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Mining of minerals and precious elements leads to land degradation that need to be reclaimed using environmentally friendly and cost effective techniques. The present study investigated the potential effects of different organic amendments on cadmium (Cd) bioavailability in mining-degraded soil and its subsequent bioaccumulation in tomato and cucumber. The selected organic geosorbents (hard wood biochar (HWB), bagasse (BG), rice husk (RH), and maize comb waste (MCW)) were added at application rates of 3% and 5% to chromite mine-degraded soil containing Cd. Tomato and cucumber plants were then grown in the soil, and the roots, shoots, leaves, and fruits of each plant were analysed for Cd concentration, biomass production, and chlorophyll content. The results indicated that the different organic materials have variable effects on physiochemical characteristics of vegetables and Cd bioavailability. The biochar amendment significantly (P < 0.01) increased chlorophyll contents (20–40%) and biomass (40–63%), as did RH to a lesser extent (increase of 10–18% in chlorophyll content and 3–45% in biomass). Among the amendments, HWB was the most effective at reducing Cd bioavailability, wherein significant decreases were observed in Cd uptake by fruits of tomato (24–30%) and cucumber (36–54%). The higher application rate of 5% was found to be more effective for mitigation of Cd mobility and bioaccumulation in plants grown in mine degraded soil. The study results indicate that effective use of organic amendments, especially HWB, can significantly reduce Cd levels in vegetables, improve food quality, and reduce human-health risk while increasing biomass production. [ABSTRACT FROM AUTHOR]

Solar-driven photothermal conversion devices are proved to promising in fresh water generation, but often hindered due to complex manufacturing processes, low efficiency and poor reusability. Herein, we proposed a one-step carboxylated multi-walled carbon nanotube (MWCNTs-COOH) loading on the cotton fabric (CF), and assembled a jellyfish-shaped solar evaporator in which the evaporation layer acted as the body and cotton yarns (CYs) as the tentacles used for water transportation. The jellyfish-shaped solar evaporator has the advantages of separating the evaporation layer from bulk water, thereby effectively prevents heat dissipation and improves evaporation efficiency. The assembled evaporator exhibited an evaporation rate of 1.18 kg m−2 h−1 and a high energy conversion efficiency of 86.01% under 1.0 sun illumination (1.0 kW m−2). This simple preparation, high efficiency and excellent reusability jellyfish-shaped solar evaporator is expected to be used efficiently under natural light conditions, and has great application prospects for remote areas that lack fresh water supplies. Unlabelled Image • An efficient strategy is proposed to prepare MWCNTs-COOH/CF solar evaporator. • This evaporator possesses robust photothermal conversion ability. • The resultant composite is easy to scale production. [ABSTRACT FROM AUTHOR]