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This study aims to clarify the influence of various root zone temperatures and fertilizer concentrations on the strawberry growth. The parameters were collected from the Jiangsu Province from 2021 to 2023. Nine hierarchy indices were applied to conduct analytic hierarchy process (AHP) and Criteria importance using intercriteria correlation (CRITIC). A combined hierarchy of indices was closely related to strawberry growth. These indices included the firmness, sugar acid ratio, soluble solid, single fruit weight, yield, fertilizer partial productivity (PFP), and water utilization rate (WUE). Technique for order preference by similarity to ideal solution (TOPSIS) was also used to evaluate the comprehensive growth evaluation system for strawberry. The result showed that the root zone heating shared a positive effect on the growth of facility strawberries. There was the more significant behavior, as the heating time increased. In the first crop, the highest content of soluble solid was observed under T1 treatment. Nevertheless, the low fertilizer concentrations (0.5 g/L) led to the highest single fruit weight among all three-temperature treatments. While the high fertilizer concentrations resulted in the smallest single fruit weight. The highest PFP was observed in the T8 treatment, indicating the significantly higher than the rest. In the second crop, the highest single fruit weight was observed under the low fertilizer concentrations, whereas the lowest was found under the high fertilizer concentrations. The highest yield and PFP were achieved under the T5 treatment, which was the higher than the rest. The highest WUE was also found under T5 treatment, which was significantly higher than that under T1, T2, T3, T4, T6, and T7 treatment. There was no significant difference, compared with the T8 and T9 treatments. In the third crop, the highest yield was achieved under the T5 treatment, which was significantly higher than that under T1 and T7 treatment. As such, the better performance was found in the medium fertilizer concentration at medium temperature. The single-factor effect analysis of root zone temperature and fertilizer concentration showed that the highest single fruit weight, PFP and WUE were found at a fertilizer concentration of 1.5 g/L. Therefore, the moderate concentration of fertilizer was optimized for the WUE and economic benefits. The highest yield, PFP and WUE were obtained at a root zone temperature of 16 ℃, followed by 22 ℃, and lowest under 8 ℃ (without heating). The moderate heating of root zone was effectively enhanced the root absorption capacity, while the excessively high temperatures of root zone presented an inhibitory effect. The multi-objective evaluation was obtained to optimize the quality, yield, PFP, and WUE in the strawberry production. The AHP and CRITIC were used to define the subjective and objective weights, in order to evaluate strawberry production, respectively. The weight was calculated and then ranked in the descending order of the yield, fruit weight, sugar acid ratio, PFP, soluble solid, WUE, and hardness. The TOPSIS indicated that the T5 (16 ℃, 1.5 g/L) shared the highest score among all treatments, followed by the T4 (22 ℃, 1.5 g/L) and T3 (non-heated, 2.5 g/L). The lowest score was found under the T7 (22 ℃, 2.5 g/L). A binary quadratic regression equation was also constructed for the growth control of facility strawberries, according to the root zone temperature and fertilizer concentration. Additionally, the equation was statistically significant at the significance level of 0.05. The bivariate quadratic regression equation was converted into a contour map of the comprehensive score of strawberry by root zone temperature and fertilizer concentration. Dividing the optimal closed loop interval of root zone temperature and fertilizer concentration coupling based on a comprehensive evaluation of more than 82%, the root zone temperature amount of 13.10-18.47 ℃ and the fertilizer concentration amount of 1.43-1.87 g/L were the most beneficial to strawberry growth. The findings can provide the theoretical reference to evaluate the relationship between root zone temperature and fertilizer, particularly for the precision management in strawberry production. [ABSTRACT FROM AUTHOR]

Abstract: Chinese cuisine with a rich history has a wide range of complex and various techniques. Among them, the oil stir-frying is characterized by a significant short, intense dynamic process. Numerical simulation is also required to explore the process mechanism of cooking quality formation. Mathematical models are crucial to simulate the food heat treatment, and then optimize and control the process. The reliability of these models can rely mainly on the accuracy of the parameters. The unsteady-state transfer of water mass includes the convective mass transfer, due to the macroscopic movement of fluid on the solid-liquid boundary during oil stir-frying. The parameter of this process is the surface mass transfer coefficient (hm), represented by the rate of mass transfer between the fluid and the surface of the food particles pmoisture diffusion coefficient (Deff) can indicate the speed of component diffusion in the medium. Specifically, Deff was a material transfer property that was determined by the random movement of internal water molecules after molecular diffusion and mass transfer. The hm and surface heat transfer coefficient between particle fluid and particle (hfp) between the particle and fluid can be referred to as the surface transfer coefficient. These parameters are closely related to the specific process. This study aims to investigate the effects of controllable operations and key process parameters on oil stir-frying cooking, in order to enhance the reliability and accuracy of numerical simulation. The hm and Deff of moisture were determined, according to the dimensionless analytical solution of moisture content during the oil stir-frying of pork tenderloin. A systematic investigation was made to analyze the effects of preheated oil temperature and specific surface area (Ω) on hm and Deff. Subsequently, a comparison was made on the effects of hm and hfp on cooking maturity. The maturity value theory was proposed using the mathematical model of heat and mass transfer in the oil stir-frying. The hm values ranged from 5.927 × 10-6 to 2.481 × 10-5 m/s, which were slightly higher than those reported in similar deep-frying studies. The Deff values and activation energy (Ea ) ranged from 6.281 × 10-9 to 4.148 × 10-8 m²/s and 24.2 to 30.6 kJ/mol, respectively. Furthermore, the preheating oil temperature and Ω had a significant effect on hm and Deff (P < 0.05). Higher preheated oil temperatures led to greater hm and Deff values, while the larger Ω values resulted in larger hm and smaller Deff values. Additionally, the hm value shared a minor impact on the cooking process, whereas the hfp was a crucial process parameter to control the cooking. The key parameters hm and Deff can be used to numerically simulate the heat and mass transfer in oil stir-frying. There were some effects of preheating oil and knife handling on hm and Deff during oil stirfrying. Additionally, the mechanisms of hm and hfp in the heat mass transfer can also be clarified during oil stir-frying. [ABSTRACT FROM AUTHOR]

Soil water movement can greatly contribute to the water flow with the soil profile in the engineering of sprinkler irrigation. In this study, a numerical simulation was proposed to explore the soil water movement under intermittent and continuous sprinkler irrigation using COMSOL software. The time variable and non-uniform infiltration boundary conditions were also utilized in the sprinkler irrigation. A series of experiments on soil tanks were conducted to validate the accuracy of the simulation. A comparison was made on the simulated and measured parameters, including the soil water content and downward vertical wetting front. Finally, a systematic investigation was applied to evaluate the effects of sprinkler irrigation and irrigation uniformity on soil wetting and soil water content. Sprinkler irrigation was verified by four patterns (continuous, intermittent 1, 2, and 3) and three uniformity coefficients of sprinkler irrigation (39.77%, 59.87% and 80.15%). The results showed that the COMSOL simulation was used to accurately simulate the soil wetting patterns in sprinkler irrigation. The root mean square error and the coefficient of residual mean square error values were less than 0.014 and 0.017 cm³ /cm3 , respectively, between the calculated and measured soil water contents at 72 h after the sprinkler irrigation. The coefficient of determination R² value was higher than 0.961. There were higher movement speeds of the soil wetting front and the soil water contents of the wetted zone from 0 to 12 h after the irrigation, indicating the slow-down trending, as time passed. There were no significant effects of sprinkler irrigation patterns on soil water movement and soil water content uniformity. The water content of surface soil decreased, as the intermittent frequency and duration increased, while the water infiltration depth increased after the sprinkler irrigation. Meanwhile, the soil water content decreased with the increasing intermittent frequency and duration at 72 h after the end of irrigation. Christiansen uniformity coefficient was used to evaluate the uniformity of soil water content after simulation. The soil water content uniformity coefficient was higher than the uniformity coefficients of sprinkler irrigation, according to the initial surface-measured distribution. The soil water content uniformity coefficient of shallow-layer soil increased, as time passed, while that of the deeper-layer soil decreased. The soil water content uniformity coefficient at the soil depth of 10 cm was selected to represent the uniformity of soil water content. The soil water content uniformity coefficient increased with the increasing uniformity coefficients of sprinkler irrigation. Furthermore, the soil water content uniformity coefficient values were 88%-90% under the continuous and three intermittent sprinkler irrigations, when the uniformity coefficients of sprinkler irrigation ranged from 40% to 60%. Once the uniformity coefficients of sprinkler irrigation increased to 80%, the soil water content uniformity coefficient values increased higher than 94%. The research space was provided to reasonably reduce the design uniformity coefficients of sprinkler irrigation in sprinkler irrigation. In the low uniformity of sprinkler irrigation, there were high rates of peak water application and a large total irrigation amount using intermittent sprinkler irrigation. The intermittent frequency and duration can be expected to reduce the risk of surface runoff and deep percolation, thus improving the uniformity of soil water content [ABSTRACT FROM AUTHOR]

Copyright of Transactions of the Chinese Society of Agricultural Engineering is the property of Chinese Society of Agricultural Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Transactions of the Chinese Society of Agricultural Engineering is the property of Chinese Society of Agricultural Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Transactions of the Chinese Society of Agricultural Engineering is the property of Chinese Society of Agricultural Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

根系是土壤层中重要的组成结构, 根土环境影响田间作物生长发育. 为探究作物根系对农地土壤水分空间运动 异质性的影响, 进一步反映根土环境对农业生产的作用, 该研究以辣椒为试验作物, 于 2022 年 9 月 20 日—2022 年 9 月 23 日开展野外染色示踪试验, 结合形态学图像解析技术与灰色系统理论, 对作物根系影响下的农地土壤水分空间运 动变化进行分析. 结果表明：辣椒根系接近鱼尾形结构, 根系体积相对较大, 根系扎根深度和根系广度 (根系形态) 与 根系结构相关程度高 (P＜0.05) . 在相同外部供水条件下, 非根区的水分整体分布在田间土壤表层 (平均狭长度为 0.89), 而根区土壤水分在整个土壤深度 (0～50 cm) 空间内沿深度由整体向团状聚集状态再向“指状” (平均狭长度 为 0.61) 形态转变. 非根区和根区的土壤平均染色面积比均随土壤深度增加而减小, 但根区平均染色面积比 (36.84%) 显著高于非根区 (23.62%), 土壤水分分布更集中. 非根区水分沿土壤深度的增加, 其运动变化程度 (平均湍动强度 为 116.09) 显著高于根区 (P＜0.05), 在根系的影响下, 水分竖向入渗能力较强. 相较于根系结构, 根系形态对土壤 水分运动影响更显著, 其中比根长对土壤水分湍动强度影响最大 (灰色关联度为 0.984) . 可见, 田间根系周围的土壤 水分运动较活跃, 根系的作用能增加其下方土壤水分的入渗能力, 研究为提高辣椒水分利用效率提供理论支撑. [ABSTRACT FROM AUTHOR]

Copyright of Transactions of the Chinese Society of Agricultural Engineering is the property of Chinese Society of Agricultural Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The objective of this study was to develop an efficient non-enzymatic electrochemical sensor for H2O2 detection in milk using the catalytic reduction of H2O2 on ZnFeCoO4. Firstly, ZnFeCoO4 derived from ZnCo2O4 by the partial substitution of Co with Fe was synthesized via sol-gel combustion. In ZnCo2O4, 1 mmol Zn(NO3)2·6H2O and 2 mmol of Co(NO3)2·6H2O were dissolved in a nitric acid solution (2mL of nitric acid, and 30ml of distilled water). The sticky gel was subsequently obtained by adding 15 mmol citric acid and stirring for 5 h in the oil bath at 90℃. After that, the gel was placed in a 170℃ oven (10℃/min heating rate) for 12 hours. Then, the moisture-removed gel was crushed with a mortar. Finally, the powder was calcined in a 600 ℃ tubular furnace (5℃/min heating rate) for 6 hours to obtain the spinel phase ZnCo2O4 powder. The preparation process of ZnFeCoO4 was consistent with that of ZnCo2O4. The only difference was that the 2 mmol of Co (NO3)2·6H2O was replaced with 2 mmol of Fe(NO3)2·6H2O. Transmission electron microscopy, X-ray diffraction, and X-ray photoelectron spectroscopy were used to characterize the crystal structure and morphology of the catalyst, while cyclic voltammetry (CV) was used to study the electrochemical performance of the electrode. In order to verify the effectiveness of the ZnFeCoO4 electrode in detecting H2O2 content in milk, the milk from the local supermarket was centrifuged and 1 mL supernatant was dissolved in 10 mL PBS (pH 7.4). Standard addition was used for the recovery experiment. The results showed that a similar morphology was obtained after the partial or complete replacement of Co with Fe. ZnFeCoO4 presented a better crystal shape and high consistency with the standard database card JCPDS No.23-1390. The mass ratios of Zn, Co, and Fe were measured as 31.46%, 35.77%, and 27.15%, respectively, and the molar ratio was about 1:1.2:1, which roughly met the chemical expression of the compound. The XRD patterns of ZnCo2O4 and ZnFeCoO4 showed that the diffraction peaks of ZnFeCoO4 were basically the same as those of ZnCo2O4, both of which were conformed to the standard database card JCPDS No.23-1390, indicating the spinel phases. In addition, the diffraction peak of ZnFeCoO4 was shifted to a smaller angle than that of ZnCo2O4, because the lattice radius of Fe3+ was slightly larger than that of Co3+. This proved the successful synthesis of spinel phase ZnFeCoO4. The CV analysis showed that the ZnFeCoO4 presented better catalytic activity than the ZnCo2O4, where the electrochemical sensor using ZnFeCoO4 shared the better electrocatalytic performance for H2O2 with a theoretical detection limit of 0.5 μmol/L. There was a linear relationship between the concentration of hydrogen peroxide and the peak reduction current in the range of 0.5-2.5 mmol/L, where the determination coefficient (R²) is 0.989. The stability and selectivity of ZnFeCoO4 electrode analysis showed that there was no significant change in the current density when the electrode was exposed to 1mM H2O2 solution for 30 days. After one month, the observed current density was about 92.7% of the original current density, with a relative standard deviation of 13.2%, indicating the better stability of the ZnFeCoO4 electrode. The amperage method was implemented to evaluate the effect of ascorbic acid, glucose, sucrose, citric acid, urea, and H2O2 on the current density response. Except for H2O2, there was no significant change in the current density, indicating the better selectivity of the sensor. In addition, the sensor also presented excellent reproducibility for H2O2. Excellent recoveries from 98.60% to 101.23% were obtained for the H2O2-spiked milk. The as-presented sensor can be expected to serve as a promising candidate for the H2O2 determination in food safety. [ABSTRACT FROM AUTHOR]

The objective of this study was to evaluate the effect of dietary probiotic supplementation on protein synthesis and flavor compounds in lambs. Two experimental groups were randomly allotted for the 18 three-month-old crossbred ewes of Dorper × Small-Tailed Han sheep. The control group was fed a basic diet, and the probiotic group was supplemented with Clostridium butyricum at 5 g/head on the basis of the control diet (the viable number of Clostridium butyricum was 5.0×108 CFU/g). The pre-feeding was set as 7 days, and the feeding period lasted for 90 days. After that, the selected lambs were transported into the abattoir for slaughter, where the longissimus dorsi muscle was immediately dissected and weighed after slaughter. One part of the muscle samples were stored at -80 ℃ for the determination of enzyme activity and gene expression that related to protein synthesis, and another part was stored at -20 ℃ for the determination of flavor substances. Muscle weight, flavor substances, muscle fiber morphology, enzyme activities, and the expression of protein synthesis genes were determined by gas chromatography mass spectrometry (GC-MS) and real-time fluorescent quantitative polymerase chain reaction (RT-qPCR). The results demonstrated that compared with the control group, the weight of longissimus dorsi muscle in the probiotic group increased significantly (P<0.05), while the diameter and cross-sectional area of muscle fibers increased significantly (P<0.01), indicating that the probiotics were enhanced the muscle weight of lambs. The activity of branched chain aminotransferase (BCAT) and branched-chain α-keto acid dehydrogenase (BCKDH) significantly increased in the muscle of the probiotic group (P<0.05), indicating that the dietary supplementation with probiotics accelerated greatly the metabolism of branched-chain amino acids in lambs. The gene expressions of insulin-like growth factor 1 (IGF-1), protein kinase B (Akt1), mammalian target of rapamycin (mTOR), p70 ribosomal proteinS6 kinase (p70S6K), and eukaryotic translation initiation factor 4E binding protein 1 (4EBP1) in the probiotics group were higher than those in the control group (P<0.05), whereas, the gene expressions of forkhead box protein o3 (FoxO3) and muscle atrophy F-box (MAFbx) were significantly lower than those in the control group (P<0.05). There was no significant difference in the muscle ring-finger protein-1 (MuRF1) gene expression between the two groups (P>0.05). It was confirmed that the probiotics promoted protein synthesis, but inhibited the protein degradation of lambs, when increasing the gene expressions of Akt1, mTOR and p70S6K, and reducing the gene expressions of FoxO3 and MAFbx via the Akt signaling pathway. There was some influence of dietary probiotic supplementation on the composition and relative contents of flavor compounds in lambs. Compared with the control group, the content of hexanal, heptanal, nonanal, and decanal were significantly reduced in the probiotic group (P<0.05), whereas, the content of 1-octanol and 1-octen-3-ol increased significantly (P<0.05). Octanal, nonanal, (E)-2-nonenal, decanal, (E)-2-decenal, dodecanal, 1-octen-3-ol, and phenol greatly contributed to the formation of lamb flavor in the probiotic group, imparting fruit-like, onion-like, sweet, mushroom, grassy and rose-like flavors. Correlation analysis showed that there was a correlation between the critical flavor substances and protein synthesis-related indicators, in which the gene expression of IGF-1 was significantly negatively correlated with the (E)-2-nonenal, decanal and (E)-2-decenal (P<0.05), while positively correlated with the 1-octen-3-ol (P<0.05). The gene expression of Akt1 was negatively correlated with the (E)-2-nonenal (P<0.05). In conclusion, the addition of probiotics into the diet can be expected to improve the protein synthesis level of lambs through the Akt signaling pathway, which in turn affected the flavor of lamb. The finding can also provide a theoretical basis and reference to regulate the quality of lamb via the diet. [ABSTRACT FROM AUTHOR]

Copyright of Transactions of the Chinese Society of Agricultural Engineering is the property of Chinese Society of Agricultural Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Soil Cadmium (Cd) has posed a great threat to ecological security and human health in recent years. The exposure under the direct oral ingestion of contaminated soils has been the main contributor of Cd to the human body. The immobilization is an advisable technology to reduce the activity and bioavailability of Cd for the remediation of the Cd-contaminated soil. However, several challenges still remain for conventional immobilizing agents, such as the limited and weak immobilization mechanism, low efficiency and stability. Fortunately, layered double hydroxides (LDHs) can be a new promising type of functional material with great adsorption capability on heavy metals. But, only a few studies were focused on the application of soil remediation, regardless of the potential application to the health risk of soil Cd. In this comparative study, two conventional immobilizing agents (Ca(OH)2 and Ca(H2PO4)2) and one promising LDH (hydrocalumite, CaAl-Cl LDH) were used to remediate the soils with Cd contamination. Four typical soils (red soil, brown soil, cinnamon soil, and black soil) were collected from the cities of Fuzhou, Beijing, Nanjing, and Gongzhuling in China, and then artificially contaminated to the Cd concentration of 180 mg/kg. Subsequently, the three immobilizing agents were applied on the land under the pre-determined optimal patterns. Specifically, the mass ratios of Cd to the immobilizing agent were 1:100, 1:500, and 1:1 000, respectively. A comprehensive analysis was also made to determine the effects on the specific soil physicochemical property (soil pH), Cd fractionation (ecological risk), and oral bioaccessibility of soil Cd (health risk) after three-month immobilization. The relevant mechanisms were further explored. Note that there was no evaluation of the health risk of soil Cd using the total concentration of Cd in the soil, due to the overestimation. Furthermore, the Cd bioaccessibility was utilized from the advanced in vitro test, where a PBET model was modified referring to the IVG model. An accurate simulation was then achieved in the digestion processes in the human gastrointestinal tract. Results showed that the soil pH increased greatly after the CaAl-Cl LDH remediation, further facilitating the Cd immobilization. In terms of Cd fractionation in soil, the Ca(OH)2, Ca(H2PO4)2, and CaAl-Cl LDH all significantly reduced the mobility factor of soil Cd (i.e., the proportion of exchangeable and carbonates-bound Cd fractions to the total Cd), with an average decrease of 16.1%, 56.9%, and 29.2%, respectively. As such, better capabilities were obtained to reduce the crop uptake of soil Cd and the ecological risk to the ambient environment. More importantly, the CaAl-Cl LDH more effectively reduced the oral bioaccessibility and the health risk of soil Cd, compared with the rest. The average decrease was 19.2% in the gastric phase, which was 3.11 and 1.99 times those of Ca(OH)2 and Ca(H2PO4)2, respectively. Besides, the decrease was 33.0% in the small intestinal phase, which was 5.99 and 2.72 times those of the conventional. A series of mechanisms were also proposed for the Cd immobilization, including surface complexation, interlayer anion exchange-adsorption, dissolution-precipitation, and isomorphous substitution. Therefore, the CaAl-Cl LDH demonstrated great potential to immobilize the soil Cd in a super-stable manner. It is also highly expected for wide application in real cases. Anyway, the finding can provide a scientific basis and valuable reference for the development, improvement, and selection of the immobilization agents/technologies, in order to better remediate the Cd-contaminated soils. [ABSTRACT FROM AUTHOR]

Copyright of Transactions of the Chinese Society of Agricultural Engineering is the property of Chinese Society of Agricultural Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Transactions of the Chinese Society of Agricultural Engineering is the property of Chinese Society of Agricultural Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Leaf Area Index (LAI) is closely related to crop transpiration, photosynthesis, and final yield. Fast, non-destructive, and accurate monitoring of the winter wheat LAI during the critical growth period is an important way to accurately grasp crop canopy structure, growth information, above-ground biomass, yield, and pests. In the past, most of the estimated data of LAI were inverted by ground spectrum, Unmanned Aerial Vehicle (UAV) multi-spectrum, and satellite multi-spectral remote sensing data. In this study, a low-altitude unmanned aerial vehicle platform and an imaging spectrometer were used to obtain hyperspectral remote sensing images of jointing winter wheat in Xianyang city, Shaanxi province, China. The first derivative and continuous spectrum removal spectrum were used to transform the original canopy spectrum at 450-950 nm to extract any two frequency bands Specific. The Ratio Spectral Index (RSI), Differential Spectral Index (DSI), and Normalized Spectral Index (NDSI) were constructed respectively. Combining a narrow-band spectral index, a univariate regression analysis was performed on the best nine narrow-band spectral indices of a class, the original canopy spectrum, the first derivative spectrum, and the three best combinations spectra of any two bands under the continuous spectrum removal spectrum. The index was modeled using multiple linear regression. Two machine learning algorithms (BP neural network and random forest) were used to model a total of nine best narrowband spectral indices under three transformations. By comparing the coefficient of determination, the root mean square error, and the residual prediction deviation, the best estimation model of winter LAI was selected. The results showed that spectral transformation significantly improved the correlation between spectral variables and LAI, and the position with a higher correlation was mainly located in the red edge area. The correlation between the optimal narrow-band spectral index extracted based on the first derivative transform spectrum and the continuous spectrum removal transform spectrum and LAI was nonlinear, which was more suitable for fitting a quadratic function of a variable. Compared with the unary regression model, the accuracy of the multiple linear regression model based on the multi-spectral index was not significantly improved. However, both the multiple regression model and the unary linear regression model showed that the accuracy of the model based on the continuous spectrum transformation spectrum was higher than the accuracy of the model under the original spectrum and the first derivative transformation spectrum. It showed that the continuum removal method was used to transform the spectrum and used for modeling, and the NDSI (738,822) index based on the continuous removal spectrum had a good LAI estimation ability. Compared with the traditional regression model, the accuracy of the BP neural network model and the random forest regression model constructed with the 9 best narrowband spectral indices as independent variables had been significantly improved. Among them, the random forest regression model had the highest accuracy, because the random forest algorithm modeling could well tolerate some noise and outliers. As long as the parameters were adjusted accurately, overfitting was less likely to occur, and it was more suitable to solve certain nonlinear problems. Based on this model, the spatial distribution of the LAI of winter wheat at the jointing stage in this study area was basically in line with the actual situation, and the LAI estimation accuracy based on the narrow-band spectral index, and random forest algorithm was the highest (the residual prediction deviation was 2.01, the coefficient of determination was 0.77, the root mean square error was 0.27), which could be used as a basic model for hyperspectral remote sensing estimation of winter wheat UAV at jointing stage. The basic model could realize the LAI remote sensing mapping of a small area. It could provide a theoretical basis for later crop growth and variable fertilization. [ABSTRACT FROM AUTHOR]

Copyright of Transactions of the Chinese Society of Agricultural Engineering is the property of Chinese Society of Agricultural Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The accurate measurement of sediment concentration in collecting tanks of slope runoff plots is a key to quantitatively monitor slope soil erosion. The researches on measuring accuracy, influencing factors and applicability of field runoff plot observation methods are needed. In this study, four methods of sediment concentration were compared. The test was taken in quaternary red earth. The soil samples were taken from surface of farmland (0-20 cm). Six sediment concentrations (1.05, 5.07, 10.49, 50.72, 101.45 and 439.10 kg/m³) were designed based on the measured sediment concentration range from 2012 to 2016 in slope farmland. Three water depths were set up including 30, 60 and 90 cm. Four methods included Artificial Method (AM), Mechanical Method (MM), Dept Profile Method (PM) and MM+PM. The measurement accuracy was evaluated by relative error. Each treatment was replicated three times. The results show that compared with the true value, the measurement accuracy of different method for determining sediment concentration was low. The averages of absolute relative error for the AM, MM, PM and MM+PM were 37%, 24%, 38% and14%, respectively. The measurement accuracy of different methods was 14% or above. Among them, the accuracy of MM+PM was the highest. In general, the relative error of each method was large under the condition of high sediment concentration. The depth of water had different influence on different sampling methods. Comparatively, the measurement error of AM was most significantly affected by water depth. Under low sediment concentration, when the water depth increased to 60 cm, the measurement error significantly increased, but when the water depth continued to increase, the measurement error did not increase. When the sediment concentration was 101.45 kg/m³, the relative error of MM only increased significantly after the water depth increased to 90 cm. When the sediment concentration was 59.72 kg/m³, no obvious relationship was found between the measurement accuracy of the PM method and the water depth. When the sediment concentration was more than 5.07 kg/m³, the measurement accuracy of the MM+PM method was almost not affected by water depth. The linear equation was used to modify the sediment concentration measurement results of the four methods. All R² were greater than 0.99 (P<0.01), and the root-mean-square error was 4.53-11.37 kg/m³, which indicated the reliability of the linear regression equation and the equation could be used to calibrate the measured values of each method. The relative error of the measured values of each method was significantly reduced and the measurement accuracy was significantly improved. The practical range of these equations was 1.05-439.10 kg/m³ and the water depth was 60 cm. The results of this study could support the selection of sampling methods under different conditions. The results of this study could be used to revise the sediment concentration in collecting tanks of slope runoff plots in red soil area. [ABSTRACT FROM AUTHOR]

Copyright of Transactions of the Chinese Society of Agricultural Engineering is the property of Chinese Society of Agricultural Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Transactions of the Chinese Society of Agricultural Engineering is the property of Chinese Society of Agricultural Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Transactions of the Chinese Society of Agricultural Engineering is the property of Chinese Society of Agricultural Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Transactions of the Chinese Society of Agricultural Engineering is the property of Chinese Society of Agricultural Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Transactions of the Chinese Society of Agricultural Engineering is the property of Chinese Society of Agricultural Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Transactions of the Chinese Society of Agricultural Engineering is the property of Chinese Society of Agricultural Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Transactions of the Chinese Society of Agricultural Engineering is the property of Chinese Society of Agricultural Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Transactions of the Chinese Society of Agricultural Engineering is the property of Chinese Society of Agricultural Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Transactions of the Chinese Society of Agricultural Engineering is the property of Chinese Society of Agricultural Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Transactions of the Chinese Society of Agricultural Engineering is the property of Chinese Society of Agricultural Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The surface and subsurface runoff in the red soil slope farmland result in soil moisture and nutrient loss. In addition, the surface and subsurface runoff are important components contributing runoff at the watershed scale. An extensive literature shows that rain intensity and slope are two main factors playing an important role in the surface and subsurface runoff. In this paper, the surface and subsurface runoff in the red soil slope land under different rainfall intensities and slopes were studied by stimulated rainfall experiments in the flume (3.0 m length×1.0 m width×0.5 m depth) with variable slopes. The experiments were conducted in the Jiangxi Soil and Water Conservation Ecological Science and Technology Park. Stratified soil samples from different profiles including 0-20 cm (the plow horizon) and 20-40 cm (the plow pan) were collected and then filled respectively into the flumes by controlling the bulk density. For the rain intensity of 90 mm/h, we set four slopes including 5°, 10°, 15° and 20° in the simulated rainfall experiment. Three rain intensity levels (30, 60 and 90 mm/h) were set for the plots with slope of 10°. The results indicated that: 1) the subsurface runoff lagged behind the surface runoff, and the initiation time of the surface and subsurface runoff decreased with the increase of rainfall intensity from 30 mm/h to 90 mm/h. The lag time of the subsurface runoff initiation increased with the increasing rain intensity, and then tended to be stable; 2) the initial and steady surface runoff increased with the increase of the rain intensity; and the initiation subsurface runoff intensity increased with the increase of rainfall intensity. An increase trend was observed in the runoff produced by per unit rainfall; 3) the initial intensity of the surface runoff increased with the increase of rainfall intensity from 30 to 90 mm/h. However, no significant differences were found for the peak values of the subsurface runoff under different rainfall intensities. The attenuation curves of the surface runoff under different rainfall intensities were similar; 4) the obvious differences were observed between the runoff process curves of the surface runoff and subsurface runoff. The surface runoff increased firstly and then tended to be stable, but the soil subsurface runoff increased firstly and then decreased; 5) the initiation time of the surface runoff decreased with the increase of slope from 5° to 20°, but the initiation time of the subsurface runoff decreased firstly and then increased with the increase of the slope. The lag time of the subsurface runoff to the surface runoff also decreased firstly and then increased with the increasing slopes; 6) the surface runoff intensity first increased and then decreased with the increasing slope from 5° to 20° with a critical slope of 10°. The peak values of the subsurface runoff in soils increased firstly and then decreased with the increasing slopes. Moreover, the time to reach the peak value of the subsurface runoff decreased gradually with the increase of the slopes. [ABSTRACT FROM AUTHOR]

Copyright of Transactions of the Chinese Society of Agricultural Engineering is the property of Chinese Society of Agricultural Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

High weathered soils in arid and semi-arid area are characterized by low soil fertility and high erosion potential. This paper evaluated the influences of nano-carbon on soil erosion and water loss on the sloping land (15°) of the Chinese Loess Plateau. Simulated rainfall experiments were performed on a natural, fallow loessial slope in the Shenmu Erosion and Environment Research Station, Institute of Soil and Water Conservation, Chinese Academy of Sciences, which locates in the Liudaogou watershed, Shenmu County, Shaanxi Province. Five application rates (i.e., 0, 0.1%, 0.5%, 0.7%, and 1.0%) of nano-carbon were selected during the simulated rainfall experiments (rainfall intensity of 60 mm/h); and 4 vegetation species (i.e., caragana, alfafa, bean, and maize) were planted on the slope to evaluate the vegetation effect on soil and water conservation with the bare as the control. A constant-intensity rainfall method was adopted under natural conditions. Field plots were established on the slope that had been fallow for 5 years. The rainfall simulator came from the independent design of Xi'an University of Technology. Under the 60 mm/h rainfall intensity, the simulated rainfall experiments were carried out for 50 times in the 25 different pretreated plots in order to estimate soil erosion and water loss for all the treatments. The main results were as follows: the initial runoff time was delayed with the increase of nano-carbon contents. Compared to the control treatment without nano-carbon application in bare land, the initial runoff time in alfalfa plot was delayed by 287.1%, which was the most obvious. Furthermore, with the increase of nano-carbon contents, the runoff in each treatment decreased obviously. The nano-carbon alfalfa coverage also had the most obvious effect in the reducing runoff, and the runoff was reduced by 66.47%; for other vegetation species, the reduction was between 31.5% and 33.6%. Moreover, the nano-carbon had a significant effect on soil loss controlling. The nano-carbon in alfalfa land showed the best effect for soil loss controlling, which was followed by caragana. Soybean land showed the highest soil loss. For the bare land (control) and alfalfa coverage, when the nano-carbon content was 1%, the lowest sediment yield was obtained; while for caragana, soybean and maize coverage, when the nano-carbon content was 0.5%, the sediment yield was the lowest. Based on the correlation analysis between nano-carbon and runoff and sediment yield, it could be concluded that nano-carbon has a significant impact on the experimental results. In the evaluation of soil and water loss control effect, the 0.5% nano-carbon had the obvious effect, which was similar with the 0.7% and 1.0% nano-carbon content, so considering the price, 0.5% nano-carbon content was appropriate on soil and water loss control in loess area. The results provide a guide for controlling soil water and nutrient loss on the sloping land. [ABSTRACT FROM AUTHOR]

In the implement of water transfer project, it is essential to build the joint distribution model of low flow between the inflow and outflow region and to analyze the risk of water shortage or the assurance of water resources in the outflow region when water shortage occurs in the inflow region. In the paper, the goodness-of-test approach based on the Cramervon Mises statistics of the Rosenblatt transfer was applied for modeling bivariate joint distribution. The analysis of change point and the method of mean shift were used for reconstruction of time series of low flow. Joint distribution modeling of low flow between the inflow and outflow regions of the Project of West-to-East Water Transfer of the Pearl River Delta was built. According to the predefined thresholds set by the instream ecological flow and the lowest flow of water demand, individual and joint risks of water shortage in the inflow and outflow regions and their alterations under changing environment were investigated. Results demonstrated that Archimedean copulas, i.e. Clayton, Frank and Gumbel-Houggard models were better for modeling the joint distribution of low flow between the inflow and outflow regions. The change point of the low flow in the inflow region occurred in 1972, but there was no difference in the selection of copulas and their parameters on modeling the joint distribution of the inflow and outflow regions, regardless of using any one of the reconstructive time series, namely the forward and backward returned series. The lowest monthly stremflow in terms of mean value increased by 65.5% under changing environment, in particular the regulations of water reservoirs in the inflow region. In consequence, individual risks of water shortage in the inflow region and joint risks between the inflow and outflow regions remarkably decreased. However, the risk rate still accounted for 37.7% provided that the instream flow fulfilled the water demand in the inflow region. Though the joint risk rate decreased from 35.8% to 16.7% associated with the regulation of water reservoirs in the inflow region, the assurance rate decreased from 54.8% to 21.0% due to the positive dependence of low flow between the inflow and outflow regions. As water shortage in the inflow region was known, the assurance rate of water resources by 55.8% in the outflow region was slightly greater than its risk rate of water shortage (44.2%). In addition, the risk rate of water shortage in the outflow region accounted for 38.2% in case of maintaining its instream flow. Thus, it needs to be poured more attention how the specific regime of water resources regulation is put forward for the operation of the Project of West-to-East Water Transfer of the Pearl River Delta in the future, even though much more water in the outflow region than in the inflow region. [ABSTRACT FROM AUTHOR]

The closed greenhouse is a light-permeable greenhouse type, with totally-enclosed architectural structure. Cooling by ventilation is replaced completely by mechanical cooling. Excess solar energy is collected and stored to be reused to heat the greenhouse or other buildings. The closed greenhouse can achieve energy conservation and emission reduction, recycling water of evapotranspiration, maintaining a high level of CO2 concentration, as well as isolating the bacteria spores from external environment, etc. However, high air temperature inside the closed greenhouse is difficult to control effectively in summer, or a great deal of energy is needed to consume, resulting in a restriction of the closed greenhouse when used in actual production. In order to decrease air temperature inside the closed greenhouse, taking low carbon emission and energy-saving into consideration, a closed greenhouse with water-walls (CGWW) was designed and built in Changping District of Beijing, China. With an indoor ground surface of about 7.6 m2, it was supported by a steel skeleton and assembled from some glass tanks filled with water. And for suppressing the growth of green algae, pH value of the water was adjusted to 9.5. Water layer thickness of side walls and roof were 30 and 13 cm, respectively. Cooling characteristics of the CGWW in summer was tested from 26 Jul. to 10 Sep. 2015. During the test, cucumbers and rapes were cultivated inside the CGWW. The results showed that, average air temperature inside the CGWW was 29.4-34.3°C around noon (10: 00-16: 00), decreased by 0.8-6.8°C compared with ambient. Meanwhile, the air temperature drop range inside the CGWW got bigger with the increase of solar radiation or ambient air temperature (P＜0.01). In 94.6% of the photosynthesis period (06: 00-18: 00), air temperature inside the CGWW was controlled within 35°C, which could avoid the high temperature stress effectively. So the CGWW had remarkable effect for cooling in summer. During the nighttime, relative humidity inside the CGWW was controlled within 80%, and the average value was 54.7%-73.7%, decreased by 7.2%-17.5% compared with ambient. Meanwhile, there was a negative linear correlation between humidity difference and temperature difference, inside and outside the CGWW (P＜0.01). During the daytime, solar radiation in horizontal direction inside the CGWW was 31.5-67.4 W/m2, and accounted for 11.9%-17.8% of that outside the CGWW. As solar radiation transmitted into the CGWW from outside, ratio of far-red light decreased from 41.9% to 9.2%, with a transmittance of 6.0%, which was conducive to the suppression of high temperature inside the CGWW. Red and blue light had the most ratios and accounted for 23.9% and 27.1% of the spectrum distribution inside the CGWW, respectively, and both of them had an increase compared with outside. And red and blue light had transmittances of 32.4% and 37.5%, respectively, which were far higher than both UV-A and far-red light. Due to the selective permeability of the water-walls for solar spectrum, obviously, high temperature inside the CGWW could be controlled while adequate photosynthetically active radiation could be ensured. In addition, the CGWW showed some of regularity in distributions and daily variation of water-walls temperature and air temperature inside the CGWW. In summary, the CGWW which can obtain an ideal cooling effect, suitable humidity and illumination conditions via its own structure, has been proved to be a feasible, low carbon and energy saving greenhouse type, and will provide a reference and technical supports for the development of closed greenhouses. [ABSTRACT FROM AUTHOR]

In soil and water losses, 30% is from sloping cropland in China. Nutrients losses with soil losses cause poor soil productivity, especially in red soils. This study aimed to investigate the sediment and runoff losses of sloping cropland of quaternary red soil and the N and P losses in the sediments and runoff. Site-specific long-term observations have been conducted during June-October 2011 in the plots of quaternary red soil in Soil and Water Conservation Eco-technology Garden of Jiangxi （E15°42′38″-115°43′06″E, N29°16′37″-29°17′40″）located in De’an county, Jiujiang city, northern Jiangxi province. Four treatments such as bare land, downslope tillage, downslope tillage combined with hedgerow and transversal slope tillage were designed. Runoff, sediments and N and P contents were determined by collecting samples during every rainfall. The results showed that the surface runoff of bare land (15.96 mm) was highest, followed by downslope tillage (7.91mm) and downslope tillage+ hedgerow (6.64 mm) and transversal slope tillage (2.95 mm) was lowest. Compared with downslope tillage, runoff was reduced by 62.71% by transversal slope tillage. Sediment yields of bare land (2205.5 t/km2) was highest, followed by downslope tillage (584.6 t/km2) and downslope tillage+ hedgerow (410.7 t/km2), and the sediment yields of transversal slope tillage (99.96 t/km2) was lowest. Compared with downslope tillage, sediment yields of transversal slope tillage was reduced by 82.9%. The soluble N, ammonia nitrogen, nitrate nitrogen and soluble P losses in runoff were highest for bare land, and lowest for transversal slope tillage. They in the transversal slope tillage were reduced by 53.69%, 50.84%, 46.15% and 57.47%, respectively than those in downslope tillage. The total N, total P, alkali-hydro N and available P losses in sediments were highest in the bare land but lowest in sediments of the transversal slope tillage. The organic N losses from the sloping cropland were dominated by the soluble N; while inorganic N losses were dominated by ammonia N. Moreover, the P losses in sediments accounted for most of total P losses. The study is helpful for better understanding of nutrient losses from the sloping cropland of quaternary red soil, and provide data support for protection and regulation of soil and water losses and non-point pollution from sloping cropland. [ABSTRACT FROM AUTHOR]