1,720,964 research outputs found
Evaluation of phytostabilization of mine tailings after biochar amendment.
No full textPhytostabilization is one of the possible interventions to reduce the risks of contamination posed by mine tailings. This technique aims at reducing the mobility of the pollutants by establishing a green cover on the wastes. Recent studies, have focused the attention on biochar application to soil. Biochar is a C-rich product obtained when biomass is heated with limited oxygen supply and at relatively low temperature (<700°C). Some experiments revealed the potential benefits that biochar application induces to the soil in terms of property changes that turns into yield improvements. Biochar also seems to reducing the uptake of toxic elements by plants by reducing their bioavailability. The case study is represented by the past mining site of Cave del Predil (NE Italy) where about 20 hectares of dumping site lay undisturbed. Among the local species found on the site, Poa alpina and Anthyllis vulneraria were selected as possible candidates for phytostabilization. Two other species were selected: Festuca rubra and Buphtalmum salicifolium. The pot experiment aims at testing the four species on the following substrates: control (untreated mine tailings); 3 levels of equal rate of biochar and compost amendments applied to the mine tailings (0.5, 1 and 2%dw); the previous 4 substrates with mineral fertilization (NPK). At the end of the growing period, the plants will be harvested and the heavy metals content will be analyzed in their tissues (roots and shoots). The data from the metal uptake and accumulation and the biomass production will give important hints on the feasibility of the remediation process
Hyperaccumulation of thallium is population-specific and uncorrelated with caesium accumulation in the thallium hyperaccumulator, Biscutella laevigata
No full textAims Thallium hyperaccumulation has previously
been observed in the field but there are no laboratory
confirmations for Biscutella laevigata. Tolerance and
accumulation of thallium and its chemical analogue
caesium were compared in one non-metallicolous and
three metallicolous (calamine) populations of the candidate
Tl hyperaccumulator species, B. laevigata.
Methods Tolerance and accumulation were evaluated
in hydroponics. Moreover, Tl and Cs accumulation
were measured at different K concentrations in the
nutrient solution. Seedlings were also grown in Tl
contaminated calamine soil.
Results Estimated from their root growth response, all
the calamine populations showed hypertolerance to Tl,
although to very different degrees. Foliar Tl hyperaccumulation
from hydroponics and soil was apparent
in two populations. In one of them, it was a highaffinity
phenomenon, but it was only apparent at high
Tl exposure levels, and not associated with enhanced
root-to-shoot translocation in the other one. There was
no considerable inter-population variation in Cs tolerance
and accumulation, except that one population
showed a relatively low Cs retention in its roots under
low exposure.
Conclusions Tl hyperaccumulation and hypertolerance
are population-specific traits in B. laevigata. Cs
accumulation and tolerance are less variable and largely
uncorrelated with Tl accumulation and tolerance
Linking phytotechnologies to bioeconomy; varietal screening of high biomass and energy crops for phytoremediation of Cr and Cu contaminated soils
Full text linkEnerbiochem was a project devoted to study new strategies of industrial valorisation of high biomass crops grown on brownfields
or contaminated soils not suitable for food production.
Chromium and copper accumulation and toxicity were examined in different species of agronomic interest. Cultivars of Brassica
carinata A. Braun (7), Brassica juncea (L.) Czern. (4), Brassica napus L. (4), Raphanus sativus L. (4), inbred lines of Helianthus
annuus L. (6) and cultivars of Nicotiana tabacum L. (3) were screened for the best genetic materials to be used with the aims: i)
to produce the highest biomass in contaminated soils; and ii) possibly to phytoremediate them. Cr and Cu accumulation in shoots
were evaluated on 16 days old plants grown for additional 5 days in the presence of either Cr (60 μM) or Cu (2 μM) in hydroponic.
They were characterised for Cr and Cu concentrations in roots and shoots, shoot biomass, and total chlorophyll as well.
Shoot biomass was significantly lower in Brassica species than in R. sativus, H. annuus and N. tabacum under Cr treatments.
On the contrary, under Cu treatments, N. tabacum produced the lowest biomass in respect to other species. Potentially toxic element
concentrations varied among genetic material and some genetic material resulted less affected (higher chlorophyll content
and shoot biomass) even under higher Cu or Cr concentrations in shoot. Potential candidates within each species, to be used for coupling
phytoremediation and biomass production on slightly Cr-Cu potentially contaminated soils are listed
Metallophytes and thallium hyperaccumulation at the former Raibl lead/zinc mining site (Julian Alps, Italy)
No full textAn ecological survey of metallophytes belonging to the Thlaspietum cepaeifolii plant community was carried out at the former
Raibl lead and zinc mining site (Julian Alps, Italy). The aims of this work were to evaluate metal hyperaccumulation and to
determine whether it was restricted to a single element or, instead, involved multiple elements. The concentrations of Cd,
Pb, Tl and Zn were measured in specimens of Alyssum wulfenianum, Biscutella laevigata subsp. laevigata, Minuartia verna and
Thlaspi rotundifolium subsp. cepaeifolium collected from native and mining soils, mine tailings and stream banks. Cadmium
hyperaccumulation was not demonstrated, whereas in the case of Pb and Zn contradictory results were obtained. Thallium
hyperaccumulation was strongly confirmed in B. laevigata subsp. laevigata (up to 32,661 mg kg71 of Tl in shoots and
bioconcentration factor41). Surprisingly, this was also discovered in A. wulfenianum and M. verna (up to 1934 and
3632 mg kg71 of Tl in shoots, respectively, and bioconcentration factor41). Multiple metal hyperaccumulation was
verified in B. laevigata subsp. laevigata (Pb and Tl), M. verna and T. rotundifolium subsp. cepaeifolium (Pb, Tl, and Zn)
although it could not be confirmed in any of these species when coefficients calculated on shoot concentration of the
elements were considered
A decade of research on phytoremediation in North-East Italy: lessons learned and future directions
No full textTolerance and accumulation of thallium in three geographically distant populations of Biscutella laevigata L. subsp. laevigata Mant.
No full textPlantlets of two metallicolous and one nonmetallicolous populations of Biscutella laevigata subsp. laevigata were grown hydroponically for eight days at increasing concentrations of Tl: control, 1, 10 or 100 ppm Tl. Population tolerance to excess Tl was evaluated using a root elongation test. Tl concentration in shoots and roots was used as additional evaluation criteria. Based on the indicators used we confirmed the tolerance of population from Les Malines (F) (Lem) and demonstrate the tolerance of population from Cave del Predil (I) (Cap) and its capacity to accumulate Tl in shoots and roots (up to 28,745 mg kg-1 in shoots). Moreover the genetic structure was investigated using Amplified Fragment Length Polymorphism (AFLP) markers. All the results indicate that Cap population property of tolerance and accumulation of Tl is not a mere environmental effect but has also genotype bases and it is probably a constitutive and adaptive trait
Copper accumulation in five weed species commonly found in the understory vegetation of Mediterranean vineyards
No full textCopper (Cu) concentration in agricultural soils often exceeds toxicological limits due to application of Cu-based fungicides. The potential of weeds for their use as functional cover plants in vineyard management and phytoremediation practices is little explored. We identified five weed species widely present in vineyards and assessed their Cu accumulation from eleven Mediterranean vineyards (soil Cu: 60–327 μg g−1) and two adjacent control sites (soil Cu: 15–30 μg g−1). Soils and plants were characterized by their physico-chemical properties and nutrient content. We applied multivariate techniques to analyze relationships between soil properties and leaf nutrient composition. Copper tolerance and accumulation traits were further tested in hydroponics using a series of CuSO4 concentrations (0.1–16 μM). Under field conditions, the highest Cu concentration in both roots and leaves were found in Lolium perenne (221 and 461 μg g−1, respectively), followed by Plantago lanceolata, Rumex obtusifolius and Taraxacum officinale (>100 μg g−1 Cu in leaves). Only one species, Trifolium repens, did not accumulate remarkable Cu concentrations. Overall, and as revealed by the multivariate analyses, leaf Cu concentration was driven by soil Cu content, soil texture, organic matter, nitrogen, and Cu uptake into roots. However, functional regression analysis and controlled experiments suggested that Cu might be additionally absorbed from the deposits on the leaf surface related to the Cu-fungicide treatments and soil dust. Our study highlights the importance of intra-specific variability in Cu accumulation among weed species in Cu-contaminated agricultural soils. Further validation of these findings under controlled conditions could provide essential insights for optimizing management and remediation strategies
Dianthus sylvestris subsp. sylvestris as a promising candidate for phytostabilization of copper-contaminated post-mining sites in Alpine ecosystems
No full textThe lack of remediation of inactive mine sites is a serious global concern, as they pose risks to the environment, human health, and safety. The potential of Dianthus sylvestris subsp. sylvestris to remediate post-mining sites contaminated with copper (Cu) at high altitudes, which is a challenging task for most management strategies, was explored in this study. More than 1300 mg Cu kg−1 in shoots were found in plants collected at the Monte Avanza legacy mine site (Alps). However, it is unclear whether this is due to hyperaccumulation or foliar contamination. To address this gap, field samples were washed with two different protocols, and a controlled Cu-tolerance test was conducted. While very high Cu concentrations, exceeding the Cu hyperaccumulation threshold of 300 mg kg−1, were found in samples washed with water, results for the plants cleaned with a more rigorous approach with EDTA suggested Cu exclusion strategy. Under controlled conditions, the plant showed Cu hypertolerance but did not hyperaccumulate Cu. Thus D. sylvestris presents a Cu exclusion strategy rather than hyperaccumulation potential, making it a suitable candidate for Cu phytostabilization at high altitude legacy mine sites. The study emphasizes the need for experiments under controlled conditions when assessing the phytoremediation potential
- …
