24年12月24日文献情报（7篇）

24年12月24日文献情报

1. 题目: Effects of long-term conservation tillage on soil aggregate carbon fractions and microbial characteristics under rice-oilseed rape rotation systems

文章编号: N24122407
期刊: Applied Soil Ecology
作者: Yanshi Li, Lijin Guo, Mengqin Wu, Chengfang Li
更新时间: 2024-12-24
摘要: Previous research on the impact of long-term conservation tillage on soil organic carbon (SOC) has primarily concentrated on bulk soil. However, there is a scarcity of studies that assess the effects of long-term conservation tillage on SOC and organic carbon (C) fractions within different aggregates. Consequently, a 9-year field experiment was conducted to investigate the changes in SOC fractions and microbial community, as well as their interrelationships within different aggregates under different tillage practices and residue management in a rice-oilseed rape rotation system. There were four treatments, including double crops with no-tillage (NT) and residue mulch (ORNS), double crops with NT and no residue (ORN), single crop with conventional tillage (CT) and no residue (ONRC), and double crops with CT and no residue (ORC). Long-term conservation tillage significantly increased the proportion of >250 μm aggregates while simultaneously reducing the proportion of <250 μm aggregates. Compared with ORC, both ORNS and ORN increased the proportion of >250 μm aggregates by 19.0 %–35.6 % and 14.0 %–28.0 %, respectively, while decreasing the proportion of <250 μm aggregates by 23.8 %–45.7 % and 17.1 %–32.2 %. Moreover, long-term conservation tillage had a significant impact on SOC fractions content, soil enzyme activities and total phospholipid fatty acid (PLFA) of both >250 μm and < 250 μm aggregates. In both >250 μm and < 250 μm aggregates, compared with ORC, ORNS and ORN resulted in higher the SOC fractions content (dissolved organic C, microbial biomass C, light fraction organic C, and particular organic C) by 6.2 %–113.5 % and 4.2 %–71.2 %, the enzyme activities (cellobiohydrolase, β-glucosidase, xylosidase and polyphenol oxidase) by 10.2 %–74.5 % and 9.0 %–77.3 %, the PLFA by 14.6 %–37.2 % and 9.0 %–28.5 %, respectively. Partial Least Squares Path Modeling further indicated that long-term conservation tillage mainly affected the SOC by meditating microbial community in >250 μm aggregates, and by changing microbial community and organic C fractions in <250 μm aggregates. Overall, long-term conservation tillage serves as an effective management strategy for the accumulation of SOC in rice-oilseed rape rotation systems. This approach holds significant importance for mitigating climate change and ensuring food security.
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2. 题目: Anammox-induced magnesium phosphate mineralization for digestate treatment: Organic matter intervention and elemental flow

文章编号: N24122406
期刊: Chemical Engineering Journal
作者: Jiayi Li, Yu Zhang, Yongxing Chen, Yonggan Li, Junfeng Yang, Wenlu Li, Yuzhu Yan, Xiaojun Wang
更新时间: 2024-12-24
摘要: Anaerobic ammonium oxidation (anammox)-induced high added value magnesium phosphate (MP) mineralization represents a significant innovation for the simultaneous nitrogen removal and phosphorus recovery from wastewater. However, understanding the robustness and phosphorus removal in treating complex actual wastewater remains limited. In this study, a partial nitrification (PN)/anammox coupling MP mineralization (AMX-MP) process was established to treat actual digestate, achieving nitrogen and phosphorus removal efficiencies of 91.5 % and 81.6 %, respectively. Contrary to the thermodynamic calculations, experimental results indicated that dissolved organic matter (DOM) was a key factor negatively affecting the MP mineralization in AMX-MP system. However, the presence of DOM tended to promoted slow nucleation and fast crystals growth, resulting in larger crystal formation. Furthermore, the flow of inorganic elements within the system improved the settling performance of sludge, particularly for granular sludge formed by the coupling of MP and anammox consortia, promoting the retention of functional microorganism. The establishment of the AMX-MP system likely enhanced the abundance of functional genes and electron flow, supporting anammox-dominated nitrogen removal. Our findings provide underlying insights into the treatment of real high-strength wastewater using PN/AMX-MP process.
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3. 题目: Quantitatively tracing the decomposition of endogenous particulate organic carbon during sinking in (sub-)deep reservoirs: Using radiocarbon isotopes Δ14C

文章编号: N24122405
期刊: Water Research
作者: Chao Yin, Yan Zeng, Jingan Chen, Guangrong Ran, Haiquan Yang, Jia Yu, Jingfu Wang, Ziyan Zhang, Xudong Guo
更新时间: 2024-12-24
摘要: The rapid expansion of reservoirs, coupled with increasing eutrophication, has profoundly influenced regional and global carbon cycles. To precisely assess the carbon sink potential of reservoirs, it is crucial to quantify the decomposition of endogenous particulate organic carbon (POC) during the deposition and sinking of particulate matter in reservoirs. This is particularly important in the context of rising temperatures and intensified human activities. In this study, the Hongfeng Reservoir, an artificial reservoir in a karst basin on the Yunnan-Guizhou Plateau in China, was selected as a representative reservoir to systematically explore the sources and evolution of endogenous POC in (sub-)deep reservoirs. Particulate matter and water samples were collected from inflowing rivers and reservoir water profiles to analyze the content of POC, stable isotope of POC (δ¹³CPOC), radioisotope of POC (Δ¹⁴CPOC), particulate nitrogen, and chlorophyll concentrations. The results revealed significant differences in POC content and carbon isotope signatures between riverine and reservoir particulate matter, primarily due to distinct POC sources. Riverine particulate matter exhibited C/N ratios of 10.4 to 18.4, δ¹³CPOC values of -29.3 ‰ to -26.1 ‰, and Δ¹⁴CPOC values of -282 ‰ to -183 ‰, in contrast, particulate matter in the reservoir's surface water had C/N ratios of 5.1 to 6.9, δ¹³CPOC values of -34.6 ‰ to -31.3 ‰, and Δ¹⁴CPOC values of -162 ‰ to -143 ‰. From the surface to the bottom of the reservoir water profile, the C/N ratio of particulate matter gradually increased, Δ¹⁴CPOC became increasingly negative, and δ¹³CPOC exhibited varying trends across different water profiles. The combined analysis of chlorophyll and other variables demonstrated that Δ¹⁴CPOC is the most reliable indicator for tracing the source and decomposition process of POC during particulate matter sinking in the reservoir. Quantitative estimates based on Δ¹⁴CPOC indicated that the contribution of endogenous POC decreased from 73–85 % in the surface water to 41–57 % in the bottom water, with 74.7–75.4 % of endogenous POC decomposed during the sinking process, suggesting that only a small fraction of endogenous organic matter could reach the reservoir bottom and was ultimately buried in sediments. Future research should focus on quantifying the fate of endogenous organic matter decomposition products to enhance understanding of reservoirs’ carbon sink potential.
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4. 题目: Influence of iron-modified biochar on phosphate transport and deposition in saturated porous media under varying pH, ionic strength, and biochar dosage

文章编号: N24122404
期刊: Chemosphere
作者: Rakesh Kumar, Jasmeet Lamba, Sushil Adhikari, Nitesh Kasera, Henry Allen Torbert
更新时间: 2024-12-24
摘要: Phosphorus (P) is one of the essential nutrients required for plants; however, loss of phosphorus from agricultural areas results in water quality impairment. This research aims to investigate the transport and deposition of phosphate at different solution chemistries and phosphate-biochar dosages under (a) individual phosphate flow, (b) phosphate transport followed by biochar, and (c) co-transport of biochar-phosphate in saturated porous media. Breakthrough curves (BTCs) for phosphate were generated to understand the effect of pine raw biochar (BC) and iron-modified biochar (Fe-BC) on phosphate transport and deposition under varying solutions, pH (5.5 ± 0.1–10.5 ± 0.1), ionic strength (0–10 mM), phosphate (10–20 mg/L), and biochar dosages (100–200 mg/L) in saturated porous media. Results revealed increased deposition of BC and Fe-BC at high ionic strength (IS), i.e., 10 mM compared to 0 mM. The BTCs of phosphate (10–20 mg/L) transport at increasing IS showed delayed elute and long tailing curves compared to BTCs of tracer. Further, phosphate transport using BTCs in biochar-mediated saturated porous media was investigated at 10–20 mg/L phosphate, where maximum retardation (37%) was observed at pH 6.7 ± 0.1 and 0 mM IS due to the availability of active sites for 10 mg/L phosphate using Fe-BC than BC. The BTCs of phosphate transport at pH 6.7 ± 0.1 and 0–10 mM IS showed 37% and 40% phosphate deposition in Fe-BC-mediated columns for 0 mM and 10 mM, respectively, than BC-mediated columns. For BC, maximum phosphate adsorption was observed at pH 5.5 ± 0.1, whereas for Fe-BC, it was observed at pH 6.7 ± 0.1 at 10 mM IS. The least adsorption was observed at pH of 10.5 ± 0.1 for both BC and Fe-BC. Similar phosphate retardation BTCs for BC and Fe-BC at 10 mM were observed with adsorption of 40% phosphate for 100–200 mg/L biochar dosages. Besides, co-transport and deposition of biochar and phosphate, considering with and without ripening effect, reported high phosphate retardation using Fe-BC than BC at pH of 6.7 ± 0.1 and 10 mM IS due to chemical non-equilibrium and mass transfer. Taken together, iron-modified biochar (Fe-BC) showed significant adsorptive potential for phosphate management in saturated porous media. Overall, modeling of transport and deposition of phosphate and biochar are significant to understanding fate, nutrient mobility & management, biochar-phosphate interactions, and remediation designs in saturated porous media.
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5. 题目: Molecular-Level Insights into Recalcitrant Ozonation Products from Effluent Organic Matter

文章编号: N24122403
期刊: Environmental Science & Technology
作者: Elaine K Jennings, Millaray Sierra Olea, Uwe Hübner, Rebecca Rodrigues Matos, Thorsten Reemtsma, Oliver J Lechtenfeld
更新时间: 2024-12-24
摘要: Wastewater ozonation is commonly employed to enhance the subsequent biodegradation of effluent organic matter (EfOM) and contaminants of concern. However, there is evidence suggesting the formation of recalcitrant ozonation products (OPs) from EfOM. To investigate the biodegradability of OPs we conducted batch biodegradation experiments using wastewater effluent ozonated with mass-labeled (¹⁸O) ozone. Molecular level analysis of EfOM was performed using reversed-phase liquid chromatography coupled with Fourier transform ion cyclotron resonance mass spectrometry (LC-FT-ICR MS) after 3 and 28 days in batch bioreactors. The use of mass labeling allowed for the unambiguous detection of OPs, with 2933 labeled OP features identified in the ozonated EfOM. Furthermore, employing polarity separation with LC facilitated the investigation of reactivity among different OP isomers. Overall, OPs exhibited a comparable proportion of recalcitrant and bioproduced molecular formulas when compared to the remaining EfOM, with 12% of OPs classified as recalcitrant and 17% bioproduced, indicating that OPs themselves are not inherently biodegradable. Additionally, recalcitrant OPs were found to be more polar based on the O/C ratios and retention time, in comparison to biodegradable OPs. Approximately one-third of the OP isomers displayed variations in their biodegradability, suggesting that studying the degradability of ozonated EfOM at the molecular formula level is heavily influenced by structural differences. Here, we offer unique insight into the biological transformation of EfOM after ozonation using labeled ozone and LC-FT-ICR MS analysis.
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6. 题目: Potential of biochar to mitigate methane production in paddy soils—application of a new incubation and modelling approach

文章编号: N24122402
期刊: Biogeochemistry
作者: Thomas Middelanis, Dana Looschelders, Peter Mueller, Klaus-Holger Knorr
更新时间: 2024-12-24
摘要:

Paddy soils are a significant source of methane (CH₄) affecting the global climate. Therefore, it is important to investigate both emission mitigation strategies and the underlying biogeochemical processes. The application of biochar into paddy soils has emerged as a promising measure to mitigate CH₄ emissions. However, it has not yet been clarified why such effects are usually weaker in field studies than in laboratory incubations and which properties of biochar specifically decrease the production of CH₄. We conducted two incubation experiments, one with 1.5% addition of untreated biochars and one with same amounts, but pH-levelled, rinsed biochars. According to the common experimental design of existing incubation studies (experiment 1) biochar addition induced a mean soil pH increase of 0.28 after anaerobic incubation compared to the contro. In these treatments, biochar significantly extended the pre-methanogenic stage (mean 24.23%). However, this effect was weakened or even reversed when pH-levelled, rinsed biochars were amended in experiment 2, which was intended to mimic the persistent long-term effects in the field. This indicated that the provision of electron accepting capacities to suppress methanogenesis may be less important than previously thought. The addition of biochar significantly lowered CH₄ production rates m in both experiments with no significant influence of the pH (mean 25.89%), though. Our study demonstrated that incubation studies on CH₄ production in paddy soils can be improved by separating the pre-methanogenic and the methanogenic stage. This facilitates future research to compare characteristics of biochar, but also combinations of measures to optimise CH₄ mitigation strategies.

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7. 题目: Iron-reducing bacteria bioremediation for organic contaminated urban river sediment enhanced by chemical regulation: Strategy, effect and mechanism

文章编号: N24122401
期刊: Journal of Environmental Chemical Engineering
作者: Ketong Li, Bin Wang, Suyun Chang, Jianjun Huang, Jingmei Sun
更新时间: 2024-12-24
摘要: Organic-rich sediments are a major cause of the black and odorous rebound of water bodies. The combination of chemical regulation and bioremediation can effectively stimulate the bioremediation process and enhance the in-situ remediation of organic contamination in river sediments. In this study, a bioremediation approach under chemical regulation was constructed to achieve the sustainable degradation of organic matter in the sediments. The sediment bioremediation strategy consisted of three stages: first, using Ca(NO₃)₂-CaO₂ to improve the microecological environment of the sediment; second, promoting the biodegradation of organic matter through iron-reducing bacteria (IRB); and finally, employing CaO₂ to enhance the bioremediation process further. The results indicated that, in Stage I, Ca(NO₃)₂-CaO₂ oxidized acid-volatile sulfides (AVS) and ferrous iron in the sediments, effectively improving the redox conditions and inhibiting the sulfate respiration and methanogenic metabolism of microorganisms. Furthermore, Ca(NO₃)₂-CaO₂ stimulated microorganisms in the sediments to secrete polyphenol oxidase and FDA hydrolytic enzymes, facilitating the transformation of recalcitrant organic matter and improving its biodegradability. In Stage II, iron-reducing bacteria (IRB) mediated the reduction of recalcitrant organic matter hindered by steric hindrance effects through extracellular respiration, driving the efficient degradation of total organic matter (TOM) in the sediments. In Stage III, the addition of CaO₂ accelerated the Fe(II)/Fe(III) redox cycle and further promoted the degradation of TOM by IRB, achieving a maximum degradation rate of 29.95%. This study demonstrated the feasibility of the three-stage remediation strategy of Ca(NO₃)₂-CaO₂ and IRB and its mechanisms, providing valuable insights for further research on the integrated remediation of organic contaminated sediment.
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