Science.gov

Sample records for aquatic plant morphotypes

  1. 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…

  2. Aquatic plant management

    SciTech Connect

    Not Available

    1991-01-01

    Twelve fact sheets are presented which cover different forms of aquatic plant management in Guntersville Reservoir. These cover the introduction of grass carp and other biological controls, drawdown of reservoir water, herbicide use, harvesting, impacts on recreational uses, and other issues of concern. (SM)

  3. Introduced aquatic plants and algae

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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...

  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. 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.

  6. 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

  7. 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.

  8. 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

  9. 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.

  10. 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…

  11. 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.

  12. 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...

  13. 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

  14. 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. PMID:21902696

  15. Phytoaccumulation of heavy metals by aquatic plants.

    PubMed

    Kamal, M; Ghaly, A E; Mahmoud, N; Côté, R

    2004-02-01

    Three aquatic plants were examined for their ability to remove heavy metals from contaminated water: parrot feather (Myriophylhum aquaticum), creeping primrose (Ludwigina palustris), and water mint (Mentha aquatic). The plants were obtained from a Solar Aquatic System treating municipal wastewater. All the three plants were able to remove Fe, Zn, Cu, and Hg from the contaminated water. The average removal efficiency for the three plant species was 99.8%, 76.7%, 41.62%, and 33.9% of Hg, Fe, Cu, and Zn, respectively. The removal rates of zinc and copper were constant (0.48 mg/l/day for Zn and 0.11 mg/l/day for Cu), whereas those of iron and mercury were dependent on the concentration of these elements in the contaminated water and ranged from 7.00 to 0.41 mg/l/day for Fe and 0.0787 to 0.0002 mg/l/day for Hg. Parrot feather showed greater tolerance to toxicity followed by water mint and creeping primrose. The growth of creeping primrose was significantly affected by heavy metal toxicity. The selectivity of heavy metals for the three plant species was the same (Hg>Fe>Cu>Zn). The mass balance preformed on the system showed that about 60.45-82.61% of the zinc and 38.96-60.75% of the copper were removed by precipitation as zinc phosphate and copper phosphate, respectively. PMID:14680885

  16. 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.

  17. 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.

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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...

  19. 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.

  20. 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. PMID:23609308

  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. 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

  4. 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).

  5. THE IMPACT OF AQUATIC PLANTS AND THEIR MANAGEMENT TECHNIQUES ON THE AQUATIC RESOURCES OF THE UNITED STATES: AN OVERVIEW

    EPA Science Inventory

    This paper provides an assessment of nuisance aquatic plants and the problems associated with their control in the United States. Major emphasis is given to the Sun Belt states where aquatic plant control is critical due to introduction of exotic plants and extended growing seaso...

  6. 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. PMID:25148081

  7. 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

  8. 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

  9. 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. PMID:23752400

  10. USE OF VASCULAR AQUATIC PLANTS IN PHYTOTOXICITY STUDIES WITH SEDIMENTS

    EPA Science Inventory

    Sediments and rooted aquatic plants are major components of wetland systems. ediments in these systems act as sinks and reservoirs for organic and inorganic pollutants that are adsorbed to sediment particles or contained-in interstitial water that exists between the particle spac...

  11. 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.

  12. 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.

  13. 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.

  14. 33 CFR Appendix B to Part 273 - Information Requirements for Aquatic Plant Control Program Reports

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 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...

  15. 33 CFR Appendix A to Part 273 - Aquatic Plant Control Program Legislative Authority

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 33 Navigation and Navigable Waters 3 2012-07-01 2012-07-01 false Aquatic Plant Control Program 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—Aquatic Plant Control Program...

  16. 33 CFR Appendix A to Part 273 - Aquatic Plant Control Program Legislative Authority

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 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—Aquatic Plant Control Program Legislative Authority Section 104 of the Rivers and Harbors Act, approved...

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

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 33 Navigation and Navigable Waters 3 2013-07-01 2013-07-01 false Aquatic Plant Control Program... OF THE ARMY, DEPARTMENT OF DEFENSE AQUATIC PLANT CONTROL Pt. 273, App. A Appendix A to Part 273—Aquatic Plant Control Program Legislative Authority Section 104 of the Rivers and Harbors Act, approved...

  18. 33 CFR Appendix A to Part 273 - Aquatic Plant Control Program Legislative Authority

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 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—Aquatic Plant Control Program Legislative Authority Section 104 of the Rivers and Harbors Act, approved...

  19. 33 CFR Appendix A to Part 273 - Aquatic Plant Control Program Legislative Authority

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 3 2011-07-01 2011-07-01 false Aquatic Plant Control Program... OF THE ARMY, DEPARTMENT OF DEFENSE AQUATIC PLANT CONTROL Pt. 273, App. A Appendix A to Part 273—Aquatic Plant Control Program Legislative Authority Section 104 of the Rivers and Harbors Act, approved...

  20. 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.

  1. 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.

  2. [90Sr and 137Cs in higher aquatic plants of the Chernobyl nuclear plant exlusion zone

    PubMed

    Gudkov, D I; Derevets, V V; Kuz'menko, M I; Nazarov, A B

    2001-01-01

    The content of radionuclides 90Sr and 137Cs in higher aquatic plants of water objects within Chernobyl NPP exclusion zone has been analysed. Biodiversity of phytocenose was studied and species-indicators of radioactive contamination were revealed. The seasonal dynamics of radionuclide content in macrophytes was studied and the role of main aquatic plant clumps in processes of 137Cs and 90Sr distribution in abiotic component of biohydrocenose was demonstrated. PMID:11402559

  3. 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. PMID:26247406

  4. Shifts in Rhizoplane Communities of Aquatic Plants after Cadmium Exposure

    PubMed Central

    Stout, Lisa M.; Nüsslein, Klaus

    2005-01-01

    In this study we present the comparative molecular analysis of bacterial communities of the aquatic plant Lemna minor from a contaminated site (RCP) and from a laboratory culture (EPA), as well as each of these with the addition of cadmium. Plants were identified as L. minor by analysis of the rpl16 chloroplast region. Comparative bacterial community studies were based on the analyses of 16S rRNA clone libraries, each containing about 100 clones from the root surfaces of plants. Bacterial communities were compared at three phylogenetic levels of resolution. At the level of bacterial divisions, differences in diversity index scores between treatments, with and without cadmium within the same plant type (EPA or RCP), were small, indicating that cadmium had little effect. When we compared genera within the most dominant group, the β-proteobacteria, differences between unamended and cadmium-amended libraries were much larger. Bacterial diversity increased upon cadmium addition for both EPA and RCP libraries. Analyses of diversity at the phylotype level showed parallel shifts to more even communities upon cadmium addition; that is, percentage changes in diversity indices due to cadmium addition were the same for either plant type, indicating that contamination history might be independent of disturbance-induced diversity shifts. At finer phylogenetic levels of resolution, the effects of cadmium addition on bacterial communities were very noticeable. This study is a first step in understanding the role of aquatic plant-associated microbial communities in phytoremediation of heavy metals. PMID:15870338

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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...

  6. Mercury uptake and accumulation by four species of aquatic plants.

    PubMed

    Skinner, Kathleen; Wright, Nicole; Porter-Goff, Emily

    2007-01-01

    The effectiveness of four aquatic plants including water hyacinth (Eichornia crassipes), water lettuce (Pistia stratiotes), zebra rush (Scirpus tabernaemontani) and taro (Colocasia esculenta) were evaluated for their capabilities in removing mercury from water. The plants were exposed to concentrations of 0 mg/L, 0.5 mg/L or 2 mg/L of mercury for 30 days. Assays were conducted using both Microtox (water) and cold vapor Atomic Absorption Spectroscopy (AAS) (roots and water). The Microtox results indicated that the mercury induced acute toxicity had been removed from the water. AAS confirmed an increase of mercury within the plant root tissue and a corresponding decrease of mercury in the water. All species of plants appeared to reduce mercury concentrations in the water via root uptake and accumulation. Water lettuce and water hyacinth appeared to be the most effective, followed by taro and zebra rush, respectively. PMID:16781033

  7. 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

  8. Aquatic hyphomycetes as endophytes of riparian plant roots.

    PubMed

    Sati, S C; Belwal, M

    2005-01-01

    Eighteen species of aquatic hyphomycetes were recorded as root endophytes in roots of living plants including grasses and pteridophytes from wet fields near ravine areas. Alatospora acuminata, A. pulchella, Acaulopage tetraceros, Anguillospora crassa, Campylospora chaetocladia, Lemonniera cornuta, L. pseudofloscula, L. terrestris, Pestalotiopsis submersus and Tetrachaetum elegans were found for the first time as root endophytes. A. longissima, Campylospora purvula, Clavariopsis aquatica, Cylindrocarpon aquaticum, Heliscus lugdunensis, Lunulospora curvula, Tetracladium marchalianum and T. setigerum, which were known previously as root endophytes, are reported here on new hosts. Maximum occurrence was found in November and December. PMID:16389955

  9. 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.

  10. 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

  11. 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.

  12. 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).

  13. 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

  14. 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

  15. 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

  16. 33 CFR Appendix B to Part 273 - Information Requirements for Aquatic Plant Control Program Reports

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 33 Navigation and Navigable Waters 3 2013-07-01 2013-07-01 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 to Part 273—Information Requirements...

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

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 3 2011-07-01 2011-07-01 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. 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 to Part 273—Information Requirements...

  19. 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.

  20. Toxicity of coal gasifier solid waste to the aquatic plants Selenastrum capricornutum and Spirodela oligorhiza

    SciTech Connect

    Klaine, S.J.

    1985-10-01

    Classical assessment of aquatic toxicity has focused on fish and invertebrates primarily due to their economic importance. However, increased awareness of the role of aquatic vegetation as primary producers in aquatic systems has stimulated their use in aquatic hazards evaluations. This paper presents the results of solid waste leaching tests using a procedure which was designed to mimic landfilling of solid waste. Results are reported for leachate analysis of the ash agglomerate and the relative toxicity of this leachate to Selenastrum capricornutum (a unicellular green alga) and Spirodela oligorhiza (a floating aquatic vascular plant).

  1. 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

  2. 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.

  3. Heavy metal concentrations (Cd, Cu and Pb) in five aquatic plant species in Tasik Chini, Malaysia

    NASA Astrophysics Data System (ADS)

    Ebrahimpour, M.; Mushrifah, I.

    2008-04-01

    The purpose of this study was to determine the levels of heavy metals namely cadmium (Cd), copper (Cu) and lead (Pb) in the five aquatic plants. For this purpose, the concentration of heavy metals were measured in water and in the five aquatic plant species, Lepironia articulata, Pandanus helicopus, Scirpus grossus, Cabomba furcata and Nelumbo nucifera, in 15 sites from Tasik Chini. The concentrations were different among the plant species as well as among the parts of plants. The highest concentration of heavy metals among the aquatic plants and plant parts was found in the roots of S. grossus. The concentrations of Cd in the leaves and stems of submerged aquatic plant, C . furcata, were higher than concentration of Cd in the leaves and stems of emergent aquatic plant and floating leaf plant. The concentration of Cu in the stem of C. furcata was greater than that in the leaf, while the concentration of Cd was more in the leaf than in the stem. The heavy metal contents of the aquatic plants were in descending order of Pb > Cu > Cd. The metal concentration quotient of leaves/roots and stems/roots (ML/MR and MS/MR) were calculated. The highest internal translocation was found in P. helicopus, while the lowest internal translocation was found in S. grossus.

  4. 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

  5. Phytoaccumulation of zinc by the aquatic plant, Lemna gibba L.

    PubMed

    Khellaf, Nabila; Zerdaoui, Mostefa

    2009-12-01

    The uptake of zinc (Zn) by the duckweed Lemna gibba L., native to the north-east region of Algeria, was investigated in quarter Coïc solutions enriched with 6.0, 10.0, 14.0 and 18.0 mg l(-1) of Zn supplied as zinc sulphate (ZnSO(4)). Zinc concentrations were measured in the water daily and in duckweed biomass at the end of the experiments. These results showed that under experimental conditions (pH=6.0+/-0.1, T=21+/-1 degrees C, photoperiod=12 h/j), L. gibba was able to accumulate in its biomass 4.23; 15.62; 23.88 and 25.81 mg g(-1) DM, respectively for the four initial concentrations selected. At these concentrations, the metal removed percentages were 61-71%. The mass balance performed on the system showed that about 49-68% of Zn (depending on the initial concentration in water) was removed by precipitation as zinc phosphate. The results showed that this aquatic plant can be successfully used for Zn removal. PMID:19581083

  6. 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

  7. 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. PMID:26403243

  8. 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...

  9. 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. PMID:25514395

  10. 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.

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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...

  12. 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. PMID:27474848

  13. Acute and chronic toxicity testing of bisphenol A with aquatic invertebrates and plants.

    PubMed

    Mihaich, Ellen M; Friederich, Urs; Caspers, Norbert; Hall, A Tilghman; Klecka, Gary M; Dimond, Stephen S; Staples, Charles A; Ortego, Lisa S; Hentges, Steven G

    2009-07-01

    Bisphenol A (BPA, 4,4'-isopropylidine diphenol) is a commercially important chemical used primarily as an intermediate in the production of polycarbonate plastic and epoxy resins. Extensive effect data are currently available, including long-term studies with BPA on fish, amphibians, crustaceans, and mollusks. The aim of this study was to perform additional tests with a number of aquatic invertebrates and an aquatic plant. These studies include acute tests with the midge (Chironomus tentans) and the snail (Marisa cornuarietis), and chronic studies with rotifers (Brachionus calyciflorus), amphipods (Hyalella azteca), and plants (Lemna gibba). The effect data on different aquatic invertebrate and plant species presented in this paper correspond well with the effect and no-effect concentrations (NOECs) available from invertebrate studies in the published literature and are within the range found for other aquatic species tested with BPA. PMID:19327838

  14. Adhesion and splash dispersal of Salmonella enterica Typhimurium on tomato leaflets: effects of rdar morphotype and trichome density.

    PubMed

    Cevallos-Cevallos, Juan M; Gu, Ganyu; Danyluk, Michelle D; van Bruggen, Ariena H C

    2012-11-01

    Salmonella enterica strains with rdar (red dry and rough) and saw (smooth and white) morphotypes have previously been associated with tomato outbreaks but the dispersal mechanisms of these morphotypes are still poorly understood. In this study, Salmonella adhesion was distinguished from attachment by comparing different contact periods. Initial adhesion of rdar and saw morphotypes of Salmonella was compared in relation to tomato plants with different leaf trichome densities. Trichome densities were increased or reduced by treatment with jasmonic or salicylic acid, respectively. The overall effect of Salmonella morphotype and trichome density on splash dispersal was assessed in a rain simulator and correlated to cell hydrophobicity and initial adhesion. The presence of the rdar morphotype increased initial adhesion at high trichome densities but not at low trichome densities. Attachment of the rdar strain occurred after 30s contact time regardless of trichome density. Splash dispersal was slightly further for the saw morphotype than the rdar morphotype of S. enterica at all trichome densities. Salmonella cells of both morphotypes survived significantly better on the surface of high trichome density leaflets. PMID:23141646

  15. 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. PMID:25496742

  16. 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

  17. 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…

  18. EFFECT OF ACIDIC CONDITIONS ON CADMIUM UPTAKE BY THREE AQUATIC PLANTS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Acidic runoff from mining and storage of mined materials creates an undesirable environmental impact on both flora and fauna. Presence of heavy metals such as Cadmium (CD) creates an additional negative factor in acidic environments. Accumulation of Cd in plant tissues of aquatic vascular plants i...

  19. 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. PMID:19696734

  20. 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.

  1. 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. PMID:26386206

  2. [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. PMID:23717994

  3. 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

    2015-12-01

    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

  4. 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

  5. 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.

  6. 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. PMID:26994429

  7. 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

  8. 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.

  9. 33 CFR Appendix C to Part 273 - Information Requirements for Aquatic Plant Control Program Environmental Impact Statements

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Aquatic Plant Control Program Environmental Impact Statements C Appendix C to Part 273 Navigation and.... 273, App. C Appendix C to Part 273—Information Requirements for Aquatic Plant Control Program... specifically as possible. c. Severity of infestation. Discuss the degree and importance of the pest problem....

  10. 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. PMID:23028018

  11. Using in situ hyperspectral reflectance data to distinquish nine aquatic plant species

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In situ hyperspectral reflectance data were studied at 50 bands (10 nm bandwidth) over the 400 to 900 nm spectral range to determine their potential for distinguishing among nine aquatic plant species: American lotus [Nelumbo lutea (Willd.) Pers.], American pondweed (Potamogeton nodusus Poir.), gian...

  12. 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. PMID:22567707

  13. Extraction of /sup 14/C-labeled photosynthate from aquatic plants with dimethyl sulfoxide (DMSO)

    SciTech Connect

    Filbin, G.J.; Hough, R.A.

    1984-03-01

    DMSO was tested as a solvent to extract /sup 14/C-labeled photosynthate from three species of aquatic plants in photosynthesis measurements and compared with the dry oxidation method for plant radioassay. Extraction efficiency was in the range of 96-99% of fixed /sup 14/C, and precision was comparable to, or better than, that obtained with dry oxidation. The method is simple and inexpensive, and for fresh tissue the same sample extracts can be used for chlorophyll analyses.

  14. Chemical defenses promote persistence of the aquatic plant Micranthemum umbrosum.

    PubMed

    Parker, John D; Collins, Dwight O; Kubanek, Julia; Sullards, M Cameron; Bostwick, David; Hay, Mark E

    2006-04-01

    Five of the most common macrophytes from an aquaculture facility with high densities of the herbivorous Asian grass carp (Ctenopharyngodon idella) were commonly unpalatable to three generalist consumers-grass carp and the native North American crayfishes Procambarus spiculifer and P. acutus. The rooted vascular plant Micranthemum umbrosum comprised 89% of the total aboveground plant biomass and was unpalatable to all three consumers as fresh tissues, as homogenized pellets, and as crude extracts. Bioassay-guided fractionation of the crude extract from M. umbrosum led to four previously known compounds that each deterred feeding by at least one consumer: 3,4,5-trimethoxyallylbenzene (1) and three lignoids: beta-apopicropodophyllin (2); (-)-(3S,4R,6S)-3-(3',4'-methylenedioxy-alpha-hydroxybenzyl)-4-(3'',4''-dimethoxybenzyl)butyrolactone (3); and (-)-hibalactone (4). None of the remaining four macrophytes produced a chemically deterrent extract. A 16-mo manipulative experiment showed that the aboveground biomass of M. umbrosum was unchanged when consumers were absent, but the biomass of Ludwigia repens, a plant that grass carp preferentially consumed over M. umbrosum, increased over 300-fold. Thus, selective feeding by grass carp effectively eliminates most palatable plants from this community and promotes the persistence of the chemically defended M. umbrosum, suggesting that plant defenses play critical yet understudied roles in the structure of freshwater plant communities. PMID:16586032

  15. Chromium stress induced alterations in biochemical and enzyme metabolism in aquatic and terrestrial plants.

    PubMed

    Ganesh, K Sankar; Baskaran, L; Rajasekaran, S; Sumathi, K; Chidambaram, A L A; Sundaramoorthy, P

    2008-06-01

    Water is seriously polluted by the discharge of various industrial wastewater containing heavy metals. Among them, chromium is considered to be toxic to living organisms and it is released mostly from tanneries. The chromium-contaminated water is discharged into nearby water bodies and it affects both aquatic and terrestrial plants. So the present experiment was conducted with an aquatic plant, water lettuce (Pistia stratiotes L.) and a terrestrial plant soybean (Glycine max L. Merr.). They were treated with different concentrations (0, 5, 10, 25, 50, 100 and 200mg/L) of potassium dichromate solution. The biochemical parameters such as total chlorophyll, carotenoid, protein and amino acid content and the enzymatic activities like catalase and peroxidase were estimated. The accumulation of chromium was also analysed in both the plants. All the biochemical contents and enzyme activities of water lettuce and soybean seedlings showed a great variation with respect to the increase in chromium concentrations. The accumulation of chromium increased gradually with the increase of chromium concentrations. Total inhibition of all the parameters were observed at 300 mg/L chromium concentration. The terrestrial plant soybean was sensitive than the aquatic plant water lettuce towards chromium stress. PMID:18206355

  16. 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

  17. 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. PMID:26904852

  18. 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.

  19. 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. PMID:24239820

  20. PREDICTING CHEMICAL ACCUMULATION IN SHOOTS OF AQUATIC PLANTS

    EPA Science Inventory

    Chemical exchange dynamics expected for diffusive transfer of a chemical between aqueous solution and plant shoots, and expected bioconcentration based on partitioning properties of the chemical, are explored by using a three-compartment model. he model utilizes three dynamic com...

  1. 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.

  2. 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.

  3. 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.

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

    PubMed

    Jackrel, Sara L; Wootton, J Timothy

    2015-04-22

    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

  5. 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

  6. 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.

  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. 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.

  9. 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.

  10. 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

  11. Ocean Circulation Modeling for Aquatic Dispersion of Liquid Radioactive Effluents from Nuclear Power Plants

    SciTech Connect

    Chung, Y.G.; Lee, G.B.; Bang, S.Y.; Choi, S.B.; Lee, S.U.; Yoon, J.H.; Nam, S.Y.; Lee, H.R.

    2006-07-01

    Recently, three-dimensional models have been used for aquatic dispersion of radioactive effluents in relation to nuclear power plant siting based on the Notice No. 2003-12 'Guideline for investigating and assessing hydrological and aquatic characteristics of nuclear facility site' of the Ministry of Science and Technology (MOST) in Korea. Several nuclear power plants have been under construction or planed, which are Shin-Kori Unit 1 and 2, Shin-Wolsong Unit 1 and 2, and Shin-Ulchin Unit 1 and 2. For assessing the aquatic dispersion of radionuclides released from the above nuclear power plants, it is necessary to know the coastal currents around sites which are affected by circulation of East Sea. In this study, a three dimensional hydrodynamic model for the circulation of the East Sea of Korea has been developed as the first phase, which is based on the RIAMOM (Research Institute of Applied Mechanics' Ocean Model, Kyushu University, Japan). The model uses the primitive equation with hydrostatic approximation, and uses Arakawa-B grid system horizontally and Z coordinate vertically. Model domain is 126.5 deg. E to 142.5 deg. E of east longitude and 33 deg. N and 52 deg. N of the north latitude. The space of the horizontal grid was 1/12 deg. to longitude and latitude direction and vertical level was divided to 20. This model uses Generalized Arakawa Scheme, Slant Advection, and Mode-Splitting Method. The input data were from JODC (Japan Oceanographic Data Center), KNFRDI (Korea National Fisheries Research and Development Institute), and ECMWF (European Center for Medium-Range Weather Forecasts). The modeling results are in fairly good agreement with schematic patterns of the surface circulation in the East Sea/Japan Sea. The local current model and aquatic dispersion model of the coastal region will be developed as the second phase. The oceanic dispersion experiments will be also carried out by using ARGO Drifter around a nuclear power plant site. (authors)

  12. Water vapor and air transport through ponds with floating aquatic plants.

    PubMed

    Kirzhner, F; Zimmels, Y

    2006-08-01

    The purpose of this paper is to estimate the evaporation rate in the purification of wastewater by aquatic plants with aeration. Evaporation of surface water is important in dewatering processes. In particular, this is true in arid climates, where evaporation rates are high. Aeration is known to enhance the wastewater purification process, but it increases concurrently the water evaporation rates. Evaporation and evapotranspiration rates were tested under field and laboratory conditions. Batch experiments were performed to study the levels of evaporation and evapotranspiration in free-water-surface, aquatic-plant systems. The experiments verified that, in these systems, the rate of evaporation increased as a result of aeration in the presence and absence of the aquatic plants. The evaporation rates resulting from aeration were found to be significant in the water balance governing the purification process. A preliminary model for description of the effect of rising air bubbles on the transport of water vapors was formulated. It is shown that aeration may account for a significant part of water losses that include surface evaporation. PMID:17059143

  13. 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. PMID:25150973

  14. Observations on anopheline breeding in relation to aquatic plants in different breeding habitats of Kheda (Gujarat).

    PubMed

    Kant, Rajni; Srivastava, H C

    2004-09-01

    Water bodies infested with aquatic vegetations may pose problems in mosquito control through bio-environmental methods. Paucity of information pertaining to association of mosquito breeding with aquatic vegetation was the basis for present investigation. The mosquito breeding sites infested with solitary/dominating plant community viz., Eichhornia crassipes, Ipomoea aquatica, Hydrilla verticillata, Nymphea neuchali, Trapa bispinosa, Lemna paucicostata, Trachelomonas spp., Azolla pinnata, Algae spp. and Cynodon dactylon were selected for the study. The investigation revealed that breeding of eleven anopheline species was associated with Eichhornia in different habitats followed by Hydrilla, algae and Cynodon (8 each), Ipomoea and Trapa (6), Lemna. and Nymphea (5), Azolla and Trachelomonas (4). An. subpictus was associated with all types of vegetation. An. annularis, An. nigerrimus and An. barbirostris were associated with nine plant species. An. culicifacies, the principal malaria vector was found breeding in association with seven aquatic plants and showed strong association with Cynodon, Hydrilla and algae. The species diversity in habitats infested with Hydrilla, algae and Cynodon seems to be most favourable for the breeding of An. culicifacies. It is suggested that thinning or removal of such vegetations at regular interval may help to reduce vector population and enhance the efficacy of biological control agents particularly the larvivorous fishes in such habitats. PMID:16509256

  15. 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. PMID:22319874

  16. The Mitochondrial Genome of an Aquatic Plant, Spirodela polyrhiza

    PubMed Central

    Wang, Wenqin; Wu, Yongrui; Messing, Joachim

    2012-01-01

    Background Spirodela polyrhiza is a species of the order Alismatales, which represent the basal lineage of monocots with more ancestral features than the Poales. Its complete sequence of the mitochondrial (mt) genome could provide clues for the understanding of the evolution of mt genomes in plant. Methods Spirodela polyrhiza mt genome was sequenced from total genomic DNA without physical separation of chloroplast and nuclear DNA using the SOLiD platform. Using a genome copy number sensitive assembly algorithm, the mt genome was successfully assembled. Gap closure and accuracy was determined with PCR products sequenced with the dideoxy method. Conclusions This is the most compact monocot mitochondrial genome with 228,493 bp. A total of 57 genes encode 35 known proteins, 3 ribosomal RNAs, and 19 tRNAs that recognize 15 amino acids. There are about 600 RNA editing sites predicted and three lineage specific protein-coding-gene losses. The mitochondrial genes, pseudogenes, and other hypothetical genes (ORFs) cover 71,783 bp (31.0%) of the genome. Imported plastid DNA accounts for an additional 9,295 bp (4.1%) of the mitochondrial DNA. Absence of transposable element sequences suggests that very few nuclear sequences have migrated into Spirodela mtDNA. Phylogenetic analysis of conserved protein-coding genes suggests that Spirodela shares the common ancestor with other monocots, but there is no obvious synteny between Spirodela and rice mtDNAs. After eliminating genes, introns, ORFs, and plastid-derived DNA, nearly four-fifths of the Spirodela mitochondrial genome is of unknown origin and function. Although it contains a similar chloroplast DNA content and range of RNA editing as other monocots, it is void of nuclear insertions, active gene loss, and comprises large regions of sequences of unknown origin in non-coding regions. Moreover, the lack of synteny with known mitochondrial genomic sequences shed new light on the early evolution of monocot mitochondrial genomes

  17. 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 ...

  18. Landfill impacts on aquatic plant communities and tissue metal levels at Indiana Dunes National Lakeshore

    SciTech Connect

    Stewart, P.M.; Scribailo, R.W.

    1995-12-31

    One important environmental issue facing Northwest Indiana and park management at Indiana Dunes National Lakeshore (INOU) is the contamination of water, sediment and biota by persistent toxic substances. Aquatic plant communities were used to evaluate the water/organismal quality of the Grand Calumet Lagoons and two dunal ponds (pannes) at Gary, Indiana, which are partially located in the Miller Woods Unit of INDU. The lagoon is divided into several areas, the USX Lagoon is located between sections of a large industrial landfill (steel slag and other material). The Marquette Lagoon is located further away from the landfill and tends to be upgradient from the landfill. The West Panne (WP) is located next to the landfill, while the East Panne (EP) is separated from the landfill and the WP by a high dune ridge. Plant populations shift toward fewer submergent aquatics, with a higher abundance of tolerant taxa in the western section of the USX Lagoon. These differences are supported by cluster analysis. Heavy metals in root tissue of Scirpus americanus and other plant species from the pannes were significantly higher than those found in shoots. Shoot tissue metal levels in plants collected from the lagoons were higher than root tissue metal levels. The WP site has the most elevated tissue metal levels for most metals assayed, while the EP site shows similar contaminant levels. The plant distributions observed and tissue metal concentrations measured suggest that INDU`s aquatic plant community has been affected by the industrial landfill and that there exists a hydrological connection between the ponds.

  19. 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

  20. 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.

  1. 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. PMID:26939740

  2. 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. )

    1993-01-01

    In this follow-up study, the authors compared the actual effects of the three complete ethanol plants on aquatic and terrestrial resources with the effects predicted in the NEPA environmental assessments (EAs). They based their comparative evaluations on reviews and analyses of existing data and information, interviews with plant, state, and local government personnel, and site and facility inspections. They found that (1) the plants as completed differed considerably in important respects from the proposed designs considerably in important respects from the proposed designs evaluated in the EAs; (2) several key source terms provided by the applicants were inaccurate; (3) most, but significantly, not all, mitigation measures described in the EAs were implemented; (4) external environmental changes independent of the plants affected the nature and degree of some impacts; and (5) although impacts to aquatic and terrestrial resources for which data were adequate for analysis generally occurred as predicted, a few impacts not anticipated in the EAs were identified. These included adverse effects of wastewaters on a municipal treatment plant with resulting temporary effects on the receiving stream, and unforeseen habitat loss due to vegetation removal (failure to implement planned mitigation) and barge terminal construction.

  3. Ubiquitous Water-Soluble Molecules in Aquatic Plant Exudates Determine Specific Insect Attraction

    PubMed Central

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

    2008-01-01

    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. PMID:18841203

  4. 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. PMID:27327439

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

    PubMed Central

    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. PMID:27327439

  6. 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

  7. 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.

  8. 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.

  9. 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

  10. 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.

  11. 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.

  12. 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.

  13. 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

  14. A quantitative and qualitative comparison of aquatic and terrestrial plant lignin phenols: Critical information for paleoecological reconstructions

    NASA Astrophysics Data System (ADS)

    Thomas, E. K.; Gao, L.; Huang, Y.

    2009-12-01

    Currently, lignin phenols are used in marine and lacustrine ecosystems as proxies for terrestrial vegetation inputs. Lignins are found in all vascular plants, where they play a crucial role in conduction of water, nutrients and photosynthates through the vascular system, and where they provide structural support. Furthermore, different types of lignin phenols are found in specific types of vegetation (e.g., both syringyl and vanillyl phenols are in angiosperm wood, but only vanillyl phenols are in gymnosperm wood). The ratio of lignin phenols (e.g. syringyl:vanillyl) is indicative of the type of plant from which the lignin phenols were derived. Studies that examine lignin phenols in sedimentary archives assume that lignin phenols are derived solely from terrestrial plants, and changes in the types of lignin phenols are therefore assumed to mark changes in terrestrial vegetation. These assumptions may be flawed, however, because many aquatic plants, including those that are submerged, are vascular, yet little is known about the type and concentration of lignin phenols present in aquatic vascular plants. This knowledge is imperative to the success of paleoecological studies that utilize lignin phenols as a geochemical proxy for terrestrial vegetation. Furthermore, lignin phenols may be important targets for compound-specific radiocarbon dating, which is useful when suitable macrofossils are unavailable. Knowing the origin of the molecules used for radiocarbon dating, however, (i.e. whether they are terrestrial or aquatic) is critical to obtaining meaningful chronologies. We isolated and analyzed lignin phenol monomers from different types of aquatic vascular plants. All plants analyzed are angiosperms, but they occupy different niches in aquatic plant communities: floating, emergent and submergent. We also analyzed different parts of aquatic plants (i.e., stems and leaves). We found lignin phenols in all aquatic species that we analyzed, which highlights the need for

  15. 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.

  16. 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.

  17. Metal adsorption by quasi cellulose xanthogenates derived from aquatic and terrestrial plant materials.

    PubMed

    Zhou, Wenbing; Ge, Xuan; Zhu, Duanwei; Langdon, Alan; Deng, Li; Hua, Yumei; Zhao, Jianwei

    2011-02-01

    The FTIR spectra, SEM-EDXA and copper adsorption capacities of the raw plant materials, alkali-treated straws and cellulose xanthogenate derivatives of Eichhornia crassipes shoot, rape straw and corn stalk were investigated. FTIR spectra indicated that of the three plant materials, the aquatic biomass of E. crassipes shoot contained more OH and CO groups which accounted for the higher Cu(2+) adsorption capacities of the raw and alkali treated plant material. SEM-EDXA indicated the incorporation of sulphur and magnesium in the cellulose xanthogenate. The Cu(2+) adsorption capacities of the xanthogenates increased with their magnesium and sulphur contents. However more copper was adsorbed than that can be explained by exchange of copper with magnesium. Precipitation may contribute to the enhanced uptake of copper by the cellulose xanthogenate. PMID:21123055

  18. Extraction of /sup 14/C-labeled photosynthate from aquatic plants with dimethyl sulfoxide (DMSO)

    SciTech Connect

    Filbin, G.J.; Hough, R.A.

    1984-03-01

    DMSO was tested as a solvent to extract /sup 14/C-labeled photosynthate from three species of aquatic plants in photosynthesis measurements and compared with the dry oxidation method for plant radioassay. Extraction of ca. 300 mg of fresh or rehydrated dry plant tissue samples in 10 ml of reagent-grade DMSO for 8h at 65/sup 0/C resulted in a stable, nonviscous solution with excellent liquid scintillation counting characteristics. Extraction efficiency was in the range of 96-99% of fixed /sup 14/C, and precision was comparable to, or better than, that obtained with dry oxidation. The method is simple and inexpensive, and for fresh tissue the same sample extracts can be used for chlorophyll analyses.

  19. 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

  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. PMID:11554485

  1. 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

  2. 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.

  3. 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). PMID:26380667

  4. 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. PMID:17354448

  5. 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%. PMID:25818110

  6. 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.

  7. 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. PMID:20529068

  8. 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. PMID:15642713

  9. 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. PMID:25634365

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

    SciTech Connect

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

    1993-06-01

    Compared were concentrations of Al,Cd,Ca,Cu,Fe,Pb,Mg,Mn,Hg,Ni,P, and Zn 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 concentration of metals in water were not greatly affected by pH. None of the metal concentrations in water 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 seems 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..

  11. 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.

  12. 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. PMID:26757140

  13. 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.

  14. 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

  15. 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...

  16. 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...

  17. 33 CFR Appendix C to Part 273 - Information Requirements for Aquatic Plant Control Program Environmental Impact Statements

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 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....

  18. 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

    ... 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....

  19. 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

    ... 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....

  20. Responses of selected aquatic biota to thermal discharges from Cumberland Steam-Electric Plant: Barkley Reservoir, Tennessee, 1978 and 1979

    SciTech Connect

    Craven, T.M.; Dycus, D.L.; Wade, D.C.

    1983-08-01

    The extent and degree of exposure of aquatic biota to the thermal plume from Cumberland Steam-Electric Plant (CUF) depends upon several factors, including temperature and volume of water discharged from the plant into the Cumberland River and river flow rates. During periods of discharging large volumes of heated water (maximum plant operation) to the Cumberland River under low flow conditions, maximum exposure would occur, influencing aquatic biota both up- and downstream of the plant. Results of this study, made during periods of maximum potential thermal stress (July to September) under varying flow and reservoir conditions, show thermal discharges from TVA's Cumberland Plant are not adversely impacting local aquatic communities studied. Differences in population structures and standing crops of plankton and macroinvertebrates were more related to reservoir conditions (i.e., suspended solids) than to operation of the plant. Community numbers and indices of health (as measured) downstream of the plant were usually as high as or higher than in upstream (unaffected) areas. Although several isolated effects occurred immediately downstream of the thermal discharge, no permanent alterations were documented on the local Cumberland River floral and faunal communities. 101 references, 25 figures, 24 tables.

  1. 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

  2. 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. PMID:26539039

  3. Microhistological characteristics of selected aquatic plants of Florida, with techniques for the study of manatee food habits

    USGS Publications Warehouse

    Hurst, L.A.; Beck, C.A.

    1988-01-01

    This study was initiated in 1978 to develop a technique of identifying and quantifying the digestive tract contents of Florida manatees (Trichechus manatus latirostris) and to serve as a manual for the identification and analysis of ingesta collected from manatee carcasses salvaged in Florida. This report includes key microhistological characters found useful in identifying fragments of 83 plant species and three invertebrate groups. Many species of aquatic and wetland plants and invertebrates are available to manatees in Florida as potential foods.

  4. 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. PMID:27055891

  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. 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. PMID:26515993

  7. 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.

  8. 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. PMID:26360459

  9. 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...

  10. 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. PMID:26143200

  11. 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. PMID:25940213

  12. 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.

  13. 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. PMID:21327536

  14. 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.

  15. 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.

  16. 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. PMID:27023818

  17. 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. PMID:24925182

  18. Monitoring and assessment of mercury pollution in the vicinity of a chloralkali plant. IV. Bioconcentration of mercury in in situ aquatic and terrestrial plants at Ganjam, India.

    PubMed

    Lenka, M; Panda, K K; Panda, B B

    1992-02-01

    In situ aquatic and terrestrial plants including a few vegetable and crop plants growing in and around a chloralkali plant at Ganjam, India were analyzed for concentrations of root and shoot mercury. The aquatic plants found to bioconcentrate mercury to different degrees included Marsilea spp., Spirodela polyrhiza, Jussiea repens, Paspalum scrobiculatam, Pistia stratiotes, Eichhornia crassipes, Hygrophila schulli, Monochoria hastata and Bacopa monniera. Among wild terrestrial plants Chloris barbata, Cynodon dactylon, Cyperus rotundus and Croton bonplandianum were found growing on heavily contaminated soil containing mercury as high as 557 mg/kg. Analysis of mercury in root and shoot of these plants in relation to the mercury levels in soil indicated a significant correlation between soil and plant mercury with the exception of C. bonplandianum. Furthermore, the tolerance to mercury toxicity was highest with C. barbata followed by C. dactylon and C. rotundus, in that order. The rice plants analyzed from the surrounding agricultural fields did not show any significant levels of bioconcentrated mercury. Of the different vegetables grown in a contaminated kitchen garden with mercury level at 8.91 mg/kg, the two leafy vegetables, namely cabbage (Brassica oleracea) and amaranthus (Amaranthus oleraceous), were found to bioconcentrate mercury at statistically significant levels. The overall study indicates that the mercury pollution is very much localized to the specific sites in the vicinity of the chloralkali plant. PMID:1536599

  19. 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.)

  20. 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.

  1. Genome size as a key to evolutionary complex aquatic plants: polyploidy and hybridization in Callitriche (Plantaginaceae).

    PubMed

    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:25211149

  2. 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

  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. PMID:16177926

  4. 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

  5. [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. PMID:22946164

  6. 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. PMID:22820614

  7. 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. PMID:25129834

  8. 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

  9. 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.

  10. 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. PMID:25077615

  11. 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

  12. 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

  13. 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. PMID:26797943

  14. Captive bubble and sessile drop surface characterization of a submerged aquatic plant, Hydrilla verticillata

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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...

  15. Use of Hyperspectral Remote Sensing to Evaluate Efficacy of Aquatic Plant Management

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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 ...

  16. 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...

  17. 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.

  18. 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

  19. 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. PMID:27149077

  20. 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

  1. 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. PMID:22126662

  2. [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. PMID:23113334

  3. 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.

  4. Morphotype-specific effector functions of Cryptococcus neoformans PUM1

    PubMed Central

    Kaur, Jan Naseer; Panepinto, John C.

    2016-01-01

    The basidiomycete fungal pathogen Cryptococcus neoformans requires the PUF protein, Pum1, for hyphal morphogenesis during sexual development. In this study we found that Pum1 was auto-repressive under growth as yeast, but that auto-repression was relieved during filamentous growth through utilization of an alternative transcription start site driven by the master filamentation regulator Znf2. In addition, Pum1 was required to stabilize the ZNF2 mRNA through an indirect mechanism suggesting that Znf2 and Pum1 each positively regulate the expression of the other to achieve the filamentous morphotype required for sexual development in Cryptococcus. PMID:27008977

  5. Central pattern generator for vocalization: Is there a vertebrate morphotype?

    PubMed Central

    Bass, Andrew H.

    2014-01-01

    Animals that generate acoustic signals for social communication are faced with two essential tasks: generate a temporally precise signal and inform the auditory system about the occurrence of one’s own sonic signal. Recent studies of sound producing fishes delineate a hindbrain network comprised of anatomically distinct compartments coding equally distinct neurophysiological properties that allow an organism to meet these behavioral demands. A set of neural characters comprising a vocal-sonic central pattern generator (CPG) morphotype is proposed for fishes and tetrapods that shares evolutionary developmental origins with pectoral appendage motor systems. PMID:25050813

  6. 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. PMID:24146323

  7. 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. PMID:11205536

  8. 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

  9. 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

    2014-02-01

    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

  10. 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

  11. Endobacterial morphotypes in nudibranch cerata tips: a SEM analysis

    NASA Astrophysics Data System (ADS)

    Schuett, Christian; Doepke, Hilke

    2013-06-01

    The SEM investigation of nudibranch cerata material exhibits endobacterial morphotypes found in 12 out of 13 species tested: Aeolidia papillosa, Berghia caerulescens, Coryphella brownii, Coryphella lineata, Coryphella verrucosa, Cuthona amoena, Facelina coronata, Flabellina pedata, Dendronotus frondosus, Doto coronata, Tritonia plebeia and Janolus cristatus. Endobacteria could not be detected inside Tritonia hombergi. Endobacterial morphology found inside nudibranch species was compared to bacterial morphotypes detected earlier in tentacles of cnidarian species. SEM micrographs show endobacterial analogy among nudibranch species, but also similarity to cnidarian endobacteria investigated earlier. Of course, morphological data of microbes do not allow their identification. However, since most of these nudibranch species prey on cnidaria, it cannot be excluded that many of the endobacteria detected inside nudibranch species may originate from their cnidarian prey. Our previous data describing genetic affiliation of endobacteria from nudibranchian and cnidarian species support this assumption. Dominant coccoid endobacteria mostly exhibit smooth surface and are tightly packed as aggregates and/or wrapped in envelopes. Such bacterial aggregate type has been described previously in tentacles of the cnidarian species Sagartia elegans. Similar coccoid bacteria, lacking envelopes were also found in other nudibranch species. A different type of coccoid bacteria, characterized by a rough surface, was detected inside cerata of the nudibranch species Berghia caerulescens, and surprisingly, inside tentacles of the cnidarian species Tubularia indivisa. In contrast to cnidarian endobacteria, rod-shaped microorganisms are largely absent in nudibranch cerata.

  12. 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.

  13. Integument and defence in larva and prepupa of a sawfly living on a semi-aquatic plant.

    PubMed

    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. PMID:23183874

  14. 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

  15. 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

  16. 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

  17. 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. PMID:19455397

  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. PMID:24530727

  19. 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. PMID:15656166

  20. Responses of selected aquatic biota to thermal discharges from Cumberland Steam-Electric Plant: Barkley Reservoir, Tennessee, 1978 and 1979. Appendices

    SciTech Connect

    Craven, T.M.; Dycus, D.L.; Wade, D.C.

    1983-08-01

    The extent and degree of exposure of aquatic biota to the thermal plume from Cumberland Steam-Electric Plant (CUF) depends upon several factors, including temperature and volume of water discharged from the plant into the Cumberland River and river flow rates. During periods of discharging large volumes of heated water (maximum plant operation) to the Cumberland River under low flow conditions, maximum exposure would occur, influencing aquatic biota both up- and downstream of the plant. Results of this study, made during periods of maximum potential thermal stress (July to September) under varying flow and reservoir conditions, show thermal discharges from TVA's Cumberland Plant are not adversely impacting local aquatic communities studied. Differences in population structures and standing crops of plankton and macroinvertebrates were more related to reservoir conditions (i.e., suspended solids) than to operation of the plant. Community numbers and indices of health (as measured) downstream of the plant were usually as high as or higher than in upstream (unaffected) areas. Although several isolated effects occurred immediately downstream of the thermal discharge, no permanent alterations were documented on the local Cumberland River floral and faunal communities. This volume contains data on water quality, temperatures, river flow, plankton composition and biomass, and macrophyte species.

  1. Burkholderia pseudomallei Colony Morphotypes Show a Synchronized Metabolic Pattern after Acute Infection

    PubMed Central

    Steinmetz, Ivo; Lalk, Michael

    2016-01-01

    Background Burkholderia pseudomallei is a water and soil bacterium and the causative agent of melioidosis. A characteristic feature of this bacterium is the formation of different colony morphologies which can be isolated from environmental samples as well as from clinical samples, but can also be induced in vitro. Previous studies indicate that morphotypes can differ in a number of characteristics such as resistance to oxidative stress, cellular adhesion and intracellular replication. Yet the metabolic features of B. pseudomallei and its different morphotypes have not been examined in detail so far. Therefore, this study aimed to characterize the exometabolome of B. pseudomallei morphotypes and the impact of acute infection on their metabolic characteristics. Methods and Principal Findings We applied nuclear magnetic resonance spectroscopy (1H-NMR) in a metabolic footprint approach to compare nutrition uptake and metabolite secretion of starvation induced morphotypes of the B. pseudomallei strains K96243 and E8. We observed gluconate production and uptake in all morphotype cultures. Our study also revealed that among all morphotypes amino acids could be classified with regard to their fast and slow consumption. In addition to these shared metabolic features, the morphotypes varied highly in amino acid uptake profiles, secretion of branched chain amino acid metabolites and carbon utilization. After intracellular passage in vitro or murine acute infection in vivo, we observed a switch of the various morphotypes towards a single morphotype and a synchronization of nutrient uptake and metabolite secretion. Conclusion To our knowledge, this study provides first insights into the basic metabolism of B. pseudomallei and its colony morphotypes. Furthermore, our data suggest, that acute infection leads to the synchronization of B. pseudomallei colony morphology and metabolism through yet unknown host signals and bacterial mechanisms. PMID:26943908

  2. 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. PMID:25277712

  3. Evolution of cyanobacterial morphotypes: Taxa required for improved phylogenomic approaches.

    PubMed

    Schirrmeister, Bettina E; Anisimova, Maria; Antonelli, Alexandre; Bagheri, Homayoun C

    2011-07-01

    Within prokaryotes cyanobacteria represent one of the oldest and morphologically most diverse phyla on Earth. The rise of oxygen levels in the atmosphere 2.32-2.45 billion years ago is assigned to the photosynthetic activity of ancestors from this phylum. Subsequently cyanobacteria were able to adapt to various habitats evolving a comprehensive set of different morphotypes. In a recent study we showed that this evolution is not a gradual transition from simple unicellular to more complex multicellular forms as often assumed. Instead complexity was lost several times and regained at least once. An understanding of the genetic basis of these transitions would be further strengthened by phylogenomic approaches. However, considering that new methods for phylogenomic analyses are emerging, it is unfortunate that genomes available today are comprised of an unbalanced sampling of taxa. We propose avenues to remedy this by identifying taxa that would improve the representation of phylogenetic diversity in this phylum. PMID:21966561

  4. Acidic environments induce differentiation of Proteus mirabilis into swarmer morphotypes.

    PubMed

    Fujihara, Masatoshi; Obara, Hisato; Watanabe, Yusaku; Ono, Hisaya K; Sasaki, Jun; Goryo, Masanobu; Harasawa, Ryô

    2011-07-01

    Although swarmer morphotypes of Proteus mirabilis have long been considered to result from surfaced-induced differentiation, the present findings show that, in broth medium containing urea, acidic conditions transform some swimmer cells into elongated swarmer cells. This study has also demonstrates that P. mirabilis cells grown in acidic broth medium containing urea enhance virulence factors such as flagella production and cytotoxicity to human bladder carcinoma cell line T24, though no significant difference in urease activity under different pH conditions was found. Since there is little published data on the behavior of P. mirabilis at various hydrogen-ion concentrations, the present study may clarify aspects of cellular differentiation of P. mirabilis in patients at risk of struvite formation due to infection with urease-producing bacteria, as well as in some animals with acidic or alkaline urine. PMID:21707738

  5. 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. PMID:14750429

  6. Limited Genetic Connectivity between Gorgonian Morphotypes along a Depth Gradient

    PubMed Central

    Gori, Andrea; Lopez-González, Pablo; Bramanti, Lorenzo; Rossi, Sergio; Gili, Josep-Maria; Abbiati, Marco

    2016-01-01

    Gorgonian species show a high morphological variability in relation to the environment in which they live. In coastal areas, parameters such as temperature, light, currents, and food availability vary significantly with depth, potentially affecting morphology of the colonies and the structure of the populations, as well as their connectivity patterns. In tropical seas, the existence of connectivity between shallow and deep populations supported the hypothesis that the deep coral reefs could potentially act as (reproductive) refugia fostering re-colonization of shallow areas after mortality events. Moreover, this hypothesis is not so clear accepted in temperate seas. Eunicella singularis is one of the most common gorgonian species in Northwestern Mediterranean Sea, playing an important role as ecosystem engineer by providing biomass and complexity to the coralligenous habitats. It has a wide bathymetric distribution ranging from about 10 m to 100 m. Two depth-related morphotypes have been identified, differing in colony morphology, sclerite size and shape, and occurrence of symbiotic algae, but not in mitochondrial DNA haplotypes. In the present study the genetic structure of E. singularis populations along a horizontal and bathymetric gradient was assessed using microsatellites and ITS1 sequences. Restricted gene flow was found at 30–40 m depth between the two Eunicella morphotypes. Conversely, no genetic structuring has been found among shallow water populations within a spatial scale of ten kilometers. The break in gene flow between shallow and deep populations contributes to explain the morphological variability observed at different depths. Moreover, the limited vertical connectivity hinted that the refugia hypothesis does not apply to E. singularis. Re-colonization of shallow water populations, occasionally affected by mass mortality events, should then be mainly fueled by larvae from other shallow water populations. PMID:27490900

  7. Distinguishing Morphotypes of Foraminifera Orbulina Universa Using Shell Morphometrics

    NASA Astrophysics Data System (ADS)

    Marshall, B. J.; Thunell, R.

    2014-12-01

    Several recent genetic studies have revealed that many morphologically defined planktonic foraminiferal species contain multiple distinct cryptic or pseudocryptic genetic variants. In some cases, such as with the genetic variants of Globigerinoides ruber, past taxonomic "lumping" may be easily revised within the framework of the morphospecies concept. However, some planktonic foraminiferal cryptic species are not easily differentiated from one another based on identifiable morphological differences, as is the case with Orbulina universa cryptic species (Morard et al., 2009). Based on recent findings, it is believed that several of these O. universa cryptic species differ in their habitat preferences (Darling et al., 1999,2000; de Vargas et al., 1999, 2001), and the lumping of these cryptic species could possibly account for a significant amount of the noise observed in various paleoclimate records derived from this species (Kucera and Darling, 2002). The current study uses foraminiferal morphometrics (area density, Marshall et al., 2013, thickness and weight-diameter realtionships) to identify distinct groupings of individual Orbulina universa specimens collected from sediment trap samples in the Cariaco Basin, Venezuela. The study reveals three distinct groups of individuals, varying in their test thicknesses and pore space distribution, which likely correspond to the previously identified cryptic species of O. universa. We find significant differences in the isotopic compositions of these groupings - suggesting that the identified morphotypes differ in their habitat preferences. These morphotypes also exhibit different relationships with the measured hydrographic parameters and their relative distribution can be linked to changes in upwelling and non-upwelling hydrographic regimes. We agree with the results of previous studies that suggest different cryptic species should not be treated as ecophenotypic variants and need to be distinguished from one another

  8. Limited Genetic Connectivity between Gorgonian Morphotypes along a Depth Gradient.

    PubMed

    Costantini, Federica; Gori, Andrea; Lopez-González, Pablo; Bramanti, Lorenzo; Rossi, Sergio; Gili, Josep-Maria; Abbiati, Marco

    2016-01-01

    Gorgonian species show a high morphological variability in relation to the environment in which they live. In coastal areas, parameters such as temperature, light, currents, and food availability vary significantly with depth, potentially affecting morphology of the colonies and the structure of the populations, as well as their connectivity patterns. In tropical seas, the existence of connectivity between shallow and deep populations supported the hypothesis that the deep coral reefs could potentially act as (reproductive) refugia fostering re-colonization of shallow areas after mortality events. Moreover, this hypothesis is not so clear accepted in temperate seas. Eunicella singularis is one of the most common gorgonian species in Northwestern Mediterranean Sea, playing an important role as ecosystem engineer by providing biomass and complexity to the coralligenous habitats. It has a wide bathymetric distribution ranging from about 10 m to 100 m. Two depth-related morphotypes have been identified, differing in colony morphology, sclerite size and shape, and occurrence of symbiotic algae, but not in mitochondrial DNA haplotypes. In the present study the genetic structure of E. singularis populations along a horizontal and bathymetric gradient was assessed using microsatellites and ITS1 sequences. Restricted gene flow was found at 30-40 m depth between the two Eunicella morphotypes. Conversely, no genetic structuring has been found among shallow water populations within a spatial scale of ten kilometers. The break in gene flow between shallow and deep populations contributes to explain the morphological variability observed at different depths. Moreover, the limited vertical connectivity hinted that the refugia hypothesis does not apply to E. singularis. Re-colonization of shallow water populations, occasionally affected by mass mortality events, should then be mainly fueled by larvae from other shallow water populations. PMID:27490900

  9. 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

  10. 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

  11. 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.

  12. 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

    2016-01-01

    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

  13. 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

  14. Impacts of water development on aquatic macroinvertebrates, amphibians, and plants in wetlands of a semi-arid landscape

    USGS Publications Warehouse

    Euliss, N.H., Jr.; Mushet, D.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 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, northern leopard frog, plains spadefoot, Woodhouse's toad, and tiger salamander. 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.

  15. Drag forces on aquatic plants in nonlinear random waves plus current

    NASA Astrophysics Data System (ADS)

    Henry, Pierre-Yves; Myrhaug, Dag; Aberle, Jochen

    2015-11-01

    Plant-flow interactions are characterised by an assemblage of processes acting at different temporal and spatial scales. In order to mathematically characterise these interactions, such processes have to be parameterised given some simplifications. Typically, drag coefficients are derived from experiments to characterise the plant reconfiguration and wave energy dissipation processes. By reviewing the different plant drag coefficients CD valid in oscillatory flows, this study first highlights the lack of normalisation of the different existing CD formulations and identifies possibilities for a standardisation of the formulations for oscillatory and steady flows. Then, by taking into account the wave crest height distribution of a sea state condition, this study further develops a stochastic method to compute the expected wave induced forces on a plant in linear/nonlinear random waves plus current based on two different CD formulations for waves alone and waves plus current. This method improves the characterisation of the stochastic plant-flow interactions by allowing the calculation of expected values under different random wave plus currents conditions. Results are compared to a classic deterministic approach and some differences are identified, calling for further investigations against experimental datasets. Based on the appropriate CD formulations, this study finally revealed that wave nonlinearities have a significant effect on expected wave forces for a higher wave activity, and that in presence of an increasing current, the effect of wave nonlinearities decreases while the expected wave forces increase.

  16. Effect of Hirschmanniella caudacrena on the Submersed Aquatic Plants Ceratophyllum demersum and Hydrilla verticillata.

    PubMed

    Gerber, K; Smart, G C

    1987-10-01

    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. Phytotoxicity of oil sands naphthenic acids and dissipation from systems planted with emergent aquatic macrophytes.

    PubMed

    Armstrong, Sarah A; Headley, John V; Peru, Kerry M; Germida, James J

    2008-01-01

    Differences in dissipation and phytotoxicity were measured for two naphthenic acid mixtures in hydroponically grown emergent macrophytes (Typha latifolia, Phragmites australis, and Scirpus acutus). One of the naphthenic acid (NA) mixtures was extracted from tailings pond water of an oil sands operation in Fort McMurray, Alberta, Canada. The other mixture was a commercially available NA mixture. While the oil sands NA mixture was less phytotoxic to wetland plants compared to the commercially available NA mixture, they were not sequestered by wetland plants like their commercial NA counterparts. The small loss of commercial NAs from the spiked hydroponic system appeared to be selective and dependant on the specific NA compound. The results of this study indicate that plants alone may not mitigate NAs from oil sands tailings pond water. In addition, caution should be taken when making predictions on the environmental fate of oil sands naphthenic acids when using commercial NAs as surrogates. PMID:18161556

  18. 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.

  19. 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

  20. 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. PMID:22970206

  1. Screening of aquatic and wetland plant species for phytoremediation of explosives-contaminated groundwater from the Iowa Army Ammunition Plant.

    PubMed

    Best, E P; Zappi, M E; Fredrickson, H L; Sprecher, S L; Larson, S L; Ochman, M

    1997-11-21

    The results of this study indicate that the presence of plants did enhance TNT and TNB removal from IAAP groundwater. Most effective at 25 degrees C were reed canary grass, coontail and pondweed. Groundwater and plant tissue analyses indicate that in presence of the plants tested TNT is degraded to reduced by-products and to other metabolites that were not analyzed. TNT removal was best modeled using first order kinetics, with rate constants at 25 degrees C incubations ranging from 0.038 microgram L-1 h-1 for reed canary grass to 0.012 microgram L-1 h-1 for parrot-feather. These kinetics predict hydraulic retention times (HRTs) ranging from 4.9 days to 19.8 days to reach a TNT concentration of 2 micrograms L-1. Decreasing incubation temperature to 10 degrees C affected reed canary grass more than parrot-feather, increasing estimated HRTs by factors of four and two, respectively. The plant species tested showed a far lower potential for RDX removal from the IAAP groundwater. Most effective at 25 degrees C were reed canary grass and fox sedge. Analyses of plant material indicated the presence of RDX in under-water plant portions and in aerial plant portions, and RDX accumulation in the latter. RDX removal was best modeled using zero order kinetics, with rate constants for the 25 degrees C incubation ranging from 13.45 micrograms L-1 h-1 for reed canary grass to no removal in four species. Based on these kinetics, estimated HRTs to reach 2 micrograms L-1 RDX increased from 39 days. Decreasing the temperature to 10 degrees C increased HRT 24-fold for reed canary grass. By using the biomass-normalized K value, submersed plants are identified as having the highest explosives-removing activity (microgram explosive L-1 h-1 g DW-1). However, biomass production of submersed plants is normally five to ten times less than that of emergent plants per unit area, and, thus, in plant selection for wetland construction, both, explosives removal potential and biomass production are

  2. Genetic Inheritance of Female and Male Morphotypes in Giant Freshwater Prawn Macrobrachium rosenbergii

    PubMed Central

    2014-01-01

    Giant freshwater prawn (GFP) Macrobrachium rosenbergii is unique with males categorized in five different morphotypes (small claw, orange claw, blue claw, old blue claw and no claw males) and females in three reproductive statuses (mature ovary, berried and spawned females). In the present study we examined genetic inheritance of female and male morphotypes, their body weights and genetic associations between morphotypes and body traits. Restricted maximum likelihood fitting a multi-trait animal model was performed on a total of 21,459 body records collected over five generations in a GFP population selected for high growth rate. The estimates of variance components showed that there were substantial differences in additive genetic variance in body weight between male morphotypes. The low and significantly different from one genetic correlations between the expressions of body weight in male morphotypes also suggest that these traits should be treated as genetically different traits in selective breeding programs. By contrast, body weights of female types are essentially the same characters as indicated by the high genetic correlations between homologous trait expressions. In addition to body weight, male morphotypes and female reproductive statuses were treated as traits in themselves and were analysed as binary observations using animal and sire linear mixed models, and logit and probit threshold models. The estimates of heritability back-transformed from the liability scale were in good agreement with those obtained from linear mixed models, ranging from 0.02 to 0.43 for male morphotypes and 0.06 to 0.10 for female types. The genetic correlations among male morphoptypes were generally favourable. Body weight showed negative genetic associations with SM (−0.96), whereas those of body weight with other male morphotypes were positive (0.25 to 0.76). Our results showed that there is existence of heritable (additive genetic) component for male morphotypes, giving

  3. 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

  4. 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. PMID:23967314

  5. 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

  6. 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. PMID:26946117

  7. 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.

  8. Characterizing subsurface complexity of aeolian morphotypes with georadar

    NASA Astrophysics Data System (ADS)

    Bentley, Andrew Phillip Keller

    Aeolian landforms are classified based on their plan morphology, which is a function of sediment transport volume, wind direction, and vegetation. In the case of compound landforms or two-dimensional exposures (outcrops), there is insufficient information for discriminating between 3D morphotypes (e.g., barchans vs. parabolic dunes). To characterize the dip-section architecture of near end-member morphologies (interacting barchans and sparsely vegetated parabolics), a series of axial transects were selected from >25 km of high-resolution (500 MHz) ground-penetrating radar (GPR) data from the gypsum dune field of White Sands National Monument, New Mexico. For dunes of comparable size (6-7 m high), a series of attributes were analyzed for unsaturated portions along the thickest (axial) radargram sections. Given the limitations in vertical resolution (7 cm in dry sand), the average measureable slipface thickness in barchans ranged between 10-22 cm, whereas parabolic slipfaces were thinner at 10-14 cm. High-amplitude diffractions produced by buried vegetation, semi-lithified pedestals, and bioturbation structures were rare within barchans (point-source diffraction density = 0.03/m2; hyperbolics per 1-m-wide cross-sectional area of the image), in contrast to a point-source density of 0.07/m2 in parabolics. An aeolian internal complexity threshold (pi) is proposed, which incorporates standardized scores of slipface thickness, point-source diffraction density, and continuity of major bounding surfaces at mesoscale range determined through semivariogram analysis. For the study region, these variables were sufficient for discriminating barchans (pi = -2.39 to -0.25; pib= -1.65) from parabolic (pi = 0.13 to 2.87; pip= 1.65) dunes. This threshold has the potential for differentiating dune morphotypes in areas where surface morphology is masked and for identifying compound landforms (e.g., a re-activated parabolic dune converted into a barchan in situ ). Ultimately

  9. Mineralized Remains of Morphotypes of Filamentous Cyanobacteria in Carbonaceous Meteorites

    NASA Technical Reports Server (NTRS)

    Hoover, Richard B.

    2005-01-01

    ) investigations of freshly fractured interior surfaces of carbonaceous meteorites, terrestrial rocks, and recent microbial extremophiles and filamentous cyanobacteria. These studies have resulted in the detection in a several carbonaceous meteorites of the mineralized remains of a wide variety of complex filamentous trichomic microorganisms. These embedded forms are consistent in size and microstructure with well-preserved morphotypes of mat- forming filamentous trichomic cyanobacteria and the degraded remains of microfibrils of cyanobacterial sheaths. We present the results of comparative imaging studies and EDAX elemental analyses of recent cyanobacteria (e.g. Calothrix, Oscillatoria, and Lyngbya) that are similar in size, morphology and microstructure to morphotypes found embedded in meteorites. EDAX elemental studies reveal that forms found in carbonaceous meteorites often have highly carbonized sheaths in close association with permineralized filaments, trichomes and microbial cells. Ratios of critical bioelements (C:O, C:N, C:P, and C:S) reveal dramatic differences between microfossils in Earth rocks and meteorites and in filaments, trichomes, hormogonia, and cells of recent cyanobacteria.

  10. 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.