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Military activities can contaminate productive land with potentially toxic substances. The most common trace metal contaminant on military bases is lead (Pb). A field experiment was begun in 2016 at Fort Riley, KS, in an area with total soil Pb concentrations ranging from 900 to 1,500 mg kg-1 and near-neutral pH. The main objectives were to test the potential of Miscanthus sp. for phytostabilization of the site and to evaluate the effects of soil amendments on Miscanthus growth, soil-plant Pb transfer, bioaccessibility of soil Pb, and soil health. The experimental design was a randomized complete block, with five treatments and four replications. Treatments were (a) existing vegetation; (b) Miscanthus planted in untilled soil, no amendments; (c) Miscanthus planted in tilled soil; (d) Miscanthus planted in tilled soil amended with inorganic P (triple superphosphate applied at 5:3 Pb:P); and (e) Miscanthus planted in tilled soil amended with organic P (Class B biosolids applied at 45 Mg ha-1 ). Tilling and soil amendments increased dry matter yields only in the establishment year. Total Pb uptake, plant tissue Pb concentration, and soil Pb bioaccessibility were significantly less in the Miscanthus plots amended with biosolids than the Miscanthus plots with no added P across all 3 yr. Enzyme activities, organic carbon, and microbial biomass were also greater in biosolids-treated plots. Results show that planting-time addition of soil amendments to Pb-contaminated soil supported Miscanthus establishment, stabilized and reduced bioaccessibility of soil Pb, reduced concentration and uptake of Pb by Miscanthus, and enhanced soil health parameters.

The commercial production of M. × giganteus for bioenergy and lignocellulose products requests research on plant-parasitic nematodes which can cause serious crop yield losses when the crop is cultivated long-term in big plantations at the different environmental conditions and geographical locations. The occurrence of M. × giganteus plant-feeding nematodes and temporal-spatial aspects of distribution were studied in 2016–2017 at the crop established stands of 1–10 years of age representing, consequently, 8 locations and 6 soil types in Ukraine and 9 localities and 8 soil types in Poland. Fifty-three plant-feeding nematodes of belonging to 22 genera and 10 families were identified, including plant-parasitic species which populations in several locations exceeded the estimated damage threshold. The distribution of nematode species was evaluated by applying the non-metric multidimensional scaling approach indicated spatial heterogeneity of sampling points and community dynamics. The relationships among the hyphal and root hair feeders, semiendoparasites and ectoparasites were characterized, and these groups were proposed as indicators for assessing the state of M. × giganteus plantations with different years of cultivation. Obtained results can be applied for improvement of M. × giganteus production technologies to prevent the risk of biomass yield reduction posing by plant-parasitic nematodes in temporal regions of East-Central Europe. Further study is needed to develop nematode-based biological monitoring of perennial grassland to enhance the sustainability of bioenergy systems.

The second generation energy crop Miscanthus x giganteus (Mxg) was cultivated in pots with mixtures of clean and petroleum industry contaminated soil affected by petroleum, Pb, Zn contamination and high salinity. The survival rate reached 100%, nevertheless the biomass parameters were negatively affected even in the lowest proportion of contaminated soil. In the lowest contamination, where the plant grew still quite successfully, C10-C40 degradation was significantly enhanced compared to the unplanted control with degradation of 58 ± 14%. The plant contribution to aliphatics degradation was significantly correlated with biomass, thus it was negligible in higher contamination. A similar pattern was documented in development of the soil bacterial community. The shift in community structure after Mxg cultivation was observed mainly in the soil with the lowest contaminant proportion, though an increase of bacterial diversity in the miscanthus rhizosphere was observed in all cases. Relative abundance of Actinobacteria was reduced on behalf of several less abundant phyla (Verrucomicrobia, Bacterioides, Acidobacteria). The majority of genera identified as potential petroleum degraders (Pseudomonas, Shinella, Altererythrobacter, Azospirillum, Mesorhizobium, Dyella) were more abundant in contaminated soil with miscanthus, suggesting that Mxg could be a promising crop for phytomanagement of petroleum contaminated soils but salt phytotoxicity needs to be mitigated first.

Second-generation biofuel crop miscanthus is one of the most promising plants tested for phytomanagement of contaminated sites. In this preliminary pot case study, the most used hybrid Miscanthus x giganteus was cultivated in three different real contaminated soils: agricultural soil contaminated with Cd, post-military soil slightly contaminated with Zn, Pb and Cd, and soil contaminated by petroleum industry with metals and hydrocarbons. The stress response of plants and soil microbial communities was monitored to receive data that are important for successful phytomanagement application. With metals only, the plant grew well, and chlorophyll fluorescence measurement proved their good vitality. Changes in leaf anatomy (leaf thickness and sclerenchyma cells area) were additionally determined in post-military soil compared to agricultural. On the contrary, in petroleum-contaminated soil, the biomass yield was too reduced and also physiological parameters were significantly decreased. The response of microbial communities also differed. In agricultural soil, no microbial stress was determined. In post-military soil, it became reduced during the experiment, and in petroleum contamination, it increased year-on-year. It could be concluded that miscanthus is suitable for cultivation in metals contaminated soils with potential for microbial communities support, but in soil contaminated by the petroleum industry, its application did not seem meaningful.

Applying phytotechnologies with energy crops on lands contaminated with trace elements provides cellulosic biomass and improves soil health. The process can be reflected in changes in the soil nematode community structure. This study assessed the nematode community composition of soil with Miscanthus grown with different agronomic practices. The research was conducted at Fort Riley, Kansas, USA, in soil with aged contamination by Pb at 1000 to 1500 mg/kg. The experimental design was a randomized complete block composed of four replications of five treatments: Control-undisturbed mixed plant cover and four conditions of Miscanthus growth, which consisted of No-till, Till (immediately before planting), Till + P, and Till + biosolids. Analysis of abundance, diversity, and community functional status indicators showed differential sensitivity of nematode taxa to agronomic treatments. Significant transformations in the nematode trophic group structure occurred under Miscanthus cultivation compared with the undisturbed mixed plant cover. Shannon and Pielou index response to agronomic treatments illustrated decreasing nematode community diversity with all Miscanthus agronomic conditions. However, agronomic practices led to increasing nematode community maturity, but those effects varied between spring and fall seasons. Increasing herbivores and omnivore-predators were the primary drivers of the observed changes in the nematode community due to planting Miscanthus. The nematode ecological structure indicators suggested that growth in Pb-contaminated land using different agronomical practices likely affects essential soil processes. More study is needed to define the effects of pre-plant tillage and amendments to soil nematode communities and Miscanthus yield over multiple growing seasons of this perennial crop.

Miscanthus × giganteus (M. × giganteus) is a perspective plant produced on marginal and contaminated lands with biomass used for energy or bioproducts. In the current study, M. × giganteus development was tested in the diesel-contaminated soils (ranged from 250 mg kg−1 to 5000 mg kg−1) and the growth dynamic, leaves quantity, plants total area, number of harvested stems and leaves, SPAD and NPQt parameters were evaluated. Results showed a remarkable M. × giganteus growth in a selected interval of diesel-contaminated soil with sufficient harvested biomass. The amendment of soil by biochar 1 (produced from wastewater sludge) and biochar 2 (produced from a mixture of wood waste and biohumus) improved the crop’s morphological and physiological parameters. Biochar 1 stimulated the increase of the stems’ biomass, while biochar 2 increased the leaves biomass. The plants growing in the uncontaminated soil decreased the content of NO3, pH (KCl), P2O5 and increased the content of NH4. Photosynthesis parameters showed that incorporating biochar 1 and biochar 2 to the diesel-contaminated soil prolonged the plants’ vegetation, which was more potent for biochar 1. M. × giganteus utilization united with biochar amendment can be recommended to remediate diesel-contaminated land in concentration range 250–5000 mg kg−1.

The semi-field research on using second-generation biofuel crop Miscanthus x giganteus for restoration of former military site in Kamenetz-Podilsky, Ukraine was carried out during two vegetation seasons. Despite high metal pollution of soil, in particular, by Fe, Mn, Ti, and Zr, no growth inhibition was observed. The concentrations followed pattern soil > roots > stems > leaves. Accumulation of particular metals in roots was different: Fe, Mn and Ti were accumulated rather palpably after the first vegetation season and less tangible after the second one. Cu, Pb and Zn were less accumulative in both vegetation seasons, and for As and Pb the accumulative concentrations were very small. Accumulations in the aboveground parts of the plant in comparison to roots were significantly lower in case of Fe, Ti, Mn, Cu, Zn, Sr and even statistically comparable to zero in case of As, Pb and Zr. Calculated translocation ratio of metals in the plant’s parts preferably indicated lack of metals’ hyper accumulation. Generally, no correlations were observed between concentrations of metals in the soil and in the upper plant’s parts. The research confirmed the ability of Miscanthus x giganteus to grow on the military soils predominantly contaminated by metals.

The second-generation energy crop Miscanthus x giganteus (M. xgiganteus) is a perspective plant for phytoremediation of contaminated lands and the production of biomass. The excellent quality biomass can be ensured by adding soil amendments or inoculation of the plant by plant growth-promoting bacteria (PGPB). The main goal of the current study was to research the influence of PGPB Bacillus altitudinis strain KP-14 isolated from the post-mining aged contaminated soil in Vsebořice dump, Usti nad Labem to the phytoremediation parameters and biomass production of M. xgiganteus. The experiment was done in the greenhouse conditions using the initial aged soil contaminated by the following trace elements (TEs): V, Cr, Mn, Ni, Cu, Zn, Sr, Pb and the same aged soil, additionally artificially contaminated by Pb. The results showed that PGPB treatment increased the growth process and leaves, stems, and roots biomass at harvest by 49%, 86%, and 76%, respectively. In the presence of B. altitudinis strain KP-14, the translocation factor decreased, the uptake index of TEs remained low and the process can be classified as phytostabilization. The finding showed that the application of PGPB strain could be used in the sustainable production of M. xgiganteus at the TEs contaminated soil.

There are many locations where soil quality improvements would be beneficial because of contamination, erosion, flooding, or past human activities. Miscanthus, a C-4 grass related to sugarcane, grows well in mildly contaminated soil and on sites where soil quality is poor, particularly with respect to nitrogen. Because of its high biomass yield, it is of interest as an energy crop, and as a plant to use for simultaneous crop production and phytoremediation. Here we review recent literature on using miscanthus for combined biomass production and phytoremediation of contaminated and marginal lands. We analyze both advantages and disadvantages for production of this crop along with phytoremediation of sites contaminated with metals and petroleum hydrocarbon. Reports of laboratory and field investigations, which use Miscanthus spp. for stabilizing and removing metals are considered. The potential for growing miscanthus commercially at contaminated and marginal sites in the regions of Central and Eastern Europ...

Miscanthus grows well in some marginal and contaminated soils, and it has the potential to be used as a biofuel. Copper and cobalt are heavy metals that sometimes are present as contaminants in soils at concentrations that may impact the safety of products that are harvested. Laboratory research has been conducted with Miscanthus sacchariflorus M. to investigate metal uptake of copper and cobalt because metal concentrations in the harvested parts of miscanthus are important for biofuel applications. The results show that the use of miscanthus for biofuel from soil contaminated by heavy metals depends mainly on the nature of contaminated metals: cobalt was detected only for highest treated concentration of metal and mainly in the roots. The highest concentration of copper was detected in the roots however this metal was detected in stems and leaves of miscanthus as well. Miscanthus biomass harvested from cobalt contaminated soil may be used for energy production because the harvested part accumulated only limited traces of the metal. The experimental results are in reasonable agreement with other results from the literature.

The soil-to-root transfer and translocation coefficients of essential and non-essential elements in different parts of Vitis vinifera L. depend on environmental and anthropogenic factors and can be variety-specific. Knowledge about uptake and translocation of trace elements by different varieties is necessary for prediction contamination of grapes and wine products and understanding tolerance of cultivars to the environment. The study focused on determination of transfer and translocation patterns of so-called essential (Mn, Fe, Cu and Zn) and non-essential (Cd, Co, Cr, Ni and Pb) elements by vines of Chardonnay and Muscat white of the same age and grown at the similar environmental conditions in Inkerman vineyard, South Crimea in 2013. Samples of irrigation water, soil, fine and coarse roots, leaves and canes were taken in May and berries were harvested in August. The soil enrichment factor, soil-to-root transfer and translocation (roots, leaves and canes) coefficients were calculated based on the trace elements concentration gradients. The principle component analysis and the variables correlation were used for the data treatment. Results showed the contamination of vineyard soil by Pb, which was due to contaminated irrigation water. There was a little variation between Chardonnay and Muscat white in terms of essential trace elements transfer from soil to roots. Translocation patterns were significantly different for non-essential elements, cultivars and plant parts. Pb had the highest variability in transfer and translocation patterns between varieties. Bio-concentration factors varied between cultivars and the highest value was detected for Zn and Fe.