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33% organic carbon of the hydrochar was released. The aromaticity of DSAs decreased with increasing Tp and tr. The molecular weights of the DSAs and DPMs decreased with increasing Tp and tr. This study uncovered hydrochar’s molecular structure as well as the content and properties of its labile fractions. Results can be used to help design specific hydrochars for potential applications, based on the trend of the molecular change under the condition of the studied parameters optimization to produce hydrochar in this study.The Amazon basin contains more than 20% of the world’s freshwater fishes, many of ecological and economical importance. An increase in temperature of 2.2 to 7 °C is predicted to occur within the next century in the worst-case scenario of climate change predictions, which will likely be associated with an increase in the prevalence and duration of reduced water oxygen levels (hypoxia). Furthermore, there is an increasing frequency of heat waves in the Amazon basin, which exacerbates issues related to temperature and hypoxia. Increases in temperature and hypoxia both constrain an organism’s ability to supply oxygen to metabolizing tissues, thus the ability to cope with thermal and hypoxic stress may be correlated. Here, we reveal a positive correlation between acute thermal tolerance and acute hypoxia tolerance amongst 37 Amazonian fish species at the current river temperatures of 28-31 °C. The effects of long-term (10 days or 4 weeks) increases in temperature were investigated in a subset of 13 species and demonstrated that 2 species failed to acclimate and survive at 33 °C, 9 species failed at 35 °C, and only 2 species survived up to 35 °C. Of those that survived long-term exposure to 33 or 35 °C, the majority of the species demonstrated only an improvement in acute thermal tolerance. In contrast, hypoxia tolerance was reduced following acute- and long-term exposure to 33, 35 or 37 °C in all species investigated. The results of this study suggest that many of the fish species that inhabit the Amazon may be at risk during both short- and long-term temperature increases and these risks are exacerbated by the associated environmental hypoxia.S-metolachlor (S-ME) is a widely used chiral herbicide that can cause potential ecological risks via long-term usage. In this work, we chose a model plant, wheat, as the test material to determine the effects of applying 10 mg/kg S-ME to soil on its fresh weight, chlorophyll and malondialdehyde (MDA) content, and superoxide dismutase (SOD) activity and the diversity and structural composition of the phyllosphere microorganisms after 7 and 14 days of exposure. Our work showed that this concentration of residual S-ME in soil only slightly decreased plant biomass and had little effect on lipid peroxidation, the antioxidant enzyme system and chlorophyll content. Interestingly, although the test concentration of S-ME did not exert strong inhibitory effects on the physiological activities of wheat, it decreased the diversity of phyllosphere microbial communities and changed their structure, indicating that microorganisms were more sensitive stress indicators. S-ME reduced the colonization by some beneficial bacteria related to plant nitrogen fixation among the phyllosphere microorganisms, which influenced the growth and yield of wheat because these bacteria contribute to plant fitness. In addition, S-ME affected the association between the host and the composition of the phyllosphere microbial communities under different growth conditions. Our work provides insights into the ecological implications of the effects of herbicides on the phyllosphere microbiome.Release of contaminants from sediments has been one of the main pollution sources causing eutrophication and malodorous black of ponds. In this study, an iron-rich substrate (IRS) was developed based on iron‑carbon micro-electrolysis and applied for simultaneous sediments and overlying water remediation. IRS obtained high ammonia and phosphate adsorption capacities (Langmuir isotherm) of 13.02 and 18.12 mg·kg-1, respectively. In the 90-day long-term remediation, IRS reduced NH4+-N, PO43–P, organic-N, organic-P, TN and TP in overlying water by 48.6%, 97.9%, 34.2%, 67.1%, 53.2% and 90.4%, respectively. In sediments, IRS reduced NO3–N, NH4+-N and organic-N by 98.5%, 26.5% and 6.3%, respectively. The unstable P-compounds (i.e., organic-P, Ca-bounded-P and labile-P) were effectively transferred (20.1%, 54.3% and 98.2%, respectively) into inert P-compounds (i.e., Fe-bounded-P and residual-P). Meanwhile, flux rates of nitrogen and phosphorus from sediments to overlying water were reduced from 7.02 to 4.92 mg·m-2·d-1 (by 29.9%) and from 7.42 to 2.21 mg·m-2·d-1 (by 70.2%), respectively. Capsazepine research buy Due to micro-electrolysis, Fe2+/Fe3+/[H] were in-situ generated from IRS and NO3–N was effectively reduced. Additionally, the generation of O2· was promoted by Fe2+/[H] and strengthened the NH4+-N, organic-N/P oxidation. Fe3+ enhanced the immobilization of PO43- (e.g., as FePO4·H2O and FenPO4(OH)3n-3). The released Fe2+/Fe3+ from IRS were finally stabilized as poorly reactive sheet silicate (PRS)-Fe and magnetite-Fe in the sediments and hardly showed side effect to sediments and water body. The developed IRS obtained advantages of high efficiency, ecologically safe and cost-effective in contaminated sediments and overlying water remediation.Due to the limited availability of freshwater supplies, desalination has become an increasingly reliable process for water supply worldwide, with proved technical and economic feasibility and advantages. Recently, desalination capacity significantly increased from approximately 35 million m3 daily (MCM/day) in 2005 to about 95 MCM/day in 2018. Seawater desalination accounts for about 61% of global desalination capacity, while brackish water desalination accounts for 30%. Membrane desalination, mainly using reverse osmosis (RO), accounts for ¾ of global desalination capacity, with the rest mostly used for thermal desalination using multi-stage flash distillation (MSF), and multi-effect distillation (MED). Despite the undeniable role of desalination for securing water supply in areas where natural freshwater supplies are scarce, desalination impacts the natural environment at different aspects. Environmental impacts (EIs) of the desalination process are different and vary significantly according to the nature of the utilized feedwater, the desalination technology in use, and the management of waste brine generated.