Pond Weed Research Articles

<p><strong>A new name for extant <em>Potamogeton × mirabilis</em> (Potamogetonaceae)</strong></p>

The genus Potamogeton Linnaeus (1753: 126) is commonly called as pond weeds and they are the largest genera in the family Potamogetonaceae with about 88 species (POWO 2021). Furthermore the genus is noted for its high phenotypic plasticity and frequent hybridization that prompts impressive challenges in the delimitation and identification of species (Kaplan et al. 2009, 2013). A few instances of the homonymy among living and fossil monocots have been as of late settled by various workers (Turner 2014, Doweld 2016, 2018, Govaerts 2018, Kottaimuthu & Basu 2020). Recently we found that the extant hybrid Potamogeton × mirabilis Kaplan et al. (2009: 630) is an illegitimate later homonym according to Art.53.1. of ICN (Turland et al. 2018) because the name was already used by Kutuzkina (1957) to a fossil-species from Kyrgyzstan (formerly USSR). Hence a new replacement name is proposed for this nothospecies.

Determining distribution coefficients for low cost adsorbents

AbstractAs with other construction materials, coal fly ash contains trace metals that can leach into the natural environment. As part of a broader effort to encourage appropriate coal combustion product use in infrastructure applications (e.g., road construction, stabilization, and structural fill), this study evaluated traditional and low‐cost adsorbent alternatives for their capacity to attenuate trace metals. Batch sorption tests were used as a preliminary screen for a wide variety of low cost (e.g., steel byproducts, rubber dust, and compost) and innovative materials (e.g., kudzu, biofilm, and pond weed) as well as conventional materials (activated carbon, alumina, and zeolites). The removal rates were demonstrated in this study by observing the calculated distribution coefficient (Kd) which were determined using a program called MATLAB. Limestone and steel byproducts were found to be particularly effective with large Kd values of 15,740, 1,520, and 540 L kg−1 for cadmium, chromium, and selenium and, for ladle refractory and mill scale, Kd values of 3,910, 670, and 1,760 L kg−1 were observed. Among the three metals tested for this study, it was observed that most low cost and innovative materials removed cadmium quite efficiently; however, the removal of selenium and chromium depended on the substrate and prevailing pH. In general, these results suggest that alternative materials may have relevance in niche applications where leaching is a concern that can be addressed through enhanced attenuation capacity via blending or layering of adsorbents.

Urinary schistosomiasis outbreak in a community basic school, la Nkwantanang-Madina Municipality, Ghana-2016

Introduction : urinary schistosomiasis is a parasitic Neglected Tropical Disease caused by blood flukes called Schistosoma haematobium and characterized by terminal hematuria.School-aged children get infested through habits such as swimming and fishing in infested water bodies. Schistosomiasis is endemic in Ghana. On September 28, 2016, La Madina Nkwantanang Municipality (LaMNM) reported clusters of suspected schistosomiasis in a basic school. We investigated to determine the extent and risk factors of the outbreak and implement control and preventive measures. Methods : we screened all pupils with a questionnaire followed by testing urine of those with a history of hematuria. We conducted 14 case control study to determine the risk factors for schistosomiasis. A case of urinary schistosomiasis was any pupil from the affected school with Schistosoma ova identified in the urine. We interviewed case patients and their controls to obtain data on socio-demographic characteristics and their social play habits. We conducted an environmental assessment. Descriptive and inferential data analyses were done. Risk factors were assessed using adjusted odds ratio (AOR) and their corresponding 95% confidence intervals. Results : of 753 students, 81 case-patients were identified (attack rate 10.8%). Sex specific attack rates were 17.0% (68/401) for males and 3.7% (13/352) for females. Median age of case-patients was 13 years (IQR 11-14 years). Compared to controls, case-patients were more likely to be males [AOR=5.8 (CI=3.04; 11.96)]. After controlling for possible confounders, swimming in Silver land pond [AOR=9.0, 95%CI (2.18-33.55)] and swimming in Quotam pond [AOR=3.2, 95%CI (1.10-9.41)] were independent risk factors for contracting schistosomiasis. Conclusion : urinary schistosomiasis outbreak mainly affecting males occurred in LaMNM. Swimming in infested ponds was the major risk factor. Following our investigation, health education, mollusciciding and clearing of weeds in ponds, and preventive chemotherapy using Praziquantel were carried out.

Fractionation of Mercury in Water Hyacinth and Pondweed from Contaminated Area of Gold Mine Tailing

The ability of water hyacinth (WH) and pondweed (PW) to accumulate mercury from water in gold mine tailing area was studied. Experiments were carried out in the field conditions without using a model system. An approach for mercury fractionation according to its association with various types of biomolecules (water soluble compounds, oxygen-containing ligands such as polycarboxylic acids and cell wall components) was suggested. It is based on sequential extraction of mercury to recover different compounds according to the binding strength. In all cases for WH and PW, the most portion of mercury is bound to the cell wall (63–67 and 54–64 %, for WH and PW, respectively) that works as a physiological barriers and protects the plants from negative impact of mercury ions. An approach based on the ability of plants to extract elements from tailings drainage waters that are characterized by milder conditions in comparison with strongly acidic waste material was suggested. The highest BCF values (66,500 and 32,700 for WH and PW, respectively) were obtained for plants grown in natural stream. At low levels of mercury in water (C Hgwater = 0.01–0.05 ppb) typical for tailing solutions, translocation of the element from roots to shoots decreases as concentration of mercury in WH increases. PW is preferable to use in practice for tailings remediation from mercury contamination since it does not require cultivation in a greenhouse and shows BCF values comparable with WH.

Phosphorus Partitioning in a Storm Water Pond

Abstract Storm water ponds are commonly employed to trap sediments, nutrients and other pollutants in non-point runoff. Aquatic macrophytes are thought to offer enhanced nutrient control via nutrient uptake and other processes. This study sampled and compared the phosphorus contents of water, sediment, and a dominant macrophyte, Stuckenia pectinata (Sago Pond Weed), in a storm water detention pond in the fall of 2013 and 2014. Phosphorus concentrations [ug P (g material)−1] were much higher in macrophyte tissues than in sediment and water, but the areal amounts of phosphorus (mg P m−2) bound in these three forms were ranked differently: sediment>>water>macrophyte, with macrophyte-bound P accounting for only <1–2% of total P in this pond. Macrophyte management may, therefore, have only marginal effectiveness in nutrient control by storm water detention ponds, although macrophytes support a variety of other ecosystem services.

Invasive species may offer advanced phytoremediation of endocrine<br>disrupting chemicals in aquatic ecosystems

Abstract One of the major areas of advancement in environmental science is bioremediation. Researchers have been using bacteria, fungi, algae and now macrophytes to remove pollutants from aquatic and terrestrial ecosystems. Here we share the results of a study on the macrophyte uptake of xenoestrogens from an urban river. We found that the invasive curly leaf pond weed ( Potamogeton illinoensis ) accumulated an average of 66% higher levels of estrogenic compounds and 94% more Bisphenol-A than the native Illinois pondweed ( Potamogeton crispus ) in an urban river, in the watershed for the greater Chicago, IL area. The invasive species accumulated 76%more estrone, 55% more 17 β-estradiol and 31% more 17 α-ethynylestradiol than the native species. The Non-native plants were also 72% larger than the native Illinois Pondweed. Managers may consider using invasive species to remove pollutants from ecosystems and restore ecosystem biogeochemistry. Key words : Endocrine Disrupting Chemicals, Environmental Remediation, Invasive Species

Wetlands and Ponds for Stormwater Treatment in Subtropical Australia: Their Effectiveness in Enhancing Biodiversity and Improving Water Quality?

Abstract:Stormwater best management practice is aimed at reducing potential downstream impacts on aquatic ecosystem health. Sediment basins, wetlands and ponds are commonly used in subtropical Australia for water‐quality improvement; they also have the potential to enhance aquatic biodiversity in urbanised catchments. Two retrofit field sites in Brisbane, Australia were monitored for water quality and ecosystem health. The Golden Pond “wetland system” treatment train consisted of a sediment basin and two wetlands. The Bridgewater Creek “pond system”, consisted of a sediment basin and five ponds. Suspended solids were reduced during wet weather, but increased during dry weather due to resuspension by ducks. NO3‐N decreased in both wet and dry weather. NH4‐N increased probably due to ammonification of organic matter. PO4‐P decreased. The removal of soluble NO3 and PO4 is indicative of biological uptake by phytoplankton submerged pond weeds and periphyton attached to aquatic macrophytes. Macroinvertebrate species richness increased, and mosquitoes were not a problem due to predation of larvae by macroinvertebrates. Macrophyte survival was adversely affected by flash flooding and increased inundation. Although water quality objectives were not consistently achieved, both systems were effective in reducing suspended solids and nutrients from stormwater runoff and provided a habitat for aquatic organisms.

Is the decline of birds and amphibians in a steppe lake of northern Patagonia a consequence of limnological changes following fish introduction?

1. Laguna Blanca, in Laguna Blanca National Park, is a lake in Patagonia which has been designated as a Ramsar site since 1971 because of bird diversity and abundance and importance for nesting, particularly for the black neck swan, Cygnus melanocoryphus. It is also valued for its populations of endemic amphibians, Atelognathus patagonicus and Atelognathus praebasalticus. 2. Avian and amphibian populations have decreased dramatically in recent years. Percichthys colhuapiensis, Percichthys trucha (Pisces, Percichthyidae), Salmo trutta and Oncorhynchus mykiss (Pisces, Salmonidae) were introduced into Laguna Blanca in 1965. Since 1986, no Atelognathus frogs have been found. The abundance of swans and coots, which are strongly associated with macrophytes for nesting and feeding, has diminished drastically, whereas piscivorous birds have increased. 3. The fishless condition of some neighbouring small lakes with abundant pond weeds, aquatic birds and endemic amphibians, was assessed in order to compare the physical and chemical characteristics and the quantitative composition of the benthos among lakes. Fish presence at Laguna Blanca and its absence at El Burro, Antiñir and Jabón lakes, were confirmed. Compared with previous results, it seems that the abundance of Amphipoda (Hyalella), Copepoda and Cladocera at Laguna Blanca has decreased, while Acari has increased and Notostraca has disappeared. Water transparency has diminished in Laguna Blanca and now is lower than that of fishless lakes. 4. P. colhuapiensis were captured only in Laguna Blanca, with the highest captures in the littoral zone. The population shows rapid individual growth in the early years and an absence of fish older than 6 years. The preponderance of benthos and the presence of macrophytes in the gut contents of adult P. colhuapiensis appear to indicate that they are important consumers of these resources. 5. This paper concludes that fish introduction in Laguna Blanca led to a complex trophic cascade effect (fish predation on tadpoles, fish competition for avian food, bottom disturbance, zooplankton reduction) producing deleterious effects on the amphibian and bird populations. Copyright © 2006 John Wiley & Sons, Ltd.

Electrochemical methods for assessing the effect of metal ions on the functional characteristics of the phytocenosis of surface water

It was proposed to estimate the toxicity of physiologically active metal species from a change in the functional characteristics of the phytocenosis of surface water (daily variations in pH and the concentration of dissolved O2in water of model mesocosms with a given phytocenosis biomass). The effect of Zn(II), Cd(II), Cu(II), Ni(II), and Co(II) on the functional characteristics of phytoplankton and pond weed was evaluated by a toxicity coefficient, which showed a change in pH or in the concentration of dissolved O2after a 1-h action of 1 mg (1 mmol) of a metal on the functioning of the unit of a phytocenosis biomass in unit volume of test natural water.

The effects of oestrogenic substances on two components of freshwater ecosystems

The effects of an oestrogenic compound, similar to those recently linked with falling human sperm counts, were investigated in two common freshwater organisms commonly used in education Oestrogenic compounds have recently been linked with falling sperm counts in human males and also with cancer of the testes and breast. If these compounds can have such dangerous and dramatic effects in humans, as well as affecting sexual behaviour and physiology of fish, what effects do they have on other members of freshwater food chains? The aim of this investigation was to perform some simple experiments using basic laboratory facilities for student research projects. Daphnia, an important primary consumer and food source for fish, was exposed to increasing amounts of ethynyloestradiol, an oestrogen commonly used in contraceptive tablets. The higher concentrations of the oestrogen (0.1 to 1.0 ppm) were found to significantly reduce the heart rate of the Daphnia after approximately 30 minutes' exposure. It is proposed that such a reduction in the activity of oestrogen exposed Daphnia would make them more prone to predation and therefore increase the accumulation of oestrogens by fish. A further experiment investigated the effects of the oestrogen on photosynthesis in Elodea, a common pond weed. The same concentrations of ethynyloestradiol increased photosynthetic rates which could lead to a proliferation in growth. This again would promote the transfer of these compounds if they accumulate in the tissues for aquatic plants. These experiments on a currently significant topic were performed using readily available organisms and a small capital expenditure, thus making them a pertinent and interesting practical for both Alevel and undergraduate students.

Simplex optimisation of conditions for the determination of antimony in environmental samples by using electrothermal atomic absorption spectrometry

Analysis of the total antimony in plant material was unsuccessful using the electrothermal atomic absorption spectrometry (ETAAS) conditions recommended by the instrument manufacturer. For this reason, an optimisation procedure utilising the Plackett-Burman method, simplex optimisation and visualisation of the generated response surface via principal components analysis, was carried out. The Plackett-Burman method was used to eliminate four of the initial variables chosen. Four variables (atomisation temperature, atomisation time, ash temperature and modifier concentration) were subsequently optimised using the composite modified simplex method and the results were visualised as a contour diagram, after reduction to two principal components. The optimised conditions were used for the analysis of both an acid digested pine needle standard reference material (NIST 1575) and a pond weed sample, collected from a contaminated site at Yellowknife Bay, Yellowknife, NWT, Canada. The total concentration of antimony present in the pine needles was statistically indistinguishable from the non-certified value, as was the value for the pond weed sample, compared with a value determined by neutron activation analysis (NAA). The results for the analysis of the pond weed sample by ETAAS agreed with those obtained from a subsequent analysis by inductively coupled plasma-mass spectrometry.

Simplex optimisation of conditions for the determination of antimony in environmental samples by using electrothermal atomic absorption spectrometry

Analysis of the total antimony in plant material was unsuccessful using the electrothermal atomic absorption spectrometry (ETAAS) conditions recommended by the instrument manufacturer. For this reason, an optimisation procedure utilising the Plackett-Burman method, simplex optimisation and visualisation of the generated response surface via principal components analysis, was carried out. The Plackett-Burman method was used to eliminate four of the initial variables chosen. Four variables (atomisation temperature, atomisation time, ash temperature and modifier concentration) were subsequently optimised using the composite modified simplex method and the results were visualised as a contour diagram, after reduction to two principal components. The optimised conditions were used for the analysis of both an acid digested pine needle standard reference material (NIST 1575) and a pond weed sample, collected from a contaminated site at Yellowknife Bay, Yellowknife, NWT, Canada. The total concentration of antimony present in the pine needles was statistically indistinguishable from the non-certified value, as was the value for the pond weed sample, compared with a value determined by neutron activation analysis (NAA). The results for the analysis of the pond weed sample by ETAAS agreed with those obtained from a subsequent analysis by inductively coupled plasma-mass spectrometry.

Effects of paraquat and lead on fishOreochromis hornorum

Herbicides are used for controlling weeds in ponds, reservoirs, and irrigation canals. Paraquat (PQ) causes toxic effects on fish Roach fry and Perch fry, and produce morphologic alterations on salmon. In aquatic contamination, lead (pb) also produced ecologic unbalance. It is accumulated in gills and liver of fish and diminished reduced-glutathion in eritrocites. This work reports results of studies of exposure to PQ and Pb in fish.

Toxicity of fluridone to aquatic invertebrates and fish

AbstractThe acute and chronic toxicities of the herbicide fluridone to aquatic invertebrates and fish were evaluated. The acute median lethal concentrations (LC50s) of fluridone were 4.3 ± 3.7 mg/L (x̄±SD) for invertebrates (n = 15) and 10.4±3.9 mg/L for fish (n = 28). In chronic studies, no effects were detected when daphnids (Daphnia magna) were continuously exposed to fluridone concentrations of 0.2 mg/L or less for 32 d, amphipods (Gammarus pseudolimnaeus) to 0.6 mg/L or less for 60 d or midge larvae (Chironomus plumosus) to 0.6 mg/L or less for 30 d. Fathead minnows (Pimephales promelas) were not affected by continuous exposure to fluridone concentrations of 0.48 mg/L or less over their life cycle. The growth and survival of channel catfish (Ictalurus punctatus) were not adversely affected by continuous exposure to fluridone concentrations of 0.5 mg/L or less for 60 d after hatching. The channel catfish accumulated fluridone concentrations two to nine times greater than that in the water. The recommended application rate of 1 lb/acre of fluridone to a pond with an average depth of 3 ft provides a theoretical concentration of 0.1 mg/L. Thus, an initial fluridone concentration of 0.1 mg/L or less is recommended to control weeds in ponds. Consequently, fluridone is not expected to have adverse effects on the species tested or on similar nontarget aquatic organisms.

水田多年生雑草の繁殖特性の解明と防除に関する研究

The present studies have been undertaken to obtain basic information on the ecological characteristics of propagules and factors affecting their formation and death. Such information is necessary for the control of perennial weeds whose incidence has increased in various areas in recent years. The experiments were conducted at the Central Agricultural Experimental Station in Konosu, Saitama, during the period 1971-1980.1. Based on the ecological characteristics of propagules of perennial weeds in paddy fields the weeds were classified into three types as follows; non-clonal growth type, rhizome type and prostrated type according to the growth pattern of the above-and underground organs.Weeds belonging to the non-clonal growth type were found to produce many seeds and propagation through seeds was easy. Scirpus juncoides, Alisma canaliculatum and Sagittaria trifolia (arrow head) belong to this type. Among them, the former two species propagate through seeds in paddy fields. Rhizome type weeds propagate with propagules such as tubers and rhizomes. Cyperus serotinus (cyperus), Eleocharis kuroguwai (water chestnut) and Sagittaria pygmaea (pygmaea arrowhead) belong to this type. Weeds of this type propagate actively and cause serious damage to rice plants. In the prostrated type weeds, runner or rhizomes grow rapidly underground at a comparatively shallow depth and regenerate easily even when runners or rhizomes are cut in short pieces. Paspalum distichum and Oenanthe javanica belong to this type.2. Length of dormancy period of propagules, uniformity of awakening from dormancy and requirement of oxygen for germination are internal factors that affect the generation of weeds. In addition the morphology and function of propagules were found to be closely related with the emergence and propagation of weeds.3. As for the propagule formation, pygmaea arrowhead is a plant insensitive to photo period which produces tubers 50 to 60 days after emergence even if the date of emergence varies.As for the propagule formation of cyperus, water chestnut, arrowhead and Potamogeton distinctus (pond weed), these are short-day plants which produce propagules in the fall although the sensitivity to short-day varies among the species. Heading and flowering are controlled by short-day in cyperus and water chestnut as well as tuber formation, while in the other three species the response to tuber formation is not controlled by short-day.4. The formation of propagules varies depending on the temperature and soil moisture as well as on daylength. The propagule formation in all of the above mentioned five species, was inhibited by high temperature. Especially in the case of the pond weed, a temperature higher than 30°C inhibited winter bud formation almost completely.When the density of rice plants is high, the emergence of perennial weeds with broad leaves such as arrow head and pond weed is markedly suppressed due to shading. As a result no propagule formation was observed after a period of three years.5. Location of propagules in soil is different in each weed. It is shallowest for pygmaea arrowhead and cyperus in which most of the propagules are produced at depths ranging between 5 and 10cm. On the other hand, pond weed produces propagules in a deeper zone immediately above the subsoil. Water chestnut and arrow head show a characteristic vertical distribution of propagules.6. Propagules of pygmaea arrowhead, cyperus and water chestnut died when their moisture content decreased to 40%, whereas those of the pond weed were much more resistant to desiccation. On the other hand, the lowest temperature lethal to propagules ranged between -5°C and -7°C, being lowest in cyperus and highest in pygmaea arrowhead.7. As for weed control, use of herbicides and control through cultural practices were investigated.

Obligate Anaerobic Bacteria in the Gastrointestinal Microflora of the Grass Carp (Ctenopharyngodon idella), Goldfish (Carassius auratus), and Rainbow Trout (Salmo gairdneri)

Grass carp (Ctenopharyngodon idella), bred in Arkansas and maintained in British Columbia under defined culture conditions on pelleted diets and on aquatic weeds, were examined to determine their commensal gastrointestinal bacterial flora. Using anaerobic incubation, the total bacterial numbers cultured ranged from 6 × 104 to 4 × 108 (average 4 × 106) per g of alimentary tract plus contents. Obligately anaerobic bacteria were isolated and identified as species of Actinomyces, Bacteroides, Eubacterium, Fusobacterium, and Peptostreptococcus. This is the first description of the presence of these strictly anaerobic organisms in the gastrointestinal tract of fish. Indeed, many of the anaerobes isolated did not conform to previously described species. Members of the Genus Clostridium were also isolated by enrichment culture and appeared to be associated with a pond weed diet. A wide variety of facultative anaerobic bacteria were also isolated, with Aeromonas hydrophila predominating. The gastrointestinal tracts of goldfish (Carassius auratus) were also found to contain sizable numbers of obligate anaerobes, but the gastrointestinal tracts of hatchery-cultured rainbow trout (Salmo gairdneri) contained insignificant numbers. Key words: grass carp, anaerobic bacteria, gastrointestinal microflora, Aeromonas hydrophila, rainbow trout, goldfish

Cellulolytic bacteria as primary colonizers ofPotamogeton pectinatus L. (Sago Pond Weed) from a Brackish South-Temperate Coastal Lake

Bacteria adhering to newly emerged and decomposing leaves ofPotamogeton pectinatus L. were examined using scanning electron microscopy. Bacteria obtained from mature leaves were isolated, grown in pure culture, and allowed to infect bacteria-free leaves. Infected leaves and individual isolates were examined by scanning electron microscopy. The method provided detail of the forms of bacterial attachment to leaf surfaces.Supernatants from isolate cultures were assayed for cellulase activity. Six out of eight isolates produced extracellular cellulase in medium containing carboxymethyl cellulose. In one isolate cellulase was produced at discrete intervals, at the beginning and end of the growth cycle. The adhesion of the isolates toP. pectinatus leaves, as well as their possession of cellulase, are considered as evidence of an active role of bacteria in the degradation ofP. pectinatus foliage. The system is unusual in that bacteria, as opposed to fungi, are primary colonizers of the leaves.

Biomass and distribution of underground parts of Potamogeton perfoliatus L. and P. Lucens L. in Mikołajskie Lake, Poland

The rhizomes of Potamogeton lucens penetrate the lake bottom to a maximum depth of 20 cm (on average to a depth of 9 cm), thus exceeding the average depth of penetration by rhizomes of Potamogeton perfoliatus by a factor of 1.5–4.5. The contribution of the biomass of underground parts to the biomass of the whole plant is on average 49% for P. lucens and 39% for P. perfoliatus, independent of the structure of the lake bottom. There is a positive correlation between the biomass of underground and above-ground parts. Field experiments show a similar rate of increments and losses in rhizome biomass of both species of pond weed.

Control of Weeds Harmful to Water Uses in the West

An extensive program of controlling aquatic and ditchbank weeds in irrigation and drainage canals in seventeen western states prevented weed losses of $15,860,026 in one typical year, an annual saving of $7,746,729 over control costs. The improved methods used were developed in a research program conducted since 1947 by the United States Agricultural Research Service in cooperation with the Bureau of Reclamation and several state agricultural experiment stations. Expansion of the cooperative research program in 1961 resulted in the development of several effective and other promising chemical methods of controlling submersed weeds in ponds, lakes, and reservoirs; also of the most troublesome water-wasting phreatophytes growing on river flood plains, along small streams, and around reservoirs. However, moost of these methods are expensive and are not used extensively in the West. Investigations are being continued to discover more effective, less expensive, and safer chemical, mechanical, biological, and ecological methods of controlling weeds harmful to water uses in the West.

Herbivorous Fish to Control Pithophora sp. and Other Aquatic Weeds in Ponds

Herbivorous Fish to Control Pithophora sp. and Other Aquatic Weeds in Ponds