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1.
Inflamm Bowel Dis ; 2024 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-39419819

RESUMO

INTRODUCTION: We investigated relationships between disease activity measures and the gut microbiome in children with Crohn's disease (CD) and how these were confounded by gastrointestinal transit time. METHODS: Microbiome was profiled (16S rRNA sequencing) in feces from 196 children with CD. Sixty participants also provided samples after 18 months. Mural inflammation (Pediatric Inflammatory Crohn's Magnetic Resonance Enterography Index, PICMI), the simple endoscopic score for CD, and the weighted pediatric Crohn's disease activity index (wPCDAI) were assessed. Fecal calprotectin, plasma C-reactive protein (CRP), and fecal water content (FWC), a proxy of gastrointestinal transit time, were measured too. RESULTS: Microbiome α diversity, clustering, and differential taxa were related to disease status, but varied remarkably by disease activity measure used. The strongest relationships between microbiome and disease activity status were observed using wPCDAI; fewer or no relationships were seen using more objective measures like PICMI. Taxa predictive of disease activity status were dependent on the disease activity measure used with negligible overlap. Active disease was associated with more pathobionts (eg, Viellonella, Enterobacterales) and fewer fiber-fermenting organisms. The effect FWC had on microbiome superseded the effect of active disease for all disease activity measures, particularly with wPCDAI. Accounting for FWC, the differences in microbial signatures explained by disease activity status were attenuated or lost. CONCLUSIONS: In CD, microbiome signatures fluctuate depending on the measure used to assess disease severity; several of these signals might be secondary disease effects linked with changes in gut motility in active disease. PICMI appears to be less influenced when studying relationships between microbiome and mural inflammation in CD.


Microbiome signatures are related to Crohn's disease status but vary remarkably by disease activity measure used. The effect gut transit time has on microbiome supersedes and confounds the effect of active disease, particularly with the use of less objective disease activity measures.

2.
Anal Chim Acta ; 1329: 343188, 2024 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-39396278

RESUMO

BACKGROUND: There is an urgent need to replace fossil-based fuels and chemicals with bio-based, renewable alternatives. Water content is a critical parameter in these liquid products since water affects their quality and properties. However, currently existing methods for bio-oil water content determination have limitations and thus, there is a need to find methods that are versatile, work for a wide water content and sample consistency range repeatably and reliably and are safe for the user and the environment. RESULTS: In this research, a17O NMR spectroscopy protocol for water content determination of pyrolysis and hydrothermal liquefaction (HTL) liquids was developed and compared with the standard method Karl Fischer (KF) titration. The approach showed linearity over a wide concentration range, and the changes to the measurement parameters caused only minor effects to the results (≤0.8 percentage points) indicating robustness. The method is also accurate since the absolute differences between experimental and theoretical water contents varied from 0.08 % to 2.09 %. Additionally, the precision of the method, based on the relative standard deviations (RSD) of the three replicate measurements of pyrolysis and HTL samples, was good (RSD <1.82 %). The method was applied to samples containing 1-98 wt% water. Overall, the 17O NMR spectroscopy and KF titration results were well aligned with each other suggesting that the 17O NMR spectroscopy is a potential alternative for the conventional KF titration. SIGNIFICANCE: This is the first study on the use of 17O NMR spectroscopy protocol for water content quantification. The results indicate that the protocol is an accurate, linear, and precise technique for water content determination of a wide range of samples. Furthermore, the method does not require hazardous chemicals or calibration standards, and the sample preparation is straightforward. The non-destructiveness of the method also enables further studies on the sample, e.g. by 1H NMR spectroscopy.

3.
J Hazard Mater ; 480: 136053, 2024 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-39395391

RESUMO

The ecological risks of biodegradable microplastics (BMPs) to soil ecosystems have received increasing attention. This study investigates the impacts of polylactic acid microplastics (PLA-MPs) and polybutylene adipate terephthalate microplastics (PBAT-MPs) on soil properties of black soil (BS) and fluvo-aquic soil (FS) under three water conditions including dry (Dry), flooded (FL), and alternate wetting and drying (AWD). The results show that BMPs exhibited more evident aging under Dry and AWD conditions compared to FL condition. However, BMPs aging under FL condition induced more substantial changes in soil properties, especially dissolved organic carbon (DOC) concentrations, than under Dry and AWD conditions. BMPs also increased the humification degree of soil dissolved organic matter (DOM), particularly in BS. Metagenomic analysis of PBAT-MPs treatments showed different changes in microbial community structure depending on soil moisture. Under Dry conditions, PBAT-MPs enhance the ammonium-producing process of soil microbial communities. Genes related to N nitrification and benzene degradation were enriched under AWD conditions. In contrast, PBAT-MPs do not change the abundance of genes related to the N cycle under FL conditions but significantly reduce genes related to benzene degradation. This reduction in benzene degradation genes under FL condition might potentially slow down the degradation of PBAT-MPs, and could lead to temporary accumulation of benzene-related intermediates. These findings highlight the complex interactions between BMPs, soil properties, and microbial communities, emphasizing the need for comprehensive evaluations of BMPs' environmental impacts under varying soil water conditions.

4.
Sci Total Environ ; 954: 176740, 2024 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-39378952

RESUMO

Shortened multiday reaction experiments were conducted using the KIST chamber for atmospheric processes simulation (K-CAPS) to characterize the effects of ammonia (NH3) and relative humidity (RH) on the formation of secondary organic aerosols (SOA) due to photooxidation of a mixture of toluene and inorganic gases such as NOx, SO2, and NH3. UV lamps were repeatedly turned on for 3 h (daytime) and off for 6 h (nighttime), and precursors were injected to a reaction bag once (Multiday Initial injection, MI) or repeatedly (Multiday Cyclic injection, MC) to simulate high particulate matter episode due to foreign inflow episode and domestic stagnation episodes, respectively. As a result, the amount of SOA formed in the humid (RH 80 %) MI experiments with ammonia was approximately 1.1 times more than in the traditional single day experiment and approximately 1.6 times more than in the MC experiment, implying that aging processes including nighttime effects without additional emission of precursors during transport can produce more SOA as reactions progressed further under the experimental conditions of this study. The higher the initial RH, the more SOA was formed, with a slope increasing approximately 1.2 µg/m3 per unit RH, and the shorter run time required for SOA to increase to 30 µg/m3 (twice the WHO PM10 standard), with a slope decreasing approximately 0.3 h per unit RH, implying that more humid condition caused during long-range transport across the oceans is one of the possible reasons of high secondary aerosol formation. The SOA formation was reduced by approximately 60 % in the absence of ammonia, suggesting that ammonia reduction is needed to decrease not only secondary inorganic aerosols but also SOA. These results are useful to understand the major reason of high pollution of particulate matters by episode cases in urban areas.

5.
J Fish Biol ; 2024 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-39435493

RESUMO

Energy content has long been proposed as a fundamental, integrated, and reliable indicator of the condition of individuals as it reflects past bioenergetics and influences future life-history traits. There is a direct biochemical link between energy density and body composition described by four main compounds in fish (protein, lipid, ash, and water), with proteins and lipids being the sources of energy. If relationships between water content, or lipid content, and energy density have been well described in relative terms, the absolute mass variations in the proximate composition have been overlooked and thus their interpretation is often equivocal. In our study, based on a large and unique dataset on the proximate composition and energy density of anchovy (Engraulis encrasicolus) and sardine (Sardina pilchardus) from sampling in the Bay of Biscay and the English Channel, we aimed to better explain the patterns between water content and other proximate components or energy density, based on the dynamics of proteins, lipids, and water absolute masses. For the first time, we defined good, intermediate, and poor condition states in wild fish, based on water content, corresponding to the different dynamics of lipids and proteins in the metabolism of individuals. Anchovy and sardine exhibited remarkably similar patterns of variation in the compounds and in the limits between the condition states with respect to water content. Those patterns revealed that water mass remained constant for a given fish size whatever its condition state, and that variability in water content only resulted from the variation in lipid and protein masses. Furthermore, the differential dynamics of proteins and lipids, with only lipids mobilized in the good condition state, only proteins in the poor condition state, and both proteins and lipids in the intermediate condition state, elucidates the nonlinear pattern observed in the relationship between energy density and water content. Overall, our results highlight the importance of monitoring the intraspecific variations in water content to predict the proximate composition and energy content in small pelagic fish and better assess individual and population conditions in changing ecosystems as well as to better parameterize bioenergetic models.

6.
J Fungi (Basel) ; 10(10)2024 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-39452669

RESUMO

Truffles of the Tuber genus (Pezizales, Ascomycetes) are among the most valuable and expensive foods, but their shelf life is limited to 7-10 days when stored at 4 °C. Alternative preservation methods have been proposed to extend their shelf life, though they may alter certain quality parameters. Recently, a hypogeal display case equipped with an ultrasonic humidity system (HDC) was developed, extending the shelf life to 2-3 weeks, depending on the truffle species. This study assesses the efficacy of HDC in preserving Tuber melanosporum and Tuber borchii ascomata over 16 days, using quantitative magnetic resonance imaging (QMRI) to monitor water content and other parameters. Sixteen T. melanosporum and six T. borchii ascomata were stored at 4 °C in an HDC or a static fridge (SF) as controls. QMRI confirmed that T. borchii has a shorter shelf life than T. melanosporum under all conditions. HDC reduced the rate of shrinkage, water, and mass loss in both species. Additionally, the Apparent Diffusion Coefficient (ADC), longitudinal relaxation time (T1), and transverse relaxation time (T2), which reflect molecular changes, decreased more slowly in HDC than SF. QMRI proves useful for studying water-rich samples and assessing truffle preservation technologies. Further optimization of this method for industrial use is needed.

7.
Plant Physiol Biochem ; 217: 109200, 2024 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-39454536

RESUMO

Heavy metal contamination increases plant susceptibility to both biotic and abiotic stresses. However, the comprehensive impact of heavy metal pollution on plant hydraulics, which is crucial for plant productivity, and the interaction between heavy metal stress and environmental factors on plant health are not yet fully understood. In this study, we investigated the effects of cadmium exposure on plant-water relations and hydraulics of Solanum lycopersicum L., cultivar Piccadilly. Particular attention was given to leaf hydraulic conductance (KL) in response to cadmium pollution and dehydration. Cadmium exposure exhibited negligible impacts on tomato productivity but resulted in significant differences in pressure-volume derived traits. Leaves and roots of Cd-treated plants showed reduced wall stiffness compared to control samples. However, Cd-treated leaves had a less negative turgor loss point (Ψtlp), whereas Cd-treated roots exhibited more negative Ψtlp values due to lower osmotic potential at full turgor compared to control samples. Leaves and root cells of Cd-treated plants showed higher values of saturated water content compared to control plants, along with a distinct mineral profile between the two experimental groups. Despite similar leaf water potential thresholds for 50% and 80% loss of KL in control and cadmium-treated leaves, plants grown in cadmium-polluted soil showed higher leaf cell damages even under well watered conditions. This, in turn, affected the plant ability to recover from drought upon rehydration by compromising cell rehydration ability. Overall, the present findings suggest that under conditions of low water availability, cadmium pollution increases the risk of leaf hydraulic failure.

8.
Foods ; 13(20)2024 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-39456278

RESUMO

The grinding process is one of the key factors affecting the quality of glutinous rice flour (GRF). As an emerging grinding method, semidry grinding aims to solve the problems of the high yield of wastewater in traditional wet grinding and the high content of damaged starch in dry grinding, in which the water content has a great influence on the quality of GRF. However, semidry grinding has not yet been formally put into production due to limitations such as the long time required to adjust the water content of rice grains. Therefore, this work was carried out to shorten the soaking time of glutinous rice (GR) by hot air pretreatment, and to conduct a systematic and in-depth study of the effect of water content on the quality of GRF, including water distribution, water hydration properties, thermal properties, rheological properties, and microstructure. The results showed that the GRF with higher water content had lower water solubility and higher enthalpy of pasting, which were due to the low content of damaged starch and the high degree of crystallization. The particle size of the GRF became smaller as the interaction between water and starch was enhanced and the GR was softened. In addition, the viscosity and elasticity of the GRF were also improved with an increase in water content. This work provides theoretical guidance for the improvement of semidry grinding to a certain extent.

9.
Molecules ; 29(20)2024 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-39459328

RESUMO

To achieve artificial photosynthesis, it is crucial to develop a catalytic system for CO2 reduction using water as the electron source. However, photochemical CO2 reduction by homogeneous molecular catalysts has predominantly been conducted in organic solvents. This study investigates the impact of water content on catalytic activity in photochemical CO2 reduction in N,N-dimethylacetamide (DMA), using [Ru(bpy)3]2+ (bpy: 2,2'-bipyridine) as a photosensitizer, 1-benzyl-1,4-dihydronicotinamide (BNAH) as an electron donor, and two ruthenium diimine carbonyl complexes, [Ru(bpy)2(CO)2]2+ and trans(Cl)-[Ru(Ac-5Bpy-NHMe)(CO)2Cl2] (5Bpy: 5'-amino-2,2'-bipyridine-5-carboxylic acid), as catalysts. Increasing water content significantly decreased CO and formic acid production. The similar rates of decrease for both catalysts suggest that water primarily affects the formation efficiency of free one-electron-reduced [Ru(bpy)3]2+, rather than the intrinsic catalytic activity. The reduction in cage-escape efficiency with higher water content underscores the challenges in replacing organic solvents with water in photochemical CO2 reduction.

10.
Materials (Basel) ; 17(20)2024 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-39459697

RESUMO

The disposal and reutilization of the enormous amounts of slurry-like mud (MS) dredged from navigation channel construction, ecological dredging, and other construction activities have been receiving increasing attention. In this paper, a flocculation-solidification-high-pressure filtration combined method (FSHCM) is used to treat MS, and the consolidation characteristics of The SHCM-treated MS are studied by conducting a series of one-dimensional consolidation compression tests. Various parameters, including the dosage of the curing agent, initial water content, and dry weight of the MS, are systematically analyzed to evaluate their influence on the consolidation behavior. The experimental results demonstrate that higher curing agent and initial water contents enhance the structural yield stress and compressive resistance, while increased dry weight decreases the structural yield stress but increases the compressive strain and void ratio. As the curing age increases, the ability of the FSHCM-treated MS to resist compressive deformation is further enhanced. In addition, the compressibility of the mud cake samples changes significantly at the yield point. This study has practical guiding significance for the optimal design and long-term application of FSHCM-treated MS.

11.
BMC Ophthalmol ; 24(1): 469, 2024 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-39465378

RESUMO

BACKGROUND: To prospectively evaluate binocular visual outcomes after implantation of trifocal intraocular lenses (IOLs) with high-water-content hydrophobic acrylic material in Japanese patients. METHODS: In 59 patients (mean age 65.1 ± 7.9 years), Clareon PanOptix (CNWTT0: Alcon) with a high-water-content hydrophobic acrylic material was implanted bilaterally. Three months postoperatively, binocular uncorrected visual acuity (BUCVA) and distance-corrected visual acuity (BDCVA) at distances of 5 m, 80, 60, and 40 cm, binocular defocus curves, and binocular photopic contrast sensitivity were examined. Subjective symptoms (night vision disturbance, glare, halos, haze, or blurry vision) were also assessed. RESULTS: The mean postoperative BUCVA/BDCVA at 5 m, 80 cm, 60 cm, and 40 cm were - 0.115/-0.163, -0.052/-0.047, -0.054/-0.075, and - 0.043/-0.067 logMAR, respectively. A smooth defocus curve, contrast sensitivity within the normal range, and acceptable subjective symptom rates were obtained. CONCLUSIONS: The trifocal IOL, composed of a high-water-content hydrophobic acrylic material, provides good continuous binocular vision from distance to near. TRIAL REGISTRATION: This investigator-initiated study was registered in the Japan Registry for Clinical Trials (identifier: jRCTs032220042) on April 26, 2022.


Assuntos
Resinas Acrílicas , Sensibilidades de Contraste , Implante de Lente Intraocular , Lentes Intraoculares Multifocais , Visão Binocular , Acuidade Visual , Humanos , Acuidade Visual/fisiologia , Masculino , Feminino , Idoso , Estudos Prospectivos , Pessoa de Meia-Idade , Sensibilidades de Contraste/fisiologia , Visão Binocular/fisiologia , Interações Hidrofóbicas e Hidrofílicas , Facoemulsificação , Pseudofacia/fisiopatologia , Desenho de Prótese
12.
Environ Sci Pollut Res Int ; 31(50): 60668-60681, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39390306

RESUMO

In this study, we investigated the temporal variation of organic and inorganic aerosol with its optical properties in Mumbai (India), an urban coastal region. Mean PM2.5 concentrations during the sampling period were 175 µg/m3 (winter) and 90 µg/m3 (summer). During winter, the average concentrations of organic (OC), elemental (EC), and water-soluble organic carbon (WSOC) were three times higher than in summer. Secondary organic carbon (SOC) contribution in OC was higher in summer (78%) than in winter (53%), and strong solar radiation in summer likely caused this outcome. Aerosols were slightly acidic in both seasons, with an average pH of 5.7 (winter) and 6.0 (summer). A correlation was observed between SOC and the acidity of particles in summer (R2 = 0.6), indicating some amount of acid-catalysed SOC formation. In both seasons, the sulphate oxidation ratio (SOR) was higher than the nitrate oxidation ratio (NOR), which may reflect a preference for SO2 oxidation over NO2 or the difference in partitioning ammonium nitrate into ammonium sulphate under high RH. The dominant mechanism of SOC formation (gas vs aqueous phase oxidation) also showed seasonal variation. In winter, a relatively steep reduced major axis (RMA) slope of O3/CO suggests gas phase oxidation was the dominant mechanism of SOC production. Winter has more BrC fraction than summer, indicating higher absorbing aerosols, though the efficiency of absorbing the light was higher in summer. To assess the radiative forcing of PM2.5 on a local scale, an effective carbon ratio (ECR) was computed. The findings pointed to a local radiative heating impact caused by PM2.5. The spectral slope ratio and MAE at 250 to 300 nm ratio (E2/E3) revealed a higher abundance of high molecular weight species in WSOC during summer than in winter.


Assuntos
Aerossóis , Poluentes Atmosféricos , Monitoramento Ambiental , Material Particulado , Estações do Ano , Aerossóis/análise , Poluentes Atmosféricos/análise , Material Particulado/análise , Índia , Carbono/análise
13.
Sci Total Environ ; 952: 175916, 2024 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-39226962

RESUMO

Riparian trees are particularly vulnerable to drought because they are highly dependent on water availability for their survival. However, the response of riparian tree species to water stress varies depending on regional hydroclimatic conditions, making them unevenly vulnerable to changing drought patterns. Understanding this spatial variability in stress responses requires a comprehensive assessment of water stress across broader spatial and temporal scales. Yet, the precise ecophysiological mechanisms underlying these responses remain poorly linked to remotely sensed indices. To address this gap, the implementation of remote sensing methods coupled with in situ validation is essential to obtain consistent results across diverse spatial and temporal contexts. We conducted a multi-tool analysis combining multispectral and thermal remote sensing indices with in situ ecophysiological measurements at different temporal scales to analyze the responses of white poplar (Populus alba) to seasonal changes in drought along a hydroclimatic gradient. Using this approach, we demonstrate that white poplars along the Rhône River (France) exhibit contrasting responses and behaviors during drought depending on the latitudinal context. White poplars in a Mediterranean climate show rapid stomatal closure to reduce water loss and maintain high minimum water potential levels, although this results in a decrease in remotely sensed greenness. Conversely, white poplars located upstream in a temperate climate show high transpiration and stable greenness but lower minimum water potential and water content. A site in the middle of the gradient has intermediate responses. These results demonstrate that white poplars along a climate gradient can have a range of responses to drought along the iso/anisohydricity continuum. These results are important for future climatic conditions because they show that the same species can have different mechanisms of drought resilience, even in the same river valley. This raises questions regarding how these riparian tree populations will respond to future climatic and hydrological conditions.


Assuntos
Populus , Árvores , Árvores/fisiologia , Animais , Populus/fisiologia , Gafanhotos/fisiologia , Secas , Rios , França , Desidratação , Clima , Monitoramento Ambiental/métodos
14.
J Sci Food Agric ; 2024 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-39221962

RESUMO

BACKGROUND: Water content and chlorophyll content are important indicators for monitoring rice growth status. Simultaneous detection of water content and chlorophyll content is of significance. Different varieties of rice show differences in phenotype, resulting in the difficulties of establishing a universal model. In this study, hyperspectral imaging was used to detect the Soil and Plant Analyzer Development (SPAD) values and water content of fresh rice leaves of three rice varieties (Jiahua 1, Xiushui 121 and Xiushui 134). RESULTS: Both partial least squares regression and convolutional neural networks were used to establish single-task and multi-task models. Transfer component analysis (TCA) was used as transfer learning to learn the common features to achieve an approximate identical distribution between any two varieties. Single-task and multi-task models were also built using the features of the source domain, and these models were applied to the target domain. These results indicated that for models of each rice variety the prediction accuracy of most multi-task models was close to that of single-task models. As for TCA, the results showed that the single-task model achieved good performance for all transfer learning tasks. CONCLUSION: Compared with the original model, good and differentiated results were obtained for the models using features learned by TCA for both the source domain and target domain. The multi-task models could be constructed to predict SPAD values and water content simultaneously and then transferred to another rice variety, which could improve the efficiency of model construction and realize rapid detection of rice growth indicators. © 2024 Society of Chemical Industry.

15.
Proc Biol Sci ; 291(2031): 20240642, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39288804

RESUMO

Nutrient addition, particularly nitrogen, often increases plant aboveground biomass but causes species loss. Asymmetric competition for light is frequently assumed to explain the biomass-driven species loss. However, it remains unclear whether other factors such as water can also play a role. Increased aboveground leaf area following nitrogen addition and warming may increase transpiration and cause water limitation, leading to a decline in diversity. To test this, we conducted field measurements in a grassland community exposed to nitrogen and water addition, and warming. We found that warming and/or nitrogen addition significantly increased aboveground biomass but reduced species richness. Water addition prevented species loss in either nitrogen-enriched or warmed treatments, while it partially mitigated species loss in the treatment exposed to increases in both temperature and nitrogen. These findings thus strongly suggest that water limitation can be an important driver of species loss as biomass increases after nitrogen addition and warming when soil moisture is limiting. This result is further supported by a meta-analysis of published studies across grasslands worldwide. Our study indicates that loss of grassland species richness in the future may be greatest under a scenario of increasing temperature and nitrogen deposition, but decreasing precipitation.


Assuntos
Biodiversidade , Biomassa , Pradaria , Nitrogênio , Água , Nitrogênio/metabolismo , Temperatura , Aquecimento Global , Poaceae/fisiologia
16.
Front Plant Sci ; 15: 1428212, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39309177

RESUMO

Water is a crucial component for plant growth and survival. Accurately estimating and simulating plant water content can help us promptly monitor the physiological status and stress response of vegetation. In this study, we constructed water loss curves for three types of conifers with morphologically different needles, then evaluated the applicability of 12 commonly used water indices, and finally explored leaf water content estimation from hyperspectral data for needles with various morphology. The results showed that the rate of water loss of Olgan larch is approximately 8 times higher than that of Chinese fir pine and 21 times that of Korean pine. The reflectance changes were most significant in the near infrared region (NIR, 780-1300 nm) and the short-wave infrared region (SWIR, 1300-2500 nm). The water sensitive bands for conifer needles were mainly concentrated in the SWIR region. The water indices were suitable for estimating the water content of a single type of conifer needles. The partial least squares regression (PLSR) model is effective for the water content estimation of all three morphologies of conifer needles, demonstrating that the hyperspectral PLSR model is a promising tool for estimating needles water content.

17.
Heliyon ; 10(18): e37530, 2024 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-39309888

RESUMO

With the intensification of global change, forests are subjected to varying degrees of drought or high-temperature stress, which has an indelible impact on the growth of trees. However, knowledge on the response of sap flow to environmental changes in different types of forests is still rare, especially in China's subtropical forest ecosystem. Consequently, studying how different tree species regulate their sap flow in response to shifting environmental conditions is essential for understanding forest transpiration, water use efficiency, and drought stress resilience. Therefore, this study aimed to investigate the sap flow dynamics of seven tree species in five forest plots, i.e., pine forest (PF), two types of mixed conifer-broadleaf forests (MF1+MF2), monsoon evergreen broadleaved forest (MEBF), and montane monsoonal evergreen broad-leaf forest (MOBF) at Dinghushan National Reserve in Southern China, using the heat dissipation probe technique and synchronous environmental factor recordings. Results demonstrated a significant influence of photosynthetic active radiation (PAR) on sap flow across all tree species, with mean PAR values ranging from over 1200 to 425 µmol m-2 s-1, establishing it as the principal driving factor. This observation underscores the heightened responsiveness or sensitivity of tree species to variations in PAR as the forest undergoes development and maturation. The correlation between vapor pressure deficit (VPD) and tree sap flow decreased as succession progressed. Moreover, the influence of soil water content (SWC) on sap flow stability against environmental changes increased. Similar patterns were also found between the two MF, with MF-2 displaying ecological characteristics and environmental conditions more closely aligned with those of the late-successional MEBF. The study reveals the intricate relationship between environmental factors and sap flow regulation in tree species within a subtropical forest ecosystem. Addressing a comparative gap in sap flow correlation among dominant tree species at Dinghushan, it establishes a hydro-physiological foundation for understanding tree species substitution during forest succession. The results provide key insights for forest management and climate-related research. Future studies should delve into the long-term implications of observed sap flow dynamics, exploring their impact on tree species adaptability amid ongoing environmental changes.

18.
Heliyon ; 10(17): e37152, 2024 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-39296113

RESUMO

In arid regions, one of the practical solutions to overcome the water shortage and increasing soil fertility is application of salicylic acid (SA) with biochar. A pot experiment was conducted to consider the combination of SA with biochar on biochemical and physiological parameters of triticale as a factorial experiment using a completely randomized design (RCD) with four replicates. Treatments consisted of irrigation regime (normal irrigation and irrigation according to 50 % field capacity), salicylic acid application [without SA (SA0) and 3 mM SA (SA3)] and fertilizer type including without fertilizer (control), application of 50 kg ha-1 phosphorus (P), and application of wheat biochar (WB), cotton biochar (CB) and sesame biochar (SB) (2 % w/w). Under water stress, CB at SA0 and SA3 could improve the total chlorophyll by 119.4 and 70.6 %, compared to control, respectively. Also, carotenoid content in SA3 treatments increased in the range of 75.8 to 34.6 % compared to SA0. CB at SA3, increased catalase activity by 11.4 % compared to SB. At SA3, the highest RWC was observed in WB and CB by 26.7 and 18.1 % increases compared to SA0, respectively. At SA3, CB could enhance grain yield by 24.8 % under water stress. Under water stress, at SA3, remobilization efficiency from 63.2 % in control was enhanced to 69.2, 74.3 and 68.1 % in WB, CB and SB, respectively. CB and WB had better chemical properties in terms of EC, N, P, K and micronutrients compared to SB. These properties of BC and WB enhanced their ability to increase the nutrient availability, biochemical properties and consequently the grain yield enhancement, especially when applied with SA3.

19.
Sci Total Environ ; 950: 175329, 2024 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-39122025

RESUMO

To investigate the relationship between microphysical and chemical characteristics of size-resolved fog droplets in different regional backgrounds, we conducted observational experiments in urban, mountainous, rainforest, and rural areas of China. Fog water samples across different diameter ranges (4-16 µm, 16-22 µm, and >22 µm) were collected, alongside fog droplet spectra data. Our findings reveal a close relationship between pH value, electrical conductivity (EC), total ion concentration (TIC) of droplets, and droplet sizes, with smaller droplets exhibiting stronger acidity and higher ion concentrations. Significant differences in chemical composition are observed across size ranges and regional backgrounds. Droplet number concentration (N) and liquid water content (LWC) distributions in different regional backgrounds are skewed, with peak diameters of LWC spectra similar to those of N spectra, yet overall spectral distributions varied significantly. Droplet number concentrations are highest in urban area, while large droplets contribute more to overall LWC in mountainous, rainforest, and rural areas. No direct evidence linked LWC or surface area (S) to LWC ratio to water-soluble ion concentrations of size-resolved fog droplets in different regional backgrounds. However, by adjusting the contributions of S and LWC proportions of different-sized droplets to the ion concentration proportions, we find that expanding the LWC proportion to 2.43 times and decreasing the S proportion to 0.2 times for large droplets, while decreasing the LWC ratio to 0.76 times for small droplets, provided a better explanation for the distribution of ion concentrations. This study advances our understanding of the intricate relationship between the microphysical and chemical characteristics of fog, helping to develop more robust and comprehensive models for fog prediction and management.

20.
Sci Rep ; 14(1): 20228, 2024 08 30.
Artigo em Inglês | MEDLINE | ID: mdl-39215054

RESUMO

A two-year field trial was set up to investigate the effects of applying 3 tons ha-1 of wheat (3WB) and cotton biochar (3CB) alone or in combination with chemical nitrogen (N) and phosphorus (P) fertilizers on biochemical properties, yield and nutrient content of safflower under normal irrigation and water stress (irrigation cut-off at flowering stage) conditions. The total water applied in the chemical treatments [150 kg ha-1 N + 50 kg ha-1 P (100% of the recommended dose) and 112.5N + 37.5P (75% of the recommended dose)] under water stress, was significantly higher than other treatments. Application of 112.5N + 37.5P + 3CB increased RWC from 57.5 to 59.4% and the total chlorophyll content from 80.7 to 128.1%, compared to the control. The carotenoid content, catalase and peroxidase in 112.5N + 37.5P + 3CB were lower than chemical fertilizers. Under water stress, the seed yield of 112.5N + 37.5P + 3CB was 10.2-12.6% higher than 112.5N + 37.5P + 3WB. The higher chlorophyll content, RWC, remobilization efficiency and nutrient content in 112.5N + 37.5P + 3CB compared to other treatments was associated with seed yield enhancement. The findings indicate that the combination of CB with 75% recommended dosage of N and P, may be the optimal approach for enhancing safflower production under water stress conditions.


Assuntos
Carthamus tinctorius , Carvão Vegetal , Clorofila , Fertilizantes , Nutrientes , Carthamus tinctorius/metabolismo , Carthamus tinctorius/química , Carvão Vegetal/química , Carvão Vegetal/farmacologia , Clorofila/metabolismo , Fertilizantes/análise , Nutrientes/análise , Nutrientes/metabolismo , Nitrogênio/metabolismo , Nitrogênio/análise , Fósforo/análise , Fósforo/metabolismo , Água/química , Desidratação , Carotenoides/metabolismo
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