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1.
Ying Yong Sheng Tai Xue Bao ; 35(5): 1321-1330, 2024 May.
Article de Chinois | MEDLINE | ID: mdl-38886431

RÉSUMÉ

Rapid acquisition of the data of soil moisture content (SMC) and soil organic matter (SOM) content is crucial for the improvement and utilization of saline alkali farmland soil. Based on field measurements of hyperspectral reflectance and soil properties of farmland soil in the Hetao Plain, we used a competitive adaptive reweighted sampling algorithm (CARS) to screen sensitive bands after transforming the original spectral reflectance (Ref) into a standard normal variable (SNV). Strategies Ⅰ, Ⅱ, and Ⅲ were used to model the input variables of Ref, Ref SNV, Ref-SNV+ soil covariate (SC), and digital elevation model (DEM). We constructed SMC and SOM estimation models based on random forest (RF) and light gradient boosting machine (LightGBM), and then verified and compared the accuracy of the models. The results showed that after CARS screening, the sensitive bands of SMC and SOM were compressed to below 3.3% of the entire band, which effectively optimized band selection and reduced redundant spectral information. Compared with the LightGBM model, the RF model had higher accuracy in SMC and SOM estimation, and the input variable strategy Ⅲ was better than Ⅱ and Ⅰ. The introduction of auxiliary variables effectively improved the estimation ability of the model. Based on comprehensive analysis, the coefficient of determination (Rp2), root mean square error (RMSE), and relative analysis error (RPD) of the SMC estimation model validation based on strategy Ⅲ-RF were 0.63, 3.16, and 2.01, respectively. The SOM estimation models based on strategy Ⅲ-RF had Rp2, RMSE, and RPD of 0.93, 1.15, and 3.52, respectively. The strategy Ⅲ-RF model was an effective method for estimating SMC and SOM. Our results could provide a new method for the rapid estimation of soil moisture and organic matter content in saline alkali farmland.


Sujet(s)
Algorithmes , Composés chimiques organiques , Sol , Eau , Sol/composition chimique , Composés chimiques organiques/analyse , Eau/analyse , Produits agricoles/croissance et développement , Produits agricoles/composition chimique , Alcalis/analyse , Alcalis/composition chimique , Chine , Écosystème
2.
Ying Yong Sheng Tai Xue Bao ; 35(5): 1283-1292, 2024 May.
Article de Chinois | MEDLINE | ID: mdl-38886427

RÉSUMÉ

To investigate the effects of different irrigation and nitrogen application modes on nitrogen gaseous loss in winter wheat farmland, we conducted a field experiment at Changqing Irrigation Experiment Station in Shandong Province, with two irrigation levels (80%-90% θf(I1) and 70%-80% θf(I2)) and three nitrogen application levels (conventional nitrogen application of 240 kg·hm-2(N1), nitrogen reduction of 12.5% (N2), and nitrogen reduction of 25% (N3)). The results showed that ammonia volatilization and nitrous oxide emission rate peak appeared within 2-4 days after fertilization or irrigation. The ammonia volatilization rate during the chasing fertilizer period was significantly higher than that during the basal fertilizer period. Compared with other treatments, the ave-rage ammonia volatilization rate of I2N2 treatment during the chasing fertilizer period was reduced by 10.1%-51.6%, and the average nitrous oxide emission rate over the whole growth period was reduced by 15.4%-52.2%. The ammonia volatilization rate was significantly positively associated with surface soil pH value and ammonium nitrogen content, while the nitrous oxide emission rate was significantly positively associated with nitrate content in topsoil. The accumulation amount of soil ammonia volatilization and nitrous oxide emission ranged from 0.83-1.42 and 0.11-0.33 kg·hm-2, respectively. Moderate reduction of irrigation water and nitrogen input could effectively reduce cumulative amounts of ammonia volatilization and nitrous oxide emission from winter wheat farmland. The cumulative amounts of ammonia volatilization and nitrous oxide emission under I1N3 and I2N2 treatments were signi-ficantly lower than those under other treatments. The highest winter wheat yield (5615.6 kg·hm-2) appeared in I2N2 treatment. The irrigation water utilization efficiency of I2 was significantly higher than that of I1, with the maximum increase rate of 45.2%. Compared with N1 and N3 treatments, the maximum increase rate of nitrogen fertilizer productivity and agricultural utilization efficiency in N2 reached 15.2% and 31.8%, respectively. In conclusion, the treatment with 70%-80% θf irrigation level and 210 kg·hm-2 nitrogen input could effectively improve the utilization efficiency of irrigation water and nitrogen fertilization and reduce gaseous loss from winter wheat farmland.


Sujet(s)
Ammoniac , Engrais , Azote , Protoxyde d'azote , Triticum , Eau , Triticum/croissance et développement , Triticum/métabolisme , Protoxyde d'azote/analyse , Protoxyde d'azote/métabolisme , Azote/analyse , Azote/métabolisme , Ammoniac/analyse , Ammoniac/métabolisme , Chine , Eau/analyse , Eau/métabolisme , Irrigation agricole/méthodes , Saisons , Biomasse , Sol/composition chimique
3.
J Acupunct Meridian Stud ; 17(3): 86-93, 2024 Jun 30.
Article de Anglais | MEDLINE | ID: mdl-38898645

RÉSUMÉ

Importance: Understanding acupuncture point microenvironments is vital for optimizing treatment efficacy. Evaluating changes in water content at these points can provide further insights into the effects of acupuncture on tissues. Objective: This study aimed to measure tissue dielectric constant (TDC) and assess changes in water content, specifically at stomach 36 (ST36, Zusanli) and spleen 6 (SP6, Sanyinjiao) acupuncture points. Methods: In a controlled, blinded, randomized trial, 113 healthy volunteers were divided into six groups based on TDC sensor diameters (XS, M, and L): three control groups and three acupuncture groups. They were assessed at three time points: T1, baseline; T2, 20 min post-needle withdrawal; and T3, 40 min post-needle withdrawal. Electrical impedance (EI) was also analyzed. Significance level was set at p < 0.001. Results: TDC at ST36 and SP6 significantly decreased with the XS probe at T2 and T3 compared with that at T1 (F8, 452: 54.61). TDC did not significantly vary between T2 and T3 with M and L probes. EI data indicated that the current passage increased in the SP (F2, 226: 39.32) and ST (F2, 226: 37.32) groups during T2 and T3 compared with that during T1 within their respective groups and controls. Conclusions: and Relevance: This study demonstrated the efficacy of TDC measurements in detecting water content fluctuations at acupuncture points and their responses to needles. TDC measurements, which were validated against EI, provide valuable insights into acupuncture point microenvironments and thus help optimize treatments.


Sujet(s)
Points d'acupuncture , Impédance électrique , Eau , Humains , Mâle , Femelle , Adulte , Eau/analyse , Jeune adulte , Thérapie par acupuncture/méthodes , Volontaires sains , Adulte d'âge moyen
4.
Molecules ; 29(11)2024 Jun 04.
Article de Anglais | MEDLINE | ID: mdl-38893519

RÉSUMÉ

Nitrite is one of the most common nitrogenous compounds, which is not only an important indicator of aquaculture water but also widely used as a food additive. Its potential toxicity poses a huge threat to aquatic products and human health. Therefore, it is important to develop a convenient and rapid sensor for the high-efficient onsite detection of nitrite. In this work, a novel electrochemical sensor was developed for the qualitative and quantitative analysis of nitrite. The developed nitrite electrochemical detection system is easily applied in onsite detection. The electrochemical working electrode was constructed based on the combination of Ag-CeO2 and conductive carbon paste (CPE) with excellent electrocatalysis activity and rapid electron transfer ability. By the application of the developed system and under the optimal conditions, the linear range was from 40.0 µM to 500.0 µM, and the detection limit was reduced to 4.3 µM. The recovery was between 92.1% and 108.1%, and the relative standard deviations (RSDs) were 0.49%~9.31%. The sensor exhibited superior reproducibility, high stability sensitivity, and anti-interference ability, confirming its effectiveness for nitrite analysis. Finally, the developed electrochemical sensor was successfully applied to detect nitrite in beverages and aquaculture water samples, indicating that this approach has great potential in onsite food testing and environmental monitoring.


Sujet(s)
Aquaculture , Boissons , Cérium , Techniques électrochimiques , Nitrites , Nitrites/analyse , Techniques électrochimiques/méthodes , Cérium/composition chimique , Boissons/analyse , Argent/composition chimique , Limite de détection , Polluants chimiques de l'eau/analyse , Électrodes , Reproductibilité des résultats , Eau/composition chimique , Eau/analyse
5.
Ying Yong Sheng Tai Xue Bao ; 35(4): 886-896, 2024 Apr 18.
Article de Chinois | MEDLINE | ID: mdl-38884223

RÉSUMÉ

Elucidating the seasonal patterns of water sources for dominant species in the sub-tropical humid mountainous forest, analyzing the eco-hydrological complementarity and competition mechanisms among coexisting species, investigating the responses of plant water utilization to precipitation, could provide a theoretical basis for vegetation restoration and management. Based on the stable hydrogen and oxygen isotope technique, we analyzed the δ2H and δ18O characteristics of precipitation, xylem water from Pinus massoniana and Quercus variabilis, and soil water from 0-100 cm depth in Mount Lushan, China. The MixSIAR model, Levins index, and PS index were used to calculate the relative contribution rate of each water source, the hydrological niche breadth, and niche overlap of P. massoniana and Q. variabilis. The results showed that, in the wet season (March to July), P. massoniana primarily utilized soil water from the 0-20 cm and 20-40 cm depths, while Q. variabilis primarily utilized that from the 20-40 cm and 40-60 cm depths. During the dry season (August to September), P. massoniana and Q. variabilis utilized 40-60 cm and 60-80 cm of soil water, respectively, resulting in an increase in the depth of water absorption. In the early growing season (March to April) and the late growing season (September), there was a high hydrological niche overlap between P. massoniana and Q. variabilis, resulting in intensitive water competition. In the middle of the growing season (May to August), the water source was adequately allocated, and the hydrolo-gical niche was segregated to meet the high transpiration demand. Q. variabilis primarily utilized soil water from a depth of 60-80 cm and 60-80 cm before a precipitation event, and from a depth of 0-20 cm and 20-40 cm after the event. In contrast, P. massoniana primarily utilized soil water from a depth of 0-20 cm and 20-40 cm both before and after a precipitation event. In conclusion, water utilization patterns of P. massoniana and Q. variabilis exhibited a seasonal trend, with shallow water uptake during the rainy season and deep water uptake during the dry season. These species are capable of efficiently allocating water resources during the peak growth season, and their root systems actively respond to change in soil moisture level. They have strong adaptability to extreme precipitation events and exhibit remarkable water conservation capabilities.


Sujet(s)
Forêts , Pinus , Quercus , Pluie , Saisons , Eau , Chine , Eau/analyse , Eau/métabolisme , Quercus/croissance et développement , Pinus/croissance et développement , Écosystème , Sol/composition chimique
6.
Ying Yong Sheng Tai Xue Bao ; 35(4): 909-916, 2024 Apr 18.
Article de Chinois | MEDLINE | ID: mdl-38884225

RÉSUMÉ

The stoichiometric characteristics of leaves can reflect environmental adaptation of plants, and thus the study of the relationship between them is helpful for exploring plant adaptation strategies. In this study, taking the national second-level key protection species, Ammopiptanthus mongolicus, as the research object, we set up 26 plots to collect samples, and measured the content of carbon (C), nitrogen (N), phosphorus (P) and water use efficiency (WUE) of leaves. We analyzed the relationship between leaf stoichiometric characteristics and WUE, and quantified the contributions of soil, climate, and water use efficiency to the variations of leaf stoichiometry. The results showed that C, N, and P contents in the leaves were (583.99±27.93), (24.31±2.09), and (1.83±0.06) mg·g-1, respectively. The coefficients of variation were 4.8%, 8.6%, and 3.2%, respectively, all belonging to weak variability, indicating that foliar contents of C, N and P tended to a certain stable value. The average value of N:P was 13.3, indicating that the growth of A. mongolicus was mainly limited by N. WUE was not correlated with leaf C content, but was significantly positively correlated with leaf N and P contents and N:P, and significantly negatively correlated with C:N and C:P, indicating that there was a linear synergistic trend between WUE and leaf nutrient content. The main factors influencing leaf C content and C:P were climatic factors, the leaf N content and N:P were mainly affected by soil factors, and the water use efficiency mainly affected leaf P content and C:N, indicating that the driving factors of different stoichiometric characteristics were different. The results could help eva-luate the habitat adaptation of desert plants, which would provide a theoretical basis for the conservation and management of A. mongolicus.


Sujet(s)
Carbone , Azote , Phosphore , Feuilles de plante , Feuilles de plante/composition chimique , Feuilles de plante/métabolisme , Feuilles de plante/croissance et développement , Chine , Azote/analyse , Azote/métabolisme , Phosphore/analyse , Phosphore/métabolisme , Carbone/analyse , Carbone/métabolisme , Écosystème , Eau/analyse , Eau/métabolisme , Eau/composition chimique , Adaptation physiologique , Sol/composition chimique
7.
Ying Yong Sheng Tai Xue Bao ; 35(4): 897-908, 2024 Apr 18.
Article de Chinois | MEDLINE | ID: mdl-38884224

RÉSUMÉ

Understanding water absorption mechanisms of sand-fixing plants is important for the rational establishment of plant community structures, thereby providing a scientific basis for desertification control and the efficient utilization of water resources in sandy areas. Based on the hydrogen and oxygen isotopic compositions of precipi-tation, soil water, xylem water, and groundwater, coupled with soil water-heat dynamics, annual water consumption characteristics of vegetation, using the multi-source linear mixing model (IsoSource), we analyzed the differences in water sources between Salix psammophila and Artemisia ordosica, during winter and the growing season. We further examined the effects of groundwater depth (2 m and 10 m), soil freezing-thawing, and drought on their water utilization to elucidate water absorption mechanisms of those species. The results showed that: 1) During soil freezing-thawing period (January to March), S. psammophila mainly utilized soil water in 60-120 cm depths below the frozen layer (69.1%). In the green-up season (April and May), soil water from the 0-60 cm layers could satisfy the water demand of S. psammophila (30.9%-87.6%). During the dry period of the growing season (June), it predominantly utilized soil water at the depth of 120-160 cm (27.4%-40.8%). Over the rainy season (July and September), soil water in 0-60 cm depths provided 59.8%-67.9% of the total water required. A. ordosica, with shallow roots, could not utilize soil water after complete freezing of root zone but could overwinter by storing water in rhizomes during autumn. During the growing season, it primarily relied on 0-40 cm soil layer (23.4%-86.8%). During the dry period, it mainly utilized soil water from 40-80 cm and 80-160 cm soil layers, with utilization rates of 14.6%-74.4% and 21.8%-78.2%, respectively. 2) With decreasing groundwater depth, vegetation shifted its water absorption depth upward, with water source of S. psammophila transitioning from 120-160 cm to 60-160 cm layers, while A. ordosica shifted water absorption depth from 80-160 cm to 0-40 cm. S. psammophila's utilization of soil water is influenced by transpiration, adopting an "on-demand" approach to achieve a balance between water supply and energy conservation, whereas A. ordosica tends to utilize shallow soil water, exhibiting a higher depen-dence on water sources from a single soil layer.


Sujet(s)
Artemisia , Salix , Sable , Sol , Eau , Eau/analyse , Eau/métabolisme , Artemisia/croissance et développement , Artemisia/métabolisme , Chine , Sol/composition chimique , Salix/croissance et développement , Salix/métabolisme , Climat désertique , Nappe phréatique/composition chimique , Nappe phréatique/analyse , Écosystème
8.
Ying Yong Sheng Tai Xue Bao ; 35(4): 1007-1015, 2024 Apr 18.
Article de Chinois | MEDLINE | ID: mdl-38884235

RÉSUMÉ

Soil matrix infiltration is an important pathway for plantations to obtain water, which affects ecological benefits and water conservation function of plantations. The changes of soil matrix infiltration and its influencing factors in different growth stages of Chinese fir plantations remain unclear. We measured soil matrix infiltration process using a tension infiltrometer in Chinese fir plantations (5, 8, 11, and 15 years old) of Beijiang River Forest Farm in Rongshui, Guangxi, and analyzed soil basic physicochemical properties to identify the dominant factors influencing soil matrix infiltration. The results showed that initial infiltration rate, stable infiltration rate, and cumulative infiltration increased with stand ages. The ranges of different stand ages were 141-180 mm·h-1, 109-150 mm·h-1, and 188-251 mm, respectively. The initial infiltration rate, stable infiltration rate, and cumulative infiltration were significantly positively correlated with soil capillary porosity, soil organic matter, soil water stable macroaggregate, sand content, and clay content, while negatively correlated with soil bulk density and silt content. Early thinning had a positive effect on soil matrix infiltration, but thinning measures after 11 years did not enhance soil matrix infiltration further. Philip model was optimal for describing soil matrix infiltration process in this region. In conclusion, soil matrix infiltration capacity of Chinese fir plantations gradually increased from young to middle-aged stands, but matrix infiltration capacity tended to stabilize after 11 years old. Silt content and water stable macroaggregate were the dominant factors influencing matrix infiltration.


Sujet(s)
Sol , Sol/composition chimique , Chine , Cunninghamia/croissance et développement , Eau/analyse , Écosystème , Facteurs temps , Abies/croissance et développement
9.
Ying Yong Sheng Tai Xue Bao ; 35(4): 997-1006, 2024 Apr 18.
Article de Chinois | MEDLINE | ID: mdl-38884234

RÉSUMÉ

Water use efficiency (WUE) is a key indicator for predicting the impacts of climate change on ecosystem carbon and water cycles. Most studies have explored the changes in the response environment of WUE at a particular scale. Few studies have examined how WUE responds to environments at multiple scales, thus limiting our in-depth understanding of the cross-scale carbon and water cycles. In this study, we measured photosynthesis and transpiration in situ periodically and continuously from June to October 2022 in a community dominated by Artemisia ordosica in Mu Us Sandy Land, and analyzed the seasonal variations in WUE at leaf, canopy, and ecosystem scales. The results showed there were significant seasonal variations in leaf water use efficiency (WUEL), canopy water use efficiency (WUET), and ecosystem water use efficiency (WUEE). WUEL was large in June and small in both August and September, ranging from 0.73-2.98 µmol·mmol-1. Both WUET and WUEE were lowest in June and highest in July and August, ranging from 0.10-7.00 and 0.06-6.25 µmol·mmol-1. WUEL was significantly negatively correlated with stomatal conductance. WUET was significantly positively correlated with canopy conduc-tance and soil water content, and negatively correlated with vapor pressure deficit (VPD). There was a significant positive correlation between WUEE and soil water content (SWC10) in 10 cm soil depth. The structural equation model showed that SWC10 and air temperature affected net photosynthetic rate and transpiration rate by modifying stomatal conductance, and thus affecting WUEL. VPD and SWC10 affected WUET by altering transpiration. SWC10, air temperature, and VPD affected WUEE by regulating ecosystem gross primary productivity. The modelling of carbon and water cycles should thoroughly consider the path and intensity of the effect of environmental factors on WUE at multiple scales.


Sujet(s)
Artemisia , Écosystème , Photosynthèse , Feuilles de plante , Transpiration des plantes , Eau , Artemisia/métabolisme , Artemisia/croissance et développement , Artemisia/physiologie , Eau/métabolisme , Eau/analyse , Chine , Feuilles de plante/métabolisme , Feuilles de plante/composition chimique , Climat désertique , Changement climatique , Saisons
10.
Ying Yong Sheng Tai Xue Bao ; 35(4): 1064-1072, 2024 Apr 18.
Article de Chinois | MEDLINE | ID: mdl-38884241

RÉSUMÉ

Transpiration is a significant part of water cycle in forest ecosystems, influenced by meteorological factors and potentially constrained by soil moisture. We used Granier-type thermal dissipation probes to monitor xylem sap flow dynamics of three tree species (Quercus liaotungensis, Platycladus orientalis, and Robinia pseudoacacia) in a semi-arid loess hilly region, and to continuously monitor the key meteorological factors and soil water content (SWC). We established the SWC thresholds delineating soil moisture-limited and -unlimited sap flow responses to transpiration drivers. The results showed that mean sap flux density (Js) of Q. liaotungensis and R. pseudoacacia was significantly higher during period with higher soil moisture compared to lower soil moisture, while the difference in Js for P. orientalis between the two periods was not significant. We used an exponential saturation function to fit the relationship between the Js of each tree species and the integrated transpiration variable (VT) which reflected solar radiation and vapor pressure deficit. The difference in the fitting curve parameters indicated that there were distinct response patterns between Js and VT under different soil moisture conditions. There was a threshold in soil moisture limitation on sap flow for each species, which was identified as 0.129 m3·m-3 for Q. liaotungensis, 0.116 m3·m-3 for P. orientalis, and 0.108 m3·m-3 for R. pseudoacacia. Below the thresholds, Js was limited by soil moisture. Above these points, the normalized sensitivity index (NSI) for Q. liaotungensis and P. orientalis reached saturation, while that of R. pseudoacacia did not reach saturation but exhibited a significant reduction in moisture limitation. Among the three species, P. orientalis was the most capable of overcoming soil moisture constraints.


Sujet(s)
Transpiration des plantes , Sol , Arbres , Eau , Sol/composition chimique , Eau/métabolisme , Eau/analyse , Arbres/croissance et développement , Arbres/physiologie , Arbres/métabolisme , Chine , Quercus/physiologie , Quercus/croissance et développement , Quercus/métabolisme , Écosystème , Robinia/physiologie , Robinia/croissance et développement , Robinia/métabolisme , Forêts , Xylème/physiologie , Xylème/métabolisme , Exsudats végétaux/métabolisme
11.
Glob Chang Biol ; 30(5): e17315, 2024 May.
Article de Anglais | MEDLINE | ID: mdl-38721865

RÉSUMÉ

Grasslands provide important ecosystem services to society, including biodiversity, water security, erosion control, and forage production. Grasslands are also vulnerable to droughts, rendering their future vitality under climate change uncertain. Yet, the grassland response to drought is not well understood, especially for heterogeneous Central European grasslands. We here fill this gap by quantifying the spatiotemporal sensitivity of grasslands to drought using a novel remote sensing dataset from Landsat/Sentinel-2 paired with climate re-analysis data. Specifically, we quantified annual grassland vitality at fine spatial scale and national extent (Germany) from 1985 to 2021. We analyzed grassland sensitivity to drought by testing for statistically robust links between grassland vitality and common drought indices. We furthermore explored the spatiotemporal variability of drought sensitivity for 12 grassland habitat types given their different biotic and abiotic features. Grassland vitality maps revealed a large-scale reduction of grassland vitality during past droughts. The unprecedented drought of 2018-2019 stood out as the largest multi-year vitality decline since the mid-1980s. Grassland vitality was consistently coupled to drought (R2 = .09-.22) with Vapor Pressure Deficit explaining vitality best. This suggests that high atmospheric water demand, as observed during recent compounding drought and heatwave events, has major impacts on grassland vitality in Central Europe. We found a significant increase in drought sensitivity over time with highest sensitivities detected in periods of extremely high atmospheric water demand, suggesting that drought impacts on grasslands are becoming more severe with ongoing climate change. The spatial variability of grassland drought sensitivity was linked to different habitat types, with declining sensitivity from dry and mesic to wet habitats. Our study provides the first large-scale, long-term, and spatially explicit evidence of increasing drought sensitivities of Central European grasslands. With rising compound droughts and heatwaves under climate change, large-scale grassland vitality loss, as in 2018-2019, will thus become more likely in the future.


Sujet(s)
Changement climatique , Sécheresses , Prairie , Technologie de télédétection , Allemagne , Eau/analyse , Atmosphère
12.
Spectrochim Acta A Mol Biomol Spectrosc ; 316: 124287, 2024 Aug 05.
Article de Anglais | MEDLINE | ID: mdl-38701573

RÉSUMÉ

The application of Near Infrared (NIR) spectroscopy for analyzing wet feed directly on farms is increasingly recognized for its role in supporting harvest-time decisions and refining the precision of animal feeding practices. This study aims to evaluate the accuracy of NIR spectroscopy calibrations for both undried, unprocessed samples and dried, ground samples. Additionally, it investigates the influence of the bases of reference data (wet vs. dry basis) on the predictive capabilities of the NIR analysis. The study utilized 492 Corn Whole Plant (CWP) and 405 High Moisture Corn (HMC) samples, sourced from various farms across Italy. Spectral data were acquired from both undried, unground and dried, ground samples using laboratory bench NIR instruments, covering a spectral range of 1100 to 2498 nm. The reference chemical composition of these samples was analyzed and presented in two formats: on a wet matter basis and on a dry matter basis. The study revealed that calibrations based on undried samples generally exhibited lower predictive accuracy for most traits, with the exception of Dry Matter (DM). Notably, the decline in predictive performance was more pronounced in highly moist products like CWP, where the average error increased by 60-70%. Conversely, this reduction in accuracy was relatively contained (10-15%) in drier samples such as HMC. The Standard Error of Cross-Validation (SECV) values for DMres, Ash, CP, and EE were notably low, at 0.39, 0.30, 0.29, 0.21% for CWP and 0.49, 0.14, 0.25, 0.14% for HMC, respectively. These results align with previous studies, indicating the reliability of NIR spectroscopy in diverse moisture contexts. The study attributes this variance to the interference caused by water in 'as is' samples, where the spectral features predominantly reflect water content, thereby obscuring the spectral signatures of other nutrients. In terms of calibration development strategies, the study concludes that there is no significant difference in predictive performance between undried calibrations based on either 'dry matter' or 'as is' basis. This finding emphasizes the potential of NIR spectroscopy in diverse moisture contexts, although with varying degrees of accuracy contingent upon the moisture content of the analyzed samples. Overall, this research provides valuable insights into the calibration strategies of NIR spectroscopy and its practical applications in agricultural settings, particularly for on-farm forage analysis.


Sujet(s)
Aliment pour animaux , Spectroscopie proche infrarouge , Zea mays , Spectroscopie proche infrarouge/méthodes , Calibrage , Zea mays/composition chimique , Aliment pour animaux/analyse , Eau/analyse , Eau/composition chimique , Dessiccation
13.
Anim Sci J ; 95(1): e13952, 2024.
Article de Anglais | MEDLINE | ID: mdl-38689465

RÉSUMÉ

Defatted Lagenaria siceraria seed flour (DLSSF) was obtained from defatted seed cake, dried, and ground through a sieve of 500 µm and characterized. A 2 × 4 factorial design (two flour hydration rates and four fat substitution rates) was used to produce a low-fat beef patty by replacing fat with DLSSF. Beef kidney fat was used to formulate the control sample. Chemical, physical, technological, sensory, and nutritional characteristics of low-fat beef patties manufactured were evaluated. DLSSF contains mainly protein. As fat replacers, DLSSF induces a significant increase in the pH of the raw and cooked patty, the moisture and protein contents, the cooking yield, the cohesion, chewiness, springiness, and lightness of the cooked beef patty with fat substitution rate. There is a decrease in fat content, total calories, water retention capacity, hardness, and redness of the cooked patty with a fat substitution rate. From the sensory analysis, the substitution of fat improves the acceptability of samples. Based on the overall parameters analyzed, DLSSF containing 60% water can be used to produce low-fat beef patty by replacing fat at 100%. From these results, hydrated DLSSF could be an effective method to solve the problems of noncommunicable diseases related to animal fat consumption.


Sujet(s)
Phénomènes chimiques , Cuisine (activité) , Farine , Graines , Graines/composition chimique , Animaux , Bovins , Cuisine (activité)/méthodes , Farine/analyse , Substituts de matières grasses/analyse , Cucurbitaceae/composition chimique , Produits carnés/analyse , Humains , Eau/analyse , Qualité alimentaire , Concentration en ions d'hydrogène , Goût , Valeur nutritive
14.
J Food Sci ; 89(6): 3230-3247, 2024 Jun.
Article de Anglais | MEDLINE | ID: mdl-38767858

RÉSUMÉ

The effects of the storage process on the quality characteristics of a hemp-enriched "tsoureki" (a rich-dough baked Greek product, rich-dough baked product [RDBP]) were investigated. The wheat flour was substituted with defatted hemp flour at selected ratios (0%-50% hemp:wheat flour). The baked products were stored at 25°C and at specific time intervals (0, 1, 4, 7, 10, and 14 days), and their properties were determined, including moisture content, water activity, structure, texture, color, total phenolic content (TPC), and antioxidant activity. Moreover, analyses of phenolic compounds were performed using quadrupole time of flight liquid chromatography-mass spectroscopy, identifying 14 compounds. Both the first-order kinetic model and modified Avrami equation, including the hemp-to-wheat ratio effect in the rate constant, well described the changes in the quality characteristics. The results showed that storage time and hemp incorporation significantly affected the quality of the product. Water activity decreased from 0.901 to 0.859, whereas moisture content decreased from 30.52%-32.33% (0 days) to 26.97%-27.02% w.b. (14 days) with storage time for all hemp additions. Hardness was greatly affected by hemp flour addition and approached 14.72 and 17.85 N after 14 days of storage for 30% and 50% substitutions, respectively. Springiness and cohesiveness decreased with hemp addition and storage time. The color difference of the hemp-enriched products compared to the control sample increased during storage. TPC increased due to the addition of hemp flour, whereas 14 compounds were identified. Based on property correlation, the hemp-enriched RDBP-tsoureki held its high-quality characteristics for 7 days of storage and contained a significant amount of bioactive compounds. PRACTICAL APPLICATION: Industrially produced, defatted hemp is a promising byproduct that can be used to nutritionally enhance baked goods. Modeling results can be used for the prediction of the properties that define product storage ability and also that the hemp-enriched, rich dough-baked Greek "tsoureki" could be produced while maintaining total phenolic content and antioxidant activity during 7 days of storage. These findings are expected to be used in the future in baked goods industry applications to produce goods with an improved nutritional profile.


Sujet(s)
Antioxydants , Cannabis , Farine , Stockage des aliments , Phénols , Cannabis/composition chimique , Stockage des aliments/méthodes , Farine/analyse , Antioxydants/analyse , Phénols/analyse , Triticum/composition chimique , Grèce , Cuisine (activité)/méthodes , Eau/analyse , Couleur
15.
Food Chem ; 453: 139694, 2024 Sep 30.
Article de Anglais | MEDLINE | ID: mdl-38776793

RÉSUMÉ

Previous studies have indicated that hydrogen-rich water (HW) treatment can delay fruit ripening and senescence. However, little is known about the HW-delaying pulp breakdown. In this study, eight physiological characteristics revealed that HW treatment delayed both pericarp browning and pulp breakdown of litchi fruit. To gain a comprehensive understanding of the changes in litchi pulp, a combination of multiple metabolomics and gene expression analyses was conducted, assessing 67 primary metabolites, 103 volatiles, 31 amino acids, and 13 crucial metabolite-related genes. Results showed that HW treatment promoted starch degradation, decelerated cell wall degradation and glycolysis, and maintained the flavor and quality of litchi fruit. Furthermore, HW treatment stimulated the production of volatile alcohols, aldehydes, ketones, olefins, and amino acids, which might play a vital role in HW-delaying pulp breakdown. This study sheds light on the mechanism by which HW delayed pulp breakdown by investigating small molecule metabolites and metabolic pathways.


Sujet(s)
Stockage des aliments , Fruit , Hydrogène , Litchi , Eau , Fruit/composition chimique , Fruit/métabolisme , Fruit/croissance et développement , Litchi/composition chimique , Litchi/métabolisme , Litchi/croissance et développement , Hydrogène/métabolisme , Hydrogène/analyse , Eau/métabolisme , Eau/analyse , Composés organiques volatils/métabolisme , Composés organiques volatils/composition chimique
16.
Food Chem ; 453: 139558, 2024 Sep 30.
Article de Anglais | MEDLINE | ID: mdl-38781892

RÉSUMÉ

The effect of moisture content changes during drying processing on the appearance of sea buckthorn was studied. Using computer vision methods and various image processing methods to collect and analyze images during the drying process of sea buckthorn fruit. Sea buckthorn is dried in a drying oven at a temperature of 65 °C and Level 1 wind speed conditions. The images of the entire drying process of sea buckthorn fruit were collected at 30-min intervals. Deep mining and transformation of image information through various image processing methods. By calibrating and modeling the color components, real-time online detection of the moisture content of sea buckthorn fruit can be achieved. After modeling, this article attempted to use LSTM (Long Short Term Memory) to predict the appearance of sea buckthorn fruit with supercritical moisture content. Different agricultural products adapt to different color spaces, but after standard modeling with a certain amount of data, applying color components to detect moisture content is a very good method.


Sujet(s)
Fruit , Hippophae , Traitement d'image par ordinateur , Eau , Hippophae/composition chimique , Fruit/composition chimique , Eau/analyse , Eau/composition chimique , Traitement d'image par ordinateur/méthodes , Couleur , Dessiccation/méthodes
17.
Food Chem ; 454: 139629, 2024 Oct 01.
Article de Anglais | MEDLINE | ID: mdl-38805920

RÉSUMÉ

In this study, we assessed the impact of varied water deficit irrigation frequencies (T1: 2.5 L/4 days; T2: 5 L/8 days; CK: 5 L/4 days) on Zitian Seedless grapes from veraison to post-ripening. Notably, total soluble solids increased during on-tree storage compared to at maturity, while total anthocyanin content decreased, particularly in CK (60.16%), T1 (62.35%), and less in T2 (50.54%). Glucose and fructose levels increased significantly in T1 and T2, more so in T2, but slightly declined in CK. Tartaric acid content increased by 41.42% in T2. Moreover, compared to regular irrigation, water deficit treatments enhanced phenolic metabolites and volatile compounds, including chlorogenic acid, various flavonoids, viniferin, hexanal, 2-nonenal, 2-hexen-1-ol, (E)-, 3-hydroxy-dodecanoic acid, and 1-hexanol, etc. Overall, the T2 treatment outperformed T1 and CK in maintaining grape quality. This study reveals that combining on-tree storage with water deficit irrigation not only improves grape quality but also water efficiency.


Sujet(s)
Irrigation agricole , Fruit , Vitis , Eau , Vitis/composition chimique , Vitis/croissance et développement , Vitis/métabolisme , Fruit/composition chimique , Fruit/métabolisme , Fruit/croissance et développement , Eau/métabolisme , Eau/analyse , Stockage des aliments , Anthocyanes/analyse , Anthocyanes/métabolisme , Phénols/métabolisme , Phénols/analyse , Arbres/croissance et développement , Arbres/métabolisme , Arbres/composition chimique , Flavonoïdes/analyse , Flavonoïdes/métabolisme
18.
Poult Sci ; 103(7): 103830, 2024 Jul.
Article de Anglais | MEDLINE | ID: mdl-38763060

RÉSUMÉ

Relationships between texture measurements and meat water properties were investigated in raw intact broiler breast fillets with the wooden breast (WB) condition. Texture measurements included subjective WB scores and blunt Meullenet-Owens Razor Shear (BMORS). Water properties were determined with low-field nuclear magnetic resonance (LF-NMR). Spearman correlation was used to estimate relationships between WB scores and water properties, while Pearson correlation was used for relationships between BMORS force and water properties. LF-NMR measurements exhibited 3 water components: protein-associated or hydration water T2b, intra-myofibrillar water or immobilized water T21, and extra-myofibrillar water or free water T22 in chicken breast meat. Significant and strong Spearman correlations were found between the WB scores and T21 time constant, the abundance (normalized areas) of T22, and the proportion of T21 and T22 (rs > 0.60, P < 0.001). Strong Pearson correlations (r = 0.72) were noted only between the T21 time constant and BMORS force. These results demonstrate that water may contribute to the specific texture characteristics measured with subjective WB scoring (palpable hardness and rigidity) and BMORS (hardness and share force) in raw broiler breast fillets with the WB condition.


Sujet(s)
Poulets , Viande , Muscles pectoraux , Eau , Animaux , Viande/analyse , Eau/analyse , Muscles pectoraux/anatomopathologie
19.
Anim Sci J ; 95(1): e13956, 2024.
Article de Anglais | MEDLINE | ID: mdl-38797661

RÉSUMÉ

Dry-cured beef ham quality is determined by moisture content; however, it is hard to do non-destructive monitoring. We investigated whether the internal moisture content of dry-cured beef ham could be determined from the impedance of the surface, which is removed at the time of eating. Supraspinatus muscle samples from Japanese Shorthorn steers were dried for different periods. The samples were then divided into the parts to be removed (surface) and edible parts. Their respective impedance and moisture content were measured, and the correlation between these two parameters was investigated. A negative correlation was observed between the impedance and moisture content of the surface and the shallow and deep sections of the edible part. There was also a negative correlation between the impedance of the surface and the moisture content of the shallow and deep sections of the edible part. Therefore, the results of this study indicate that during drying, the moisture content in the shallow and deep sections of dry-cured hams can be estimated by measuring the impedance of the surface. This non-destructive method of measuring the moisture content of dry-cured hams can help in regulating the moisture content during drying to produce high-quality dry-cured hams.


Sujet(s)
Impédance électrique , Qualité alimentaire , Eau , Animaux , Eau/analyse , Bovins , Dessiccation , Manipulation des aliments/méthodes , Produits carnés/analyse , Analyse d'aliment/méthodes , Suidae , Viande rouge/analyse , Mâle , Muscles squelettiques
20.
J Agric Food Chem ; 72(18): 10247-10256, 2024 May 08.
Article de Anglais | MEDLINE | ID: mdl-38683760

RÉSUMÉ

Some forage legumes synthesize phytoestrogens. We conducted a glasshouse study to investigate how water stress (drought and waterlogging) influences phytoestrogen accumulation in red clover and kura clover. Compared to the red clover control, the 20 day drought resulted in an over 100% increase in the phytoestrogens formononetin and biochanin A, which together accounted for 91-96% of the total phytoestrogens measured. Waterlogging resulted in elevated concentrations of daidzein, genistein, and prunetin but not formononetin or biochanin A. Concentrations of phytoestrogens in kura clover were low or undetectable, regardless of water stress treatment. Leaf water potential was the most explanatory single-predictor of the variation in concentrations of formononetin, biochanin A, and total phytoestrogens in red clover. These results suggest that drought-stressed red clover may have higher potential to lead to estrogenic effects in ruminant livestock and that kura clover is a promising alternative low- or no-phytoestrogen perennial forage legume.


Sujet(s)
Phyto-oestrogènes , Trifolium , Trifolium/métabolisme , Trifolium/composition chimique , Trifolium/croissance et développement , Phyto-oestrogènes/métabolisme , Phyto-oestrogènes/analyse , Eau/métabolisme , Eau/analyse , Isoflavones/métabolisme , Isoflavones/analyse , Sécheresses , Génistéine/analyse , Génistéine/métabolisme
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