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Data from national meteorological stations in 90 counties of Jiangxi province during 2012-2021 and 8 microclimate stations in rice fields during 2017-2021 were used to analyze the differences in temperature between rice fields and stations, and the statistical results based on H1 (NS)(daily max temperature of national stations ≥35 °C), H1 (RS)(daily max temperature of rice fields ≥35 °C), H2 (NS)(daily max temperature of national stations ≥37°C) and H2 (RS) (daily max temperature of rice fields ≥ 37 °C ) were compared. Furthermore, proposing high-temperature damage indicators more suitable for early rice in Jiangxi, which would promoting capabilities of high-temperature monitoring and defense. The results showed that: (1) compared with the national stations, the rice fields had a cooling effect, and the Tmax(daily maximum temperature), T(daily average temperature), and Tmin(daily minimum temperature) were 0.6 °C, 0.4 °C, and 0.3 °C lower than national stations. What's more, the cooling effect increased with the growth of early rice, which showed as heading-maturity period>transplanting-booting period>sowing-transplanting period. (2) The cooling effect was higher in sunny days than in cloudy and rainy days during the high temperature period, and T, Tmax and Tmin of early rice field were 0.7 °C, 0.8 °C and 0.6 °C lower than that of the national stations. On cloudy and rainy days, the decrease in temperature of rice fields was similar. (3) There were significant differences in daily and hourly air temperature between 6 rice fields and the corresponding national stations during H1 (NS) heat damage occurred, and the cooling intensity of the rice field was greater at night than in the daytime. The Tmax, T and Tmin of the 6 fields were generally about 1.2 °C lower, which was strongest in Jinxi filed with T, Tmax and Tmin was 1.5 °C, 1.1 °C and 2.6 °C lower. (4) H1 (NS) was the largest and H2 (RS) was the smallest in terms of the number of counties affected by heat damage, the average duration, the average yield reduction simulation value of affected counties and the simulation value of the whole in recent 10 years based on different heat damage index. There was no significant difference in the result of average duration, the simulated average yield reduction rate of affected counties, and the simulated yield reduction rate of the whole based on H2 (NS) and H1 (RS), while they were all different with the result based on H1 (NS) or H2 (RS). And the simulated value of the reduction rate of the whole calculated by H2 (NS) was closer to the actual value. Therefore, national stations Tmax ≥37°C was more suitable as an index of heat damage for early rice in Jiangxi. [ABSTRACT FROM AUTHOR]

The seasonal temperature forecasting models in greenhouse based on multiple regression (MR), BP artificial neural networks (BPANN), random forest (RF) and support vector machine (SVM) were constructed using meteorological observations inside and outside the Venlo-type glass greenhouses from 27th February 2021 to 4th March 2023 at Nanjing University of Information Science & Technology, and then to validate all the models. The results showed that the fitting accuracy of the seasonal forecasting models for daily average and minimum air temperatures in the greenhouse was significantly higher than that of the seasonal forecasting models for daily maximum air temperature; the fitting accuracy of each model for air temperature inside the greenhouse in spring, summer and autumn was higher than that for winter. For the seasonal forecasting models of daily average air temperature and minimum air temperature, the fitting accuracy of the spring, summer and autumn forecasting models constructed by the four algorithms was higher, but the simulation effect of the RF model was more stable, and the coefficient of determination (R²) of the simulated values and the actual observed values were above 0.94, and the root mean square error (RMSE) and absolute error (MAE) were within 1.5 °C. For the seasonal forecast models of daily maximum temperature, the fitting accuracy of RF model for spring, summer and autumn was higher than other models in general, and its R² value was above 0.75. The MR model had higher accuracy for winter indoor air temperature and was more suitable for predicting winter greenhouse air temperature. The study concluded that it is feasible to choose the RF model to forecast the air temperature inside the glass greenhouse in spring, summer and autumn and the MR model to forecast the air temperature inside the glass greenhouse in winter, and this study can provide an important reference for the seasonal forecast of air temperature in Venlo-type glass greenhouse. [ABSTRACT FROM AUTHOR]

Thermal infrared imaging can be expected to rapidly and cost-saving monitor the soil moisture content in the largescale farmland. But it is still unclear on the impact of lighting conditions on thermal infrared images. This study aims to explore the impact of direct sunlight or shadow occlusion of the crop canopy and soil on the UAV thermal infrared remote sensing, in order to diagnose the crop water stress and monitor soil moisture content. Summer corn with different irrigation treatments was taken as the research object. The thermal infrared images were divided into four parts: illuminated canopy, shaded canopy, illuminated soil, and shaded soil. The light temperature was extracted from the higher temperature, whereas, the shadow temperature was assumed as the lower temperature. Temperature extraction was used to calculate the 11:00, 13:00, and 15:00 canopy temperature difference (difference between canopy temperature and atmospheric temperature, ΔT), crop water stress index (CWSI), and evaporative fraction (ratio of latent heat flux to effective energy, EF). A comparison was made on three changes in the monitoring effect of the index on soil moisture content after using light temperature (ΔTL, CWSIL, EFL) and shadow temperature (ΔTS, CWSIS, EFS ) at different times. The results show that: 1) There was the variation in the monitoring effects of the three indices over time. The EF monitoring effect was better at 11:00 and 15:00, the crop water stress index monitoring effect was better at 13:00. There was the less change in the ΔT monitoring over time. The temperature index should be selected for monitoring soil moisture content using field conditions and the time of flying the drone; 2) The monitoring effect was improved the most at 11:00 in the jointing period, after distinguishing light temperature and shadow temperature. The R² of EF, EFS, and EFL were 0.54, 0.65, and 0.78, respectively. The R² of CWSI, CWSIS, and CWSIL were 0.47, 0.64, and 0.70, respectively. There was no significant light temperature in the period of tasseling and filling, whereas, the index monitoring effect was significantly reduced using shadow temperature. There was the largest decrease in the CWSIS at 13:00, compared with the CWSI, where the R² decreases were 0.11 and 0.06, respectively. Therefore, it was very necessary to choose the clear and cloudless weather and avoid cloudy days, when shooting thermal infrared images. Furthermore, the impact of lighting conditions on thermal infrared images was also change with the growth period; 3) The best monitoring soil moisture content was obtained using EFL at 11:00 in the jointing and tasseling period, and CWSI at 13:00 in the filling period, where the R² of predicting soil moisture content were 0.75, 0.75, and 0.89, respectively. In addition, the soil moisture content was also dominated the monitoring effect. When the soil volumetric moisture content was around 0.23, both EFL and CWSI shared the more accurate prediction. Different time points, light temperature and shade temperature were utilized to analyze the monitoring effect of three temperature indexes on soil moisture content. The better monitoring time and index were determined in the three growth periods of summer corn. The finding can provide a strong reference for the UAV thermal infrared monitoring of soil moisture content. [ABSTRACT FROM AUTHOR]

Biomass-based porous activated carbon is a carbon-based material with well-developed pore structure, good adsorption, and capacitive properties. To achieve the goals of peak carbon dioxide emission and carbon neutrality, biomass-based porous activated carbon is widely used in the fields of electrochemical energy storage, capacitive deionization, and wastewater treatment owing to its low cost, environmental friendliness, and cleanness. Biomass-based porous activated carbon is one of the commonly used electrode materials for supercapacitors, whose electrochemical performance is mainly influenced by its physicochemical structure. To address the problems of high energy consumption and difficult regulation of the performance of porous activated carbon electrode materials, some research has proposed the activation and oxidation gradient heat treatment technology. This technology adopts a chemical-physical co-activation synergistic control process and utilizes the waste heat of pyrolysis activation, which can reduce the consumption of chemical activator and reaction energy and alleviate environmental pollution. This technology can attain the dual objectives of efficient and clean conversion of agricultural and forestry waste and high-value utilization of porous activated carbon. In this study, porous activated carbon was prepared by using waste bamboo as the carbon source and KHCO3 as the activator for medium- to high-temperature (500-800 ℃) activation and low-temperature (200-350 ℃) air oxidation using air for synergistic regulation. The study also investigated the physicochemical structure and electrochemical properties of porous activated carbon under the synergistic effect of different activation and oxidation temperatures. The results showed that porous activated carbon activated at 600 ℃ was oxidized by low-temperature air at 350 ℃ (PAC-600-350), and the specific surface area was increased from 154.361 m²·g−1 to 264.235 m²·g−1, indicating that O2 in the air activates the expansion of pores. An increase of oxidation temperature from 200 ℃ to 350 ℃ elevated the elemental oxygen content in the porous activated carbon and the content of surface oxygen-containing groups (such as -C=O-O and -C-OH), enhanced the wettability, and improved the defect structure and pore structure. Moreover, the porous activated carbon after activation at medium to low temperatures (600 ℃ and 700 ℃) is more sensitive and susceptible to oxidation by low temperature air. Among different activation temperatures from 500 to 800 ℃, the PAC-600-350 porous activated carbon had the highest oxygen content (25.54%) and degree of defects (2.53) at the activation temperature of 600 ℃; while the pore structure of PAC-800-350 is the most developed at the activation temperature of 800 ℃, with a specific surface area as high as 1096.18 m²·g−1. In addition, PAC-800-350 is less affected by the oxidation of low temperature air and its surface oxygen-containing groups change to a lesser extent. In the three-electrode test, the specific capacitance of PAC-600-350 at a current density of 1 A·g−1 was 215.29 F·g−1, which is 1.47 times that of non-air oxidized porous activated carbon. At the current density of 5 A·g−1, PAC-600-350 exhibited higher cycling stability with a capacitance retention rate of 93.51% after 5000 cycles of charging and discharging. In the two-electrode test, the symmetrical supercapacitor with PAC-600-350 as the working electrode showed good electrochemical performance, with an energy density of 9.06 Wh·kg−1 at a power density of 215 W·kg−1. Overall, PAC-600-350 porous activated carbon is considered to have potential for practical application, this study can provide a reference for high value utilization of agroforestry wastes. [ABSTRACT FROM AUTHOR]

In order to study the airflow organization in the data center and quickly predict the outlet air temperature of the rack, a rapid prediction method that combines the proper orthogonal decomposition (POD) and the surrogate model was proposed. Taking a data center as an example, the temperature field data under a large number of operating conditions were calculated via using computational fluid dynamics (CFD) software. The effects of air conditioning on the temperature field of the micro-module was analyzed. Then, the reduced order model of the cabinet outlet air temperature was established via using the POD method. The calculated temperature field data was divided into training set and test set, and the prediction accuracy of regression tree, boosted tree, support vector regression, neural network, Gaussian process regression, cubic spline interpolation, and piecewise cubic Hermite interpolation as surrogate model was compared. The consuming time of calculating the temperature field via using surrogate model and CFD software was compared. It is found that the computational speed of surrogate model composed of POD, machine learning method, and interpolation method was more than 100 times that of CFD software. [ABSTRACT FROM AUTHOR]

In order to realize the high-energy-efficiency operation of the gas pump heat pipe composite air conditioner in areas with large dry/wet bulb temperature differences, an evaporative condensation (spray/spray) device is added on the condensation side of the system, so that the system can extend the utilization time of natural cooling sources in summer high temperature seasons, reduce unit energy consumption. In the enthalpy difference laboratory, the indoor return air temperature is set to three working conditions of 24, 30, 35℃, and the outdoor temperature is adjusted every 5℃ from-10℃ to 45℃ under each indoor working condition, and record the cooling capacity, power consumption and other data of 100% load and 75% load. The results show that the evaporative condensation technology can reduce the condensing temperature, broaden the operating temperature range of the gas pump heat pipe mode, and reduce the operating energy consumption; the evaporation temperature of the system increases with the increase of the indoor return air condition. Under the indoor conditions of 24, 30, 35℃, PUE≤ 1. 33, 1.28, 1.25 were achieved respectively. Under 75% load rate, the composite air conditioner prototype can achieve PUE ≤1. 3, 1. 27, 1. 24, which has good energy-saving benefits. [ABSTRACT FROM AUTHOR]

In order to study the microclimate around of garden tree species in summer, we chose 5 garden trees including Ficus macrocarpa, Khaya senegalensis, Dracontomelon duperreanum, Lagerstroemia speciosa, Terminlia catappa as the research object in Zhanjiang, Guangdong Province. Through the observation and comparative analysis of air temperature and relative humidity, the differences in summer cooling and humidification of different garden tree species were obtained. And the discomfort index (DI) was introduced to evaluate the effects of different garden trees on human body’s comfortable degree. The results indicated that the cooling and humidification effects of different garden trees were significantly different. The order of cooling rate was Ficus macrocarpa > Dracontomelon duperreanum > Khaya senegalensis > Lagerstroemia speciosa > Terminlia catappa. The order of humidification rate was Ficus macrocarpa > Dracontomelon duperreanum ≈ Khaya senegalensis > Lagerstroemia speciosa > Terminlia catappa. The effect of reducing discomfort was also consistent with changes in cooling and humidification. Compared with lawn, trees could reduce people's discomfort in the hot summer. The research could provide certain reference and theoretical guidance for the application selection and landscape design of landscaping tree species in tropical and subtropical regions. [ABSTRACT FROM AUTHOR]

The aromatic odor of Plectranthus hadiensis var. tomentosus has been found to have the potential to improve physical and mental health of people in indoor environment, but its effectivess is reduced for that the release of volatile organic compounds from plants is susceptible to indoor environmental changes. The purpose of this study was to investigate the response of volatile organic compounds released by P. hadiensis var. tomentosus to common indoor environmental changes, and to provide a scientific basis for its efficient and sustainable application in building a comfortable pro-biotic environment to improve the physical and mental health of indoor personnel. Thus, the effects of four typical indoor environmental factors, such as air temperature, air relative humidity, CO2 concentration and light variation, on the release of volatile organic compounds from P. hadiensis var. tomentosus were investigated in this study. And the dynamic headspace and gas chromatography-mass spectrometry techniques were used to analyze the volatile organic compounds in different indoor environments with an environmental control device based on mixed-level orthogonal array design. The results were as follows:(1)Among the four typical indoor environmental factors of air temperature, air relative humidity, CO2 concentration and light condition, CO2 concentration and air temperature had greater effects on the release of volatile organic compounds from P. hadiensis var. tomentosus, while the effects of air relative humidity and light were weak.(2)For P. hadiensis var. tomentosus cultivated under normal photoperiod, an environmental condition with CO2 concentration of 500 μmol·mol-1, air temperature of 25 ℃ and air relative humidity of 60% was the most suitable for releasing volatile organic compounds from P. hadiensis var. tomentosus in the absence of light. Under this environmental condition, the total amount of volatile organic compounds released by P. hadiensis var. tomentosus was 86.23 μg·L-1·kg-1, and the content of biological active components with potentials for the positive intervention of physical and mental health was 78.03 μg·L-1·kg-1. In summary, the results suggest that when the aroma plant P. hadiensis var. tomentosus is used to build an indoor pro-biotic environment to maintain or improve the physical and mental health of people in indoor, the environmental conditions should be controlled properly, especially CO2 concentration and air temperature, so as to fully and efficiently produce the positive health benefits from P. hadiensis var. tomentosus. [ABSTRACT FROM AUTHOR]

The effect of the arrangement of thermoelectric cooler （TEC） on the natural convection characteristics of air in the cooling chamber of airborne avionics is studied by experimental research and numerical simulation. The results show that when the air is cooled, its temperature decreases while its density increases, and it begins to sink at a slow speed. Its motion form gradually transitions from deformation to rotation. It is more beneficial to the development of flow field to arrange all the TECs at the top of the chamber. However, when the air sinks to the bottom of the cooling chamber, it is easy to produce oscillation solutions, fork flow and secondary flow, and the flow enters the chaotic state. Through comparative analysis of six design cases, the best arrangement of TEC in the cooling chamber of the airborne avionics with the minimum temperature inhomogeneity coefficient and the lowest average air temperature is given. [ABSTRACT FROM AUTHOR]

This paper briefly compares the source, application scope, development history and respective characteristics of the commonly used classical models of microporous adsorption. In order to facilitate the systematic understanding and mastery of classical microporous analysis methods in physical adsorption, the methods are divided into three categories: (1) methods developed from standard isotherms, including t-method, αs-method, n-method and MP method; (2) methods based on micropore filling theory, including D-R method, D-A method and D-R-S method; (3) the currently commonly used methods include the original HK method (slit pore), HK-SF method (cylindrical pore), HK-CY method (spherical pore) and the improved HK method. [ABSTRACT FROM AUTHOR]

T-FACE (temperature-free air carbon dioxide enrichment）experimental platform was adopted. Four field treatments of winter wheat were set: field conventional temperature and CO2 concentration (CK), field conventional temperature and increase CO2 concentration to 575μmol·L−1 (C), field increase temperature (i.e., 2℃ above atmospheric temperature) and field conventional CO2 concentration (T), and field increase temperature (i.e., 2℃ above atmospheric temperature) and increase CO2 concentration to 575μmol·L−1 (CT) . Soil samples were collected at different soil layers (plough layer 0−14cm, plough bottom 14−33cm, pond layer 33−59cm and glebe layer 59−80cm) at sowing stage, overwintering stage, tillering stage and maturity stage of winter wheat, respectively, to analyze the effects of increasing atmospheric CO2 concentration and temperature on N and P content and availability in the soil. The results were as follows: (1)under the condition that CO2 concentration increased in the overwintering stage of winter wheat, the nitrate nitrogen content in pond layer of soil showed a tendency to decrease by increasing temperature. In the overwintering stage of winter wheat, except for T treatment, the nitrate nitrogen content of CK, C and CT treatment was lower than that of tilling layer during sowing stage. In the overwintering stage of winter wheat, the nitrate nitrogen content increased most obviously in CK treatment. (2) Under the condition of increasing CO2 concentration and temperature, the content of ammonium nitrogen in the soil at tillering stage and overwintering stage of winter wheat was significantly lower than that under normal CO2 concentration and temperature treatment. There was no obvious upward or downward trend in different soil layers. The content of ammonium nitrogen was relatively stable during the whole growing stage of winter wheat. However, under CT, C and T treatments, the content of ammonium nitrogen increased significantly at maturity stage of winter wheat, and the increasing trend of nitrate nitrogen was more significant under increasing temperature (P<0.05). During the whole growth stage of winter wheat, the ammonium nitrogen showed a trend of increasing first and then decreasing under C treatment, while CK, CT and T treatments showed a trend of increasing, decreasing and increasing. (3) The content of available P in CK treatment was significantly higher than other treatments in the whole growth stage of winter wheat. There was a significant difference in available P content between CK treatment and CT and T treatments at sowing stage, overwintering stage and tillering stage of winter wheat (P<0.05). The results can provide some scientific basis for rational application of N and P fertilizer, reducing unnecessary nutrient loss and preventing non-point source pollution under the condition of CO2 concentration and temperature increase caused by climate change in the future. [ABSTRACT FROM AUTHOR]

[Objective] In order to optimize the transportation of juvenile Paphia textzle Gmelin, the effects of air exposure conditions on respiration metabolism and burrowing behavior of juvenile P.textzle were analyzed. [Method] The actual transportation environment was simulated, juvenile P.textzle with body length of (3.89±0.33) mm were selected, and the oxygen consumption rate and ammonia excretion rate of juvenile P.textzle under different air exposure temperatures (10, 15 and 20 ℃) and durations (0, 3, 6, 9 and 12 hours) were examined.The data were analyzed by one-way analysis of variance and regression analysis, and the burrowing rate after re-entering water were observed, to analyze the air exposure tolerance and the differences of respiration metabolism and burrowing behavior of juvenile P.textzle. [Result] Different air exposure durations and temperatures had certain effects on oxygen consumption rate and ammonia excretion rate of juvenile P.textzle.When the air exposure temperature was the same, the oxygen consumption rate and ammonia excretion rate of juvenile P.textzle increased with the duration.When the air exposure duration was the same, the oxygen consumption rate increased with the increase of temperature, but the ammonia excretion rate decreased.Regression analysis showed that the direct effect of air exposure duration on oxygen consumption rate of juvenile P. textzle was greater than that of air exposure temperature.There was extremely significant positive correlation between air exposure duration and oxygen consumption rate (P＜0.01,the same as below),but extremely significant negative correlation between air exposure temperature and oxygen consumption rate.The direct effect of air exposure duration on ammonia excretion rate of juvenile P.textzle was greater than that of temperature.There was extremely significant positive correlation between air exposure duration and ammonia excretion rate, and also between air exposure temperature and ammonia excretion rate.At the air exposure temperature of 10 ℃,the burrowing rate of juvenile P.textzle with different durations was about 10% in 1 hours after re-entering water, which was greatly lower than that of 15 and 20 ℃ groups.With the increase of observation time, the maximum burrowing rates of 10,15 and 20 ℃ groups were 48.3%,85.0% and 88.3% respectively. [Conclusion] Compared with 10 ℃, 15 and 20 ℃ are the suitable transportation temperatures for juvenile P.textzle,and the shorter the transportation duration, the better, should be less than 9 hours. [ABSTRACT FROM AUTHOR]

Time-lag effect of vegetation refers to the growth and distribution patterns out of sync with the varying climate. Vegetation cannot adapt immediately the climate change, leading to adjustment time. Previous research has focused mainly on the overall growth of vegetation under climate monitor or changes in a single type of vegetation. It is still lacking in the timelag effect of vegetation types and their response to the climate. Therefore, this study aims to determine the vegetation activity and its response to climate change. The lag time of different vegetation types was also clarified in response to the hydrothermal changes. The Normalized Difference Vegetation Index (NDVI) and meteorological grid data were monthly collected from 1982 to 2015. The GIMMS NDVI dataset was also selected, together with the CRU precipitation and air temperature dataset. Sen + Mann-Kendall trend analysis was then conducted to obtain the interannual change rate of vegetation NDVI in over the past 34 years. At the same time, a significance test was carried out on the NDVI change trend, in order to distinguish the significant improvement and degradation areas. The growth and degradation of different vegetation types were statistically determined after the test. The lagged partial correlation analysis was used to calculate the partial correlation coefficients between vegetation NDVI and precipitation and air temperature in the current month, the previous month, the first previous two months, and the first previous three months. Then, the partial correlation coefficients were also synthesized to obtain the maximum partial correlation coefficient. The lag time was set as the maximum partial correlation coefficient. The dynamic characteristics of the vegetation pattern change over the past 34 years were presented to determine the relationship between vegetation NDVI and climate response. The lag effect was obtained in the different vegetation types on climate response. The results showed that: 1) A spatial distribution pattern of vegetation was achieved in the higher vegetation in northern Xinjiang than that in the southern, and higher in the west than that in the east. There was an overall "greening" trend in the study area. Specifically, the significantly improved and stable unchanged areas accounted for 20.6%, and 65.7%, respectively. The areas insignificant improvement and degradation accounted for 3.3%, and 10.4%, respectively. There was no area with significant degradation. In the spatial distribution, a significant NDVI increase was found in the oasis around the Tarim Basin and the northern section of the Tianshan Mountains, whereas, the Ili region showed a trend of degradation. In vegetation types, the cultivated vegetation shared the largest improvement area, accounting for 75.3%, while, the degraded area of coniferous forest was the largest, accounting for 24.2%; 2) There was a lag response of 72% of vegetation areas to the precipitation at the monthly time scale, with an average lag time of 1.1 months, while the lag response of 70% of vegetation areas to air temperature, with an average lag time of 1.4 months. The higher the lagged correlation coefficient between vegetation and climate elements was, the higher the response speed was. Overall, the vegetation was much more sensitive to the precipitation. 3) Different types of vegetation varied greatly in response to the precipitation and air temperature. Precipitation was the main promoting factor for the grassland, shrubland, and coniferous forest, while air temperature shared the strongest impact on the broad-leaved forest. The lagged partial correlation coefficients between different vegetation types and precipitation were higher than those of air temperature. The response time of different vegetation types to air temperature was longer than that of precipitation. There were lagged effects in the response of different vegetation to both precipitation and air temperature. The correlation between vegetation and precipitation was higher in Xinjiang, indicating a more rapid response of vegetation to precipitation than that to air temperature. [ABSTRACT FROM AUTHOR]

To investigate the characteristics of transpiration water consumption of Ginkgo biloba L. in the North China Plain, the Granier-type thermal dissipation probes were used to measure sap flow density in growing season of 2019 (Apr.1-Oct.31), and the environmental factors including solar radiation(Rs), air temperature(T), relative humidity(TH), soil temperature, soil humidity and wind speed were measured synchronically, aimed to study the stem sap flow of Ginkgo biloba L. in response to environmental factors. The results showed that the sap flow of Ginkgo biloba L. lasted about 194 days form April 10 to October 20. Sap flow density displayed an obvious pattern with the biggest in a sunny day, next in a cloudy day and finally in a rainy day. The diurnal changes of the sap flow density presented a typical single-peak curve under a sunny day, while it undulated widely under cloudy or rainy days due to the fluctuation of solar radiation. Transpiration water consumption in the whole growing season for the single plant of Ginkgo biloba L. was 1468.59 kg, and daily average was (6.16±3.32) kg·d–1, daily average water consumption for each month (April to October) was (2.40±1.50), (7.64±1.35), (7.78±2.03), (8.34±2.35), (8.38±3.05), (6.64 ±2.03) and (2.39±1.89) kg·d–1 respectively. Though the stand water consumption of Ginkgo biloba L. in growing season was 244.81mm, lower than the rainfall, seasonal water shortage still existed, especially in June. The partial correlation analysis showed stem sap flow density at the hour level was significantly correlated with VPD and Rs(P＜0.01), reflecting air temperature, relative humidity and energy level. While at the month level, monthly changes of daily average transpiration water consumption was significantly affected by stomatal conductance and soil temperature. There were seasonal differences on correlation degree, the highest correlation between environmental factors and sap flow appeared at the vigorous growth stage, while the lowest appeared at the early growth stage, soil humidity excluded, which had a extremely significant stress(P<0.01) on sap flow at the early growth stage. [ABSTRACT FROM AUTHOR]

Dew is one of the most important supplementary water sources in arid and semi-arid regions. The influence of dew amount on the water balance can be evaluated for water management, ecosystem protection, and the optimization of agricultural practices. Moreover, the influencing factors of dew formation can provide some insights into how climate change may impact water availability and ecosystems. However, it is still unclear in the dew formation, due to the difficulty of observation without considering the dew in the water balance. This study aims to quantify the dew amount for a better understanding of dew formation. A series of lysimeter experiments were carried out to continuously observe the dew amount in the Mu Us desert from October 2020 to September 2021. Among them, the dew amount included the fog, dew, and hoar frost formation. In addition, the meteorological factors were monitored at the experimental site, including air temperature, precipitation, wind speed, relative humidity, net radiation, and surface temperature. All data were recorded every ten minutes. The dew amount was evaluated for the water balance during formation. Boosted regression tree (BRT) model was used to investigate the influence of meteorological factors on dew formation. The results were as follows. 1) The dew amount was 47.1 mm in the experimental period, corresponding to 19.6% of the annual rainfall. The dew started to form at night when the air temperature was significantly higher than the soil surface temperature. The dew was mainly formed from October 2020 to January 2021 (cold months), with a maximum amount of 9.00 mm in December 2020, and a minimum of 0.55 mm in June 2021. The dew amount was larger in the colder months than that in the warmer ones. 2) The BRT model showed that the largest contribution (43.4%) was found in the relative humidity to the dew formation. It infers that relative humidity was a key factor in the formation of dew. The contribution rates of the net radiation at night and the wind speed to the dew formation were 21.7% and 15.2%, respectively. The much fewer contributions to the dew formation were the air temperature and vapor pressure deficit. The optimal combination of parameters was achieved in the dew formation, such as the relative humidity greater than 53%, net radiation at night less than -37 W/m², and wind speeds ranging from 0.5 to 1.8 m/s. 3) The surrounding air temperature and relative humidity of Artemisia ordosica posed the more significant influence on the dew formation, compared with bare ground. The errors of the water balance were reduced from 25.3% to 5.7%, considering the amount of dew in the semi-arid regions. The dew amount was quantified to improve the accuracy of the water balance. The finding can provide a strong reference to accurately evaluate the water resources and then better understand the formation process of dew amounts under the coverage of Artemisia ordosica. In addition, the Artemisia ordosica in the water cycle can be expected to protect the vegetation ecosystems in the arid and semi-arid regions. [ABSTRACT FROM AUTHOR]

Fragile ecological environment and shortage of water resources in Northwest China have seriously affected agricultural and economic development. Among them, the precipitation form can be one of the most important factors in the water cycle in the northwest arid region. The changes in precipitation forms can be of great significance to determining the water resources change in the background of climate warming-wetting trend in northwest China. In this study, the wet bulb temperature dynamic threshold model was established to separate the snowfall and rainfall using the daily precipitation, air temperature, relative humidity, atmospheric pressure, and station altitude data observed by the National Meteorological Station in northwest China during 1961-2017. The accuracy of the separation was also validated. A systematic analysis was made on the temporal and spatial variation characteristics of precipitation, rainfall, snowfall, and S/R in the region. Furthermore, the regional differences of precipitation in different forms and the S/R ratio were determined on the spatial scale of the secondary basin. The snowfall was divided into four types, in order to analyze the change characteristics of different types of snowfall. An investigation was implemented to explore the changes in snowfall and rainfall separation threshold and the influencing factors of precipitation forms. The results show that the precipitation in different forms in Northwest China showed a significant increasing trend during 1961-2017. However, the increasing trend of rainfall was more outstanding than that of snowfall. The Snowfall/Rainfall ratio showed a non-significant decreasing trend, with a decrease of 0.07%/10a. The spatial variation trend shared the outstanding regional differences with an “increase in the west and decrease in the east”, and the distribution of regions with the outstanding increase was concentrated in the central region of the northern Xinjiang and Hexi Corridor. The Snowfall/Rainfall ratio is distributed with “an increase in the west and decrease in the east”, and “increase in the north and decrease in the south”. The significant increase of extreme snowfall in Northwest China led to a significant increase of snowfall, with an increase of 1.07 mm/10a. Specifically, the increased rate of extreme snowfall was 1.03 mm/10 a. On the contrary, there was a more outstandingly decreasing trend in light snowfall and moderate snowfall. The slight decreasing trend of snowfall days was mainly caused by the significant reduction of light snowfall days and the significant increase of extreme snowfall days. By contrast, there was no change in moderate snowfall days and heavy snowfall days. The threshold temperature of snowfall and rainfall separation fluctuated greatly on a seasonal scale, with the highest threshold temperature in autumn, the second in winter, and the lowest in spring. The change in relative humidity caused the change in threshold temperature. Furthermore, the higher the relative humidity was, the greater the threshold temperature difference was. On the interannual scale, the threshold temperature showed a non-significant decrease trend, with a mutation change in 2008. On the watershed scale, the change rate of precipitation in each phase increased with the increase of altitude, and the Snowfall/Rainfall ratio was the opposite, the change of snowfall was mainly affected by temperature and relative humidity, and the change of Snowfall/Rainfall ratio was mainly affected by temperature in Northwest China. This finding can greatly contribute to the scientific understanding of the changing of water resources in Northwest China. It is of great significance to the rational regulation of regional hydrology and water resources. [ABSTRACT FROM AUTHOR]

Based on the daily national meteorological data in spring of 2023, relationships between meteorological factors and agricultural production in China were analyzed using statistical methods. The results showed that the national average air temperature in spring of 2023 was 11.3℃, which was 0.6℃ higher than the same period from 1991 to 2020, but with significant fluctuations. The national average precipitation was 127.2mm, which was 7.4% lower than the same period from 1991 to 2020 and the lowest since 2012. The spatial distribution of precipitation was uneven, with an overall distribution characteristic of more in the middle and less in the north and south of China. The national average sunshine duration was 634.6h, which was close to the same period from 1991 to 2020. The most summer-harvesting areas had sufficient light and heat during the yield formation stage, which was conducive for increasing the number of grains per ear and forming large ears. However, strong temperature drops and snowfall in mid-March and late-April caused varying degrees of freezing damage to winter wheat and rapeseed in Shaanxi, Shanxi, Henan and other regions. Wheat of Shaanxi and Henan experienced severe continuous rain in late-May, with the rainy period highly overlapping the wheat maturity period, resulting in moldy grains and sprouting of mature wheat. The soil moisture of spring sowing area in the northeast China was generally suitable, and the progress of spring sowing was relatively smooth. During the sowing and seedling raising period, there was no significant low temperature and low light weather in early rice regions, but there was a periodic low temperature in late-April and mid-May, which delayed the turning green and tillering process of early rice. Moderate to severe agricultural drought has occurred in southern of Sichuan and central and northern of Yunnan, affecting the sowing and emergence of maize, as well as the transplanting of one season rice and tobacco. [ABSTRACT FROM AUTHOR]

Large-scale greenhouse can be expected to serve as the future direction in the horticulture industry. However, the multi-span greenhouses can consume a large amount of energy for heating in winter in northern China, resulting in low profitability and sustainability. In this study, a multi-span greenhouse was designed with large roofs and external insulation, in order to reduce the heat loss of the greenhouse roof. The external insulation system was innovatively applied to the multi-span greenhouse. The greenhouse design was expected to improve thermal insulation performance and reduce heating energy consumption. A field test was carried out in Shouguang, Shandong Province, China. Taking the Venlo-type multi-span greenhouse in the same area as a reference, a systematic investigation was made on the light and thermal environment, thermal insulation performance of the multi-span greenhouse with external insulation. The experimental data were analyzed from continuous 40 winter days. The results show that: 1) The average solar radiation was 152 W/m² above the crop canopy inside the tested greenhouse during the day (10: 00- 16: 00), and the total light transmittance was 40%, which was 7 percentage points higher than that of Venlo type multi-span greenhouse. The best daylighting was found in the middle of the greenhouse span, due to the influence of the gutter. The solar radiation intensity at the east and west of the greenhouse span and under the gutter was reduced by 17%, 29%, and 46%, respectively, compared with the middle. 2) There was the folded in turn for the external thermal blankets covering the east and west greenhouse roofs after the sun rose. Specifically, the indoor air temperature rose at 1.9 /h from 09:30 to°C 12:00, which was 0.3 /h slower than that of the Venlo°C -type one. However, the sudden drop in the air temperature of the multi-span greenhouse with the external insulation was reduced by 0.3 within 10 min after folding insulation°C devices. The tested greenhouse was heated by the internal air circulation, with the air coming out from the ground and then returning to the equipment room through the inner side windows. During the heating period (20:00-07:00), the average temperature difference of indoor air in the horizontal direction did not exceed 1.2, without exceeding 1.0°C °C in the vertical direction. The uniform distribution was observed in the horizontal temperature of the multi-span greenhouse with the external insulation. The vertical temperature difference was smaller than that of the Venlo-type one. 3) The average air temperature at nighttime inside the multi-span greenhouse with external insulation ranged from 13.1 to 16.1, and the average temperature difference between indoor and outdoor air was 12.8°C -21.0 . The average heat°C flux of the glass roof that was covered with the external thermal blanket was 50.0-97.7 W/m², while the single-layer glass roof was 217.6-367.9 W/m² . The greenhouse covering with the external thermal blanket was reduced by 75% in the heat loss of the glass greenhouse roof. At the same time, the average heat flux was 141.1- 232.2 W/m² in the Venlo-type one with double-layer indoor thermal screens in use. The roof heat loss of the multi-span greenhouse with the external insulation was reduced by 36%, indicating a better insulation performance. The mean heat energy input of the multi-span greenhouse with external insulation was measured to be 74.5 W/m² during the heating period, maintaining an average temperature difference between indoor and outdoor air of 17.4 . Thus, the°C energy consumption of heating the multi-span greenhouse with the external insulation was low. Finally, the fitted influence of indoor and outdoor air temperature differences on the heat fluxes of greenhouse roofs was presented, and the tested greenhouse showed better goodness of fitting. This finding can provide a new type of greenhouse structure for the low-carbon and energy-saving production of multi-span greenhouses. A data basis can also be offered for the optimal design and engineering application of the multi-span greenhouse with external insulation. [ABSTRACT FROM AUTHOR]

It aims to explore the diurnal variation characteristics and influencing factors of N2O and CO2 emission fluxes in spring maize field under shallow burial drip irrigation in the Xiliaohe Plain, and to determine the best observation time in one day. During the silking stage of spring maize, the dynamic characteristics of daily emissions of N2O and CO2 under flood irrigation（CK） and shallow burial drip irrigation（DG） were studied by static obscura-gas chromatography, and their correlations with soil temperature and humidity were analyzed. The results showed that N2O and CO2 emissions had obvious diurnal variation characteristics under the two irrigation methods of shallow burial drip irrigation and flood irrigation. The diurnal variation trend was similar to that of atmospheric temperature, showing a unimodal emission curve, and the emissions both appeared about 2 hours after the atmospheric temperature reached the highest value on the observation day. The average daily emission fluxes of N2O and CO2 in flood irrigation were 199.21 μg·m-²·h-1 and 217.77 mg·m-2·h-1, respectively; the average daily emission fluxes of N2O and CO2 in shallow burial drip irrigation were 235.82 μg·m-²·h-1 and 253.54 mg·m-²·h-1,respectively, which increased by 18.38% and 16.43% respectively compared with flood irrigation. Correlation analysis showed that the diurnal changes of N2O and CO2 emission fluxes were significantly（P<0.05） or extremely significantly（P<0.01） correlated with surface temperature and 10 cm ground temperature in the treatments of shallow burial drip irrigation and flood irrigation. Soil temperature was an important factor affecting the diurnal changes of N2O and CO2emission. The analysis of the time distribution of the correction coefficient showed that the N2O and CO2 emission fluxes measured in the shallow burial drip irrigation during the time period of 08:00-10:00 am were closest to the average emission fluxes of the whole day, which was the best observation time for N2O and CO2 emissions. It is suggested that the emission flux of N2O and CO2 can be monitored from 08:00 to 10:00 in the morning after silking stage of spring maize field under shallow buried drip irrigation in Xiliaohe plain. [ABSTRACT FROM AUTHOR]

Objectives: Traditional remote sensing-based air temperature estimation method usually used the global models, which ignored the effects of spatiotemporal heterogeneity, especially for the researches in large regional areas. Methods: Taking the Yangtze River Economic Zone as a typical research area, this paper introduces the geographically and temporally neural networks for high-precision temperature estimation. The influence of spatiotemporal heterogeneity was considered by establishing the local models in the generalized regression neural network. Remote sensing data, assimilation data and station data were fused to obtain the spatially continuous near-surface temperature. The model performance was evaluated by the site-based ten-fold cross-validation method. Results: The results show that the geographically and temporally weighted neural network had effectively improved the estimation accuracy with the root mean square error(RMSE) =1.899 ℃, mean absolute error (MAE) =1.310 ℃ and correlation coefficient (R) =0.976. Compared with the multiple linear regression method and the traditional global neural network, the MAE value decreased by 1.112 ℃ and 0.378 ℃, respectively. Conclusions: The temperature mapping results indicated that the model used in this paper can well reflect the spatial distribution differences, which means that this study is possible to provide a new way for temperature estimation with high precision. [ABSTRACT FROM AUTHOR]

Ammonia (NH3 ) as an important chemical raw material has a direct influence on the development of agriculture, national economy and people's livelihood. It is a high temperature, high pressure, high energy consumption and heavy pollution process in the industrial synthesis of ammonia. Low-temperature plasma technology is a sustainable and promising technology for ammonia synthesis, which has become a research hotspot at home and abroad. In this work, nitrogen and hydrogen are used as raw materials, and nanosecond pulsed dielectric barrier discharge is used to synthesize ammonia at low temperature and atmospheric pressure. The effects of factors such as pulse peak voltage, pulse repetition frequency, total gas flow rate, and N2 ∶H2 volume ratio on the synthesis rate and energy yield of ammonia synthesis are investigated systematically through a single-factor experiment. Furthermore, through the orthogonal experimental evaluation, it is determined that the order of factors affecting the synthesis rate is: pulse peak voltage>pulse repetition frequency>gas volume ratio>gas total flow rate. The order of factors affecting the energy yield is: pulse peak voltage>gas volume ratio>pulse repetition frequency>total gas flow rate. Combined with these two parts of experiments, the optimal conditions for ammonia synthesis are finally obtained: Pulse peak voltage 16 kV, pulse repetition frequency 6 kHz, pulse rising edge 100 ns, V (N2 ) ∶V (H2 ) =1∶1, and total gas flow rate 200 mL/min. Under this condition, the highest NH3 synthesis rate is up to 923. 08 μmol/h and the energy yield is 0. 30 g/kWh, respectively. [ABSTRACT FROM AUTHOR]

In order to explore the relationship between fruit diameter and yield of red Fuji apple and environmental meteorological conditions, using the fruit diameter,single fruit weight,yield of red Fuji apple and environmental meteorological data in Wanrong from 2011 to 2020, the main environmental meteorological factors closely related to fruit diameter and yield were selected by the method of mathematical statistical analysis, and the multi-regression equation was established.The results showed that there was not obvious difference between transverse diameter and longitudinal diameter of red Fuji apple in young fruit,the growth rate of transverse diameter was greater than that of longitudinal diameter after mid June,and it initially presented partial circle or oblate circle in appearance.After late August, the growth rate of transverse diameter reached the peak, and the fruit increased the fastest.The ratio of transverse and longitudinal diameter was basically finalized by mid September.The fruit diameter was greatly affected by air temperature and precipitation, was positively correlated with the temperature in a specific period, and the precipitation in early August was significantly positively correlated with the transverse diameter.The yield was greatly affected by air temperature and sunshine, was positively correlated with precipitation in April and the relative humidity in early August. In production, increase of irrigation in April is necessary for enhancement of the fruit diameter and increase of yield. [ABSTRACT FROM AUTHOR]

Global warming has posed a great threat to agricultural production, as the worldwide climate changes dramatically. As such, the temperature can be one of the key factors to influence the growth of crops in arid and semiarid areas. In this study, the peanut was taken as the research crop in the main production areas of Xinjiang in China. The optimal sowing date of peanuts was proposed under mulched drip irrigation in the different study areas under the condition of climate change. The ground and average temperature were first collected in the same period in the experimental areas of North and South Xinjiang. The relationship was then determined between the average daily ground temperature and the average daily air temperature before sowing peanuts. The meteorological data of 51 stations was also collected from the establishment of stations in 2020. A systematic analysis was made to explore the influence of ever-increasing temperature on the sowing date of peanuts. The result showed that there was a strong linear correlation between the farmland surface soil temperature and meteorological temperature before the sowing. Further analysis showed that the farmland surface soil temperature increased with the increase of the average daily air temperature after spring, and the soil temperature in the root zone increased rapidly with the increase of air temperature after the sowing. Once the surface soil temperature was maintained at more than 12, 13, 14, and 15 for five ℃ consecutive days, the optimal daily Ordinal Numbers of sowing time were 106.94, 109.79, 112.39, and 114.39 in eastern Xinjiang, while 108.53, 111.44, 114.36, and 117.02 d in the southern Xinjiang, as well as 121.09, 124.10, 126.65, and 128.58 in the northern Xinjiang. The average root zone soil temperature was above 20 within 0 ℃ -20 days after peanut sowing with drip irrigation under mulch in the peanut production area. Furthermore, the root zone soil temperature fully met the demand for peanut seed germination, only under the condition of suitable soil moisture in the root zone. In addition, the average daily ground temperature of peanuts in the suitable sowing period increased in Xinjiang oasis after spring over 70 years. The average sowing date of peanuts was also advanced by 1.44-1.75, 1.13-1.43, and 1.05-1.88 days per decade under mulched drip irrigation in East, South and North Xinjiang, respectively. A comprehensive analysis was also performed on the change trends of the soil temperature before sowing and the soil ground temperature in the root zone after the sowing. The suitable sowing date of peanuts under mulched drip irrigation was about two days earlier in the production areas of the East than the South Xinjiang, while about 12 days earlier in the South than the North Xinjiang. The suitable sowing time was early May in the production areas of North Xinjiang. The findings can provide theoretical guidance for the selection of suitable sowing dates in different production areas of peanut in Xinjiang oasis. [ABSTRACT FROM AUTHOR]

In order to improve the pertinence of meteorological services for high-quality wheat, according to quality measurement data of 6 strong gluten and medium strong gluten wheat varieties, 287 wheat samples from 72 counties in Henan province during 2017-2019, as well as corresponding meteorological and wheat growth period observation data, analytical methods as Person correlation, LSD multi comparison and sensitive coefficient, et al., were used to confirm the key meteorological factors that influence the planting quality of strong gluten wheat in Henan province. The results indicated that, except the south of southern Henan and western Henan area, it was suitable to develop high-quality strong gluten wheat in most areas of Henan province. 6 quality indexes as hardness index, crude protein etc. were affected by the meteorological conditions after jointing to different degrees, among them, air temperature and sunshine hours at jointing-heading and mature-harvest stage had significant effect on most quality indices, air temperature and sunshine hours at flowering-grain filling stage mainly affected hardness index, sedimentation value and water absorption, and at mature-harvest stage, precipitation had negative effect on flour water absorption. Comparing the absolute value of sensitive coefficient SV(i), the sedimentation value was the most sensitive to the average maximum air temperature at jointing-heading stage, SV(i) reached to 0.7954. For different developmental stages, the key meteorological factors for planting quality reaching the standard of strong gluten wheat were as follows: average maximum air temperature, air relative humidity and sunshine hours at jointing-heading stage, air relative humidity at flowering-grain filling stage, and average air temperature at mature-harvest stage. The results explained that the most important meteorological factors effecting the planting quality of strong gluten wheat was air temperature. [ABSTRACT FROM AUTHOR]

Reference crop evapotranspiration (ET0) is one of the most important hydroclimatic variables for the hydrologic and crop models, as well as the actual evapotranspiration in the irrigation schedule. The ET0 prediction a few months in advance can be beneficial to the decision-making on the long-term planning in the water management and irrigation communities. In this research, the monthly predictions of ET0 were realized over the Huaihe River basin using the model data of Beijing Climate Center second-Generation Climate Prediction System (BCC_CPSv2), and the surface meteorological observations at 172 stations during 1991 to 2020. The bilinear interpolation and quantile mapping were also selected to downscale and then correct the mean air temperature, net radiation, relative humidity, and wind speed of BCC_CPSv2. The obtained four variables were used to calculate the ET0 predictions using the Penman-Monteith equation. The correlation coefficient (r), Mean Bias Error (MBE), Root Mean Square Error (RMSE), and Mean Absolute Percentage Error (MAPE) were employed to evaluate the ET0 prediction performances of the model, and the four climatic variables before and after correction. Results showed that the mean air temperature, net radiation, and relative humidity from the model were significantly smaller than those from the observations before correction in each month with the RMSE of 1.84℃, 1.70 MJ/(m2 ·d), and 15.79%, respectively. The wind speed was also smaller during March to June, but larger in other months, with the RMSE of 1.39 m/s. Errors in the climatic variables led to the lower ET0 during February to June, and the larger ET0 in January, as well as in July to December, compared with the calculations. The RMSE of ET0 before correction was ranged from 0.11 to 1.70 mm/d for each month, among which was the highest in summer. The larger RMSE exceeding 0.50 mm/d occurred in eastern coastal areas in January and October, while the southwestern mountainous areas presented the higher RMSE exceeding 0.70 mm/d in April and July. The model skills on predicting climatic variables and ET0 were improved effectively by the quantile mapping. The RMSE of air temperature, net radiation, relative humidity, and wind speed decreased to 1.32℃, 0.74 MJ/(m2 ·d), 7.38%, and 0.53 m/s, respectively. Especially, the MAPE of wind speed and net radiation was decreased by more than 19%. The RMSE of ET0 after correction was ranged between 0.05 and 1.22 mm/d for each month, indicating the decrease in 80% of the months. The performances of the model were improved significantly for the eastern coastal areas in January, and the southwest mountainous areas in April, July and October, where the RMSE decreased by more than 0.30 mm/d. Before and after the correction, the net radiation and relative humidity were the primary factors for the ET0 prediction errors in summer half year and winter half year, respectively, due to the larger errors of the model and the higher sensitivity of ET0 to them. A better performance was achieved in the monthly ET0 prediction after the model correction with the error about 10.7%. The finding can provide a strong reference for the water resources management, irrigation schedule planning, and agricultural water demand decision-making. [ABSTRACT FROM AUTHOR]

【Objective】The present research was to explore the effects of low temperature stress（0 ℃） on physiological, biochemical indexes and photosynthetic characteristics of three ferns. 【Method】Asplenium nidus, Nephrolepis exaltata cv. Bostoniensis and Davallia trichomanoides were used as experimental materials. After low temperature stress（0 ℃）for 48 hours, 96 hours and 48 hours recovered at air temperature（20 ℃）, the physiological, biochemical and photosynthetic indexes were measured. 【Result】With the increase of the exposure to low temperature, the relative electrical conductivity（REC）, the contents of soluble protein and sugar superoxide diamutase（SOD） and peroxidase（POD） activities increased in three fern species in general. These indexes were decreased at 48 hours under 0 ℃ and increased when the ferns were subjected to air temperature（20 ℃）. The chlorophyll and malondialdehyde contents had different trends. With the increase of the treatment time（0 ℃）, the net photosynthetic rate（Pn）, transpiration rate（Tr）, stomatal conductance（Gs） and water use efficiency（WUE） decreased, and the intercellular CO2 concentration（Ci） increased in three fern species. The Pn, Tr, Gs and WUE in the three fern species rose again in some extent, whereas their Ci decreased in some extent after cessation of the low temperature treatment, which was important regulatory mechanism for the acclimation of these three fern species to low temperature stress. Principal component analysis showed that the largest eigenvector in principal component 1 was Pn, followed by Tr and WUE, the largest eigenvector in principal component 2 was chlorophyll, followed by soluble protein and soluble sugar.【Conclusion】The responses of the three ferns to low temperature stress were different. Using the membership function method for comprehensive evaluation, the tolerance of three fern species under low temperature stress was in the order of A. nidus>D. trichomanoides>N. exaltata cv. Bostoniensis. [ABSTRACT FROM AUTHOR]

When the daily average water temperature exceeds 32℃, the hatching rate and feeding rate of some warm water fish decrease with the increase of temperature, grow slowly or stop growing, and are easy to induce diseases. In summer, the water temperature in the fish pond is not always in the high temperature period. In this paper, based on the water and air temperature data of Fushun Aquaculture Meteorological Service Test Base from 2017 to 2019, the variation characteristics of water temperature in each layer of fish pond in summer were analyzed, and the prediction models of average and maximum water temperature on the sunny days were established by stepwise regression analysis. Results showed that the daily max. water temperature in each layer in summer occurs from 18:00 to 19:00, which lagged behind the temperature by 1-3 hours. The period when the water temperature ≥32℃ was mainly concentrated from 16:00 to 22:00, and the hourly average water temperature of each layer in this period was 32.9-33.1℃, 32.6-32.7℃ and 32.1-32.3℃, respectively. The water temperature of each layer fluctuated and rose with the temperature in summer, especially from mid-June to early-July, while the maximum values of temperature and water temperature appeared in late-July. The average number of days with water temperature ≥32℃ in summer was 23 days, accounting for a quarter of the whole summer, mainly from late July to mid-August. During this period, the daily average water temperature of each layer was 28.5-34.4℃, 28.2-34.1℃ and 27.9-33.9℃, respectively. The back substitution test in 2017-2018 and the forecast test in 2019 showed that the average absolute error of the model was 0.3-0.8℃, and the average relative error was within 2.6%, indicating that the model has good prediction effect and can be better applied to the prediction of fish pond water temperature in summer. [ABSTRACT FROM AUTHOR]

Based on COMSOL Multiphysics, the effects of temperature and humidity on atmospheric corrosion behavior of 6063 aluminum alloy and cathodic protection of sacrificial magnesium anode were simulated. The results showed that temperature had a slight influence on atmospheric corrosion of 6063 aluminum alloy within 0~120℃, and there was a positive correlation between temperature and corrosion degree. The corrosion situation was the most serious at 120℃, and the annual corrosion thickness was around 1.48μm/a. When the relative humidity in the range of 0.35~0.85, the corrosion rate was first stable, then decreased, and then increased. The corrosion was the least severe at 0.6 relative humidity and the most severe at 0.85 relative humidity. The annual corrosion thickness was 38.684μm/a, and the corrosion products will slow down the occurrence of corrosion with the increase of time. Protective studies used magnesium as sacrificial anode showed that the change of relative humidity had a little effect on the corrosion of sacrificial anode protection, the potential of the whole motor shell was within the protection voltage range, which indicated that the cathode protection method of sacrificial anode used in the aluminum alloy shell of electric vehicle motor had a good protection effect. [ABSTRACT FROM AUTHOR]

Dew formation and its influence on soil water content are an important basis for next-level quantification of water cycling and eco-hydrological processes. To reveal the dew formation process, over a consecutive 3-year period, we monitored meteorological parameters and soil water content in the top layer at 30-minute recording intervals in the Central Ningxia Province arid belt. The dew amount was measured using a leaf wetness sensor. Annual dew yield in this region reached 56.41 mm, 75% of which occurred from June to October. Maximum monthly and maximum daily dew were 13.40 mm and 0.80 mm, respectively, and mainly occurred in the early morning from 03:00 to 08:00 am. Meteorological parameters responsible for dew formation were: air temperature between 0—24.4 ℃, relative humidity between 50%—100%, wind speed between 0.16—1.74 m/s, and wind direction between 30—60 degrees and 270—330 degrees. There was a very significant and highly correlated linear and inverse relationship between relative humidity and the difference between air temperature and dewpoint. When the difference was < 3 ℃ and the corresponding humidity > 80%, dew formation was much more likely. When daily dew reached 0.6 mm, 0.7 mm and 0.8 mm, soil water storage in the top 5cm soil increased by 0.10 mm, 0.20 mm and 0.25 mm, respectively. Annual dewfall was 13.5% of the rainfall, and the annual frequency of dew occurrence was 126 days (35%), indicating that dew is a significant water source for local water and ecosystem cycling. [ABSTRACT FROM AUTHOR]

Cooling-dehumidification technology is gradually applied to the semi-closed structure of the greenhouse. The reason can be that the indoor air humidity is usually higher than the suitable growth range of the planted crops. Among them, the airside performance of the fin-tube heat exchangers directly dominates the efficiency of the cooling-dehumidification system. In this study, a systematic investigation was made to clarify the influence mechanism of the greenhouse environment on the airside performance of the aluminum fin-tube heat exchangers with the hydrophilic coating (thickness 0.8 μm). An airside performance experiment was then conducted on the greenhouse environment created by a wind tunnel, in which the air temperature was 285 to 308 K and the relative humidity was 60% to 90%. The experimental platform of the wind tunnel consisted of the airflow rate measurement, the air temperature and humidity treatment, the fin-tube heat exchanger test, and the refrigerant circulation circuit, according to the American Society of Heating Refrigerating and Air conditioning Engineer (ASHRAE) standards. A comparison was made on the airside performance of the exchanger with and without hydrophilic coating. The correlation analysis was carried out between the predicted and experimental data, in terms of the heat transfer, mass transfer, and friction factor for those without hydrophilic fins. It was found that the predicted values deviated significantly from the experimental data. By contrast, multiple nonlinear regression was utilized to add the correction factors of temperature and relative humidity into the correlations of the fin-tube heat exchanger without hydrophilic coating. The new correlation was then applied to the fin-tube heat exchangers with the hydrophilic coating in the greenhouse environment. The results showed that the hydrophilic coating dominated the airside performance of the fin-tube heat exchanger in the greenhouse environment. The heat transfer factor, mass transfer factor, and friction factor of the fins with the hydrophilic coating were smaller than that of those without hydrophilic coating, in which the hydrophilic coating posed the most significant effect on the friction factor. The maximum difference in the friction factor of fin-tube heat exchangers with and without hydrophilic coating was 53.9%, indicating that the fins with the hydrophilic coating effectively promoted the discharge of condensate. The heat transfer factor, mass transfer factor, and friction factors of the fins with the hydrophilic coating decreased with the increase of airside Reynolds number and refrigerant inlet temperature, but increased with the rise of relative humidity. The mass transfer factor was more sensitive to the inlet relative humidity. Once the inlet temperature of refrigerant was 285 K, the inlet air relative humidity was 80%, and the air inlet temperature increased to 300 K, indicating the maximum heat transfer factor. There was no influence of the air inlet temperature on the heat transfer performance of the airside in this case. The predicted values of the selected correlation of the smallest deviation were larger than the experimental data. The maximum deviation reached 52.5%, 219.6%, and 71.1% for the heat transfer factor, mass transfer factor, and friction factor, respectively. The new correlations for the corrected heat transfer factor, mass transfer factor, and friction factor were 92.9%, 96.4%, and 96.4% of the experimental data within ±10%, after the correction factors were introduced for the temperature and relative humidity into the selected correlations. The mean deviation of the heat transfer factor, mass transfer factor, and friction factor were 5.1%, 5.9%, and 4.7%, respectively. The finding can provide a strong reference for the thermal design and application of fin-tube heat exchangers with the hydrophilic coating in the cooling-dehumidification systems of the greenhouse. [ABSTRACT FROM AUTHOR]

[Objectives]In order to improve the work performance of a heat pump system at low temperature and meet the heat demand of drying operation under different working conditions, one new type of heat pump system with the variable frequency compressor for grain dryer was designed and developed. [Methods]This heat pump system was composed of one variable frequency compressor and four constant frequency compressors. Its performance at low temperature significantly improved and the theoretical output heat could vary in a wider range, which could meet the need for heat cost of the drying operation under different working conditions. We had conducted some production tests, in order to test the relative performance of the variable frequency heat pump system. [Results]The tests results showed that after a variable frequency compressor was adopted, the outlet hot air temperature of the system increased by about 32% compared to the normal frequency system at the ambient temperature of 0-5 ℃, which met the commend of paddy drying under a low temperature condition. The production test of rice drying was carried out by using the developed variable frequency heat pump system. The results showed that its average coefficient of performance(COP)was 3.67 and average dehumidification energy consumption ratio was 2.08 kg·(kW·h)-1. Compared with the constant frequency heat pump system, there were increases of 16.5% and 34.4%, respectively. [Conclusions]Compared with the normal frequency system, the heat pump system of grain dryer with variable frequency compressor not only can significantly improve the air outlet temperature of the system at low temperature, but also has better performance. [ABSTRACT FROM AUTHOR]

In the summer of 2022 (June-August), the national average air temperature was 22.3°C, which was 1.1°C higher than the same period of the normal year (1991-2020). There were sufficient thermal resources in major agricultural areas. The national average high temperature days reached 14.3d, which was 6.3d more than that in the same period of from 1991 to 2020, and had been the maximum value since 1961. The national average precipitation was only 290.6mm, being the second smallest in the same period since 1961. The national average sunshine duration was 677.4h, which was close to the same period in the normal year and 53.7h more than that in 2021. The weather in most summer-harvesting areas was fine, which was conducive to the full maturity and quality improvement in grain and oil crops. There were two obvious precipitation events in late June, which effectively alleviated the previous drought in the northern summer-sowing areas. However, the deviation of soil moisture was not conducive to timely summer planting in some areas in Shaanxi and Gansu. Most of the agricultural areas were exposed to sufficient light and heat, with no occurrence of obvious cloudy and rainy weather. There was abundant precipitation and suitable soil moisture in the northern agricultural areas, which was in favor of the growth, development and yield formation for local crops such as corn and soybeans. The continuous high temperature and lack of rain in the southern agricultural areas led to the development of agricultural drought and heat stress for crops such as rice and maize. The meteorological conditions limited the stable growth of crops, economic trees and fruits. Superimposed precipitation occurred in Liaoning and Shandong, resulting in waterlogging in some lowland areas. Moreover, periodical low temperature in early June and late August affected the growth, development and grain filling of -harvesting crops in the Northeast. [ABSTRACT FROM AUTHOR]

【Objective】The present paper aimed to explore effects of different shading models on tea garden habitat and the quality of summer tea, to find out the suitable shading models for tea trees, so as to provide theoretical basis for the production of high-quality summer tea in Guangxi. 【Method】In summer of 2020, Jinxuan was used as the test variety, and black shading net was used as the shading material and 4 shading treatments T1（60% shading+1. 3 m shed covering）, T2（60% shading+1. 8 m shed covering）, T3（75% shading+1. 3 m shed covering） and T4（75% shading+1. 8 m shed covering） were set, with no shading as the control（CK）. Cultivation experiments of different shading models were carried out in tea garden, and the tea garden habitat index（illumination intensity, air temperature, air relative humidity and soil temperature） and the quality ingredients index of tea（chlorophyll, tea polyphenol, amino acid, vitamin C, water extractive, caffeine） were analyzed. 【Result】Different shading models could effectively reduce the illumination intensity, air temperature and soil temperature, increase the air relative humidity, improve the habitat of tea garden and improve the quality of summer tea. Effect of treatments T3 and T4 on improving tea garden habitat were better than those of treatments T1 and T2. After 25 days of shed covering, the total chlorophyll contents of summer tea were T3>T4>T2>T1, which significantly increased by 79. 66%, 56. 13%, 28. 24% and 17. 31%（P<0. 05, the same as below） compared with CK, respectively. The tea polyphenols contents were T4T3>T2>T1, which significantly increased by 14. 67%, 10. 67%, 5. 78% and 4. 00% compared with CK, respectively. The proportion of essential amino acids in amino acid components were T4>T2>T1>T3, which were 2. 85%, 2. 75%, 1. 77% and 1. 59% higher than that of CK, respectively. The ratio of tea polyphenol to amino acid were T4T4>T1>T3, which significantly increased by 13. 74%, 12. 73%, 10. 01% and 8. 31% compared with CK, respectively. The water extract contents were T4>T2>T3>T1. In comparison with CK, the water extract contents of T4 and T2 treatments significantly increased by 65. 53% and 16. 00%, T3 treatment decreased by 3. 92% but did not reach significant difference（P>0. 05, the same below）, while T1 treatment decreased significantly by 5. 28%. And there were no significant differences in caffeine contents between shading treatments and CK. 【Conclusion】The model of 75% shading+1. 8 m shed covering can significantly improve the habitat of tea garden and improve the integrating quality of summer tea. This model is recommended as a supporting technology for the high quality summer tea production to be extended in Guangxi. [ABSTRACT FROM AUTHOR]

In this study, the influence of the process parameter setting of the hot-air leaf moisturizer on the quality index of the exit leaf during the secondary leaf conditioning of threshing and redrying is studied, and the corresponding prediction model is established. A BP neural network prediction model is established based on the characteristics of the secondary leaf conditioning process data. The current popular neural network writing framework TensorFlow’s high-level API interface is called to construct the neural network structure. The activation function, optimizer, number of hidden layer neurons and other key parameters are gradually adjusted in the neural network structure to make the prediction result of the test set reach the best state. By inputting the parameters of the front steam nozzle pressure, front-end water flow rate, hot air temperature, return air temperature, feed blade temperature, and feed blade moisture combination, the two key tobacco leaf evaluation indicators, namely, outlet leaf moisture and temperature, are predicted. According to the mean square error, root mean square error, and average absolute error of the prediction results, it is concluded that when the number of neurons in the hidden layer is 7, the activation function selects ReLU, and the optimizer selects RMSprop, the effect is the best. [ABSTRACT FROM AUTHOR]

Based on the daily national meteorological data in spring in 2022, relationships between meteorological factors and agricultural production in China were analyzed using statistical methods. The results showed that the national average air temperature in spring in 2022 was 12.1Ž, which was the highest during the same period since 1961. The national average air temperature in the first ten days and the second ten days in March, and also in the first ten days in April, was abnormally higher than the same period from 1991 to 2020. The national average air temperature in the second ten days in May was obviously lower than the same period in the normal year. The year 2022 was a typical cold year in late spring. The national average precipitation in spring in 2022 was 154.0 mm, which was more than that in the same period in the normal year. In particular, the average precipitation in Sichuan in spring this year was the most since 1961. The national average sunshine was 649.2 hours, close to the same period in the normal year. The suitable sunshine and temperature, and also good soil moisture conditions were favorable for winter wheat growth with delayed sowing date in autumn in 2021 in Northern China, and the delayed-sowing winter wheat growing conditions continued to improve and upgrade in spring in 2022. The meteorological conditions in spring in 2022 were generally conducive to winter wheat growth and yield increase per hectare. The soil moisture and temperature conditions were suitable in most of the spring sowing areas, and the influence of phased low temperature was relatively light, which was conducive to the sowing and emergence of crops in spring. The progress of spring sowing was generally faster than that of the previous year. The seedlings growed well. It was sunny during most of winter wheat mature and harvest period in southern China, and the wheat harvest progressed well. But obvious drought in western Liaoning was unfavorable to spring sowing. In the late spring, heavy rainfall occurred in the east of Jianghan, the south of Jianghuai, the west of South China and the Southwest China. There were many rainy days and little sunshine in the south of Southwest China. At the end of spring, hot and dry weather appeared in some wheat areas in Eastern North China, Huang Huai. The bad weather had a certain negative impact on spring sowing and late grain filling of winter wheat in some of the above regions. [ABSTRACT FROM AUTHOR]

Water conservancy engineering has been one of the most important human activities to impact the hydrological process in the watershed. Among them, the agricultural reservoirs for irrigation can change the various hydrological elements in the watershed, even the water resources utilization and agricultural production. The Manla Reservoir (known as “The first dam in Tibet”) has also posed a great challenge to water resources management and agricultural development in the Qinghai-Tibet Plateau. Taking the Nianchu River near the Manla Reservoir as an example, this study aims to determine the optimal parameters using the Soil and Water Assessment Tool (SWAT). The runoff was predicted after the construction of the reservoir using the data before construction. The Modified Normalized Difference Water Index (MNDWI) was combined with the inflow, outflow, and water storage of the reservoir after the SWAT simulation. A Vegetation Interface Processes (VIP) model was used to calculate the cultivated land Gross Primary Productivity (GPP) in the reservoir dispatch scenario using the farmland water balance. The ridge regression was selected to quantify the effects of human activities on the GPP, such as the reservoir irrigation and major climatic factors (Carbon dioxide concentration, Air temperature, Precipitation, and Solar radiation). The results show that: 1) The runoff decreased 3.78×109 m3 after the construction of the Manla Reservoir, according to the simulation of the SWAT model. Among them, 2.5×109 m3 of water was transported through the Manla reservoir for irrigation per year. The utilization rate of runoff increased from 10.3% to 25.1% in agriculture in the basin. Due to the impoundment of the reservoir, the runoff of the Manla Reservoir was reduced by 0.65×109 m3/a. 2) The average annual GPP of cultivated land was between 143 and 853 gC/(m²·a) in the VIP model. The average annual GPP of cultivated land increased by 5.3 gC/(m²·a2). The GPP of more than 90% of the cultivated land areas showed an upward trend during the operation of the reservoir (2000-2019), of which more than 67% was a significant upward trend. There was a changing trend in the spatiotemporal scale for the carbon dioxide concentration, air temperature, and radiation during the operation of the reservoir, indicating an excellent agreement with the GPP. But, there was negatively correlated between the precipitation and GPP. 3) The operation of the Manla Reservoir greatly contributed to the deployment of water resources. The GPP increase was attributed to the irrigation and CO2 concentration, according to the ridge regression model. The average relative contributions were 43.9% and 25.1%, respectively, which were much higher than those of all climatic factors. The relative contributions of air temperature, radiation, and precipitation were only 14.7%, 6.9%, and -5.1%, respectively. Consequently, there was some impact of the construction and operation of the Manla Reservoir on the eco-hydrological elements (runoff, and evaporation) in the basin. The relative contributions of Manla reservoirs were quantitatively analyzed to improve the irrigation level and crop production. The finding can provide a strong reference for the decision-making on water resources allocation and agricultural irrigation instruction. [ABSTRACT FROM AUTHOR]

There exists the problem of high energy consumption in operation of air conditioning equipment in data center. To maintain efficient and energy-saving operation of air conditioning equipment in data center, the optimal operating air volume ratio of indirect evaporative cooling equipment in data center was found through simulation test of prototype in enthalpy difference laboratory. The optimal secondary/primary air volume ratio was studied, and it is found that when operating under the same outdoor operating conditions, the optimal air volume ratio of wet mode is smaller than that of dry mode. When the secondary air flow remains unchanged, the wet mode makes the primary air reach a lower temperature; that is, if a certain temperature point is to be reached, the secondary air volume required in wet conditions is smaller; when the unit is operating in a dry area, the optimal air volume ratios of dry mode and wet mode are 2. 1 and 1. 9, respectively, and the corresponding evaporative cooling efficiencies are 69. 78% and 73. 5%, respectively. Under the optimal air volume ratio, the corresponding temperature drops can reach 19. 16 °C and 18. 15 °C, respectively. Under the working conditions in the humid area, the opti-mal air volume ratio of the wet mode is 2, and the corresponding evaporation efficiency and sup-ply air temperature are 56. 76% and 22. 67 °C, respectively. [ABSTRACT FROM AUTHOR]

In order to provide reference for vegetable growth management and environmental optimization regulation, the dynamic changes of greenhouse temperature and humidity were predicted by using ARIMA model and RBF neural network. In this study, the data from July 28 to 29 were taken as the validation set, and the data from the previous 5 to 25 days were taken as the sample set. Three input variables were set to explore the temperature and humidity model prediction effects. Based on the measured data of air temperature, relative humidity and light intensity in the vegetable greenhouse, and according to the difference in the predictive ability of ARIMA model and RBF neural network for linear and nonlinear problems, temperature and humidity prediction models based on weight combination of ARIMA and RBF neural network were constructed. The results showed that the temperature and humidity in the greenhouse had more obvious linear and nonlinear variation characteristics, respectively, and the single models with better prediction effects were the ARIMA model and the RBF model. The optimal single temperature model was the model ARIMA(0,1,1)(1,1,1) 24 with 25 days sample set. The optimal single humidity model was the RBF model (3-6-2) with 25 days sample set and input variable A (temperature, humidity and light intensity). Compared with the optimal single models, the ARIMA-RBF neural network weight combination model had higher prediction accuracy and better stability. The MAE, MAPE and RMSE were 1.04°C, 2.95%, 1.21°C for the optimal temperature combination model and 0.35 percentage point, 0.36%, 0.55 percentage point for the optimal humidity combination model. The weight combination model gives full play to the ability of single models to process data from different characteristics through an appropriate weighting strategy, and can better evaluate the temperature and humidity status in the greenhouse, which provides a reference for establishing a more universal greenhouse environmental factor model. [ABSTRACT FROM AUTHOR]

Drought has become a global concern, and timely and accurate drought monitoring has an important guiding significance for the regional ecological security, economic development, and agricultural production of countries along the "New Silk Road Economic Belt" in the context of global warming. Since natural disasters have occurred frequently around the world in recent years, the drought has also posed a great threat to the global ecological environment, particularly to the long-term social and economic development of Central Asia and the surrounding countries. In this study, a Temperature Vegetation Dryness Index (TVDI) model was established using the MODIS Land Surface Temperature (LST) and Normalized Difference Vegetation Index (NDVI) in Central Asia from 2001 to 2020. Based on trend analysis, MK test, and geographic detectors, the spatial and temporal variations, of drought and drought changing patterns in Central Asia in the last 20 years, the drought evolution pattern and the influence of different factors (temperature, mean annual precipitation, land use type, population density, DEM, slope, aspect) on TVDI were also investigated. The results show that: 1) There was an obvious regional pattern in the spatial distribution of TVDI in the study area, which were mainly characterized by regional and local droughts. The frequency and degree of droughts in the southwestern part of Central Asia are than those in the northeastern part, with a decreasing trend from the southwest to the northeast. For all the study area, 66% of the area showed a significantly increasing trend of drought (P<0.05), whereas, 34% of the area showed a significant decreasing trend of drought (P<0.05), indicating a pattern of "dry in the north and wet in the south". Overall, Central Asia shows an increasing trend of aridity, with the most severest drought in the northwestern part of Kazakhstan. 2) The degree annual of drought slightly increased over the past 20 years, with the severest drought occurred in 2012. There was a significantly different spatial distribution of TVDI, which with a clear seasonal change. The drought degree was ranked as follows: summer>spring>autumn. 3) The single-factor detection results showed that the contribution of the influencing factors to drought was ranked as follows: temperature > DEM > slope > precipitation > land use type, with the controlling factors of temperature and DEM for the drought (all q values were greater than 0.45). The multi-factor analysis showed the two-factor enhancement and non-linear enhancement, with t major contribution from the four combinations, e.g., — temperature and DEM, temperature and slope, temperature and land use, and temperature and precipitation. Under the background of global climate warming and increasing human activities (vegetation deterioration, urbanization and construction, cultivation, overgrazing, industrial pollution, etc.), the air temperature gradually increased and the precipitation decreased in Central Asia over the past 20 years. These changes led to vegetation degradation, which in turn resulted in ecological degradation and increased drought degrees. This finding can provide a scientific reference for the decision-making on the drought prevention and control, particularly for the ecological risks and geo-security impacts. [ABSTRACT FROM AUTHOR]

The composite organosilica membrane(BTESE-BPh)is developed by the copolymerization reaction between 1,2-bis(triethoxysilyl)ethane(BTESE)and 4,4'-bis(triethoxysilyl)biphenyl(BTESBPh).Compared with the classical BTESE membrane, the BTESE-BPh membrane has a larger pore size, which greatly improves its ability to capture CO2. N2 adsorption-desorption isotherms and gas permeation tests confirms the structural evolution of the composite membrane. For the separation application of CO2/N2, the CO2 permeance reaches 2.49×10-6 mol·m-2·s-1·Pa-1, and the CO2/N2 selectivity approaches 22.2, exhibiting great advantages in CO2 capture applications. [ABSTRACT FROM AUTHOR]

Herein, the slope- scale dynamic changes in water cycle processes such as infiltration, evapotranspiration, thermal-moisture conditions in the active layer, and suprapermafrost groundwater in response to changes in the underlying surface conditions are analyzed based on the complete hydrometeorological observation network in the small Fenghuoshan watershed (FHS)- a typical permafrost basin- in the source region of the Yangtze River. The following four key results were obtained: ① The multi- year average of actual evapotranspiration (ET ) of the FHS during the growing season was 472. 1 ± 42. 9 mm, and the order of meteorological factors affecting the ET was as follows: net radiation (sensitivity coefficient SRn = 1. 22, correlation coefficient R = 0. 93) > air temperature ( STa = 0. 33, R = 0. 84) > relative humidity (SHR = 0. 32, R = 0. 46) > wind speed (SU = - 0. 25, R = - 0. 27). The ET was positively correlated with vegetation cover and altitude on the slope scale. ② The initial and stable infiltration rates increased with altitude on the slope scale. During the initial thawing, completely thawed, and initial freezing periods, the respective stable infiltration rates at various slope positions were as follows: top of slope (1. 07 mm / min, 0. 63 mm / min, 0. 88 mm / min) > middle of slope (0. 29 mm / min, 0. 45 mm / min, 0. 21 mm / min) > base of slope (0. 11 mm / min, 0. 30 mm / min, 0. 10 mm / min), while the influence of vegetation coverage on the infiltration rate varied with the freezing-thawing period. ③ The differences in the freezing and thawing initiation times on the sunny and shady slopes, and at different slope positions, were reflected in the changes in soil moisture and groundwater level, thus explaining the spatial-temporal differences in the runoff- generation areas of the permafrost basin in going from the sunny slope to the shady slope, and from low altitude to high altitude. ④ The freezing-thawing regime of the active layer below 50 cm depth was found to significantly affect the groundwater dynamics, and the influence of topography, vegetation, and soil texture differences on heat transfer jointly led to the spatial variations in the suprapermafrost groundwater dynamics on the slope scale. [ABSTRACT FROM AUTHOR]

The threonine gene-engineered strains with the resistance to pha-ges were screened by atmospheric room temperature plasma (ARTP). The mixed phage (P-1) was isolated from the broth of threonine fermentation. P-1 was used as screening factor to mutate threonine producing strain YPT by atmospheric plasma at room temperature, preliminary screening of resistance, lysogenicity verification, genetic stability verification of phage resistance and acid production verification in fermentation tank. The results showed that a threonine producing strain with stable resistance to P-1 was obtained, which named YPT-1. The mechanism of the strain YPT-1 against phage was investigated based on molecular level. The knockout of fhuA gene was carried out by CRISPR, which indicated that the deletion of fhuA could lead to the achievement of phages resistance. The study indicates that compared with the control strain (YPT), the acid production index of the strain doesn't decrease. and the acid production is stable, which has good industrial application value. [ABSTRACT FROM AUTHOR]

[Objective] The purpose of this study is to understand the thermal stability and thermal behavior of 10 colorants. [Method] The thermogravimetric process of 10 kinds of colorants with temperature change in the air atmosphere was studied using the thermogravimetric analysis technique. [Result] There were obvious differences in the thermogravimetric processes of different samples. The TG curves of allura red and amaranth were divided into two weightlessness stages, and the main weightlessness stages occurred at 35S. 02 - 520. 36 and 361. 60 - 548. S9 "C, respectively. The TG curves of azorubine and carmine were divided into three weightlessness stages, and the main weightlessness stages occurred at 438 . 36 - S86. 40 and 711. 97 - 790. 33 "C, respectively. The TG curves of quinoline yellow, carmosine, erythrosine, indigo, brilliant blue, lemon yellow, and sunset yellow could be divided into four weightlessloss stages, and the main weight lessloss stages occurred at 722. 8S - 798. 00, 341. 14 - 4S2. 21, 460. 47 - SSS. 64, S61. 87 - 797. 86, 38S. 10 - 672. 72 and 4S3 . S7 - 637. S4 "C, respectively. Sunset yellow, carmosine, and lemon yellow showed the greatest weight loss at the third stage, ranging from 27. 74% to43. 74% . Brilliant yellow and quinoline yellow showed the greatest weight loss at the fourth stage, 30. 98% - 41. 28% . And the maximum weight lessloss of the remaining colorants occurred in the second stage, 33. 13 % - S8. 07 % . At the end of pyrolysis, the residual amount of allura red, amaranth, carmosine, carmine, and quinoline yellow was between 17. S2 % and 28. 77 %, and erythrin residue ramaing amount was 1. 33 % . [Conclusion] The 10 synthetic colorants showed different weightless loss stages, which could be divided into 2, 3 and 4 stages. Also, the main weightless loss stages were inconsistent, and there were differences in the heat changes in the DSC curves. All 10 synthetic colorants might burn in the final stage. The results of the thermogravimetric analysis technique showed that 10 kinds of water-soluble synthetic organic colorants did not decompose under 200 'C in air atmosphere, which indicated that 10 kinds of water-soluble synthetic organic coloants had good thermal stability. From the effect of heat on the stability of synthetic colorants, indigo was the most stable, followed by quinoline yellow. Thermal stability was ordered by indigo > quinoline yellow > amaranth > allure red > erythrosine > sunset yellow > carmine > carmosine > brilliant blue > lemon yellow. There was no significant difference in the thermal stability between azo pigments (amaranth, allure red, sunset yellow, carmine, carmosine, and lemon yellow) and non-zo pigments (indigo, quinoline yellow, erythrosine and brilliant blue). [ABSTRACT FROM AUTHOR]

To investigate the effects of high temperature and high humidity compound disasters on leaf photosynthesis and flower sex differentiation of cucumber plants, the cucumber variety "Jinyou101" was used as the test materials. The three factors orthogonal test of air temperature, air relative humidity and treatment days was conducted in the artificial climate chamber of Nanjing University of Information Science and Technology from May to September 2020. Four levels of day/night temperature were set to 32℃/22℃, 35℃/25℃, 38℃/28℃ and 41℃/31℃. The air relative humidity was set at three levels: 50%, 70% and 90%（±5 percent point）, and the durations of treatment time were designed for 3, 6, 9 and 12 days. The treatments of day temperature 28℃/ night temperature 18℃, air relative humidity 50%±5pp were used as control (CK). The photosynthetic parameters, chlorophyll content and endogenous hormone content of terminal bud were measured systematically, and the floral differentiation of each node and final yield were observed. The results showed that: （1）the total amount of chlorophyll in cucumber leaves decreased with the increase of temperature and the extension of stress time. After 12 days of stress, chlorophyll a, chlorophyll b and carotenoid contents in cucumber leaves reached the lowest value, which decreased by 31.51%, 22.62% and 37.10% compared with CK, respectively. （2）The Pmax (maximum net photosynthetic rate), LSP (light saturation point) and AQE (apparent quantum efficiency) values of cucumber leaves decreased significantly with the deepening of high temperature and humidity stress. The LSP, AQE and Pmax values of cucumber leaves at 41℃ were the lowest, which were 48.78%, 40.00% and 43.04% lower than those of CK, respectively. In the range of 32−41℃, the Pmax values of cucumber leaves under 70% air relative humidity were higher than those under other humidity treatments, and the differences were small compared with CK. （3）In the process of flower bud differentiation, the contents of ZT (anti-zeaxin), ABA (abscisic acid) and GA3 (gibberellin) in cucumber terminal buds increased firstly and then decreased, while the contents of IAA decreased gradually with the growth of cucumber plant. The contents of ZT, IAA and GA3 in cucumber terminal buds decreased gradually with the increase of temperature and days of stress, while the changes of ABA content were on the contrary. At the end of 41℃, the contents of ZT, IAA and GA3 decreased by 47.37%, 26.38% and 83.65%, respectively, compared with CK, while the ABA content increased by 27.27% compared with CK. After 12 days of stress, the contents of ZT, IAA and GA3 reached the lowest values in the same period (0.07μg·g−1, 1.11μg·g−1, 0.75μg·g−1), while the ABA content reached the highest values in the same period (1.89μg·g−1).（4）High temperature and high humidity stress increased the node position of each female flower, but decreased the node rate of female flower and the number of flower buds. When treated with 70% air relative humidity, the nodes of female flowers were decreased, and the proportion of female flower nodes and the number of flower buds were increased. （5）High temperature and high humidity stress significantly reduced cucumber yield, and the yield of cucumber treated at 41℃ was 38.50% lower than that of CK. The study found that high temperature inhibited photosynthesis in cucumber leaves, disrupted the endogenous hormone balance in terminal buds, and reduced the number of female flower differentiation, resulting in lower final yield. [ABSTRACT FROM AUTHOR]

Surface dielectric barrier discharge can produce atmospheric low temperature plasmas, which has great application potential in the field of air purification.To investigate the effects of electrode gap on the generation of ozone and nitrogen oxides in surface dielectric barrier discharge, a two-dimensional fluid model was developed.The numerical simulation results indicated that the number and amplitude of current pulses decreased with the increase of electrode gap in the rising phase of microsecond-pulse voltage.Ozone density can be improved by decreasing the electrode gap, but increasing electrode gap was favorable for the improvement of ozone yield.NO density decreased with the increase of electrode gap, while the other nitrogen oxides remained almost unchanged.This study provided a comprehensive simulation analysis of the useful and harmful substances in the surface dielectric barrier discharge, which can provide some help for the design and optimization of the surface dielectric barrier discharge ozone generator. [ABSTRACT FROM AUTHOR]

‘Baoshi No.1', ‘Wanxiang' and ‘Fuwan No. 8' are the new longan varieties(lines)introduced from Fruit Research Institute of Fujian Academy of Agricultural Sciences to Nanning City, Guangxi in 2017. In order to study the local growth and development, flowering and fruiting regularity ‘Shixia' and ‘Guiming No.1', the main cultivars in Guangxi, were used as control to study the growth and development, yield, phenological period, flowering and fruit dropping regularity, and the relationship between the number of female flowers and temperature and humidity. The results were as follows: The plant growth and yield of the three introduced longan varieties(lines)after high grafting were similar to those of ‘Shixia'. The single panicle of ‘Baoshi No.1' was the heaviest, followed by ‘Fuwan No.8', and ‘Wanxiang' was similar to that of the two main cultivars; the fruit maturity stage of ‘Fuwan No.8' was the latest and the longest growth stage was 196 d, which was 15 d longer than ‘Guiming No.1'. The flowering stage of ‘Baoshi No.1' was the longest and ‘Wanxiang' was the shortest. The order of male and female flowers blooming of the three new varieties(lines)was “male-female-male-female-male”. The meeting time of male and female flowers of ‘Baoshi No.1' and ‘Fuwan No.8' was longer, which was 18-19 d. The three new longan varieties(lines)had three peak stages of fruit dropping in Nanning, and the fruit dropping mainly occurred in the second physiological fruit dropping stage in June. The results showed that the numbers of female flowers of three new longan varieties(lines)were closely related to the temperature and humidity before flowering. Within a certain range of temperature and humidity before and after flowering, higher temperature and lower air humidity were beneficial to female flower blooming of ‘Baoshi No.1' and ‘Fuwan No.8', while lower temperature and higher air humidity were beneficial to female flower blooming of ‘Wanxiang'. On the whole, the three introduced Fujian longan varieties(lines)can normally bloom and bear fruit in Guangxi, ‘Baoshi No.1' is earlier, ‘Fuwan No.8' is the latest, the meeting time of male and female flowers is long, and the fruit-dropping rate is low. [ABSTRACT FROM AUTHOR]

In order to understand the dynamic variations of photosynthetic capacity of Rhododendron to adapt to environmental factors in different seasons. Rhododendron delavayi, widely introduced and cultivated, was planted in a 2-gallon plastic basin in the open field. The dynamic variations of photosynthetic characteristics and influencing factors in different growth phases were investigated by the technique of gas exchange and chlorophyll fluorescence. The results were as follows: The growth cycle of R. delavayi were almost overlaps with photosynthetic variation at Kunming area. The variations of photosynthetic characteristics reflected the variations of growth cycle. In the net early growth period from May to July, the photosynthetic rate(Pn)increased rapidly, the stomatal conductance(Gs)was the decisive factor affecting (Pn). The relative humidity of air(RH)had a significant indirect effect on (Pn) by affecting Gs and transpiration rate(Tr). The (Pn) and growth could be stimulated by increasing RH at this phase. In the peak growth period from July to October, the RH, (Pn) and Gs of R. delavayi were high and stable. However, lower air temperature(AT)in this phase was a unique climate character in Kunming area. Low AT became an important factor affecting photosynthetic capacity at this phase, and increasing AT could improve (Pn) and promote the growth of R. delavayi. In the late growth phase after October, AT and RH decreased rapidly, stomata closed gradually, the maximum quantum efficiency of photosynthetic system Ⅱ(Fv/Fm)and (Pn) were declined. Gs and Fv/Fm were the main factors affecting photosynthesis at this stage. Our results can provide important references for the scientific cultivation and popularization of R. delavayi. [ABSTRACT FROM AUTHOR]

Three major production areas of Fuji apple, Linyi (in Shanxi province), Luochuan (in Shaanxi province) and Qixia (in Shandong province) were selected as the study region, based on 1 km gridded meteorological data, actual first flowering date data, and Chilling Hour Model (CHM) and Growing Degree Hour (GDH) data of the survey sample points in 2019-2020, the optimal chill/heat requirement at the first flowering date of apple was obtained using the gridded search method. Then, the daily air temperature characteristic values (Tmax, Tmin and Tavg) were divided into seven daily air temperature characteristic factor combinations, including single factor, double factors and triple factors, and the random forest algorithm (RF) was used to establish three regional daily chill/heat accumulation models with different daily air temperature characteristic factor combinations to select the optimal daily air temperature characteristic factor. On the basis of which, forecasting model of apple first flowering date was established based on the optimal daily air temperature characteristic factor by using RF algorithm, and the accuracy of the forecasting model was evaluated by independent actual first flowering date data. The results showed that: (1) the optimal chill/heat requirement at the first flowering date for apple in three regions were 730CH and 7350GDH in Linyi, 345CH and 4950GDH in Luochuan, and 520CH and 4450GDH in Qixia. (2) Among the seven combinations of daily air temperature characteristics, the three regional daily chill/heat accumulation models with the combination of Tmax, Tmin and Tavg had high accuracy in estimating daily chill/heat accumulation, and the RMSE between the estimated daily chill accumulation and the daily chill accumulation obtained from the CHM model was 0.97-2.50CH, and the RMSE between the estimated daily heat accumulation and the daily heat accumulation obtained from the GDH model was 1.73-15.76GDH. (3) When the daily chill/heat accumulation was estimated by forecast model of apple first flowering date, the RMSE between the estimated daily chill accumulation and the daily chill accumulation based on the CHM model ranged from 1.08 to 1.14CH, and the RMSE between the estimated daily heat accumulation and the daily heat accumulation based on the GDH model ranged from 2.03 to 3.74GDH. When the model was used to forecast first flowering date of apple, R² between the predicted and actual first flowering date was 0.92, and RMSE was 3.44d. The accuracy of the predicted first flowering date based on daily air temperature characteristic values was in overall agreement with that based on real hourly air temperature data, it indicated that the forecast model of apple flowering date established in this paper could effectively convert the input air temperature data from hourly scale to daily scale, which will have good application value and potential in the subsequent work on apple first flowering date forecasting. [ABSTRACT FROM AUTHOR]

A comprehensive understanding of the hydrological processes of thermokarst lakes on a seasonal scale is key to evaluating their environmental effects. In this study, a typical thermokarst lake was selected on the Qinghai-Tibet Plateau (QTP) and the meteorological and hydrological parameters were measured and calculated (2018—2020 to analyze the hydrological characteristics and environmental effects. The following results were obtained: ① Rainfall in spring recharges thermokarst lake water quickly and elevates lake water level rapidly; a power function was exhibited between lake water storage and water levels. ② The average annual lake evaporation and lake ice sublimation were 738 mm and 198 mm, respectively. Under the influence of rising air temperature, lake evaporation and ice sublimation may be increased in the future. ③ The ionic concentrations in lake water exhibited a high value in the initial and later periods of the warm season, and the self-purification of lake ice and geochemical processes resulted in different ion migration mechanisms. The hydrological elements exhibited obvious seasonal variation characteristics owing to the effect of local factors. Moreover, the hydrological processes involving thermokarst lake evolution can cause permafrost degradation, lakeshore collapse and receding, water environment deterioration, greenhouse gases release, soil salinization, and vegetation degradation. Thus, the environmental effects of thermokarst lakes should be evaluated on the entire QTP in future studies. [ABSTRACT FROM AUTHOR]

Based on the daily national meteorological data in autumn in 2021, relationships between meteorological factors and agricultural production in China were analyzed using statistical methods. The results showed that the national average air temperature in autumn in 2021 was 10.5℃, which was warmer than the same period from 1981 to 2010. The national average precipitation in autumn in 2021 was 157.9mm, which was the most since 1961. Additionally, the average precipitation in northwest China, north China and Huanghuai region was also the most respectively since 1961. The national average sunshine was 564.9 hours, which was the ninth from the bottom since 1961. The early frost in most of the agricultural areas of northeast China significantly occurred later than the normal year. The suitable sunshine and temperature in the most of autumn harvesting area in China were favorable for crop grain-filling, maturing, harvesting and drying. However, continuous rainy and cloudy weather in the early autumn in the eastern part of northwest China, most of north China and northern Huanghuai region disrupted the autumn crop harvesting. Therefore, the sowing date of winter wheat was delayed for 7-15 days due to delay of maize harvesting. The weather turned better in the middle and late autumn. Thus, the sowing speed of winter wheat was accelerated. At the end of autumn, the date of phenological stage of winter wheat in north China, Huanghuai and the east of northwest China was later for generally 7-25 days than the normal year, where the percentage of tillering stage for winter wheat was lower than that in the same period in the normal year and last year. The proportion of weak winter wheat seedling in China was higher than the same period in the normal year and last year. The soil moisture was suitable for autumn sowing in most of agricultural areas in south China, in which winter wheat and rapeseed sowing progressed well and was close to the normal year. [ABSTRACT FROM AUTHOR]