Soil Nitrogen Fertilization Effects on Phytoextraction of Cadmium and Lead by Tobacco (Nicotiana tabacum L.)

A greenhouse experiment using 24 plastic pots filled with 6 kg of Pb- and Cd-contaminated soil was carried out. In all 24 pots, soils were heavy metal–contaminated with 10 mg Cd kg^?1 soil and 500 mg of Pb kg^?1 soil by using CdCl and PbNO₃. Two-month-old tobacco (Nicotiana tabacum L.) plants were used to extract these heavy metals. Results showed that tobacco is able to remove Cd and Pb from contaminated soils and concentrate them in its harvestable part, that is, it could be very useful in phytoextraction of these heavy metals. Increasing additions of ammonium nitrate to soil (50, 100, and 150 mg N kg^?1 soil) significantly (p ≤ .05) increased aboveground Cd and Pb accumulation during a 50-day experimental period, whereas increasing additions of urea to soil (50 and 100 mg N kg^?1 soil) did not show these effects at the same significance levels. Increasing additions of ammonium nitrate to soil shows as dry matter increases, both accumulated Cd and accumulated Pb also increase when tobacco plants are growing under Pb- and Cd-contaminated soil conditions. Higher Pb concentrations depress Cd/Pb ratios for concentrations and accumulations, suggesting that Pb negatively affects Cd concentration and/or accumulation.     

Modeling of Pb(II) adsorption by a fixed-bed column

Removal of Pb(II) from an aqueous environment using biosorbents is a cost-effective and environmentally benign method. The biosorption process, however, is little understood for biosorbents prepared from plant materials. In this study, the biosorption process was investigated by evaluating four adsorption models. A fixed-bed column was prepared using a biosorbent prepared from the aquatic plant Hydrilla verticillata. The effect of bed height and flow rate on the biosorption process was investigated. The objective of the study was to determine the ability of H. verticillata to biosorb Pb(II) from an aqueous environment and to understand the process, through modeling, to provide a basis to develop a practical biosorbent column. Experimental breakthrough curves for biosorption of 50 mg L^?1 aqueous Pb(II) using a fixed-bed column with 1.00 cm inner diameter were fitted to the Thomas, Adams-Bohart, Belter, and bed depth service time (BDST) models to investigate the behavior of each model according to the adsorption system and thus understand the adsorption mechanism. Model parameters were evaluated using linear and nonlinear regression methods. The biosorbent removed 65% (82.39 mg g^?1 of biosorbent) of Pb(II) from an aqueous solution of Pb(NO₃)₂ at a flow rate of 5.0 ml min^?1 in a 10 cm column. Na₂CO₃ was used to recover the adsorbed Pb(II) ions as PbCO₃ from the biosorbent. The Pb(II) was completely desorbed at a bed height of 10.0 cm and a flow rate of 5.0 ml min^?1. Fourier transform infrared (FT-IR) analysis of the native biosorbent and Pb(II)-loaded biosorbent indicated that the hydroxyl groups and carboxylic acid groups were involved in the metal bonding process. The FT-IR spectrum of Pb(II)-desorbed biosorbent showed an intermediate peak shift, indicating that Pb(II) ions were replaced by Na⁺ ions through an ion-exchange process. Of the four models tested, the Thomas and BDST models showed good agreement with experimental data. The calculated bed sorption capacity N₀ and rate constant k_a were 31.7 g L^?1 and 13.6 × 10^?4 L mg^?1 min^?1 for the C_t/C₀ value of 0.02. The BDST model can be used to estimate the column parameters to design a large-scale column.     

Contrasting the Pb (II) and Cd (II) tolerance of Enterobacter sp. via its cellular stress responses

Successful application of microorganisms to heavy metal remediation depends on their resistance to toxic metals. This study contrasted the differences of tolerant mechanisms between Pb²⁺ and Cd²⁺ in Enterobacter sp. Microbial respiration and production of formic acid showed that Enterobacter sp. had a higher tolerant concentration of Pb (>1000 mg l⁻¹) than Cd (about 200 mg l⁻¹). Additionally, SEM confirmed that most of Pb and Cd nanoparticles (NPs) were adsorbed onto cell membrane. The Cd stress, even at low concentration (50 mg l⁻¹), significantly enlarged the sizes of cells. The cellular size raised from 0.4 × 1.0 to 0.9 × 1.6 μm on average, inducing a platelet-like shape. In contrast, Pb cations did not stimulate such enlargement even up to 1000 mg l⁻¹. Moreover, Cd NPs were adsorbed homogeneously by almost all the bacterial cells under TEM. However, only a few cells work as ‘hot spots’ on the sorption of Pb NPs. The heterogeneous sorption might result from a ‘self-sacrifice’ mechanism, i.e., some cells at a special life stage contributed mostly to Pb sorption. This mechanism, together with the lower mobility of Pb cations, caused higher microbial tolerance and removal efficiency towards Pb²⁺. This study sheds evident contrasts of bacterial resistance to the two most common heavy metals.     

Reliable classification of six Pi M subtypes by separator isoelectric focusing.

For the first time, segregation of three common PiM alleles in family material is verified by application of separator isoelectric focusing. A new nomenclature system for the Pi M subtypes is used, whereby the common subtypes are designated according to their physicochemical properties; the most anodal type is called Pi M1, the intermediary one Pi M2, and the most cathodal variant Pi M3 (previously called Pi M2). Pi gene frequencies from Finnish, Dutch and Black populations are presented. The PiM2 allele was rather high in Finns (0.12) but low (0.04) in the West African Bozo. The PiM3 was found with a frequency of 0.13 in Dutch, 0.08 in Finns and 0.02 in Bozo. A previous Finnish sample was retested with the new subtyping method and the six-subtype distribution was found to be in good Hardy-Weinberg equilibrium. The validity of the Pi polymorphism for population genetics, linkage analysis and parentage testing is discussed.     

Rapid detection of glyoxalase I (GLO) on cellulose acetate gel and the distribution of GLO variants in a Dutch population

Summary A rapid electrophoretic procedure is described for detecting the human red cell glyoxalase I variants (GLO 1, GLO 2-1, and GLO 2) on cellulose acetate gel (cellogel) on which the sites of enzymed activity are visualized as purple bands against white background. The frequency of GLO ¹ gene in a Dutch population living in and around Leiden was found to be 0.4544.     

A new insight into lead (II) tolerance of environmental fungi based on a study of Aspergillus niger and Penicillium oxalicum

Environmental microorganisms have been widely applied in heavy metal remediation. This study explored the mechanisms of lead tolerance of two typical filamentous fungi, Aspergillus niger and Penicillium oxalicum. It is shown that the mechanisms of reducing Pb toxicity by these two fungi have three major pathways. The secreted oxalic acid can react with Pb (II) to form insoluble Pb minerals, primarily lead oxalate. Then, the enhanced biosorption via forming new border of cell wall prevents the transportation of Pb (II) into hypha. In addition, the fungal activity could be maintained even at high Pb concentration due to the intracellular accumulation. It was confirmed that A. niger has the higher Pb tolerance (up to 1500 mg l⁻¹ Pb level) compared with P. oxalicum (up to 1000 mg l⁻¹). Meanwhile, Pb levels below 1000 mg l⁻¹ partially stimulate the bioactivity of A. niger, which was confirmed by its elevated respiration (from 53 to 63 mg C l⁻¹ medium h⁻¹). This subsequently enhanced microbial functions of A. niger to resist Pb toxicity. A better understanding of Pb tolerance of these two fungi sheds a bright future of applying them to remediate lead-contaminated environments.     

Biosorption and Desorption of Lead(II) by Hydrilla verticillata

The potential of nonliving biomass of Hydrilla verticillata to adsorb Pb(II) from an aqueous solution containing very low concentrations of Pb(II) was determined in this study. Effects of shaking time, contact time, biosorbent dosage, pH of the medium, and initial Pb(II) concentration on metal-biosorbent interactions were studied through batch adsorption experiments. Maximum Pb(II) removal was obtained after 2 h of shaking. Adsorption capacity at the equilibrium increased with increasing initial Pb(II) concentration, whereas it decreased with increasing biosorbent dosage. The optimum pH of the biosorption was 4.0. Surface titrations showed that the surface of the biosorbent was positively charged at low pH and negatively charged at pH higher than 3.6. Fourier transform infrared (FT-IR) spectra of the biosorbent confirmed the involvement of hydroxyl and C?O of acylamide functional groups on the biosorbent surface in the Pb(II) binding process. Kinetic and equilibrium data showed that the adsorption process followed the pseudo-second-order kinetic model and both Langmuir and Freundlich isothermal models. The mean adsorption energy showed that the adsorption of Pb(II) was physical in nature. The monolayer adsorption capacity of Pb(II) was 125 mg g^?1. The desorption of Pb(II) from the biosorbent by selected desorbing solutions were HNO₃ > Na₂CO₃ > NaOH > NaNO₃.     

Carbon and Nitrogen Mineralization of Lead Treated Soils in the Eastern Mediterranean Region,Turkey

The aim of this study was to determine the first effect of lead on microbial activity in soil. The study was carried out in the soil samples from four different radish (Raphanus sativus L. var. radicula, Brassicaceae) fields along the highway in a district (Kadirli, Osmaniye) of the Eastern Mediterranean Region, Turkey. After the calculation of Pb contents, the Pb amounts of the soil samples were brought up to 50 and 100 mg Pb kg^?1 by treatment with Pb(NO ₃ ) ₂ , and the samples for the carbon and the nitrogen mineralization were incubated under controlled conditions (28°C, constant moist). The carbon mineralization was determined by a CO ₂ respiration method for 30 days. The nitrogen mineralization was observed in vitro for 6 weeks. The untreated group was statistically different from the 50 and 100 mg Pb kg^?1 treatments in the aspect of the C(CO ₂ ) outlet during mineralization (P ≤ 0.05), but difference between the 50 and 100 mg Pb kg^?1 treatments was not significant. NH ₄ -N and NO ₃ -N contents of each soil were shown differences between across treatments. Based on these results, it is possible to conclude that the addition of 50 and 100 mg Pb kg^?1 provided a toxic effect threshold for the microbial activity into 30 days.     

Scandinavian limnochronology of sediments and heavy metals

Sediment and peat accumulation rates as well as heavy metal fluxes are examined in Scandinavian lakes, marine coasts and peatlands. Modern accumulation rates are determined using Pb-210 and other chronological tools. Mean deposition rates in the past 150 ± 20 yrs are 3–95, 40–190 and 1–5 mg·cm^–2·yr^–1 for lakes, marine coasts and peatlands respectively. The Pb-210 fluxes at the investigated sites are quite variable. The lowest values are found for peatlands 0.04–0.20 pCi·cm^–2·yr^–1 while coastal marine environments showed 0.35–0.70 pCi·cm^–2·yr^–1. A wide range of variation of Pb-210 fluxes is obtained for the studied lake sediments 0.01–0.51 pCi·cm^–2·yr^–1.The chronological records of Pb, Zn, Cu, Cd and Hg show that heavy metal fluxes are much higher in coastal marine areas. Inland lakes and ombrotrophic peat-bogs indicate that Pb is introduced exclusively through the atmosphere and decrease exponentially from South to North Scandinavia. However, the other heavy metals are transported to freshwater systems by different hydrologic and atmospheric processes. Zn and Fe exhibit some correlation with lake-drainage area.     

Toxic effects of Pb2+ on the growth and mineral nutrition of signal grass (Brachiaria decumbens) and Rhodes grass (Chloris gayana)

Although grasses are commonly used to revegetate sites contaminated with lead (Pb), little is known regarding the Pb-tolerance of many of these species. Using dilute solution culture to mimic the soil solution, the growth of signal grass (Brachiaria decumbens Stapf cv. Basilisk) and Rhodes grass (Chloris gayana Kunth cv. Pioneer) was related to the mean activity of Pb²⁺ {Pb²⁺} in solution. There was a 50% reduction in fresh mass of signal grass shoots at 5 μM {Pb²⁺} and at 3 μM {Pb²⁺} for the roots. Rhodes grass was considerably more sensitive to Pb in solution, with shoot and root fresh mass being reduced by 50% at 0.5 μM {Pb²⁺}. The higher tolerance of signal grass to Pb appeared to result from the internal detoxification of Pb, rather than from the exclusion of Pb from the root. At toxic {Pb²⁺}, an interveinal chlorosis developed in the shoots of signal grass (possibly a Pb-induced Mn deficiency), whilst in Rhodes grass, Pb²⁺ caused a bending of the root tips and the formation of a swelling immediately behind some of the root apices. Root hair growth did not appear to be reduced by Pb²⁺ in solution, being prolific at all {Pb²⁺} in both species.     

Characterization of Pb and Cd contamination in the feces and feathers of rook (Corvus frugilegus) and the scalp hair of residents in Qiqihar,northeastern China

The concentrations of Pb and Cd, and trace elements (Cu and Zn) in the urban topsoil, rook (Corvus frugilegus) feces and feathers and human scalp hair were analyzed to examine the potential ecological risk posed by Pb and Cd on local residents of Qiqihar City, northeastern China. Results revealed that the Cd concentrations in the topsoil were ranged from 0.14 to 3.55 mg kg^?1 dry weight (dw). The maximal geoaccumulation indices [a value from logarithmic (a measured metal content/1.5 × background content of the metal in this region), introduced by Muller] of Cd exceeded 3.5, which suggested that this region was seriously contaminated by Cd. The corresponding average detectable concentrations in C. frugilegus feathers and feces were 1.38 and 3.97 mg kg^?1 dw for Pb and 1.04 and 0.69 mg kg^?1 dw for Cd. High Pb and Cd concentrations, respectively, ranging from 7.46 to 24.9 mg kg^?1 dw and from 0.35 to 0.92 mg kg^?1 dw were also detected in the human scalp hair samples. These high Pb and Cd concentrations in C. frugilegus and local people were possibly associated with local industrial wastes and vehicle exhausts. The external tissues (feces and feather) of the rook species can be considered as an indicator of potential Cd toxic risk in this species; however, the human scalp hair is not a reliable biomarker for risk of Pb and Cd in the human being. Effective measures should be established to reduce the inputs of Pb and Cd into the urban environment and to protect the health of local people.     

Salivary peroxidase (SAPX): Genetic modification and relationship to the proline-rich (Pr) and acidic (Pa) proteins

There is genetic polymorphism of the peroxidase of human saliva, but not of leukocytes. The phenotypes are determined by autosomal inheritance, the phenotype of fast mobility (SAPX 1) being determined by homozygosity for a recessive gene (SAPX ¹) and the phenotypes of slow mobility (SAPX 2 and SAPX 3) being determined by two different genes, SAPX ² and SAPX ³, with completely dominant expression at the same locus. The phenotypes are modified by varying degrees of endogenous proteolysis. The SAPX 2 and SAPX 3 types appear to be genetically controlled modifications of SAPX 1 rather than different primary gene products, because of their completely dominant inheritance, their larger molecular size compared to SAPX 1, and their dissociation with 2-mercaptoethanol to give SAPX 1. The acidic protein type Pa 1 is always found in association with SAPX 2, and an uncommon variant type Pa 2 is associated with SAPX 3. The most likely hypothesis is that the genes Pa ¹ and Pa ² produce products which modify the SAPX 1 type. When the Pa type is Pa 0, the SAPX phenotype is SAPX 1. Since 2-mercaptoethanol can dissociate the Pa 1 protein into a probable monomeric form, and can dissociate SAPX 2 and SAPX 3 to give SAPX 1, it is probable that Pa 1 and Pa 2 monomers complex with SAPX 1 through disulfide bonds to give SAPX 2 or SAPX 3 types. The frequencies of the genes determining the SAPX types are the same as those for Pa: SAPX ¹ and Pa ⁰=0.787, SAPX ² and Pa ¹=0.208, SAPX ³ and Pa ²=0.005.This study was supported by a grant from the National Institutes of Dental Research (2-RO1-DE-03658-11).     

Red cell glutathione peroxidase (GPX1) variation in Afro-Jamaican,Asiatic Indian,and Dutch populations

Summary A Cellogel procedure for screening the electrophoretic variants of the human red cell glutathione peroxidase (GPX1) was described. Three hundred and ninety eight Dutch persons living in various parts of The Netherlands, 385 individuals born in various states of India, and 72 Jamaicans of African origin livig in Birmingham, UK, were screened for GPX1 variants. The Dutch were monomorphic, while one Afro-Jamaican female and two males and one female of the 116 Punjabis were found to be variants indistinguishable from each other in their pattern of electrophoresis. The clear five banded pattern of the variant indicated that the subunit structure of the human red cell glutathione peroxidase is most probably a tetramer and suggested that the variant is the expression of a heterozygote due to alleles at an autosomal locus. The corresponding phenotype was designated tentatively as GPX1 2-1 and the alleles as GPX1 ^*1 and GPX1 ^*2 respectively. The variant 2-1 was found to be identical to the Thomas variant described by Beutler and West (1974). Thus so far, in addition to the Afro-Americans and Ashkenazi Jews (Beutler et al. 1974), the Punjabis of the Indian subcontinent (this report) were found to exhibit the GPX1 polymorphism due to the GPX1 ^*2 allele. The data discussed in this paper (which included unpublished observations on several African and non-African populations) suggest that the GPX1 ^*2 allele is originally an African variant and hint that the present day Punjabis of Indian subcontinent, like Ashkenazi Jews, are predominantly of Mediterranean origin with some proportion of African ancestry (Mourant et al. 1976).     

Potential of Sonchus Arvensis for the Phytoremediation of Lead-Contaminated Soil

Sonchus arvensis is one of the pioneer plant species that were found in the abandoned Bo Ngam Pb mine in Thailand. S. arvensis was collected from three sites. The highest Pb shoot concentration was 9317 mg kg^?1 and the highest translocation factor (TF) and bioaccumulation factor (BF) values were 2.5 and 6.0, respectively. To investigate Pb uptake capacity of S. arvensis, a hydroponic experiment was performed for 15 d. S. arvensis exposed to 5 mg L^?1 Pb solution had the highest Pb shoot accumulation (849 mg kg^?1). In a pot study, S. arvensis was grown in Pb mine soils amended with organic and inorganic fertilizers for 2 mo. The addition of organic fertilizer to the soil increased plant dry biomass sharply. All treatments with ethylene-diamine-tetra-acetic acid (EDTA) had Pb accumulation in shoots greater than 1000 mg kg^?1 and the highest Pb shoot accumulation was found in S. arvensis grown in soil amended with organic fertilizer and EDTA (1397 mg kg^?1). In a field trial study, S. arvensis was grown at three sites in the mine area for 6 mo. S. arvensis could tolerate a total Pb of 100,000 mg kg^?1 in the soil and accumulated Pb in the shoots up to 3664 mg kg^?1 with high TF (2.19) and BF (2.38) values. These results suggest that S. arvensis is a good candidate for Pb phytoremediation.     

Adsorption of lead(II) from aqueous solution onto Hydrilla verticillata

The adsorption of Pb(II) onto Hydrilla verticillata was examined in aqueous solution with parameters of pH, adsorbent dosage, contact time and temperature. The linear Langmuir and Freundlich models were applied to describe equilibrium isotherms, and both models fitted well. The monolayer adsorption capacity of Pb(II) was found as 104.2 mg/g at pH 4 and 25°C. Dubinin–Radushkevich (D–R) isotherm model was also applied to the equilibrium data. The mean free energy of adsorption (15.81 kJ/mol) indicated that the adsorption of Pb(II) onto H. verticillata may be carried out via chemical ion-exchange mechanism. Thermodynamic parameters, free energy (ΔG ⁰), enthalpy (ΔH ⁰) and entropy (ΔS ⁰) of adsorption were also calculated. These parameters showed that the adsorption of Pb(II) onto H. verticillata was a feasible, spontaneous and exothermic process in nature. The influence of Cd²⁺, Cu²⁺ and Ni²⁺ on adsorption of Pb²⁺ onto H. verticillata was studied, too. In the investigated range of operating conditions, it was found that the existence of Cd ²⁺, Cu ²⁺ and Ni ²⁺ had no impact on the adsorption of Pb²⁺.     

Molecular Characterization of Endophytic Bacteria from Metal Hyperaccumulator Aquatic Plant (Eichhornia crassipes) and Its Role in Heavy Metal Removal

In this study, among a collection of heavy metals resistant endophytic bacterial strains isolated from aquatic hyperaccumulator plant (Eichhornia crassipes), one plant growth promoting endophytic bacteria (PGPE), SVUB4 was selected for its ability to utilize 1-aminocyclopropane-1-carboxylic acid (ACC) as the sole N source and accumulate different heavy metals. The SVUB4 strain was characterized as Enterobacter sp. on the basis of its 16S rDNA sequences. Assessment of the parameters of plant growth promotion revealed the intrinsic ability of the strain for the production of IAA, siderophore and solubilization of insoluble phosphate. Furthermore, plasmid DNA analysis of Enterobacter sp. strain SVUB4 indicated the presence of a single large plasmid element. The results of plasmid curing experiments demonstrated that the ability of this strain to grow in presence of Cd and Zn was encoded by the 98 kb plasmid, whereas the ability to grow in the presence of Pb appeared to be encoded by the chromosome. The Cd and Zn removal capacity of the respective metal sensitive strain (plasmidless) were about 36 and 45 μg/g-1 DW, respectively, while the removal capacity of the both metal by metal resistant strain (p SVUB4) showed a significantly higher Cd and Zn removal capacity of 153 and 228 μg/g^?1 DW, respectively. However, both strains exhibited a similar pattern of Pb accumulation. The present observation also showed that for wild-type strain SVUB4 (pSVUB4), the overall level of IAA production in the absence and in the presence of Cd²⁺ or Zn²⁺was approximately the same. Nevertheless, strain SVUB4M in this respect appeared to be more sensitive to heavy metals: a noticeable decrease in IAA production was observed under the effect of both metals, especially with Cd²⁺.     

Uptake of lead,cadmium and zinc by the fairy shrimp,Branchinecta longiantenna (Crustacea: Anostraca)

Individuals of the fairy shrimp, Branchinecta longiantenna, were subjected to 5 concentrations (0.1 to 15 mg l^–1) of Pb in diluted habitat water at 13 °C. Lead concentrations (mg kg^–1 wet weight) in the animals were determined at 2-day intervals by digestion in nitric acid followed by atomic absorption analysis. The shrimp were also subjected to 0.1 mg l^–1 media of Cd and Zn, separately.Uptake rates by the fairy shrimp for the three metal ions at 0.1 mg l^–1 were: 0.111, 0.0885, and 0.0460 mg kg^–1 day^–1 for Zn, Pb, and Cd, respectively. After 2 days in 1.0 mg l^–1 Cd or Zn, the animals expired; but they surviced for 8 days in a 10 mg l^–1 Pb medium and for 2 days in 25 mg l^–1 Pb. Lead uptake demonstrated a linear dependence on the Pb concentration in the media.Shrimp survived at much higher tissue accumulations of Pb compared to Zn and Cd. Estimated lethal doses were 20, 1.2–2.4, and 0.4–1.4 mg kg^–1 wet weight for Pb, Zn, and Cd, respectively. Pb was found to be at much lower concentration than Cd or Zn in the natural pond water but between Cd and Zn levels in the sediment. Thus Cd and Zn probably present a greater threat to B. longiantenna than Pb, although Pb may be in higher concentration in the environment.Contribution 47, Laboratory of Ecology, The Claremont Colleges, Claremont, CA 91711, USA. Send reprint requests to Clyde Eriksen.     

Gm and Km(Inv) frequencies in two Roumanian populations

Summary Serum samples from 170 unrelated individuals from the Suceava District of Roumania and from 199 unrelated individuals from Bucharest, Roumania were tested for Gm(1, 2, 3, 5, 6, 13, 14, 17, 21) and Km(1)[Inv(1)]. Selected samples were also tested for Gm(15) and Gm(16).The frequencies of the three common Caucasoid haplotypes, Gm ^{3, 5, 13, 14}, Gm ^{1, 17, 21}, and Gm ^{1, 2, 17, 21} in these two populations were found to be similar to those in neighboring Slavic states and Hungary. Racial admixture was evidenced by the presence of the Gm ^{1, 13, 15, 16, 17} and Gm ^{1, 3, 5, 13, 14} haplotypes, which are primarily Mongoloid, and the Gm ^{1, 5, 13, 14, 17} haplotype which is primarily Negroid.Comparisons of these data with those from earlier studies of populations from Central Europe indicate that the frequency of the Gm ^{3, 5, 13, 14} haplotype within this region is high and essentially uniform. Published data for several blood group systems also indicate essentially uniform distributions of frequencies in this region. It is suggested that this region may be the center of a clin that radiates from it.Post-Doctoral Fellow supported by NIH Training Grant Gm07004.     

Effects of lead contamination on the clonal propagative ability of Phragmites australis (common reed) grown in wet and dry environments

Clonal propagation is important for the survival and maintenance of the common reed Phragmites australis. Pot culture experiments were conducted to investigate the effects of lead (Pb) concentration (0, 500, 1500, 3000, 4500 mg·kg^?1) and water stress on the clonal reproductive ability of this species. The Pb concentration found in plant organs, in decreasing order, was roots >shoots >rhizomes. There was a negative relationship between the growth of clonal propagative modules (excluding axillary shoot buds) and Pb concentrations, which caused a decrease in biomass, rhizome growth and number of axillary and apical rhizome buds. Daughter axillary shoots exhibited a tolerance strategy, with no significant change in their number; the axillary and apical rhizome buds, daughter apical rhizome shoots and rhizomes exhibited compensatory growth during the late stage of Pb (excluding 4500 mg·kg^?1) treatment in a wet environment. Pb applications above 500 mg·kg^?1 reduced these parameters significantly in the drought treatment, except for the number of axillary shoot buds, which did not change. Our results indicate that clonal propagative resistance to Pb contamination can occur via tolerance strategies, compensatory growth and a Pb allocation strategy, enabling these reeds to maintain population stability in wet environments. However, clonal modular growth and reproductive ability were inhibited significantly by the interaction between drought and Pb, which would cause a decline in P. australis populations in a dry environment. Lead concentrations of 4500 and 500 mg·kg^?1 in soils might meet or exceed the Pb tolerance threshold of clonally propagated reeds in wet and dry environments, respectively.