Use Of Aquatic Plants Research Articles

Design and Application of Plant Ecological Space Technology in Water Eutrophication Control

AbstractThe use of aquatic plants has recently become a popular technique for ecological restoration and purification of eutrophic rivers and lakes. In this paper, various technologies were studied...

Potential use of aquatic plants in constructed wetlands for simultaneous removal of Phosphate and COD from laundry wastewater

One component of household wastewater that has a bad impact on the environment is waste that comes from washing which uses detergent, due to a fairly high phosphate and chemical oxygen demand (COD) concentration. The purpose of this study was to determine the potential of using aquatic plants to reduce phosphate and COD levels from laundry waste. This research was carried out using constructed wetlands model of laboratory scale using the combination of flow types of subsurface flow systems (SFS) and the type of vertical flow system (VFS) with a waste residence time of 5 days and 10 days. Based on the results, for model I, the average percentage of COD levels reduction is 67.62% and phosphate is 13.89%, while in model II, the average percentage of COD reduction is 59.93% and phosphate is 14.36%, after 10 days of waste residence time. Aquatic plants used in the modeling of constructed wetland can grow and reproduce well, this can be indicated by the growth of new shoots and flowers of these plants.

Optimal conditions for the biological removal of ammonia from wastewater of a petrochemical plant using the response surface methodology

High concentrations of nitrogen compounds, such as ammonia observed in the petrochemical industry, are the major environmental pollutants. Therefore, effective and inexpensive methods are needed for its treatment. Biological treatment of various pollutants is a low cost and biocompatible replacement for current physico-chemical systems. The use of aquatic plants is an effective way to absorb the nutrient pollutants. In this study, the optimal operating conditions in the biological removal of ammonia from the urea-ammonia wastewater of Kermanshah Petrochemical Company by Lemna gibba were determined using the response surface methodology. Lemna gibba was collected from the ponds around Kermanshah and maintained in a nutrient medium. Effect of the main operational variables such as ammonia concentration, residence time and Lemna gibba to surface ratio on optimal conditions of ammonia removal from wastewater has been analyzed using the Box-Behnken model design of experiments. Model numerical optimization was performed to achieve the maximum amount of ammonia removal from wastewater. The ammonia removal percentage varied from 13% to 88%, but the maximum amount of ammonia removal was determined at ammonia concentration of 5 ppm and Lemna gibba residence time of 11 days in wastewater based on the quadratic model. Lemna gibba to surface ratio of 2:5 was measured at 96.449%. After optimization, validation of ammonia removal was performed under optimum conditions and measured at 92.07%. Based on the experimental design and the predicted under model conditions, the maximum amounts of ammonia removal percentage in the experiments were 82.84% and 88.33% respectively, indicating the high accuracy of the model to determine the optimum conditions for the ammonia removal from wastewater.

Increased lead and cadmium tolerance of Typha angustifolia from Huaihe River is associated with enhanced phytochelatin synthesis and improved antioxidative capacity

ABSTRACTHeavy metal contamination of water is an increasing environmental problem worldwide, and the use of aquatic plants for phytoremediation of heavy metal pollution has become an important subject of research. One key to successful phytoremediation is the identification of plants that are efficient at sequestering heavy metals. In this study, we examined the growth and heavy metal accumulation of Typha angustifolia and compared growth characteristics and tolerance mechanisms in plants from the Huaihe and Chaohu Rivers irrigated with different concentrations of lead (Pb) and cadmium (Cd). T. angustifolia from Huaihe River showed enhanced tolerance and accumulation of Pb and Cd and had greater biomass and more vigorous growth than the ecotype from Chaohu River. In addition, higher phytochelatin (PC) content and significantly higher superoxide dismutase and catalase activities were detected in T. angustifolia from Huaihe River than in T. angustifolia from Chaohu River. These findings suggest that high Pb and Cd accumulation and tolerance in T. angustifolia from Chaohu River is associated with its higher PC synthesis and better antioxidative capacity, and that the Huaihe ecotype of T. angustifolia might also be an efficient species for phytoremediation of Pb and Cd in water contaminated by heavy metals.

In-situ Biological Water Treatment Technologies for Environmental Remediation: A Review

Water treatment technologies can be classified as in-situ or ex-situ technologies. In-situ biological techniques include the use of aquatic plants, aquatic animals, and microbial remediation. Approaches to alleviate surface water pollution should use bioremediation methods as a primary technique. These methods should be tested not only on rivers and lakes, but also on other polluted surface streams. Furthermore, bioremediation processes need to be optimized depending on flow condition and nutrient availability. This paper comprehensively reviews the latest surface water remediation techniques that are suitable for in-situ applications, focusing on bioremediation technologies as effective techniques to remedy polluted water.

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

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.

Lemna minor L.: As bioindicator of heavy metal pollution in Skadar lake: Montenegro

The use of aquatic plants to analyze the heavy metal pollution of a lake environment has a number of advantages over the standard chemical methods of the analysis of metal presence in water and sediment. The macrophyta Lemna minor L., sampled from Lake Skadar in Montenegro has been used as a bio-indicator. Floating macrophyte L. minor accumulates metals from water through its submerged roots and floated leaves. The contents of Cd, Cu, Co, Cr, Mn, Ni, Pb, Zn, Sr and V were determined in sediments, water and the plant. The results obtained indicated a very high capacity of L. minor for the accumulation of Mn. In addition, higher Zn concentration was found in root tissue comparing to the sediment. The concentration of the other metals under investigation decreases in the following order: sediment > L. minor(root) > L. minor(leaf) > water. Higher concentrations of all metals in the tissue of L. minor were observed at the end of the growing season. A higher metal content was recorded in the root compared to the leaf. In descending order, the concentrations in plant tissues were found for the following metals: Mn > Zn > Sr > Cu > Ni > Pb > Co > V > Cr > Cd, while the series of bioaccumulation is, in descending order: Mn > Zn > Ni > Co > Pb > Cu > Cr > V > Sr > Cd.

Arsenic Uptake by Lemna minor in Hydroponic System

Arsenic is hazardous and causes several ill effects on human beings. Phytoremediation is the use of aquatic plants for the removal of toxic pollutants from external media. In the present research work, the removal efficiency as well as the arsenic uptake capacity of duckweed Lemna minor has been studied. Arsenic concentration in water samples and plant biomass were determined by AAS. The relative growth factor of Lemna minor was determined. The duckweed had potential to remove as well as uptake arsenic from the aqueous medium. Maximum removal of more than 70% arsenic was achieved at initial concentration of 0.5 mg/l arsenic on 15th day of experimental period of 22 days. Removal percentage was found to decrease with the increase in initial concentration. From BCF value, Lemna minor was found to be a hyperaccumulator of arsenic at initial concentration of 0.5 mg/L, such that accumulation decreased with increase in initial arsenic concentration.

Phytoaccumulation of zinc using the duckweed Lemna gibba L.: effect of temperature, pH and metal source

The use of aquatic plants in the removal of pollutants is an alternative technique for the remediation of contaminated waters. In this work, the capacity of accumulation of soluble Zn by the duckweed Lemna gibba L. native to a Mediterranean area (North-east Algeria) was studied under controlled conditions. The effect of temperature (17, 21, 25 and 29°C), medium pH (3, 4, 5 and 6) and Zn source (ZnSO4, Zn(NO3)2 and ZnCl2) was investigated in order to assess the ability of the plants to remove metal pollutant under various conditions. The results revealed that, at 21, 25 and 29°C, the plants reduced initial Zn concentration (∼18 mg L-1) to 4.64, 1.69 and 1.92 mg L-1, respectively, with 9.1–22.1 mg g-1 DW of Zn accumulated in the biomass. Low Zn accumulation in L. gibba biomass (7.5 mg g-1 DW) corresponding to a low plant growth was observed at pH 3 and 4 indicating that this species is not tolerant to water acidity. A very low Zn concentration in Lemna biomass (1.04 mg g-1 DW) was observed when Zn(NO3)2 was used as Zn source. The results obtained in this study demonstrated that temperature ⩾ 21°C and pH values of 5 and 6 are favourable factors for the phytoaccumulation of Zn by L. gibba L.

Uptake of uranium by native aquatic plants: potential for bioindication and phytoremediation

The work presented here is a part the on going study on the uraniferous geochemical province of Central Portugal in which, the use of aquatic plants as indicators of uranium contamination is being probed using aquatic plants emphasizing their potential use in the emerging phytotechnologies. Even though we have observed very low concentration of U in the fresh waters of the studied sites we found a set of vegetable species with the ability to accumulate U in concentrations which are orders of magnitude higher than the surrounding environment. We have observed that Apium nodiflorum, Callitriche stagnalis, Lemna minor and Fontinalis antipyretica accumulated significant amounts of uranium, whereas Oenanthe crocata excluded U. These results indicate substantial scope for proper radiophytoremediation and phytosociological investigation exploiting the native flora. These species show great potential for phytoremediation because they are endemic and easy to grow in their native conditions. A. nodiflorum and C. stagnalis have high bioproductivity and yield good biomass.

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

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.

Use of aquatic plants to create fluctuating hypoxia in an experimental environment

In freshwater systems, dissolved oxygen (DO) saturation frequently fluctuates, falling at night and rising during the day in response to respiration and photosynthesis, respectively, of aquatic biota. Low DO (hypoxia) is a common cause of fish kills in freshwater systems around the world. Laboratory studies on responses of fish to fluctuating DO are currently limited, and require techniques that produce a realistic cycle of DO depletion and replacement. Artificial DO-depletion mechanisms frequently used for hypoxia studies may underestimate the field effects of hypoxia on fish because of the lack of the naturally occurring synergistic effect of lower pH, and seldom allow fish to employ behavioural adaptations to hypoxia, such as aquatic surface respiration. We demonstrate proof-of-principle for an alternative method of creating fluctuating hypoxia in an experimental environment, using the natural rhythms of photosynthesis and respiration of aquatic plants to create realistic conditions. A range of volumes of aquatic macrophytes were used alone and in combination with fish to lower DO saturation in sealed freshwater aquaria, and achieved DO saturations as low as 1.3%. This cost-effective method can be deployed over long periods with minimal effort in comparison to traditional methods of DO reduction.

PHYTOREMEDIATION OF LEAD FROM WASTEWATER USING AQUATIC PLANTS

Increasing urbanization, industrialization and over population is one of the leading causes of environmental degradation and pollution. Heavy metals such as Pb, Zn, Cd, As etc. are the most toxic pollutants which show hazardous effects on all living things. Lead is one such pollutant which disrupts the food chain and is lethal even at low concentrations. The prevailing purification technologies used for removal of contaminants are not only very costly but causes negative impact on ecosystem subsequently. Phytoremediation, an eco-friendly technology which is both ecologically sound and economically viable is an attractive alternative to the current cleanup methods that are very expensive. This technology involves efficient use of aquatic plants to remove, detoxify or immobilize heavy metals . The purpose of this review is to assess the current state of phytoremediation as an innovative technology and to discuss its usefulness and potential in the remediation of lead contaminated water.

BIOSORPTIVE REMOVAL OF HEAVY METALS FROM WASTEWATER USING DUCKWEED

Water pollution has been recognized as a problem for decades. The use of heavy metals in industries and their regular mining increases their concentration in water bodies. Unlike organic compounds, metals cannot degrade, and therefore effective cleanup requires their immobilization to reduce or remove toxicity. A few conventional methods employed to remove heavy metals from wastewater are expensive, require skilled labors and maintenance. Therefore, the use of aquatic plants has come up since the last few decades. Duckweed is one such plant employed as a biosorbent and has been considered a better alternative than any other aquatic plant because of high tolerance to cold than water hyacinth, more easily harvested than algae, capable of rapid growth (0.1 to 0.5 g g-1 day-1) and small size of plant. This study aims to determine the suitability of this plant for biosorbing toxic heavy metals commonly found in industrial wastewater, domestic wastewater, and seepage water.

An eco-sustainable green approach for heavy metals management: two case studies of developing industrial region

Multifaceted issues or paradigm of sustainable development should be appropriately addressed in the discipline of environmental management. Pollution of the biosphere with toxic metals has accelerated dramatically since the beginning of the Industrial Revolution. In present review, comparative assessment of traditional chemical technologies and phytoremediation has been reviewed particularly in the context of cost-effectiveness. The potential of phytoremediation and green chemicals in heavy metals management has been described critically. Further, the review explores our work on phytoremediation as green technology during the last 6years and hand in hand addresses the various ecological issues, benefits and constraints pertaining to heavy metal pollution of aquatic ecosystems and its phytoremediation as first case study. Second case study demonstrates the possible health implications associated with use of metal contaminated wastewater for irrigation in peri-urban areas of developing world. Our researches revealed wetland plants/macrophytes as ideal bio-system for heavy metals removal in terms of both ecology and economy, when compared with chemical treatments. However, there are several constraints or limitations in the use of aquatic plants for phytoremediation in microcosm as well as mesocosm conditions. On the basis of our past researches, an eco-sustainable model has been proposed in order to resolve the certain constraints imposed in two case studies. In relation to future prospect, phytoremediation technology for enhanced heavy metal accumulation is still in embryonic stage and needs more attention in gene manipulation area. Moreover, harvesting and recycling tools needs more extensive research. A multidisciplinary research effort that integrates the work of natural sciences, environmental engineers and policy makers is essential for greater success of green technologies as a potent tool of heavy metals management.

Use of aquatic plants in removing heavy metals from wastewater

Phytotechnologies involving use of plants for pollutant removal gained importance during the last two decades. Terrestrial and aquatic plants possess high metal sorption capacity, and hence find their use as inexpensive materials for removing metals from environment. Aquatic biomass irrespective living or dead, exhibits capacity to remove heavy metals from wastewater. The sequestration of heavy metals in plants is achieved mainly by absorption and accumulation mechanisms. Features such as high growth rate with high metal accumulation/retention capacity widen scope of aquatic plants for use as non-conventional sorbents and further strengthen their role in framing low cost, eco-friendly wastewater treatment technologies.

Kentucky Bluegrass Response to Use of Aquatic Plants as a Soil Amendment

Rapid aquatic plant growth in Michigan's smaller lakes has reduced their navigability and recreational use. Harvested aquatic weeds have posed a new waste disposal issue for municipalities. Application of lake weeds as a soil amendment on area farms was viewed as a possible waste management option that might benefit local sod producers. The objectives of this study were to 1) estimate the amount of plant-available N (PAN) released from lake weed material, 2) determine the chemical composition of aquatic plant tissues and their effect on plant-available moisture, and 3) study turfgrass response to lake weed applications using the criteria of turfgrass quality, growth, and N uptake. Rates of lake weed refuse applied to field plots were 96, 161, and 206 Mg·ha-1. Two 47-day laboratory incubations were conducted with the same rates of refuse. Relative to biosolids, the metal content of the lake weeds was low and the nutrient content high. One megagram of lake weeds contained 0.37 kg of P and 2.5 kg of K. The decay constant for the C fraction in lake weeds was 8 to 10 days and 16 days for the N fraction. Estimates of the N supplied by lake weeds (570, 960, and 1200 kg PAN/ha) were based on data from C and N incubations. Application of lake weeds significantly increased plant-available soil moisture and significantly enhanced sod establishment and turf density, resulting in decreased weed pressure. However, excess N was present at higher application rates. Management concerns during the application of lake weeds should focus on nutrient loading and the timing of plant-available N release. Depending on methods of weed harvesting, we observed that large amounts of unwanted trash present in the plant biomass could discourage use by growers. Land application of lake weed refuse could ease waste disposal problems, reduce fertilizer inputs for sod growers, and improve the moisture status of sands. Further, this information can be of value to environmental regulatory agencies in determining safe and proper use of such waste materials.

Assessment of the use of biomarkers in aquatic plants for the evaluation of environmental quality: application to seagrasses

The use of aquatic plants as bio-indicators constitutes an irreplaceable tool for investigation in ecological research, applied to the conservation of littoral ecosystems. Today, studies in both the laboratory and the field have provided encouraging insights into the capacity of aquatic plants to act as biomonitors of environmental quality, through the use of biomarkers, and these are reviewed here. Photosynthetic activity, secondary metabolites, heat shock proteins, enzymes of detoxication, and oxidative stress biomarkers were measured in the case of various stressors, (e.g. light, thermal, hydric/haline stress, or herbicides, metals, organic contaminants). Most of them seem to be valuable and early markers of the environmental conditions, as demonstrated by experimentations carried out on Posidonia oceanica. Nevertheless, none can be in itself a valuable solution, and only a multiparametric approach, including both ‘physiological’ biomarkers, biomarkers of general stress and more specific biomarkers seems to be appreciable in an ecotoxicological diagnostic.

Use of Aquatic Plants and Algae for Decontamination of Waters Polluted with Chlorinated Alkanes

ABSTRACT The transformation of carbon tetrachloride (CT) and hexachloroethane (HCA) by aquatic plants and freshwater algae was investigated. Stressed, axenic, and physiologically healthy freshwater plants all transformed the two chlorinated alkanes, yielding similar breakdown products. Experiments conducted with dead plants were used to indirectly test the hypothesis that dead aquatic plants maintain and possibly contribute to the dehalogenase activity observed in organic-rich sediments. After exposure of the aquatic plants and algae to HCA- and CT-dosed solutions, a rapid sorption (or sequestration) step followed by a slow transformation lasting several hours thereafter was observed. The kinetics data were adequately described by two first-order rate equations; pseudo-first-order sorption rate coefficients were calculated for the initial rapid adsorption and transformation steps. The identified metabolites extracted from plants indicated that more than one pathway, possibly requiring different reactants, mediated the phytotransformation reactions. Mass balance estimations confirmed that >80% of the parent chemical was sequestered, transformed, and/or assimilated by the biomass. The metabolic activity observed with dead plants and algae suggests that photoautotrophs maintain this activity at death, and the active agents could become bound to the sediment-organic matrix as plants die, decay, and are buried in sediment. The results of this study suggest the potential usefulness of aquatic plants and freshwater algae in the removal of chlorinated alkanes from water and remediation of aquatic environments.

Experimental Research into the use of Aquatic Plants for the Improvement of Water Quality in the Main Tributary to Lake Biwa

The water quality in Lake Biwa is constantly affected same levels of concentrations in COD, T-N, T-P, but algae bloom or red tide is practically an annual occurrence. So, it is offen inadeguate for a source of water supply. Therefore it is necessary to make improvement to the water purification capacity of the main tributary into Lake Biwa, to augment past water quality preservation meseaurs.This report describes the results of field experiments in water purification using aquatic plants. The water purification mechanism using aquatic plants was analyzed, and the optimum conditions for nutrients removal were determined.The data generated by this study will he utilized for the design and operation of river water purification facilities.