Biological Pollutants: Alien Fishes in Mountain Lakes

Many lakes in the national parks of the Canadian Rockies were stocked with alien fish species in the early to mid 20th century. Changes to Parks Canada's mandate require the original communities of these lakes to be restored. We document the changes to invertebrate communities caused by the stocking of alien fishes into three fishless alpine lakes, and describe the results of two restoration experiments, one the reintroduction of Hesperodiaptomus arcticus, a planktonic predator that had been eliminated from Snowflake Lake by stocked fish, and the other the removal of brook trout (Salvelinus fontinalis) from Bighorn Lake. In both cases, there were great changes to the zooplankton communities, which required several years to complete, probably because of the cold water and unproductive nature of the lakes. Many of the invertebrate species extirpated by stocked alien fishes co-exist with native fish species in nearby lakes. Possible reasons are discussed.     

Fish Stomachs as a Biomonitoring Tool in Studies of Invertebrate Recovery

High mortality rates due to predation from fish may reduce densities of preferred prey animals. Predation may also depress the rate of recovery from environmental stress. In an alpine ecosystem damaged by acidification, we compared three different techniques of monitoring the recovery of two large species of crustaceans, the amphipod Gammarus lacustris and the notostrachan Lepidurus arcticus. The methods used were: (1): benthic littoral kick samples, (2): artificial substrate in the form of jute bags, (3): examination of brown trout stomachs. The monitoring took place in two limed lakes at the Hardangervidda mountain plateau in Central Norway, L. Svartavatn and L. Svartavasstjørni. Brown trout, Salmo trutta, is the only fish species in the lakes. Liming as a water quality improvement measure was started in 1994. All stomach samples were negative with respect to Gammarus and Lepidurus during the period 1987–1998. In 1999, the first records of both species were done in trout stomachs collected from Lake Svartavatnet. In Lake Svartavasstjørni, Lepidurus and Gammarus reappeared in fish stomachs in 2001 and 2002, respectively. During the period of monitoring, no records of these crustaceans were done in benthic samples and on artificial substrate in any of the two lakes. In an unacidified reference site, Lake Skiftesjøen, both benthic samples and the jute bags indicated a dense population of Gammarus. Our results strongly indicate that studies of fish stomachs are the best method for monitoring low-density populations of attractive fish food animals.     

Response of Drinking-water Reservoir Ecosystems to Decreased Acidic Atmospheric Deposition in SE Germany: Signs of Biological Recovery

Strongly decreasing atmospheric emissions and acidic deposition during the 1990s have initiated chemical reversal from acidification in several drinking-water reservoirs of the Erzgebirge, SE Germany. We studied responses of phytoplankton, zooplankton and fish stocks in five reservoirs and at enclosure scale after experimental neutralization of 1,200 m³ of lake water. About 4 months after this treatment, diatoms and cryptomonads replaced the predominating chrysophytes and dinoflagellates. The colonization by acid-sensitive species of green algae, cryptomonads, rotifers and Cladocera (e.g. Bosmina longirostris) is explained by the occurrence of dormant stages or by survival of individuals in very low abundances. Analogous to the enclosure experiment, three reservoirs showed significantly (p < 0.01) falling trends of chlorophyll a and phytoplankton biovolume, mainly due to the decline of dinoflagellates. Picoplankton and diatoms increased slightly in two reservoirs. The zooplankton communities were dominated by rotifers and small Cladocera. Representatives of the genus Daphnia were lacking. Two reservoirs were re-colonized by zooplanktivorous fish populations of either perch (Perca fluviatilis) or sunbleak (Leucaspius delineatus). The latter exhibited extremely high fluctuating abundance and biomass and even suffered from a population crash. This natural mortality was caused by a limited food supply. Hence, severe top-down control may delay the recovery of larger zooplankton species like daphnids. Fishery management comprising the introduction of predatory fishes can help to control zooplanktivorous fish populations and to prevent their mass mortality.     

Ecological Integrity Assessment of Lakes Using Fish Communities: An Example from Traunsee Exposed to Intensive Fishing and to Effluents from the Soda Industry

In order to analyse potential influences of soda industryeffluents on the ecological integrity of Traunsee (TS) weinvestigated the fish community of the lake in comparison witha reference lake (Hallstättersee HS) and used a reconstructionfrom the (older) literature concerning the original speciescomposition of Traunsee. Published `Index of Biotic Integrity(IBI)' metrics were considered to be of limited value due tothe relatively low species number in the oligotrophic, Alpinelake. Therefore we included, in addition to speciescomposition, studies on egg distribution, larval fishdensities, life-history parameters (i.e. growth, maturity,fecundity, age and size composition), stress levels and heavymetal content of the dominant whitefish (Coregonuslavaretus), as well as overall fish density and biomass (usinghydroacoustics) to assess the ecological status of the fishcommunity. Two of the original 18 species have disappearedfrom the lake, presumably in connection with the introductionof non-native eel (Anguilla anguilla) and theconstruction of a power plant in the outflow. Silt from grindedlimestone together with highly alkaline pore waters is emittedvia industrial wastewater from Sodaworks and covers part of thelake bottom. We observed that eggs of whitefish were spawnedmainly in the main inflowing river and close to the shore, thusavoiding the silty areas and making the anticipated damage tothe reproductive potential of whitefish neglectable. This wascorroborated by larval surveys done weekly on both lakes fromJanuary to May, which showed halve the density of whitefishlarvae in TS compared to HS. Estimates of potentially spawningfish from hydroacoustic surveys resulted in a ratio of 1(TS) :3 (HS). Analysis of whitefish revealed that they are growingfaster in TS and have higher fecundity leading to somecompensation of lower abundance. High levels of fishing in TSmight have led to this pattern and to depressed yields asindicated by the age composition. Level of oxidative stress andheavy metal content were not discernible from the referencelake. Therefore we concluded that negative impacts on theecological status of the fish community resulted from fisheriesmismanagement and a power plant situated in the outflow of thelake, considered to have damaged spawning places for somespecies, but not from soda industry effluents.     

Effects of Liming on the Aquatic Fauna in a Norwegian Watershed: Why Do Crustaceans and Fish Respond Differently?

We studied the effects of liming on fish and crustaceans in a watershed which is in a region known to have one of the highest diversity of aquatic biota in Norway. This watershed, Enningdal, is shared between Norway (1/3) and Sweden (2/3) and includes 61 lakes  >  1.0 ha in Norway. Liming started on a large scale in the 1980s. Currently, a total of 26 of lakes (43%) are limed, covering 93% of the total lake area. The mean value ± S.D. of pH and the concentration of inorganic labile Al in these lakes is 6.62 ± 0.35 and 3 ± 4 μg l⁻¹, respectively. Historical data of fish communities have been obtained from surveys, while test-fishing and sampling of crustaceans were conducted in 24 lakes in recent years (2002–2004). The present study shows that crustaceans to a greater extent than fish has responded to improved water quality after more than 20 years of liming. Of a total of 120 fish populations, 42 (35%) have gone extinct. Only five of the lost fish populations (12%) have been re-established, all due to human re-introductions. Physical barriers are considered to be the main factor preventing fish from invading limed lakes. In contrast, crustaceans have been re-established in most limed lakes. This may be mainly due to their good spreading capacity. However, they might also have survived in refuges within the watershed, or as resting-eggs in the sediment.     

Impact of Eco-restoration on the Biodiversity of Sundarbans Mangrove Ecosystem, India

A comprehensive study on biodiversity and environmental characteristics of three different selected study sites located on different estuarine networks viz. Matla, Saptamukhi, and Hooghly on eastern, central, and western regions, having different environmental features of Sundarbans Mangrove Ecosystem, India, a World Heritage Site, was conducted through six seasons of consecutive 2 years. The different sites understudy have shown variable species composition. Special emphasis was made to record the population structure of benthic fauna, which exhibited maximum density during pre-monsoon followed by monsoon and post-monsoon. Physicochemical parameters displayed a wide range of fluctuation through different seasons and also revealed differences among different study sites. Biotic community structures of different study sites have been analyzed using different community indices like similarity index, dominance index, diversity index, and evenness index. Moreover, in order to evaluate the environmental stress on the environmental health of this dynamic mangrove ecosystem of global importance, species pollution value and community pollution value have been deduced as a new model of biotic indices based on the distribution patterns of both zooplanktons and benthic fauna. Canonical correspondence analysis revealed the cumulative influence of a group of environmental parameters on the abundance of different components of biodiversity. The study site II (Saptamukhi), encircled by undisturbed mangrove islands, revealed the least pollution stress and higher biological diversity followed by Jharkhali (study site I), which is in the process of eco-restoration and Bokkhali (study site III), which has been under anthropogenic stress especially from ecotourism.     

Protozooplankton in the Deep Oligotrophic Traunsee (Austria) Influenced by Discharges of Soda and Salt Industries

Traunsee is a deep oligotrophic lake in Austria characterised by an artificial enrichment of chloride in the hypolimnion (up to 170 mg L^-1) caused by waste disposal of soda and salt industries. Protists were collected monthly over one year, observed alive and after Quantitative Protargol Staining (ciliates) or via epifluorescence microscopy (heterotrophic flagellates). Three sites within the lake (0–40 m depths) were compared to deeper water layers from 60–160 m depths where chloride concentrations and conductivity were increased. In addition, we observed the protozooplankton of two neighbouring lakes, i.e. reference systems, during one sampling occasion. In Traunsee the abundance of ciliates was low (200–36 600 cells L^-1) in contrast to high species diversity (at least 60 different species; H_S = 2.6) throughout the year. The main pelagic species in terms of abundance were small oligotrichs and prostomatids like Rimostrombidium brachykinetum/hyalinum, Balanion planctonicum and Urotricha spp. throughout the investigation period. Among free-living heterotrophic flagellates, which occurred at densities of 40–2800 cells mL^-1, small morphotypes dominated in the pelagial. No differences at the community level between the three lakes could be observed and pelagic ciliates and flagellates seemed not to be affected by increased chloride concentrations or by enhanced conductivity.     

Microbial responses to in situ chemical oxidation,six‐phase heating,and steam injection remediation technologies in groundwater

The evaluation of microbial responses to three in situ source removal remedial technologies—permanganate‐based in situ chemical oxidation (ISCO), six‐phase heating (SPH), and steam injection (SI)—was performed at Cape Canaveral Air Station in Florida. The investigation stemmed from concerns that treatment processes could have a variety of effects on the indigenous biological activity, including reduced biodegradation rates and a long‐term disruption of community structure with respect to the stimulation of TCE (trichloroethylene) degraders. The investigation focused on the quantity of phospholipid fatty acids (PLFAs) and its distribution to determine the immediate effect of each remedial technology on microbial abundance and community structure, and to establish how rapidly the microbial communities recovered. Comprehensive spatial and temporal PLFA screening data suggested that the technology applications did not significantly alter the site's microbial community structure. The ISCO was the only technology found to stimulate microbial abundance; however, the biomass returned to predemonstration values shortly after treatment ended. In general, no significant change in the microbial community composition was observed in the SPH or SI treatment areas, and even small changes returned to near initial conditions after the demonstrations. © 2004 Wiley Periodicals, Inc.     

Effects of Liming and Ash Application on Below Ground Ectomycorrhizal Community Structure in Two Norway Spruce Forests

The effect of lime and ash additions upon the below ground ectomycorrhizal communities was studied at two spruce forest sites, Horröd and Hasslöv, in Southern Sweden. At Hasslöv, fifteen years after the addition of 8.75 ton ha^-1 of dolomite, the species richness of the mycorrhizal community was unchanged. However, the liming resulted in an almost total replacement of species normally found under the site conditions, with only three morphotypes from a total of 24 distinguished being common to both the control and limed plots. At Horröd, four years after the application of 3.25 ton ha^-1 crushed lime, there was a significant reduction in the number of species recorded. This was not a result of a reduction in root tips sampled, since there was no significant treatment effect upon root tip abundance. Instead, it appeared that the less common species present in the control plots had been lost following liming. At the same site, the addition of 4.28 ton ha^-1 of wood ash had little effect upon the mycorrhizal community as a whole, with only small changes recorded in the abundance of a small number of species. This study highlights the urgent need for additional data on the temporal and load response of ectomycorrhizal fungi to the addition of lime. This information is vital in view of the proposed widespread use of lime as a counter measure to soil acidification.     

Assessment of the Ecological Integrity of Traunsee (Austria) Via Analysis of Sediments and Benthic Microbial Communities

Since nearly one hundred years Traunsee experiences the import of tons of liquid and solid waste originating from salt and soda production. Today, the lake exhibits chloride concentrations of up to 170 mg L^-1 and 19% of the lake floor are directly or indirectly influenced by industrial deposits (ID). Based on the comparison of several microbial parameters in unaffected, directly affected and intermediate lake bottom sediments, the ecological integrity of the lake was evaluated. The highly alkaline ID, which were exclusively colonized by microorganisms, harbored a bacterial community reduced by a factor of 10 in abundance and biomass compared to undisturbed sediment areas within the lake. The bacterial community of ID was furthermore characterized by a reduced content of actively respiring cells (INT-formazan reduction), a lower frequency of dividing cells (FDC) and a significantly reduced cell and biomass production. A 80 to 90% reduction in carbon recycling is estimated for the area exclusively covered by ID. Protists, although occasionally absent from the industrial sediments, were in general found to be less sensitive to the contaminant stress. Differences in alkalinity and dissolved organic carbon (DOC) concentrations of sediment porewaters as well as the total organic content and C/N ratios of sediments partly explain the microbial pattern observed at the various sampling sites. Possible consequences of the continuous industrial tailings for the whole lake ecosystem and the validation of the ecological integrity are discussed.     

Recovery of Acidified Lakes: Lessons From Sudbury, Ontario, Canada

Over 7,000 lakes around Sudbury, Ontario, Canada were acidified by S deposition associated with emissions from the Sudbury metal smelters and more distant S sources. Air pollution controls have led to widespread changes in damaged Sudbury lakes, including increased pH and decreased concentrations of SO₄, metals and base cations. While chemical improvements have often been substantial, many lakes are still acidified, although water quality recovery is continuing. Biological recovery has been observed in some lakes among various groups of organisms including fish, zooplankton, phytoplankton and zoobenthos. Generally, however, biological recovery is still at an early stage. Lakes around Sudbury are also showing that the recovery of acid-damaged lakes is closely linked to the effects of other major environmental stressors such as climate change, base cation depletion and UV-B irradiance. Future studies of the recovery of acid-damaged lakes around Sudbury, and in other regions, will need to consider the interactions of these and other stressors.     

Invasives, Introductions and Acidification: The Dynamics of a Stressed River Fish Community

We describe the development of the fish community in the acidified and limed river Litleåna in southern Norway, and describe how chemical restoration, compensatory introductions of exotics, and accidental invasion of exotics interact to influence the population of the naturally occurring brown trout (Salmo trutta). The river Litleåna is a tributary to the river Kvina in Vest-Agder County, southern Norway. During the years 1996–2004, annual mean pH was 4.9–5.0 and 6.1–6.4 above and below the liming facility, which was installed in 1994. Originally, brown trout was the only fish species in the river, but brook trout (Salvelinus fontinalis) have been intentionally introduced, whereas European minnow (Phoxinus phoxinus) was introduced by accident. Fish densities were recorded by means of electrofishing annually over the ten year period 1995–2004. Although close to extinction before liming was initiated, brown trout fry densities increased from 1995 to 1999, with subsequent varying densities. There has been a simultaneous major increase in the occurrence and density of European minnow since 1997. Our results show that both brown trout and European minnow increase after liming. Minnow densities are negatively affected by low pH episodes in the river. The growth rates of brown trout fry are negatively correlated to minnow densities, indicating competition between the species. Brook trout densities have decreased since liming started, and during the brown trout recovery.     

The importance of chemical buffering for pelagic and benthic colonization in acidic waters

In poorly buffered areas acidification may occur for two reasons: through atmospheric deposition of acidifying substances and – in mining districts – through pyrite weathering. These different sources of acidity lead to distinct clearly geochemistry in lakes and rivers. In general, the geochemistry is the major determinant for the planktonic composition of the acidified water bodies, whereas the nutrient status mainly determines the level of biomass. A number of acidic mining lakes in Eastern Germany have to be neutralized to meet the water quality goals of the European Union Directives and to overcome the ecological degradation. This neutralization process is limnologically a short-term maturation of lakes, which permits biological succession to overcome two different geochemical buffer systems. First, the iron buffer system characterizes an initial state, when colonization starts: there is low organismic diversity and productivity, clear net heterotrophy in most cases. Organic carbon that serves as fuel for the food web derives mainly from allochthonous sources. In the second, less acidic state aluminum is the buffer. This state is found exceptionally among the hard water mining lakes, often as a result of deposition of acidifying substances onto soft water systems. Colonization in aluminum-buffered lakes is more complex and controlled by the sensitivity of the organisms towards both, protons and inorganic reactive aluminum species. In soft-water systems, calcium may act as antidote against acid and aluminum; however, this function is lost in hard water post mining lakes of similar proton concentrations. Nutrient limitations may occur, but these do not usually control qualitative and quantitative plankton composition. In these lakes, total pelagic biomass is controlled by the bioavailability of nutrients, particularly phosphorus.     

The Svalbard Intertidal Zone: A Concept for the Use of GIS in Applied Oil Sensitivity,Vulnerability and Impact Analyses

Historical oil spills have shown that environmental damage on the seashore can be measured by acute mortality of single species and destabilisation of the communities. The biota, however, has the potential to recover over some period of time. Applied to the understanding of the fate of oil and population and community dynamics, the impact can be described by the function of the following two factors: the immediate extent and the duration of damage. A simple and robust mathematical model is developed to describe this process in the Svalbard intertidal. Based on the integral of key biological and physical factors, i.e., community specific sensitivity, oil accumulation and retention capacity of the substrate, ice-cover and wave exposure, the model is implemented by a Geographical Information System (GIS) for characterisation of the habitat’s sensitivity and vulnerability. Geomorphologic maps and georeferenced biological data are used as input. Digital maps of intertidal zone are compiled, indicating the shoreline sensitivity and vulnerability in terms of coastal segments and grid aggregations. Selected results have been used in the national assessment programme of oil development in the Barents Sea for priorities in environmental impact assessments and risk analyses as well as oil spill contingency planning.     

Mercury and Organochlorine Contamination in Brown Trout (Salmo Trutta) and Arctic Charr (Salvelinus Alpinus) from High Mountain Lakes in Europe and the Svalbard Archipelago

High concentration of Hg, less volatile PCB congeners and p,p-DDE in Arctic charr from an arctic lake was mainly causedby biomagnification in the food chain where cannibalism was thedriving force. We suggest that low sediment fluxes of Hg, low net production of methyl mercury, and short food chains excludingpiscivory explain the low levels of Hg in the invertebrate feeding fish population in five European high mountain lakes.Concentrations of less volatile PCB congeners in insectivorous fish populations from the European high mountain lakes were mainly influenced by fish age and atmospheric deposition, indicated by the sediment inventory. Atmospheric deposition influenced by local sources may explain the higher concentrationsof pesticides (p,p-DDT, p,p-DDE and -HCH) observedin fish from the Pyrenees compared to the other sites. Theconcentrations of Hg and organochlorines did not exceedthe guidelines for fish consumption, except for Hg levelsin the oldest fish from the arctic lake.     

Metal Concentrations in Pore Water of the Lusatian Lignite Mining Sediments and Internal Metal Distribution in Juncus bulbosus

The aim of this study was to determine a suite of four metals (Fe, Mn, Zn, Cu) in the sediment, porewater and a pioneer plant (Juncus bulbosus) of Lusatian lignite mining lakes in eastern Germany. An attempt was made to understand the factors which affect element concentrations in the above- and below-ground biomass of Juncus bulbosus in an extreme environment. Water samples, sediments, porewater and plant material collected from two different mining lakes dominated by Juncus bulbosus species were analyzed for their elemental content. Additionally, scanning electron microscopy (SEM) and an energy-dispersive X-ray (EDX) detector were used to follow the internal metal distribution in the roots of Juncus plant. Results showed that sediment and porewater element concentrations in the lakes decreased in the order Fe > Mn > Zn and Cu. All the four elements were higher in the roots than in above-ground tissues, suggesting that iron plaque induced on roots under anaerobic conditions served as a metal reservoir, but not as an ultimate mechanism to control metal concentrations in the above-ground tissues. SEM and EDX analyses revealed that the rhizodermis, exodermis and endodermis cells regulate the traffic of transition metals and therefore avoid excess levels that are toxic to the plant in acidic mining-impacted lake sediments.     

Assessment of Ecological Integrity from Environmental Variables in an Impacted Oligotrophic,Alpine Lake: Whole Lake Approach Using 3d-Spatial Heterogeneity

The ecological integrity of a lake as a whole can only beassessed through an adequate sampling strategy. Spatialheterogeneity of phytoplankton as well as vertical andhorizontal variability of physical and chemical variables wereestimated from 57 stations at four seasons differing in theirhydrological regime. Resolution of grid positions, located byGPS, was 250 m near the impact site, 500 m for the southernpart of the lake, and 1000 m in the northern part. Data areanalysed by conventional gridding methods as well as in threedimensions with a novel GIS-technique. Horizontal large scaledifferences in several variables are associated withhydrological situations. Local variability in the southern baywas due to input of industrial tailings at times. Spatialvariation of phytoplankton biomass estimated as chlorophyll-aand relevant associated environmental variables were analysedusing a graphical multimetric approach. With this technique,the directly impacted area can be evaluated relative to theremaining part of the lake. The lake is then compared with tworeference lakes, one within the same catchement, the other ina different water-shed. An index of ecological integrity wasdeveloped describing multimetric intra- and interspecific lakevariability. The final index was used to describe the statusof lake water quality relative to a `undisturbed' referencelake. Results showed that Traunsee is ecologically intactalthough its chemistry differs substantially from an`external' reference.     

Finnish Lake Survey: The Role of Catchment Attributes in Determining Nitrogen, Phosphorus, and Organic Carbon Concentrations

This study is based on a Finnish lake survey conducted in 1995, a dataset of 874 statistically selected lakes from the national lake register. The dataset was divided into subgroups to evaluate lake water-catchment relationships in different geographical regions and in lakes of different size. In the three southernmost regions, the coefficients of determination in multiple regression equations varied between 0.40 and 0.53 for total nitrogen (TN) and between 0.37 and 0.53 for total phosphorus (TP); the best interpreters were agricultural land and water area in the catchment. In the two northernmost regions, TN concentrations in lake water were best predicted by the proportion of peatlands in the catchment, the catchment slope, and TP concentrations by lake elevation and latitude. Coefficients of determination in multiple regression equations in these northern regions varied between 0.39 and 0.67 for TN and between 0.41 and 0.52 for TP. For all the subsets formed, the best coefficients of determination explaining TN, TP, and total organic carbon (TOC) were obtained for a subset of large lakes (>10 km²), in which 72–83% of the variation was explained. This was probably due to large heterogeneous catchments of these lakes.     

Restoration of a Small High Mountain Lake after Recent Tourist Impact: The Importance of Limnological Monitoring and Palaeolimnology

The natural Park of Peñalara consists of a small mountainousarea near Madrid and includes a series of water bodies (fromsmall mountain lakes to temporary ponds and peat bogs), the mostknown of them being the so-called `Laguna Grande dePeñalara'. Due to growing numbers of visitors theenvironmental conditions of this lake started to decline in theearly 1970s because of: (1) the start of severe soil erosionprocesses; (2) the increase of nutrient load; and (3) theintroduction of a non-native fish species. Since the area wasprotected in 1990, several conservation and restoration projectsincluded in an integrated management plan have been developed. Here we summarise some of the results of these efforts: (1) controlled access of livestock and visitors to the area; (2) palaeolimnology studies aimed at inferring recent changes in thewatershed; and (3) monitoring of the limnological features of thesystem. Restoration of this lake and its watershed is intendedto serve as a model for the management of other severely alteredhigh mountain lakes.     

Zinc,lead, and cadmium tolerance and accumulation in Cistus libanotis,Cistus albidus,and Cistus salviifolius: Perspectives on phytoremediation

Heavy metal contamination is of particular concern for human health and the environment. Phytoremediation is an emerging cost‐effective strategy to remediate heavy metal contaminated soil. However, this technique is limited by the small number of plants that are tolerant to heavy metals and are also accumulators. This study assayed zinc, lead, and cadmium tolerance and accumulation in Cistus libanotis, Cistus albidus, and Cistus salviifolius. The plants were cultivated in hydroponic conditions and exposed to different concentrations of Pb(NO₃)₂ (100 and 200 µM), ZnSO₄ (100 and 200 µM), or CdCl₂ (10 and 20 µM) for 3 weeks. Plant biomass and metal accumulation in roots and aboveground parts varied greatly among the species. All three species appeared to be sensitive to Zn. However, C. albidus displayed strong tolerance to Pb and accumulated large quantities of Pb and Cd in its roots. C. libanotis accumulated large quantities of Pb and Cd in its aboveground parts. C. libanotis can thus be classified as a Pb and Cd accumulator species. The study results show that C. albidus is suitable for phytostabilization of Pb‐contaminated soils, while C. libanotis can be used for phytoextraction of both Pb and Cd.