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261. 题目: Global crop production increase by soil organic carbon
文章编号: N23110202
期刊: Nature Geoscience
作者: Yuqing Ma, Dominic Woolf, Mingsheng Fan, Lei Qiao, Rong Li, Johannes Lehmann
更新时间: 2023-11-02
摘要:
Soil organic carbon sequestration has been promoted to combat climate change while improving soil fertility. However, its quantitative contribution to crop productivity has proven elusive. Using data from 13,662 controlled field trials with 66,593 treatments across a broad range of soils, climates and management practices, we here show that yields increase with increased soil organic carbon, until no further increase (p < 0.05) occurs above mean optimum soil organic carbon of 43.2–43.9 g kg−1 for maize, 12.7–13.4 g kg−1 for wheat and 31.2–32.4 g kg−1 for rice. Sequestering soil organic carbon is one-fifth as effective (that is, 80% less) as nitrogen fertilization for improving crop yield where soil management is optimized. By increasing soil organic carbon beyond current technology to optimum levels, global production of the three most important staple crops increases by 4.3% (sufficient to provide calories for 640 million people). However, currently available management practices would increase crop production by only 0.7% once other production constraints have already been addressed. Therefore, yield improvements under currently available technologies are unlikely to drive adoption of soil organic carbon sequestration globally, except in hot-spot regions where crop production benefits most, or unless novel practices that allow greater soil organic carbon sequestration beyond current limitations can further increase yields cost-effectively.
262. 题目: Sludge-derived biochar applied in peroxymonosulfate (PMS) activation: Reactive oxygen species (ROS) dominated process and characteristics
文章编号: N23110201
期刊: Journal of Environmental Chemical Engineering
作者: Yizhou Feng, Meiyu Liu, Qiyu Shi, Yunan Song, Luni Yang, Jianfeng Zhang, Zhihua Li, Weihuang Zhu
更新时间: 2023-11-02
摘要:
Herein, sludge-derived biochar (BS) as an effective peroxymonosulfate (PMS) activator (BS900) was prepared by a simple one-step pyrolysis treatment. The BS900 demonstrated remarkable capability in activating PMS for efficient tetracycline (TC) removal. The existence of zero-valent iron (Fe0), the elevated ratio of Fe2+ to Fe3+, and the elevated percentage content of graphitic N were identified as the main contributors to the high PMS activation performance of BS900. Correspondingly, compared with other BS-derived PMS activators, the lowest charge transfer resistance (Rct) of BS900 was obtained, indicating efficient charge transfer between the PMS molecule and BS900. The generated reactive oxygen species (ROS) including the superoxide radical (O2•-) and singlet oxygen (1O2) were verified by the radical trapping and electron paramagnetic resonance (EPR) tests during the BS-induced PMS activation process. The generated O2•- served as the precursor for 1O2 formation. Whereas, the yields of the OH• and SO4•- were inhibited, suggesting that PMS activation by BS900 was a process dominated by ROS. Furthermore, the evaluation of ecotoxicity showed the TC degradation intermediates exhibit lower developmental toxicity and no mutagenicity. The research offers a novel perspective into the characteristics and mechanism of PMS-based advanced oxidation processes (AOPs) catalyzed by sludge-derived biochar.
263. 题目: Influence of mineralized organic carbon in marine sediments on ecological heavy metal risk: Bohai Bay case study
文章编号: N23110112
期刊: Environmental Research
作者: Congxiao Li, Yan Zhang, Rui Chen, Nayu Wang, Jingjing Liu, Fude Liu
更新时间: 2023-11-01
摘要:
The organic matter in sediments can mineralize over time, which impacts the morphology of the heavy metals therein, which in turn affects the assessment of the risks posed by heavy metals. We used the sediments of Bohai Bay as the study object and analyzed the effects of different organic carbon mineralization levels on the concentrations of heavy metals (Cr, Pb, Cu, Zn, and Cd) using water extraction and potassium permanganate oxidation. The mean concentrations of Cd, Pb, Cu, and Zn in Bohai Bay were within the limits recommended by the World Health Organization. The proportions of the active and inert organic carbon fractions were 61.72% and 32.94%, respectively. Organic carbon mineralization most strongly impacted Cd and Pb levels, with releases accounting for 47.92% and 25.75%, respectively, of the oxidizable fractions. The release of all heavy metals, except for Cr, increased with increases in organic carbon mineralization, and heavy metals were released at a maximum rate of 12.94% when the organic carbon was highly mineralized, whereas Cr was released at a maximum of 0.023% during the first stage of organic carbon mineralization. In terms of spatial distribution, the concentration of mineralizable organic carbon in the sediments of the estuaries was substantially higher than that in other marine areas. Estuary sediments were more easily affected by organic carbon mineralization; therefore, the heavy metals in the oxidizable fraction of the estuarine region were more easily transformed into unstable heavy metal forms, posing high risk levels. Therefore, this study highlights the effects of organic carbon mineralization on heavy metal morphology and stability, when evaluating the ecological risk of heavy metals in marine sediments.
264. 题目: Digging deeper: Assessing the predictive power of common greenhouse gas accounting tools for soil carbon sequestration under organic amendment
文章编号: N23110111
期刊: Journal of Cleaner Production
作者: K R Ball, I C Burke, D P Collins, C E Kruger, G G Yorgey
更新时间: 2023-11-01
摘要:
Effective project implementation and quantification of emissions reduction in climate-smart agriculture initiatives face challenges in measurement, monitoring, and verification. To address these challenges, predictive models are regularly used to estimate the emissions reduction potential of land management changes and to prioritize funding for projects. Despite their growing utility, few studies have evaluated the performance of publicly available model tools using site specific data. This study evaluated the performance and utility of four common model tools that represent the three Intergovernmental Panel on Climate Change model tiers to predict soil organic carbon storage and estimate greenhouse gas emissions on working lands under organic matter amendment. Field data from two long-term, compost application experiments in Washington State formed the basis for model simulations using DayCent, COMET-Farm, Cool Farm, and the Washington State Climate Smart Estimator (WaCSE). Soil carbon sequestration and emissions estimates varied among the evaluated models, which was expected given their differential data requirements and input capabilities. COMET-Farm, although easier to use, exhibited a higher level of bias compared to DayCent, which was expected as a mixed tier model. The DayCent model, the model engine for the COMET-Farm tool, demonstrated the ability to explain ∼50% more of the variation in the observed values compared to COMET-Farm when initiated using the same parameters. Cool Farm was unsuitable for estimating SOC sequestration benefits from compost application primarily because it did not add carbon to the soil pool following amendment. The differences in emissions estimates derived from WaCSE compared with other tools could be attributed solely to its highly constrained input parameters and basis in tier 1 emissions factors. We conclude that online tools can provide rapid estimates of greenhouse gas emissions reduction potential over larger areas or groups of farms but should be used with caution for site-specific estimates. Hence, it is crucial to clarify the intended purpose of an assessment and the designed function of model tools when evaluating their suitability for prioritizing funding for climate-smart agriculture initiatives at the individual farm level.
265. 题目: Long-term conversion of upland to paddy increased SOC content and N availability in a sand dune of Japan
文章编号: N23110110
期刊: Catena
作者: Intan Lusiana Dewi, Shuirong Tang, Margi Asih Maimunah, Eric Cantona, Jean Yves Dukuzumuremyi, Christian Nkurunziza, Sri Nuryani Hidayah Utami, Eko Hanudin, Satoshi Hattori, Keitaro Tawaraya, Weiguo Cheng
更新时间: 2023-11-01
摘要:
Land use change driven by anthropogenic activities has greatly affected terrestrial C and N cycling; however, it remains unclear how dynamics of soil organic carbon (SOC) and nitrogen (N) availability respond to long-term land use change in sand dunes. Here, we investigated the changes in SOC, total nitrogen (TN), and their aerobic and anaerobic decomposition or mineralization in a vinyl film paddy, compared with dry land use and management changes (LUMCs) (original upland, greenhouse, and agricultural forest (tree area)) in Shonai sand dunes, northeast Japan. The vinyl film paddy had been singly cultivated for 54 years. Soil samples were collected from five soil depths (0–10, 10–20, 20–30, 30–40, 40–50 cm) to compare the effects of depth and LUMC among the four treatments. The C decomposition (Dec-C) was assessed as the aerobic CO2 production and anaerobic methane and CO2 productions. Meanwhile, N mineralization (Min-N) was determined as aerobic NH4+ and NO3– production and anaerobic NH4+ production. The results showed that the vinyl film paddy increased SOC and TN contents, Dec-C and Min-N than upland and greenhouses at 0–30 cm depth but lower levels than the tree area at all depths. The arithmetic mean for all depths showed the aerobic Dec-C in the paddy (216.0 mg kg−1) was higher than the corresponding anaerobic Dec-C (192.8 mg kg−1). Conversely, the aerobic Min-N (35.9 mg kg−1) was lower than the anaerobic Min-N (75.7 mg kg−1). There were significantly positive correlations among SOC, TN, aerobic and anaerobic Dec-C and Min-N, whereas the paddy had steeper slope than other three LUMCs. Conclusively, our results indicated that long-term conversion of upland to vinyl film paddy increased SOC and TN accumulation and N availability (Min-N) in Shonai sand dunes, which can be applied as an effective agricultural practice to improve fertility of coastal sandy soils.
266. 题目: Small Reservoirs as Nitrogen Transformers: Accounting for Seasonal Variability in Inorganic and Organic Nitrogen Processing
文章编号: N23110109
期刊: Journal of Geophysical Research: Biogeosciences
作者: Christopher T Whitney, Wilfred M Wollheim, Arthur J Gold, Joshua M Buonpane
更新时间: 2023-11-01
摘要: Anthropogenic nitrogen (N) inputs to the landscape have serious consequences for inland and coastal waters. Reservoirs are effective at mitigating downstream N fluxes but measurements have generally focused on large reservoirs and have not considered seasonal variability or all N forms. In this study, we conducted an N mass balance in eight small reservoirs (surface area <0.55 km2) in coastal New England over annual time periods, including both inorganic and organic forms of N. We found that small reservoirs have high capacity for dissolved inorganic N (DIN) retention during low and moderate discharge, but are roughly in balance for DIN at higher discharge. Because proportional DIN retention occurred when N inputs were at their lowest, their effect on downstream N fluxes is small over annual time frames. Further, dissolved organic N (DON) was also evident during low flow late in the warm season. Accounting for DON production, the net effect of reservoirs on total dissolved N (TDN) fluxes was limited. These transformations between inorganic and organic N should be considered when evaluating the effect of small reservoirs on TDN fluxes over seasonal and annual timescales. With dam removal becoming a common solution to aging, unsafe dams, their ability to retain or produce N must be scrutinized at longer time scales while accounting for the complete N pool to better comprehend the effect their reservoirs have on downstream waters.
267. 题目: High-efficient removal and adsorption mechanism of organic dyes in wastewater by KOH-activated biochar from phenol-formaldehyde resin modified wood
文章编号: N23110108
期刊: Separation and Purification Technology
作者: Zhenxin Zhang, Mingchang Zhang, Xiaoqi Zhao, Jinzhen Cao
更新时间: 2023-11-01
摘要:
The treatment of wastewater contaminated with organic dyes has become an intricate challenge in water pollution control. Currently, sophisticated chemical modifications and synthetic methods are frequently needed to enhance the adsorption capacity of biochar for removing dyes during the treatment process. In order to develop a facile, low-cost and efficient biochar absorbent, an activated biochar (KOH/PF-WB) was successfully synthesized from phenol-formaldehyde (PF) resin modified wood via pyrolysis and potassium hydroxide (KOH) activation. Based on the joint effect of PF resin and wood, KOH/PF-WB-700–2 exhibited a remarkable porous structure and abundant oxygen-containing functional groups, which resulted in a substantially high specific surface area (SBET = 2301.61 m2/g) and total pore volume (Vtotal = 1.205 cm3/g). Additionally, the PF resin modification led to increased disorder and more defect sites of activated wood biochar. As a result, KOH/PF-WB-700–2 demonstrated superior adsorption capacity for congo red (3472.22 mg/g) and methylene blue (1112.35 mg/g) dyes compared to some reported adsorbents. The adsorption process could be better described by the pseudo-second-order kinetic model and Langmuir isotherm model, while the overall process was spontaneous and feasible. The primary adsorption mechanism involved pore filling through the modulation of PF resin, along with the cooperative effects of electrostatic attraction, hydrogen bonding and π-π interaction. This finding provides a viable strategy for the waste PF-modified wood cyclic application, and offer technical support for the prospect of KOH/PF-WB for the removal of organic dyes.
268. 题目: Characteristics of microplastic-derived dissolved organic matter and its binding with pharmaceuticals unveiled by fluorescence spectroscopy and two-dimensional correlation spectroscopy
文章编号: N23110107
期刊: Science of the Total Environment
作者: Caixia Yan, Xiao Wang, Minghua Nie, Xiting Mo, Mingjun Ding, Jie Chen, Yi Yang
更新时间: 2023-11-01
摘要:
Microplastics were an extensively detected pollutant in the environment, but microplastic-derived dissolved organic matter (MP-DOM) has received less attention, much less its impact on the binding behavior of pollutants (e.g., pharmaceuticals). In this study, DOM derived from two typical MPs, i.e., polyethylene terephthalate (PET) and polystyrene (PS) was generated by UV irradiation (a widely used way for MPs' aging treatment) and characterized by multiple spectroscopic techniques and methods. Chloramphenicol (CAP) and carbamazepine (CBZ) were selected to investigate the binding mechanism between MP-DOM and pharmaceuticals. After UV irradiation, the concentration of the dissolved organic carbon, colored DOM, and carboxyl/carbonyl groups of MP-DOM increased. Moreover, the humic-like substance released preceding and more under UV irradiation. Furthermore, the protein-like substances on PET-DOM and the humic-like substances on PS-DOM were positively correlated to the binding capacity to the pharmaceuticals, respectively. 2D-COS results revealed that the fluorescent materials having more oxygen-containing functional groups for MP-DOM preferentially interacted with the pharmaceuticals. Overall, the higher fluorescence quenching was related to the protein-like substance, CBZ, and PET-DOM as compared to the humic-like substance, CAP, and PS-DOM. It was verified by the relatively high binding ability (logKM) for them (the protein-like substance: 5.15; CBZ: 4.61; PET: 4.48). This study first proved the environmental reactivity of MP-DOM to the pharmaceuticals highlighting the significance of the spectral properties for the binding behavior of MP-DOM with pharmaceuticals and the competitive sorption role of MP-DOM to the pollutants in the natural environment.
269. 题目: Impacts of lignite and biochar addition on anaerobic digestion of and fertilizer production from dairy manure
文章编号: N23110106
期刊: Bioresource Technology
作者: Anna Leithaeuser, Roland Span, Mandy Gerber
更新时间: 2023-11-01
摘要:
Anaerobic digestion (AD) is one of the most popular technologies to convert organic residues into renewable energy. The use of additives has been shown to increase the process stability and degradation efficiency during AD. However, little attention has been paid to the associated fertilizer production. Thus, this study aims to simultaneously investigate the impact of biochar and lignite on AD and fertilizer production of dairy manure in semi-continuous experiments. Results show that compared to the biogas production rate (BPR) of the reference (394.01±0.39 lN/(kgVS∙d), lignite can increase BPR by 4.98%, whereas no impact on BPR was detected due to biochar addition. This indicates that higher O/C and H/C ratios attributed to lignite are a dominant factor influencing BPR, while high specific surface area is not beneficial. Nitrogen yield in the solid phase was increased by 19.47% (lignite) and 14.65% (biochar), significantly promoting the utilization of digestate as solid nitrogen fertilizer.
270. 题目: Unexpected high alkyl carbon contents in organic matter-rich sandy agricultural soils of Northwest Central Europe
文章编号: N23110105
期刊: Geoderma
作者: Livia Urbanski, Karsten Kalbitz, Janet Rethemeyer, Peter Schad, Ingrid Kögel-Knabner
更新时间: 2023-11-01
摘要:
Carbon sequestration in Plaggic Anthrosols is most often investigated by bulk soil carbon inventories, without considering the form in which the carbon is stored (e.g., particulate or mineral-associated organic matter (OM), its capacity, or its chemical composition). Here, we focus on the unusual high organic carbon (OC) accumulation in sandy Plaggic Anthrosols and adjacent reference soils under agricultural use. In these soils, the mineral fraction ≤20 µm which is commonly assumed to be the major factor for OC stabilization, are very low in mass proportion. Soil organic matter (SOM) physical fractionation was done to evaluate the quantity and quality of OC in the topsoil (Ap horizon). For the fraction ≤20 µm (medium and fine silt-, and clay-sized particles), we measured the concentration of OC and calculated its OC storage capacity and contribution. The OC of the fraction ≤20 µm was radiocarbon-dated and analyzed for its chemical composition by solid-state 13C NMR spectroscopy. The highly sandy (∼90 % sand and coarse silt) soils showed an accumulation of OC much higher than the conventionally calculated saturation level controlled by the proportion of the fraction ≤20 µm. Unexpectedly, Plaggic Anthrosols and the respective reference soils showed similar fractional OC concentrations, radiocarbon ages, and OM composition. The isolated fraction ≤20 µm contained, on average, 81 % of the total soil OC in only 9 % of the corresponding soil mass. All soil fractions ≤20 µm are characterized by a high mean OC concentration in the topsoil (reference soils: 226 ± 66.5 mg OC g−1, Plaggic Anthrosols: 202 ± 59.0 mg OC g−1) with a C/N ratio of 15 on average for both soils. The OM composition of the fraction ≤20 µm was specifically rich in alkyl-C, with unusually low proportions of O-alkyl-C and low contents of aryl-C. The radiocarbon concentration (F14C) indicated that topsoil OM of the ≤20 µm fraction is stored for long time periods with high mean conventional radiocarbon ages (14C) not only for Plaggic Anthrosols (F14C: 0.92 ± 0.04; 14C: 639 yBP) but also for the reference soils (F14C: 0.93 ± 0.04; 14C: 575 yBP) and received low inputs of OC derived from recent photosynthesis. Our data indicate the existence of specific SOM accumulation processes in the investigated sandy agricultural soils, resulting particularly large SOM stocks which cannot be explained by mechanistic association of OM with mineral surfaces. It is not clear, if this inherited OM is stable under present-day soil and management conditions.
271. 题目: Pretreatment of marine sediment for the removal of di-(2-ethylhexyl) phthalate by sulfite in the presence of sorghum distillery residue-derived biochar and its effect on microbiota response
文章编号: N23110104
期刊: Chemosphere
作者: Chang-Mao Hung, Chiu-Wen Chen, Chin-Pao Huang, Cheng-Di Dong
更新时间: 2023-11-01
摘要:
This study investigates the mechanism behind the oxidation di-(2-ethylhexyl) phthalate (DEHP) in marine sediment by coupling sulfite using biochar prepared from sorghum distillery residue (SDRBC). The rationale for this investigation stems from the need to seek effective methods for DEHP-laden marine sediment remediation. The aim is to assess the feasibility of sulfite-based advanced oxidation processes for treating hazardous materials such as DEHP containing sediment. To this end, the sediment in question was treated with 2.5 × 10−5 M of sulfite and 1.7 g L−1 of SDRBC700 at acidic pH. Additionally, the study demonstrated that the combination of SDRBC/sulfite with a bacterial system enhances DEHP removal. Thermostilla bacteria were enriched, highlighting their role in sediment treatment. This study concludes that sulfite-associated sulfate radicals-driven carbon advanced oxidation process (SR-CAOP) offers sustainable sediment pretreatment through the SDRBC/sulfite-mediated microbial consortium, in which the SO3•− and 1O2 were responsible for DEHP degradation. SDRBC/sulfite offers an effective and environmentally friendly method for removing DEHP. Further, these results can be targeted at addressing industry problems related to sediment treatment.
272. 题目: The effect of bulk-biochar and nano-biochar amendment on the removal of antibiotic resistance genes in microplastic contaminated soil
文章编号: N23110103
期刊: Environmental Research
作者: Xiangmiao Su, Fanghan Qian, Yanyu Bao
更新时间: 2023-11-01
摘要:
Biochar amendment has significant benefits in removing antibiotic resistance genes (ARGs) in the soil. Nevertheless, there is little information on ARGs removal in microplastic contaminated soil. Herein, a 42-day soil microcosm experiment were carried out to study how two coconut shell biochars (bulk- and nano-size) eliminate soil ARGs with/without microplastic presence. The results showed that microplastic increased significantly the numbers and abundances of ARGs in soil at 14d of cultivation. And, two biochars amendment effectively inhibited soil ARGs spread whether or not microplastic was present, especially for nano-biochar which had more effective removal compared to bulk-biochar. However, microplastic weakened soil ARGs removal after applying same biochar. Two biochars removed ARGs through decreasing horizontal gene transfer (HGT) of ARGs, potential host-bacteria abundances, some bacteria crowding the eco-niche of hosts and promoting soil properties. The adverse effect of microplastic on ARGs removal was mainly caused by weakening mobile genetic elements (MGEs) removal, and by changing soil properties. Structural equation modeling (SEM) analysis indicated that biochar's effect on ARGs profile was changed by its size and microplastic presence through altering MGEs abundances. These results highlight that biochar amendment is still an effective method for ARGs removal in microplastic contaminated soil.
273. 题目: Promotion of phosphate release from humic acid-iron hydroxide coprecipitates in the presence of citric acid
文章编号: N23110102
期刊: Environmental Research
作者: M M M Ahmed, Kai-Yue Chen, Fang-Yu Tsao, Yi-Cheng Hsieh, Yu-Ting Liu, Yu-Min Tzou
更新时间: 2023-11-01
摘要:
Phosphate (P) resources are expected to be depleted within a century. Therefore, promoting balanced phosphorus fertilizer use and understanding phosphorus dynamics in soils containing iron (III), organic acids, and iron (III)-organic molecule particulates is crucial. This study investigated the sorption of citric acid onto humic acid-iron hydr(o)xide coprecipitate (HAFHCP) and the reciprocal effects of citric acid and phosphorus sorption on HAFHCP with different carbon-to-iron (C/Fe) ratios. The results showed that the maximum sorption capacity (MSC) of citric acid on HAFHCP decreased with increasing C/Fe ratios in the HAFHCP. The P sorption on HAFHCP pre-sorbed with citric acids (denoted as C–P) decreased by 50% compared with that of the MSC on FH. However, citric acids could only reduce P sorption by 20% when P was pre-sorbed on HAFHCP (denoted as P–C). The results suggested that upon the formation of HAFHCP, citric acids might increase P availability, particularly in the C–P system. Although citric acids would initially inhibit P sorption on HAFHCP in the P–C system, P sorption increased with a prolonged reaction time. The exposures of new sorption sites upon dissolution of Fe from HAFHCP by citric acids or/and the formations of Fe bridge between P and organic domains of HAFHCP might contribute to the results. Besides, a number of large HAFHCP aggregates became smaller while sorbing P due to the increasing electric repulse on the surfaces of FH of HAFHCP, enabling the subsequent dissolutions of more Fe by citric acids from HAFHCP in the P–C system. By integrating these innovative and sustainable strategies, the recycling and reuse of P can be optimized, thereby minimizing the reliance on synthetic fertilizers and mitigating environmental impacts. This approach fosters the efficient utilization of phosphorus resources, improves soil fertility, and enhances the overall resilience of agricultural systems and ecosystems.
274. 题目: Soil moisture and bacterial carbon limitation regulate the soil organic carbon in mountain peatlands
文章编号: N23110101
期刊: Catena
作者: Zhiwei Xu, Yuting Wang, Hongkai Li, Yanmin Dong, Zucheng Wang, Ziping Liu, Shasha Liu, Dejing Sun, Hongyan Zhao, Shengzhong Wang
更新时间: 2023-11-01
摘要:
Peatlands are crucial carbon (C) sinks, and the combined activities of soil bacteria and soil abiotic properties play an essential role in regulating the C cycle. However, mountain peatlands are particularly vulnerable to global change, which could lead to a change from C sink to source. Understanding how variations in soil bacterial communities and diversity along an altitude gradient affect C storage through changes in enzyme stoichiometry ratios is essential. To address this issue, this study collected soil samples from six peatlands at different altitudes in the Changbai Mountains, China, which were dominated by either sedge or shrub/Sphagnum species. The study examined a range of soil physical and chemical properties, quantified bacterial community diversity and structure, and assessed enzyme stoichiometry. The results indicated that bacterial communities varied with altitude and vegetation, with bacterial α-diversity (richness) being higher at lower altitudes and in sedge-dominated peatlands. Mean annual air temperature (MAAT) and mean annual precipitation (MAP) were the primary drivers of bacterial diversity, and soil bacterial community composition was significantly influenced by soil carbon/phosphorus (C/P) ratio and MAP. On the other hand, soil pH had only minor effected in mountain peatlands. Path analysis emphasized the greater importance of soil moisture and microbial C limitations than bacterial richness and community on soil organic carbon (SOC) in mountain peatlands. The study also suggested that increasing bacterial richness and relative abundances of rare phyla could increase soil C concentration in peatlands. Overall, this study provided valuable insights into the regulation of C cycling in mountain peatlands and could help mitigate global climate change.
275. 题目: Performance and mechanism of glycerol-driven denitrifying phosphorus removal from low organic matter sewage
文章编号: N23103112
期刊: Bioresource Technology
作者: Guanglin Zhang, Weiguang Li, Shuncai Wang, Donghui Li, Duoying Zhang, Longyi Lv
更新时间: 2023-10-31
摘要:
The performance and mechanism of the glycerol-driven denitrifying phosphorus removal (DPR) process were investigated in low organic matter wastewater treatment using the modified anaerobic-anoxic–oxic (MAAO) system. The results revealed that denitrifying bacteria preferentially utilized glycerol, reducing nitrate interference on anaerobic phosphate release. Fermentation bacteria converted excess glycerol into available carbon sources, which were utilized by denitrifying phosphorus-accumulating organisms (DPAOs). Optimize glycerol dosage (calculated in chemical oxygen demand) could be estimated based on 6 times the effluent NO3−-N of the anoxic zone. As glycerol dosage increased, the relative abundance of fermentation bacteria surged from 8.2% to 17.7%, subsequently boosting the DPR rate from 34.6% to 77.2%. Notably, denitrifying glycogen-accumulating organisms (DGAOs) decreased from 0.5% to 0.2% but remained instrumental in nitrogen removal. The collaborative actions of fermentation bacteria, DPAOs, and DGAOs were vital in upholding the stability of nutrient removal in the glycerol-driven DPR process.
276. 题目: Activation of persulfate by magnetic Mg/Mn–layered double oxide–doped biochar composite for ciprofloxacin removal and bacterial inactivation
文章编号: N23103111
期刊: Separation and Purification Technology
作者: Dongmei Liu, Aiying Guo, Yanling Qi, Zhixin Ji, Hongjuan Li, Xiumei Cao, Zhiwei Zhang, Xinyue Zhang, Kunze Wu, Aijun Cai
更新时间: 2023-10-31
摘要:
Removal of antibiotics and bacteria from wastewater is an effective approach to test the efficacy of catalyst and thus address the issues of water contamination. In this study, a stable magnetic Mg/Mn–layered double oxide–doped biochar composite (MgMnLDO–MBC) was prepared using Lentinula edodes substrate. This composite could further effectively activate the persulfates (PS), such as peroxymonosulfate (PMS) and peroxydisulfate (PDS). MgMnLDO coupling endowed BC and magnetic biochar (MBC) with enhanced surface areas, adsorption sites, and free radicals, which facilitated the improvement of catalytic activity of MgMnLDO–MBC/PS system toward pollutants. MgMnLDO-MBC/PMS system could remove 90.8% of ciprofloxacin (CIP) with 2.8 times the removal efficiency of MBC/PMS system. Density functional theory (DFT) calculation and intermediate analysis showed that the synergistic effect of nucleophilic, electrophilic, and radical active species–mediated reactions improved the removal performance of MgMnLDO–MBC/PMS system. MgMnLDO–MBC/PDS system could efficiently kill 97.6% Escherichia coli and 99.7% Staphylococcus aureus, and destroy the existing biofilms. The effects of composite concentration, PMS loading, pH, temperature, common anions, and humic acid on removal efficiency were also evaluated. After five consecutive cycles, MgMnLDO–MBC/PS system still exhibited high catalytic performance toward CIP removal and bactericidal ability. Results of quenching and electron spin resonance (ESR) showed that ·SO, ·OH, 1O2, and charge transfer were together involved in CIP removal, with ·SO playing a major role. Furthermore, the double–layered metal oxide (LDO) and MBC present in MgMnLDO–MBC composites exhibited a strong synergistic effect in the catalytic process, which resulted in higher reactivity and lower leaching rate of metal ions. In this study, an environment–friendly catalyst was prepared using industrial waste and its efficiency for removal of antibiotics and bacteria from wastewater was verified.
277. 题目: Insight into disparate nonradical mechanisms of peroxymonosulfate and peroxydisulfate activation by N-doped oxygen-rich biochar: Unraveling the role of active sites
文章编号: N23103110
期刊: Chemosphere
作者: Battuya Byambaa, Mingizem Gashaw Seid, Kyung Guen Song, Eun-Ju Kim, Donghyun Lee, Changha Lee
更新时间: 2023-10-31
摘要:
In this study, we first comprehensively studied peroxymonosulfate (PMS) and peroxydisulfate (PDS) activation mechanisms using N, O codoped sludge biochar (NOSB) to degrade organics from water. Among the catalysts, NOSB with a higher content of graphitic N, optimal edge nitrogen (pyridinic N and pyrrolic N), C
O groups, sp2-hybridized C, and rich defects were demonstrated to be a superior catalyst. Therefore, by activating PDS and PMS, NOSB exhibited the highest rate of BPA degradation, which was 22-fold and 13-fold that of pristine sludge biochar, respectively. However, owing to different oxidation potentials and molecular structures, PMS and PDS show different degradation performances due to various catalytic mechanisms occurring, even with the same biochar. Due to the asymmetrical structure of PMS, electrons passed from PMS to NOSB and further generated singlet oxygen (1O2), which governs the degradation of bisphenol A with an auxiliary contribution of single electron transfer. Meanwhile, PDS is reduced at the Lewis basic sites of NOSB, forming inner-surface-bound {PDS-NOSB}, which was oxidizing around neighboring carbon and decomposed targets through transferring single and double electrons. NOSB is promising for practical applications because of its adaptation to a wide pH range, anions, high total organic carbon removal, tunable active sites, and re-usability for degrading organics via PMS/PDS activation. This study unveils knowledge about N, O codoped sludge biochar catalysts for activating PMS/PDS and advocates a great approach for organics’ degradation in the environment.
278. 题目: Deciphering the bioavailability of dissolved organic matter in thermophilic compost and vermicompost at the molecular level
文章编号: N23103109
期刊: Bioresource Technology
作者: Dingmei Wang, Liwen Mai, Zhen Yu, Kongtan Wang, Ze meng, Xiongfei Wang, Qinfen Li, Jiacong Lin, Dongming Wu
更新时间: 2023-10-31
摘要:
Studies on compost dissolved organic matter (DOM) previously focus on its decomposition and humification, without considering DOM bioavailability to understand compost fertility. To decipher the fertility basis of compost, DOM bioavailability in thermophilic compost (TC) and vermicompost (VC) was investigated and linked with its molecular composition. Results showed that DOM bioavailability of VC (36 % BDOC) was generally higher than that of TC (22 % BDOC) due to containing more tannin-like substances. Inversely, only lipid-/carbohydrate-/protein-like substances contributed to DOM bioavailability in TC. Moreover, these differences of bioavailability expanded with C/N decreased in composting materials. Specifically, the %BDOC of VC with N-rich materials (C/N < 25) was 2.1–3.0 times higher than that in TC, while it was only 1.2–1.4 times for C-rich materials (C/N < 25), because N-surplus facilitated the formation of O-/N-containing aromatics (e.g., CHON and tannin) in VC, but inhibited the decomposition of organic materials into small bioactive molecules in TC.
279. 题目: Visible light-driven LaFeO3-biochar composites for removal of sulfamethoxazole by enhanced electron transfer coupled with peroxymonosulfate
文章编号: N23103108
期刊: Separation and Purification Technology
作者: Yanrong Lu, Yingbo Dong, Wei Liu, Junfei Liu, Qi Jin, Lili Zheng, Hai Lin
更新时间: 2023-10-31
摘要:
In this study, we prepared a novel biochar and LaFeO3-bonded nanosphere composite (LFBC) using a co-precipitation-pyrolysis method for the degradation of sulfamethoxazole (SMX). Under visible light conditions, LFBC-activated peroxymonosulfate (PMS) completely removed SMX within 25 min with rate constants 23 and 59 times higher than those of LaFeO3 and biochar, respectively. Both free radical and non-free radical pathways participated in the SMX degradation process, with the non-free radical pathway playing a primary role. It is noteworthy that the interaction between LaFeO3 and Biochar facilitated electron transfer and active sites, promoted the redox cycle of Fe3+/Fe2+, and greatly enhanced the catalytic performance of the composites. Degradation pathway and toxicity evaluation of pollutant removal processes in LFBC/PMS/vis systems based on intermediate identification and Fukui function calculations. This work proved the excellent synergistic performance of LFBC in light utilization and PMS activation, providing a potential utilization for efficient treatment of antibiotic wastewater and antibiotic-resistant bacteria.
280. 题目: Soil organic carbon stocks in European croplands and grasslands: How much have we lost in the past decade?
文章编号: N23103107
期刊: Global Change Biology
作者: Daniele De Rosa, Cristiano Ballabio, Emanuele Lugato, Matteo Fasiolo, Arwyn Jones, Panos Panagos
更新时间: 2023-10-31
摘要: The EU Soil Strategy 2030 aims to increase soil organic carbon (SOC) in agricultural land to enhance soil health and support biodiversity as well as to offset greenhouse gas emissions through soil carbon sequestration. Therefore, the quantification of current SOC stocks and the spatial identification of the main drivers of SOC changes is paramount in the preparation of agricultural policies aimed at enhancing the resilience of agricultural systems in the EU. In this context, changes of SOC stocks (Δ SOCs) for the EU + UK between 2009 and 2018 were estimated by fitting a quantile generalized additive model (qGAM) on data obtained from the revisited points of the Land Use/Land Cover Area Frame Survey (LUCAS) performed in 2009, 2015 and 2018. The analysis of the partial effects derived from the fitted qGAM model shows that land use and land use change observed in the 2009, 2015 and 2018 LUCAS campaigns (i.e. continuous grassland [GGG] or cropland [CCC], conversion grassland to cropland (GGC or GCC) and vice versa [CGG or CCG]) was one of the main drivers of SOC changes. The CCC was the factor that contributed to the lowest negative change on Δ SOC with an estimated partial effect of −0.04 ± 0.01 g C kg−1 year−1, while the GGG the highest positive change with an estimated partial effect of 0.49 ± 0.02 g C kg−1 year−1. This confirms the C sequestration potential of converting cropland to grassland. However, it is important to consider that local soil and environmental conditions may either diminish or enhance the grassland's positive effect on soil C storage. In the EU + UK, the estimated current (2018) topsoil (0–20 cm) SOC stock in agricultural land below 1000 m a.s.l was 9.3 Gt, with a Δ SOC of −0.75% in the period 2009–2018. The highest estimated SOC losses were concentrated in central-northern countries, while marginal losses were observed in the southeast.