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141. 题目: Integrative effect of activated biochar to reduce water stress impact and enhance antioxidant capacity in crops
文章编号: N23091103
期刊: Science of the Total Environment
作者: Hiba Ghazouani, Khaled Ibrahimi, Roua Amami, Sondes Helaoui, Iteb Boughattas, Sabri Kanzari, Paul Milham, Sabah Ansar, Farooq Sher
更新时间: 2023-09-11
摘要:

Biochar is a soil amendment that can change soil's physical and hydraulic properties. However, biochar application is far from being a ‘one size fits-all’ approach. The impact of the management practices is dependent on biochar type (feedstock and production conditions), application depth and method, climate and site characteristics. Hence, this study aims to enrich the available no conclusive information on how biochar could affect clay loamy soil and to assess the potential impact of the induced change on water stress mitigation of rain-fed durum wheat under the specific condition of the semi-arid environment of North West of Tunisia. A field experiment was investigated in which three biochar rates 0 (B0), 10 (Equivalent to 0.5 % of weight) (B1) and 20 t/ha (Equivalent to 1 % of weight), (B2), were tested. Other laboratory analysis allowed the evaluation of soil water retention curve (SWRC), saturated hydraulic conductivity (Ks), dry density (ρ_b) and biostress biomarkers such as glutathione-S-transferase (GST), catalase activities (CAT) and malondialdehyde content (MDA) as well as yield attributes. Results showed that treatment B2 significantly decreased ${\rho }_b$ and Ks with relative change values of about −3.1 % and −19 %. Consequently, SWRC showed a better water retention capacity, mostly from saturation to matric potential value (h) of 33 KPa. Total (TAWC), plant (PAWC) and readily (RAWC) available water contents, significantly increased under B2 with relative changes of +6 %, +44 % and +44 % respectively. Moreover, GST and CAT were also boosted under B2. Consequently, biological and grain yields as well as grain water use efficiency (GWUE) significantly increased from 0.81 ± 0.04 in B0 to 1.09 ± 0.01 kg/m³ in B2. The correlation analysis showed a significant and positive correlation, between GWUE and soil water parameters (θs, θfc and θmre) suggesting the indirect effect of biochar on water-use efficiency for grain yield of wheat. Therefore, among the tested rates 20 t/ha could be suggested to improve plant soil water availability and reduce the harmful impact of drought stress on rainfed durum wheat.

142. 题目: The adsorption of biogenetic odorants onto activated carbon: Adsorption characteristics and impacts of algal organic matter
文章编号: N23091102
期刊: Environmental Research
作者: Junzhi Zhang, Fan Lu, Xiao He, Yu Liao, Rumeng Chen, Rongjun Xia, Yuchen Shang, Qi Wang, Jianwei Yu
更新时间: 2023-09-11
摘要:

Powdered activated carbon (PAC) adsorption is regarded as an efficient method for removing odorants from drinking water. However, in eutrophic aquatic environments, the presence of algal organic matter (AOM) produced by cyanobacteria considerably impedes the adsorption of odorous compounds by activated carbon. This study focused on investigating the adsorption characteristics of three representative odorants: 2-methylisoborneol (2-MIB), β-cyclocitral (β-cyclo), and butyl sulfide (BS) by PAC and the effects of AOM on the PAC adsorption of odorants. The removal of the three odorants reached 83.5–97.5% at a PAC dosage of 10 mg/L after 12 h of exposure in a competition-free scenario. The adsorption kinetics demonstrated higher conformity (R² > 0.9) with the pseudo-second-order model, whereas the adsorption capacity exhibited stronger conformity (R² > 0.9) with the Freundlich model. The presence of AOM resulted in varying levels of competition for PAC for the adsorption of the three odorants. As the concentration of AOM increased from 0 to 5 mg C/L, the removal of 2-MIB was the most affected (from 83.5% to 10.0%), followed by β-cyclo (from 86.6% to 55.0%), and BS (from 97.5% to 92.0%). The competitive adsorption of AOM at the molecular level was studied using density functional theory (DFT). The DFT results suggested that odorants with higher and more uniformly distributed electrostatic potentials exhibited a heightened affinity for PAC adsorption and a diminished susceptibility to disruption caused by AOM. This study provides valuable insights into the mitigation of odorous compounds during drinking water purification.

143. 题目: Patterns and driving factors of soil organic carbon sequestration efficiency under various manure regimes across Chinese croplands
文章编号: N23091101
期刊: Agriculture, Ecosystems & Environment
作者: Fengling Ren, Ruqiang Zhang, Nan Sun, Yalin Li, Minggang Xu, Fusuo Zhang, Wen Xu
更新时间: 2023-09-11
摘要:

The carbon sequestration efficiency of manure (CSE-manure) is critical for the accurate estimation of manuring-induced changes in soil organic carbon (SOC). However, the mechanisms of large-scale spatiotemporal changes in CSE-manure and their crucial drivers are unclear. To investigate these under various manure regimes, we performed field observation and collected relevant data using 1023 fields across China’s main cropland, as well as collected data on high-resolution climate and soil properties. The experimental durations significantly (P < 0.001) affected CSE-manure. The CSE-manure values were 31.4% ± 13.4 (mean ± SD), 19.2% ± 10.3%, and 16.1% ± 9.4 at the experimental durations of < 10, 10–20, and > 20 years, respectively. In addition, the manure sources significantly affected CSE-manure. The CSE-manure values of the manures from horse (27.9% ± 19.0) and sheep (26.9% ± 11.0) and farmyard manure (25.7% ± 14.8) were higher than those of the manures from pig (19.8% ± 15.4), poultry (19.1% ± 10.58), and cattle (23.1% ± 13.1). The CSE-manure values varied as per the region; the values were higher in North China than in South China. Of all the investigated variables, carbon and nitrogen input from manure, soil bulk density, annual average air temperature and precipitation, and initial SOC and soil clay content were the most important drivers of CSE-manure. The results suggested that carbon sequestration potential was higher in the northeast region. The spatiotemporal CSE-manure values under various climate conditions were predicted using trained machine learning models. Simulation results suggested that by 2100, the rate of decrease in CSE-manure will be higher at RCP (Representative Concentration Pathways) 8.5, and climate change will have a great impact on CSE-manure due to high warming effects.

144. 题目: Root but not shoot litter fostered the formation of mineral-associated organic matter in eroded arable soils
文章编号: N23091007
期刊: Soil and Tillage Research
作者: Eva Kaštovská, Michal Choma, Gerrit Angst, Rainer Remus, Jürgen Augustin, Steffen Kolb, Stephan Wirth
更新时间: 2023-09-10
摘要:

Erosion leads to a decline in carbon (C) stocks in arable soils and negatively impacts soil functions worldwide. For soil restoration, it is critical to identify the factors that link crop residue quality to effective C sequestration in the soil, primarily through the formation of mineral-associated organic matter (MAOM) and through incorporation into aggregates (oPOM). The widely accepted concept links effective C stabilization with input of high-quality substrates, but studies of C-deficient soils do not support this assumption. Therefore, we aimed to determine the potential of eroded arable soils to stabilize C from barley shoot and root residues, which represent high- and low-quality inputs, respectively. In a year-long laboratory experiment, we added the residues to two soil pairs (eroded and non-eroded) with different soil textures, observed the formation of oPOM and MAOM and identified microbial groups important for substrate transformation. We found that eroded soils retained added residues very efficiently (35–65% bound residue C), making them a high-priority target for C sequestration. Root residues caused more efficient MAOM formation than shoot residues, primarily by direct binding of depolymerized root-C to mineral surfaces without subsequent microbial transformation. This root C stabilization in MAOM was more pronounced in eroded (highly C-undersaturated) soils than in non-eroded soils and in fine-textured soils, which provided more space for microbial colonization and C sorption, than in coarse-textured soils. Shoot residues were decomposed and metabolized by a microbiome rich in efficient bacterial decomposers (Actinobacteria, Xanthomonadales). This led to inevitably higher C losses related to their growth and biomass turnover, and probably also to an intense priming effect on pre-existing MAOM that lowered the efficiency of MAOM formation. Our results argue for crops with robust root systems, or for the inclusion of deep-rooted plants in crop rotations, which could help rapidly restore the C stocks in arable soils.

145. 题目: Effects of Climate Change on Soil Organic Matter C and H Isotope Composition in a Mediterranean Savannah (Dehesa): An Assessment Using Py-CSIA
文章编号: N23091006
期刊: Environmental Science & Technology
作者: Layla M San-Emeterio, Lorena M Zavala, Nicasio T Jiménez-Morillo, Ignacio M Pérez-Ramos, José A González-Pérez
更新时间: 2023-09-10
摘要: Dehesas are Mediterranean agro-sylvo-pastoral systems sensitive to climate change. Extreme climate conditions forecasted for Mediterranean areas may change soil C turnover, which is of relevance for soil biogeochemistry modeling. The effect of climate change on soil organic matter (SOM) is investigated in a field experiment mimicking environmental conditions of global change scenarios (soil temperature increase, +2–3 °C, W; rainfall exclusion, 30%, D; a combination of both, W+D). Pyrolysis-compound-specific isotope analysis (Py-CSIA) is used for C and H isotope characterization of SOM compounds and to forecast trends exerted by the induced climate shift. After 2.5 years, significant δ¹³C and δ²H isotopic enrichments were detected. Observed short- and mid-chain n-alkane δ¹³C shifts point to an increased microbial SOM reworking in the W treatment; a ²H enrichment of up to 40‰ of lignin methoxyphenols was found when combining W+D treatments under the tree canopy, probably related to H fractionation due to increased soil water evapotranspiration. Our findings indicate that the effect of the tree canopy drives SOM dynamics in dehesas and that, in the short term, foreseen climate change scenarios will exert changes in the SOM dynamics comprising the biogeochemical C and H cycles.

146. 题目: Effect of organic carbon structures on the degradation of nonylphenol by hydrogen peroxide in sediment–water system
文章编号: N23091005
期刊: Journal of Environmental Quality
作者: Yongli Zhang, Xianglan Kong, Yu Yang, Yong Ran
更新时间: 2023-09-10
摘要: A laboratory experiment is conducted to investigate the effects of organic carbon (OC) from riverine and marine sediments on the degradation of ring-¹⁴C labeled nonylphenol (¹⁴C-NP) by hydrogen peroxide (H₂O₂). Researchers have isolated demineralized OC before and after oxidation, namely demineralized OC (DM) and resistant OC (ROC) fractions, respectively. The structures of DM and ROC are characterized using solid-state ¹³C nuclear magnetic resonance. Unstable structures (O-alkyl, OCH₃/NCH, and COO/NC = O) show a significant and positive correlation with the degradation of ¹⁴C-NP (R² > 0.73, p < 0.05), thus suggesting that the NP absorbed in the unstable structures are easily degraded because of the decomposition of unstable components. The stable structures (alkyl C and non-protonated aromatic C (Arom C-C)) exhibit a significant and negative correlation with the degradation of ¹⁴C-NP (R² > 0.69, p < 0.05), thus suggesting that the NP absorbed and protected in these resistant structures are minimally degraded. The significant correlations among the degradation kinetic parameters (F_rap and F_slow), OC structures (F_alip and F_arom), and microporosity further illustrate the important protective roles of OC structures and micropores in the degradation of ¹⁴C-NP by H₂O₂ (R² > 0.69, p < 0.05). The parent NP fraction that desorbed into the aqueous solution or extracted is completely degraded, indicating preferential degradation of the easily desorbed NP. This study provides important insights into the NP degradation mechanism in sediment–water systems, particularly regarding sediment OC structures and microporosity.

147. 题目: Effective immobilization of bisphenol A utilizing activated biochar incorporated into soil: combined with batch adsorption and fixed-bed column studies
文章编号: N23091004
期刊: Environmental Science and Pollution Research
作者: Fengying Wu, Xiangyi Gong, Dekang Meng, Hao Li, Dajun Ren, Jiaquan Zhang
更新时间: 2023-09-10
摘要:

This study presented the mixture of biochar and soil for removal of bisphenol A (BPA) to assess environmental remediation ability. Using phoenix tree leaves as biomass and phosphoric acid as activator, after one-step hydrothermal and short-term activation, the eventual solid product was phosphoric acid hydrothermal activated carbon (HPC). The characterizations showed that HPC had the high specific surface (994.21 m²·g⁻¹), and large unsaturated esters and hydroxyl groups. The saturated adsorption capacities of batch and column adsorption for the addition of 0.5% HPC to soil were 0.790 mg·g⁻¹ and 67.23 mg·kg⁻¹, while to the natural soil were 0.236 mg·g⁻¹ and 8.75 mg·kg⁻¹, respectively. The adsorption kinetics and thermodynamic analysis indicated that the adsorption process utilizing HPC incorporated into soil was a chemical reaction rate-controlled, physical-dominated multilayer adsorption, and spontaneous endothermic. Also, batch adsorption experiments and analysis were performed under different pH levels, HPC contents, organic acid concentrations, and cationic strengths. Successively, fixed-bed column experiments were carried out with and without the HPC; the results showed that the wide mass transfer zone led to the effective fixation of BPA, and the organic acid had no obvious effect on the fixation of BPA when the 1.0% HPC mixed with soil. Finally, through characterizations and data analysis, the enhanced adsorption of BPA by HPC mixed with soil mainly relied on π-π interaction, hydrogen bonding, followed by electrostatic attraction and pore filling.

148. 题目: Application of fractional-order differential and ensemble learning to predict soil organic matter from hyperspectra
文章编号: N23091003
期刊: Journal of Soils and Sediments
作者: Ya Liu, Yuewen Zhang, Huizhong Lu, Yong Yang, Jingying Xie, Danyan Chen
更新时间: 2023-09-10
摘要:

Purpose

Accurate estimation of soil organic matter (SOM) content is crucial for agricultural production. The integral-order differential hyperspectral processing might easily lead to the loss of trace hyperspectral information of substances, especially in moist condition. The aim of this study was to propose a method which can enhance the characteristics of SOM and improve the prediction accuracy of SOM in moist condition.

Materials and methods

This study firstly used the fractional-order differential (FOD) technique to refine the hyperspectral information, performing 0 ~ 2 order differential preprocessing on the hyperspectral spectrum with a step of 0.1, and then, the significance level at 0.05 was taken to complete the screening. Afterwards, traditional machine learning algorithms (partial least squares regression) and ensemble learning algorithms (eXtreme gradient boosting (XGBoost), light gradient boosting machine (LightGBM), and random forest (RF)) were applied to predict SOM content. Based on 21 different differential orders and 4 learning algorithms, a total of 84 models were established. Coefficient of determination (R²), root mean square error (RMSE), residual prediction deviation (RPD), and Lin’s consistency correlation coefficient (LCCC) were used to evaluate the prediction accuracy. Standard deviation was applied to represent the uncertainty of the models.

Results and discussion

The results showed that FOD processing of hyperspectra could effectively mine highly efficacious information and improve prediction accuracy of SOM. The best model was believed to be the XGBoost algorithm with 0.8-order differential, and its values of ({R}_{t}^{2},,{mathrm{RMSE}}_{t},,{mathrm{RPD}}_{t},,mathrm{and}, {mathrm{LCCC}}_{t}) were 0.81 ± 0.02, 6.95 ± 0.31 g kg⁻¹, 2.24 ± 0.02, and 0.90 ± 0.01, respectively.

Conclusions

Briefly, FOD showed tremendous potential in enhancing spectral characteristics of SOM; its combination with ensemble learning can improve the prediction accuracy of SOM. Furthermore, it also provides a new approach to rapidly and accurately acquire other soil attributes.

149. 题目: Spatial Variation and Influencing Factors of Optical Characteristic of Water Extractable Organic Matter in Soils of Urban Grassland Across Climatic Zones in China
文章编号: N23091002
期刊: Aquatic Geochemistry
作者: Baozhu Pan, Siwan Liu, Yitong Ding, Ming Li
更新时间: 2023-09-10
摘要:

Dissolved organic matter (DOM) is the most active organic component in terrestrial ecosystems. In this study, 165 soil samples which were dominated by moss were collected from grasslands with similar vegetation in urban residential areas from 55 cities across different climatic zones of China. The water extractable organic matter (WEOM) of samples was analyzed. The results showed that WEOM content ranged from 23.5 to 517.6 mg kg⁻¹ in the soil samples. Four fluorescent components including two tryptophan-like components (C1 and C4) and two humic-like components (C2 and C3) were identified by excitation–emission matrices combined with parallel factor analysis (EEM-PARAFAC). Proportions of humic-like components (C2 + C3) were 54–66%, which is 1.2–2.0 times of the tryptophan-like component proportion (C1 + C4) for all samples. The proportions of C2 and C3 were highest in the tropical monsoon climate (TroM) zone compared to that in the other climatic zones. Structural equation model and decomposition of variation showed that soil nutrient content was the main contributing factor of soil WEOM. Content Total nitrogen content and mean annual temperature (MAT) were the main factors influencing soil HIX but they had the opposite effects. Our results suggested that increasing soil nutrient content contributed the increase in soil WEOM content, but increasing MAT reduced the humification degree of WEOM.

150. 题目: Anaerobic methanotrophy is stimulated by graphene oxide in a brackish urban canal sediment
文章编号: N23091001
期刊: Environmental Microbiology
作者: Koen A J Pelsma, Niels A G M van Helmond, Wytze K Lenstra, Thomas Röckmann, Mike S M Jetten, Caroline P Slomp, Cornelia U Welte
更新时间: 2023-09-10
摘要: Anthropogenic activities are influencing aquatic environments through increased chemical pollution and thus are greatly affecting the biogeochemical cycling of elements. This has increased greenhouse gas emissions, particularly methane, from lakes, wetlands, and canals. Most of the methane produced in anoxic sediments is converted into carbon dioxide by methanotrophs before it reaches the atmosphere. Anaerobic oxidation of methane requires an electron acceptor such as sulphate, nitrate, or metal oxides. Here, we explore the anaerobic methanotrophy in sediments of three urban canals in Amsterdam, covering a gradient from freshwater to brackish conditions. Biogeochemical analysis showed the presence of a shallow sulphate–methane transition zone in sediments of the most brackish canal, suggesting that sulphate could be a relevant electron acceptor for anaerobic methanotrophy in this setting. However, sediment incubations amended with sulphate or iron oxides (ferrihydrite) did not lead to detectable rates of methanotrophy. Despite the presence of known nitrate-dependent anaerobic methanotrophs (Methanoperedenaceae), no nitrate-driven methanotrophy was observed in any of the investigated sediments either. Interestingly, graphene oxide stimulated anaerobic methanotrophy in incubations of brackish canal sediment, possibly catalysed by anaerobic methanotrophs of the ANME-2a/b clade. We propose that natural organic matter serving as electron acceptor drives anaerobic methanotrophy in brackish sediments.

151. 题目: Evaluating effects of biochar on anaerobic digestion of dewatered waste activated sludge: Digester performance, microbial co-metabolism and underlying mechanism
文章编号: N23090904
期刊: Chemosphere
作者: Dunjie Li, Qian Ping, Wenjie Guo, Yifeng Chen, Lin Wang, Yongmei Li
更新时间: 2023-09-09
摘要:

Biochar has been proven to be capable of improving the performance of anaerobic digestion (AD). However, the effect of biochar on microbial communities remains ambiguous. In this study, the influence of pH was excluded in a semi-continuous anaerobic digestor for the treatment of dewatered waste activated sludge (WAS) to determine the effect of biochar on microbes. Compared with the control group, the average methane production increased by 24.5% and 23.2% at the organic loading rates (OLRs) of 1.56 and 3.00 gTS/L/d, respectively, in the presence of biochar. This study innovatively found biochar accelerated the enrichment of Methanofastidiosaceae, which competed with Methanobacteriaceae for H₂, and its abundance increased from 0.99% at the OLR of 1.56 g TS/L/d to 16.57% and 38.11% at the OLR of 3.00 and 5.60 gTS/L/d, respectively. The efficient metabolic network of f__norank_o__Aminicenantales, syntrophic bacteria, Methanofastidiosaceae and Methanosaetaceae promoted the conversion of WAS to CH₄ in the biochar group. In addition, metagenome analysis revealed that biochar optimized the metabolites related to energy conservation and electron transfer, particularly for hydrogenase (frhABG, mbhLHK and hndA-D), confirming that biochar changed the way H₂ was involved in methanogenesis. These findings provide novel insights into the direct effect of biochar on microbial evolution and facilitate the reduction of WAS to achieve higher economic benefits in biogas production.

152. 题目: Fe-loaded biochar thin-layer capping for the remediation of sediment polluted with nitrate and bisphenol A: Insight into interdomain microbial interactions
文章编号: N23090903
期刊: Environmental Pollution
作者: Yiheng Zhao, Xing Hou, Longfei Wang, Linqiong Wang, Bian Yao, Yi Li
更新时间: 2023-09-09
摘要:

The information on the collaborative removal of nitrate and trace organic contaminants in the thin-layer capping system covered with Fe-loaded biochar (FeBC) is limited. The community changes of bacteria, archaea and fungi, and their co-occurrence patterns during the remediation processes are also unknown. In this study, the optimized biochar (BC) and FeBC were selected as the capping materials in a batch experiment for the remediation of overlying water and sediment polluted with nitrate and bisphenol A (BPA). The community structure and metabolic activities of bacteria, archaea and fungi were investigated. During the incubation (28 d), the nitrate in overlying water decreased from 29.6 to 11.0 mg L⁻¹ in the FeBC group, 2.9 and 1.8 times higher than the removal efficiencies in Control and BC group. The nitrate in the sediment declined from 5.03 to 0.75 mg kg⁻¹ in the FeBC group, 1.3 and 1.1 times higher than those in Control and BC group. The BPA content in the overlying water in BC group and FeBC group maintained below 0.4 mg L⁻¹ during incubation, signally lower than in the Control group. After capping with FeBC, a series of species in bacteria, archaea and fungi could collaboratively contribute to the removal of nitrate and BPA. In the FeBC group, more metabolism pathways related to nitrogen metabolism (KO00910) and Bisphenol degradation (KO00363) were generated. The co-occurrence network analysis manifested a more intense interaction within bacteria communities than archaea and fungi. Proteobacteria, Firmicutes, Actinobacteria in bacteria, and Crenarchaeota in archaea are verified keystone species in co-occurrence network construction. The information demonstrated the improved pollutant attenuation by optimizing biochar properties, improving microbial diversity and upgrading microbial metabolic activities. Our results are of significance in providing theoretical guidance on the remediation of sediments polluted with nitrate and trace organic contaminants.

153. 题目: Amelioration of a saline-alkaline soil using biochar and compost: Impacts on plant growth, soil biological and chemical characteristics
文章编号: N23090902
期刊: Land Degradation & Development
作者: Cassandra R Howell, Sasha N Jenkins, Lynette K Abbott, Bede S Mickan
更新时间: 2023-09-09
摘要: Land degradation reduces productivity and biodiversity, and requires restoration of both soil condition and vegetation to re-establish ecosystem services. Organic amendments can improve soil biological and chemical properties, thereby enhancing revegetation success in severely degraded soil. This study investigated the use of compost and biochar to support revegetation and soil restoration. Soil was collected from a severely degraded creek bed in an agricultural farm in south-western Australia (UWA Farm Ridgefield) and amended with compost (2.5% and 5%) and biochar (5% and 10%), both alone and in all pairwise combinations. Saltbush (Atriplex nummularia) seedlings were grown for 10 weeks in glasshouse conditions. Following harvest, plant growth and soil chemical properties were analysed. DNA was extracted from rhizosphere soil for bacterial diversity profiling with subsequent putative functional genes relating to carbon, nitrogen and phosphorus cycling using an in-silico approach. Compost improved growth of root and shoot biomass. Both compost and biochar improved the alkaline soil by reducing pH and increasing nitrate, phosphorus and potassium levels. Compost addition also had a significant effect on rhizosphere bacterial community structure, decreasing alpha diversity and altering beta diversity indices. Amendment of soil also changed the relative abundance of putative nutrient cycling genes, with an increase in the potential for denitrification, carbon and phosphorus cycling and a decrease in ammonification potential. Application of this compost-biochar combination improved plant growth and soil condition by altering both chemical and biological characteristics of the soil, and therefore may provide an effective management strategy for supporting restoration in a degraded landscape.

154. 题目: EARLY DECOMPOSITION AND TRANSFORMATION OF ORGANIC MATTER IN NATURAL AND DISTURBED BOREAL FORESTS
文章编号: N23090901
期刊: Organic Geochemistry
作者: Anjelica Kondratova, Irina Kotel'nikova, Elizaveta Susloparova, Tatiana Yurkova, Semyon Bryanin
更新时间: 2023-09-09
摘要:

The state of boreal larch forests near the southern permafrost margin in eastern Eurasia varies considerably, even on a local scale, as a result of anthropogenic disturbances (e.g., clear-cuts and fires) and uneven permafrost distribution. This study aimed to investigate whether various ecosystem conditions affect litter decomposition and organic matter (OM) transformation. Here, we present the results of the field experiment in natural and disturbed larch stands utilising the Tea-Bag Index approach (TBI). We investigated the decomposition in 4 larch stands in different states (post-fire, clear-cut, permafrost and control). Besides standard TBI indexes, we studied the transformation of OM composition by thermochemolysis–gas chromatography mass spectrometry. Mass loss differed depending on litter quality rather than forest disturbance type or permafrost. No significant differences were found between stabilisation (S) and decomposition constant (k) in disturbed and unaffected forests, whereas soil properties were differently related to decomposition parameters on study sites. Our results on molecular composition before and after the incubation suggest site-depending, mainly microbial transformation of green tea in various forest conditions. Rooibos did not undergo a considerable microbial transformation. We showed that S and k might not be sensitive to various ecosystem conditions (e.g., disturbances and permafrost). However, the transformation of OM may vary, even on a local scale, having significant implications for carbon sequestration in soil. Our study shows that not a mass loss but a transformation of OM might depend on various conditions of the larch ecosystem at the southern margin of permafrost distribution in eastern Eurasia.

155. 题目: The influence of pH and dissolved organic carbon on the ecotoxicity of ampicillin and clarithromycin
文章编号: N23090810
期刊: Science of the Total Environment
作者: Qiyun Zhang, Kristof Demeestere, Karel A C De Schamphelaere
更新时间: 2023-09-08
摘要:

The impacts of water chemistry properties including pH and dissolved organic carbon (DOC) on the ecotoxicity of active pharmaceutical ingredients (APIs) are increasingly evident. These impacts are a result of alterations in API bioavailability: pH regulates the bioavailability of many ionizable APIs via chemical speciation, whereas DOC interacts with several APIs to inhibit the APIs from traversing the membrane system of organisms. In this study, we examined the influences of pH and DOC on the bioavailability of ampicillin (AMP) and clarithromycin (CLA) with the help of a bioavailability model. The effects on bioavailability were quantified by ecotoxicity observed in cyanobacteria growth inhibition tests with Microcystis aeruginosa PCC7806. The median effect concentration (96 h-EC50_total) of AMP increased by 5-fold when pH raised from 7.4 to 9.0, suggesting the zwitterionic AMP^+/− species being higher in bioavailability than the negatively charged AMP⁻ species. CLA ecotoxicity showed no significant pH-dependency, suggesting CLA⁺ and CLA⁰ species to be equally bioavailable, albeit it correlated significantly with M. aeruginosa growth rate in negative controls. In addition, DOC demonstrated no significant effects on the ecotoxicity of AMP or CLA. Overall, together with earlier results on ciprofloxacin, our data show that bioavailability relations with pH and DOC are variable among different antibiotics. Factors other than chemical speciation alone could play a role in their bioavailability, such as their molecular size and polarity.

156. 题目: Effect of soil microbial community structure on the chemical compositions of different soil organic matter fractions in land uses of the Pearl River Estuary
文章编号: N23090809
期刊: Applied Soil Ecology
作者: Chun Liu, Zhinan Wu, Chunhuan He, Yuheng Zhang, Feifei Dong, Weijia Huang
更新时间: 2023-09-08
摘要:

Understanding the interactions between the dynamics of soil organic matter (SOM) and soil microbial communities is important for predicting the stability and fate of estuarine SOM following anthropogenic disturbance. However, current knowledge on the influence of microbial communities on the chemical compositions of different SOM fractions in estuarine land uses still remains incomplete. In this study, we used high-throughput sequencing, Fourier transform infrared spectroscopy, UV–Vis absorption, and fluorescence spectroscopy to investigate soil microbial communities and characterize the chemical compositions of bulk SOM and water-extractable organic matter (WEOM) across different land uses (artificial forests (AF), farmland (FL), natural wetland (NW), construction land (CL), and abandoned land (AL)) in the Pearl River Estuary. The results showed that the bulk SOM in FL and AL exhibited comparable or higher levels of aromatic functional groups (aromatic CH and aromatic CC) compared to other land uses. The HIX and SUV₂₅₄ indexes further confirmed that AF and FL had more aromatic and hydrophobic WEOM. Apart from FL, where anthropogenic humus constituted the largest proportion, the WEOM fraction predominantly consist of three components in the following order across all land uses, ordered as anthropogenic humus < microbial humus < protein humus. The chemical compositions of the different SOM fractions showed a stronger correlation with the dominant bacterial phylum composition, especially for the WEOM fraction, compared to the fungal composition. Meanwhile, our findings demonstrate that bacterial diversity showed a stronger relationship with the chemical composition of WEOM compared to abundance. Overall, this study sheds light on the impact of land use on the quantity and quality of SOM fractions, underscoring the varying influence of microorganisms on the chemical compositions of different SOM fractions within estuarine environments.

157. 题目: High resolution mapping shows differences in soil carbon and nitrogen stocks in areas of varying landscape history in Canadian lowland tundra
文章编号: N23090808
期刊: Geoderma
作者: Julia Wagner, Victoria Martin, Niek J Speetjens, Willeke A'Campo, Luca Durstewitz, Rachele Lodi, Michael Fritz, George Tanski, Jorien E Vonk, Andreas Richter, Annett Bartsch, Hugues Lantuit, Gustaf Hugelius
更新时间: 2023-09-08
摘要:

Soil organic carbon (SOC) in Arctic coastal polygonal tundra is vulnerable to climate change, especially in soils with occurrence of large amounts of ground ice. Pan-arctic studies of mapping SOC exist, yet they fail to describe the high spatial variability of SOC storage in permafrost landscapes. An important factor is the landscape history which determines landform development and consequently the spatial variability of SOC. Our aim was to map SOC stocks, and which environmental variables that determine SOC, in two adjacent coastal areas along Canadian Beaufort Sea coast with different glacial history. We used the machine learning technique random forest and environmental variables to map the spatial distribution of SOC stocks down to 1 m depth at a spatial resolution of 2 m for depth increments of 0–5, 5–15, 15–30, 30–60 and 60–100 cm.

The results show that the two study areas had large differences in SOC stocks in the depth 60–100 cm due to high amounts of ground ice in one of the study areas. There are also differences in variable importance of the explanatory variables between the two areas. The area low in ground ice content had with 66.6 kg C/m⁻² more stored SOC than the area rich in ground ice content with 40.0 kg C/m⁻². However, this SOC stock could be potentially more vulnerable to climate change if ground ice melts and the ground subsides. The average N stock of the area low in ground ice is 3.77 kg m⁻² and of the area rich in ground ice is 3.83 kg m⁻².

These findings support that there is a strong correlation between ground ice and SOC, with less SOC in ice-rich layers on a small scale. In addition to small scale studies of SOC mapping, detailed maps of ground ice content and distribution are needed for a validation of large-scale quantifications of SOC stocks and transferability of models.

158. 题目: Synthesis and characterization of nanobiochar from rice husk biochar for the removal of safranin and malachite green from water
文章编号: N23090807
期刊: Environmental Research
作者: Sadia Aziz, Bushra Uzair, Muhammad Ishtiaq Ali, Sundas Ambreen, Fatiha Umber, Muneeba Khalid, Alaa A A Aljabali, Yachana Mishra, Vijay Mishra, Ãngel Serrano-Aroca, Gowhar A Naikoo, Mohamed El-Tanani, Shafiul Haque, Abdulmajeed G Almutary, Murtaza M Tambuwala
更新时间: 2023-09-08
摘要:

Xenobiotic pollution in environment is a potential risk to marine life, and human health. Nanobiotechnology is an advanced and emerging solution for the removal of environmental pollutants. Adsorption-based technologies are being used to alleviate the global prevalence of xenobiotics like dyes, due to their high efficacy and cost effectiveness. Current study explored the potential of nanobiochar syntehsized via ultrasonication and centrifugation from rice husk for dye removal from water. It involves the synthesis of nanobiochar from rice husk biochar for removal of Safranin, Malachite green, and a mixture of both from aqueous water. Biochar was synthesized through pyrolysis at 600 °C for 2 h. To convert it into nanobiochar, sonication and centrifugation techniques were applied. The yield obtained was 27.5% for biochar and 0.9% for nanobiochar. Nanobiochar analysis through Fourier-Transform Spectrometer (FTIR), X-ray Power Diffraction (XRD) and scanning electron microscopy (SEM) suggested its crystalline nature having minerals rich in silicon, with a cracked and disintegrated carbon structure due to high temperature and processing treatments. Removal of dyes by nanobiochar was evaluated by changing different physical parameters i.e., nanobiochar dose, pH, and temperature. Pseudo-first order model and pseudo-second order model were applied to studying the adsorption kinetics mechanism. Kinetics for adsorption of dyes followed the pseudo-second order model suggesting the removal of dyes by process of chemical sorption. High adsorption was found at a higher concentration of nanobiochar, high temperature, and neutral pH. Maximum elimination percentages of safranin, malachite green, and a mixture of dyes were obtained as 91.7%, 87.5%, and 85% respectively. We conclude that nanobiochar could be a solution for dye removal from aqueous media.

159. 题目: Effects of sedimentary organic matter degradation and structure on nonylphenol degradation by sodium persulfate
文章编号: N23090806
期刊: Science of the Total Environment
作者: Yongli Zhang, Xianglan Kong, Yu Yang, Yong Ran
更新时间: 2023-09-08
摘要:

The structure and constituents of sedimentary organic matter (SOM) in the degradation of benzene ring-¹⁴C labeled 4-nonylphenol (¹⁴C-NP) by sodium persulfate (Na₂S₂O₈) were investigated. Na₂S₂O₈ mineralized over 84 % of ¹⁴C-NP to ¹⁴CO₂, and no parent unlabeled 4-nonylphenol (NP) compounds were detected in the water-soluble/supernatant phase or extractable residues. Organic carbon (OC) was sequentially separated from six sediment samples collected from the Pearl River (BET), estuary (GSD), continental shelf (S11 and S21), and deep sea (M9 and M10). Demineralized OC (DM), unstable OC (USOC), nonhydrolyzable OC (NHC), and resistant OC (ROC) were obtained and characterized using solid-state ¹³C nuclear magnetic resonance (SS-NMR). The correlations among USOC, NHC, and the degradation kinetic constant of ¹⁴C-NP (k_NP) were significant (R² > 0.86, p < 0.01), indicating that USOC and NHC were the main factors controlling ¹⁴C-NP degradation. SOM structure and constituent analyses indicated that O-alkyl C + OCH₃/NCH C + COO/NC=O C and carbohydrate + protein were positively related to Ln(k_NP) (R² > 0.72, p < 0.05) because these structures were unstable. However, the stable structures (Alkyl C and Arom CC) and constituents (sporopollenin, algaenan, and char) hindered ¹⁴C-NP degradation because they were negatively related to Ln(k_NP) (R² > 0.81, p < 0.05). The OC removal rate was positively correlated with ¹⁴C-NP degradation (R² > 0.86, p < 0.01), indicating that the NP was primarily degraded in parallel with the breakdown of SOM. Stoichiometric analysis showed that Na₂S₂O₈ effectively oxidized over 58 % of the OC to CO₂, and the electron transfer efficiency was 17.2–69.5 %. This study is the first to emphasize the importance of SOM degradation, structure, and constituents in the degradation of NP by persulfate.

160. 题目: Application of functionalized biochar for adsorption of organic pollutants from environmental media: Synthesis strategies, removal mechanisms and outlook
文章编号: N23090805
期刊: Journal of Cleaner Production
作者: Jianhua Qu, Qingjuan Meng, Wei Peng, Jiajia Shi, Zonghao Dong, Zhuoran Li, Qi Hu, Guangshan Zhang, Lei Wang, Shouyi Ma, Ying Zhang
更新时间: 2023-09-08
摘要:

Biochar (BC) is attracting increasing concerns on the scavenging of toxic contaminants from water because of its low-cost and environmental-friendly properties, however, the adsorption performance of pristine BC for common organic contaminants. Consequently, adopting available modification methods to strengthen the uptake performance of BC is necessary, unfortunately, there are few summaries on various functionalization techniques of BC with corresponding mechanisms on removing organic contaminants. Herein, this review aims to describe (i) the preparation methods of pristine BC and the influence of different pyrolysis parameters; (ii) various modification techniques for BC including liquid modification, gas modification, ball milling modification, metal nanoparticles loading, and near-nature BC-based immobilized materials; (iii) the applications of functionalized BC on organic pollutants removal with related adsorption mechanisms (iv) crucial factors (e.g. solution pH, contact time, and co-existing ions); influencing the removal process of functionalized BC on organic contaminants with application potential of modified BC as an adsorbent in environmental fields; (v) some useful and constructive proposals to improve the practical application of functionalized BC in future research. This review advanced the comprehensive understanding of application of functionalized BC as effective adsorbent with low-cost and high-performance properties for the remediation of contaminated water.