/L, Chlorodesmis sp. was able to reduce arsenic by 40-50 %; whereas, water hyacinth could reduce arsenic by only 20 %. Cladophora sp. is thus suitable for co-treatment of sewage and arsenic-enriched brine in an algal pond having a retention time of 10 days. The identified plant species provides a simple and cost-effective method for application in rural areas affected with arsenic problem. The treated water can be used for irrigation.

  11. Performance of aquatic plant species for phytoremediation of arsenic-contaminated water

    NASA Astrophysics Data System (ADS)

    Jasrotia, Shivakshi; Kansal, Arun; Mehra, Aradhana

    2015-06-01

    This study investigates the effectiveness of aquatic macrophyte and microphyte for phytoremediation of water bodies contaminated with high arsenic concentration. Water hyacinth (Eichhornia crassipes) and two algae (Chlorodesmis sp. and Cladophora sp.) found near arsenic-enriched water bodies were used to determine their tolerance toward arsenic and their effectiveness to uptake arsenic thereby reducing organic pollution in arsenic-enriched wastewater of different concentrations. Parameters like pH, chemical oxygen demand (COD), and arsenic concentration were monitored. The pH of wastewater during the course of phytoremediation remained constant in the range of 7.3-8.4, whereas COD reduced by 50-65 % in a period of 15 days. Cladophora sp. was found to survive up to an arsenic concentration of 6 mg/L, whereas water hyacinth and Chlorodesmis sp. could survive up to arsenic concentrations of 2 and 4 mg/L, respectively. It was also found that during a retention period of 10 days under ambient temperature conditions, Cladophora sp. could bring down arsenic concentration from 6 to <0.1 mg/L, Chlorodesmis sp. was able to reduce arsenic by 40-50 %; whereas, water hyacinth could reduce arsenic by only 20 %. Cladophora sp. is thus suitable for co-treatment of sewage and arsenic-enriched brine in an algal pond having a retention time of 10 days. The identified plant species provides a simple and cost-effective method for application in rural areas affected with arsenic problem. The treated water can be used for irrigation.

  12. Effectiveness of emergent and submergent aquatic plants in mitigating a nitrogen-permethrin mixture

    USDA-ARS?s Scientific Manuscript database

    The current study assessed the effectiveness of varying combinations of two common aquatic vascular macrophytes, parrot feather (Myriophyllum aquaticum) and cattail (Typha latifolia) for mitigating contamination from a mixture of nitrogen (ammonium nitrate) and permethrin. Hydraulically connected we...

  13. Aquatic plants: Ecology and environment. (Latest citations from the Selected Water Resources Abstracts database). Published Search

    SciTech Connect

    Not Available

    1993-09-01

    The bibliography contains citations concerning growth and ecology of aquatic flora in lakes, rivers, and coastal areas. Effects of domestic sewage, industrial wastes, and oil spills on aquatic ecosystems are discussed. Algal population growth in rivers and polluted areas is considered, and use of benthic algae as biological indicators of water quality is also discussed. (Contains a minimum of 90 citations and includes a subject term index and title list.)

  14. Aquatic macroinvertebrates collected at Ravenna Army Ammunition Plant, Portage and Trumbull Counties, Ohio, 1998

    USGS Publications Warehouse

    Tertuliani, John S.

    1999-01-01

    The results of a survey of macroinvertebrate communities in the Ravenna Army Ammunition Plant, were used as an indicator of disturbance in streams flowing through or near the training areas at the Plant. The data were interpreted using the Invertebrate Community Index (ICI), a multiple-metric index developed by the Ohio Environmental Protection Agency and based on the structural and functional characteristics of the macroinvertebrate community. Quantitative samples of the macroinvertebrate were collected for ICI determination from three streams South Fork Eagle Creek, Sand Creek, and Hinkley Creek flowing through the study area. These samples were collected using Hester-Dendy type artificial substrate samplers, which were placed in the streams during a 6-week sampling period, June 2 through July 15, 1998. A qualitative- dipnet sample from the natural substrates also was collected at each station on July 15, 1998, the last day of the sampling period. The macroinvertebrate communities at all three stations met the criterion designated for warmwater habitat aquatic life use, and communities at two of the three stations exceeded the criterion. The ICI scores were 42 at South Fork Eagle Creek, 50 at Sand Creek, and 48 at Hinkley Creek. The density of macroinvertebrates at South Fork Eagle Creek was 1,245 per square foot and represented 38 distinct taxa. The density at Sand Creek was 246 per square foot and represented 29 distinct taxa. The density at Hinkley Creek was 864 per square foot and represented 36 distinct taxa. Qualitative samples were also collected at 21 other sites using a D-framed dipnet. The qualitative sites encompassed three main environments: stream, pond, and swamp-wetland. All available habitat types in each environment were sampled until no new taxa were evident during coarse examination. The highest number of taxa were collected from the streams. The total number of taxa collected in streams ranged from 25 to 76; the mean was 60 and median 64. The

  15. Comparison of the Photosynthetic Characteristics of Three Submersed Aquatic Plants 1

    PubMed Central

    Van, Thai K.; Haller, William T.; Bowes, George

    1976-01-01

    Light- and CO2-saturated photosynthetic rates of the submersed aquatic plants Hydrilla verticillata, Ceratophyllum demersum, and Myriophyllum spicatum were 50 to 60 μmol O2/mg Chl·hr at 30 C. At air levels of CO2, the rates were less than 5% of those achieved by terrestrial C3 plants. The low photosynthetic rates correlated with low activities of the carboxylation enzymes. In each species, ribulose 1,5-diphosphate carboxylase was the predominant carboxylation enzyme. The apparent Km(CO2) values for photosynthesis were 150 to 170 μm at pH 4, and 75 to 95 μm at pH 8. The Km(CO2) of Hydrilla ribulose 1,5-diphosphate carboxylase was 45 μm at pH 8. Optimum temperatures for the photosynthesis of Hydrilla, Myriophyllum, and Ceratophyllum were 36.5, 35.0, and 28.5 C, respectively. The apparent ability of each species to use HCO3− ions for photosynthesis was similar, but at saturating free CO2 levels, there was no indication of HCO3− use. Increasing the pH from 3.1 to 9.2 affected the photosynthetic rate indirectly, by decreasing the free CO2. With saturating free CO2 (0.5 mm), the maximum photosynthetic rates were similar at pH 4 and 8. Carbonic anhydrase activity, although much lower than in terrestrial C3 plants, was still in excess of that required to support HCO3− utilization. Hydrilla and Ceratophyllum had CO2 compensation points of 44 and 41 μl/l, respectively, whereas the value for Myriophyllum was 19. Relatively high CO2 compensation points under 1% O2 indicated that some “dark” respiration occurred in the light. The inhibition of photosynthesis by O2 was less than with terrestrial C3 plants. Glycolate oxidase activity was 12.3 to 27.5 μmol O2/mg Chl·hr, as compared to 78.4 for spinach. Light saturation of photosynthesis occurred at 600 to 700 μeinsteins/m2·sec in each species grown under full sunlight. Hydrilla had the lowest light compensation point, and required the least irradiance to achieve the half-maximal photosynthetic rate. Field

  16. Accumulation of arsenic by aquatic plants in large-scale field conditions: opportunities for phytoremediation and bioindication.

    PubMed

    Favas, Paulo J C; Pratas, João; Prasad, M N V

    2012-09-01

    This work focuses on the potential of aquatic plants for bioindication and/or phytofiltration of arsenic from contaminated water. More than 71 species of aquatic plants were collected at 200 sampling points in running waters. The results for the 18 most representative plant species are presented here. The species Ranunculus trichophyllus, Ranunculus peltatus subsp. saniculifolius, Lemna minor, Azolla caroliniana and the leaves of Juncus effusus showed a very highly significant (P<0.001) positive correlation with the presence of arsenic in the water. These species may serve as arsenic indicators. The highest concentration of arsenic was found in Callitriche lusitanica (2346 mg/kg DW), Callitriche brutia (523 mg/kg DW), L. minor (430 mg/kg DW), A. caroliniana (397 mg/kg DW), R. trichophyllus (354 mg/kg DW), Callitriche stagnalis (354 mg/kg DW) and Fontinalis antipyretica (346 mg/kg DW). These results indicate the potential application of these species for phytofiltration of arsenic through constructed treatment wetlands or introduction of these plant species into natural water bodies.

  17. [PAHs concentrations in aquatic products and food safety evaluation in the coupled mangrove planting-aquaculture ecological system].

    PubMed

    Chen, Guan-Qiu; Li, Yao-Chu; Huang, Jin-Mu; Nan, Yan; Lin, Mao-Hong

    2012-06-01

    In order to know about the PAHs concentration in aquatic products from mangrove planting-aquaculture ecological system and to make sure of food quality and food safety, HPLC was used to determine concentrations of 13 polycyclic aromatic hydrocarbons (PAHs) in the Tilapia mossambica, Mugil cephalu and Concha ostreae from coupled mangrove planting-aquaculture ponds, food safety in aquatic products was also evaluated. The 13 PAHs were Fluorene (Flu), Phenanthrene (Phe), Anthracene (Ant), Fluoranthene (Fla), Pyrene (Pyr), Benz[a] anthraces (BaA), Chrysene (Chr), Benzo[b] fluoranthene (BbF), Benzo[k] fluoranthene (BkF), Benzo[a] Pyrene (BaP), Dibenzo [a, h] anthercene (DahA), Benzo [g, h, i] perylene (BghiP) and Indeno [1,2,3-c, d] pyrene (InP). Concentrations of PAHs were the highest in Concha ostreae which were in the range of 89.79-98.49 microg x kg(-1) dry weight, while those were in the range of 25.97-34.64 microg x kg(-1) in Mugil cephalu and 12.31-14.41 microg x kg(-1) in Tilapia mossambica. The content of fat affected the levels of PAHs content in different aquatic products. The individual composition of PAHs was characterized by 3 rings in samples with the range of 41.58% - 83.35%. Comparing with other areas, PAHs pollution of aquatic products in the studied area was in the mild level. Values of the total BaP(eq) concentration ranged from 0.0689 microg x kg(-1) to 1.0373 microg x kg(-1), which were lower than the maximum level set by European Union.

  18. Aquatic Plant Control Research Program. Large-Scale Operations Management Test of Use of the White Amur for Control of Problem Aquatic Plants. Reports 2 and 3. First and Second Year Poststocking Results. Volume 5. The Herpetofauna of Lake Conway, Florida: Community Analysis.

    DTIC Science & Technology

    1983-07-01

    AD Al 34 34 1 AQUATIC PLANT CONTROL RESEARCH PROGRAM LARGE-SC ALE Ij OPERATIONS MANAG E MENT . Ul UNIVERSITY OF SOUTH FLORIDA TAMPA DEPT OF BIOLOGY R...TEST CHART NATIONAL BVIREAU OF StANARS-1963- I AQUATIC PLANT CONTROL RESEARCH PROGRAM TECHNICAL REPORT A-78-2 LARGE-SCALE OPERATIONS MANAGEMENT TEST OF...Road, Springfield, Va. 22161. 19. KEY BORDS (Continue.o --- ,.. old. it ,o..0,y And IdentiIy by block -ob) Amphibia Reptiles Aquatic plant control

  19. Hydraulic Consequences of Hydrilla, an Invasive Submerged Aquatic Plant, in Freshwater Tidal Channels

    NASA Astrophysics Data System (ADS)

    Jenner, B. A.; Prestegaard, K. L.

    2010-12-01

    Hydrilla is a non-indigenous submerged aquatic plant that has become common in the southeast and mid-Atlantic regions of the United States. The purpose of this research is to evaluate the effects of Hydrilla on flow resistance, velocity, and discharge in freshwater tidal channels along the Patuxent River, MD. Hydrilla height is limited by the level of average low tide in tidal channels; therefore, it has preferentially invaded larger, deeper channels. Geomorphic and hydraulic measurements were made at 6 sites in the channel network of a large, freshwater tidal marsh in the spring, prior to Hydrilla regrowth, and in late summer when vegetation height was at a maximum. Field measurements of vegetation height (Zo), gauge height, energy gradient, velocity profiles, and maximum velocity were used to calculate mean channel velocity, shear velocity, and flow resistance (u/u* and Manning’s n) for the two vegetative conditions. “At-a-station” and “Downstream” hydraulic geometry relationships (the power function relationships of discharge to width, depth, and velocity) were also determined for maximum and minimum vegetation conditions. Results indicate that flow resistance increased and velocity decreased by an order of magnitude between Hydrilla minima and maxima heights. Tidal marsh channels typically exhibit rapid decreases in channel width and cross sectional area in the up-marsh direction. These decreases in width serve to maintain channel velocities and bring sediment, organic matter, and other materials into tidal marshes. Therefore, the downstream hydraulic geometry exponents for width are large and exponents are near zero for velocity, in most measured tidal marsh systems. Our measurements indicate that mean channel velocity decreases significantly in the up-marsh direction during maximum vegetation. This generates an exponent for velocity in the downstream hydraulic geometry relationships that is significantly larger than observed in other tidal systems

  20. Can sacrificial feeding areas protect aquatic plants from herbivore grazing? Using behavioural ecology to inform wildlife management.

    PubMed

    Wood, Kevin A; Stillman, Richard A; Daunt, Francis; O'Hare, Matthew T

    2014-01-01

    Effective wildlife management is needed for conservation, economic and human well-being objectives. However, traditional population control methods are frequently ineffective, unpopular with stakeholders, may affect non-target species, and can be both expensive and impractical to implement. New methods which address these issues and offer effective wildlife management are required. We used an individual-based model to predict the efficacy of a sacrificial feeding area in preventing grazing damage by mute swans (Cygnus olor) to adjacent river vegetation of high conservation and economic value. The accuracy of model predictions was assessed by a comparison with observed field data, whilst prediction robustness was evaluated using a sensitivity analysis. We used repeated simulations to evaluate how the efficacy of the sacrificial feeding area was regulated by (i) food quantity, (ii) food quality, and (iii) the functional response of the forager. Our model gave accurate predictions of aquatic plant biomass, carrying capacity, swan mortality, swan foraging effort, and river use. Our model predicted that increased sacrificial feeding area food quantity and quality would prevent the depletion of aquatic plant biomass by swans. When the functional response for vegetation in the sacrificial feeding area was increased, the food quantity and quality in the sacrificial feeding area required to protect adjacent aquatic plants were reduced. Our study demonstrates how the insights of behavioural ecology can be used to inform wildlife management. The principles that underpin our model predictions are likely to be valid across a range of different resource-consumer interactions, emphasising the generality of our approach to the evaluation of strategies for resolving wildlife management problems.

  1. Can Sacrificial Feeding Areas Protect Aquatic Plants from Herbivore Grazing? Using Behavioural Ecology to Inform Wildlife Management

    PubMed Central

    Wood, Kevin A.; Stillman, Richard A.; Daunt, Francis; O’Hare, Matthew T.

    2014-01-01

    Effective wildlife management is needed for conservation, economic and human well-being objectives. However, traditional population control methods are frequently ineffective, unpopular with stakeholders, may affect non-target species, and can be both expensive and impractical to implement. New methods which address these issues and offer effective wildlife management are required. We used an individual-based model to predict the efficacy of a sacrificial feeding area in preventing grazing damage by mute swans (Cygnus olor) to adjacent river vegetation of high conservation and economic value. The accuracy of model predictions was assessed by a comparison with observed field data, whilst prediction robustness was evaluated using a sensitivity analysis. We used repeated simulations to evaluate how the efficacy of the sacrificial feeding area was regulated by (i) food quantity, (ii) food quality, and (iii) the functional response of the forager. Our model gave accurate predictions of aquatic plant biomass, carrying capacity, swan mortality, swan foraging effort, and river use. Our model predicted that increased sacrificial feeding area food quantity and quality would prevent the depletion of aquatic plant biomass by swans. When the functional response for vegetation in the sacrificial feeding area was increased, the food quantity and quality in the sacrificial feeding area required to protect adjacent aquatic plants were reduced. Our study demonstrates how the insights of behavioural ecology can be used to inform wildlife management. The principles that underpin our model predictions are likely to be valid across a range of different resource-consumer interactions, emphasising the generality of our approach to the evaluation of strategies for resolving wildlife management problems. PMID:25077615

  2. 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.

  3. Final environmental assessment: Demonstration of use of grass carp in management of aquatic plants in Guntersville Reservoir

    SciTech Connect

    Not Available

    1990-03-01

    The Tennessee Valley Authority (TVA) plans to introduce triploid (sterile) grass carp into Guntersville Reservoir to test their usefulness in managing aquatic vegetation in a reservoir system. This demonstration is compatible with the long-range management plan for Guntersville Reservoir being developed jointly by TVA and the US Army Corps of Engineers at the request of several members of Congress. TVA is not at this time proposing to include grass carp as a routine component if its ongoing aquatic plant management program for Guntersville Reservoir or the TVA reservoir system. TVA's present program consists of water level fluctuations supplemented by herbicides. This environmental assessment evaluates several alternatives to use of grass carp, including use of water level fluctuations (drawdowns), herbicides, and mechanical harvesters. The overall target for this demonstration is to reduce aquatic vegetation in Guntersville Reservoir to about 7,000 acres. The results of this initial stocking will be closely monitored. The proposed monitoring will serve to evaluate the effectiveness of the grass carp demonstration. Because only triploid grass carp will be stocked and phased stocking will be done, any undesirable effects that monitoring might reveal should be reversible within a few years following termination of stocking. 88 refs., 1 fig., 1 tab.

  4. Preliminary comparison of the uptake of chromium-51 and zinc-65 by three species of aquatic plants from Louisiana

    SciTech Connect

    Sklar, F.H.

    1980-12-01

    Accumulation of radionuclides was much greater for duckweed (Spirodela punctata) than for larger aquatic plants of slower growth (Bacopa caroliniana and Elodea canadensis). Higher specific activity (dpm/gm) was recorded in leaves than in stems. Chromium-51 accumulation factors ranged from a low of 66 for stems of E. canadensis to a high of 436 for S. punctata fronds. Zinc-65 accumulation factors were much higher: 142 for stems of B. caroliniana and 18,118 for fronds of S. punctata. Significant reductions in zinc-65 activity in the water surrounding growing S. punctata was detected within 10 minutes.

  5. Use of Hyperspectral Remote Sensing to Evaluate Efficacy of Aquatic Plant Management

    USDA-ARS?s Scientific Manuscript database

    Invasive aquatic weeds negatively affect biodiversity, fluvial dynamics, water quality, and water storage and conveyance for a variety of human resource demands. In California’s Sacramento-San Joaquin River Delta one submersed species - Brazilian waterweed (Egeria densa) - and one floating species ...

  6. An "assemblage toxicity index" to improve characterization of effects of atrazine on aquatic plant communities

    EPA Science Inventory

    Aquatic risk assessments are made uncertain by the use of measures of effect for only one level of effect and by the use of only one percentile in sensitivity distributions for the variation of this measure of effect across an assemblage of taxa. This leaves undefined the severi...

  7. Captive bubble and sessile drop surface characterization of a submerged aquatic plant, Hydrilla verticillata

    USDA-ARS?s Scientific Manuscript database

    The surface energy parameters of the invasive aquatic weed, Hydrilla verticillata, were determined using contact angle measurements using two different methods. The abaxial and adaxial surfaces of the leaves and stem were characterized for the weed while submerged in water using captive air and octa...

  8. An "assemblage toxicity index" to improve characterization of effects of atrazine on aquatic plant communities

    EPA Science Inventory

    Aquatic risk assessments are made uncertain by the use of measures of effect for only one level of effect and by the use of only one percentile in sensitivity distributions for the variation of this measure of effect across an assemblage of taxa. This leaves undefined the severi...

  9. Vegetation development following stream/river restoration: more natural fluvial dynamics and morphology, return of aquatic and riparian plant species?

    NASA Astrophysics Data System (ADS)

    Soons, M. B.

    2012-04-01

    After centuries of human interventions in stream/river dynamics and morphology aimed at optimizing landscapes for agricultural and industrial purposes, new insights have inspired water managers to try and combine stream and river ecosystem functions with the conservation of biodiversity. Around the world, aquatic and riparian species have declined strongly due to pollution, destruction and fragmentation of their habitat, so that biodiversity conservation initiatives primarily focus on habitat restoration. In the past decades many stream and river restoration projects have been carried out and often hydrological dynamics and morphology have been restored to a more natural state. However, the successful restoration of aquatic and riparian habitats very often failed to result in restoration of their biodiversity. This lack of success from a biodiversity conservation perspective is usually attributed to 'dispersal limitation', meaning that the habitat may be restored, but species fail to reach the site and re-colonize it. Especially re-colonization by aquatic and riparian plant species is important, as such species function as ecosystem engineers: their presence alters fluvial dynamics and morphology, generates additional habitat heterogeneity and provides habitat and food for animal species. Following minor disturbances, re-colonization is often possible through locally remaining populations, by seeds in the seed bank or by surviving plant fragments. However, following major disturbances, colonization and establishment from other source populations are necessary. This usually occurs through dispersal of seeds (and in more aquatic species also by dispersal of vegetative fragments) into the restored wetland area. As dispersal occurs predominantly over short distances and source populations of aquatic and riparian species may be lacking in the surroundings, dispersal may be a limiting factor in the development of aquatic and riparian vegetation at a restored site. But

  10. Aquatic Plant Control Research Program. Growth and Rooting Depth Characteristics of Hydrilla Verticillata (L.f.) Royle and Myriophyllum Spicatum L. on Fertilized and Unfertilized Sediments

    DTIC Science & Technology

    1994-05-01

    Waisel, Y. (1986). "The ecophysiology of roots of submerged vascular plants ," Physiol. Veg. 24, 607-624. Allen, S. E., Grimshaw, H. M., Parkinson, J. A...SAS Institute, Inc. (1991). SAS Version 6.03. Cary, NC. Sculthorpe, C. D. (1967). The biology of aquatic vascular plants . Arnold, London. Short, F. T

  11. Large-Scale Operations Management Test of Use of the White Amur for Control of Problem Aquatic Plants. Report 2. First Year Poststocking Results. Volume III. The Plankton and Benthos of Lake Conway, Florida,

    DTIC Science & Technology

    1981-11-01

    several exotic plant species. These include waterhyacinth (Eichhornia crassipes), Florida elodea (Hydrilla verticillata), and Eurasian watermilfoil...LARGE-SCALE OPERATIONSm o .. MANAGEMENT TEST OF USE OFI . THE WHITE AMUR FOR CONTROL OF PROBLEM AQUATIC PLANTS . Report 2 FIRST YEAR POSTSTOCKING RESULTS...OPERATIONS MANAGEMENT TEST OF USE OF THE WHITE AMUR FOR CONTROL OF PROBLEM AQUATIC PLANTS Report I: Baseline Studies Volume I: The Aquatic Macropyes of

  12. The Link between Morphotype Transition and Virulence in Cryptococcus neoformans

    PubMed Central

    Wang, Linqi; Zhai, Bing; Lin, Xiaorong

    2012-01-01

    Cryptococcus neoformans is a ubiquitous human fungal pathogen. This pathogen can undergo morphotype transition between the yeast and the filamentous form and such morphological transition has been implicated in virulence for decades. Morphotype transition is typically observed during mating, which is governed by pheromone signaling. Paradoxically, components specific to the pheromone signaling pathways play no or minimal direct roles in virulence. Thus, the link between morphotype transition and virulence and the underlying molecular mechanism remain elusive. Here, we demonstrate that filamentation can occur independent of pheromone signaling and mating, and both mating-dependent and mating-independent morphotype transition require the transcription factor Znf2. High expression of Znf2 is necessary and sufficient to initiate and maintain sex-independent filamentous growth under host-relevant conditions in vitro and during infection. Importantly, ZNF2 overexpression abolishes fungal virulence in murine models of cryptococcosis. Thus, Znf2 bridges the sex-independent morphotype transition and fungal pathogenicity. The impacts of Znf2 on morphological switch and pathogenicity are at least partly mediated through its effects on cell adhesion property. Cfl1, a Znf2 downstream factor, regulates morphogenesis, cell adhesion, biofilm formation, and virulence. Cfl1 is the first adhesin discovered in the phylum Basidiomycota of the Kingdom Fungi. Together with previous findings in other eukaryotic pathogens, our findings support a convergent evolution of plasticity in morphology and its impact on cell adhesion as a critical adaptive trait for pathogenesis. PMID:22737071

  13. Image spectroscopy and stable isotopes elucidate functional dissimilarity between native and nonnative plant species in the aquatic environment.

    PubMed

    Santos, Maria J; Hestir, Erin L; Khanna, Shruti; Ustin, Susan L

    2012-02-01

    • Nonnative species may change ecosystem functionality at the expense of native species. Here, we examine the similarity of functional traits of native and nonnative submersed aquatic plants (SAP) in an aquatic ecosystem. • We used field and airborne imaging spectroscopy and isotope ratios of SAP species in the Sacramento-San Joaquin Delta, California (USA) to assess species identification, chlorophyll (Chl) concentration, and differences in photosynthetic efficiency. • Spectral separability between species occurs primarily in the visible and near-infrared spectral regions, which is associated with morphological and physiological differences. Nonnatives had significantly higher Chl, carotene, and anthocyanin concentrations than natives and had significantly higher photochemical reflectance index (PRI) and δ(13) C values. • Results show nonnative SAPs are functionally dissimilar to native SAPs, having wider leaf blades and greater leaf area, dense and evenly distributed vertical canopies, and higher pigment concentrations. Results suggest that nonnatives also use a facultative C(4) -like photosynthetic pathway, allowing efficient photosynthesis in high-light and low-light environments. Differences in plant functionality indicate that nonnative SAPs have a competitive advantage over native SAPs as a result of growth form and greater light-use efficiency that promotes growth under different light conditions, traits affecting system-wide species distributions and community composition. © 2011 The Authors. New Phytologist © 2011 New Phytologist Trust.

  14. Hydrogen and carbon isotopic fractionations of lipid biosynthesis among terrestrial (C3, C4 and CAM) and aquatic plants.

    PubMed

    Chikaraishi, Yoshito; Naraoka, Hiroshi; Poulson, Simon R

    2004-05-01

    Compound-specific hydrogen and carbon isotopic compositions in n-alkanoic acids, phytol and sterols were determined for various plant classes (terrestrial C3-angiosperm; C3-gymnosperm; C4; crassulacean acid metabolism (CAM); and aquatic C3 plants) in order to investigate isotopic fractionations among various plant classes. In all plants, lipid biomolecules are depleted in both D (up to 324 per thousand ) and 13C (up to 14.7 per thousand ) relative to ambient water and bulk tissue, respectively. In addition, the magnitude of D- and 13C-depletion of lipid biomolecules is distinctive depending on plant classes. For example, C3 angiosperm n-alkanoic acids are less depleted in D (95+/-23 per thousand ) and 13C (4.3 +/- 2.5 per thousand ) relative to ambient water and bulk tissue, respectively, while C4 plant n-alkanoic acids are more depleted in D (119 +/- 15 per thousand ) and 13C (10.2 +/- 2.0 per thousand ). On the other hand, C3 angiosperm phytol and sterols are much more depleted in D (306 +/-12 per thousand for phytol, 211+/-15 per thousand for sterol) with less depletion in 13C (4.1 +/- 1.1 per thousand for phytol, 1.3 +/- 0.9 per thousand for sterol) relative to ambient water and bulk tissue, respectively, while C4 plant phytol and sterols are less depleted in D (254 +/- 7 per thousand for phytol, 186 +/- 13 per thousand for sterols) with much more depletion in 13C (9.0 +/- 1.2 per thousand for phytol, 5.0 +/- 1.1 per thousand for sterols). Among various plant classes, there is a positive correlation between the D- and 13C-depletion for n-alkanoic acids, while a negative correlation was found for phytol and sterols from the same plants. Copyright 2004 Elsiever Ltd.

  15. [Low level of allozyme polymorphism in relict aquatic plants of the Far East Nelumbo komarovii Grossh. and Euryale ferox Salisb].

    PubMed

    Koren', O G; Iatsunskaia, M S; Nakonechnaia, O V

    2012-09-01

    Using allozyme analysis, genetic variation of two relict aquatic plants from Primorsky krai, Komarov lotus (Neliumbo komarovii Grossh.) and Gorgon plant (Euryale ferox Salisb.), was examined. The absence of allozyme variation in the Primorye populations of Neliumbo komarovii along with low polymorphism level in the population of Euryale ferox (P95 = 7.69; A = 1.07; Ho = 0.072; He = 0.038) was demonstrated. Since the data for the species examined are reported for the first time ever, the pheonotypes and genetic interpretation of the enzyme systems tested are presented. The izoenzyme profiles of N. komarovii were compared with the data reported for N. nucifera from China. The absence ofallozyme variation in N. komarovii, along with extremely low level of variation revealed for E. ferox, is discussed in association with the evolutionary histories of these species, their dispersal after the Pleistocene-Holocene cooling, and survival on this territory in range boundaries.

  16. Evaluation of peroxidase as a biochemical indicator of toxic chemical exposure in the aquatic plant Hydrilla verticillata, Royle

    USGS Publications Warehouse

    Byl, T.D.; Sutton, H.D.; Klaine, S.J.

    1994-01-01

    Laboratory bioassays were conducted to determine the utility of peroxidase (POD) activity as a biochemical indicator of contaminant exposure in the aquatic plant Hydrilla verticillata, Royle. The plants were exposed to anthracene, sulfometuron methyl (Oust??), Cd2+, Cr6+, Cu2+, Mn2+, and Se4+ in concentration factors of 10. POD was extracted and measured by spectrophotometric assay. There was a significant increase in POD activity after a 5-d exposure to each of the chemicals at 1 mg/L. The optimum pH for POD activity after exposure to the chemicals was 5.5 to 6.0. The increase in POD was found to be dose dependent for each of the chemicals. The lowest concentration of chemical to induce a significant POD increase was 0.01 mg/L for anthracene, Oust, Cd, Cr, and Cu; 0.1 mg/L for Se; and 1.0 mg/L for Mn.Laboratory bioassays were conducted to determine the utility of peroxidase (POD) activity as a biochemical indicator of contaminant exposure in the aquatic plant Hydrilla verticillata, Royle. The plants were exposed to anthracene, sulfometuron methyl (Oust), Cd2+, Cr6+, Cu2+, Mn2+, and Se4+ in concentration factors of 10. POD was extracted and measured by spectrophotometric assay. There was a significant increase in POD activity after a 5-d exposure to each of the chemicals at 1 mg/L. The optimum pH for POD activity after exposure to the chemicals was 5.5 to 6.0. The increase in POD was found to be dose dependent for each of the chemicals. The lowest concentration of chemical to induce a significant POD increase was 0.01 mg/L for anthracene, Oust, Cd, Cr, and Cu: 0.1 mg/L for Se; and 1.0 mg/L for Mn.

  17. Effects of Three Species of Aquatic Plants on Macroinvertebrates in Lake Seminole, Georgia

    DTIC Science & Technology

    1994-08-01

    important food source for fishes (Schramm, Jirka, and Hoyer 1987). Water - fowl have been shown to feed on macrophyte tissue and epiphytic...Introduction Macrophytes and Benthic Macroinvertebrates Aquatic macrophytes affect limnological processes in lentic and lotic habi- tats (Carpenter and Lodge...1986). Carter et al. (1988) showed that macro- phytes affected flow, water temperature, and clarity in the Potomac River in Maryland. In lacustrine

  18. 77 FR 49601 - Endangered and Threatened Wildlife and Plants; Endangered Status for Six West Texas Aquatic...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-08-16

    ...We, the U.S. Fish and Wildlife Service, propose to list as endangered and propose critical habitat for six west Texas aquatic invertebrate species under the Endangered Species Act. These actions are being taken as the result of a court-approved settlement agreement. These are proposed regulations, and if finalized the effect of these regulations will be to conserve the species and protect......

  19. A Survey of the Invasive Aquatic and Riparian Plants of the Low Rio Grande

    DTIC Science & Technology

    2005-04-01

    many areas. In 2001 and 2003, surveys were conducted starting below Amistad Reservoir to immediately below Falcon Reservoir to assess the...River were surveyed from Amistad Reservoir to Anzulduas Dam for the presence of hydrilla and other invasive aquatic weed species (Grodowitz et al...to difficulties in accessing the river. During the 2001 survey, hydrilla was found in Amistad Reservoir and below Falcon Reservoir. In August 2002

  20. Changes in growth, biochemical components, and antioxidant activity in aquatic plant Wolffia arrhiza (Lemnaceae) exposed to cadmium and lead.

    PubMed

    Piotrowska, Alicja; Bajguz, Andrzej; Godlewska-Zyłkiewicz, Beata; Zambrzycka, Elzbieta

    2010-04-01

    The present study investigated the biochemical response of aquatic plant Wolffia arrhiza (Lemnaceae) treated with lead (Pb) and cadmium (Cd) at a range of concentrations from 1 to 1000 microM. W. arrhiza has been identified as good scavenger of heavy metals from aqueous solution. Pb and Cd accumulation was found to be increased in a concentration- and duration-dependent manner. However, the highest biosorption of heavy metals was found in plants exposed to low levels (10 microM) of Cd and Pb in the nutrient medium. In observing the response to heavy-metal stress, we noted inhibited plant growth and decreased photosynthetic pigments, monosaccharides, and proteins. In addition, Cd was found to be more toxic to plants than Pb. Heavy metals also induced oxidative damage as evidenced by increased lipid peroxidation and hydrogen peroxide levels. In contrast, the deleterious effects resulting from the cellular oxidative state can be alleviated by enzymatic (catalase, ascorbate peroxidase, nicotinamide dinucleotide [NADH] peroxidase) and nonenzymatic (ascorbate, glutathione) antioxidant mechanisms activated in W. arrhiza plants exposed to Cd and Pb, especially at 10 microM. These results suggest that W. arrhiza is a promising bioindicator of heavy-metal toxicity.

  1. Bioindication of heavy metals with aquatic macrophytes: the case of a stream polluted with power plant sewages in Poland.

    PubMed

    Samecka-Cymerman, A; Kempers, A J

    2001-01-12

    The Kozi Brod (left tributary of the Biala Przemsza, east of Katowice) flows in a highly industrial coal-mining area dominated by the power plant of Siersza. Concentrations of the microelements nickel (Ni), chromium (Cr), cobalt (Co), zinc (Zn), manganese (Mn), lead (Pb), cadmium (Cd), copper (Cu), barium (Ba), aluminum (Al), vanadium (V), and strontium (Sr), as well as the macronutrients nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), iron (Fe), and sulfur (S), were measured in water and plants of the Kozi Brod. The collected plants were: Myosotis palustris L. Nathorst, Galium palustre L., Mentha rotundifolia L. Huds., Mentha aquatica L., Berula erecta (Huds.) Coville, Cardamine amara L., Epilobium angustifolium L., Geranium palustre L., Lysimachia vulgaris L., Crepis paludosa L. Much., Calitriche verna L., Solanum dulcamara L., and the aquatic moss Hygrohypnum ochraceum (Turn.) Loesk. These plants were used to evaluate the spatial distribution of elements in the Kozi Brod and contained elevated levels of Co, Cd, Zn, Ni, Mn, Al, Pb, and Cu. Significant correlations between concentrations of Cd, Zn, and Mn in water and plants indicate the potential of these species for pollution monitoring.

  2. Utilization of two invasive free-floating aquatic plants (Pistia stratiotes and Eichhornia crassipes) as sorbents for oil removal.

    PubMed

    Yang, Xunan; Chen, Shanshan; Zhang, Renduo

    2014-01-01

    Free-floating aquatic plants Pistia stratiotes and Eichhornia crassipes are well-known invasive species in the tropics and subtropics. The aim of this study was to utilize the plants as cost-effective and environmentally friendly oil sorbents. Multilevel wrinkle structure of P. stratiotes leaf (PL), rough surface of E. crassipes leaf (EL), and box structure of E. crassipes stalk (ES) were observed using the scanning electron microscope. The natural hydrophobic structures and capillary rise tests supported the idea to use P. stratiotes and E. crassipes as oil sorbents. Experiments indicated that the oil sorption by the plants was a fast process. The maximum sorption capacities for different oils reached 5.1-7.6, 3.1-4.8, and 10.6-11.7 g of oil per gram of sorbent for PL, EL, and ES, respectively. In the range of 5-35 °C, the sorption capacities of the plants were not significantly different. These results suggest that the plants can be used as efficient oil sorbents.

  3. [Correlation between aquatic plant diversity and water environment in the typical sites of Hangzhou section of the Beijing-Hangzhou Grand Canal].

    PubMed

    Lu, Yin; Xu, Xiao-Lu; Zhang, De-Yong; Wang, Li; Zhu, Xu-Ni; Feng, Feng; Zhou, Qiao-Jun; Xie, Peng

    2014-05-01

    Community characteristics of aquatic plant are important indicators for water quality. In order to understand the distribution characteristics of aquatic plants in aquatic ecosystem of the Beijing-Hangzhou Grand Canal ( Hangzhou section) , and to analyze the relationship between water quality and plant community, an investigation of the aquatic plants in five typical sites was made in this study. Species composition, biological diversity, quantity distribution and dominant species of aquatic plants in five sites were studied for ecological changes. Physicochemical factors such as temperature, pH value, transparency, dissolved oxygen and main elements of living were also analyzed. Based on the results, the distribution of phytoplankton diversity and environment factor correlations by multivariate statistical analysis were discussed. The trophic levels of these sites were assessed by using related biological standards. Results indicated that the diversity of aquatic plant mainly depends on the diversity of phytoplankton in the typical sites of the Beijing-Hangzhou Grand Canal. We observed and identified 35 genus algae, including advantage community of Hyalodiscus Ehrenberg and Melosira Agardh, which belonged to Bacillariophyta. According to the impact on the phytoplankton diversity and distribution, factors such as dissolved oxygen, transparency, water temperature, etc. had an obvious influence on the distribution of phytoplankton in the existing 6 environmental factors, while the influence of pH value was the highest. In terms of water quality eutrophication, site Tangxi Bridge and Maiyu Bridge showed a relatively lighter pollution, while site Yiqiao Bridge, Gujia Bridge and Gongchen Bridge showed a higher pollution, and the pollution of site Yiqiao Bridge was the most serious.

  4. Arsenic, Zinc, and Aluminium Removal from Gold Mine Wastewater Effluents and Accumulation by Submerged Aquatic Plants (Cabomba piauhyensis, Egeria densa, and Hydrilla verticillata)

    PubMed Central

    Yusoff, Ismail; Fatt, Ng Tham; Othman, Faridah; Ashraf, Muhammad Aqeel

    2013-01-01

    The potential of three submerged aquatic plant species (Cabomba piauhyensis, Egeria densa, and Hydrilla verticillata) to be used for As, Al, and Zn phytoremediation was tested. The plants were exposed for 14 days under hydroponic conditions to mine waste water effluents in order to assess the suitability of the aquatic plants to remediate elevated multi-metals concentrations in mine waste water. The results show that the E. densa and H. verticillata are able to accumulate high amount of arsenic (95.2%) and zinc (93.7%) and resulted in a decrease of arsenic and zinc in the ambient water. On the other hand, C. piauhyensis shows remarkable aluminium accumulation in plant biomass (83.8%) compared to the other tested plants. The ability of these plants to accumulate the studied metals and survive throughout the experiment demonstrates the potential of these plants to remediate metal enriched water especially for mine drainage effluent. Among the three tested aquatic plants, H. verticillata was found to be the most applicable (84.5%) and suitable plant species to phytoremediate elevated metals and metalloid in mine related waste water. PMID:24102060

  5. Arsenic, zinc, and aluminium removal from gold mine wastewater effluents and accumulation by submerged aquatic plants (Cabomba piauhyensis, Egeria densa, and Hydrilla verticillata).

    PubMed

    Abu Bakar, Ahmad Farid; Yusoff, Ismail; Fatt, Ng Tham; Othman, Faridah; Ashraf, Muhammad Aqeel

    2013-01-01

    The potential of three submerged aquatic plant species (Cabomba piauhyensis, Egeria densa, and Hydrilla verticillata) to be used for As, Al, and Zn phytoremediation was tested. The plants were exposed for 14 days under hydroponic conditions to mine waste water effluents in order to assess the suitability of the aquatic plants to remediate elevated multi-metals concentrations in mine waste water. The results show that the E. densa and H. verticillata are able to accumulate high amount of arsenic (95.2%) and zinc (93.7%) and resulted in a decrease of arsenic and zinc in the ambient water. On the other hand, C. piauhyensis shows remarkable aluminium accumulation in plant biomass (83.8%) compared to the other tested plants. The ability of these plants to accumulate the studied metals and survive throughout the experiment demonstrates the potential of these plants to remediate metal enriched water especially for mine drainage effluent. Among the three tested aquatic plants, H. verticillata was found to be the most applicable (84.5%) and suitable plant species to phytoremediate elevated metals and metalloid in mine related waste water.

  6. Co-occurrence of the Cyanotoxins BMAA, DABA and Anatoxin-a in Nebraska Reservoirs, Fish, and Aquatic Plants

    PubMed Central

    Al-Sammak, Maitham Ahmed; Hoagland, Kyle D.; Cassada, David; Snow, Daniel D.

    2014-01-01

    Several groups of microorganisms are capable of producing toxins in aquatic environments. Cyanobacteria are prevalent blue green algae in freshwater systems, and many species produce cyanotoxins which include a variety of chemical irritants, hepatotoxins and neurotoxins. Production and occurrence of potent neurotoxic cyanotoxins β-N-methylamino-l-alanine (BMAA), 2,4-diaminobutyric acid dihydrochloride (DABA), and anatoxin-a are especially critical with environmental implications to public and animal health. Biomagnification, though not well understood in aquatic systems, is potentially relevant to both human and animal health effects. Because little is known regarding their presence in fresh water, we investigated the occurrence and potential for bioaccumulation of cyanotoxins in several Nebraska reservoirs. Collection and analysis of 387 environmental and biological samples (water, fish, and aquatic plant) provided a snapshot of their occurrence. A sensitive detection method was developed using solid phase extraction (SPE) in combination with high pressure liquid chromatography-fluorescence detection (HPLC/FD) with confirmation by liquid chromatography-tandem mass spectrometry (LC/MS/MS). HPLC/FD detection limits ranged from 5 to 7 µg/L and LC/MS/MS detection limits were <0.5 µg/L, while detection limits for biological samples were in the range of 0.8–3.2 ng/g depending on the matrix. Based on these methods, measurable levels of these neurotoxic compounds were detected in approximately 25% of the samples, with detections of BMAA in about 18.1%, DABA in 17.1%, and anatoxin-a in 11.9%. PMID:24476710

  7. Co-occurrence of the cyanotoxins BMAA, DABA and anatoxin-a in Nebraska reservoirs, fish, and aquatic plants.

    PubMed

    Al-Sammak, Maitham Ahmed; Hoagland, Kyle D; Cassada, David; Snow, Daniel D

    2014-01-28

    Several groups of microorganisms are capable of producing toxins in aquatic environments. Cyanobacteria are prevalent blue green algae in freshwater systems, and many species produce cyanotoxins which include a variety of chemical irritants, hepatotoxins and neurotoxins. Production and occurrence of potent neurotoxic cyanotoxins β-N-methylamino-L-alanine (BMAA), 2,4-diaminobutyric acid dihydrochloride (DABA), and anatoxin-a are especially critical with environmental implications to public and animal health. Biomagnification, though not well understood in aquatic systems, is potentially relevant to both human and animal health effects. Because little is known regarding their presence in fresh water, we investigated the occurrence and potential for bioaccumulation of cyanotoxins in several Nebraska reservoirs. Collection and analysis of 387 environmental and biological samples (water, fish, and aquatic plant) provided a snapshot of their occurrence. A sensitive detection method was developed using solid phase extraction (SPE) in combination with high pressure liquid chromatography-fluorescence detection (HPLC/FD) with confirmation by liquid chromatography-tandem mass spectrometry (LC/MS/MS). HPLC/FD detection limits ranged from 5 to 7 µg/L and LC/MS/MS detection limits were <0.5 µg/L, while detection limits for biological samples were in the range of 0.8-3.2 ng/g depending on the matrix. Based on these methods, measurable levels of these neurotoxic compounds were detected in approximately 25% of the samples, with detections of BMAA in about 18.1%, DABA in 17.1%, and anatoxin-a in 11.9%.

  8. Microbial Community Analysis in the Roots of Aquatic Plants and Isolation of Novel Microbes Including an Organism of the Candidate Phylum OP10

    PubMed Central

    Tanaka, Yasuhiro; Tamaki, Hideyuki; Matsuzawa, Hiroaki; Nigaya, Masahiro; Mori, Kazuhiro; Kamagata, Yoichi

    2012-01-01

    A number of molecular ecological studies have revealed complex and unique microbial communities in various terrestrial plant roots; however, little is known about the microbial communities of aquatic plant roots in spite of their potential use for water quality improvement in aquatic environments (e.g. floating treatment wetland system). Here, we report the microbial communities inhabiting the roots of emerged plants, reed (Phragmites australis) and Japanese loosestrife (Lythrum anceps), collected from a floating treatment wetland in a pond by both culture-independent and culture-dependent approaches. Culture-independent analysis based on 16S rRNA gene sequences revealed that the microbial compositions between the two aquatic plant roots were clearly different (e.g. the predominant microbe was Betaproteobacteria for reed and Alphaproteobacteria for Japanese loosestrife). In comparisons of microbial communities between the plant roots and pond water taken from near the plants, the microbial diversity in the plant roots (e.g. 4.40–4.26 Shannon-Weiner index) were higher than that of pond water (e.g. 3.15 Shannon-Weiner index). Furthermore, the plant roots harbored 2.5–3.5 times more phylogenetically novel clone phylotypes than pond water. The culture-dependent approach also revealed differences in the microbial composition and diversity among the two plant roots and pond water. More importantly, compared to pond water, we succeeded in isolating approximately two times more novel isolate phylotypes, including a bacterium of candidate phylum OP10 (recently named Armatimonadetes) from the plant roots. These findings suggest that aquatic plants roots are significant sources for a variety of novel organisms. PMID:22791047

  9. Microbial community analysis in the roots of aquatic plants and isolation of novel microbes including an organism of the candidate phylum OP10.

    PubMed

    Tanaka, Yasuhiro; Tamaki, Hideyuki; Matsuzawa, Hiroaki; Nigaya, Masahiro; Mori, Kazuhiro; Kamagata, Yoichi

    2012-01-01

    A number of molecular ecological studies have revealed complex and unique microbial communities in various terrestrial plant roots; however, little is known about the microbial communities of aquatic plant roots in spite of their potential use for water quality improvement in aquatic environments (e.g. floating treatment wetland system). Here, we report the microbial communities inhabiting the roots of emerged plants, reed (Phragmites australis) and Japanese loosestrife (Lythrum anceps), collected from a floating treatment wetland in a pond by both culture-independent and culture-dependent approaches. Culture-independent analysis based on 16S rRNA gene sequences revealed that the microbial compositions between the two aquatic plant roots were clearly different (e.g. the predominant microbe was Betaproteobacteria for reed and Alphaproteobacteria for Japanese loosestrife). In comparisons of microbial communities between the plant roots and pond water taken from near the plants, the microbial diversity in the plant roots (e.g. 4.40-4.26 Shannon-Weiner index) were higher than that of pond water (e.g. 3.15 Shannon-Weiner index). Furthermore, the plant roots harbored 2.5-3.5 times more phylogenetically novel clone phylotypes than pond water. The culture-dependent approach also revealed differences in the microbial composition and diversity among the two plant roots and pond water. More importantly, compared to pond water, we succeeded in isolating approximately two times more novel isolate phylotypes, including a bacterium of candidate phylum OP10 (recently named Armatimonadetes) from the plant roots. These findings suggest that aquatic plants roots are significant sources for a variety of novel organisms.

  10. Generic phylogeny, historical biogeography and character evolution of the cosmopolitan aquatic plant family Hydrocharitaceae.

    PubMed

    Chen, Ling-Yun; Chen, Jin-Ming; Gituru, Robert Wahiti; Wang, Qing-Feng

    2012-03-10

    Hydrocharitaceae is a fully aquatic monocot family, consists of 18 genera with approximately 120 species. The family includes both fresh and marine aquatics and exhibits great diversity in form and habit including annual and perennial life histories; submersed, partially submersed and floating leaf habits and linear to orbicular leaf shapes. The family has a cosmopolitan distribution and is well represented in the Tertiary fossil record in Europe. At present, the historical biogeography of the family is not well understood and the generic relationships remain controversial. In this study we investigated the phylogeny and biogeography of Hydrocharitaceae by integrating fossils and DNA sequences from eight genes. We also conducted ancestral state reconstruction for three morphological characters. Phylogenetic analyses produced a phylogeny with most branches strongly supported by bootstrap values greater than 95 and Bayesian posterior probability values of 1.0. Stratiotes is the first diverging lineage with the remaining genera in two clades, one clade consists of Lagarosiphon, Ottelia, Blyxa, Apalanthe, Elodea and Egeria; and the other consists of Hydrocharis-Limnobium, Thalassia, Enhalus, Halophila, Najas, Hydrilla, Vallisneria, Nechamandra and Maidenia. Biogeographic analyses (DIVA, Mesquite) and divergence time estimates (BEAST) resolved the most recent common ancestor of Hydrocharitaceae as being in Asia during the Late Cretaceous and Palaeocene (54.7-72.6 Ma). Dispersals (including long-distance dispersal and migrations through Tethys seaway and land bridges) probably played major roles in the intercontinental distribution of this family. Ancestral state reconstruction suggested that in Hydrocharitaceae evolution of dioecy is bidirectional, viz., from dioecy to hermaphroditism, and from hermaphroditism to dioecy, and that the aerial-submerged leaf habit and short-linear leaf shape are the ancestral states. Our study has shed light on the previously controversial

  11. Monitoring heavy metal pollution by aquatic plants: a systematic study of copper uptake.

    PubMed

    Materazzi, S; Canepari, S; Aquili, S

    2012-09-01

    The copper bioaccumulation by the floating Lemna minor and by the completely submerged Ranunculus tricophyllus as a function of exposure time and copper concentration was studied, with the aim of proposing these species as environmental biosensors of the water pollution. The results show that both these aquatic angiosperms are good indicators of copper pollution because the copper uptake is the only function of metal concentration (water pollution). Uptake behavior is reported as a function of the time and concentration, based on the results of a 3-year study. Kinetic evaluations are proposed.

  12. The toxic effects of l-Cysteine-capped cadmium sulfide nanoparticles on the aquatic plant Spirodela polyrrhiza

    NASA Astrophysics Data System (ADS)

    Khataee, Alireza; Movafeghi, Ali; Nazari, Fatemeh; Vafaei, Fatemeh; Dadpour, Mohammad Reza; Hanifehpour, Younes; Joo, Sang Woo

    2014-12-01

    Plants play an important role in the fate of nanoparticles in the environment through their uptake, bioaccumulation, and transfer to trophic chains. However, the impacts of nanoparticles on plants as essential components of all ecosystems are not well documented. In the present study, the toxic effects of l-Cysteine-capped CdS nanoparticles on Spirodela polyrrhiza as an aquatic higher plant species were studied. l-Cysteine-capped CdS nanoparticles were synthesized using hydrothermal method and their characteristics were determined by XRD, SEM, HR-TEM, and FT-IR techniques. The diameter of majority of synthesized nanoparticles was about 15-20 nm. Subsequently, the uptake of l-Cysteine-capped CdS nanoparticles by the plant species was confirmed using epifluorescence microscopy. The activity of peroxidase and superoxide dismutase as antioxidant enzymes was assayed and the relative frond number was calculated in the presence of different concentrations of l-Cysteine-capped CdS nanoparticles. The obtained results revealed the toxic effects of the synthesized nanoparticles on S. polyrrhiza, leading to growth reduction and significant changes in antioxidant enzymes' activity.

  13. Cylindrospermopsin inhibits growth and modulates protease activity in the aquatic plants Lemna minor L. and Wolffia arrhiza (L.) Horkel.

    PubMed

    Jámbrik, Katalin; Máthé, C; Vasas, G; Bácsi, I; Surányi, G; Gonda, S; Borbély, G; M-Hamvas, Márta

    2010-01-01

    The toxic effects of cylindrospermopsin (cyanobacterial toxin) on animals have been examined extensively, but little research has focused on their effects on plants. In this study cylindrospermopsin (CYN) caused alterations of growth, soluble protein content and protease enzyme activity were studied on two aquatic plants Lemna minor and Wolffia arrhiza in short-term (5 days) experiments. For the treatments we used CYN containing crude extracts of Aphanizomenon ovalisporum (BGSD-423) and purified CYN as well. The maximal inhibitory effects on fresh weight of L. minor and W. arrhiza caused by crude extract were 60% and 54%, respectively, while the maximum inhibitory effects were 30% and 43% in the case of purified CYN at 20 μg ml(-1) CYN content of culture medium. In CYN-treated plants the concentration of soluble protein showed mild increases, especially in W. arrhiza. Protease isoenzyme activity gels showed significant alterations of enzyme activities under the influence of CYN. Several isoenzymes were far more active and new ones appeared in CYN-treated plants. Treatments with cyanobacterial crude extract caused stronger effects than the purified cyanobacterial toxins used in equivalent CYN concentrations.

  14. Fate of Flumioxazin in Aquatic Plants: Two Algae (Pseudokirchneriella subcapitata, Synechococcus sp.), Duckweed (Lemna sp.), and Water Milfoil (Myriophyllum elatinoides).

    PubMed

    Ando, Daisuke; Fujisawa, Takuo; Katagi, Toshiyuki

    2017-09-26

    Flumioxazin separately (14)C-labeled at 1,2-positions of the tetrahydrophthalimide moiety or uniformly labeled at the phenyl ring was exposed to two algae and duckweed via the water layer and water milfoil via the water layer or bottom sediment for 14 days to investigate uptake and metabolic profiles in these aquatic plants. While (14)C-flumioxazin received immediate hydrolysis through maleimide ring opening and amide bond cleavage with its hydrolytic half-life of <1 day in both water and sediment, the (14)C-plant uptake was ≤4.7% of the applied radioactivity (%AR) with water exposure for all plants and 0.9%AR with sediment exposure for water milfoil. No (14)C-translocation between shoot/leaves and roots occurred in water milfoil. The components of (14)C residues in plants were common among the species, which were the above hydrolysates and their transformation products, that is, dicarboxylic acid derivative metabolized via hydroxylation at the double bond of the cyclohexene ring followed by sugar conjugation with its counterpart amine derivative via acid conjugations.

  15. A weight-of-evidence approach for deriving a level of concern for atrazine that is protective of aquatic plant communities.

    PubMed

    Moore, Dwayne Rj; Greer, Colleen D; Manning, Gillian; Wooding, Katie; Beckett, Kerrie J; Brain, Richard A; Marshall, Gary

    2017-07-01

    Atrazine is a selective triazine herbicide widely used in the United States primarily for control of broadleaf weeds in corn and sorghum. In 2003, the US Environmental Protection Agency (USEPA) concluded that atrazine poses potential risks to sensitive aquatic species. Consequently, a surface water monitoring program was developed to assess whether measured levels of atrazine could impact aquatic plants in vulnerable watersheds. To facilitate evaluation of the monitoring data, the Agency needed to establish a level of concern (LOC) below which atrazine would not cause unacceptable adverse effects to aquatic plant communities. Several attempts at developing a community-level LOC have followed from USEPA but none have been formally accepted or endorsed by independent Scientific Advisory Panels. As part of registration review, the USEPA needs to revisit development of a community-level LOC for atrazine that will be protective of aquatic plant communities. This article reviews 4 methods that can or have been used for this purpose. Collectively, the methods take advantage of the large number of single species and mesocosm studies that have been conducted for aquatic plants exposed to atrazine. The Plant Assemblage Toxicity Index (PATI) and the Comprehensive Aquatic Systems Model for atrazine (CASMATZ2 ) incorporate single-species toxicity data but are calibrated with micro- and mesocosm study results to calculate community-level LOCs. The Brock et al. scoring system relies exclusively on mesocosm studies. Single-species toxicity data were used in a modified version of the USEPA's Water Quality Criteria (WQC) method. The 60-day LOCs calculated using the 4 methods ranged from 19.6 to 26 µg/L. A weight-of-evidence assessment indicated that the CASMATZ2 method was the most environmentally relevant and statistically reliable method. Using all 4 methods with weights based on method reliability, the weighted 60-day LOC was 23.6 µg/L. Integr Environ Assess Manag 2017

  16. An experimental study into the influence of aquatic plant motion characteristics on the generation of a fluvial turbulent flow field

    NASA Astrophysics Data System (ADS)

    Hardy, R. J.; Marjoribanks, T.; Parsons, D. R.; Thomas, R. E.

    2015-12-01

    Aquatic vegetation has a determining effect on flow and consequently sediment transport as it generates both skin friction and form drag. The measurement of flow above the vegetation canopy has received much attention and there is now a good process understanding of mean and turbulent flow, although, much of this research has focused on rigid vegetation with relatively simple morphology. However, vegetation immersed in a flow experiences several forces (buoyancy; drag; virtual mass; Basset; and Saffman) which are counteracted by the properties of the vegetation (flexural rigidity; modulus of elasticity; the plant area exposed to the flow and; the packing density of the stems). The ratio of these forces determines the plant motion characteristics which are generally classified as either i) erect with no movement; ii) gently swaying; iii) strong, coherent swaying or; iv) prone. Here we report on an investigation into the influence of plant motion on the turbulence structure in the mixing zone as vortices in this region have been shown to account for the majority of the momentum transport between the canopy and the open flow. We report on a series of flume experiments where flow over a canopy of surrogate aquatic vegetation was measured using PIV at a spatial resolution of ~1mm2 and at a temporal resolution of 100 Hz. This provided whole flow field measurements for all three components of flow over the vegetation canopy. Plant motion characteristics were altered by modifying the flow Reynolds number through both velocity and depth. The influences of plant stem length were also assessed. The measured flows were analysed by standard Reynolds decomposition approaches and Eulerian and Lagrangian coherent flow structure identification methods. Kelvin-Helmholtz and Görtler-type vortices were identified within the canopy shear layer that are generated close to the canopy top and evolve downstream into span-wise roller vortices, which expand with both distance and time. When

  17. Integument and defence in larva and prepupa of a sawfly living on a semi-aquatic plant

    NASA Astrophysics Data System (ADS)

    Boevé, Jean-Luc; Voigt, Dagmar; Gorb, Stanislav N.

    2013-01-01

    The larvae of the sawfly Rhadinoceraea micans live and feed on a semi-aquatic plant, Iris pseudacorus, and their integument is strongly hydrophobic. The hydrophobicity is part of a chemical defence strategy, easy bleeding, also known from congeners. The prepupae burrow into the soil where they form a cocoon in which they pupate, thus implying different micro-environmental conditions. The cuticle structure and wetting defensive effectiveness of R. micans were compared between larvae and prepupae. The two stages were similarly well defended against attacking ants by the bleeding of a deterrent hemolymph, whereas they were dissimilar in the cuticle surface that presented sculptures and wax crystals at the larval stage only. The integument of prepupae was less structured, and hydrophilic. Larvae of R. micans exhibit, among sawflies, an exceptional cuticle structuring and we assume that they occupy this particular niche of a semi-aquatic environment to avoid encounters with ground-dwelling predators whereas prepupae may benefit from the chemical defence acquired at larval stage.

  18. Large-Scale Operations Management Test of Use of the White Amur for Control of Problem Aquatic Plants. Report 2. First Year Poststocking Results. Volume II. The Fish, Mammals, and Waterfowl of Lake Conway, Florida.

    DTIC Science & Technology

    1982-02-01

    waterfowl and wading birds , and aquatic mammal populations on Lake Conway were surveyed for 1 year after the introduction of the herbivorous fish, white...of a series of reports documenting a large-scale operations management test of use of the white amur for control of problem aquatic plants in Lake... Manager of the Aquatic Plant Control Research Program, EL. The study was under the general supervision of Mr. B. 0. Benn, Chief, Environmental Systems

  19. Uptake of 210Po by aquatic plants of a fresh water ecosystem around the uranium mill tailings management facility of Jaduguda, India.

    PubMed

    Jha, V N; Tripathi, R M; Sethy, N K; Sahoo, S K; Puranik, V D

    2013-10-01

    The present study was designed to investigate the uptake of Polonium-210 ((210)Po) by aquatic plants growing in a fresh water ecosystem around the tailings management facility of the uranium industry of Jaduguda, India. Evaluation of the activity concentration of (210)Po in aquatic plants, the concentration ratio of (210)Po from substrate to plants and the relationship of (210)Po with other stable elements were major objectives of the investigation. Based on the habitat, three types of plant were collected and analyzed for (210)Po activity estimation. Along with aquatic plants, effluent, surface water and bottom sediment were also collected and analyzed for (210)Po activity content. From the acid solution (210)Po was electrodeposited on brightly polished silver discs and counted for alpha activity in an alpha counter. The highest (210)Po activity concentration (4884 Bq kg(-1) fresh weight) was found in filamentous algae from residual water of the tailings pond. For sediment-rooted plants, a significant positive correlation (r = 0.91, p < 0.0001) was observed between plant and sediment activity concentration of (210)Po. For all of the three different groups of plants studied, highly significant correlations were observed between activity concentration of (210)Po and Cu with the significance level variation between 0.00-0.05 (both for linear and log transformed data).

  20. Genome Sequence of the Pattern-Forming Social Bacterium Paenibacillus dendritiformis C454 Chiral Morphotype

    PubMed Central

    Sirota-Madi, Alexandra; Olender, Tsviya; Helman, Yael; Brainis, Ina; Finkelshtein, Alin; Roth, Dalit; Hagai, Efrat; Leshkowitz, Dena; Brodsky, Leonid; Galatenko, Vladimir; Nikolaev, Vladimir; Gutnick, David L.; Lancet, Doron

    2012-01-01

    Paenibacillus dendritiformis is a Gram-positive, soil-dwelling, spore-forming social microorganism. An intriguing collective faculty of this strain is manifested by its ability to switch between different morphotypes, such as the branching (T) and the chiral (C) morphotypes. Here we report the 6.3-Mb draft genome sequence of the P. dendritiformis C454 chiral morphotype. PMID:22461558

  1. Monitoring of arsenic in aquatic plants, water, and sediment of wastewater treatment ponds at the Mae Moh Lignite power plant, Thailand.

    PubMed

    Nateewattana, Jomjun; Trichaiyaporn, Siripen; Saouy, Maliwan; Nateewattana, Jintapat; Thavornyutikarn, Prasak; Pengchai, Petch; Choonluchanon, Somporn

    2010-06-01

    Mae Moh is a risky area for arsenic contamination caused by the effluent from biowetland ponds in Mae Moh lignite-fuelled power plant. The objective of this study was to investigate the arsenic concentrations of Mae Moh biowetland ponds and determine the main factors which are important for arsenic phytoremediation in the treatment system. The result revealed that arsenic concentrations in the supernant were in the range of less than 1.0 microg As L(-1) to 2.0 microg As L(-1) while those in the sediment were in the range of 25-200 microg As kg soil(-1). Both values were below the Thailand national standard of 0.25 mg As L(-1) for water and 27 mg As kg soil(-1) for the soil. Arsenic accumulation in the biomass of 5 aquatic plants at the biowetland ponds ranged from 123.83 to 280.53 mg As kgPlant(-1). Regarding the result of regression analysis (R (2) = 0.474 to 0.954), high concentrations of organic matter and other soluble ions as well as high pH value in the sediment could significantly enhance the removal of soluble arsenic in the wetland ponds. From the regression equation of accumulated arsenic concentration in each aquatic plant, Eichhornia crassipes (Mart.) Solms. (R (2) = 0.954), Ipomoea aquatica Forsk. (R (2) = 0.850), and Typha angustifolia (L.) (R (2) = 0.841) were found to be preferable arsenic removers for wastewater treatment pond in the condition of low Eh value and high content of solid phase EC and phosphorus. On the other hand, Canna glauca (L.) (R (2) = 0.749) appeared to be favorable arsenic accumulator for the treatment pond in the condition of high Eh value and high concentration of soluble EC.

  2. Delineation of sympatric morphotypes of lake trout in Lake Superior

    USGS Publications Warehouse

    Moore, Seth A.; Bronte, Charles R.

    2001-01-01

    Three morphotypes of lake trout Salvelinus namaycush are recognized in Lake Superior: lean, siscowet, and humper. Absolute morphotype assignment can be difficult. We used a size-free, whole-body morphometric analysis (truss protocol) to determine whether differences in body shape existed among lake trout morphotypes. Our results showed discrimination where traditional morphometric characters and meristic measurements failed to detect differences. Principal components analysis revealed some separation of all three morphotypes based on head and caudal peduncle shape, but it also indicated considerable overlap in score values. Humper lake trout have smaller caudal peduncle widths to head length and depth characters than do lean or siscowet lake trout. Lean lake trout had larger head measures to caudal widths, whereas siscowet had higher caudal peduncle to head measures. Backward stepwise discriminant function analysis retained two head measures, three midbody measures, and four caudal peduncle measures; correct classification rates when using these variables were 83% for leans, 80% for siscowets, and 83% for humpers, which suggests the measures we used for initial classification were consistent. Although clear ecological reasons for these differences are not readily apparent, patterns in misclassification rates may be consistent with evolutionary hypotheses for lake trout within the Laurentian Great Lakes.

  3. Fungal communities in mycorrhizal roots of conifer seedlings in forest nurseries under different cultivation systems, assessed by morphotyping, direct sequencing and mycelial isolation.

    PubMed

    Menkis, Audrius; Vasiliauskas, Rimvydas; Taylor, Andrew F S; Stenlid, Jan; Finlay, Roger

    2005-12-01

    Fungi colonising root tips of Pinus sylvestris and Picea abies grown under four different seedling cultivation systems were assessed by morphotyping, direct sequencing and isolation methods. Roots were morphotyped using two approaches: (1) 10% of the whole root system from 30 seedlings of each species and (2) 20 randomly selected tips per plant from 300 seedlings of each species. The first approach yielded 15 morphotypes, the second yielded 27, including 18 new morphotypes. The overall community consisted of 33 morphotypes. The level of mycorrhizal colonisation of roots determined by each approach was about 50%. The cultivation system had a marked effect on the level of mycorrhizal colonisation. In pine, the highest level of colonisation (48%) was observed in bare-root systems, while in spruce, colonisation was highest in polyethylene rolls (71%). Direct internal transcribed spacer ribosomal DNA sequencing and isolation detected a total of 93 fungal taxa, including 27 mycorrhizal. A total of 71 (76.3%) fungi were identified at least to a genus level. The overlap between the two methods was low. Only 13 (13.9%) of taxa were both sequenced and isolated, 47 (50.5%) were detected exclusively by sequencing and 33 (35.5%) exclusively by isolation. All isolated mycorrhizal fungi were also detected by direct sequencing. Characteristic mycorrhizas were Phialophora finlandia, Amphinema byssoides, Rhizopogon rubescens, Suillus luteus and Thelephora terrestris. There was a moderate similarity in mycorrhizal communities between pine and spruce and among different cultivation systems.

  4. Protistan predation interferes with bacterial long-term adaptation to substrate restriction by selecting for defence morphotypes.

    PubMed

    Baumgartner, M; Neu, T R; Blom, J F; Pernthaler, J

    2016-11-01

    Bacteria that are introduced into aquatic habitats face a low substrate environment interspersed with rare productive 'hotspots', as well as high protistan grazing. Whereas the former condition should select for growth performance, the latter should favour traits that reduce predation mortality, such as the formation of large cell aggregates. However, protected morphotypes often convey a growth disadvantage, and bacteria thus face a trade-off between investing in growth or defence traits. We set up an evolutionary experiment with the freshwater isolate Sphingobium sp. strain Z007 that conditionally increases aggregate formation in supernatants from a predator-prey coculture. We hypothesized that low substrate levels would favour growth performance and reduce the aggregated subpopulation, but that the concomitant presence of a flagellate predator might conserve the defence trait. After 26 (1-week) growth cycles either with (P+) or without (P-) predators, bacteria had evolved into strikingly different phenotypes. Strains from P- had low numbers of aggregates and increased growth yield, both at the original rich growth conditions and on various single carbon sources. By contrast, isolates from the P+ treatment formed elevated proportions of defence morphotypes, but exhibited lower growth yield and metabolic versatility. Moreover, the evolved strains from both treatments had lost phenotypic plasticity of aggregate formation. In summary, the (transient) residence of bacteria at oligotrophic conditions may promote a facultative oligotrophic life style, which is advantageous for survival in aquatic habitats. However, the investment in defence against predation mortality may constrain microbial adaptation to the abiotic environment.

  5. Using solid 13C NMR coupled with solution 31P NMR spectroscopy to investigate molecular species and lability of organic carbon and phosphorus from aquatic plants in Tai Lake, China

    USDA-ARS?s Scientific Manuscript database

    Aquatic plants are involved in the storage and release capacity for organic matter and nutrients. In this study, solid 13C and solution 31P nuclear magnetic resonance (NMR) spectroscopy were used to characterize the biomass samples of six aquatic plants. Solid 13C NMR spectroscopy revealed the domin...

  6. Generic phylogeny, historical biogeography and character evolution of the cosmopolitan aquatic plant family Hydrocharitaceae

    PubMed Central

    2012-01-01

    Background Hydrocharitaceae is a fully aquatic monocot family, consists of 18 genera with approximately 120 species. The family includes both fresh and marine aquatics and exhibits great diversity in form and habit including annual and perennial life histories; submersed, partially submersed and floating leaf habits and linear to orbicular leaf shapes. The family has a cosmopolitan distribution and is well represented in the Tertiary fossil record in Europe. At present, the historical biogeography of the family is not well understood and the generic relationships remain controversial. In this study we investigated the phylogeny and biogeography of Hydrocharitaceae by integrating fossils and DNA sequences from eight genes. We also conducted ancestral state reconstruction for three morphological characters. Results Phylogenetic analyses produced a phylogeny with most branches strongly supported by bootstrap values greater than 95 and Bayesian posterior probability values of 1.0. Stratiotes is the first diverging lineage with the remaining genera in two clades, one clade consists of Lagarosiphon, Ottelia, Blyxa, Apalanthe, Elodea and Egeria; and the other consists of Hydrocharis-Limnobium, Thalassia, Enhalus, Halophila, Najas, Hydrilla, Vallisneria, Nechamandra and Maidenia. Biogeographic analyses (DIVA, Mesquite) and divergence time estimates (BEAST) resolved the most recent common ancestor of Hydrocharitaceae as being in Asia during the Late Cretaceous and Palaeocene (54.7-72.6 Ma). Dispersals (including long-distance dispersal and migrations through Tethys seaway and land bridges) probably played major roles in the intercontinental distribution of this family. Ancestral state reconstruction suggested that in Hydrocharitaceae evolution of dioecy is bidirectional, viz., from dioecy to hermaphroditism, and from hermaphroditism to dioecy, and that the aerial-submerged leaf habit and short-linear leaf shape are the ancestral states. Conclusions Our study has shed light

  7. Assessment of aquatic plants in the reservoirs of AES-tietê and development of an integrated control model for the most important species.

    PubMed

    Velini, Edivaldo Domingues; Galo, Maria Lourdes B T; Carvalho, Fernando Tadeu; Martins, Dagoberto; Cavenaghi, Anderson Luis; Trindade, Maria Lúcia Bueno; Bravin, Luis Fernando N; Negrisoli, Eduardo; Antuniassi, Ulisses Rocha; Simionato, José L A; Santos, Silvio C A

    2005-01-01

    The general objective of this work was to develop a monitoring and management model for aquatic plants that could be used in reservoir cascades in Brazil, using the reservoirs of AES-Tietê as a study case. The investigations were carried out at the reservoirs of Barra-Bonita, Bariri, Ibitinga, Promissão, and Nova-Avanhandava, located in the Tietê River Basin; Agua Vermelha, located in the Grande River Basin; Caconde, Limoeiro, and Euclides da Cunha, which are part of the Pardo River Basin; and the Mogi-Guaçu reservoir, which belongs to the Mogi-Guaçu River basin. The main products of this work were: development of techniques using satellite-generated images for monitoring and planning aquatic plant control; planning and construction of a boat to move coating plant masses and an airboat equipped with a DGPS navigation and application flow control system. Results allowed to conclude that the occurrence of all types of aquatic plants is directly associated with sedimentation process and, consequently, with nutrient and light availability. Reservoirs placed at the beginning of cascades are more subject to sedimentation and occurrence of marginal, floating and emerged plants, and are the priority when it comes to controlling these plants, since they provide a supply of weeds for the other reservoirs. Reservoirs placed downstream show smaller amounts of water-suspended solids, with greater transmission of light and occurrence of submerged plants.

  8. 33 CFR Appendix B to Part 273 - Information Requirements for Aquatic Plant Control Program Reports

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... identification by common and scientific name of the plant or plants concerned, origin of infestation and likely... control operations or engineering works, including control methods, materials, equipment and procedures... operation control, the report should include a brief statement of the special problems in control methods...

  9. 33 CFR Appendix B to Part 273 - Information Requirements for Aquatic Plant Control Program Reports

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... identification by common and scientific name of the plant or plants concerned, origin of infestation and likely... control operations or engineering works, including control methods, materials, equipment and procedures... operation control, the report should include a brief statement of the special problems in control methods...

  10. Competition for light and nutrients in layered communities of aquatic plants.

    PubMed

    van Gerven, Luuk P A; de Klein, Jeroen J M; Gerla, Daan J; Kooi, Bob W; Kuiper, Jan J; Mooij, Wolf M

    2015-07-01

    Dominance of free-floating plants poses a threat to biodiversity in many freshwater ecosystems. Here we propose a theoretical framework to understand this dominance, by modeling the competition for light and nutrients in a layered community of floating and submerged plants. The model shows that at high supply of light and nutrients, floating plants always dominate due to their primacy for light, even when submerged plants have lower minimal resource requirements. The model also shows that floating-plant dominance cannot be an alternative stable state in light-limited environments but only in nutrient-limited environments, depending on the plants' resource consumption traits. Compared to unlayered communities, the asymmetry in competition for light-coincident with symmetry in competition for nutrients-leads to fundamentally different results: competition outcomes can no longer be predicted from species traits such as minimal resource requirements ([Formula: see text] rule) and resource consumption. Also, the same two species can, depending on the environment, coexist or be alternative stable states. When applied to two common plant species in temperate regions, both the model and field data suggest that floating-plant dominance is unlikely to be an alternative stable state.

  11. Carbon-Flow-Based Modeling of Ecophysiological Processes and Biomass Dynamics of Submersed Aquatic Plants

    DTIC Science & Technology

    2007-09-01

    Vallisneria americana [model VALLA], Potamogeton pectinatus [POTAM], Hydrilla verticillata [HYDRIL], and Myriophyllum spicatum [MILFO]. These plant...hydrilla)-HYDRIL, and Myriophyllum spicatum (Eurasian watermilfoil)-MILFO. These plant species are similar in growth strategy, but they differ...90 References Adams, M. S., and M. D. McCracken. 1974. Seasonal production of the Myriophyllum component of the littoral of Lake Wingra

  12. Paleomycology of the Princeton Chert II. Dark-septate fungi in the aquatic angiosperm Eorhiza arnoldii indicate a diverse assemblage of root-colonizing fungi during the Eocene.

    PubMed

    Klymiuk, Ashley A; Taylor, Thomas N; Taylor, Edith L; Krings, Michael

    2013-01-01

    Tissues of the extinct aquatic or emergent angiosperm, Eorhiza arnoldii incertae sedis, were extensively colonized by microfungi, and in this study we report the presence of several types of sterile mycelia. In addition to inter- and intracellular proliferation of regular septate hyphae, the tissues contain monilioid hyphae with intercalary branching. These filamentous mycelia are spatially associated with two distinct morphotypes of intracellular microsclerotia. These quiescent structures are morphologically similar to loose and cerebriform microsclerotia found within the living tissues of some plants, which have been attributed to an informal assemblage of dematiaceous ascomycetes, the dark-septate endophytes. While there are significant challenges to interpreting the ecology of fossilized fungi, these specimens provide evidence for asymptomatic endophytic colonization of the rooting structures of a 48.7 million year old aquatic angiosperm.

  13. Molecular Species Delimitation and Morphology of Aquatic and Sub-Aquatic Bugs (Heteroptera) in Cameroon.

    PubMed

    Meyin A Ebong, Solange; Petit, Elsa; Le Gall, Philippe; Chen, Ping-Ping; Nieser, Nico; Guilbert, Eric; Njiokou, Flobert; Marsollier, Laurent; Guégan, Jean-François; Pluot-Sigwalt, Dominique; Eyangoh, Sara; Harry, Myriam

    2016-01-01

    Aquatic and semi-aquatic bugs (Heteroptera) represent a remarkable diversity and a resurging interest has been given to documenting at the species level these insects inhabiting Cameroon in Central Africa due to their potential implication in the transmission of the bacterium Mycobacterium ulcerans, the causal agent of Buruli ulcer, an emerging human disease. A survey was carried out over two years in Cameroon. Morphological analyses were done in two steps. A first step consisted in separating the specimens based on broadly shared characters into morphotypes. The specimens were then separated into two independent batches containing each the same representation of each morphotype. One batch (309 specimens) was used by taxonomy experts on aquatic bugs for species level identification and/or to reconcile nymph with their corresponding adult species. The second batch (188 specimens) was used to define species based on the COI DNA sequences (standard sequence used for "DNA barcoding") and using the Automatic Barcode Gap Discovery (ABGD) method. The first morphological analysis step separated the specimens into 63 different morphotypes (49 adults and 14 nymphs), which were then found to belong to 54 morphological species in the infra-orders Gerromorpha and Nepomorpha based on the species-level morphological identification, and 41-45 putative molecular species according to the gap value retained in the ABGD. Integrating morphology and "DNA barcoding" reconciled all the specimens into 62 aquatic bug species in Cameroon. Generally, we obtained a good congruence between species a priori identified based on morphology from adult morphotypes and molecular putative species. Moreover, molecular identification has allowed the association of 86% of nymphs with adults. This work illustrates the importance of integrative taxonomy.

  14. Molecular Species Delimitation and Morphology of Aquatic and Sub-Aquatic Bugs (Heteroptera) in Cameroon

    PubMed Central

    Le Gall, Philippe; Chen, Ping-Ping; Nieser, Nico; Guilbert, Eric; Njiokou, Flobert; Marsollier, Laurent; Guégan, Jean-François; Pluot-Sigwalt, Dominique; Eyangoh, Sara; Harry, Myriam

    2016-01-01

    Aquatic and semi-aquatic bugs (Heteroptera) represent a remarkable diversity and a resurging interest has been given to documenting at the species level these insects inhabiting Cameroon in Central Africa due to their potential implication in the transmission of the bacterium Mycobacterium ulcerans, the causal agent of Buruli ulcer, an emerging human disease. A survey was carried out over two years in Cameroon. Morphological analyses were done in two steps. A first step consisted in separating the specimens based on broadly shared characters into morphotypes. The specimens were then separated into two independent batches containing each the same representation of each morphotype. One batch (309 specimens) was used by taxonomy experts on aquatic bugs for species level identification and/or to reconcile nymph with their corresponding adult species. The second batch (188 specimens) was used to define species based on the COI DNA sequences (standard sequence used for “DNA barcoding”) and using the Automatic Barcode Gap Discovery (ABGD) method. The first morphological analysis step separated the specimens into 63 different morphotypes (49 adults and 14 nymphs), which were then found to belong to 54 morphological species in the infra-orders Gerromorpha and Nepomorpha based on the species-level morphological identification, and 41–45 putative molecular species according to the gap value retained in the ABGD. Integrating morphology and “DNA barcoding” reconciled all the specimens into 62 aquatic bug species in Cameroon. Generally, we obtained a good congruence between species a priori identified based on morphology from adult morphotypes and molecular putative species. Moreover, molecular identification has allowed the association of 86% of nymphs with adults. This work illustrates the importance of integrative taxonomy. PMID:27149077

  15. Comprehensive cooling water study annual report. Volume VIII: semi-aquatic vertebrates, Savannah River Plant

    SciTech Connect

    Gladden, J.B.; Lower, M.W.; Mackey, H.E.; Specht, W.L.; Wilde, E.W.

    1985-07-01

    Several semi-aquatic vertebrate species are regularly observed in ''natural'' and ''post-thermal'' environments at SRP. Fewer species are regularly observed in thermally-altered areas. Yellow-bellied slider turtles, however, seem to thrive in areas of mildly elevated temperatures where they exhibit larger female body size than specimens from some ambient temperature areas of the SRP. Yellow-bellied slider turtles are the predominant species of semi-aquatic turtle on the SRP. Research conducted during 1984 was aimed toward examination of the activity levels of these animals, and their movement patterns within and among thermally- and nonthermally-altered wetlands on the SRP. Additional studies conducted on movement patterns of turtles in relation to reproduction examined emigration rates in five species of turtles during years of normal rainfall compared with a year of drought at a Carolina Bay. Studies of body size of slider turtles showed that animals inhabiting thermally-altered areas attain larger sizes than do individuals from ambient areas, presumably because the elevated temperatures allow for longer annual activity and feeding periods. Slider turtles from coastal, and from thermally- and nonthermally-altered inland populations, were examined for relationships between growth and clutch parameters. Slider turtles from an area of radioactive contamination were also studied for a determination of strontium-90 and cesium-137 bio-elimination. Studies of the brown water snake in the vicinity of Steel Creek and in the vicinity of Upper Three Runs Creek showed that these animals are primarily diurnal and prefer cool water temperatures. Preliminary sampling was initiated in 1984 to determine the structure of the Steel Creek snake community. 65 refs., 5 figs., 26 tabs.

  16. Mapping the Distribution and Biomass of Emergent Aquatic Plants in the Sacramento-San Joaquin River Delta of California Using Landsat Imagery Analysis

    NASA Technical Reports Server (NTRS)

    Potter, Christopher

    2015-01-01

    This study evaluated the cost-effective and timely use of Landsat imagery to map and monitor emergent aquatic plant biomass and to filter satellite image products for the most probable locations of water hyacinth coverage in the Delta based on field observations collected immediately after satellite image acquisition.

  17. Proceedings of the Annual Meeting, Aquatic Plant Control Research Program (25th) Held in Orlando, Florida on 26-30 November 1990

    DTIC Science & Technology

    1991-06-01

    Myriophyllum spicatum in a eutrophic aquatic plant survey. Lake George Park Wisconsin lake. Can. . Bot. 58:527-535. Commision Final Report. New York... New England , a number of lakes were visited in 1990. Qualitative surveys Ten lakes were surveyed in western Mas- were made of watermilfoil (or...176 The Potential for Biological Control of Eurasian Watermilfoil ( Myriophyllum spicatum): Brownington Pond, Vermont

  18. Accumulation of microcystin congeners in different aquatic plants and crops--a case study from lake Amatitlán, Guatemala.

    PubMed

    Romero-Oliva, Claudia Suseth; Contardo-Jara, Valeska; Block, Tobias; Pflugmacher, Stephan

    2014-04-01

    Microcystins (MCs) fate in natural environments can lead to its transfer into aquatic organisms, e.g. aquatic plants. Moreover, lakes in several countries sustain agriculture activities posing a serious health threat for the public. The case of Lake Amatitlán in Guatemala, was addressed to better understand MCs accumulation of four aquatic plants (Polygonum portoricensis, Eichhornia crassipes, Typha sp. and Hydrilla verticillata) coexisting with Microcystis aeruginosa blooms. These findings were further corroborated with an uptake/accumulation laboratory study. Finally crop products (Solanum lycopersicum and Capsicum annuum) irrigated with lake water were also evaluated for MCs. The obtained results suggest that Lake Amatitlán is highly contaminated with MCs (intra- and extracellular 1931 and 90 µg/L, respectively). In fruits of S. lycopersicum and C. annuum a concentration of 1.16 and 1.03 µg/kg dry weight (DW), respectively could be detected. All four aquatic plants showed a high MCs uptake capacity based on obtained bioconcentration factors (BCF) 165, 18, 16 and 11, respectively. These results were further corroborated in a laboratory study with 30 percent of total MCs taken up by H. verticillata within just 7 days. Additionally it was evidenced that all plants accumulated more MC-LR than other MCs congeners. Monitoring of crop products irrigated with lake water needs further consideration.

  19. Phytoremediation: role of terrestrial plants and aquatic macrophytes in the remediation of radionuclides and heavy metal contaminated soil and water.

    PubMed

    Sharma, Sunita; Singh, Bikram; Manchanda, V K

    2015-01-01

    significantly raised the amount of heavy metals and radionuclides in it. Also, these activities are continuously increasing the area of the contaminated sites. In this context, an attempt has been made to review different modes of the phytoremediation and various terrestrial and aquatic plants which are being used to remediate the heavy metals and radionuclide-contaminated soil and aquatic systems. Natural and synthetic enhancers, those hasten the process of metal adsorption/absorption by plants, are also discussed. The article includes 216 references.

  20. Aquatic and terrestrial plant species with potential to remove heavy metals from storm-water.

    PubMed

    Fritioff, Asa; Greger, Maria

    2003-01-01

    Remediation of storm-water polluted with heavy metals should be possible in percolation systems, ponds, or wetlands. The aim of this work was to find plant species for such systems that are efficient in the uptake of Zn, Cu, Cd, and Pb. Plants were collected from percolation and wetland areas and analyzed for heavy metal concentrations. Results showed that submersed and free-floating plants had the capacity to take up high levels of Cu, Zn, and Pb into their shoots. With roots having a concentration factor above 1, the terrestrial plants show efficient stabilization of Cd and Zn and emergent plants show corresponding stabilisation of Zn. In addition, Potamogeton natans, Alisma plantago-aquatica, and Filipendula ulmaria were used in a controlled experiment. The shoots of P. natans and the roots of A. plantago-aquatica were found to accumulate even higher concentrations of Zn, Cu, and Pb than found in the field-harvested plants. Similar results were found for Cd in shoots and Pb in roots of F. ulmaria. Our conclusion is that submersed plant species seem to be the most efficient for removal of heavy metals from storm-water.

  1. Characterization of rough and smooth morphotypes of Mycobacterium abscessus isolates from clinical specimens.

    PubMed

    Rüger, Kai; Hampel, Annegret; Billig, Sandra; Rücker, Nadine; Suerbaum, Sebastian; Bange, Franz-Christoph

    2014-01-01

    Mycobacterium abscessus, which consists of the two subspecies M. abscessus subspecies abscessus and M. abscessus subspecies bolletii, can produce rough or smooth colony morphologies. Here we analyzed 50 M. abscessus isolates cultured from the respiratory specimens of 34 patients, 28 (82%) of whom had cystic fibrosis (CF), with respect to their colony morphologies and antibiotic susceptibilities. The overall proportions of occurrences of the two morphotypes were similar, with specimens from 50% of the patients showing a rough and 38% showing a smooth morphotype. A total of 12% of the specimens from the patients showed both morphotypes simultaneously. At the subspecies level, the proportions of rough and smooth morphotypes differed substantially; 88% of rough morphotypes belonged to M. abscessus subspecies abscessus, and 85% of smooth morphotypes belonged M. abscessus subspecies bolletii. Inducible clarithromycin resistance due to the Erm(41) methylase, as well as high-level resistance to clarithromycin due to mutations within the rrl gene, occurred independently of the morphotype. The MIC50s of amikacin and cefoxitin were identical for the two morphotypes, whereas the MIC50s of tigecycline were 0.25 μg/ml for the rough morphotype and 2.0 μg/ml for the smooth morphotype. Our results show that the smooth morphotype was more dominant in respiratory specimens from CF patients than previously thought. With respect to resistance, colony morphology did not affect the susceptibility of Mycobacterium abscessus to the first-line antibiotics clarithromycin, amikacin, and cefoxitin.

  2. Characterization of Rough and Smooth Morphotypes of Mycobacterium abscessus Isolates from Clinical Specimens

    PubMed Central

    Rüger, Kai; Hampel, Annegret; Billig, Sandra; Rücker, Nadine; Suerbaum, Sebastian

    2014-01-01

    Mycobacterium abscessus, which consists of the two subspecies M. abscessus subspecies abscessus and M. abscessus subspecies bolletii, can produce rough or smooth colony morphologies. Here we analyzed 50 M. abscessus isolates cultured from the respiratory specimens of 34 patients, 28 (82%) of whom had cystic fibrosis (CF), with respect to their colony morphologies and antibiotic susceptibilities. The overall proportions of occurrences of the two morphotypes were similar, with specimens from 50% of the patients showing a rough and 38% showing a smooth morphotype. A total of 12% of the specimens from the patients showed both morphotypes simultaneously. At the subspecies level, the proportions of rough and smooth morphotypes differed substantially; 88% of rough morphotypes belonged to M. abscessus subspecies abscessus, and 85% of smooth morphotypes belonged M. abscessus subspecies bolletii. Inducible clarithromycin resistance due to the Erm(41) methylase, as well as high-level resistance to clarithromycin due to mutations within the rrl gene, occurred independently of the morphotype. The MIC50s of amikacin and cefoxitin were identical for the two morphotypes, whereas the MIC50s of tigecycline were 0.25 μg/ml for the rough morphotype and 2.0 μg/ml for the smooth morphotype. Our results show that the smooth morphotype was more dominant in respiratory specimens from CF patients than previously thought. With respect to resistance, colony morphology did not affect the susceptibility of Mycobacterium abscessus to the first-line antibiotics clarithromycin, amikacin, and cefoxitin. PMID:24197890

  3. Genome-wide analysis of coordinated transcript abundance during seed development in different Brassica rapa morphotypes.

    PubMed

    Basnet, Ram Kumar; Moreno-Pachon, Natalia; Lin, Ke; Bucher, Johan; Visser, Richard G F; Maliepaard, Chris; Bonnema, Guusje

    2013-12-01

    Brassica seeds are important as basic units of plant growth and sources of vegetable oil. Seed development is regulated by many dynamic metabolic processes controlled by complex networks of spatially and temporally expressed genes. We conducted a global microarray gene co-expression analysis by measuring transcript abundance of developing seeds from two diverse B. rapa morphotypes: a pak choi (leafy-type) and a yellow sarson (oil-type), and two of their doubled haploid (DH) progenies, (1) to study the timing of metabolic processes in developing seeds, (2) to explore the major transcriptional differences in developing seeds of the two morphotypes, and (3) to identify the optimum stage for a genetical genomics study in B. rapa seed. Seed developmental stages were similar in developing seeds of pak choi and yellow sarson of B. rapa; however, the colour of embryo and seed coat differed among these two morphotypes. In this study, most transcriptional changes occurred between 25 and 35 DAP, which shows that the timing of seed developmental processes in B. rapa is at later developmental stages than in the related species B. napus. Using a Weighted Gene Co-expression Network Analysis (WGCNA), we identified 47 "gene modules", of which 27 showed a significant association with temporal and/or genotypic variation. An additional hierarchical cluster analysis identified broad spectra of gene expression patterns during seed development. The predominant variation in gene expression was according to developmental stages rather than morphotype differences. Since lipids are the major storage compounds of Brassica seeds, we investigated in more detail the regulation of lipid metabolism. Four co-regulated gene clusters were identified with 17 putative cis-regulatory elements predicted in their 1000 bp upstream region, either specific or common to different lipid metabolic pathways. This is the first study of genome-wide profiling of transcript abundance during seed development in B

  4. Evaluation of aquatic plants for removing polar microcontaminants: a microcosm experiment.

    PubMed

    Matamoros, Víctor; Nguyen, Loc Xuan; Arias, Carlos A; Salvadó, Victòria; Brix, Hans

    2012-08-01

    Microcosm wetland systems (5 L containers) planted with Salvinia molesta, Lemna minor, Ceratophyllum demersum, and Elodea canadensis were investigated for the removal of diclofenac, triclosan, naproxen, ibuprofen, caffeine, clofibric acid and MCPA. After 38 days of incubation, 40-99% of triclosan, diclofenac, and naproxen were removed from the planted and unplanted reactors. In covered control reactors no removal was observed. Caffeine and ibuprofen were removed from 40% to 80% in planted reactors whereas removals in control reactors were much lower (2-30%). Removal of clofibric acid and MCPA were negligible in both planted and unplanted reactors. The findings suggested that triclosan, diclofenac, and naproxen were removed predominantly by photodegradation, whereas caffeine and naproxen were removed by biodegradation and/or plant uptake. Pseudo-first-order removal rate constants estimated from nonlinear regressions of time series concentration data were used to describe the contaminant removals. Removal rate constants ranged from 0.003 to 0.299 d(-1), with half-lives from 2 to 248 days. The formation of two major degradation products from ibuprofen, carboxy-ibuprofen and hydroxy-ibuprofen, and a photodegradation product from diclofenac, 1-(8-Chlorocarbazolyl)acetic acid, were followed as a function of time. This study emphasizes that plants contribute to the elimination capacity of microcontaminants in wetlands systems through biodegradation and uptake processes.

  5. Plant carbohydrate scavenging through tonB-dependent receptors: a feature shared by phytopathogenic and aquatic bacteria.

    PubMed

    Blanvillain, Servane; Meyer, Damien; Boulanger, Alice; Lautier, Martine; Guynet, Catherine; Denancé, Nicolas; Vasse, Jacques; Lauber, Emmanuelle; Arlat, Matthieu

    2007-02-21

    TonB-dependent receptors (TBDRs) are outer membrane proteins mainly known for the active transport of iron siderophore complexes in Gram-negative bacteria. Analysis of the genome of the phytopathogenic bacterium Xanthomonas campestris pv. campestris (Xcc), predicts 72 TBDRs. Such an overrepresentation is common in Xanthomonas species but is limited to only a small number of bacteria. Here, we show that one Xcc TBDR transports sucrose with a very high affinity, suggesting that it might be a sucrose scavenger. This TBDR acts with an inner membrane transporter, an amylosucrase and a regulator to utilize sucrose, thus defining a new type of carbohydrate utilization locus, named CUT locus, involving a TBDR for the transport of substrate across the outer membrane. This sucrose CUT locus is required for full pathogenicity on Arabidopsis, showing its importance for the adaptation to host plants. A systematic analysis of Xcc TBDR genes and a genome context survey suggested that several Xcc TBDRs belong to other CUT loci involved in the utilization of various plant carbohydrates. Interestingly, several Xcc TBDRs and CUT loci are conserved in aquatic bacteria such as Caulobacter crescentus, Colwellia psychrerythraea, Saccharophagus degradans, Shewanella spp., Sphingomonas spp. or Pseudoalteromonas spp., which share the ability to degrade a wide variety of complex carbohydrates and display TBDR overrepresentation. We therefore propose that TBDR overrepresentation and the presence of CUT loci designate the ability to scavenge carbohydrates. Thus CUT loci, which seem to participate to the adaptation of phytopathogenic bacteria to their host plants, might also play a very important role in the biogeochemical cycling of plant-derived nutrients in marine environments. Moreover, the TBDRs and CUT loci identified in this study are clearly different from those characterized in the human gut symbiont Bacteroides thetaiotaomicron, which allow glycan foraging, suggesting a convergent

  6. Plant Carbohydrate Scavenging through TonB-Dependent Receptors: A Feature Shared by Phytopathogenic and Aquatic Bacteria

    PubMed Central

    Boulanger, Alice; Lautier, Martine; Guynet, Catherine; Denancé, Nicolas; Vasse, Jacques

    2007-01-01

    TonB-dependent receptors (TBDRs) are outer membrane proteins mainly known for the active transport of iron siderophore complexes in Gram-negative bacteria. Analysis of the genome of the phytopathogenic bacterium Xanthomonas campestris pv. campestris (Xcc), predicts 72 TBDRs. Such an overrepresentation is common in Xanthomonas species but is limited to only a small number of bacteria. Here, we show that one Xcc TBDR transports sucrose with a very high affinity, suggesting that it might be a sucrose scavenger. This TBDR acts with an inner membrane transporter, an amylosucrase and a regulator to utilize sucrose, thus defining a new type of carbohydrate utilization locus, named CUT locus, involving a TBDR for the transport of substrate across the outer membrane. This sucrose CUT locus is required for full pathogenicity on Arabidopsis, showing its importance for the adaptation to host plants. A systematic analysis of Xcc TBDR genes and a genome context survey suggested that several Xcc TBDRs belong to other CUT loci involved in the utilization of various plant carbohydrates. Interestingly, several Xcc TBDRs and CUT loci are conserved in aquatic bacteria such as Caulobacter crescentus, Colwellia psychrerythraea, Saccharophagus degradans, Shewanella spp., Sphingomonas spp. or Pseudoalteromonas spp., which share the ability to degrade a wide variety of complex carbohydrates and display TBDR overrepresentation. We therefore propose that TBDR overrepresentation and the presence of CUT loci designate the ability to scavenge carbohydrates. Thus CUT loci, which seem to participate to the adaptation of phytopathogenic bacteria to their host plants, might also play a very important role in the biogeochemical cycling of plant-derived nutrients in marine environments. Moreover, the TBDRs and CUT loci identified in this study are clearly different from those characterized in the human gut symbiont Bacteroides thetaiotaomicron, which allow glycan foraging, suggesting a convergent

  7. Chain-Length Distribution and Hydrogen Isotopic Fraction of n-alkyl Lipids in Aquatic and Terrestrial Plants: Implications for Paleoclimate Reconstructions

    NASA Astrophysics Data System (ADS)

    Gao, L.; Littlejohn, S.; Hou, J.; Toney, J.; Huang, Y.

    2008-12-01

    Recent studies demonstrate that in lacustrine sediments, aquatic plant lipids (e.g., C22-fatty acid) record lake water D/H ratio variation, while long-chain fatty acids (C26-C32, major components of terrestrial plant leaf waxes), record D/H ratios of precipitation (especially in arid regions). However, there are insufficient literature data for the distribution and hydrogen isotopic fractionation of n-alkyl lipids in aquatic and terrestrial plants. In this study, we determined the chain-length distributions and D/H ratios of n-alkyl lipids from 17 aquatic plant species (9 emergent, 4 floating and 4 submerge species) and 13 terrestrial plant species (7 grasses and 6 trees) from Blood Pond, Massachusetts. Our results are consistent with previous studies and provide a solid basis for the paleoclimatic reconstruction using D/H ratios of aquatic and terrestrial plant biomarkers. In addition, systematic hydrogen isotopic analyses on leaf waxes, leaf, stem and soil waters from trees and grasses significantly advance our understanding of our previously observed large D/H ratio difference between tree and grass leaf waxes. Our data indicate that the observed difference is not due to differences in leaf water D/H ratios. In comparison with grasses, trees use greater proportion of D-enriched residual or stored carbohydrates (as opposed to current photosynthetic carbohydrates) for leaf wax biosynthesis, resulting in higher leaf wax D/H ratios. The residual carbohydrates are enriched in deuterium because of the preferential consumption of light-hydrogen substrates during plant metabolism.

  8. Does Waterborne Exposure Explain Effects Caused by Neonicotinoid-Contaminated Plant Material in Aquatic Systems?

    PubMed

    Englert, Dominic; Zubrod, Jochen P; Link, Moritz; Mertins, Saskia; Schulz, Ralf; Bundschuh, Mirco

    2017-05-16

    Neonicotinoids are increasingly applied on trees as protection measure against insect pests. Consequently, neonicotinoids are inevitably transferred into aquatic environments either via spray drift or surface runoff or (due to neonicotinoids' systemic nature) via senescent leaves. There particularly leaf-shredding invertebrates may be exposed to neonicotinoids through both the water phase and the consumption of contaminated leaves. In 7 day bioassays (n = 30), we examined ecotoxicological differences between these two exposure scenarios for an amphipod and an insect nymph with their feeding rate as the response variable. Organisms either experienced waterborne neonicotinoid (i.e., imidacloprid, thiacloprid, and acetamiprid) exposure only or a combined exposure (waterborne and dietary) through both the consumption of contaminated leaves and neonicotinoids leaching from leaves into water. The amphipod (7 day EC50s from 0.3 to 8.4 μg/L) was more sensitive than the insect nymph (7 day EC50s from 7.0 to 19.4 μg/L). Moreover, for both species, concentration-response models derived from water concentrations indicated higher effects under the combined exposure. Together with the observed inability of shredders to avoid neonicotinoid-contaminated leaves, our results emphasize the relevance of dietary exposure (e.g., via leaves) for systemic insecticides. Thus, it would be prudent to consider dietary exposure during the registration of systemic insecticides to safeguard ecosystem integrity.

  9. Aquatic plants stimulate the growth of and biofilm formation by Mycobacterium ulcerans in axenic culture and harbor these bacteria in the environment.

    PubMed

    Marsollier, Laurent; Stinear, Timothy; Aubry, Jacques; Saint André, Jean Paul; Robert, Raymond; Legras, Pierre; Manceau, Anne-Lise; Audrain, Christine; Bourdon, Sandra; Kouakou, Henri; Carbonnelle, Bernard

    2004-02-01

    Mycobacterium ulcerans is the causative agent of Buruli ulcer, one of the most common mycobacterial diseases of humans. Recent studies have implicated aquatic insects in the transmission of this pathogen, but the contributions of other elements of the environment remain largely unknown. We report here that crude extracts from two green algae added to the BACTEC 7H12B culture medium halved the doubling time of M. ulcerans and promoted biofilm formation. Using the 7H12B medium, modified by the addition of the algal extract, and immunomagnetic separation, we also demonstrate that M. ulcerans is associated with aquatic plants in an area of the Ivory Coast where Buruli ulcer is endemic. Genotype analysis showed that plant-associated M. ulcerans had the same profile as isolates recovered in the same region from both aquatic insects and clinical specimens. These observations implicate aquatic plants as a reservoir of M. ulcerans and add a new potential link in the chain of transmission of M. ulcerans to humans.

  10. Aquatic Plants Stimulate the Growth of and Biofilm Formation by Mycobacterium ulcerans in Axenic Culture and Harbor These Bacteria in the Environment

    PubMed Central

    Marsollier, Laurent; Stinear, Timothy; Aubry, Jacques; Saint André, Jean Paul; Robert, Raymond; Legras, Pierre; Manceau, Anne-Lise; Audrain, Christine; Bourdon, Sandra; Kouakou, Henri; Carbonnelle, Bernard

    2004-01-01

    Mycobacterium ulcerans is the causative agent of Buruli ulcer, one of the most common mycobacterial diseases of humans. Recent studies have implicated aquatic insects in the transmission of this pathogen, but the contributions of other elements of the environment remain largely unknown. We report here that crude extracts from two green algae added to the BACTEC 7H12B culture medium halved the doubling time of M. ulcerans and promoted biofilm formation. Using the 7H12B medium, modified by the addition of the algal extract, and immunomagnetic separation, we also demonstrate that M. ulcerans is associated with aquatic plants in an area of the Ivory Coast where Buruli ulcer is endemic. Genotype analysis showed that plant-associated M. ulcerans had the same profile as isolates recovered in the same region from both aquatic insects and clinical specimens. These observations implicate aquatic plants as a reservoir of M. ulcerans and add a new potential link in the chain of transmission of M. ulcerans to humans. PMID:14766593

  11. Complex inter-Kingdom interactions: carnivorous plants affect growth of an aquatic vertebrate.

    PubMed

    Davenport, Jon M; Riley, Alex W

    2017-05-01

    Coexistence of organisms in nature is more likely when phenotypic similarities of individuals are reduced. Despite the lack of similarity, distantly related taxa still compete intensely for shared resources. No larger difference between organisms that share a common prey could exist than between carnivorous plants and animals. However, few studies have considered inter-Kingdom competition among carnivorous plants and animals. In order to evaluate interactions between a carnivorous plant (greater bladderwort, Utricularia vulgaris) and a vertebrate (bluegill, Lepomis macrochirus) on a shared prey (zooplankton), we conducted a mesocosm experiment. We deployed two levels of bladderwort presence (functional and crushed) and measured bluegill responses (survival and growth). Zooplankton abundance was reduced the greatest in bluegill and functional bladderwort treatments. Bluegill survival did not differ among treatments, but growth was greatest with crushed bladderwort. Thus, bluegill growth was facilitated by reducing interference competition in the presence of crushed bladderwort. The facilitating effect was dampened, however, when functional bladderwort removed a shared prey. To our knowledge, this is one of the first studies to experimentally demonstrate interactions between a carnivorous plant and a fish. Our data suggest that carnivorous plants may actively promote or reduce animal co-occurrence from some ecosystems via facilitation or competition.

  12. Uptake and translocation of non-ionised pesticides in the emergent aquatic plant parrot feather Myriophyllum aquaticum.

    PubMed

    de Carvalho, Renato F; Bromilow, Richard H; Greenwood, Richard

    2007-08-01

    The uptake of four (14)C-labelled non-ionised compounds, the methyl carbamoyloxime insecticide/nematicide oxamyl and three model phenylureas, from solution by rooted stems of the aquatic plant parrot feather [Myriophyllum aquaticum (Vell.) Verdc], together with translocation to the emergent shoots, was measured over periods of 24 and 48 h. Uptake into the submerged tissues of roots and stem base could be ascribed to two processes: movement into the aqueous phase of cells and then partitioning onto the plant solids. This latter process was related to lipophilicity (as measured by the l-octanol/water partition coefficient, K(ow)) and gave rise to high uptake rates of the most lipophilic compounds. Translocation to shoots was passive and was optimal at log K(ow) approximately 1.8, at which the efficiency of translocation of compound was about 40% of that of water. This optimum log K(ow) was identical to that observed previously in barley, although the translocation efficiency was somewhat less in parrot feather. Solvation parameters were applied to model uptake and translocation of a set of ten compounds by barley with the particular objective of understanding why translocation efficiency is lower at log K(ow) > 1.8. Copyright (c) 2007 Society of Chemical Industry

  13. Resting electrical network activity in traps of the aquatic carnivorous plants of the genera Aldrovanda and Utricularia.

    PubMed

    Masi, Elisa; Ciszak, Marzena; Colzi, Ilaria; Adamec, Lubomir; Mancuso, Stefano

    2016-04-27

    In this study the MEA (multielectrode array) system was used to record electrical responses of intact and halved traps, and other trap-free tissues of two aquatic carnivorous plants, Aldrovanda vesiculosa and Utricularia reflexa. They exhibit rapid trap movements and their traps contain numerous glands. Spontaneous generation of spikes with quite uniform shape, propagating across the recording area, has been observed for all types of sample. In the analysis of the electrical network, higher richer synchronous activity was observed relative to other plant species and organs previously described in the literature: indeed, the time intervals between the synchronized clusters (the inter-spike intervals) create organized patterns and the propagation times vary non-linearly with the distance due to this synchronization. Interestingly, more complex electrical activity was found in traps than in trap-free organs, supporting the hypothesis that the nature of the electrical activity may reflect the anatomical and functional complexity of different organs. Finally, the electrical activity of functionally different traps of Aldrovanda (snapping traps) and Utricularia (suction traps) was compared and some differences in the features of signal propagation were found. According to these results, a possible use of the MEA system for the study of different trap closure mechanisms is proposed.

  14. Resting electrical network activity in traps of the aquatic carnivorous plants of the genera Aldrovanda and Utricularia

    PubMed Central

    Masi, Elisa; Ciszak, Marzena; Colzi, Ilaria; Adamec, Lubomir; Mancuso, Stefano

    2016-01-01

    In this study the MEA (multielectrode array) system was used to record electrical responses of intact and halved traps, and other trap-free tissues of two aquatic carnivorous plants, Aldrovanda vesiculosa and Utricularia reflexa. They exhibit rapid trap movements and their traps contain numerous glands. Spontaneous generation of spikes with quite uniform shape, propagating across the recording area, has been observed for all types of sample. In the analysis of the electrical network, higher richer synchronous activity was observed relative to other plant species and organs previously described in the literature: indeed, the time intervals between the synchronized clusters (the inter-spike intervals) create organized patterns and the propagation times vary non-linearly with the distance due to this synchronization. Interestingly, more complex electrical activity was found in traps than in trap-free organs, supporting the hypothesis that the nature of the electrical activity may reflect the anatomical and functional complexity of different organs. Finally, the electrical activity of functionally different traps of Aldrovanda (snapping traps) and Utricularia (suction traps) was compared and some differences in the features of signal propagation were found. According to these results, a possible use of the MEA system for the study of different trap closure mechanisms is proposed. PMID:27117956

  15. Chromosomal abnormalities in roots of aquatic plant Elodea canadensis as a tool for testing genotoxicity of bottom sediments.

    PubMed

    Zotina, Tatiana; Medvedeva, Marina; Trofimova, Elena; Alexandrova, Yuliyana; Dementyev, Dmitry; Bolsunovsky, Alexander

    2015-12-01

    Submersed freshwater macrophytes are considered as relevant indicators for use in bulk bottom sediment contact tests. The purpose of this study was to estimate the validity of endpoints of aquatic plant Elodea canadensis for laboratory genotoxicity testing of natural bottom sediments. The inherent level of chromosome abnormalities (on artificial sediments) in roots of E. canadensis under laboratory conditions was lower than the percentage of abnormal cells in bulk sediments from the Yenisei River. The percentage of abnormal cells in roots of E. canadensis was more sensitive to the presence of genotoxic agents in laboratory contact tests than in the natural population of the plant. The spectra of chromosomal abnormalities that occur in roots of E. canadensis under natural conditions in the Yenisei River and in laboratory contact tests on the bulk bottom sediments from the Yenisei River were similar. Hence, chromosome abnormalities in roots of E. canadensis can be used as a relevant and sensitive genotoxicity endpoint in bottom sediment-contact tests. Copyright © 2015 Elsevier Inc. All rights reserved.

  16. Effect of Hirschmanniella caudacrena on the Submersed Aquatic Plants Ceratophyllum demersum and Hydrilla verticillata

    PubMed Central

    Gerber, Karin; Smart, Grover C.

    1987-01-01

    In vitro pathogenicity tests demonstrated that Hirschmanniella caudacrena is pathogenic to Ceratophyllum demersum (coontail). Symptoms were chlorotic tissue, deformed stems, and, finally, death of the plant. Inoculum densities of 500 nematodes per 5-cm-long cutting in a test tube containing 50 ml of water resulted in death and decay of some of the cuttings within 8 weeks; 100 nematodes killed the plants in 12 weeks, and 50 and 25 nematodes killed them in 16 weeks. The lowest inoculum level of 10 nematodes did not seriously affect the plants at 16 weeks when the experiment was terminated. A second test conducted outdoors in glass jars containing 3 liters of water and two cuttings weighing a total of 15 g fresh weight showed damage, but results were not statistically significant. Hydrilla verticillata inoculated with H. caudacrena was not affected seriously. PMID:19290169

  17. Morphotypes of the quartz basic rhombohedra and crystallization conditions

    NASA Astrophysics Data System (ADS)

    Rakin, V. I.

    2017-07-01

    An analysis of the combinatorial-morphological types of faceting for a quartz crystal head has provided 23 types of combinations of faces of basic positive and negative quartz rhombohedra, among which three full-face morphotypes are generally observed under natural conditions. The theoretical occurrence rates are obtained for these morphotypes under isotropic growth conditions, and a morphological analysis is performed over seven samples of natural quartz crystals. A method is proposed for estimating some most important parameters of the crystal formation system: the ratio of variation in the central distances to the faces of crystal rhombohedra, which is related to its growth rates; the ratios of the intermediate growth rates of the rhombohedra and prism, the index of infection with Dauphiné twins, and the feed dissymmetry factor.

  18. Do varying aquatic plant species affect phytoplankton and crustacean responses to a nitrogen-permethrin mixture?

    USDA-ARS?s Scientific Manuscript database

    Hydraulically connected wetland microcosms vegetated with either Typha latifolia or Myriophyllum aquaticum were amended with an NH4NO3 and permethrin mixture to assess the effectiveness of both plant species in mitigating ecological effects of the pollutant mixture on phytoplankton (as chlorophyll a...

  19. Subtle temperature differences may well determine who wins: a story of three submerged aquatic plant species

    USDA-ARS?s Scientific Manuscript database

    As temperatures increases globally, shifts in the distribution of plant species are expected, with unknown effects on invasive species abundance. It is then of value to understand the role increased temperature may have on invasive species. Although nonhomeothermic organisms are the mercy of environ...

  20. Mechanical Harvesting of Aquatic Plants. Report 2. Evaluation of Selected Handling Functions of Mechanical Control.

    DTIC Science & Technology

    1980-06-01

    specifications that did not include these considerations by the Aquamarine Corporation, 26 If a. Pusher rake in the travel position b. Pushing rake with plants...was the Aquamarine Model No. W-455, and the land-based conveyor was Little Giant Model M-21, manufactured by the Portable Elevator Division, Dynamics

  1. Designing and using phenological studies to define management strategies for aquatic plants

    USDA-ARS?s Scientific Manuscript database

    Scientists and managers alike have recognized that weed management activities in the past were timed more for the convenience of the applicator or response of the resource manager than in consideration of the biology of the target plant. A thorough understanding of the life history and phenology of...

  2. Bacterial communities associated with culex mosquito larvae and two emergent aquatic plants of bioremediation importance.

    PubMed

    Duguma, Dagne; Rugman-Jones, Paul; Kaufman, Michael G; Hall, Michael W; Neufeld, Josh D; Stouthamer, Richard; Walton, William E

    2013-01-01

    Microbes are important for mosquito nutrition, growth, reproduction and control. In this study, we examined bacterial communities associated with larval mosquitoes and their habitats. Specifically, we characterized bacterial communities associated with late larval instars of the western encephalitis mosquito (Culextarsalis), the submerged portions of two emergent macrophytes (California bulrush, Schoenoplectuscalifornicus and alkali bulrush, Schoenoplectusmaritimus), and the associated water columns to investigate potential differential use of resources by mosquitoes in different wetland habitats. Using next-generation sequence data from 16S rRNA gene hypervariable regions, the alpha diversity of mosquito gut microbial communities did not differ between pond mesocosms containing distinct monotypic plants. Proteobacteria, dominated by the genus Thorsellia (Enterobacteriaceae), was the most abundant phylum recovered from C. tarsalis larvae. Approximately 49% of bacterial OTUs found in larval mosquitoes were identical to OTUs recovered from the water column and submerged portions of the two bulrushes. Plant and water samples were similar to one another, both being dominated by Actinobacteria, Bacteroidetes, Cyanobacteria, Proteobacteria and Verrucomicrobia phyla. Overall, the bacterial communities within C. tarsalis larvae were conserved and did not change across sampling dates and between two distinct plant habitats. Although Thorsellia spp. dominated mosquito gut communities, overlap of mosquito gut, plant and water-column OTUs likely reveal the effects of larval feeding. Future research will investigate the role of the key indicator groups of bacteria across the different developmental stages of this mosquito species.

  3. Mechanical harvesting of aquatic plants. Report 3. Evaluation of the Limnos System

    SciTech Connect

    Smith, J.L.

    1984-05-01

    The Limnos Mechanical Harvesting System consists of a separate cutter machine; a harvester, which includes a gathering and conveyor pickup unit and a processor; and two transport tank barges. System operational tests were conducted on the Withlacoochee River in central Florida during the summer of 1979. Plants harvested were primarily topped-out hydrilla with small amounts of waterhyacinth. Productivity of the cutter unit was evaluated separately and in conjunction with the harvester. Tests were conducted with the harvester with the tank barges to remove the plant material from the water and also without the barges, which allowed the processed plant materials to be discharged directly into the water body. High productivity of the harvester in dense hydrilla (and water-hyacinth mixtures) required reducing the width of cut of the plant material or using 18-ft cuts at two depths (3 and 6 ft). This procedure limited the mass of material that had to be handled by the harvester. Several potential areas requiring additional research were identified as a result of these tests: improved procedures for evaluating mechanical harvesting machines, and possible improvements to the Limnos harvester system to allow higher productivity. 5 figures, 4 tables.

  4. Bacterial Communities Associated with Culex Mosquito Larvae and Two Emergent Aquatic Plants of Bioremediation Importance

    PubMed Central

    Duguma, Dagne; Rugman-Jones, Paul; Kaufman, Michael G.; Hall, Michael W.; Neufeld, Josh D.; Stouthamer, Richard; Walton, William E.

    2013-01-01

    Microbes are important for mosquito nutrition, growth, reproduction and control. In this study, we examined bacterial communities associated with larval mosquitoes and their habitats. Specifically, we characterized bacterial communities associated with late larval instars of the western encephalitis mosquito (Culextarsalis), the submerged portions of two emergent macrophytes (California bulrush, Schoenoplectuscalifornicus and alkali bulrush, Schoenoplectusmaritimus), and the associated water columns to investigate potential differential use of resources by mosquitoes in different wetland habitats. Using next-generation sequence data from 16S rRNA gene hypervariable regions, the alpha diversity of mosquito gut microbial communities did not differ between pond mesocosms containing distinct monotypic plants. Proteobacteria, dominated by the genus Thorsellia (Enterobacteriaceae), was the most abundant phylum recovered from C. tarsalis larvae. Approximately 49% of bacterial OTUs found in larval mosquitoes were identical to OTUs recovered from the water column and submerged portions of the two bulrushes. Plant and water samples were similar to one another, both being dominated by Actinobacteria, Bacteroidetes, Cyanobacteria, Proteobacteria and Verrucomicrobia phyla. Overall, the bacterial communities within C. tarsalis larvae were conserved and did not change across sampling dates and between two distinct plant habitats. Although Thorsellia spp. dominated mosquito gut communities, overlap of mosquito gut, plant and water-column OTUs likely reveal the effects of larval feeding. Future research will investigate the role of the key indicator groups of bacteria across the different developmental stages of this mosquito species. PMID:23967314

  5. Hazard evaluation of soil contaminants with aquatic animals and plant toxicity tests

    SciTech Connect

    Ramanathan, A.; Burks, S.L.

    1996-12-31

    Deleterious effects upon the biota should be one of the principal characteristics used to perform the initial assessment of contamination and the acceptable level of clean-up at hazardous waste sites. Acute toxicity tests are probably the best means for conducting rapid preliminary assessment of distribution and extent of toxic conditions at a site. On the other hand acute toxicity tests may not be adequate indicators of potential effects at critical life stages or responses to longer term exposure to contaminants. Chronic toxicity tests are generally more sensitive than acute tests, and can be used to predict {open_quotes}no effect{close_quotes} or {open_quotes}safe{close_quotes} levels of contamination. In addition, chronic tests provide a better index of field population responses and more closely mimic actual exposure in the field. Partial chronic tests such as the 7 d Ceriodaphnia sp. survival and reproduction test and 7 d fathead minnow survival and growth test are widely used to predict effects upon critical stages in the life cycle of chemical and mixtures. The overall objective of this project was to evaluate the potential hazard of contaminants at an abandoned oil refinery upon aquatic ecosystems within the vicinity. A battery of acute and partial chronic toxicity tests were used to evaluate potential effects of contaminated soil and leachates of soil upon rice seed germination and root growth, Ceriodaphnia acute survival, fathead minnow acute survival, Microtox acute response, 7 d Ceriodaphnia survival and reproduction, and 7 d fathead minnow survival and growth. The specific tests used to accomplish the overall objective included; (1) To estimate phytotoxicity of the soil at the selected contaminated areas within the refinery, (2) to determine potential for leaching at the selected contaminated areas within the refinery, and (3) to assess the relative toxicity of each of the six contaminated areas in the refinery. 13 refs., 3 tabs.

  6. The Effect of Aquatic Plant Abundance on Shell Crushing Resistance in a Freshwater Snail

    PubMed Central

    Chaves-Campos, Johel; Coghill, Lyndon M.; García de León, Francisco J.; Johnson, Steven G.

    2012-01-01

    Most of the shell material in snails is composed of calcium carbonate but the organic shell matrix determines the properties of calcium carbonate crystals. It has been shown that the deposition of calcium carbonate is affected by the ingestion of organic compounds. We hypothesize that organic compounds not synthesized by the snails are important for shell strength and must be obtained from the diet. We tested this idea indirectly by evaluating whether the abundance of the organic matter that snails eat is related to the strength of their shells. We measured shell crushing resistance in the snail Mexipyrgus churinceanus and the abundance of the most common aquatic macrophyte, the water lily Nymphaea ampla, in ten bodies of water in the valley of Cuatro Ciénegas, Mexico. We used stable isotopes to test the assumption that these snails feed on water lily organic matter. We also measured other factors that can affect crushing resistance, such as the density of crushing predators, snail density, water pH, and the concentration of calcium and phosphorus in the water. The isotope analysis suggested that snails assimilate water lily organic matter that is metabolized by sediment bacteria. The variable that best explained the variation in crushing resistance found among sites was the local abundance of water lilies. We propose that the local amount of water lily organic matter provides organic compounds important in shell biomineralization, thus determining crushing resistance. Hence, we propose that a third trophic level could be important in the coevolution of snail defensive traits and predatory structures. PMID:22970206

  7. The effect of aquatic plant abundance on shell crushing resistance in a freshwater snail.

    PubMed

    Chaves-Campos, Johel; Coghill, Lyndon M; García de León, Francisco J; Johnson, Steven G

    2012-01-01

    Most of the shell material in snails is composed of calcium carbonate but the organic shell matrix determines the properties of calcium carbonate crystals. It has been shown that the deposition of calcium carbonate is affected by the ingestion of organic compounds. We hypothesize that organic compounds not synthesized by the snails are important for shell strength and must be obtained from the diet. We tested this idea indirectly by evaluating whether the abundance of the organic matter that snails eat is related to the strength of their shells. We measured shell crushing resistance in the snail Mexipyrgus churinceanus and the abundance of the most common aquatic macrophyte, the water lily Nymphaea ampla, in ten bodies of water in the valley of Cuatro Ciénegas, Mexico. We used stable isotopes to test the assumption that these snails feed on water lily organic matter. We also measured other factors that can affect crushing resistance, such as the density of crushing predators, snail density, water pH, and the concentration of calcium and phosphorus in the water. The isotope analysis suggested that snails assimilate water lily organic matter that is metabolized by sediment bacteria. The variable that best explained the variation in crushing resistance found among sites was the local abundance of water lilies. We propose that the local amount of water lily organic matter provides organic compounds important in shell biomineralization, thus determining crushing resistance. Hence, we propose that a third trophic level could be important in the coevolution of snail defensive traits and predatory structures.

  8. Wave‐induced Hydraulic Forces on Submerged Aquatic Plants in Shallow Lakes

    PubMed Central

    SCHUTTEN, J.; DAINTY, J.; DAVY, A. J.

    2004-01-01

    • Background and Aims Hydraulic pulling forces arising from wave action are likely to limit the presence of freshwater macrophytes in shallow lakes, particularly those with soft sediments. The aim of this study was to develop and test experimentally simple models, based on linear wave theory for deep water, to predict such forces on individual shoots. • Methods Models were derived theoretically from the action of the vertical component of the orbital velocity of the waves on shoot size. Alternative shoot‐size descriptors (plan‐form area or dry mass) and alternative distributions of the shoot material along its length (cylinder or inverted cone) were examined. Models were tested experimentally in a flume that generated sinusoidal waves which lasted 1 s and were up to 0·2 m high. Hydraulic pulling forces were measured on plastic replicas of Elodea sp. and on six species of real plants with varying morphology (Ceratophyllum demersum, Chara intermedia, Elodea canadensis, Myriophyllum spicatum, Potamogeton natans and Potamogeton obtusifolius). • Key Results Measurements on the plastic replicas confirmed predicted relationships between force and wave phase, wave height and plant submergence depth. Predicted and measured forces were linearly related over all combinations of wave height and submergence depth. Measured forces on real plants were linearly related to theoretically derived predictors of the hydraulic forces (integrals of the products of the vertical orbital velocity raised to the power 1·5 and shoot size). • Conclusions The general applicability of the simplified wave equations used was confirmed. Overall, dry mass and plan‐form area performed similarly well as shoot‐size descriptors, as did the conical or cylindrical models of shoot distribution. The utility of the modelling approach in predicting hydraulic pulling forces from relatively simple plant and environmental measurements was validated over a wide range of forces, plant sizes and

  9. Copper, zinc and lead biogeochemistry in aquatic and land plants from the Iberian Pyrite Belt (Portugal) and north of Morocco mining areas.

    PubMed

    Durães, Nuno; Bobos, Iuliu; Ferreira da Silva, Eduardo; Dekayir, Abdelilah

    2015-02-01

    The ability of aquatic (Juncus effusus L., Scirpus holoschoenus L., Thypha latifolia L. and Juncus sp.) and land (Cistus ladanifer L., Erica andevalensis C.-R., Nerium oleander L., Isatis tinctoria L., Rosmarinus officinalis L., Cynodon dactylon L. and Hordeum murinum L.) plants from Portugal (Aljustrel, Lousal and São Domingos) and Morocco (Tighza and Zeida) mining areas to uptake, translocate and tolerate heavy metals (Cu, Zn and Pb) was evaluated. The soils (rhizosphere) of the first mining area are characterized by high acidity conditions (pH 2-5), whereas from the second area, by alkaline conditions (pH 7.0-8.5). Physicochemical parameters and mineralogy of the rhizosphere were determined from both areas. Chemical analysis of plants and the rhizosphere was carried out by inductively coupled plasma emission spectrometry. The sequential chemical extraction procedure was applied for rhizosphere samples collected from both mining areas. In the acid conditions, the aquatic plants show a high capacity for Zn bioaccumulation and translocation and less for Pb, reflecting the following metal mobility sequence: Zn > Cu > Pb. Kaolinite detected in the roots by infrared spectroscopy (IR) contributed to metal fixation (i.e. Cu), reducing its translocation to the aerial parts. Lead identified in the roots of land plants (e.g. E. andevalensis) was probably adsorbed by C-H functional groups identified by IR, being easily translocated to the aerial parts. It was found that aquatic plants are more efficient for phytostabilization than bioaccumulation. Lead is more bioavailable in the rhizosphere from Morocco mining areas due to scarcity of minerals with high adsorption ability, being absorbed and translocated by both aquatic and land plants.

  10. Wastewater treatment plant effluent as a source of microplastics: review of the fate, chemical interactions and potential risks to aquatic organisms.

    PubMed

    Ziajahromi, Shima; Neale, Peta A; Leusch, Frederic D L

    2016-11-01

    Wastewater treatment plant (WWTP) effluent has been identified as a potential source of microplastics in the aquatic environment. Microplastics have recently been detected in wastewater effluent in Western Europe, Russia and the USA. As there are only a handful of studies on microplastics in wastewater, it is difficult to accurately determine the contribution of wastewater effluent as a source of microplastics. However, even the small amounts of microplastics detected in wastewater effluent may be a remarkable source given the large volumes of wastewater treatment effluent discharged to the aquatic environment annually. Further, there is strong evidence that microplastics can interact with wastewater-associated contaminants, which has the potential to transport chemicals to aquatic organisms after exposure to contaminated microplastics. In this review we apply lessons learned from the literature on microplastics in the aquatic environment and knowledge on current wastewater treatment technologies, with the aim of identifying the research gaps in terms of (i) the fate of microplastics in WWTPs, (ii) the potential interaction of wastewater-based microplastics with trace organic contaminants and metals, and (iii) the risk for aquatic organisms.

  11. Colonization dynamics of ciliate morphotypes modified by shifting sandy sediments.

    PubMed

    Risse-Buhl, Ute; Felsmann, Katja; Mutz, Michael

    2014-08-01

    Sandy stream-bed sediments colonized by a diverse ciliate community are subject to various disturbance regimes. In microcosms, we investigated the effect of sediment shifting on the colonization dynamics of 3 ciliate morphotypes differing in morphology, behavior and feeding strategy. The dynamics of the ciliate morphotypes inhabiting sediment pore water and overlying water were observed at 3 sediment shifting frequencies: (1) stable sediments, (2) periodically shifting sediments such as migrating ripples, and (3) continuously shifting sediments as occurring during scour events of the uppermost sediment. Sediment shifting significantly affected the abundance and growth rate of the ciliate morphotypes. The free-swimming filter feeder Dexiostoma campylum was vulnerable to washout by sediment shifting since significantly higher numbers occurred in the overlying water than in pore water. Abundance of D. campylum only increased in pore water of stable sediments. On the contrary, the vagile grasper feeder Chilodonella uncinata and the sessile filter feeder Vorticella convallaria had positive growth rates and successfully colonized sediments that shifted periodically and continuously. Thus, the spatio-temporal pattern of sediment dynamics acts as an essential factor of impact on the structure, distribution and function of ciliate communities in sand-bed streams. Copyright © 2014 Elsevier GmbH. All rights reserved.

  12. Coralligenous morphotypes on subhorizontal substrate: A new categorization

    NASA Astrophysics Data System (ADS)

    Bracchi, Valentina A.; Basso, Daniela; Marchese, Fabio; Corselli, Cesare; Savini, Alessandra

    2017-07-01

    Coralligenous has a relevant role in submarine landscape formation and demise through geological times, producing various morphotypes on the seafloor. Several terms are used to define coralligenous morphotypes, but their application through different geological and environmental settings still remains inconsistent. Through a systematic analysis of seafloor acoustic remote data (multibeam, side scan sonar and subbottom profiler) along Apulia continental shelf, ground-truthed by video observations and direct sampling, we detected a number of coralligenous morpho-acoustic facies as 0.2 up to 4 m topographic reliefs with steep flanks and a rigid inhomogeneous biogenic framework, characterized by medium to strong SSS backscatter and a variable plan-view geometry. The observed pattern led to the identification of coralligenous meso- and macrohabitat in which the biogenic frameworks (i.e. coralligenous) prevail as sole biocommunity on the seafloor or are associated with other type of habitats: (i) coralligenous sensu stricto, (ii) coralligenous and detritic bottom, (iii) coralligenous and muddy bottom, (iv) coralligenous and Posidonia meadow. Finally we improve the geomorphological definition of bank, proposing this new descriptive rigorous categorization for coralligenous morphotypes on sub-horizontal substrate: 1) tabular bank, 2) discrete relief, and 3) hybrid bank.

  13. Does the effect of herbicide pulse exposure on aquatic plants depend on Kow or mode of action?

    PubMed

    Cedergreen, Nina; Andersen, Lone; Olesen, Charlotte Frihauge; Spliid, Hans Henrik; Streibig, Jens Carl

    2005-02-10

    The highest concentrations of herbicides measured in flowing surface waters are often only present for short periods of time. These herbicide pulses can reach concentrations that would affect aquatic plants if present over a long time. The aim of this study was to assess the effect of a 3-h herbicide pulse relative to the effects of long-term (4 and 7 days) exposure of six herbicides with different sites of action and different K(ow) on the growth of the floating macrophyte Lemna minor. The herbicides were the two photosynthetic inhibitors: diquat and terbuthylazine, the inhibitors of acetolactate syntase (ALS), imazamox and metsulfuron-methyl and the microtubule assembly inhibitors propyzamide and pendimethalin. The log K(ow) ranged from -4.6 to 5.2. For imazamox, metsulfuron-methyl, propyzamide and pendimethalin a 3-h pulse induced the effect on area-specific growth as did a 4-day exposure at an approximate 10-fold higher concentration. For diquat and terbuthylazine a concentration closer to a factor of 100 or more was needed for a 3-h pulse to induce an effect similar to that of a 4-day exposure. For diquat, the low pulse-effect was most likely due to a slow uptake of the hydrophilic ion (log K(ow) = -4.6), as no effect was observed on chlorophyll fluorescence within 8 h after exposure. The chlorophyll fluorescence parameters are expected to respond quickly to a PSI inhibitor as diquat. For terbuthylazine, fluorescence measurements showed an effect on photosynthesis within 1h of exposure, and reached a minimum after 3 h. Recovery was fast, and initial fluorescence was restored within 24 h. Hence, the small pulse effect on area-specific growth was due to rapid recovery of photosynthesis. In contrast to terbuthylazine, the stop in area-specific growth observed for the ALS-and microtubule assembly inhibitors, took up to 4 days to recover from. Such a long recovery time after a pulse of only 3 h indicate that at realistic pulse exposures of up to a day or two, pulse

  14. Physicochemical Characteristics and Composition of Three Morphotypes of Cyperus esculentus Tubers and Tuber Oils

    PubMed Central

    Bado, Souleymane; Bazongo, Patrice; Son, Gouyahali; Kyaw, Moe Thida; Forster, Brian Peter; Nielen, Stephan; Lykke, Anne Mette; Ouédraogo, Amadé; Bassolé, Imaël Henri Nestor

    2015-01-01

    Tuber characteristics and nutrient composition of three morphotypes of Cyperus esculentus tubers and tuber oils were determined. The mean value for length and width of the tuber and one thousand dried tuber weights ranged from 0.98 to 1.31 cm, 0.90 to 1.19 cm, and 598 to 1044 g, respectively. Tubers displayed high level of starch (30.54–33.21 g 100 g−1), lipid (24.91–28.94 g 100 g−1), and sucrose (17.98–20.39 g 100 g−1). The yellow tubers had significantly higher content in lipid compared to black ones. Levels of ascorbic acid, tocopherol, and β-carotene of the three morphotypes differed significantly. Yellow ones (morphotypes 1 and 2) were the richest in tocopherol and the poorest in β-carotene. Saturated fatty acid content of morphotype 2 was significantly lower than that of morphotypes 1 and 3. Morphotype 3 had the significantly lowest PUFA content compared to morphotypes 1 and 2. Morphotype 1 was found to be richer in Ca, Cu, and Mn contents. Al, Mg, P, S, and Si were most abundant in morphotype 2. Morphotype 3 had the highest content of Cl, K, and Zn. PMID:26539305

  15. Effects of superparamagnetic iron oxide nanoparticles on photosynthesis and growth of the aquatic plant Lemna gibba.

    PubMed

    Barhoumi, Lotfi; Oukarroum, Abdallah; Taher, Lotfi Ben; Smiri, Leila Samia; Abdelmelek, Hafedh; Dewez, David

    2015-04-01

    Toxicity of superparamagnetic iron oxide nanoparticles (SPION) was investigated in Lemna gibba plants exposed for 7 days to Fe3O4 (SPION-1), Co0.2Zn0.8Fe2O4 (SPION-2), or Co0.5Zn0.5Fe2O4 (SPION-3) at 0, 12.5, 25, 50, 100, 200 or 400 µg mL(-1). At < 400 µg mL(-1) of SPION exposure, toxicity was indicated by decrease of chlorophyll content, deterioration of photosystem II (PSII) functions, strong production of reactive oxygen species (ROS), and inhibition of growth rate based on fresh weight (52-59 %) or frond number (32-49 %). The performance index of PSII activity was the most sensitive biomarker of PSII functions and decreased by 83, 86, and 79 % for SPION-1, SPION-2, and SPION-3, respectively. According to the change of these biomarkers, the exposure of SPION suspensions to L. gibba caused several alterations to the entire plant cellular system, which may come from both the uptake of nanoparticles and metal ions in the soluble fraction. Our results, based on the change of several biomarkers, showed that these SPION have a complex toxic mode of action on the entire plant system and therefore affects its viability. Therefore, the plant model L. gibba was shown to be a sensitive bioindicator of SPION cellular toxicity and thus can be used in the development of a laboratory bioassay toxicity testing.

  16. A Survey of the Invasive Aquatic and Riparian Plants of the Lower Rio Grande

    DTIC Science & Technology

    2005-04-01

    monocultures in many areas. In 2001 and 2003, surveys were conducted starting below Amistad Reservoir to immediately below Falcon Reservoir to assess...management programs to inhibit further new infestations locally and downstream. In 2001, 20 sites on the Rio Grande River were surveyed from Amistad Reservoir...the 2001 survey, hydrilla was found in Amistad Reservoir and below Falcon Reservoir. In August 2002, hydrilla fragments were observed in plant

  17. Selenium and its compounds in aquatic plant Veronica anagallis-aquatica.

    PubMed

    Kroflič, Ana; Germ, Mateja; Mechora, Špela; Stibilj, Vekoslava

    2016-05-01

    The uptake, distribution and determination of Se and its compounds in macrophyte Veronica anagallis-aquatica were investigated. V. anagallis-aquatica and sediments were sampled in years 2009-2011 and in 2013 in three Slovenian watercourses flowing through an agricultural area, where addition of Se in feedstuffs has been performed for about 25 years. Se content in sediments were up to 0.86 μg g(-1) and in whole plant varied from 0.186 to 1.535 μg g(-1), all on dry weight basis. Se content were measured also in different plant parts; highest content were found in roots and lowest in stems. Separation of extractable Se compounds was performed by ion exchange chromatography and for on-line detection inductively coupled plasma-mass spectrometry was used. The results showed that only approximately 24% of Se in the macrophyte was extracted using enzyme Protease XIV. Extractable Se in plant parts varied from 10.5% in roots to 29.6% in leaves. Identification of Se(IV) and Se(VI) was achieved but no Se-amino acids were detected even at highest Se content. According to our results, we assume that 25 years of Se addition in feedstuff shows minimal impact on Se content in the selected agricultural area. Copyright © 2016 Elsevier Ltd. All rights reserved.

  18. Mineralization of surfactants by microbiota of aquatic plants. [Lemna minor, Typha latifolia

    SciTech Connect

    Federle, T.W.; Schwab, B.S. )

    1989-08-01

    The biodegradation of linear alkylbenzene sulfonate (LAS) and linear alcohol ethoxylate (LAE) by the microbiota associated with duckweed (Lemna minor) and the roots of cattail (Typha latifolia) was investigated. Plants were obtained from a pristine pond and a pond receiving wastewater from a rural laundromat. Cattail roots and duckweed plants were incubated in vessels containing sterile water amended with ({sup 14}C)LAS, ({sup 14}C)LAE, or {sup 14}C-labeled mixed amino acids (MAA). Evolution of {sup 14}CO{sub 2} was determined over time. The microbiota of cattail roots from both ponds mineralized LAS, LAE, and MAA without lag periods, and the rates and extents of mineralization were not significantly affected by the source of the plants. Mineralization of LAS and LAE was more rapid in the rhizosphere than in nearby root-free sediments, which exhibited differences as a function of pond. The microbiota of duckweed readily mineralized LAE and MAA but not LAS. The rate and extent of mineralization were not affected by the source of the duckweed.

  19. Enhanced metabolic and redox activity of vascular aquatic plant Lemna valdiviana under polarization in Direct Photosynthetic Plant Fuel Cell.

    PubMed

    Hubenova, Yolina; Mitov, Mario

    2015-12-01

    In this study, duckweed species Lemna valdiviana was investigated as a photoautotrophycally grown biocatalyst in recently developed Direct Photosynthetic Plant Fuel Cell. Stable current outputs, reaching maximum of 226±11 mА/m(2), were achieved during the operating period. The electricity production is associated with electrons generated through the light-dependent reactions in the chloroplasts as well as the respiratory processes in the mitochondria and transferred to the anode via endogenous electron shuttle, synthesized by the plants as a specific response to the polarization. In parallel, a considerable increase in the content of proteins (47%) and reserve carbohydrates (44%) of duckweeds grown under polarization conditions was established by means of biochemical analyses. This, combined with the electricity generation, makes the technology a feasible approach for the duckweed farming. Copyright © 2014 Elsevier B.V. All rights reserved.

  20. Simultaneous determination of multiclass emerging contaminants in aquatic plants by ultrasound-assisted matrix solid-phase dispersion and GC-MS.

    PubMed

    Aznar, Ramón; Albero, Beatriz; Sánchez-Brunete, Consuelo; Miguel, Esther; Martín-Girela, Isabel; Tadeo, José L

    2017-03-01

    A multiresidue method was developed for the simultaneous determination of 31 emerging contaminants (pharmaceutical compounds, hormones, personal care products, biocides, and flame retardants) in aquatic plants. Analytes were extracted by ultrasound-assisted matrix solid-phase dispersion (UA-MSPD) and determined by gas chromatography-mass spectrometry after sylilation, The method was validated for different aquatic plants (Typha angustifolia, Arundo donax, and Lemna minor) and a semiaquatic cultivated plant (Oryza sativa) with good recoveries at concentrations of 100 and 25 ng g(-1) wet weight, ranging from 70 to 120 %, and low method detection limits (0.3 to 2.2 ng g(-1) wet weight). A significant difference of the chromatographic response was observed for some compounds in neat solvent versus matrix extracts, and therefore, quantification was carried out using matrix-matched standards in order to overcome this matrix effect. Aquatic plants taken from rivers located at three Spanish regions were analyzed, and the compounds detected were parabens, bisphenol A, benzophenone-3, cyfluthrin, and cypermethrin. The levels found ranged from 6 to 25 ng g(-1) wet weight except for cypermethrin that was detected at 235 ng g(-1) wet weight in O. sativa samples.

  1. Effects of Co2 Concentrations and light intensity on photosynthesis of a rootless submerged plant, ceratophyllum demersum L., used for aquatic food production in bioregenerative life support systems

    NASA Astrophysics Data System (ADS)

    Kitaya, Y.; Okayama, T.; Murakami, K.; Takeuchi, T.

    Aquatic higher plants are likely to play an important role in aquatic food production modules in bioregenerative systems for producing feeds for fish, converting CO2 to O2 and remedying water quality in addition to green microalgae. In the present study, the effects of culture conditions on the net photosynthetic rate of a rootless submerged plant, Ceratophyllum demersum L., was investigated to determine the optimum culture conditions for plant function in aquatic food production modules including both plant culture and fish culture systems . The net photosynthetic rate in plants was determined by the increase in dissolved O2 concentrations in a closed vessel containing a plantlet and water. The water in the vessel was aerated sufficiently with a gas containing a known level CO 2 gas mixed with N2 gas before closing the vessel. The CO 2 concentrations in the aerating gas ranged from 0.3 to 100 mmol mol-1 . Photosynthetic photon flux density (PPFD) in the vessel ranged from 0 (dark) to 1.0 mmol m-2 s-1 , which was controlled with a metal halide lamp. Temperature was kept at 28 C. The net photosynthetic rate increased with increasing PPFD levels and was saturated at 0.2 and 0.5 mmol m-2 s-1 PPFD under CO 2 levels of 1.0 and 3.0 mmol mol-1 , respectively. The net photosynthetic rate increased with increasing CO2 levels from 0.3 to 3.0 mmol mol-1 showing the maximum value, 70 nmolO 2 gDW s at 3.0 mmol mol-1 CO2 and gradually decreased with increasing CO 2 levels from 3.0 to 100 mmol mol-1 . The results demonstrate that Ceratophyllum demersum L. could be an efficient CO 2 to O2 converter under a 3.0 mmol mol-1 CO2 level and relatively low PPFD levels in aquatic food production modules.

  2. Aquatic environmental conditions in Chickamauga Reservoir during operation of Sequoyah Nuclear Plant: Fifth annual report (1985)

    SciTech Connect

    Beard, L.M.; Bruggink, D.J.; Buchanan, J.P.; Buckingham, R.A.; Dycus, D.L.; Mulkey, C.E.; Smith, A.O.; Swor, C.T.; Tomljanovich, D.A.; Wade, D.C.

    1986-08-01

    TVA is required by its National Pollutant Discharge Elimination System (NPDES) Permit for Sequoyah Nuclear Plant (SQN) to conduct and report annually on operational nonradiological monitoring to evaluate potential effects of SQN on Chickamauga Reservoir. Because few changes were identified through 1984, the following changes were recommended in June 1985: (1) terminate studies on benthic macroinvertebrates, mollusk bioaccumulation, fish impingement, fish gill netting, fish creel surveys, and water quality at the plant intake and discharge; (2) continue studies on plankton and larval fish with specific changes; and (3) continue cove rotenone studies without change. These recommendations were instituted in July 1985 following approval from the Environmental Protection Agency (EPA). This report evaluates 1985 results for the continued portions and, briefly, for the discontinued portions conducted prior to EPA's approval. Evaluation of water quality data showed that during low flows SQN altered the distribution of DO in the water column at and downstream of the diffusers. Studies to define the extent and duration of the DO alteration will be conducted during spring and summer when SQN resumes operation.

  3. The uptake and distribution of selenium in three aquatic plants grown in Se(IV) solution.

    PubMed

    Mechora, Spela; Stibilj, Vekoslava; Germ, Mateja

    2013-03-15

    The uptake of Se(IV) by Myriophyllum spicatum, Ceratophyllum demersum and Potamogeton perfoliatus, and the effects of Se(IV) on their physiological and biochemical characteristics were studied. Plants were cultivated outdoors under semi-controlled conditions in water solution containing Na selenite (20 μg Se L(-1) and 10 mg Se L(-1)). The higher concentration of Se lowered the photochemical efficiency of PSII in all species studied, while the lower concentration had no effect on any species. The higher concentration of Se lowered respiratory potential in M. spicatum. The response of M. spicatum and C. demersum to Se(IV) regarding chlorophylls was variable, however in the majority of cases, there was a trend of increasing the amount of chlorophylls, while in P. perfoliatus the amount of chlorophyll a decreased. The concentration of Se in plants cultured in 10 mg Se(IV) L(-1) ranged from 436 to 839 μg Se g(-1) DM in M. spicatum, 319 to 988 μg Se g(-1) DM in C. demersum and 310 to 661 μg Se g(-1) DM in P. perfoliatus. The amount of soluble Se compounds in enzyme extracts of high Se treatment was 27% in M. spicatum, 41% in C. demersum and 35% in P. perfoliatus. Se compounds were determined using HPLC-ICP-MS. It was observed that the applied Se(IV) was mainly transformed to insoluble Se.

  4. Economic Potentialities of Some Aquatic Plants Growing in North East Nile Delta, Egypt

    NASA Astrophysics Data System (ADS)

    Abu Ziada, M. E.; Mashaly, I. A.; Abd El-Monem, M.; Torky, M.

    The present study provides quantitative assessment of the vegetative yield, growth characteristics, metabolic products, elemental composition and antimicrobial bioactivity of five common macrohydrophytes: Bolboschoenus glaucus (Cyperaceae), Veronica anagallis-aquatica (Scrophulariaceae), Nymphaea lotus (Nymphaceae), Pistia stratiotes (Araceae) and Myriophyllum spicatum (Haloragidaceae). These plants tend to flourish vegetatively during the summer season (June-August). Their relative growth rate, relative assimilating surface growth rate and net assimilation rate were higher during early vegetative stage (February-May). The highest percentages of protein and lipids content were recorded in Nymphaea, while the crude fiber content was higher in Bolboschoenus than in other species. The macronutrient elements were detected with relatively high concentration and sodium cation appeared to be an essential accumulatent as compared with K, Ca and Mg. Myriophyllum appeared to be the major accumulator species of heavy metals, while Pistia appeared to be the minor one. Sterols, alkaloids, flavonoids, tannins, saponins and resins were detected in these plants. Nymphyaea was found to have the most effective antimicrobial activities than the other studied species.

  5. Ecological Traits of the Algae-Bearing Tetrahymena utriculariae (Ciliophora) from Traps of the Aquatic Carnivorous Plant Utricularia reflexa.

    PubMed

    Šimek, Karel; Pitsch, Gianna; Salcher, Michaela M; Sirová, Dagmara; Shabarova, Tanja; Adamec, Lubomír; Posch, Thomas

    2016-09-10

    Trap fluid of aquatic carnivorous plants of the genus Utricularia hosts specific microbiomes consisting of commensal pro- and eukaryotes of largely unknown ecology. We examined the characteristics and dynamics of bacteria and the three dominant eukaryotes, i.e. the algae-bearing ciliate Tetrahymena utriculariae (Ciliophora), a green flagellate Euglena agilis (Euglenophyta), and the alga Scenedesmus alternans (Chlorophyta), associated with the traps of Utricularia reflexa. Our study focused on ecological traits and life strategies of the highly abundant ciliate whose biomass by far exceeds that of other eukaryotes and bacteria independent of the trap age. The ciliate was the only bacterivore in the traps, driving rapid turnover of bacterial standing stock. However, given the large size of the ciliate and the cell-specific uptake rates of bacteria we estimated that bacterivory alone would likely be insufficient to support its apparent rapid growth in traps. We suggest that mixotrophy based on algal symbionts contributes significantly to the diet and survival strategy of the ciliate in the extreme (anaerobic, low pH) trap-fluid environment. We propose a revised concept of major microbial interactions in the trap fluid where ciliate bacterivory plays a central role in regeneration of nutrients bound in rapidly growing bacterial biomass.

  6. Determination of mercury(II) in aquatic plants using quinoline-thiourea conjugates as a fluorescent probe.

    PubMed

    Feng, Guodong; Ding, Yuanyuan; Gong, Zhiyong; Dai, Yanna; Fei, Qiang

    2013-01-01

    In this study, a quinoline-thiourea conjugate (1-phenyl-3-(quinoline-8-yl) thiourea, PQT) was synthesized and used as a fluorescence sensor to detect mercury ion. The observation is coincident with the well-documented phenomenon that a thiocarbonyl-containing group on a fluorochrome quenches the fluorescence due to the heavy atom effect of the S atom. The large fluorescence enhancement of PQT in the buffered MeCN-water mixture (1/1 v/v; HEPES 100 mM; pH 8.0) was caused by the Hg(2+) induced transformation of the thiourea function into a urea group. As such, protic solvents can be ascribed to hydrogen bond formation on the carbonyl oxygen to reduce the internal conversion rate. The fluorescence intensity of PQT was enhanced quantitatively with an increase in the concentration of mercury ion. The limit of detection of Hg(2+) was 7.5 nM. The coexistence of other metal ions with mercury had no obvious influence on the detection of mercury. A quinolone-thiourea conjugate was used as a fluorescent probe to detect Hg(2+) in aquatic plants and the experimental results were satisfactory.

  7. Root length of aquatic plant, Lemna minor L., as an optimal toxicity endpoint for biomonitoring of mining effluents.

    PubMed

    Gopalapillai, Yamini; Vigneault, Bernard; Hale, Beverley A

    2014-10-01

    Lemna minor, a free-floating macrophyte, is used for biomonitoring of mine effluent quality under the Metal Mining Effluent Regulations (MMER) of the Environmental Effects Monitoring (EEM) program in Canada and is known to be sensitive to trace metals commonly discharged in mine effluents such as Ni. Environment Canada's standard toxicity testing protocol recommends frond count (FC) and dry weight (DW) as the 2 required toxicity endpoints-this is similar to other major protocols such as those by the US Environmental Protection Agency (USEPA) and the Organisation for Economic Co-operation and Development (OECD)-that both require frond growth or biomass endpoints. However, we suggest that similar to terrestrial plants, average root length (RL) of aquatic plants will be an optimal and relevant endpoint. As expected, results demonstrate that RL is the ideal endpoint based on the 3 criteria: accuracy (i.e., toxicological sensitivity to contaminant), precision (i.e., lowest variance), and ecological relevance (metal mining effluents). Roots are known to play a major role in nutrient uptake in conditions of low nutrient conditions-thus having ecological relevance to freshwater from mining regions. Root length was the most sensitive and precise endpoint in this study where water chemistry varied greatly (pH and varying concentrations of Ca, Mg, Na, K, dissolved organic carbon, and an anthropogenic organic contaminant, sodium isopropyl xanthates) to match mining effluent ranges. Although frond count was a close second, dry weight proved to be an unreliable endpoint. We conclude that toxicity testing for the floating macrophyte should require average RL measurement as a primary endpoint.

  8. Impacts of water development on aquatic macroinvertebrates, amphibians, and plants in wetlands of a semi-arid landscape

    USGS Publications Warehouse

    Euliss, Ned H.; Mushet, David M.

    2004-01-01

    We compared the macroinvertebrate and amphibian communities of 12 excavated and 12 natural wetlands in western North Dakota, USA, to assess the effects of artificially lengthened hydroperiods on the biotic communities of wetlands in this semi-arid region. Excavated wetlands were much deeper and captured greater volumes of water than natural wetlands. Most excavated wetlands maintained water throughout the study period (May to October 1999), whereas most of the natural wetlands were dry by June. Excavated wetlands were largely unvegetated or contained submergent and deep-marsh plant species. The natural wetlands had two well-defined vegetative zones populated by plant species typical of wet meadows and shallow marshes. Excavated wetlands had a richer aquatic macroinvertebrate community that included several predatory taxa not found in natural wetlands. Taxa adapted to the short hydroperiods of seasonal wetlands were largely absent from excavated wetlands. The amphibian community of natural and excavated wetlands included the boreal chorus frog (Pseudacris maculata), northern leopard frog (Rana pipiens), plains spadefoot (Scaphiopus bombifrons), Woodhouse's toad (Bufo woodhousii woodhousii), and tiger salamander (Ambystoma tigrinum). The plains spadefoot occurred only in natural wetlands while tiger salamanders occurred in all 12 excavated wetlands and only one natural wetland. Boreal chorus frogs and northern leopard frogs were present in both wetland types; however, they successfully reproduced only in wetlands lacking tiger salamanders. Artificially extending the hydroperiod of wetlands by excavation has greatly influenced the composition of native biotic communities adapted to the naturally short hydroperiods of wetlands in this semi-arid region. The compositional change of the biotic communities can be related to hydrological changes and biotic interactions, especially predation related to excavation.

  9. Effects of an aquatic plant and suspended clay on the activity of fish toxicants

    USGS Publications Warehouse

    Gilderhus, P.A.

    1982-01-01

    Rotenone, antimycin, permethrin, pydrin, and Salicylanilide I were tested for their toxicities against fathead minnows (Pimephales promelas) in the presence of Canadian waterweed (Elodea canadensis) or suspended clay. The plants had little effect on the activity of rotenone and antimycin but substantially reduced the activity of permethrin and pydrin (synthetic pyrethroids). Bentonite severely inhibited the activity of all chemicals tested. Salicylanilide I was affected least and pydrin most (27 times as much pydrin was required when I g/liter of bentonite was present in 96-hour tests). The efficacy of the registered fish toxicants rotenone and antimycin is probably not significantly affected by vegetation under field conditions, but is greatly reduced by suspended bentonite clay.

  10. Identification and characterization of a spore-like morphotype in chronically starved Mycobacterium avium subsp. paratuberculosis cultures.

    PubMed

    Lamont, Elise A; Bannantine, John P; Armién, Aníbal; Ariyakumar, Don Sanjiv; Sreevatsan, Srinand

    2012-01-01

    Mycobacteria are able to enter into a state of non-replication or dormancy, which may result in their chronic persistence in soil, aquatic environments, and permissive hosts. Stresses such as nutrient deprivation and hypoxia provide environmental cues to enter a persistent state; however, a clear definition of the mechanism that mycobacteria employ to achieve this remains elusive. While the concept of sporulation in mycobacteria is not novel, it continues to spark controversy and challenges our perceptions of a non-replication. We investigated the potential role of sporulation in one-year old broth cultures of Mycobacterium subsp. paratuberculosis (MAP). We show that dormant cultures of MAP contain a mix of vegetative cells and a previously unknown morphotype resembling a spore. These spore-like structures can be enriched for using sporulating media. Furthermore, purified MAP spore forms survive exposure to heat, lysozyme and proteinase K. Heat-treated spores are positive for MAP 16SrRNA and IS900. MAP spores display enhanced infectivity as well as maintain acid-fast characteristics upon germination in a well-established bovine macrophage model. This is the first study to demonstrate a new MAP morphotype possessing spore-like qualities. Data suggest that sporulation may be a viable mechanism by which MAP accomplishes persistence in the host and/or environment. Thus, our current understanding of mycobacterial persistence, pathogenesis, epidemiology and rational drug and vaccine design may need to be reevaluated.

  11. Identification and Characterization of a Spore-Like Morphotype in Chronically Starved Mycobacterium avium Subsp. Paratuberculosis Cultures

    PubMed Central

    Lamont, Elise A.; Bannantine, John P.; Armién, Aníbal; Ariyakumar, Don Sanjiv; Sreevatsan, Srinand

    2012-01-01

    Mycobacteria are able to enter into a state of non-replication or dormancy, which may result in their chronic persistence in soil, aquatic environments, and permissive hosts. Stresses such as nutrient deprivation and hypoxia provide environmental cues to enter a persistent state; however, a clear definition of the mechanism that mycobacteria employ to achieve this remains elusive. While the concept of sporulation in mycobacteria is not novel, it continues to spark controversy and challenges our perceptions of a non-replication. We investigated the potential role of sporulation in one-year old broth cultures of Mycobacterium subsp. paratuberculosis (MAP). We show that dormant cultures of MAP contain a mix of vegetative cells and a previously unknown morphotype resembling a spore. These spore-like structures can be enriched for using sporulating media. Furthermore, purified MAP spore forms survive exposure to heat, lysozyme and proteinase K. Heat-treated spores are positive for MAP 16SrRNA and IS900. MAP spores display enhanced infectivity as well as maintain acid-fast characteristics upon germination in a well-established bovine macrophage model. This is the first study to demonstrate a new MAP morphotype possessing spore-like qualities. Data suggest that sporulation may be a viable mechanism by which MAP accomplishes persistence in the host and/or environment. Thus, our current understanding of mycobacterial persistence, pathogenesis, epidemiology and rational drug and vaccine design may need to be reevaluated. PMID:22292005

  12. Green synthesis of gold nanoparticles using a cheap Sphaeranthus indicus extract: Impact on plant cells and the aquatic crustacean Artemia nauplii.

    PubMed

    Balalakshmi, Chinnasamy; Gopinath, Kasi; Govindarajan, Marimuthu; Lokesh, Ravi; Arumugam, Ayyakannu; Alharbi, Naiyf S; Kadaikunnan, Shine; Khaled, Jamal M; Benelli, Giovanni

    2017-08-01

    The impact of green-fabricated gold nanoparticles on plant cells and non-target aquatic species is scarcely studied. In this research, we reported an environment friendly technique for the synthesis of gold nanoparticles (Au NPs) using the Sphaeranthus indicus leaf extract. The formation of the metal NPs was characterized by UV-Visible and FT-IR spectroscopy, XRD, SEM and TEM analyses. The UV-Visible spectra of Au NPs showed a surface plasmon resonance peak at 531nm. FT-IR analysis indicated functional bio-molecules associated with Au NPs formation. The crystalline nature of Au nanoparticles was confirmed by their XRD diffraction pattern. TEM revealed the spherical shape with a mean particle size of 25nm. Au NPs was tested at 0, 1, 3, 5, 7 and 10% doses in mitotic cell division assays, pollen germination experiments, and in vivo toxicity trials against the aquatic crustacean Artemia nauplii. Au NPs did not show any toxic effects on plant cells and aquatic invertebrates. Notably, Au NPs promoted mitotic cell division in Allium cepa root tip cells and germination of Gloriosa superba pollen grains. Au NPs showed no mortality on A. nauplii, all the tested animals showed 100% survivability. Therefore, these Au NPs have potential applications in the development of pollen germination media and plant tissue culture. Copyright © 2017 Elsevier B.V. All rights reserved.

  13. Assessment of macro and microelement accumulation capability of two aquatic plants.

    PubMed

    Baldantoni, Daniela; Alfani, Anna; Di Tommasi, Paul; Bartoli, Giovanni; De Santo, Amalia Virzo

    2004-07-01

    The concentrations of four macroelements (C, N, P, S) and eight trace metals (Cd, Cr, Cu, Fe, Mn, Ni, Pb, Zn) were measured in the leaves and roots of the emergent plant, Phragmites communis Trin., and in the shoots and roots of the submersed Najas marina L., taken from Lake Averno (Naples, Italy). Phragmites communis leaves showed higher concentrations of carbon, nitrogen and phosphorus than roots, while the roots exhibited significantly higher concentrations of sulphur and trace metals. Najas marina roots also showed higher concentrations of sulphur and trace metals than shoots, but these differences were less marked than in Phragmites communis except for sulphur. Sulphur was the only macronutrient to show the highest concentrations in the roots. Phragmites communis roots had higher values of Cr, Cu, Fe, Mn and Ni than Najas marina roots. By contrast, Cd, Cr, Fe, Ni, Pb and Zn concentrations were higher in Najas marina shoots than in Phragmites communis leaves. Phragmites communis, available through the year, showing high capability to accumulate trace metals in the roots, appears a good monitor of lake contamination, better than Najas marina.

  14. Contribution of Wastewater Treatment Plant Effluents to Nutrient Dynamics in Aquatic Systems: A Review

    NASA Astrophysics Data System (ADS)

    Carey, Richard O.; Migliaccio, Kati W.

    2009-08-01

    Excessive nutrient loading (considering nitrogen and phosphorus) is a major ongoing threat to water quality and here we review the impact of nutrient discharges from wastewater treatment plants (WWTPs) to United States (U.S.) freshwater systems. While urban and agricultural land uses are significant nonpoint nutrient contributors, effluent from point sources such as WWTPs can overwhelm receiving waters, effectively dominating hydrological characteristics and regulating instream nutrient processes. Population growth, increased wastewater volumes, and sustainability of critical water resources have all been key factors influencing the extent of wastewater treatment. Reducing nutrient concentrations in wastewater is an important aspect of water quality management because excessive nutrient concentrations often prevent water bodies from meeting designated uses. WWTPs employ numerous physical, chemical, and biological methods to improve effluent water quality but nutrient removal requires advanced treatment and infrastructure that may be economically prohibitive. Therefore, effluent nutrient concentrations vary depending on the particular processes used to treat influent wastewater. Increasingly stringent regulations regarding nutrient concentrations in discharged effluent, along with greater freshwater demand in populous areas, have led to the development of extensive water recycling programs within many U.S. regions. Reuse programs provide an opportunity to reduce or eliminate direct nutrient discharges to receiving waters while allowing for the beneficial use of reclaimed water. However, nutrients in reclaimed water can still be a concern for reuse applications, such as agricultural and landscape irrigation.

  15. Ammonia stress on nitrogen metabolism in tolerant aquatic plant-Myriophyllum aquaticum.

    PubMed

    Zhou, Qingyang; Gao, Jingqing; Zhang, Ruimin; Zhang, Ruiqin

    2017-09-01

    Ammonia has been a major reason of macrophyte decline in the water environment, and ammonium ion toxicity should be seen as universal, even in species frequently labeled as "NH4(+) specialists". To study the effects of high NH4(+)-N stress of ammonium ion nitrogen on tolerant submerged macrophytes and investigate the pathways of nitrogen assimilation in different organisms, Myriophyllum aquaticum was selected and treated with various concentrations of ammonium ions at different times. Increasing of ammonium concentration leads to an overall increase in incipient ammonia content in leaves and stems of plants. In middle and later stages, high concentrations of NH4(+) ion nitrogen taken up by M. aquaticum decreased, whereas the content of NO3(-) ion nitrogen increased. Moreover, in M. aquaticum, the activities of the enzymes nitrate reductase, glutamine synthetase and asparagine synthetase changed remark