341. 题目: In the weeds: Aquatic plant biomarker sources to Arctic lake sediments
342. 题目: A Potential Peanut Shell Feedstock Pyrolyzed Biochar and Iron-Modified Peanut Shell Biochars for Heavy Metal Fixation in Acid Mine Drainage
343. 题目: Application of peanut shell biochar increases rice yield in saline-alkali paddy fields by regulating leaf ion concentrations and photosynthesis rate
Saline-alkali soil seriously restricts the crop’s photosynthesis rate and yield formation. Biochar addition could alleviate the adverse impacts of saline-alkali stress in crops. However, little information is available on the ionic accumulation and photosynthesis rate of rice in highly saline-alkali paddy fields. This study aimed to evaluated the influence of the peanut shell biochar on leaf ionic concentration, stress physiology indices, photosynthesis related parameters and rice yield in highly saline-alkali paddy field condition.
Field experiment was carried out using two nitrogen application rate treatments (0 and 225 kg N ha−1) and four biochar applied rate treatments (0%, 1.5%, 3.0% and 4.5% w/w). The field experiment was arranged in a complete randomized design with three replications.
The results show that peanut shell biochar significantly reduced the leaf Na+ concentration, Na+/K+ ratio, abscisic acid and malondialdehyde concentration of rice, while enhanced leaf K+ concentration, and improved leaf water status and relative electrical leakage in treatments both with or without N fertilization. Furthermore, peanut shell biochar could provide beneficial effects on chlorophyll concentration, leaf N concentration, leaf area index, photosynthetic potential, stomatal conductance, and transpiration rates, which is of great benefit to the enhancement of leaf photosynthesis rate and net assimilation rate of rice population. In addition, the biomass, grain yield and harvested index were increased.
These results indicated that peanut shell biochar could effectively ameliorate saline–alkali stress and increase rice yield by regulating of leaf ionic concentration and improving leaf photosynthesis rate.
344. 题目: Impacts of MgO- and sepiolite-biochar composites on N-partitioning and dynamics of N-cycling bacteria in a soil-maize system: A field-based 15N-urea tracer study
Improving fertilizer-N retention and use efficiency (NUE) is imperative to mitigate the loss of reactive N into the environment. To reach additional improvements in N retention and NUE, we formulated MgO- and sepiolite-biochar nanocomposites with optimized N-retention capacity. The field-scale application of the modified biochars along with 15N-labeled urea (applied at 150 kg ha−1) was used to evaluate growth-stage-related N-partitioning, NUE, and N-recovery in a soil-maize (Zea mays L.) system. The effect of these biochars on growth-stage shifts in soil N-cycling enzymes, bacteria, and gene copies was reported for the first time. Results showed that during the 12-leaf stage, the MgO-biochar (MgOBF), sepiolite-biochar (SBF), and raw biochar (BF) amendments increased 15N-urea retention by 83.7 %, 26.7 %, and 33.0 %, respectively, than the sole fertilizer treatment (F). The improved 15N retention was attributed to the potential formation of an Mg-N complex, increased surface area, and cation exchange capacity (CEC) of the modified biochars particularly, in MgOBF, across maize growth stages compared to the raw biochar and SBF. Moreover, there was a simultaneous increase in the uptake of soil N across the plant growth stages in MgOBF and SBF compared to F and BF. At the physiological maturity (PM) stage, the total 15N uptake by maize was 17.1 % and 10.5 % higher in MgOBF and BF, respectively, compared to F. Moreover, the slow-release of the retained 15N and its increased uptake across maize growth stages increased NUE, biomass, and grain yield in MgOBF compared to other treatments. Hence, a total N recovery (soil + plant) of 90.8 % was recorded in MgOBF compared to 81.7 %, 67.9 %, and 67.8 % in the BF, SBF, and F treatments, respectively. A higher relative abundance of key N-cycling bacteria and their gene copies was associated with an increase in N-cycling enzymes in MgOBF and SBF at the PM stage, hence, promoting the slow-release of the retained N for plants' use. Our findings provide new insights into the applicability of modified biochars, especially, the MgO-modified biochar for improving fertilizer-N retention, NUE, and its recovery in the soil-plant system, while improving soil chemical properties.
345. 题目: Engineered biochar effects on soil physicochemical properties and biota communities: A critical review
Biochar can be effectively used in soil amendment, environmental remediation as well as carbon sequestration. However, some inherent characteristics of pristine biochars (PBCs) may limit their environmental applications. To improve the physicochemical properties of PBCs and their effects on soil amendment and pollution remediation, appropriate modification methods are needed. Engineered biochars (EBCs) inevitably have a series of effects on soil physicochemical properties and soil biota after being applied to the soil. Currently, most studies focus on the effects of PBCs on soil physicochemical properties and their amendment and remediation effects, while relatively limited studies are available on the impacts of EBCs on soil properties and biota communities. Due to the differences of biochars modified by various methods on soil physicochemical properties and biota communities, the impact mechanisms are different. For a better understanding of the recent advances in the effects of EBCs on soil physicochemical properties and biota communities, a systematic review is highly needed. In this review, the development of EBCs is firstly introduced, and the effects of EBCs on soil physicochemical properties and biota communities are then systematically explored. Finally, the suggestions and perspectives for future research on EBCs are put forward.
346. 题目: Evaluation of Preformed Monochloramine Reactivity with Processed Natural Organic Matter and Scaling Methodology Development for Concentrated Waters
347. 题目: Effects of Modified and Nitrogen-Enriched Biochars on Ammonia Emissions and Crop Yields Under a Field Environment
It has been demonstrated that biochar has a great potential to reduce volatilisations of ammonia (NH3) from fertilised agricultural soils. While there have been several laboratory studies to demonstrate the effects of biochar on gaseous NH3 emissions, there is hardly any data on the influence of biochar amendments on NH3 volatilisations from the soils under a field environment. Modifying biochar or enriching it with nitrogen (N) may maximise its capacity to abate gaseous NH3 emissions from the soil. Three biochars, i.e. SAB, HPB, and KHB modified through post-pyrolysis treatment with sulphuric acid, hydrogen peroxide, and potassium hydroxide, respectively as well as two biochars enriched with either molten urea (URB) or ammonium nitrate (ANB), were used alongside the pristine biochar (PRB) for comparisons. The quantity of gaseous NH3 evolved from each the biochar amendments including their effects on the growth and yield of the Chinese cabbage plus selected soil chemical properties were evaluated through a field experiment. The control experiment consisted of urea applied alone. In comparison with the control, PRB, KHB, HPB, SAB, URB, and ANB amendments abated NH3 volatilisations from the soil by 44.18%, 45.91%, 63.23%, 65.62%, 72.66%, and 76.71%, respectively. Additionally, PRB, SAB, KHB, HPB, ANB, and URB amendments increased Chinese cabbage yields by 138.5%, 172.0%, 117.3%, 181.1%, 194.0%, and 181.1%, respectively in comparison with the control. The strong linear relationship (r2 = 0.97) between cumulative NH3 emissions and nitrogen use efficiencies indicates that biochar-induced reductions in emissions of gaseous NH3 concomitantly increased the use-efficiencies of the applied N.
348. 题目: Production of BTX via Catalytic Fast Pyrolysis of Printed Circuit Boards and Waste Tires Using Hierarchical ZSM-5 Zeolites and Biochar
349. 题目: Carbon content, carbon fixation yield and dissolved organic carbon release from diverse marine nitrifiers
350. 题目: Deciphering the Fingerprint of Dissolved Organic Matter in the Soil Amended with Biodegradable and Conventional Microplastics Based on Optical and Molecular Signatures
351. 题目: Insight into the Mechanism of Humic Acid’s Dissolution Capacity for Lignin in the Biomass Substrates
352. 题目: How biogenic polymers control surfactant dynamics in the surface microlayer: insights from a coastal Baltic Sea study
353. 题目: Physically separated soil organic matter pools as indicators of carbon and nitrogen change under long-term fertilization in a Chinese Mollisol
Isolation and quantification of soil organic matter (SOM) pools under the influence of management practices is needed for assessing the changes in soil fertility. However, the knowledge on how the active, slow and passive pools of SOM respond to long-term fertilization is scarce. Therefore, the present study was designed to isolate the active, slow, and passive pools of soil organic matter through physical fractionation under long-term fertilization. The treatments included; inorganic fertilization (NPK) either alone or combined with a normal dose of manure (MNPK) or a high dose of manure (1.5MNPK) with an unfertilized control (CK) for comparison. The isolated pools were analyzed and compared for their sizes, SOC and TN storage and their contribution to total SOC and TN sequestration. The results revealed that the fertilization enhanced the active, slow and passive pools of SOC and TN and their storage under applied treatments was patterned as 1.5MNK > MNPK > NPK > CK. The highest SOC and TN storage was observed in the active pool, while, greater response to fertilization (in terms of response ratio) was associated with the slow pool. Results show that fertilization enhanced the proportion of SOC and TN stocks to bulk SOC and TN stocks in active and slow pools, while a diminishing trend was found for passive pools. Moreover, the highest response ratio was found for TN sequestration in each pool as compared to SOC, suggesting preferential accumulation of TN over SOC in the studied soil. Nevertheless, the highest SOC and TN storage took place in the active pool. The slow pool showed greater response to applied fertilizer, with the highest values being observed under 1.5MNPK. This study concluded that long-term manure + inorganic fertilization is crucial for enhancing C and N sequestration by altering the size and response of SOM pools.
354. 题目: Response of soil organic carbon fractions to legume incorporation into cropping system and the factors affecting it: A global meta-analysis
Recently, there has been increased advocacy for the adoption of rational cropping systems to increase soil organic carbon (SOC) levels and health and ensure food security. The intercropping and crop rotation of legumes with other crops is believed to improve soil environment and influence SOC dynamics. However, a comprehensive assessment of the effects of legume incorporation into cropping systems (LCS) on SOC fractions is still lacking. Therefore, this study aims to elucidate the effects of LCS on SOC fractions under different climatic conditions, soil properties, and agronomic practices, based on meta-analysis of 85 publications. LCS significantly increased the concentrations of microbial biomass carbon (MBC), dissolved organic carbon (DOC), particulate organic carbon, light fraction carbon (LFC), heavy fraction carbon, labile carbon pool, and recalcitrant carbon pool by 21.4 %, 7.2 %, 9.1 %, 29.6 %, 6.4 %, 7.1 %, and 7.9 %, respectively, compared with cropping systems without legume. LCS-induced increase in the contents of SOC fractions was stronger under relatively suitable climatic conditions (mean annual temperature > 15 °C, mean annual precipitation > 1000 mm, and aridity index (AI) > 0.65) and soils with more severe nutrient limitation (soil organic matter < 10 g kg−1, pH < 6.6, and subsoils). Specifically, AI was positively correlated with the response ratios of labile organic carbon fractions, whereas initial soil pH was negatively correlated with MBC, DOC, and LFC. Additionally, low nitrogen fertilizer application rates (< 120 kg ha−1) and intercropping favored an increase in SOC fractions under legume cultivation. Overall, these results provide insights into the ecological benefits of legumes and highlights the importance of developing site-specific strategies to effectively manage SOC dynamics under legume cultivation for sustainable agricultural practices.
355. 题目: Impact of compost methods on humification and heavy metal passivation during chicken manure composting
Livestock manure is one of the main sources of heavy metals (HMs) in agricultural soil. So, it is necessary to reduce its bioavailability before used as organic fertilizer. In this study, the passivation effect of HMs and the evolution of dissolved organic matter (DOM) during four composting processes were explored. Results showed that different composting methods had a great effect on HMs passivation rate and humification degree. HMs were released during the thermophilic phase, and were bound by resynthesized humus during the cooling period. The best passivation effect of HMs was found in FV + T treatment, the passivation rate of Cu, Zn, Cd and Pb reached 63.80%, 34.07%, 86.54% and 45.14%, respectively, then followed by the treatment of NV + T and SC. UV–Vis spectra and excitation-emission matrix (EEM) spectra indicated that humus precursors were produced during thermophilic phase and the accumulation of humus mainly occurred in cooling period. This study can be used as a theoretical support for the safe utilization livestock manure.
356. 题目: Effects of biological soil crusts on soil labile organic carbon of patchy alpine meadows in the Source Zone of the Yellow River, West China
Biological soil crusts (BSCs) play an important ecological role in the biogeochemical cycles, but there is limited knowledge about their effects on the composition of soil labile organic carbon (LOC) in the soil of patchy alpine meadow. In patchy alpine meadow with different altitudes, the different LOC compartments, vegetation, soil properties and C-hydrolase activity of active patches (with plateau pika), inactive patches (without plateau pika), restored patches, BSCs patches, and healthy alpine meadow were analyzed to assess the effects of BSCs on LOC. The key influence pathway of eco-environmental factors of LOC was determined by the structural equation model (SEM). The results showed that the BSCs at the altitude of 3570 m increased dissolved organic carbon (DOC), easily oxidized organic carbon (EOC) and microbial carbon (MBC) by 293%, 73% and 36%, respectively, compared with active patches in the 0–2 cm layer, which was significantly higher than those of inactive patches and recovered patches. There was no significant difference among DOC, EOC and MBC in different patches at the altitude of 4224 m. The MBC content of active patches decreased, but other patches and healthy alpine meadow showed a Λ- shaped change with altitude. The contents of soil total nitrogen and organic matter of BSCs patches were generally higher than those of active and inactive patches at three different altitudes. Structural equation model results showed that at the altitude of 3570 m, total nitrogen had a strong positive correlation with DOC, with a path coefficient of 0.677. There was a direct negative relationship between soil organic matter and DOC (path coefficient = −0.278) at the altitude of 4013 m. At the altitude of 4224 m, there was no direct correlation among soil nutrient, C-hydrolase activity, and soil LOC. Therefore, BSCs mainly promote the accumulation and recovery of LOC by increasing the soil total nitrogen content in different patches at different altitudes, which are beneficial to the restorations of LOC, total nitrogen and soil organic matter. Hence, they should be considered as key factors in the processes of restoring patchy alpine meadows.
357. 题目: Contribution of filtration and photocatalysis to DOM removal and fouling mechanism during in-situ UV-LED photocatalytic ceramic membrane process
The use of ceramic membranes and ultraviolet light-emitting diodes (UV-LEDs) has advanced the application of photocatalytic membrane for water treatment. We systematically evaluated the contribution of filtration and photocatalysis to dissolved organic matter (DOM) removal and fouling mechanism during in-situ UV-LED photocatalytic ceramic membrane filtration. The results showed that physical rejection primarily led to removal of 4–15 kDa molecules and photocatalysis further increased the removal of 1-4 kDa molecules, causing small sized microbial humic-like or protein-like materials in the permeate. In-situ UV-LED photocatalysis had an excellent effect on membrane fouling mitigation regardless of DOM sources. The dominant fouling mechanism changed from partial blockage to gel layer formation with increasing Ca2+ concentration but did not change with UV treatment. Correlation analysis revealed that the removal of 1-4 kDa molecules contributed to the mitigation of both reversible and irreversible fouling resistance, and the small molecules were the major cause of irreversible fouling resistance. Removal of 1–4 kDa terrestrial humic acid-like contributed to the pore blockage mechanism for synthetic water. Removal of 4-15 kDa protein-like materials was closely correlated to the pore blockage mechanism for real water. Trihalomethanes (THMs) and haloacetic acids (HAAs) formation potential (FP) were both significantly reduced after photocatalytic ceramic membrane process, but precursors of nitrogenous disinfection by-products (N-DBPs) with high toxicity were not removed by filtration or by photocatalysis, which deserves attention. Membrane rejection made higher contribution to better DBPFP control than photocatalysis. This study provides novel insights into the impact of UV-LED on DOM removal, DBPFP control and fouling mitigation, promoting the development of photocatalytic ceramic membrane filtration.
358. 题目: Best practice for upscaling soil organic carbon stocks in salt marshes
Calculating the amount of soil organic carbon (SOC) stored in coastal environments, including salt marshes, is needed to determine their role in mitigating the Climate Crisis. Several techniques exist to calculate the SOC content of a unit of land from the upscaling of soil cores. However, no comprehensive assessment has been made on the performance of commonly used SOC upscaling techniques until now. We measured the SOC content of soil cores gathered from two Scottish salt marshes. Two SOC values were used for upscaling; SOC content for a 1 m standardised depth (as recommended by the IPCC), and SOC content of the modern marsh deposit (identified in the stratigraphy as a transition from organic-rich (marsh) to mineral-rich (intertidal flat) soil. Twenty-two upscaling techniques were used (SOC content × area, interpolative, and regression-based extrapolative calculations). Leave-one-out cross-validation procedures and prediction interval widths were used to assess the accuracy of each technique. Digital Terrain Models and Normalized Difference Vegetation Indices were used as covariate surfaces in the regression models. We found that marsh-scale SOC stocks varied by as much as fifty-two times depending on which sampling depth and upscaling technique was used. The largest differences emerged when comparing SOC stocks upscaled from 1 m deep and modern marsh deposits. Using the IPCC recommended 1 m sampling depth inflated the SOC stocks of salt marshes, as intertidal flat environments were included in the calculation. Ensemble regression models from the weighted average of seven machine learning algorithm outputs produced the highest upscaling accuracies across marshes and sampling depths. Simple SOC content × area calculations produced marsh-scale SOC stocks that were comparable to stock values produced by more advanced ensemble regression models. However, regression models produced detailed maps of SOC distribution across a marsh, and the associated uncertainty in the SOC values. Our findings are broadly applicable for other environments where large-scale SOC stock assessments and uncertainty are needed.
359. 题目: Impact of biochar on anaerobic digestion: meta-analysis and economic evaluation
The growing global energy demand encourages the request for renewable sources, as biomethane from the anaerobic digestion (AD) of waste biomass. Biochar (BC) can effectively increase methane production when supplemented to AD, depending on BC physico-chemical properties. This study was developed in two phases. Firstly, a systematic meta-analysis of current literature was performed to correlate AD performance with BC properties, aiming to define their optimal range. The obtained results prove that BC enhances and accelerates biomethane production. Considering 408 experimental conditions of 76 studies in batch mode, biomethane yield and maximum production rate were significantly increased by BC addition. From the results of the subgroups meta-analysis, an optimal range of BC physico-chemical properties may be suggested as follows: high ash (≥ 20%) and low C contents (< 50%), high O/C molar ratios (≥ 0.3), high contents of O (≥ 20%) and N (≥ 0.6%), acidic pH (< 7.0), low surface area (< 10 m2 g-1). Secondly, an economic analysis aimed at assessing the economic profitability of BC addition to an existing AD plant suggest avoiding a dose above 0.45-0.76 gBC gVS-1, independently of the specific AD operating conditions. In conclusion, BC application in full-scale digesters is able to maximize biomethane production and economically feasible.
360. 题目: Biochar application as a soil potassium management strategy: A review
The established practices of intensive agriculture, combined with inadequate soil Κ replenishment by conventional inorganic fertilization, results in a negative environmental impact through the gradual exhaustion of different forms of K reserves in soils. Although biochar application as soil amendment has been established as an approach of integrated nutrient management, few works have focused on the impact of biochar application to soil K availability and crop uptake. This review provides an up-to-date analysis of the published literature, focusing on the impact of biochar in the availability of potassium in soil and crop growth. First, the effect of biomass type and pyrolysis temperature on potassium content of biochar was assessed. Second, the influence of biochar addition to the availability of potassium in soil and on potassium soil dynamics was examined. Finally, alternative methods for estimating available K in soils were proposed. The most promising biomasses in terms of potassium content were grape pomace, coffee husk and hazelnut husk however, these have not been widely utilized for biochar production. Higher pyrolysis temperatures (>500 °C) increase the total potassium content whereas lower temperatures increase the water-soluble and exchangeable potassium fractions. It was also determined that biochar has considerable potential for enhancing K availability through several distinct mechanisms which eventually lead directly or indirectly to increased K uptake by plants. Indirect mechanisms mainly include increased K retention capacity based on biochar properties such as high cation exchange capacity, porosity, and specific surface area, while the direct supply of K can be provided by K-rich biochar sources through purpose-made biochar production techniques. Research based on biochar applications for soil K fertility purposes is still at an early stage, therefore future work should focus on elucidating the mechanisms that define K retention and release processes through the complicated soil-biochar-plant system.