Accumulation and distribution of zinc within Miscanthus × giganteus plants grown on elevated Zn concentrations and their photosynthetic performance were investigated. High concentrations of Zn in soils caused an increase of its concentrations in all plant organs. The bioconcentration factor, bioaccumulation factor, and translocation factor were lower than one indicating that M. × giganteus is an excluder plant species. Excessive Zn induced visible leaf damage, i.e. chlorosis and necrosis, only in the oldest leaves, pointing to Zn accumulation. Elevated amounts of Zn in leaves significantly lowered the photosynthetic rate, transpiration rate, stomatal conductance, intercellular CO₂ concentrations, parameters of chlorophyll a fluorescence, and chlorophyll b content. Despite Zn excess in leaves, there was no severe reduction in the maximal quantum yield of PSII photochemistry, indicating a high photosynthetic capacity, high tolerance to elevated Zn concetrations, and ability of M. × giganteus to grow on Zn-contaminated soils.

Heavy metal contamination of aquatic ecosystems directly threatens the health, production and biodiversity of aquatic and surrounding terrestrial ecosystems, and it represents a serious global problem. Metal extraction during ore processing produces large amounts of wastes that remain in tailings at the mining site. Fine waste particles represent a long-term source of potentially toxic metals that can be released into the ground and surface water as a result of their progressive chemical weathering. Aquatic macrophythes have a major role in absorption and accumulation of heavy metals and thereby in natural water purification. The presence of naturally growing plants on mine tailing ponds indicates their tolerance of heavy metal pollution and suggests a possible role for them in phytoremediation. In the present study, we analysed the concentrations of heavy metals (Fe, Mn, Ni, Zn, Pb, Cd, Co, Cu) in Phragmites australis plants growing spontaneously in shallow water of several mine tailing ponds. The aims of the study were to define chemical properties of the mine spoils, determine the concentrations of heavy metals in different plant organs and assess the phytoremediation potential of common reed. The investigated sediments were notably rich in both total and available forms of Fe, Pb, Zn and Cu, with their upper concentrations close to phytotoxic levels. The greatest amounts of almost all of the investigated metals in plants from all three mine tailing ponds were found in the roots, with their concentrations positively correlated with the amounts of their available forms in the corresponding sediment. The far higher metal concentrations in the roots in comparison with other plant organs clearly indicate that the metals were strongly sequestrated within root cortical tissues and were not transferred across the endodermis. Taken altogether, the presence of the greatest amounts of metals in roots, high bioaccumulation factor and low translocation factor show that P. australis is an excluder plant species with a good phytostabilisation potential. As such, it might be efficiently used in rhizofiltration of wastewaters.

This paper investigates the environmental impacts and energy benefits of the cultivation of Miscanthus (Miscanthus × giganteus Greef et Deu.), in order to initiate its use in sustainable household heating in the Republic of Serbia. Based on the analysis of available data regarding the use of agricultural machinery in Serbia, a Miscanthus supply chain is constructed and examined in detail, scrutinizing all relevant operations—from planting of rhizomes to thermal energy production. Results of the life cycle assessment identify the briquetting process as the most environmentally burdensome operation due to high electricity consumption and low productivity. It is concluded that an average yield of 23.5 t dry matter (d.m.) year⁻¹ obtained from 1 ha of chernozem soil would have energy output:energy input (EO:EI) ratio of 51:1, and would release 365.5 gigajoules (GJ) of heat during combustion in a boiler. With this amount of energy, around 383 m² of a free-standing family house in Serbia can be heated annually. The same amount of energy is obtained by the combustion of 22 t of lignite or 23 t of wood logs. The substitution of lignite and wood with Miscanthus briquettes would lead to significant reduction of CO₂ equivalents (eq), SO₂ eq, P eq, N eq, 1,4 dichlorobenzene (1,4-DB) eq, Non-methane volatile organic compound (NMVOC), PM10 eq and U235 eq emissions. This designates Miscanthus as a more sustainable energy solution for household heating. In instances where more modern agricultural machinery is used, emission reduction is higher, except for CO₂ eq due to higher emission factors predicted for more powerful engines. Depending on Miscanthus’ annual yield, the replacement of set-aside land with Miscanthus plantations result in carbon (C) sequestration from 0.08 t C ha⁻¹ year⁻¹ to 0.91 t C ha⁻¹ year⁻¹. In a modern machinery scenario, C sequestration is only attainable when maximal Miscanthus yield is obtained. The combined use of machinery with different engine power is the best option for Miscanthus cultivation in Serbia.