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# 所有论文

301. 题目: Formation characteristics of disinfection byproducts from four different algal organic matter during chlorination and chloramination

Algal organic matter (AOM) has become an important precursor of disinfection byproducts (DBPs) in multiple drinking water sources. In this study, the formation of DBPs during chlorination and chloramination of AOMs from four algal species (Microcystis aeruginosa, Chlorella vulgaris, Scenedesmus obliquus, and Cyclotella sp.) under different conditions (disinfectant doses 4.0–8.0 mg/L as Cl2, pH 6.0–8.0, and bromide 0–1.0 mg/L) were simultaneously investigated. Some common and specific characteristics of DBP formation have also been identified. The yields of total DBPs from the four AOMs were 3.28 × 102–6.00 × 102 and 1.97 × 102–3.70 × 102 nmol/mg C during chlorination and chloramination, respectively. The proportions of haloacetic acids (HAAs) in total DBPs were approximately ≥50%. Increasing disinfectant doses or pH only enhanced the yields of trihalomethanes (THMs) during chlorination but enhanced the yields of THMs, HAAs and dihaloacetonitriles (DHANs) during chloramination. Increasing bromide concentrations enhanced THM yields but decreased HAA yields during chlorination and chloramination, in addition to the shift from chlorinated DBPs to brominated DBPs. The DHAN yields of the four AOMs slightly decreased with bromide levels during chlorination, whereas different AOMs showed different trends with bromide levels during chloramination. During chlorination, C. vulgaris and S. obliquus AOMs generated higher THM and DHAN yields (at 4.0–5.0 mg/L as Cl2) than the other AOMs. During chloramination, M. aeruginosa AOM generated higher THM and HAA yields than the other AOMs (at 0.1 mg/L bromide). Cyclotella sp. AOM had the highest THM-bromine substitution factors during chlorination and the highest DHAN-bromine substitution factors during both chlorination and chloramination (at 0.1 mg/L bromide).

302. 题目: Influence of soil physical and chemical properties on mechanical characteristics under different cultivation durations with Mollisols

The degree of soil compaction is affected not only by the agricultural machinery but also by the soil physical, chemical, and mechanical properties. We hypothesized that the changes in the soil physical (clay content) and chemical properties (soil organic matter, SOM) due to long-term tillage operations would cause corresponding variations in the soil mechanics properties. The in-situ undisturbed soil samples were firstly adopted to detect soil properties as affected by long-term conventional tillage of Mollisol (black soil), and explore the relationship between soil physico-chemical properties and mechanical properties with 4 different cultivation duration croplands (0, 17, 30, and 40 yr). Then, artificial modified soil samples were further used to verify this relationship and confirm the predominate factor influencing compression-rebound behavior at 3 levels of SOM and clay contents, respectively, at 2 levels of gravimetric water contents. The compression index (Cc) and rebound index (Cr) were determined using a fast oedometer test. We found that with cultivation duration extending, the clay content and soil bulk density increased, while the SOM, Cc and Cr gradually decreased. The laboratory simulation tests also showed that the compressibility was higher when SOM or clay content was higher; while the soil resilient capacity was lower when the SOM was lower or clay content was higher. In conclusion, the decrease of SOM and the increase of clay content due to long-term cultivation could increase the risk of soil compaction and weaken its recovery capacity. SOM is predominant in influencing the soil mechanical properties relative to clay content. Maintaining and/or increasing SOM may improve the mechanical properties of arable Mollisols.

303. 题目: An investigation of the effects of humic acid on soil erosion and loss of phosphorus from soil to runoff: Experiment and modeling

Phosphorus (P) transport from soil to runoff is affected by the chemical adsorption of P by organic matter, or clay minerals. However, little information is available on the relative effects of different clay minerals on P adsorption in the presence, or absence of humic acid (HA). To achieve this objective, a rainfall erosion experiment was carried out in a cylindrical glass container with a basal area of 45 cm2. The experiment used four soil mixtures, namely kaolinite mixed soil (KMS), montmorillonite mixed soil (MMS), kaolinite mixed soil treated with HA (KMS-HA), and montmorillonite mixed soil treated with HA (MMS-HA), to analyze the influence of HA on soil erosion and loss of P. The experimental results showed that the cumulative loss of clay was highly significantly (p < 0.01) correlated with HA. The total loss of clay from KMS-HA and MMS-HA was five times and 1.7 times that from KMS and MMS, respectively. The results of the experiments showed that the addition of HA had a significant (p < 0.05) impact on the loss of soluble phosphorus (SP), and particulate phosphorus (PP) from the KMS, respectively, but did not significantly influence the SP and PP cumulative loss from the MMS. Temporal variation and inter-relationship of clay, SP, and PP in the soil matrix and runoff, as well as total organic carbon (TOC), were simulated using an integrated P transport model. The values for the coefficient of determination (R2, all greater than 0.73) indicated that the transport model performed well. The results of the experiments and simulations showed that there was competition between P and HA for adsorption onto clay particles, especially for kaolinite, resulting in the release of more SP and PP to runoff. This highlights why more attention needs to be given to HA in nutrient loss management.

304. 题目: Carbon saturation deficit and litter quality drive the stabilization of litter-derived C in mineral-associated organic matter in long-term no-till soil

Long-term no-till cropping systems can induce significant differences in the mineral associated organic matter (MAOM) saturation levels but little is known on the effect of MAOM saturation on “new” C stabilization from added litter in different fractions of soil organic matter (SOM). We assessed the effect of C saturation deficit (Csd) in the MAOM on C stabilization in different SOM fractions in the surface layers of a sandy clay loam Acrisol under five no-till cropping systems adopted over 36 years in a field experiment. The cropping systems with varying C inputs led to a range of C content and Csd in the MAOM (<20 µm) in a thin soil layer (0–5 cm). In each field plot with different Csd levels, 13C-labeled litter from shoot biomass of black oat (grass) and vetch (legume) was added at a rate equivalent to 4.5 Mg ha-1C in PVC collars. After 15-month field incubation, soil was sampled and physically fractionated. Higher C stabilization in MAOM was observed for legume than grass-derived C in the top 0–2.5 cm layer, but only for soils with higher C stabilization capacity. When litter-derived C stabilization in MAOM was limited by its previous C level close to saturation, C incorporation was greater in the intra- and inter-aggregate SOM fractions. Our findings revealed that Csd and litter quality affect C stabilization in surface soil layers of no-till soils, and when C stabilization in MAOM is low due to saturation of the MAOM fraction, the C accrual occurs preferentially in labile and intra-aggregate fractions in long-term no-till soils. Therefore, sustainable management practices that promote continuous and diversified C inputs involving legume cover crops are crucial to sustain C incorporation in relatively stable forms in long-term no-till soils.

305. 题目: Characteristics and controls of inorganic and organic phosphorus transformation during long-term paddy soil evolution

306. 题目: Drivers of the amount of organic carbon protected inside soil aggregates estimated by crushing: A meta-analysis

Given the importance of soil organic carbon (SOC) stocks and their dynamics in the regulation of climate change, understanding the mechanisms of SOC protection from decomposition is crucial. It is recognized that soil aggregates can provide effective protection of organic carbon from microbial decomposition. Currently, there is no systematic method for estimating the amount of protected carbon within aggregates. However, differences between CO2 emissions from incubation of intact versus crushed aggregates have been widely used as a proxy for SOC physical protection within aggregates. There is no global analysis on this type of experiment yet, nor on the drivers of the amount of SOC physically protected in soils. Using a meta-analysis including 165 pairs of observations from 22 studies encompassing a variety of ecosystems, climate and soil types, we investigated the crushing effects on cumulative carbon mineralization from laboratory incubation experiments. The aggregates were initially separated by either wet sieving or dry sieving before dry crushing. Our results indicated that aggregate crushing led on average to +31 % stimulation of carbon mineralization compared with intact aggregates, which represented 0.65 to 1.01 % of total SOC. This result suggests the mineralization of a previously protected pool of labile organic carbon. The linear regression analysis showed that the crushing effect on carbon mineralization depended on soil characteristics (carbon content, clay content and pH) as well as on aggregate size. Crushing aggregates stimulated carbon mineralization relative to control, up to +63 % in large aggregates (>10 mm), +38 % in large macro-aggregates (2–8 mm), +14 % in small macro-aggregates (0.25–2 mm) and +54 % in micro-aggregates (<0.25 mm). Within each aggregate size-class, the crushing effect depended on the crushing intensity. The destruction of aggregates to <0.05 mm size had a greater effect on carbon mineralization (+130–133 %) than the destruction of aggregates to >2 mm (+3 to 40 %), < 2 mm (+58 to 62 %) and < 0.25 mm (+32 to 62 %) sizes regardless of the initial aggregate size. These results suggest that macroaggregates (>0.25 mm) are less protective than microaggregates (<0.25 mm). Our dataset also show that soil physicochemical characteristics and experimental conditions influenced more the amount of protected SOC than land use and management. Contrary to our expectations the crushing effect was not affected by tillage practices nor land use. Standardizing the experimental conditions of aggregate crushing and subsequent incubation is needed to assess and compare the amount of physically protected SOC in diverse soils, and then to better understand the processes and drivers of SOC protection inside aggregates.

307. 题目: Biochar changed the distribution of imidacloprid in a plant–soil–groundwater system

The use of biochar has increased, as its physicochemical properties reduce the adverse effects of pesticides. However, few studies have comprehensively investigated the effects of biochar on the distribution of pesticides in a plant–soil–groundwater system. In this study, a biochar produced from rice straw at 550 °C was chosen, and column experiments with five rated of biochar application (application rates = 0.0, 1.0, 2.0, 3.0, and 4.0% w/w for B0–B4, respectively) were conducted to investigate the capacity of biochar to immobilize imidacloprid (IMI) in soil, thereby decreasing its uptake by plants and leaching from soil into groundwater. Our results showed that IMI in plants, leached from soil, and detected in soil accounted for 3.78, 1.76, and 36.4% of the total IMI input, respectively, and the biochar treatments dramatically decreased the IMI distribution to 0.57, 0.11, and 13.4%, respectively. By contrast, the percentage of undetected IMI increased from 58.1% in the B0 treatment to an average of 86.0% in the biochar treatments. Biochar treatments increased IMI immobilization in soil, which could be related to the increased soil carbon content, surface area, cation exchange capacity. This study indicates that biochar with characters of high surface area and porosity can stabilize IMI and reduce its potential to harm plants and groundwater.

308. 题目: Biomass accumulation and water use efficiency of faba bean-ryegrass intercropping system on sandy soil amended with biochar under reduced irrigation regimes

Intercropping is advantageous for optimizing crop productivity and resources utilization efficiency compared to monocultures. Yet, the effects of water/fertilizer management on crop growth and water use efficiency (WUE) in intercropping systems composed of legumes and non-legumes remain largely elusive. Biochar, as a soil amendment, could increase soil water storage and crop yield, but its interaction with soil water deficit and response of WUE are ambiguous. We investigated the growth, biomass and WUE in faba bean-ryegrass intercropping system amended with 550 ℃-pyrolyzed wheat straw (WSBC) and 800 ℃-pyrolyzed cleaning residues biochar (CRBC) under different irrigation treatments. Compared to the no biochar controls, CRBC decreased aboveground biomass (FDM) and seed yield (FGY) of intercropped faba bean, despite improved soil water-holding capacity, leaf water potential (LWP) and leaf hydraulic conductance (Kl) of faba bean. In contrast, CRBC significantly increased ryegrass aboveground biomass (GDM), although reduced the total aboveground biomass (TDM) and WUE (WUEf+g) of faba bean-ryegrass mixtures. These effects were not evident under WSBC. Compared to full irrigation, deficit (DI) and partial root-zone drying (PRD) irrigation enhanced GDM and WUEf+g, but lowered LWP and Kl, FDM and FGY, and PWU (plant water consumption) and TDM. Despite lower maximum quantum yield of photosystem II, PRD outperformed DI in improving biomass and WUE. The principal component analysis showed that PWU rather than biomass contributed significantly to the enhanced WUEf+g under DI and particularly PRD. Moreover, reduced irrigation regimes limited photosynthetic capacity of faba bean by depressing apparent quantum yield and increasing light compensation point, yet biochar addition did not. It was concluded that biochar produced at high temperatures might not be conducive in improving WUE of faba ban-ryegrass intercropping. Instead, PRD could be a prospective option to offset the adverse effect of biochar on plant under water-scarcity conditions.

309. 题目: Organic matter composition and greenhouse gas production of thawing subsea permafrost in the Laptev Sea

Subsea permafrost represents a large carbon pool that might be or become a significant greenhouse gas source. Scarcity of observational data causes large uncertainties. We here use five 21-56 m long subsea permafrost cores from the Laptev Sea to constrain organic carbon (OC) storage and sources, degradation state and potential greenhouse gas production upon thaw. Grain sizes, optically-stimulated luminescence and biomarkers suggest deposition of aeolian silt and fluvial sand over 160 000 years, with dominant fluvial/alluvial deposition of forest- and tundra-derived organic matter. We estimate an annual thaw rate of 1.3 ± 0.6 kg OC m−2 in subsea permafrost in the area, nine-fold exceeding organic carbon thaw rates for terrestrial permafrost. During 20-month incubations, CH4 and CO2 production averaged 1.7 nmol and 2.4 µmol g−1 OC d−1, providing a baseline to assess the contribution of subsea permafrost to the high CH4 fluxes and strong ocean acidification observed in the region.

310. 题目: Livestock manure-derived hydrochar improved rice paddy soil nutrients as a cleaner soil conditioner in contrast to raw material

Hydrothermal carbonization (HTC) is a promising technology for resource disposal of livestock manure due to its advantages of high efficiency, low-energy consumption and no dehydration. Previous studies most focused on the characterization and applications in various fields of livestock manure-derived hydrochar (LMH). However, the effects of LMH as soil conditioner on agricultural soil nutrients, dissolved organic matter (DOM) changes and crop yields have not been clarified. The major factors affecting the yield of LMH after returning to the field are also seldom mentioned. In this study, a soil column experiment was conducted to explore the changes in soil basic fundamental soil characteristics, DOM and rice yield after returning cattle manure (CM) and cattle manure-derived hydrochar (CC180 and CC260) to the field on the premise of reducing inorganic fertilizer application. The results showed that CCs increased soil nutrient partly, including total phosphorus (by 6.8–18.9%), soil organic carbon (by 8.2%) and dissolved organic carbon (by 18.7%) compared to CM. Soil ammonium nitrogen and nitrate nitrogen concentrations of CCs decreased by 5.8–9.9% and 4.7–15.8% in comparison with CM. LMH increased the stability of phosphorus by increasing the content of calcium bound phosphorus in soil. Three-dimensional fluorescence spectra expressed that soil DOM contained humic-like acid substances (C1 and C2) and tyrosine-like substances (C4). The three substances content in soil DOM under LMH treatment were higher than that of CM by 15.8–85%. In addition, infrared spectra and two-dimensional correlation analysis showed the structure and evolution of functional groups in soil DOM, which indicated that high temperature could increase the hydrophobic and saturated substances in soil DOM. Furthermore, CCs had a more significant than CM in rice yield by 19.9–36.9%. The findings illustrated that LMH is more beneficial to agricultural soil as a soil conditioner to replace part of chemical fertilizer than CM.

311. 题目: Fe-loaded biochar facilitates simultaneous bisphenol A biodegradation and efficient nitrate reduction: Physicochemical properties and biological mechanism

The simultaneous removal of nitrate and bisphenol A (BPA), two highly concerning contaminants in fluvial systems, is limited due to the low activity of the denitrifying community and poor degradability of BPA. Iron-loaded biochars (FeBCs) are efficient in promoting electron transfer efficiency and accelerating redox active processes, e.g., nitrate reduction and pollutant degradation. Nevertheless, the physicochemical properties of FeBCs and their potential strengthening mechanism during simultaneous removal of nitrate and BPA from aquatic systems are largely unknown. This study explored the potential of FeBCs to accelerate the simultaneous removal of nitrate and BPA. The FeBCs were prepared at 300–700 °C, with a BET surface area that increased from 10.78 to 207.97 m2 g−1 and oxygen content that decreased from 12.16% to 3.89%. Maximum nitrate and BPA removal of 99.0% and 74.1%, respectively, was achieved when the biochar was pyrolyzed at 500 °C (FeBC5). FeBC5 increased the levels of nicotinamide adenine dinucleotide (NADH), 5′-adenylate triphosphate (ATP), and electron transport system activity (ETSA) of the microbes, which were 485.50%, 371.88%, and 68.85% higher than the control values. After adding 0.05 g L−1 FeBC, the denitrifying enzyme activity and the level of nitrate-reducing genes increased by 48.22% and 45.6% respectively, and the genera responsible for denitrification and BPA degradation were increased by 5.56% and 33.33%, respectively. The BPA degradation pathway analysis suggested that the enhanced biotransformation of BPA resulted from co-metabolic degradation by denitrifying bacteria. The ferric-containing functional groups and their types were significantly correlated with nitrate-reducing enzymes and metabolic activities, facilitating the simultaneous removal of nitrate and BPA.

312. 题目: State-of-the-art of research progress on adsorptive removal of fluoride-contaminated water environments using biochar-based materials: Practical feasibility through reusability and column transport studies

Fluoride (${\text{F}}^{-}$) is one of the essential elements found in soil and water released from geogenic sources and several anthropogenic activities. Fluoride causes fluorosis, dental and skeletal growth problems, teeth mottling, and neurological damage due to prolonged consumption, affecting millions worldwide. Adsorption is an extensively implemented technique in water and wastewater treatment for fluoride, with significant potential due to efficiency, cost-effectiveness, ease of operation, and reusability. This review highlights the current state of knowledge for fluoride adsorption using biochar-based materials and the limitations of biochar for fluoride-contaminated groundwater and industrial wastewater treatment. Biochar materials have shown significant adsorption capacities for fluoride under the influence of low pH, biochar dose, initial concentration, temperature, and co-existing ions. Modified biochar possesses various functional groups (–OH, –CC, –C–O, –CONH, –C–OH, X–OH), in which enhanced hydroxyl (–OH) groups onto the surface plays a significant role in fluoride adsorption via electrostatic attraction and ion exchange. Regeneration and reusability of biochar sorbents need to be performed to a greater extent to improve removal efficiency and reusability in field conditions. Furthermore, the present investigation identifies the limitations of biochar materials in treating fluoride-contaminated drinking groundwater and industrial effluents. Since fluoride removal using biochar-based materials at an industrial scale for understanding the practical feasibility is yet to be documented, thus the review work recommended the potential feasibility of biochar-based materials in column studies that can be worth research on fluoride remediation in the future.

313. 题目: Wheat straw- and maize straw-derived biochar effects on the soil cadmium fractions and bioaccumulation in the wheat–maize rotation system

Wheat–maize rotation is one of the most popular systems and successful intensification cropping systems in Northern China, while soils in some of this area are contaminated by cadmium (Cd). However, few studies have performed experiments on the reduction of Cd accumulation in the wheat–maize rotation system. In this study, wheat- and maize-derived biochars are applied to the Cd-contaminated soil to reduce the Cd accumulation in the wheat and maize plants. The results showed that soil biochar applications can significantly decrease DTPA-extracted Cd concentrations by 12.7–26.0% and 13.1–20.5% by wheat- and maize-derived biochars, respectively. Sequential extractions showed that biochar applications significantly reduced the Cd mobility and bioavailability in soils and changed the exchangeable and carbonate-bound fractions of Cd to organic material-bound and residual fractions. The biochar applications increased the plant growth, yield, and quality of both wheat and maize, especially a significant increase in high dosages. The biochar applications also improved the antioxidant enzyme activities and reduced the reduction of MDA in both wheat and maize roots. The Cd concentrations in wheat grains were reduced by 38.1–91.5% and 65.9–80%, and maize grain Cd concentrations were reduced by 20.9–54.2% and 30.8–44% by wheat- and maize-derived biochar applications, respectively, and the Cd concentrations in the root, stem, and leaf were also significantly reduced. The wheat-derived biochar was more effective on the Cd reduction in soil bioavailable fractions and Cd accumulation in crop plants.

314. 题目: Soil moisture effects on predictive VNIR and MIR modeling of soil organic carbon and clay content

Portable visible to near-infrared (VNIR) and mid-infrared (MIR) soil spectroscopy holds great potential to support field applications in soil science and management by complementing conventional soil analytical methods. Under field conditions, however, soil moisture can critically affect the quality of reflectance measurements. In this study, we examined the effects of soil moisture on VNIR and MIR soil spectra and how its magnitude and variation impact the accuracy and robustness of predictive spectral models. We carried out a systematic re-wetting experiment on two soil datasets of different scale and origin that were measured at four gravimetric moisture levels (air-dried, 5 %, 10 %, 15 %) with portable VNIR and MIR instruments. The spectral data of each moisture class, as well as randomized combinations of different moisture contents, were then used to calibrate VNIR, MIR and combined PLSR models to estimate soil organic carbon (SOC) and clay content, where combined models included spectra concatenation (VNMIR) and model output average (MOA). The overall shape of MIR spectra was more significantly distorted by soil moisture than VNIR spectra, while the general impact of soil water content in both spectral domains was texture-dependent. In terms of predictive accuracy, MIR models were generally superior for air-dried sample material, while VNIR models fared better for uniformly moist samples. With increasing soil moisture variability, comparative estimation accuracies between individual VNIR and MIR models were dependent on the underlying dataset. VNMIR and MOA models proved beneficial and yielded the most accurate and robust predictions for SOC and clay content when soil moisture was variable, irrespective of the considered dataset (regional dataset: RMSESOC = 0.22–0.27 %, RMSECLAY = 2.67–3.14 %; field dataset: RMSESOC = 0.09–0.11 %, RMSECLAY = 0.87–1.15 %). Predictive mechanisms, as evaluated by variable importance in the projection (VIP) of PLSR models, changed substantially with variation in soil water content, especially in the MIR, where important absorption bands for SOC and clay minerals could be heavily attenuated or completely masked. Our study highlights the advantages of employing both VNIR and MIR instruments for spectral data collection on soils in field condition and the potential of integrating VNIR and MIR spectra collected at different soil moisture levels into soil spectral libraries.

315. 题目: Development of natural rubber-bamboo biochar composites for vibration and noise control applications

The present study focuses on the utilization of bamboo biochar (BB) as a filler in natural rubber (NR) composites. This work is the first attempt to investigate the influence of BB loading on the vibration damping and acoustical properties of NR composites. NR-BB composites were prepared according to the ASTM D3182-21a standard. Vibration damping and acoustical properties were examined using the Obrest beam (ASTM E756-05) and four microphone impedance tube (ASTM E2611-19) methods. Noteworthy, the vibration damping ratio or system loss factor (ξ) obtained maximum for the fourth mode of vibration {(NR- ξ = 33.19), NR/10BB- ξ = 17.46, and NR/20BB- ξ = 13.50) in the free layer damping (FLD) configurations. However, the sound transmission loss (STL) was enhanced by 8% and 11% compared to NR composites upon adding 10 and 20 phr of BB, respectively. In addition to vibration damping and STL, the loading of BB in the NR matrix positively influenced physical, mechanical, and thermal properties.

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316. 题目: Biochar application differentially affects soil micro-, meso-macro-fauna and plant productivity within a nature restoration grassland

Biochar is proposed as an option to sequester carbon (C) in soils and promote other soil-based ecosystem services. However, its impact on soil biota from micro to macroscale remains poorly understood. We investigated biochar effects on the soil biota across the soil food web, on plant community composition and on biomass production. We conducted a field experiment in a nature restoration grassland testing four treatments: two biochar types (herbaceous feedstock pyrolyzed at 400 °C or 600 °C – hereafter B400 and B600), and a positive (i.e. unpyrolysed biochar feedstock, hereafter Hay) and negative (no addition) control. Responses of plants and soil biota were evaluated one and three years after establishing the treatments.

Soil pH and K concentrations increased significantly in the B600 treatment. Mite abundances were significantly higher in B400 whereas nematode abundances were highest in Hay (1st year) and lowest in B400 (3rd year). Other soil fauna groups (enchytraeids and earthworms) varied more between years than between treatments. Legume cover increased significantly in the biochar treatments but this effect was transient. Legumes, grasses and primary productivity also showed a statistically significant Treatment x Year interaction due to transitory effects that were no longer present by the 3rd year.

Our results suggest that biochar produced from meadow cuttings and applied at the 10 t/ha rate cause transitory impacts on soil biota abundance and plant communities over the 3-year timeframe used for this experiment. Therefore, this type of biochar could potentially be used for soil carbon sequestration, with minimal impacts on soil biota abundance or diversity, within the groups studied here, or plant biodiversity and productivity. Further research is required to investigate the longer-term impacts of this potential soil C storage sink.

317. 题目: Co-application of biochar and pyroligneous acid improved peanut production and nutritional quality in a coastal soil

Coastal land is one of important marginal land types that have been considered as a potential reverse land source to alleviate the shortage of cultivated land. Biochar and pyroligneous acid have attracted much attention because of their good performance in improving the quality of infertile soil. However, the effect of co-application of biochar and pyroligneous acid on peanut production in coastal soil is poorly studied. In this work, a green-house experiment was conducted to compare the effects of individual and combined application of biochar (BC) and pyroligneous acid (PA) on the peanut yield and peanut kernel nutritional quality in a coastal soil, as well as soil properties, and soil microbiome. Compared with the individual application of BC or PA, the co-application of BC and PA dramatically increased peanut pod yield and amino acid contents. The ameliorated soil properties (e.g., water holding capacity) and elevated soil available nutrients (e.g., N, K and P) resulting from the co-application of BC and PA may contribute to the enhanced production of peanuts. High-throughput sequencing showed that both bacterial and fungal communities were altered regardless of individual or co-application, and co-occurrence network of bacterial community was significantly enhanced by the co-application of BC and PA. The abundances of soil beneficial bacteria (e.g. Arthrobacter, Blastococcus and Sphingomonas) and beneficial fungi (Humicola and Chaetomium) were enhanced by the co-application of BC and PA. This study demonstrates that co-application of BC and PA is a potential strategy to reclaim coastal soil for peanut cultivation.

318. 题目: In-situ growth of bimetallic FeCo-MOF on magnetic biochar for enhanced clearance of tetracycline and fruit preservation

319. 题目: Effects of biochar on the dynamic immobilization of Cd and Cu and rice accumulation in soils with different acidity levels

The aim of this study was to investigate the effect of biochar on Cd and Cu immobilization and bioavailability in soils with different acidity levels. Four dosages (0, 20, 40 and 60 g kg−1; namely CK, C1, C2 and C3) of biochar produced from rice straw were applied into the soils with four acidity levels (pH 4.5, 5.0, 5.5 and 6.0; namely L1, L2, L3 and L4), the uptake and transport of Cd and Cu by rice and metal speciation dynamics in soil were investigated through the two-year pot experiment. The soil pH and organic matter under all the four acidity levels were significantly increased during the rice maturity stage in the second year after biochar application. Biochar mainly promoted the formation of oxidizable Cd, followed by reducible Cd, and decreased residual Cd content (except for the first-year in the jointing period) during the two consecutive years of rice growth. Biochar reduced the acid extractable Cu content (especially in L2 and L3), increased the oxidizable Cu content, and interconverted Cu between reducible and residual status. The content of Cd in different rice organs were reduced by biochar, and compared with CK, the two-year average reduction in brown rice was 38.12%, 58.07%, 50.99% and 36.45% under L1, L2, L3 and L4. The reduction effect of Cu content in brown rice by biochar was mainly reflected in the second year, which decreased by 17.52%, 20.17%, 20.63% and 9.74% respectively under the four acidity levels. Rice straw biochar can be used for Cd pollution control of rice grain in paddy soil with varied acidity levels. However, further studies are needed on how biochar promotes Cu transport from rice root to shoot.

320. 题目: Large herbivores on permafrost— a pilot study of grazing impacts on permafrost soil carbon storage in northeastern Siberia

The risk of carbon emissions from permafrost is linked to an increase in ground temperature and thus in particular to thermal insulation by vegetation, soil layers and snow cover. Ground insulation can be influenced by the presence of large herbivores browsing for food in both winter and summer. In this study, we examine the potential impact of large herbivore presence on the soil carbon storage in a thermokarst landscape in northeastern Siberia. Our aim in this pilot study is to conduct a first analysis on whether intensive large herbivore grazing may slow or even reverse permafrost thaw by affecting thermal insulation through modifying ground cover properties. As permafrost soil temperatures are important for organic matter decomposition, we hypothesize that herbivory disturbances lead to differences in ground-stored carbon. Therefore, we analyzed five sites with a total of three different herbivore grazing intensities on two landscape forms (drained thermokarst basin, Yedoma upland) in Pleistocene Park near Chersky. We measured maximum thaw depth, total organic carbon content, δ13C isotopes, carbon-nitrogen ratios, and sediment grain-size composition as well as ice and water content for each site. We found the thaw depth to be shallower and carbon storage to be higher in intensively grazed areas compared to extensively and non-grazed sites in the same thermokarst basin. First data show that intensive grazing leads to a more stable thermal ground regime and thus to increased carbon storage in the thermokarst deposits and active layer. However, the high carbon content found within the upper 20 cm on intensively grazed sites could also indicate higher carbon input rather than reduced decomposition, which requires further studies including investigations of the hydrology and general ground conditions existing prior to grazing introduction. We explain our findings by intensive animal trampling in winter and vegetation changes, which overcompensate summer ground warming. We conclude that grazing intensity—along with soil substrate and hydrologic conditions—might have a measurable influence on the carbon storage in permafrost soils. Hence the grazing effect should be further investigated for its potential as an actively manageable instrument to reduce net carbon emission from permafrost.

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