The bioadhesion and effects of microplastics and natural particles on growth, cell viability, physiology, and elemental content of an aquatic macrophyte Elodea canadensis.

Microplastics in the aquatic environment can interact with aquatic plants, but the consequences of these interactions are poorly understood. Therefore, the aim of this study was to investigate the effects of microplastics commonly found in the environment, namely polyethylene (PE) fragments, polyacrylonitrile (PAN) fibres, tire wear (TW) particles under a relevant environmental concentration (5000 particles/L) on the growth, cell viability, physiology, and elemental content of the aquatic macrophyte Elodea canadensis. The effects of microplastics were compared to those of natural wood particles. The results showed that all types of microplastics adhered to plant tissues, but the effect on leaves (leaf damage area) was greatest at PE > PAN > TW, while the effect of natural particles was comparable to that of the control. None of the microplastics studied affected plant growth, lipid, carbohydrate, or protein content. Electron transport system activity was significantly higher in plants exposed to PAN fibres and PE fragments, but also when exposed to natural particles, while chlorophyll a content was negatively affected only by PE fragments and TW particles. Elemental analysis of plant tissue showed that in some cases PAN fibres and TW particles caused increased metal content. The results of this study indicated that aquatic macrophytes may respond differently to exposure to microplastics than to natural particles, likely through the combined effects of mechanical damage and chemical stress.

Estimation of background concentrations of macro- and trace elements in an aquatic plant as a basis for the passive biomonitoring of pollution.

Chemical pollution was indicated as a global environmental problem since elevated concentrations of toxic substances were recorded in almost all ecosystems worldwide. Trace elements, released to environment due to industrial, agricultural and urban activities, are of special concern due to their non-degradability, persistence, bioaccumulation in organisms and potential toxicity. Reliable methods for assessing the level of pollution are essential for proper monitoring and control of pollution. A useful tool for this purpose is the geochemical background (GB), which enables to differentiate between unpolluted and polluted areas as well as calculate pollution indices. The study presents the first attempt to estimate the background values for aquatic plants using cosmopolitan submerged aquatic macrophyte Ceratophyllum demersum as a model species. Water and plant samples were collected from 117 water bodies. Contents of 15 elements (As, Ca, Cd, Co, Cr, Cu, Fe, K, Li, Mg, Mn, Na, Ni, Pb, V, Zn) were determined using atomic absorption spectrometry and flame photometry. Four methods were tested for estimation of the background concentrations: Median ± 2Median Absolute Deviation, Iterative 2σ technique, Tukey box-plot, Grouping of data with 60 % coefficient of variation (CV). Wide ranges of element concentrations in water and various values of Contamination Factor indicated to a variety of natural and anthropogenic impacts in the studied area, which confirmed that the database covered a real environmental variability. Very different estimates of background concentrations were obtained depending on the method. The highest background values were usually given by Me±2MAD method. Grouping of data with 60 % CV was most exigent in defining a site as undisturbed, therefore this method was recommended as the most suitable for estimation of the background values for C. demersum. Pollution Load Index validated the use of estimated background concentrations as reliable for bioindication of pollution in aquatic reservoirs.

Metals in Plant Functional Types of Ombrotrophic Peatlands in the Sudetes (SW Poland).

The Sudetes are remarkable for the variety and number of peat bogs which receive nutrients via precipitation from atmospheric deposition as the only source of minerals. As this type of peat bogs with a very low buffering capacity is affected in the Sudetes by long-range exhausts from the former Black Triangle, strong response to atmospheric contamination may be expected. Therefore these peat bogs are highly suitable for bioindication purposes. As a result, metal levels in peat and plants should be controlled to evaluate potential ecological damage and to devise treatment strategies. The aim of this study was to evaluate the concentration of Cd, Cr, Cu, Fe, Hg, Mn, Ni, Pb, and Zn in species from different plant functional types (PFTs): shrubs, evergreen dwarf shrubs, deciduous dwarf shrubs, tussock sedges, non-tussock sedges, forbs, Sphagnum mosses, brown mosses, liverworts, and algae collected from peat bogs of the Izera, Karkonosze, and Bystrzyckie Mountains. PFTs of the Karkonosze peat bogs situated above the upper forest line contained higher metal concentrations than those of the Izera and Bystrzyckie peat bogs from lower altitudes and surrounded by forests. Of all PFTs, the algae Zygogonium ericetorum accumulated the highest levels of Fe, Pb, and Zn. The PFTs of Sphagnum mosses were also very effective bioindicators of Cd, Cr, Fe, Hg, and Pb deposition to peat bog ecosystems. Pb, Fe, and Cr found in the examined vascular PFTs originated from atmospheric deposition. The results showed that airborne contaminants, including the ones connected with long-range transport, can make a significant contribution to a load of trace metals in peat bogs located above the upper forest line. These airborne depositions facilitate better recognition of the transport of contaminants carried over great distances and should be taken into account in monitoring and environmental protection programs. In particular, the results, first of all, show the differences in the bioaccumulation of metals in PFTs and their response to trace metal levels in such habitats. Of all PFTs, algae and Sphagnum mosses were the best choices for bioindication of trace metal pollution in ombrotrophic mountain mires. PFTs have not been used so far for investigating ombrotrophic mountain mires in Europe. Thus results of this investigation could be extended to this type of peat bogs in the mountains of Central Europe for better selection of PFTs for bioindication purposes.

Comparative analysis of trace and macro-element bioaccumulation in four free-floating macrophytes in area contaminated by copper smelter.

NOVELTY STATEMENT: This is the first study that comprehensively compares Salvinia natans, Lemna minor, Lemna trisulca, and Azolla filiculoides growing in the field; industrially affected conditions in respect of elements contents, water-plant transfer, and bioaccumulation using statistical analyses and indexes and their suitability for phytoremediation was considered. Secondary aim of the study was to fill the gap in research on the impact of copper smelters on aquatic ecosystems. Although the manuscript describes a case study performed near copper smelter in Poland, due to the novel results and cosmopolitan distribution of the species and significant world-wide impact of industry on the environment the results may be interested to broad publicity and find substantial application.

Validation of Hydrocharis morsus-ranae as a possible bioindicator of trace element pollution in freshwaters using Ceratophyllum demersum as a reference species.

The assessment of trace metal pollution in aquatic environments remains a challenge. Chemical methods are insufficient and bioindicators seem to be the most promising alternative. Finding an adequate species is important to ensure accurate data. The combined use of several bioindicators may help to overcome the limitations of species' spatial distribution and specific reactions. The aims of the present study were to compare the contents and bioaccumulation capability of 11 trace elements in Ceratophyllum demersum and different organs of Hydrocharis morsus-ranae and to validate H. morsus-ranae as a bioindicator of pollution in aquatic reservoirs using C. demersum, an established bioindicator, as a reference species. The application of several statistical techniques allowed us to identify similarities in accumulation patterns and concentration gradients between the two species. The results showed that concentrations of Cd, Co, Cr, Cu, Mn, Ni, Pb, Rb, Zn, V in C. demersum and roots of H. morsus-ranae were similar and mostly higher than in the leaves and stems of H. morsus-ranae. The contents of Cd, Co, Cr, Li, Mn, Ni, Rb, V, Zn were positively correlated. The inner transport of metals in H. morsus-ranae was limited (TF < 1). Both species are accumulators (BF > 103) of Ni and Zn, and H. morsus-ranae also of Cu and Pb. Frog-bit roots were chosen to be most promising in bioindication. Major axis regression analysis showed that the uptake of Cd, Cr, Co, Li and Pb was similar in the two species. Neural networks demonstrated substantial uniformity in responses of C. demersum and roots of H. morsus-ranae to the type of anthropogenic activity and land use and similar spatial distributions of Cd, Cr, Co, Li and Pb. When Nemerow Pollution Index was applied, both species showed congruent gradients of contamination. Thus, H. morsus-ranae was validated as a reliable bioindicator of trace metal pollution in freshwater.

Trace element accumulation in Salvinia natans from areas of various land use types.

Salvinia natans meets many criteria for accumulative bioindicators and phytoremediation agents. However, the majority of studies on its bioaccumulation capacity were performed under controlled culture conditions. In the present study, Salvinia natans was investigated in a field study. Plant and water samples were collected from aquatic reservoirs located in areas with various dominant land uses (forested, agricultural, residential and industrial). Contents of 10 trace elements (As, Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, Zn) and phytomass were measured to estimate the bioindication and phytoremediation potential of the species. Results showed that contents of trace elements in S. natans were high compared with other aquatic ferns (Azolla japonica, A. pinata) as well as free-floating vascular plants (e.g. Pistia stratiotes, Hydrocharis morsus-ranae, Lemna sp., Eichhornia crassipes). High bioaccumulation factors for Cu, Fe, Mn, Ni, Pb and Zn confirm accumulative abilities of the plant. Application of neural networks (SOFMs) confirmed that the species may be used in bioindication: the land use type determined the composition of substances carried into water reservoirs with runoff and trace elements accumulated in Salvinia tissues. Ferns in industrial areas had the highest content of Cd, Cu and Zn, while in residential areas plants showed the highest content of As, Co, Fe, Mn, Ni and Pb. Element contents in S. natans in forested areas were the lowest. High standing stocks of Cd, Mn and Ni indicated an important role of S. natans in the cycling of elements and potential use in their removal from aquatic ecosystems.

The influence of an electric field on growth and trace metal content in aquatic plants.

It is known that both natural and artificial electric fields (EF) affect plants physiological parameters as well as germination, growth and yield. The present article describes results of a preliminary experiment on the impact of electric field on aquatic plants biogeochemistry. The objective of the present study was the assessment of the influence exerted by the electric field on growth and trace metals content of Elodea canadensis. In a laboratory experiment plants were exposed to the field intensity of 54 kV m-1 for 7 days. The plants length was measured and the content of Fe, Mn, Ni, Pb, and Zn was determined using atomic absorption spectrometry (AAS). Results showed that the application of electric field slightly enhanced the growth of E. canadensis shoots. The content of Mn and Ni was significantly lower, and Pb and Zn significantly higher in plants exposed to the electric filed, while Fe content did not differ between control and EF treatment. This provides a rationale for further studies on biological effects of electric field in trace metal contaminated waters and application of an electrically enhanced phytoremediation.

Cobalt and nickel content in Hydrocharis morsus-ranae and their bioremoval from single- and binary solutions.

Aquatic macrophytes are known to remove trace metals from surrounding water. In the present study, an attempt was made to evaluate the phytofiltration capacity of Hydrocharis morsus-ranae and to show competition between cobalt (Co) and nickel (Ni) for the better understanding of metal bioaccumulation in the species. In a laboratory experiment, H. morsus-ranae was exposed to separate (single) and binary solutions of these metals: Ni 10.7, 18.7, 32.7, 57.1, and 100 (µg L-1); Co 5.33, 9.32, 16.3, 28.6, and 50.0 (µg L-1); and 10.7 Ni + 5.33 Co, 18.7 Ni + 9.32 Co, 32.7 Ni + 16.3 Co, 57.1 Ni + 28.6 Co, 100 Ni + 50.0 Co (µg L-1). The content of Co and Ni in the plant increased with the increasing concentration in the growth medium. Competition between the metals was seen during uptake in binary solutions. Ni interfered with the accumulation of Co, resulting in a lower Co content than in plants cultivated in Co solutions. A particularly high Co content (up to 155 mg kg-1 dry weight [d.w.]) and high efficiency of Ni uptake (Bioaccumulation Factor (BF) 2572-7239) makes the species a very good accumulator of these metals. The high content of both trace metals in plant tissues (up to 511 mg kg-1 d.w. Ni and 155 mg kg-1 d.w. Co) did not affect its growth, indicating tolerance of these toxicants. The plant showed excellent ability in removing Co (up to 98.6% in solution with 5.33 µg L-1 Co) and Ni (up to 91.4% in solution with 57.1 µg L-1 Ni and 28.6 µg L-1 Co) from nutrient solution. The results suggest that H. morsus-ranae may be useful for the phytoremediation of water bodies contaminated with Co and Ni.

Does heavy metal exposure affect the condition of Whitethroat (Sylvia communis) nestlings?

Anthropogenic pollution results in high concentrations of heavy metals in the environment. Due to their persistence and a high potential for bioaccumulation, metals are a real threat for birds breeding in industrial areas. The aim of the present study has been to explore the contents of heavy metals (arsenic As, cadmium Cd, chromium Cr, copper Cu, iron Fe, nickel Ni, lead Pb and zinc Zn) in the excreta of Whitethroat (Sylvia communis) nestlings living in polluted environment and to investigate the relationship between these contents and the nestlings' condition. Excrement samples contained all the studied elements. The contents of arsenic, cadmium, copper and zinc in the excreta of nestlings from nests located close to a slag dump were several times higher than in the soil near the dump, which suggested accumulation in food consumed by the birds. Condition parameters (body mass and haemoglobin concentration) were not related to heavy metal concentrations in the nestlings' excreta, except of Zn. It is possible that Whitethroats are able to detoxicate heavy metals to a certain extent. Detailed, multi-element analysis of the environment, food and bird tissues or excreta should be performed to explore relations between different chemicals and bird condition.

A Comparative Study on Macro- and Microelement Bioaccumulation Properties of Leaves and Bark of Quercus petraea and Pinus sylvestris.

Trees are widely used for biomonitoring and filtering air in industrial, urban, and rural areas. This research was undertaken to examine accumulation capacities of macroelements (Ca, K, Mg, Na) and trace metals (As, Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, Zn) in needles and bark of Pinus sylvestris and leaves and bark of Quercus petraea growing in the vicinity of the chlor-alkali plant PCC Rokita in Brzeg Dolny (Lower Silesia, SW Poland). Because Scots pine is well studied and considered a useful bioindicator, we have used this species as a base for comparison of the accumulation ability of sessile oak that shows some features of good bioindicator, but whose biogeochemistry was scarcely studied. Results showed that for both species leaves contained more macroelements (Ca, K, Mg), whereas the bark was richer in most trace metals (Cd, Cr, Cu, Fe, and Pb). However, trees studied differed with respect to element content. Oak bark and leaves were more effective in accumulating macro- and trace elements (bark Cd, Co, Cr, Cu, K, Mg, Mn, Na, Ni, Pb and leaves Ca, Cr, Cu, Fe, K, Mg, Na, Ni) than Scots pine tissues. Nevertheless, foliar metal accumulation index of these species was similar, suggesting that their overall ability to accumulate trace metals was similar.

Changes in growth rate and macroelement and trace element accumulation in Hydrocharis morsus-ranae L. during the growing season in relation to environmental contamination.

The temporal variations in plant chemistry connected with its life cycle may affect the cycling of elements in an ecosystem as well as determine the usefulness of the species in phytoremediation and bioindication. In this context, there is a gap in knowledge on the role of floating plants for elements cycling in aquatic reservoirs. The aim of the study was to determine if there are variations in Hydrocharis morsus-ranae (European frog-bit) bioaccumulation capacity and the growth rate of its population during the growing season and to test the impact of environmental pollution on these features. The content of macroelements (Ca, K, Mg, N, Na, P, S) and trace metals (Cd, Co, Cu, Cr, Hg, Fe, Mn, Ni, Pb, Zn) was determined in H. morsus-ranae collected monthly from June to October from habitats differing in environmental contamination. The results showed that the highest content of most trace metals (Co, Cr, Cu, Hg, Mn, Ni, Zn) and some nutrients (N, P) in plants as well as the greatest bioaccumulation efficiency occurred simultaneously in the beginning of the growing season. In the following months, a dilution effect (manifested by a decrease in content) related to the rapid growth was observed. Co, Mn, and Ni content in plant tissues reflected the level of environmental contamination throughout the growing season which makes H. morsus-ranae a potential biomonitor of pollution for these metals. Considering the great bioaccumulation ability, high sensitivity to contamination, and low biomass of European frog-bit in polluted systems, further investigation is required to assess the real phytoremediation capability of the species.

Typha latifolia (broadleaf cattail) as bioindicator of different types of pollution in aquatic ecosystems-application of self-organizing feature map (neural network).

The contents of Cd, Cu, Fe, Mn, Ni, Pb, and Zn in leaves of Typha latifolia (broadleaf cattail), water and bottom sediment from 72 study sites designated in different regions of Poland were determined using atomic absorption spectrometry. The aim of the study was to evaluate potential use of T. latifolia in biomonitoring of trace metal pollution. The self-organizing feature map (SOFM) identifying groups of sampling sites with similar concentrations of metals in cattail leaves was able to classify study sites according to similar use and potential sources of pollution. Maps prepared for water and bottom sediment showed corresponding groups of sampling sites which suggested similarity of samples features. High concentrations of Fe, Cd, Cu, and Ni were characteristic for industrial areas. Elevated Pb concentrations were noted in regions with intensive vehicle traffic, while high Mn and Zn contents were reported in leaves from the agricultural area. Manganese content in leaves of T. latifolia was high irrespectively of the concentrations in bottom sediments and water so cattail can be considered the leaf accumulator of Mn. Once trained, SOFMs can be applied in ecological investigations and could form a future basis for recognizing the type of pollution in aquatic environments by analyzing the concentrations of elements in T. latifolia.

Bioaccumulation of macro- and trace elements by European frogbit (Hydrocharis morsus-ranae L.) in relation to environmental pollution.

The aim of present study was to investigate the level of trace metals and macroelements in Hydrocharis morsus-ranae collected from regions differing in the degree and type of pollution. Concentrations of 17 macro- and microelements were determined in roots and shoots of European frogbit as well as in water and bottom sediments from 30 study sites. Plants differed in concentrations of elements and bioaccumulation capacity depending on the characteristics of dominant anthropogenic activities in the vicinity of the sampling site. Shoots of H. morsus-ranae growing in the vicinity of organic chemistry plants and automotive industry contained particularly high levels of Cd, Co, and S. Plants from area close to heat and power plant, former ferrochrome industry and new highway, were distinguished by the highest concentrations of Cr, Cu, and Pb. European frogbit from both these regions contained more Fe, Hg, Mn, Ni, and Zn than plants from agricultural and recreational areas. The concentrations of alkali metals and Co, Fe, and N in H. morsus-ranae were elevated in relation to the natural content in macrophytes irrespectively to their content in the environment. Based on the values of Bioaccumulation and Translocation Factors, European frogbit is an accumulator for Co, Cr, Cu, Fe, K, Mn, Ni, Pb, and Zn and a good candidate for phytoremediation of water polluted with Co, Cu, Hg, K, Mn, and Ni. The amount of Co and Mn removed from water and accumulated in the plant biomass during the vegetation season was considerably high.

Trace metal concentrations and their transfer from sediment to leaves of four common aquatic macrophytes.

In the present study, the concentrations of trace and alkali metals in leaves of four common helophytes, Sparganium erectum, Glyceria maxima, Phalaris arundinacea, and Phragmites australis, as well as in corresponding water and bottom sediments were investigated to ascertain plant bioaccumulation ability. Results showed that Mn and Fe were the most abundant trace metals in all plant species, while Co and Pb contents were the lowest. Leaves of species studied differed significantly in respect of element concentrations. The highest concentrations of Mg, Na, Fe, Mn, Cu, Pb, and Ni were noted in S. erectum while the highest contents of Co, Ca, Zn, and Cr in Phalaris arundinacea. Phragmites australis contained the lowest amounts of most elements. Concentrations of Co, Cr, Fe, and Mn in all species studied and Ni in all except for Phragmites australis were higher than natural for hydrophytes. The leaves/sediment ratio was more than unity for all alkali metals as well as for Cu and Mn in Phragmites australis; Cr, Co, and Zn in Phalaris arundinacea; Cr and Mn in S. erectum; and Cr in G. maxima. High enrichment factors and high levels of toxic metals in the species studied indicated a special ability of these plants to absorb and store certain non-essential metals and, consequently, their potential for phytoremediation of contaminated aquatic ecosystems.

Accumulation and distribution of macroelements in the organs of Phalaris arundinacea L.: Implication for phytoremediation.

The aim of this study was to assess nutrient and alkali metal accumulation and their distribution in the organs of Phalaris arundinacea and relations between environmental macroelement concentrations and accumulation in plant tissues. The content of N, P, K, Ca, Mg and Na in water, bottom sediments and different organs of Phalaris arundinacea from the Bystrzyca River (Lower Silesia) was determined. The organs of the reed canary grass contained relatively high amounts of macroelements and differed significantly in their accumulation. All macroelements other than Na were accumulated in the highest amounts in aboveground, photosynthetic tissues. Phalaris arundinacea is an Na and Ca excluder plant and an N, P, Mg and K accumulator. Transport efficiency from bottom sediments to plant roots was higher than between plant organs. Nitrogen, P and K are taken up actively while Ca passively. The high translocation ratio of nutrients, particularly for Ca, Mg, K and N, makes the reed canary grass suitable for nutrient phytoextraction from water and bottom sediments of eutrophic lakes and rivers. Bottom sediments can be considered the primary source of Ca for Phalaris arundinacea.

Macro- and microelement distribution in organs of Glyceria maxima and biomonitoring applications.

The content of nutrients (N, P, K, Ca and Mg) and of trace metals (Fe, Cu, Mn, Zn, Pb, Cd, Co and Ni) in water, bottom sediments and various organs of Glyceria maxima from 19 study sites selected in the Jeziorka River was determined. In general, the concentrations of nutrients recorded in the plant material decreased in the following order: leaf>root>rhizome>stem, while the concentrations of the trace elements showed the following accumulation scheme: root>rhizome>leaf>stem. The bioaccumulation and transfer factors for nutrients were significantly higher than for trace metals. G. maxima from agricultural fields was characterised by the highest P and K concentrations in leaves, and plants from forested land contained high Zn and Ni amounts. However, the manna grass from small localities showed high accumulation of Ca, Mg and Mn. Positive significant correlations between Fe, Cu, Zn, Cd, Co and Ni concentrations in water or sediments and their concentrations in plant indicate that G. maxima may be employed as a biomonitor of trace element contamination. Moreover, a high degree of similarity was noted between self-organizing feature map (SOFM)-grouped sites of comparable quantities of elements in the water and sediments and sites where G. maxima had a corresponding content of the same elements in its leaves. Therefore, SOFM could be recommended in analysing ecological conditions of the environment from the perspective of nutrients and trace element content in different plant species and their surroundings.