The contamination of soil with heavy metals is a severe problem due to adverse impact of heavy metals on environmental safety and human health. It is essential to remediate soil contaminated with heavy metals. This study has evaluated the effects of pine biochar, kaolin, and triple super phosphate (TSP) on multiple heavy metals (Ni, Zn, Cu, and Cd) in contaminated soil and accumulation of heavy metals in plants. The amendments can reduce availability of heavy metals in soil by increasing pH, adsorption, complexation, or co-precipitation. Different amendments have variable effects on accumulation of heavy metals in plants and in soil due to its diverse mechanism of stability. The results showed that application of triple super phosphate (TSP) has significant reduced soil Cd exchangeable (EXC) fraction from 58.59 to 21.30%. Bound to carbonates (CAR) fraction decreased from 9.84 to 5.11%, and bound to Fe-Mn oxides (OX) fraction increased from 29.61 to 69.86%. The triple super phosphate (TSP) has the ability to stabilize Cu and especially Cd. However, triple super phosphate (TSP) has enhanced ecological risk of Zn and Ni. Application of pine biochar has significantly enhanced soil pH. The kaolin has significantly reduced EXC fraction of Cd and increased OX fraction of Cu. The amendments and heavy metals have not caused significant effect on SPAD value of Buxus microphylla Siebold & Zucc (B. microphylla). The triple super phosphate (TSP) has significant decreased biomass of B. microphylla and bamboo-williow (Salix sp.) by 24.91 and 57.43%, respectively. Pine biochar and kaolin have increased the accumulation of Zn and Cd in plants. It is concluded that triple super phosphate (TSP) was effective in remediation of Cd and kaolin was effective in remediation of Cd and Cu. Pine biochar was effective in remediation of Cd, Cu, and Zn.

Background The sudden outbreak of COVID-19 had a great impact on the physical and mental health of people all over the world, especially for students whose physical and mental development was not yet mature. In order to understand the physical and mental conditions of students during the epidemic period and provide a theoretical basis for coping with psychological problems in public health emergencies, this study explored the mediating role of sleep disorders in the effect of the psychological stress response (PSR) on non-suicidal self-injury (NSSI), along with the moderating role of emotional management ability (EMA). Methods The SRQ-20, Pittsburgh Sleep Quality Index, NSSI Behavior Questionnaire, and Emotional Management Questionnaire were used to investigate the mental health of Chinese students in April 10–20 (Time point 1, T1) and May 20–30 (Time point 2, T2), 2020. A total of 1,955 students (Mage = 19.64 years, 51.4% male) were examined at T1 and 342 students (Mage = 20.06 years, 48.2% male) were reassessed at T2. Results Overall, the detection rate of PSR and NSSI were 17.60% (n = 344) and 24.90% (n = 486) respectively in the T1 sample, and were 16.37% (n = 56) and 25.44% (n = 87), in the T2 sample. We also found that sleep disorders played a mediating role in the effect of PSR on NSSI in the T1 and T2 samples. In addition, EMA was shown to regulate the effect of PSR on sleep disorders and the effect of sleep disorders on NSSI in the T1 samples. Conclusion We found that PSR resulting from public health emergency might lead to NSSI behaviors in individuals. PSR may also cause sleep disorders, which can bring about NSSI. However, these effects were also moderated by the EMA. This research expands our understanding of PSR and NSSI in students during the pandemic.

Hypoxia affects plant growth, hormone content, various enzyme activities, cell structure, peroxide production, and metabolic level, therefore reducing crop yield. This study assessed the physiological, biochemical, and metabolic characteristics of Phyllostachys praecox. Results revealed that hypoxia stress treatment significantly inhibited plant growth. Leaf chlorophyll contents was initially improved and then reduced with plant growth time. Under hypoxia stress, the root activity significantly was reduced, leading to the decrease in the nutrient absorption and transport. Yet, with low oxygen concentration, the contents of ethanol, acetaldehyde, and lactic acid were improved. With hypoxia stress, phospholipids and amino acids were the main metabolites of Phyllostachys praecox. Glycosphospholipid metabolism is the key pathway in responding to hypoxia stress significantly (p < 0.05), and lysophosphatidlycholine (lysoPC) and phosphatidylcholines (PC) in the metabolites of this metabolic pathway were significantly enhanced. Our study reveals the mechanism of Phyllostachys praecox cell membrane responding to hypoxia stress based on molecular level. This is conducive to finding targeted solutions to improve the productivity of Phyllostachys praecox to better optimize a mulching approach in the bamboo forest.

Background Biochar is an important material for remediation of Cd in contaminated paddy soils. However, different biochars have variable effects on bioavailability of Cd while single biochar cannot properly amend immobilized Cd. Co-production of biochar from peanut shells and maize straw at different mass mixing ratios (1:0, 1:1, 1:2, 1:3). The characteristics, properties and effects of co-pyrolysis biochars on amendments of Cd polluted paddy soil was evaluated. Results Our research revealed that yield, ash, elemental contents and specific surface area of co-pyrolysis biochars have variable amendment effects compared with single biochar. The co-pyrolysis biochars have produced rich oxygen-containing functional groups and crystal structure, especially 1P3M (co-pyrolysis biochar produced from peanut shell and maize straw in mass ratios of 1:3). The addition of biochar has significantly enhanced pH and EC value, however, content of available Cd during incubation was significantly reduced compared with control treatment. The efficiency of biochars have reduced available Cd in order of 1P3M > M > 1P1M > 1P2M > 2P1M > 3P1M > P after incubation. The 1P3M was most effective in reducing CaCl2-extractable Cd concentration up to 43.97%. The BCR sequential extraction method has produced lowest exchangeable fraction Cd content and highest residual fraction Cd content in 1P3M among all biochar amended treatments. Conclusions It is concluded that 1P3M has a much greater potential to decreased the bioavailability of Cd in contaminated paddy soil. And 1P3M was highly effective for transporting Cd from soluble form to less toxic stable forms in polluted paddy soils. Graphical Abstract

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