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Hydrothermal aqueous phase (HAP) contains abundant organics and nutrients, which have potential to partially replace chemical fertilizers for enhancing plant growth and soil quality. However, the underlying reasons for low available nitrogen (N) and high N loss in dryland soil remain unclear. A cultivation experiment was conducted using HAP or urea to supply 160 mg N kg−1 in dryland soil. The dynamic changes of soil organic matters (SOMs), pH, N forms, and N cycling genes were investigated. Results showed that SOMs from HAP stimulated urease activity and ureC , which enhanced ammonification in turn. The high-molecular-weight SOMs relatively increased during 5–30 d and then biodegraded during 30–90 d, which SUV 254 changed from 0.51 to 1.47 to 0.29 L−1 m−1. This affected ureC that changed from 5.58 to 5.34 to 5.75 lg copies g−1. Relative to urea, addition HAP enhanced ON mineralization by 8.40 times during 30–90 d due to higher ureC. It decreased NO 3 –N by 65.35%–77.32% but increased AOB and AOA by 0.25 and 0.90 lg copies g−1 at 5 d and 90 d, respectively. It little affected nirK and increased nosZ by 0.41 lg copies g−1 at 90 d. It increased N loss by 4.59 times. The soil pH for HAP was higher than that for urea after 11 d. The comprehensive effects of high SOMs and pH, including ammonification enhancement and nitrification activity inhibition, were the primary causes of high N loss. The core idea for developing high-efficiency HAP fertilizer is to moderately inhibit ammonification and promote nitrification. [Display omitted] • HAP relative to urea increased N loss by 4.59 times during 90 d cultivation. • HAP increased ureC during 30–90 d when high molecular weight DOMs biodegraded. • HAP increased AOA + AOB by 0.95 lg copies g−1 but decreased 65.35%–77.32% NO 3 –N. • HAP little changed nirK and increased nosZ by 0.41 lg copies g−1. • High soil pH and SOMs reasoned from HAP were the main reasons. [ABSTRACT FROM AUTHOR]

Chelator-assisted phytoremediation is an efficacious method for promoting the removal efficiency of heavy metals (HMs). The effects of N, N-bis(carboxymethyl)-L-glutamic acid (GLDA) and polyaspartic acid (PASP) on Cd uptake and pyrene removal by Solanum nigrum L. (S. nigrum) were compared in this study. Using GLDA or PASP, the removal efficiency of pyrene was over 98%. And PASP observably raised the accumulation and transport of Cd by S. nigrum compared with GLDA. Meanwhile, both GLDA and PASP markedly increased soil dehydrogenase activities (DHA) and microbial activities. DHA and microbial activities in the PASP treatment group were 1.05 and 1.06 folds of those in the GLDA treatment group, respectively. Transcriptome analysis revealed that 1206 and 1684 differentially expressed genes (DEGs) were recognized in the GLDA treatment group and PASP treatment group, respectively. Most of the DEGs found in the PASP treatment group were involved in the metabolism of carbohydrates, the biosynthesis of brassinosteroid and flavonoid, and they were up-regulated. The DEGs related to Cd transport were screened, and ABCG3 , ABCC4 , ABCG9 and Nramp5 were found to be relevant with the reduction of Cd stress in S. nigrum by PASP. Furthermore, with PASP treated, transcription factors (TFs) related to HMs such as WRKY , bHLH , AP2/ERF , MYB were down-regulated, while more MYB and bZIP TFs were up-regulated. These TFs associated with plant stress resistance would work together to induce oxidative stress. The above results indicated that PASP was more conducive for phytoremediation of Cd-pyrene co-contaminated soil than GLDA. [Display omitted] • Polyaspartic acid was more beneficial to improve phytoextraction of Cd. • Enhanced Cd transport by chelators was closely related to transcriptional regulation. • Polyaspartic acid regulated brassinosteroid, flavone and flavonol biosynthesis. • Chelators regulated transporter proteins and transcription factors gene expressions. [ABSTRACT FROM AUTHOR]

The effect of mix-cultured aerobic denitrifying microorganisms on the water remediation has been extensively explored, but little is known about the performance of mix-cultured low efficiency fungi on denitrification. In this study, two kinds of aerobic denitrifying fungi (Trichoderma afroharzianum H1 and Aspergillus niger C1) were isolated from reservoirs, improved the capacity by mix-cultured. The results showed a difference between northern and southern reservoirs, the dominants of genera were Cystobasidium and Acremonium. The removals of total nitrogen (TN) was 12.00%, 7.53% and 69.33% in Trichoderma afroharzianum H1, Aspergillus niger C1 and mix-cultured (C1 and H1) under the denitrification medium. The contents of ATP and electron transport system activity in mix-cultured amendment were increased by 42.54% and 67.52%, 1.72 and 2.91 times, respectively. Besides, the raw water experiment indicated that TN removals were 24.05%, 12.66% and 73.42% in Trichoderma afroharzianum H1, Aspergillus niger C1 and mix-cultured. The removals of dissolved organic carbon in mix-cultured were increased 35.02% and 50.46% compared to Trichoderma afroharzianum H1 and Aspergillus niger C1. Therefore, mix-cultured of two low efficiency aerobic denitrifying fungi has been considered as a novelty perspective for mitigation of drinking water source. • Trichoderma afroharzianum H1 and Aspergillus niger C1 were isolated from reservoirs. • Mix-cultured of two fungi improved the performance of aerobic denitrifying. • Mix-cultured could remove 69% total nitrogen and 93% of dissolved organic carbon. • The ATP and electron transport system activity were increased by mix-cultured. • Mix-cultured exhibited excellent nitrogen and carbon removal ability in raw water. [ABSTRACT FROM AUTHOR]

Flooding undermines the functionality of road links, leading to commute disruption, such as increased commuting time and immobility. Therefore, identifying the critical roads under different flood scenarios is of great significance for transportation planning to minimize flood risk. Previous studies on the road criticality under pluvial floods have focused on mostly structural characteristics of the roads, lacking the quantification of the flood impact on traffic. We employed an integrated framework coupling pluvial flood modeling with commute simulation to assess the criticality of flooded road links under three scenarios (10, 30, and 50 year floods). The output of the flood modeling was used to reconstruct the road network. The routes of each individual commuter under a business as usual (BAU) scenario and three flood scenarios were obtained from the commute simulation. As the flood return period increased, the distribution of traffic flow became more uneven. The road criticality assessment revealed that greater flood impact on roads was closely related to the proximity of water bodies, low-lying topography, and greater commute demands of the region and provided evidence to prioritize locations for interventions. This study helps understand the resilience of transportation systems during floods, thereby enabling practitioners to design effective strategic plans in terms of emergency response, risk management, and urban planning. • Developed the road criticality indicators to characterize the impact of road disruption on commutes during floods. • The distribution of traffic flow became more uneven as the flood return period increased. • The causes of impassable roads were spatially heterogeneous. • The road criticality indicators provided ground for prioritizing interventions. [ABSTRACT FROM AUTHOR]

Fe2O3-assisted pyrolysis has been demonstrated to be a cost-effective thermal desorption (TD) technology. Lurgi-Thyssen dust (LTD) is a type of steel slag waste that contains a large amount of Fe2O3. In this study, to reduce energy consumption, LTD was added to contaminated soil to evaluate the feasibility of enhancing the TD removal efficiency of di-(2-ethylhexyl) phthalate (DEHP). The DEHP removal rate increased by 22.39% after adding 2% LTD at 200 °C for 20 min. Because of the catalytic pyrolysis of LTD, DEHP was pyrolyzed to form three types of short-chain esters: mono-(2-ethylhexyl) phthalate (MEHP), di (2-methylbutyl) ester, and methyl 2-ethylhexyl phthalate. The pyrolysis products of DEHP were less toxic and did not affect soil reuse. When the DEHP removal rate was 87.10%, LTD addition decreased the temperature and residence time of TD and alleviated the effect of TD on the soil physicochemical properties. Additionally, the desorption of DEHP from soil fitted the pseudo-second-order kinetic model well. Thus, the addition of LTD to contaminated soil enhanced the efficiency of TD remediation. Moreover, this study could provide a practical and economical strategy for LTD reuse. • Thermal desorption of di (2-ethylhexyl) phthalate involved volatilization, pyrolysis. • Lurgi-Thyssen dust improved the thermal desorption remediation effect. • The catalysis includes alkyl bond breakage, ester hydrolysis, carboxyl methylation. [ABSTRACT FROM AUTHOR]