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81. 题目: Optimizing organic nitrogen substitution for environmental and economic performance in Chinese solar-greenhouse vegetable production: Evidence from a 13-year field experiment and carbon pricing analysis
文章编号: N26101103
期刊: Journal of Cleaner Production
作者: Nan An, Jianshuo Shi, Liying Wang, Beier Shang, Bingyan Wu, Qing Chen, Yangyang Li, Zhou Jia
更新时间: 2026-10-11
摘要: Intensive greenhouse vegetable production relies heavily on synthetic nitrogen (N) fertilizers and contributes substantial greenhouse-gas (GHG) emissions, yet evidence that organic-N substitution can reduce those emissions while remaining profitable comes mostly from short-term trials. Here, a 13-year randomized tomato–cucumber rotation experiment in a Chinese solar greenhouse was combined with a cradle-to-farm-gate life-cycle assessment and a 30-year techno-economic analysis to compare five fertilization strategies; robustness was tested with a one-at-a-time sensitivity analysis, a 10,000-iteration Monte Carlo uncertainty analysis, and simulations at Chinese, U.S., and European carbon-price levels. In the balanced treatment, replacing 50% of synthetic N with N from pig manure and maize straw simultaneously achieved the lowest product carbon footprint, 1870 kg CO2-eq per tonne of fresh vegetables, 17.3% below the conventional over-fertilization baseline. Annual revenue reached approximately US$102,800 per hectare, and the 30-year net present value was positive. In contrast, direct composting and return of crop vines raised total emissions by 4.7% on a per-hectare basis relative to the conventional baseline. Fertilization management dominated environmental differences across scenarios, whereas labor cost constituted the major source of economic uncertainty, whereas carbon pricing increased emission-reduction revenue without altering the strategy ranking. These results provide long-term field evidence that appropriately designed organic-N substitution can align climate mitigation with farm economics in intensive protected-vegetable systems, and they caution against treating organic inputs as inherently low-carbon without a full life-cycle evaluation.

82. 题目: Plant quality and microbial communities shape particulate organic carbon and mineral-associated organic carbon in alpine meadow soils
文章编号: N26101102
期刊: Plant and Soil
作者: Yueyue Hou, Xiaoping Wang, Lanfang Guo, Hongjiao Wang, Rui Xiao, Jiajia Zhang, Zhongling Yang
更新时间: 2026-10-11
摘要: Aims Although particulate organic carbon (POC) and mineral-associated organic carbon (MAOC) are the two core components of soil organic carbon, they differ fundamentally in their formation and stabilization mechanisms. Nevertheless, how plant communities with different dominant species regulate the accumulation of these two carbon fractions remains poorly understood. Methods To address this knowledge gap, we selected five plant communities in an alpine meadow on the Qinghai-Tibet Plateau (four dominated by Kobresia capillifolia, Elymus nutans, Ligularia virgaurea, and Astragalus membranaceus, and a fifth typical community with mixed species composition) to investigate how dominant species regulate POC and MAOC accumulation. Results Compared with the typical community, the K. capillifolia community had higher POC but lower MAOC, while the E. nutans community showed higher MAOC content. POC accumulation was positively associated with the plant lignin/N ratio and negatively associated with Proteobacteria abundance. In contrast, MAOC accumulation was negatively associated with the lignin/N ratio.. Moreover, the study also showed a significant negative correlation between POC and MAOC, indicating functional differentiation between the active (POC) and stable (MAOC) carbon pools. Conclusions This study reveals that shifts in dominant plant species alter plant input quality and microbial community composition, thereby reshaping soil carbon pool structure and function in alpine meadows on the Qinghai-Tibet Plateau. These findings offer critical insights into soil carbon dynamics in alpine ecosystems under future climate change scenarios.

83. 题目: Digestate-Derived Biochar Modulates Valuable Lactic Acid Production from Food Waste Fermentation: Comparison of Hydrochar and Pyrochar
文章编号: N26101101
期刊: ACS Sustainable Chemistry & Engineering
作者: Qiwei Jian, Hongcheng Peng, Yueji Chen, Yuan Li, Shuanglan Cheng, Xianbao Xu, Xu Duan, Wenjuan Zhang, Xiang Li, Jacek Makinia
更新时间: 2026-10-11
摘要: Bioconversion of food waste (FW) into lactic acid represents a sustainable strategy for circular resource recovery. However, lactic acid production is often limited by rate-limiting hydrolysis and competitive metabolic diversion in mixed-culture systems. This study systematically investigated the regulatory mechanisms of digestate-derived hydrochar and pyrochar in lactic acid production. Hydrochar and pyrochar significantly enhanced lactic acid production to 17.86 ± 2.76 (HC-20) and 19.06 ± 2.54 g COD/L (PC-15), which increased by 80% and 93% than the blank, respectively. However, the different performance mechanisms were shown in different biochar amendment reactors. Hydrochar primarily enhanced substrate solubilization and diminished volatile fatty acid (VFA) production by acting as a physicochemical buffer. Analysis showed that hydrochar selectively enriched acid-tolerant Lactobacillus. Conversely, pyrochar accelerated substrate utilization through interspecies cooperation, establishing a syntrophic partnership between hydrolytic bacteria and lactic acid bacteria. Additionally, both hydrochar and pyrochar maintained a favorable pH (5.11 ± 0.6) and reductive conditions (ORP < –200 mV). The genes encoding key enzymes (e.g., glucokinase and fructokinase) involved in the Embden–Meyerhof–Parnas (EMP) pathway were 4.05–68.76-fold higher than those of the blank. These findings elucidate the distinct regulatory mechanisms of biochar on mixed-culture microbiomes. Furthermore, the biochar was prepared from fermented residues, highlighting the potential of this approach to achieve resource cycling.

84. 题目: High-sensitivity heavy metal toxicity detection by Acinetobacter baylyi C8: Association with EPS protein deficiency
文章编号: N26101018
期刊: Bioresource Technology
作者: Bo Cao, Yue Yi, Beizhen Xie, Hong Liu
更新时间: 2026-10-10
摘要: Heavy metal contamination remains a persistent threat to water quality and ecological safety. Although electroactive microorganism (EAM)-based sensing technologies have shown promise for toxicity monitoring, their practical application is constrained by limited sensitivity. Here, we developed a strategy to improve monitoring performance by identifying and exploiting heavy metal-sensitive EAMs from mixed microbial communities. We successfully identified and isolated Acinetobacter baylyi C8 as a highly sensitive strain by integrating metagenomic analysis of mixed EAM communities under metal stress with electrochemical plate-based isolation. In bioelectrochemical sensing systems, C8 showed current-inhibition responses to eight representative heavy metals that were approximately one order of magnitude higher than those of mixed EAMs. For Cd2+ and Pb2+, good linear responses were obtained, with detection limits of 0.0157 and 0.0205 mg/L, respectively. C8 also responded consistently to binary and ternary heavy metal mixtures, while common coexisting ions caused little interference with Cd2+ and Pb2+ responses. Stable performance was maintained in drinking water, river water, and lake water, with deviations below 5 %. Further analyses showed that the high sensitivity of C8 was associated with low protein content in extracellular polymeric substances (EPS), greater intracellular metal accumulation, and stronger oxidative, metabolic, and electron-transfer disturbances. Overall, this study provides a practical route for identifying heavy metal-sensitive EAMs from mixed communities and highlights their potential for improving bioelectrochemical monitoring of heavy metal toxicity in water environments.

85. 题目: Fe3O4 nanoparticles decorated biochar for activation of peracetic acid through enhanced electron transfer to achieve efficient tetracycline degradation
文章编号: N26101017
期刊: Separation and Purification Technology
作者: Feng Shao, Ziwei Zeng, Huixuan Zhang, Ruohan Zhang, Xudong Yang, Wen Liu, Wenhui Xu
更新时间: 2026-10-10
摘要: Peracetic acid (PAA)-based advanced oxidation processes (AOPs) are demonstrated as efficient technologies for emerging contaminants degradation, while the degradation mechanism and reaction route need further exploration. In this study, a heterogeneous PAA activation system by using magnetite nanoparticles decorated biochar (nFe3O4/BC) was developed for tetracycline (TC) degradation in water. The optimized material (15 wt% nFe3O4/BC) could efficiently activate PAA, achieving as high as 95.3% of TC degradation within 10 min. Combined EPR, scavenging, and electrochemical analyses indicated that coupling nFe3O4 with BC altered the PAA activation pathway, with interfacial electron transfer making a major contribution to TC degradation rather than enhanced radical generation alone. The Fe3O4–BC interface promoted interfacial charge transfer and electronically coupled TC oxidation with PAA reduction. DFT calculations further showed that interfacial coupling shifted the Fe d-band center toward the Fermi level, while Bader charge analysis revealed a transfer of approximately 1.07 e from nFe3O4 to BC, supporting substantial charge redistribution across the interface. Furthermore, Fukui analysis identified N21 and N19 as susceptible sites for electrophilic attack, consistent with the observed TC degradation pathways involving primarily demethylation and hydroxylation. Overall, the developed nFe3O4/BC material exhibited promising application potential in the degradation of antibiotics in water.

86. 题目: Adsorptive removal of PFAS alternatives by pyrolysis-temperature-dependent biochars and activated carbon: Mechanistic insights from surface interactions and XPS depth profiling
文章编号: N26101016
期刊: Journal of Environmental Chemical Engineering
作者: Minhee Kim, Seunghun Hyun, Junho Han
更新时间: 2026-10-10
摘要: Emerging PFAS alternatives, including GenX and F53B, persist through conventional water treatment processes, requiring improved adsorbents and mechanistic understanding. This study investigated the adsorption behavior of GenX and F53B on Miscanthus-derived biochars produced at 400 and 700 °C (BC400 and BC700, respectively) and on activated carbon (AC). Equilibrium adsorption, kinetic, thermodynamic, and X-ray photoelectron spectroscopy (XPS) depth-profiling analyses were combined to clarify how adsorbent structure and PFAS molecular properties regulate adsorption and retention. Adsorption coefficients followed the order BC400 < BC700 < activated carbon, and F53B showed substantially higher affinity than GenX on all adsorbents. Pseudo-second-order kinetic fitting and intraparticle diffusion analysis indicated rapid initial uptake followed by slower internal mass transfer, with faster uptake for F53B. Thermodynamic parameters showed spontaneous, exothermic, and predominantly physical adsorption. BC400 provided an oxygenated, polar, micropore-dominated environment, whereas BC700 exhibited greater carbonization and mesopore development, which were associated with stronger adsorption and contributions from hydrophobic association and pore-assisted retention. Nevertheless, the normalized C–F signal decreased over successive XPS etching stages for both biochars. AC showed the highest adsorption affinity, the fastest uptake, and the least attenuated C–F signal, consistent with greater accessibility within the analyzed subsurface region. Overall, effective adsorption of PFAS alternatives depends on the combined effects of PFAS molecular properties, adsorbent surface chemistry, and pore accessibility.

87. 题目: Crop-rotation legacy effect on soil organic carbon availability interacts with rewetting extents to drive shifts in nitrogen transformation rates
文章编号: N26101015
期刊: Soil Biology and Biochemistry
作者: Lillian Hearn, Taleta Bailey, Johannes Friedl, Naoya Takeda, Robert Kirkby, Helen Suter, Peter Grace, Roger Armstrong
更新时间: 2026-10-10
摘要: Soil organic carbon (SOC) availability and soil moisture play important regulatory roles in nitrogen (N) turnover in agricultural soils; however, the associated gaseous N losses linked to N turnover processes remain poorly understood. A microcosm study was conducted using soils from the Sustainable Crop Rotations in Mediterranean Environments (SCRIME) long-term field trial located on a Vertisol in Victoria, Australia, to investigate the interaction between SOC and soil moisture across a collection of N turnover processes as well as the magnitude and production pathways of N2O and N2. A rewetting treatment was imposed at three water-filled pore space (WFPS) thresholds: 60% (aerobic), 75% (partially anaerobic) and 90% (anaerobic), using surface soil (0–10 cm) collected from the wheat phase of four contrasting crop rotations. Soils were incubated for 48 h following rewetting. A triple 15N isotope labelling approach combining pool dilution assays with the 15N gas flux method was used to (i) quantify gross N turnover rates of mineralisation, nitrification, ammonium immobilisation, and nitrate consumption, (ii) partition N2O emissions into nitrification-derived (N2On) and denitrification-derived (N2Od) sources, and (iii) quantify N2 emissions. Nitrogen turnover processes and gaseous N losses were strongly regulated by WFPS, while long-term crop rotation treatments significantly (p < 0.05) affected nitrate consumption, ammonium immobilisation and nitrification rates. Rewetting events triggered a pronounced pulse of N transformation activity, with the largest denitrification losses occurring at 90% WFPS, reaching up to 6.74 μg N2Od-N g−1 soil day−1 and 7.31 μg N2-N g−1 soil day−1.

88. 题目: Co-pyrolysis of chestnut shell and waste PET for lanthanum-functionalized biochar: In-situ gas-solid carbonation and non-pore-limited phosphate recovery
文章编号: N26101014
期刊: Journal of Environmental Chemical Engineering
作者: Zhanghong Wang, Yixing Li, Weijia Li, Shuang Li, Tao Lu, Qichang Wang, Ke Jiang, Jiegang Liu, Taoze Liu
更新时间: 2026-10-10
摘要: Understanding the interfacial volatile-minerals interaction during biomass-plastic co-pyrolysis is crucial for tailormaking functionalized biochar materials for environmental applications. Herein, lanthanum-functionalized biochars were synthesized via low-temperature (400 ℃) co-pyrolysis of agricultural chestnut shell (CS) and waste polyethylene terephthalate (PET) within an oxygen-limited micro-reactor sealed by an aluminum-foil-shielded ceramic crucible. This confined boundary was expected to prolong the residence time of internally evolved pyrolytic volatiles (notably CO2 released from PET chain scission and biomass depolymerization), thereby facilitating in-situ gas-solid carbonation. Structural and spectroscopic analyses (XRD, FTIR, and XPS) confirmed that the thermally decomposing La-precursors were dynamically converted into hexagonal lanthanum dioxycarbonate (La2O2CO3) and cubic La2O3 mineral phases embedded on the graphitized biochar framework, facilitating the in-situ generation of functional carbonate-bearing mineral phases. Severe mineral growth at a high La loading density (2.0 mmol/g) partially clogged the porous carbon channels, causing the specific surface area of the biochar to decrease to 8.61 m2/g. Nevertheless, the composite exhibited the highest phosphate adsorption performance among the prepared biochars, with a theoretical maximum monolayer adsorption capacity of 20.29 mg/g. Combined kinetic fitting and spectroscopic characterizations revealed that phosphate capture was predominantly governed by chemical interactions at the active La-bearing sites via inner-sphere ligand exchange and the formation of monoclinic LaPO4, rather than by physical pore entrapment. This work elucidates the in-situ pyrolytic carbonation mechanisms during waste co-pyrolysis and provides a sustainable strategy for converting dual wastes into high-performance materials for environmental remediation and nutrient recovery.

89. 题目: Pathways of soil organic carbon stabilization driven by long-term straw returning practices in a rainfed agroecosystem
文章编号: N26101013
期刊: Geoderma
作者: Gu Fengxue, Wang Hetan, Yang Zhenxing, Zhou Huaiping, Zhang Wenju, Sun Dongbao, Mei Xurong, Li Suhang
更新时间: 2026-10-10
摘要: Enhancing soil organic carbon (SOC) stability is a central strategy for achieving carbon sequestration, emission reduction, and sustainable soil fertility improvement in rainfed agroecosystems. Straw returning is a widely adopted practice to increase SOC stocks, yet the microbially mediated mechanisms by which different straw return modes regulate SOC stabilization remain poorly constrained, particularly across the Loess Plateau of China. Here, we leveraged a 30-year field experiment in a rainfed maize system to compare three straw return strategies under equivalent carbon input: straw mulching (S1), shredded straw incorporation (S2), and livestock digestion return (S3). We integrated physical aggregate fractionation with multi-biomarker analyses (lignin phenols, amino sugars, and phospholipid fatty acids) and extracellular enzyme assays to elucidate the divergent pathways of SOC stabilization. Our results demonstrated distinct carbon stabilization pathways among the three treatments. S1 followed a physical protection pathway, characterized by the highest fungal-to-bacterial ratio and the preservation of plant-derived lignin within macroaggregates, but resulted in a limited SOC increase (+15.56 %) and low carbon conversion efficiency (+17.45 %). S2 represented an intermediate fungal decomposition pathway; although lignin phenol content increased significantly across all aggregate fractions, high ligninolytic enzyme activities consumed substantial carbon, yielding a moderate SOC gain of + 19.44 %. In contrast, S3 achieved synergistic stabilization via microbial transformation. The low C/N ratio of manure alleviated nutrient limitation, fostering a bacterial- and actinobacterial-dominated community (reaching 84.96 nmol·g−1 PLFA in microaggregates) and upregulating hydrolytic enzyme activities by 73.93 %–193.65 %. This shift promoted the formation of microaggregates (+21.18 %) and silt–clay particles (+40.55 %), with microbial necromass contributing > 40 % to stable SOC pools. Consequently, S3 maximized SOC storage with a 40.00 % increase and achieved the highest carbon conversion efficiency (+29.15 %). These findings highlight that livestock-mediated straw return optimizes the continuum of bacterial proliferation, microaggregate assembly, and microbial necromass accrual, representing an effective strategy for enhancing both the magnitude and long-term stability of SOC in dryland agroecosystems on the Loess Plateau.

90. 题目: Cadmium bioavailability during flooding–drainage in paddy soils: Spatiotemporal associations with dissolved organic matter transformation and iron speciation
文章编号: N26101012
期刊: Journal of Cleaner Production
作者: Zhen Wang, Chuangchuang Zhang, Danlei Lv, Xiaoning Liu, Xiaoxue Ouyang, Ziyun Liu, Dongfei Tan, Qiusheng Chen, Qiang Zhang, Yujie Zhao
更新时间: 2026-10-10
摘要: The mechanism underlying the coupled regulation of Cadmium (Cd) activity by Iron (Fe) oxides and dissolved organic matter (DOM) in farmland soils during flooding followed by drainage remains unclear. This study addressed this issue by combining spatial sampling (n = 94) and time-series experiments to elucidate the Fe–DOM–Cd interaction mechanism using the diffusive gradients in thin films (DGT) technique. Regional surveys showed that 83.6% of soils in the study area were acidic, with an average total Cd content of 0.5 mg kg−1, indicating a substantial Cd pollution risk. Examination of soil properties revealed that the initial release fraction of Cd was dominated by organic-bound components and that Fe oxides could indirectly inhibit Cd activity. This study further selected two soils (AH and HS, respectively collected from Anhua and Heshan districts of Hunan Province, China) with similar total contents of Fe, Cd, and organic matter to investigate the differential mechanisms underlying Cd activity regulation during flooding and drainage periods. HS soil consistently contained higher amorphous Fe content than AH soil, and its labile Fe content was 18.3 times that of AH soil after 1 d of flooding. The increase in labile and amorphous Fe in HS soil coincided with a marked decrease in Cd availability after 5 d of flooding, whereas the corresponding decrease in AH soil was substantially delayed. DOM characteristics considerably differed between flooding and drainage periods. AH soil DOM showed higher aromaticity and humification, while HS soil DOM exhibited a cyclic transformation from protein-like substances to humus and back to protein-like substances. Parallel factor analysis identified two major fluorescent components, namely, terrestrial humus (C1) and tryptophan-like substances (C2). During HS soil flooding, C1 proportion increased from 26% to 88%, while during the early AH soil flooding stage, it exceeded 85%. The concurrent increase in labile Fe and DOM humification was associated with the stronger decline in Cd availability in HS soil, suggesting a potential coupled influence of Fe transformation and DOM evolution on Cd dynamics. Overall, this study provides a theoretical reference for Cd risk regulation in contaminated paddy fields.

91. 题目: Effect of KOH activation on the structural properties of durian peel biochar and its performance for PET microplastic removal
文章编号: N26101011
期刊: Chemosphere
作者: Sudarat Woeisan, Sandhya Babel
更新时间: 2026-10-10
摘要: The persistence of microplastics (MPs) in aquatic environments challenges conventional water treatment systems, increasing demand for sustainable removal materials. This study investigated the influence of KOH activation on the structural properties of durian peel biochar and its performance for polyethylene terephthalate (PET) microplastic removal from aqueous systems. Batch experiments evaluated biochar modification, contact time, and solution pH. Physicochemical characterization revealed that KOH activation substantially enhanced surface area, pore development, and surface structural complexity. Post-adsorption FE-SEM showed PET retention on rough surfaces, cracks, and structural cavities, while XPS revealed an increase in the O/C atomic ratio from 0.13 to 0.21 and the appearance of an ester-related O–CO component, supporting PET retention on the biochar surface. Under optimum conditions (4 g L−1, pH 5, 180 min), KOH-activated biochars achieved PET removal efficiencies of 86.83-90.50%, substantially higher than unactivated biochars (51.00-51.17%) and comparable to commercial activated carbon (88.50%). PET removal decreased with increasing pH, indicating that solution chemistry influenced PET-biochar interactions. The pseudo-first-order model provided the best empirical description of the time-dependent PET retention behavior under the investigated conditions. Considering the large PET particle size (20-53 μm) relative to the predominantly microporous structure, enhanced removal was attributed primarily to accessible external-surface retention and physicochemical interactions rather than direct micropore filling. These findings demonstrate that KOH activation effectively improves the structural properties and PET retention performance of durian peel biochar, highlighting its potential as a bio-based material for microplastic mitigation.

92. 题目: Sources of particulate and sedimentary organic matter in the middle Okinawa Trough since the Last Glacial Maximum: Implications for lateral transport across the East China Sea shelf
文章编号: N26101010
期刊: Palaeogeography, Palaeoclimatology, Palaeoecology
作者: Libo Wang, Xilin Zhang, Bin Zhai, Mingyu Zhang, Jingtao Zhao, Xianrong Zhang, Zhilei Sun, Bangqi Hu, Yong Zhang
更新时间: 2026-10-10
摘要: Provenance analysis of organic matter in the Okinawa Trough (OT) is essential for understanding organic carbon dispersal and budget in the Eastern China Marginal Seas. To determine the sources of organic matter and the factors controlling provenance changes in the OT, this study analyzed the concentrations and stable isotopic compositions of particulate organic carbon and particulate nitrogen in water column, together with the contents and stable isotopic compositions of total organic carbon and total nitrogen in a piston core. During summer, approximately 76 ± 21% of particulate organic matter in the OT is estimated to be derived from Taiwan rivers, whereas marine organic matter accounts for the remaining 24 ± 21%. Sedimentary organic matter in the OT has been predominantly marine in origin since 19.5 ka. The OT serves as an important sink for primary production on the East China Sea (ECS) shelf. During high sea-level stage, approximately 81 ± 8% of sedimentary organic matter in the OT is estimated to be supplied from the ECS shelf through near-bottom lateral transport, whereas vertical settling of particulate organic matter from the overlying water column accounts for the remaining 19 ± 8%. Enhanced marine primary production led to an increased contribution of marine organic matter during the Holocene. The contribution of terrigenous organic matter increased during 18–15.2 ka and 13.3–11.5 ka, probably reflecting the intensification of tidal erosion on the ECS shelf, and also increased during 7.3–5.3 ka and 3.2–0 ka, likely associated with the strengthening of the East Asian winter monsoon. Although terrigenous inorganic nitrogen contributes to some extent to the δ15N signature of total nitrogen, terrigenous organic nitrogen input and organic matter degradation exert insignificant influences. The decreasing sedimentary δ15N record is consistent with an increased importance of marine nitrogen fixation from the Last Glacial Maximum to the middle and late Holocene.

93. 题目: Late-Holocene organic carbon accumulation in glacier-fed lakes on the Tibetan Plateau: regional patterns and sediment-routing processes
文章编号: N26101009
期刊: Palaeogeography, Palaeoclimatology, Palaeoecology
作者: Tianlong Yan, Chun Wang, Sitong Liu, Ying Li, Junjiang Dong, Qi Zhang, Xiaoru Zhang, Xiaomin Gao, Xiaoshuang Sun, Jinliang Liu, Can Zhang
更新时间: 2026-10-10
摘要: Glacier-fed lakes may archive organic carbon accumulation through a transfer pathway in which glacier dynamics influence sediment production, hydrological routing, and burial efficiency. However, the relative importance of sediment burial versus organic-matter supply remains poorly constrained on the Tibetan Plateau (TP). We reconstructed a 3500-year, core-based organic carbon accumulation rate (CAR) record from Tian'E Lake (TE Lake), a small glacier-influenced lake on the northern TP, using total organic carbon (TOC), sediment accumulation rate (SAR), estimated dry bulk density (DBD), and n-alkanes. We compared the record with independent proxies of glacier activity, hydroclimate, lake-water temperature, aeolian activity, and grazing, and synthesized records from nine additional glacier-fed lakes. TE Lake CAR increased overall, with a mean of 37.74 g C m−2 yr−1 and a maximum of 169.52 g C m−2 yr−1 at 1714 CE within a broader 1560–1740 CE high-CAR interval. This maximum coincided with a several-fold rise in SAR, the highest TOC value, and elevated total n-alkane flux. The relative behavior of these variables indicates that rapid sediment burial was likely the primary control, while enhanced organic-matter supply or preservation amplified the peak. The regional compilation shows increasing standardized CAR and SAR in the central and northeastern TP group but declining trends in the three available western records. Given sparse western coverage and strong inter-lake heterogeneity, this apparent regional contrast is considered provisional. This study highlights the importance of glacier-conditioned sediment routing and rapid burial in regulating lacustrine carbon accumulation.

94. 题目: Can the Carbon Storage Function of a Degraded Mountain Wet Meadow Be Restored?
文章编号: N26101008
期刊: Journal of Geophysical Research: Biogeosciences
作者: David J Cooper, Andrew W Swift, Evan C Wolf, Katherine Miller, Lydia Baldwin, Melissa Booher, John A Hribljan
更新时间: 2026-10-10
摘要: Sierra Nevada meadows experienced intense livestock grazing in the 19th century, resulting in a shift from deep‐rooted highly productive perennial clonal sedges to short‐lived and shallow‐rooted plants. The current meadow vegetation contains >20% bare ground and <10% cover of highly productive clonal sedges and rushes. We hypothesized that the existing vegetation was insufficiently productive to have formed or to maintain the 2000‐year‐old carbon‐rich meadow soils. We established a multiyear experiment (2016–2019) to determine if planting Carex scopulorum seedlings into Tuolumne Meadows in Yosemite National Park could reverse the impacts of legacy grazing and restore the soil carbon storage function. Planted C . scopulorum had a high 4‐year survival rate (75.2%) with slow but significantly increasing belowground biomass production (1.34 g plant −1 yr −1 ). Field‐measured and gap‐fill modeled carbon fluxes indicate an annual average ecosystem respiration (ER) of 0.96 kg C m −2 yr −1 and gross primary production (GPP) of 0.59 kg C m −2 yr −1 , resulting in a net ecosystem exchange loss of 0.37 kg C m −2 yr −1 . This represents an annual loss of 1.3% of the 29.4 kg C m −2 of soil organic carbon (SOC). The transplanted sedges would need to increase meadow GPP by 63%, or ER decreases by 39%, to achieve a net annual storage of SOC to reestablish the processes that formed the organic rich soil. Active planting to increase the currently sparse high‐productivity plant species is a good option to boost GPP, but climate change could accelerate ER and increase net ecosystem carbon loss.

95. 题目: Diagenetic pathways and preservation of bulk and amino acid δ15N in bivalve shell organic matter across the Holocene to the Pliocene
文章编号: N26101007
期刊: Geochimica et Cosmochimica Acta
作者: Qian Huang, Kirsty E H Penkman, Ellie Nelson, Daniel Vigelius, Thomas Tütken, Lukas Fröhlich, Bernd R Schöne
更新时间: 2026-10-10
摘要: Nitrogen isotope (δ15N) records preserved in mollusc shells have strong potential to reconstruct changes in nitrogen sources, transformations and transport in the ocean beyond instrumental observations. This is because mollusc shells can be precisely dated and often preserve highly temporally resolved records. In addition to bulk nitrogen isotope analysis, compound-specific nitrogen isotope analysis of amino acids (CSIA-AA) further enables the separation of biogeochemical processes from the trophic effects. However, the extent to which bulk and amino acid-specific δ15N are preserved in shell-bound organic matter in (sub-)fossil materials over the multi-millennial to multi-million-year timescales remains poorly understood. Furthermore, intra-crystalline organic matter (intra-OM), which is encapsulated inside calcium carbonate biomineral units, has not been systematically evaluated for its ability to preserve original isotopic signals relative to total shell organic matter (total-OM). Here, we investigate the effects of diagenesis on bulk and amino acid-specific nitrogen isotope compositions in the shell-bound organic matter (both intra-OM and total-OM) of the long-lived bivalve Arctica islandica, a well-established geochemical archive in the North Atlantic. We analysed live-collected and sub-fossil shells spanning the Holocene from the northern North Sea and fossil specimens from several Crag formations in East Anglia, UK, dating to Plio-Pleistocene. Using spectroscopic, chemical, and isotopic approaches, we assessed the preservation of the biomineral structure, shell organic chemistry and nitrogen isotope compositions in bulk shell organic matter (δ15NBulk) and their amino acids (δ15NAA). Only minimal modifications of the original aragonitic shell mineralogy were detected as indicated by low (<5 %) calcite content in all specimens analysed from the different studied time periods (Plio-Pleistocene, Early or Mid-Holocene, Late Holocene and Modern). Then we identified a diagenetic trajectory in which inter-crystalline organic matter was progressively lost through open-system interactions during taphonomy, reflected by declining nitrogen content and convergence of amino acid compositions between total-OM and intra-OM. In contrast, intra-OM remained physically protected within the biomineral matrix and retained nitrogen over ca. 2–3 million years, despite internal molecular reorganisation including peptide hydrolysis and selective loss of labile amino acids (e.g., serine and threonine). Given lack of net nitrogen loss, intra-OM showed robust preservation of δ15NBulk. However, while δ15NAA of intra-OM in Holocene shells retained patterns consistent with limited diagenetic alteration, CSIA-AA δ15N patterns in Plio-Pleistocene shells deviated from the Holocene pattern, even within intra-OM, with changes in the relative isotope spacing among amino acids associated with degradation. These findings provide a mechanistic framework linking organic matter preservation and nitrogen isotope preservation in molluscs shell biomineral archives and highlight intra-OM as a promising substrate for reconstructing past marine nitrogen cycling within certain diagenetic limits.

96. 题目: Humic acid substitution improves soil quality and maize yield under drought and saline–alkaline stress by regulating bacterial community structure
文章编号: N26101006
期刊: Applied Soil Ecology
作者: Shuaihong Chen, Zhijie Chang, Jinxin Yang, Tiantian Hu, Junsheng Lu, Dongwei Li, Jie Liu
更新时间: 2026-10-10
摘要: Humic acid (HA) substitution provides a potential strategy for reducing chemical fertilizer inputs while maintaining crop productivity and soil functions in drought-prone saline–alkaline agroecosystems. However, the optimal HA application rate and its effects on soil quality and microbial communities under reduced water and fertilizer input remain unclear. A two-year field trial was conducted in Xinjiang, China, including two irrigation levels (100% and 80% crop evapotranspiration, ETc) and five fertilization treatments, including conventional fertilization (CT: 300 kg N ha−1, 120 kg P ha−1, and 150 kg K ha−1), reduced fertilization (R, 20% less than CT), and partial substitution of chemical fertilizer with HA at 60 (HAL, 3% substitution rate), 150 (HAM, 7% substitution rate), and 300 (HAH, 14% substitution rate) L ha−1, with total N, P, and K inputs kept equal among the R and HA treatments. Deficit irrigation (80% ETc) reduced maize yield by approximately 5% compared with full irrigation (100% ETc), whereas HA substitution significantly improved crop productivity. Compared with CT, HAM increased maize yield by approximately 12%, achieving the highest yield among fertilization treatments. HA substitution improved soil quality, with HAH showing the greatest improvement in soil quality but a lower yield response than HAM. Compared with chemical fertilizer alone, HA substitution applied in the two-year experiment reduced soil pH, electrical conductivity, total nitrogen, and available nitrogen contents, while increasing total organic carbon, available phosphorus and potassium contents, as well as enzyme activities. HAM enhanced bacterial α-diversity, whereas HAH reduced it, with HA effects on β-diversity varied with irrigation level. Moreover, moderate HA promoted more compact and structured bacterial networks, while high HA input weakened network connectivity. Partial least squares path modeling indicated that bacterial community characteristics exerted stronger associations with soil quality and maize yield than soil physicochemical properties, while enzyme activities positively related to soil quality improvement, which subsequently promoted maize yield. Overall, 150 L ha−1 HA fertilizer substitution combined with 80% ETc is a valuable strategy for sustainable maize production and soil quality improvement in arid saline agricultural regions.

97. 题目: Enhanced Se enrichment and Cd reduction in rice (Oryza sativa L.) by Zr-Mn bimetallic modified biochar in Se-rich and Cd-contaminated soil
文章编号: N26101005
期刊: Ecotoxicology and Environmental Safety
作者: Rifeng Wu, Jiaqi Wei, Weixin Zhang, Jianing Gan, Li Gao, Yi Zhang, Haijiao Tan, Yinghao Mo, Yongxian Liu, Fangming Yu, Yi Li
更新时间: 2026-10-10
摘要: The development of effective amendments for the safe cultivation of rice (Oryza sativa L.) in selenium-cadmium co-contaminated paddy soils poses a significant challenge. This study synthesized a novel Zr-Mn bimetallic modified peanut shell biochar (ZM@PSB) and evaluate its effects on soil health and the accumulation of selenium (Se) and cadmium (Cd) in rice. Characterization revealed that the modification produced a hierarchical porous structure with uniformly dispersed amorphous Zr-Mn (oxy)hydroxides and a wealth of oxygen-containing functional groups, which contribute to its remediation efficacy. The application of ZM@PSB as a soil amendment improved physicochemical properties in a dose-dependent manner, enhanced the availability of carbon, nitrogen, and phosphorus nutrients, increased microbial biomass, and stimulated enzyme activities. This shift transitioned key regulatory factors from a water-dominated regime to a synergistic pH-EC-Eh environment. ZM@PSB immobilized Cd primarily through complexation and precipitation, resulting in a reduction of bioavailable Cd by 24.37–44.61%. Simultaneously, it mobilized residual Se via manganese (Mn) redox cycling and microbial mineralization. In rice, ZM@PSB promoted the formation of root iron plaques, which served as a barrier to Cd translocation and facilitated Se uptake. Additionally, it enhanced the antioxidant system to alleviate Cd-induced oxidative stress. Consequently, the application of high-dose ZM@PSB increased grain Se concentration by 35.88%, with the proportion of organic selenium species (SeCys and SeMet) in rice grains up to 90.55%, while reducing grain Cd by 32.18%. This reduction was achieved through regulated bioaccumulation and translocation. This study demonstrates that ZM@PSB effectively optimizes the soil-plant system, providing a promising strategy for the synergistic production of Se-enriched and Cd-safe rice in contaminated paddies.

98. 题目: Climate‐Linked Si‐Fe Dynamics and Their Associations With Soil Mineral‐Associated Organic Carbon
文章编号: N26101004
期刊: Global Biogeochemical Cycles
作者: Aiquan Shi, Zhaoliang Song, Ji Chen, Zhongkui Luo, Chengjie Ren, Xiaomin Yang, Yidong Wang, Weiqi Wang, Chuancheng Fu, Zhihong Xu, Cong‐Qiang Liu, Changxun Yu
更新时间: 2026-10-10
摘要: Iron (Fe) (hydr)oxides and silicate minerals are key controls on the formation of mineral‐associated organic carbon (MAOC) in soils—a relatively persistent fraction of soil organic carbon (SOC). Silicon (Si) is essential for silicate mineral formation, and the interactions between Fe and Si are widespread in natural environments. However, the interactive effects of Fe (hydr)oxides and Si on MAOC remain poorly understood. Here, we determined Fe and Si speciation in soils across diverse ecosystems by selective extraction, and estimated their individual and interactive effects on MAOC. Our results show that pedogenic and biogenic amorphous Si are positively associated with MAOC accumulation, while more mobile Si forms (including dissolved and weakly adsorbed Si) are negatively associated with the formation of Fe‐bound organic carbon (Fe‐OC). Although amorphous Fe oxides serve as the dominant carriers of Fe‐OC complexes, increasing metal oxide‐associated Si is linked to a reduced contribution of Fe oxides to MAOC. Additionally, temperature and precipitation are associated with variations in Si and Fe speciation, likely through changes in soil weathering stage and pH, and these patterns are further linked to differences in MAOC accumulation. Our results highlight climate‐linked Si‐Fe dynamics and interactions as critical but previously underappreciated factors related to SOC stabilization, and we suggest that Si speciation should be integrated into land management and SOC sequestration strategies across diverse ecosystems.

99. 题目: Metal-dependent effects of post-pyrolysis air oxidation on phosphate adsorption and retention by Fe-, Ca-, and Mg-impregnated biochars
文章编号: N26101003
期刊: Journal of Environmental Chemical Engineering
作者: Yujun Wang, Jie Yuan, Keqin Wang, Lei Hou
更新时间: 2026-10-10
摘要: Metal impregnation is widely used to enhance phosphate adsorption by biochar (BC), but post-treatment may affect different metal-bearing phases in distinct ways. In this study, corn-stover biochar was impregnated with Fe, Ca, or Mg salts and used either without further treatment (NT) or after post-pyrolysis air oxidation (PPAO) to evaluate metal-dependent effects on phosphate adsorption and retention. Metal impregnation markedly enhanced phosphate adsorption and, on a phosphorus (P) basis, logKd increased from 1.79 to 2.27 for pristine biochar to 3.18–4.23 for metal-impregnated biochars, while the Freundlich coefficient (KF) increased from 161 to 1100–15600 mg1−n Ln kg−1. Fe-NT-BC showed the best overall performance among the tested biochars, with the highest KF value of 15600 mg1−n Ln kg−1 and the lowest P desorption percentage of 0.29%. PPAO produced contrasting metal-dependent responses. The KF increased from 1100 to 6600 mg1−n Ln kg−1 for Ca-impregnated biochar, but decreased from 15600 to 11700 for Fe-impregnated biochar and from 2700 to 1400 mg1−n Ln kg−1 for Mg-impregnated biochar. Metal-release tests showed that dissolved Fe in P-containing systems was ≤ 0.046 mg L−1 for Fe-NT-BC and was not detected for Fe-PPAO-BC. Post-adsorption XRD showed no distinct new crystalline metal-phosphate phases. These results demonstrate that PPAO acts as a metal-dependent post-treatment and that Fe impregnation without PPAO provided the best balance of P adsorption and retention among the preparation routes examined.

100. 题目: Halloysite clay nanotube loaded biochar nanocomposite synthesized via co-pyrolysis of ball-milled cellulosic biomass: Implications for soil amendment
文章编号: N26101002
期刊: Journal of Environmental Chemical Engineering
作者: S V Chinna Swami Naik, B P Vellanki, R K Dutta
更新时间: 2026-10-10
摘要: Soil amendment is essential for restoring degraded soils and advancing sustainable agriculture. In this study, a low-cost soil amendment was synthesized via co-pyrolysis of halloysite nanotube (HNT) loaded, ball-milled pinecone biochar nanocomposite (HNT–BNC). The synthesized HNT–BNC were applied to degraded soil to evaluate their potential to improve soil fertility and were compared with soil amended with pristine HNT and nano-biochar. Amendment with 3% (w/w) HNT-BNC increased the soil fertility index by 129.04% relative to degraded soil, primarily due to enhancements in soil organic matter (7.79%), water-holding capacity (38.65%), electrical conductivity (388.76 µS/cm), exchangeable Ca (17.39 cmol/kg), and exchangeable Mg (21.81 cmol/kg). Seed germination assays using HNT–BNC extract solutions showed a relative seed germination of 112.5% and relative radicle growth of 157.81% compared to the control. These improvements are attributed to the favorable cation exchange capacity of HNT–BNC (12.16 cmol/kg), along with the presence of macronutrients (N: 1.27%, S: 0.13%) and micronutrients (Mn: 0.11 mg/kg, Zn: 0.33 mg/kg, Cu: 0.04 mg/kg). Furthermore, the high bulk density (0.63 g/cm3) and large specific surface area (356.47 m2/g) of HNT–BNC reduce storage and transportation requirements, minimize erosion losses due to wind and runoff, and enhance nutrient retention, thereby promoting sustainable agricultural practices.