Search Results (5,619)

Acute kidney injury (AKI) is a frequent complication in critically ill patients and is associated with high morbidity, mortality, and an increased risk of progression to chronic kidney disease (CKD). In this context, nutritional management represents a key component of supportive therapy, as AKI is commonly characterized by hypercatabolism, negative nitrogen balance, and protein-energy wasting. Current nutritional strategies primarily focus on the quantity of protein intake required to compensate for catabolic losses, particularly in patients undergoing renal replacement therapy (RRT). However, growing evidence suggests that the quality and metabolic effects of dietary protein sources may also influence renal physiology and recovery. Plant-based proteins have recently gained attention as a potentially advantageous nutritional strategy in kidney disease. Compared with animal-derived proteins, plant-based proteins are associated with a lower dietary acid load, reduced production of gut-derived uremic toxins, and beneficial effects on the intestinal microbiota. In addition, their amino acid profile may modulate oxidative stress, inflammatory pathways, and renal hemodynamics. These characteristics may contribute to a more favorable metabolic environment in patients with AKI, potentially supporting renal recovery and reducing the risk of AKI-to-CKD transition. This review examines the pathophysiological mechanisms linking protein metabolism, renal injury, and nutritional support in AKI. Particular attention is given to the role of plant-based proteins, their amino acid composition, and their potential nephroprotective effects. Understanding the interaction between dietary protein sources, metabolic pathways, and the gut–kidney axis may help guide future nutritional strategies aimed at improving outcomes in critically ill patients with AKI. Full article

Nanoparticles (NPs) have great potential for stimulating plant growth and development, reducing the negative impact of various types of stress on plants, and increasing the yield of agriculturally important crops. Metal oxide NPs (MONPs) have been shown to have a significant effect on the physiological and biochemical processes in plants, enhancing plant resilience. Among them, CuO, Mn_xO_x, and ZnO NPs are of particular interest because they contain elements essential for plant function. However, widespread use in agrochemistry and plant protection requires a preliminary risk assessment due to their potential phytotoxic effects. Phytotoxicity manifests through the development of oxidative stress, genotoxicity, and transcriptional disruption. A decrease in plant growth and photosynthesis, increased lipid peroxidation (LPO), and the accumulation of toxic NPs in plant tissues were also observed. Among the studied MONPs, CuO and ZnO NPs exhibit the greatest phytotoxic effects. However, the effects of MONPs are dose-dependent. Numerous studies have shown that MONPs can stimulate plant biometric parameters and productivity, as well as influence biochemical processes. MONPs have been shown to influence the functioning of the plant antioxidant system, manifested by modulating the content of reactive oxygen species (ROS), the activity of antioxidant enzymes (AOEs), and the regulation of signaling pathways mediated by ROS and reactive nitrogen species. Furthermore, MONPs influence the accumulation of proline and phenols in plant tissues. MONPs have a pronounced effect on the functioning of the plant photosynthetic apparatus, manifested by changes in pigment content, the activity of photosynthetic enzymes, and the functioning of photosystems. MONPs can improve nutrient absorption, regulate osmotic balance, and activate plant defense mechanisms. ZnO NPs are effective in mitigating salt stress. CuO and Mn_xO_x NPs have shown promise in mitigating biotic stress. Furthermore, these NPs were found to reduce the toxicity of heavy metals to plants. Overall, when used wisely, MONPs hold promise for enhancing the physiological, biochemical, and agronomic performance of crop plants under conditions of global climate change, effectively addressing food security issues. Full article

Improving the effluent quality of municipal wastewater treatment plants (WWTPs) is essential for sustainable water management and water quality protection in the Yellow River Basin. Many existing WWTPs in northern China were constructed under earlier discharge requirements and now face dual challenges of stricter effluent standards and poor low-temperature performance in winter. In this study, a municipal WWTP with a design capacity of 5 × 10⁴ m³/d in northern China was upgraded to improve winter treatment performance and support stable compliance with the discharge requirements of the Yellow River Basin. The original anaerobic + oxidation ditch process suffered from unstable effluent quality, excessive sludge loading, and insufficient pollutant removal under low-temperature conditions. A land-saving retrofit strategy was therefore proposed, involving oxidation ditch wall-height raising to extend the hydraulic retention time (HRT) and membrane bioreactor (MBR) integration to increase the mixed liquor suspended solids (MLSS) concentration. After the retrofit, the total HRT increased to 19.82 h, and the average MLSS concentration reached 7050 mg/L. The relative abundances of key nitrogen-removing bacteria, including Nitrospiraceae, Nitrosomonadaceae, and Rhodocyclaceae, increased markedly. Meanwhile, denitrification sludge loading and BOD₅ sludge loading decreased to 0.030 and 0.033 kg/(kg·d), respectively. Under low-temperature conditions, the theoretical removal capacities of total nitrogen (TN) and BOD₅ reached 44.32 and 286.19 mg/L, respectively, enabling stable effluent compliance. The results show that this retrofit strategy can improve WWTP effluent quality while avoiding large-scale land expansion, providing a practical and sustainable solution for upgrading cold-region WWTPs along the Yellow River Basin. Full article

Low-temperature stress severely restricts the engineering application of anaerobic ammonia oxidation (anammox) technology in municipal mainstream wastewater treatment, leading to its slower large-scale implementation relative to industrial wastewater and reject water treatments. The inhibitory effects of low temperatures on the anammox process cannot be merely ascribed to conventional microbial metabolic responses. Elucidating the specific mechanisms underlying low-temperature impacts on anammox bacteria is therefore critical for formulating targeted mitigation strategies. In this study, a meta-analysis was performed to compare the response patterns of specific anammox activity (SAA) and nitrogen removal rate (NRR) to temperature variations. SAA declines gradually with decreasing temperature, while NRR displays a more dramatic and stepwise reduction. The T₅₀ values (temperature corresponding to 50% of the performance at 30 °C) for these two parameters are 20 °C and 15 °C, respectively. Low-temperature inhibition of anammox is a multifaceted process, encompassing direct physiological disturbances to individual anammox cells and impaired nitrite bioavailability within the microbial community. To address these temperature-related bottlenecks, a conceptual hybrid nitrogen removal system was rationally optimized by integrating conventional strategies with an innovative split-flow influent regulation strategy. This hybrid system is anticipated to enhance the stability and treatment efficiency of anammox under low-temperature conditions, thus facilitating its broader engineering application in cold climate regions. Full article

Sapling survival and growth depend on photosynthetic assimilates. Therefore, improving physiological performance during early stages may enhance subsequent performance and nursery production. This study evaluated whether exogenous oxidized glutathione (GSSG), reported to enhance photosynthesis, improves the photosynthetic, physiological, and growth-related traits of Larix gmelinii var. japonica saplings. Sixteen saplings were assigned to four treatments: GSSG, 5-aminolevulinic acid, Hyponex, and a water control. Photosynthetic, nitrogen-related, and growth traits were measured before treatment and at 3, 6, 13, and 31 days after treatment, and biomass was assessed after three months. The GSSG treatment showed no difference in the net CO₂ assimilation rate (A_max) compared with the control, but exhibited a significantly earlier peak at 6 days than the other treatments. This response was supported by the stability of GSSG-treated saplings against photoinhibition (F_v/F_m) and a tendency toward greater resilience to midday light stress (Φ_PSII). Enhanced photosynthetic performance was associated with reduced carbon and nitrogen fluctuations and was accompanied by numerically greater root and stem biomass in the 2024 terminal shoots. Although fertilization effects were generally weak and transient, GSSG elicited notable responses, suggesting that the immediate enhancement of photosynthesis underlies its impact. However, its antioxidant properties under stressful conditions warrant further investigation. Full article

Straw return improves paddy soil quality and nutrient cycling, but its combined effects with nitrogen application on extracellular enzyme activities and greenhouse gas emissions in cold-region paddies remain unclear. A field experiment was conducted in Northeast China under full straw return (8.8 t ha⁻¹) with six nitrogen rates (0, 110, 120, 130, 140, and 150 kg ha⁻¹); conventional nitrogen application without straw return (130 kg ha⁻¹) was the control (CK), while N0 distinguished straw input from nitrogen effects. Soil properties, extracellular enzyme activities, and CO₂, CH₄, and N₂O emissions were measured 20, 50, 80, 110, and 140 days after straw return. At 140 days, compared with CK, straw return increased the NH₄+-N and organic matter in the 0–15 cm soil layer by 41.75% and 28.69%, respectively, and reduced pH by 4.34%. Under N110–N150, straw return enhanced the carbon- and nitrogen-acquiring enzymes and oxidative enzymes by 15.88–162.23%. In particular, β-glucosidase, phenol oxidase, and peroxidase activities were significantly higher under N130–N140 than under CK. Compared with N150, N130–N140 maintained organic matter turnover without further increasing greenhouse gas emissions. Overall, under full straw incorporation in the Mollisol paddies of cool Northeast China, N130–N140 sustained high yield while balancing nutrient cycling, enzyme activity, and greenhouse gas mitigation. Full article

This paper presents a novel Multi-Scale Temporal Uncertainty-aware Hierarchical Adaptive Ensemble (MSTU-HAE) algorithm for intelligent ship emission monitoring and prediction in maritime environmental compliance applications. The maritime shipping industry contributes approximately 3% of global CO₂ emissions and significant amounts of nitrogen oxides and sulfur oxides, necessitating advanced predictive monitoring systems. The proposed MSTU-HAE algorithm integrates three key innovations: multi-scale temporal feature extraction using causal convolutions at short-term (5 samples), medium-term (20 samples), and long-term (60 samples) windows; gas-specific attention mechanisms that automatically weight temporal scales based on individual emission gas characteristics; and three-level hierarchical uncertainty quantification encompassing individual model uncertainty, ensemble disagreement, and regulatory compliance risk assessment. Experimental validation was conducted using emission data collected from a fishing vessel over 3 operational days (1732 original samples), augmented to 17,320 samples via controlled replication with noise injection to support model training. Rigorous temporal data splitting with 70%/15%/15% train/validation/test partitioning ensures no data leakage. Comparative analysis against six baseline methods (XGBoost, LSBoost, AdaBoost, Ridge Regression, Random Forest, and K-Nearest Neighbors) demonstrates that MSTU-HAE achieves superior average performance, with R² = 0.9670 and NSE = 0.9670 across all emission gases. This research contributes a robust, interpretable, and scalable prediction framework that advances the state of the art in maritime environmental monitoring through novel algorithmic innovations in temporal feature learning and uncertainty quantification. Full article

Rapid urbanization has intensified challenges regarding urban waterlogging and vehicle exhaust pollution. While permeable asphalt mixtures mitigate waterlogging and nano-TiO₂ offers photocatalytic exhaust degradation capabilities, the direct application of nano-TiO₂ is hindered by agglomeration and low photocatalytic efficiency. This study developed a composite modified nano-TiO₂ via metal ion doping and support treatment to enhance its performance in asphalt pavements. Specifically, nano-TiO₂ was doped with Fe³⁺, Ag⁺, and La³⁺ via the sol–gel method, and supported on activated carbon (AC) or Al₂O₃. The exhaust degradation performance was evaluated using a custom-built system, while dispersion properties were assessed via fluorescence microscopy and UV-Vis spectrophotometry. Furthermore, X-ray diffraction (XRD) and Fourier-transform infrared (FTIR) spectroscopy were conducted to investigate the microstructural mechanisms underlying the doping modification and support treatment. Photocatalytic permeable asphalt mixtures were prepared by partially replacing mineral powder with the composite modified nano-TiO₂ to validate exhaust degradation and pavement performance. The results indicated that metal doping substituted Ti⁴⁺ in the lattice, inducing defects and reducing crystallite size to boost photocatalytic activity. The optimal doping concentrations are determined to be 1.0% for Fe³⁺, 1.5% for Ag⁺, and 1.0% for La³⁺. Among these, Fe³⁺-doped nano-TiO₂ at 1.0% content exhibits superior exhaust degradation, achieving 46.7% efficiency for hydrocarbons (HC) and 33.5% for nitrogen oxides (NO). Regarding dispersion, while AC performs better at low support content, Al₂O₃ at 40% content provides superior dispersion properties by increasing active sites and surface hydroxyl groups. For photocatalytic permeable asphalt mixtures, replacing 40–50% of mineral filler with the composite modifier is recommended. The optimized mixture demonstrates superior exhaust degradation performance while maintaining the required high-temperature stability, low-temperature cracking resistance, water stability, and fatigue life. Specifically, compared to the control group, these indicators for the mixture with 50% of the mineral filler replaced by the composite modifier increases by 7.0%, 12.5%, 13.4%, and 22.9%, respectively. This study presents a viable technical solution for developing multifunctional asphalt mixtures with photocatalytic functionality as the core innovation and mechanical performance as the application baseline. Full article

Trypanosoma evansi (T. evansi) infection poses a significant health threat to equines. This study was aimed to assess the prevalence, risk factors, hematobiochemical alterations, and oxidative stress-mediated genotoxicity associated with equine trypanosomiasis in the Rahim Yar Khan District. This cross-sectional study was conducted on 384 equines from October 2024 to September 2025. Blood samples were collected for thin blood film microscopy and PCR assay using RoTat 1.2 primers. Hematological indices were analyzed with an automated hematology analyzer; serum biochemical parameters were quantified via standard assays. Oxidative stress markers, including malondialdehyde (MDA), catalase (CAT), superoxide dismutase (SOD), and reduced glutathione (GSH), were also measured. Genotoxicity was evaluated using the alkaline comet assay. Statistical analyses included the chi-square test, logistic regression, and independent t-tests. T. evansi was detected in 5.99% of samples by microscopy and 10.16% by PCR, with no significant association with species, age, or sex. Infected equines exhibited significant reductions in hemoglobin (5.4 ± 0.6 vs. 10.8 ± 0.5 g/dL; p < 0.0001), total serum protein (2.1 ± 0.3 vs. 5.8 ± 0.2 g/dL; p < 0.0001), albumin, and globulin, alongside elevated hepatic enzymes, blood urea nitrogen, and creatinine (all p < 0.01). Oxidative stress was confirmed by increased MDA (p < 0.0001) and decreased CAT activity (p < 0.001). Genotoxicity was significantly higher in infected animals (genetic damage index; 1.12 ± 0.08 vs. 0.40 ± 0.01; p < 0.01). This study provides the first integrated assessment of molecular epidemiology and oxidative stress-mediated genotoxicity in equines in this region, suggesting the pathogenic impact of the infection and targeted diagnostics for disease management strategies. Full article

Wetland ecosystems have been a central focus of ecological research for an quite some time. Nevertheless, the degradation of wetland riparian zones has markedly accelerated due to anthropogenic activities, climate change, and habitat heterogeneity. The objective of this paper is to investigate the differences in functional traits of riparian plants under changing wetland environments on a karst plateau, as well as to elucidate the adaptive strategies of wetland plants across different habitats. This study examines the Caohai Wetland located on the Guizhou karst plateau, selecting the leaves of four dominant plant species (Phragmites australis, Onopordum acanthium, Galium odoratum, Paspalum distichum) in the Caohai Wetland lakeshore zone and analyzes the influence of soil factors on the variation of plant functional traits within the wetland riparian zone. The results reveal that: (1) significant differences exist in the functional traits of dominant plants in the riparian zones of karst plateau wetlands, with complex interrelationships among these traits; (2) the coefficients of variation for magnesium (Mg) and calcium (Ca) in the soil are notably high (79.53% and 67.21%, respectively), whereas soil oxidation-reduction potential (ORP) exhibits the lowest coefficient of variation (4.36%)—furthermore, the convergent variation in specific leaf area (SLA) and leaf dry matter content (LDMC) directly reflects the strong environmental filtering imposed by this habitat—and (3) redundancy analysis (RDA) indicates that leaf length (LL), specific leaf area (SLA), leaf area (LA), and plant carbon content (PCC) are particularly sensitive to environmental changes, while soil calcium (Ca), total nitrogen (TN), water-dispersible clay (WDR), soil organic matter (SOM), soil moisture content (SPMC), and total potassium (TK) constitute the principal soil factors influencing plant adaptive strategies in karst plateau wetlands. In conclusion, this study demonstrates that adaptation to karst wetland habitats is mediated through trade-offs in the allocation of photosynthetic products and the regulation of carbon (C), nitrogen (N), and phosphorus (P) nutrient balances under calcium-enriched and phosphorus-limited conditions, thereby reflecting the response characteristics of functional traits in karst plateau wetland plants to environmental changes. Full article

In situ coagulation is regarded as the most effective measure in response to the frequent metal spills in China. Excessive coagulant is often used in pursuit of extremely high removal rates of contaminants. Yet the secondary ecological impact of the iron-containing coagulation flocs left on the river sediments after emergency response is still unclear. In the current study, we investigated the impact of flocs derived from three different iron-based coagulants, polymeric ferric sulfate (PFS), polymeric ferric chloride (PFC), and ferric chloride (FeCl₃), on microbial communities in sediment based on microcosm experiments. Metagenomics, quantitative PCR, and determination of ammonia oxidation potential were adopted to elucidate community shifts. The results indicate that the community structure and function of microorganisms in sediments have been affected, especially processes and species related to nitrogen cycling, and the effect was coagulant-specific. Flocs retrieved from FeCl₃ caused a more pronounced decline in diversity, shifts in community composition, and decreased potential ammonia oxidation. Ammonia-oxidizing archaea (AOA) was more sensitive to iron-containing flocs than ammonia-oxidizing bacteria (AOB), while PFS-flocs tended to reduce multiple genes involved in nitrate reduction. This indicates that the pre-polymerization of inorganic coagulants may be the primary factor leading to different microbial ecological effects. Sulfate, on the other hand, may affect specific biogeochemical processes due to its competition for electron donors. Our results confirmed that even without heavy metals as contaminants, coagulant flocs alone could present an effect on nitrogen cycling in sediments. The results will provide a scientific basis for environmental emergency decision-making: in emergency response to metal pollution incidents, the use of coagulants should be limited to only the necessary level. Full article

Background:Pinellia ternata is a major medicinal herb widely utilized in traditional medicine, but is sensitive to high temperature, which often triggers a severe “sprout tumble” phenomenon. Methods: To elucidate the molecular mechanisms of heat tolerance in P. ternata, we screened two contrasting germplasms: the heat-tolerant JBX1 and the heat-sensitive XBX4. In the present study, a combined analysis of physiology, transcriptome, and metabolome was performed on JBX1 and XBX4 under heat stress at 40 °C. Results: JBX1 exhibited significantly greater leaf thickness, higher basal chlorophyll content, more stable antioxidant enzyme activities, and lower oxidative damage than XBX4 under heat stress. Transcriptomically, JBX1 maintained elevated basal expression of genes encoding key enzymes in carbon fixation, amino acid metabolism, and phenylpropanoid biosynthesis, as well as those encoding heat shock transcription factors (HSFs), heat shock proteins (HSPs), and the thermosensor Thermo-With ABA-Response 1 (TWA1). Metabolomically, JBX1 accumulated higher levels of key primary metabolites, antioxidants, and protective phenylpropanoids under both control and heat conditions. Notably, a “polarity reversal” emerged in nitrogen metabolism, where core amino acids accumulated in JBX1 but were depleted in XBX4. Integrated analysis revealed a more coordinated gene–metabolite network in JBX1 involving the phenylpropanoid, ATP-binding cassette (ABC) transporter, and glutathione pathways. Conclusions: Our findings demonstrate that JBX1 possessed stronger basal thermotolerance, which is derived from coordinated establishment of higher constitutive metabolic reserves and efficient dynamic metabolic reprogramming. This study provides insights into the molecular mechanisms of heat stress in P. ternata. Full article

Deammonification, which is based on partial nitritation and anammox (PN/A), is a well-established sidestream treatment for nitrogen removal. However, transferring deammonification to mainstream wastewater treatment remains challenging due to low temperatures, the need to retain slow-growing anammox bacteria (AnAOB), and their competition for nitrite with nitrite-oxidizing bacteria (NOB) and heterotrophic denitrifiers. This work investigates cubic polyurethane foam carriers to promote growth and retention of AnAOB. A moving bed biofilm reactor (MBBR) and an integrated fixed-film activated sludge (IFAS) reactor were compared over a three-year experimental period at lab-scale. The feasibility of the biofilm carriers for deammonification was first evaluated under sidestream conditions, followed by a stepwise transition to mainstream operational conditions. The impact of operational parameters, including dissolved oxygen concentration, pH value, and aeration strategy, was evaluated with respect to the activity of aerobic ammonium-oxidizing bacteria (AOB), NOB, and AnAOB, as well as nitrogen removal rates. Deammonification reached nitrogen removal rates of 0.04–0.12 kg N m⁻³ d⁻¹ (IFAS reactor) and 0.02–0.28 kg N m⁻³ d⁻¹ (MBBR) at subphases with reactor bulk concentrations above 60 mg NH₄-N L⁻¹. Highest nitrogen removal degrees of 77 ± 6% (IFAS) and 76 ± 5% (MBBR) were achieved at reactor bulk concentrations of 96 mg NH₄ L⁻¹ and 97 mg NH₄ L⁻¹, respectively. Lower concentrations triggered NOB activity in both reactors, leading to an increase in nitrate concentration up to 22 mg NO₃-N L⁻¹. AOB and AnAOB activities were on average 6-fold higher on the carriers compared to suspended biomass throughout all experimental phases, demonstrating the feasibility of using cubic polyurethane foam carriers for deammonification. This was also confirmed by fluorescence in-situ hybridization (FISH) measurements. Median nitrogen removal rates over all experimental phases of 0.07 kg N m⁻³ d⁻¹ for the IFAS reactor and 0.05 kg N m⁻³ d⁻¹ for the MBBR were achieved, which are comparable to conventional activated sludge systems performing nitrogen removal via nitrification–denitrification. While at lower nitrogen concentrations, the IFAS reactor yielded superior nitrogen removal rates, peak nitrogen removal rates of 0.28 kg N m⁻³ d⁻¹ were measured in the MBBR configuration. However, controlling NOB activity at lower temperatures and concentrations remains a challenge in MBBR and IFAS configurations. In our study, in the IFAS reactor NOB activities were visible on fewer days than in MBBR. At mainstream-like conditions, higher nitrogen removal rates of IFAS (0.09–0.12 kg N m⁻³ d⁻¹) were achieved compared to the MBBR (0.06–0.09 kg N m⁻³ d⁻¹). This demonstrates the advantage of the IFAS reactor in treating mainstream wastewater via deammonification. As an autotrophic nitrogen removal process, the implementation of deammonification in the mainstream of municipal wastewater treatment plants enables enhanced recovery of biogas from sewage organic matter. The latter would otherwise be consumed during the conventional nitrification-denitrification pathway. Consequently, the overall energy balance for wastewater treatment can be improved, contributing to a more environmentally sustainable process. Full article

The synthesis of nitrogen-containing heterocycles remains a subject of significant interest due to their applications in medicinal chemistry and materials science. This paper describes the preparation of imidazo[1,2-a]pyridine using a catalytic system consisting of the deep eutectic solvent (DES) choline chloride (ChCl)–tartaric acid (1:2) and I₂ by reaction between 2-aminopyridines and chalcones (1,3-diphenylprop-2-en-1-ones). The proposed mechanism suggests the activation of the chalcone carbonyl by the DES, enhancing the polarization of the conjugated system which suffers electrophilic addition by I₂ to the C=C bond. The resulting intermediate undergoes a nucleophilic attack by 2-aminopyridine followed by cyclization and iodine-promoted oxidation and aromatization to yield the corresponding imidazo[1,2-a]pyridine products. The role of the DES is crucial, as it facilitates carbonyl activation through hydrogen bond interactions, stabilizes reactive intermediates, and promotes protonation–deprotonation steps, thereby eliminating the need for metal catalysts or toxic organic solvents. Theoretical calculations at the PM6 level of theory suggest that the DES acts as a catalyst in this reaction, due to the nature of its components enabling the development of more sustainable synthetic strategies. Full article

The primary productivity of phytoplankton (PP_eu) is critical to the carbon cycle in aquatic ecosystems. However, in complex lakes covered by ice, the estimation of PP_eu using remote sensing techniques is constrained. To address this limitation, this study developed an estimation model for ice-covered PP_eu by incorporating optical parameters such as the ice surface refractive index and the extinction coefficient of the ice layer into the vertical generalized production model (VGPM). This approach overcomes the challenges associated with remote sensing-based estimation of PP_eu during ice-covered periods. The results indicate that the annual carbon sequestration of the WLSHL is 1.72 × 10⁴ t C, with an average annual PP_eu of 316.96 mg C·m⁻²·d⁻¹. In addition to the indicators that are directly involved in the estimation of PP_eu, the environmental factors that affect PP_eu include water temperature (WT), ice thickness (IT), snow, water depth (D), total dissolved solids (TDSs), salinity (S), ammonia nitrogen (NH₄⁺-N), nitrate nitrogen (NO₃⁻-N), and oxidation–reduction potential (ORP). The PP_eu in the ice period is found to be only 17% lower than that in the ice-free period. However, the PP_eu during the ice period is considerably higher than that during the ice + snow period. The findings indicate that the impact of freezing on PP_eu during the winter is relatively limited, whereas the influence of snowfall is more pronounced. In order to mitigate the elevated PP_eu and the occurrence of algal blooms during the summer, the intensity of underwater radiation can be regulated on a periodic basis. To optimize the function of the carbon sink in winter lakes, the PP_eu can be enhanced through initiatives such as water replenishment prior to freezing and snow removal following freezing. Full article