This paper provides an overview of different methods of assessing the trace metal (TM) contamination status of sediments affected by anthropogenic interference. The geochemical background determination methods are also described. A total of 25 papers covering rivers, lakes, and retention tanks sediments in areas subjected to anthropogenic pressure from the last three years (2019, 2020, and 2021) were analysed to support our examination of the assessment measures. Geochemical and ecotoxicological classifications are presented that may prove useful for sediment evaluation. Among the geochemical indices, several individual pollution indices (CF, Igeo, EF, Pi (SPI), PT_T), complex pollution indices (PLI, Cdeg, mCdeg, Pi_sum, PI_Avg, PI_aAvg, PIN, PI_Prod, PI_apProd, PI_vectorM, PI_Nemerow, IntPI, MPI), and geochemical classifications are compared. The ecotoxicological assessment includes an overview of Sediment Quality Guidelines (SQG) and classifications introduced nationally (as LAWA or modified LAWA). The ecotoxicological indices presented in this review cover individual (ERⁱ) and complex indices (CSI, SPI, RAC, PERI, MERMQ). Biomonitoring of contaminated sites based on plant bioindicators is extensively explored as an indirect method for evaluating pollution sites. The most commonly used indices in the reviewed papers were Igeo, EF, and CF. Many authors referred to ecotoxicological assessment via SQG. Moreover, PERI, which includes the toxic response index, was just as popular. The most recognised bioindicators include the Phragmites and Salix species. Phragmites can be considered for Fe, Cu, Cd, and Ni bioindication in sites, while Salix hybrid cultivars such as Klara may be considered for phytostabilisation and rhizofiltration due to higher Cu, Zn, and Ni accumulation in roots. Vetiveria zizanoides demonstrated resistance to As stress and feasibility for the remediation of As. Moreover, bioindicators offer a feasible tool for recovering valuable elements for the development of a circular economy (e.g., rare earth elements).

This study assesses the wood waste generation, its management practices, and its effects on the forests in Ghana. The rate of logging in Ghana has increased and this can be attributed to the increase in the establishment of Sawmilling companies in the country. Increased in the installation of sawmilling companies has increased the sawn timber production. The use of outmoded milling machines has led to an increase in waste generation. An increase in production has led to an increase in the annual allowable cut in the country, which has overrun the limit of sustainable forestry. A qualitative research method was employed for the research work. A well-structured questionnaire was administered to the study to solicit the views of the wood industries about wood waste generation and its management practices. The study population comprised of 50 sawmilling companies. From the data collected, it was observed that most of the timber production companies do not know how to manage the waste generated and the waste is left un-utilized. In general 80% of the timber production companies responded that they have an idea of wood waste management but do not have the technical know-how to manage the waste. It was observed that 80% of the timber production companies do not manage the waste they generate during their operations. Wood shavings, sawdust, wood slabs, offcuts, branches, and others are left un-utilized. From the observations made in the visited sawmills, chunks of waste are generated on the site. The fact that the wood which is un-utilized (waste) and the wood, which is utilized as sold products, are equal in cost to the company which highlights the poor material and cost-efficiency. Wood industry materials and cost efficiency, together with waste management practices and their contribution to deforestation in the country, are discussed.

The main objectives of this socio-technical study are to investigate the Indian farmers’ biomass production capacities and their perceptions and willingness to supply their surplus biomass to fuel an envisioned biomass-based power plant in three selected Indian states: Maharashtra, Madhya Pradesh and Tamil Nadu. For doing so, 471 farmers (about one-third from each state) have been interviewed in the field with info-sheet filled in by the field investigators. The farmers from all of the states appeared very much willing to sell their surplus biomass directly to a power plant. The farmers seem to depreciate the involvement of a middleman in the biomass procurement process. The farmers, however, appeared to highly appreciate a community-based association to regulate the biomass prices, with varying perceptions regarding government intervention. The majority of the farmers perceived the establishment of a biomass-based power plant in their region with positive economic outcomes. The farmers identified several barriers to supply biomass to a power plant where transportation logistics appeared to be the main barrier. The study recommends considering biomass collection, storage and transportation logistics as a fundamental segment of any envisioned investment in a biomass-based power plant. Biomass processing, such as pelletization or briquetting is recommended for efficient transportation of biomass at longer distances to reduce the transportation costs. The study further encourages the establishment of a farmers’ association aimed at collecting and selling biomass in agriculture areas predominant for small land holdings.

In many Baltic regions, short-rotation willow (Salix spp.) is used as a vegetation filter for wastewater treatment and recycling of valuable nutrients to upsurge bioeconomy development. In this context, a four-year field trial (2016–2019) was carried out near a wastewater treatment plant in eastern Finland (Outokumpu) to investigate the effect of the processed wastewater (WW) on biomass production as well as the nutrients uptake capability (mainly N and P) by a willow variety (Salix schwerinii). Results indicated that WW irrigation expressively increased the willow diameter growth and biomass yield around 256% and 6510%, respectively, compared to the control treatment site (without WW). The willow was also able to accumulate approximately 41–60% of the N and 32–50% of the P in two years (2018–2019). Overall, willow showed a total 20% mortality rate under WW irrigation throughout the growing periods (2017–2019) as compared to control (39%). The results demonstrate that willow has the potential to control eutrophication (reducing nutrients load) from the wastewater with the best survival rate and can provide high biomass production for bioenergy generations in cold climatic conditions.

In a greenhouse experiment, plant growth and copper (Cu) and zinc (Zn) uptake by four Salix cultivars grown in Cu and Zn contaminated soils collected from a mining area in Finland were tested to assess their suitability for phytoextraction. The cultivars displayed tolerance to heavily contaminated soils throughout the experiment. After uptake, total mean Cu concentrations in the leaves, shoots and roots in all cultivars and treatments ranged from 163 to 474 mg kg⁻¹ and mean Zn concentrations ranged from 776 to 1823 mg kg⁻¹. Lime and wood ash addition increased dry biomass growth (25–43%), chlorophyll fluorescence (Fv/Fm) values (3–6%), the translocation factor (TF) (15–60% for Cu; 10–25% for Zn), the bio-concentration factor (BCF) (40–85% for Cu; 70–120% for Zn), and metal uptake (55–70% for Cu; 50–65% for Zn) compared to unamended treatment across all cultivars. The results revealed that Salix cultivars have the potential to take up and accumulate significant amounts of Cu and Zn. Cultivar Klara (Salix viminalis × S. schwerinii × S. dasyclados) was found to be the most effective cultivar for phytoextraction since it displayed greater dry biomass production, Fv/Fm, TF, BCF values and uptake percentage rates of Cu and Zn compared to the other three cultivars. This study indicates that further research is needed to clarify the wider phytoextraction capabilities of different Salix cultivars.

This study was conducted to assess the survival rates, growth, and chlorophyll fluorescence (Fv/Fm) of four hybrid aspen (14, 191, 27, 291) and two European aspen (R3 and R4) clones cultivated in creosote- and diesel oil-contaminated soil treatments under three different plant densities: one plant per pot (low density), two plants per pot (medium density), and six plants per pot (high density) over a period of two years and three months. Evaluating the survival, growth, and Fv/Fm values of different plants is a prerequisite for phytoremediation to remediate polluted soils for ecological restoration and soil health. The results revealed that contaminated soils affected all plants’ survival rates and growth. However, plants grown in the creosote-contaminated soil displayed a 99% survival rate, whereas plants cultivated in the diesel-contaminated soil showed a 22–59% survival rate. Low plant density resulted in a higher survival rate and growth than in the other two density treatments. In contrast, the medium- and high-density treatments did not affect the plant survival rate and growth to a greater extent, particularly in contaminated soil treatments. The effects of clonal variation on the survival rate, growth, and Fv/Fm values were evident in all treatments. The results suggested that hybrid aspen clones 14 and 291, and European aspen clone R3 were suitable candidates for the phytoremediation experiment, as they demonstrated reasonable survival rates, growth, and Fv/Fm values across all treatments. A superior survival rate for clone 291, height and diameter growth, and stem dry biomass production for clone 14 were observed in all soil treatments. Overall, a reasonable survival rate (~75%) and Fv/Fm value (>0.75) for all plants in all treatments, indicating European aspen and hybrid aspen have considerable potential for phytoremediation experiments. As the experiment was set up for a limited period, this study deserves further research to verify the growth potential of different hybrid aspen and European aspen clones in different soil and density treatment for the effective phytoremediation process to remediate the contaminated soil.