The aim of this study was to investigate the effects of different manures in combination with fulvic acid on NH₃ volatilization and vegetable yield in greenhouse soil. Two seasons of Chinese cabbage (Brassica chinensis L.) were grown in the greenhouse plots using variety Hanxiu, Shandaoqingcui, respectively. In the first growing season, there were a total of seven treatments: pig manure applied at rates of 30, 15, 9 t/hm² (P₃₀, P₁₅, P₉), chicken manure applied at rates of 5, 3 t/hm² (C₅, C₃) and sheep manure applied at rates of 11, 6 t/hm² (S₁₁, S₆), and a no fertilizer control (CK), respectively. After the first growing season, the second growing season was carried out, where pig manure, chicken manure and sheep manure were applied at rates of 31.9, 25.4, 31.3 t/hm² to maintain equal amount of nitrogen in each treatment, and NH₃ was collected by ventilatory method. The treatments in the second season included: totally fulvic acid (H), pig manure + fulvic acid (P_31.9H), pig manure (P_31.9), chicken manure + fulvic acid (C_25.4H), chicken manure (C_25.4), sheep manure + fulvic acid (S_31.3H), sheep manure (S_31.3) and no fertilizer control (CK). The two seasons consisted of treatments as follows: P₃₀-H, P₁₅-P_31.9H, P₉-P_31.9, C₅-C_25.4H, C₃-C_25.4, S₁₁-S_31.3H, S₆-S_31.3 and CK. NH₃ volatilization rate, accumulative NH₃ volatilization, yield and influencing factors of NH₃ volatilization were analyzed. The results showed that the NH₃ volatilization was mainly concentrated in the first 3 days after manure application. The cumulative volatilization of NH₃ with the single pig manure application treatments was higher than that with the single chicken and sheep manure application treatments, while it was higher in the fulvic acid treatments combined with chicken manure than that with sheep and pig manure. Sheep manure and pig manure treatments exhibited better yield than chicken manure treatments, and the combination with sheep manure and fulvic acid achieved the best yield of 27.48 t/hm². The content of NH₄ ⁺-N and NO₃ ^--N in the soil was correlated significantly with NH₃ volatilization from soil. Manures in combination with fulvic acid reduced the NH₃ volatilization from soil and increased vegetable yield. Considering both the vegetable yield and the NH₃ volatilization, it was concluded that the S₁₁-S_31.3H treatment performed best in this study.

To assess the effect of digested effluent of food waste on soil environment and crop growth when using drip irrigation, a pot experiment was conducted involving 2 soil matric potential thresholds (SMP) of -20 kPa (W) and -30 kPa (P), and 5 treatments of digested effluent percent (PDE) of 0% (0), 10% (1), 16.7% (2), 25% (3) and 33.3% (4) .Uniform NPK concentrations were dripped following the digested effluent at different concentrations.The study evaluated soil salinity (electrical conductivity of soil saturated paste, EC _e), soil nitrate and ammonium N concentration, and broccoli yield. The results showed that SMP had significant effects on soil EC _e. Compared to the P treatments, the W treatments decreased the EC_e of 13.0%. Soil EC _e increased with higher percent of digested effluent.The 33.3% treatment was 23.1%~46.8% higher than that of 0%~25% treatments. PDE significantly influence soil ammonium N content, 0% treatment was 2.2~3.0 times higher than the other treatments. Irrigation with digested effluent of food waste decreased the broccoli yield, especially the P₂, P₃ and P₄ treatments. The comprehensive analysis of soil salinity, soil inorganic N and broccoli yield reveals that there were no significant differences between the W and P, but decreased scores were found when the percent of digested effluent increased. The P₀ treatment had no significant higher score than the W₁, W₂ and P₁ treatments, but it did show a significant difference when compared to the W₃, W₄, P₂, P₃, and P₄ treatments. In conclusion, drip irrigation with digested effluent of food waste increased soil salinity, decreased soil ammonium nitrogen and broccoli yield, but -20 kPa still has advantage in decreasing soil salinity and increasing the applied percent of the digested effluent compared with -30 kPa.

To investigate the effects of water-fertilizer coupling with modified biochar on the physicochemical properties, enzyme activities and yield quality of soybean inter-root soil, a three-level orthogonal experiment was conducted with three factors (irrigation, nitrogen application and charcoal application). The results showed that: the amount of charcoal application had the most significant effect on soil physicochemical properties, followed by the amount of irrigation.Mild or moderate deficit irrigation could significantly increase soil microbial carbon and nitrogen content.For soil enzyme activities, the amount of irrigation had the most significant effect on soil catalase and phosphatase, and the highest activity was found under mild deficit irrigation conditions.Except for N-acyl-β-D-glucosidase, the enzyme activities were all increased with the increase of nitrogen and charcoal application, under the same amount of irrigation. Irrigation quantity had the most significant effect on protein and oil content of soybean kernel, and other quality indexes were not significantly affected by water, nitrogen and charcoal. Based on the results of the orthogonal test of the optimal soybean yield water, nitrogen and charcoal combination, the three factors in the order of irrigation, charcoal and nitrogen, and the optimal combination of soybean yield was W1N1B1 (i.e., moderate deficit irrigation, N fertilizer application of 75 kg/hm², and biochar application of 15 t/hm²). This study provides theoretical and technological support for the understanding of water, nitrogen and charcoal coupling, and for guiding the cultivation of high-quality, water-saving and high-efficiency soybeans in seasonal arid areas of Yunnan Province. This study provides theoretical basis and technical support for understanding the coupling relationship between water, nitrogen and carbon, and guiding the high-quality, high-yield and high-efficiency cultivation of soybean in seasonally arid areas of Yunnan.

The Maowusu Sandy Land area in Inner Mongolia, China, stands out as a successful example of ecological governance. Despite its abundant resources and favorable water-heat conditions compared to other sandy regions, it faces significant ecological vulnerability due to human activities and climate change. Balancing ecological security with socio-economic development is a critical research objective.This study, centered on the Maowusu Sandy Land region, establishes an ecological security-based evaluation system for comprehensive water resources carrying capacity. Using projection pursuit methods, the study assesses this capacity and identifies key factors influencing it through an obstacle degree model. The results show an overall fluctuating upward trend in water resources carrying capacity from 2000 to date, suggesting room for improvement. The area displays a spatial distribution pattern of higher capacity in the north and south and lower capacity in the center. Groundwater supply capacity, irrigation efficiency, and tertiary industry water usage are key strengths, while population, irrigation area, and urbanization hinder the enhancement of the carrying capacity. Coupled coordination among counties has consistently remained at a moderate level since the Tenth Five-Year Plan.

In order to solve the problems of high background leakage and excessive local pressure in irrigation water supply network, this study proposed an optimization method of pressure reducing valve layout of water supply network based on FMM-GA. The methodology utilizes MATLAB, EPANET, MATLAB-EPANET-Toolkit and PlatEMO platform. The pressure reducing valve was arranged in different zones for BIN in Spain, the pressure behind the valve was optimized. The cost and leakage reduction effect of different zoning schemes were taken as the control index to select the optimal scheme. The results show that: The optimal scheme (divided into 5 zones) reduces the leakage rate of the entire pipe network to 7.45%, which is 20.04% lower than the initial network. It also reduces the leakage cost up to 114€/d, allowing for cost recovery and achieving profitability within the service life of the pressure reducing valve. Additionally, the optimal scheme enables the pressure management of the entire network system, improving the stability and reliability of the pipe network. It is beneficial to reduce network accidents. Therefore, the pressure reducing valve layout optimization of irrigation water supply network based on FCM-GA is a safe, low cost and high efficiency method for leakage reduction and pressure control. It can effectively reduce irrigation water cost and better realize water-saving irrigation.

The filter is a crucial equipment for maintaining the proper operation of a micro irrigation system, and head loss and filtering efficiency are key indicators for evaluating its performance. To investigate the hydraulic performance and filtering performance of the pre-pump filter-float mesh rotary filter, this study employs variance analysis, range analysis, and main effect multiple comparison method to compare and analyze the head loss and filtering efficiency of the float mesh rotary filter under five different sediment concentrations and five different flow rates when the filter mesh aperture is 0.150 mm. The aim is to determine the optimal working condition under the experimental conditions. The results indicate that: flow rate has a greater impact on head loss than sediment concentration. Sediment concentration has a greater influence on filtering efficiency. Both head loss and filtering efficiency increase with an increase in sediment concentration and flow rate. Thus, it can be concluded that the optimal working condition is a flow rate of 930 L/h with a sediment concentration of 2.0 g/L. Under these conditions, the corresponding head loss is 0.281 m while achieving a filtering efficiency of 84.01%. This ensures good filtration effectiveness while minimizing energy consumption for efficient irrigation practices aimed at reducing emissions.

Improving the effective rainfall utilization rate is one of the main ways to save irrigation water in rice cultivation.To further improve the rainfall utilization rate, a reinforcement learning method for irrigation decisions considering weather forecasting is used to construct a water balance model and rice crop water production function to simulate the real environment and rice growth of farmland. The measured meteorological data and weather forecast data of Dali station from 2012 to 2020 were collected to train the intelligent irrigation decision-making model, and the model was applied to Erhai irrigation district in Yunnan Province. According to the experimental research and model training, the daily rainfall forecasting performance of Erhai irrigation district was acceptable and that potentially uncertain rainfall exists for learning and utilization. Compared with conventional irrigation decision-making, the use of reinforcement learning irrigation decision-making can reduce the irrigation frequency by 0.2 times per year, save irrigation water by 6.5 mm, with the save water rate of 6.0%. Moreover, it increases rainfall utilization rate by 3.0%, and reduces drainage by 6.2 mm with no production loss caused. Therefore, smart irrigation decision-making can effectively improve rainfall utilization and save irrigation water while considering production.

As a novel type of irrigation filtration device, the pre-pump micro-pressure mesh filter has the advantages of simple structure, high adaptability and low energy consumption. To investigate the operation state of the internal flow field of the pre-pump micro-pressure mesh filter, this paper adopts the methods of physical model test, numerical calculation and theoretical analysis to analyze the hydraulic performance and water movement state of the pre-pump micro-pressure mesh filter at different flow rates (5, 8, 11, 14 and 17 m3/h) under the condition of clear water from a microscopic point of view. The results indicate that the standard k-ε model can be used as a turbulence model to simulate the clear-water flow field of the pre-pump micro-pressure mesh filter. The flow velocity distribution inside the filter mesh is not uniform, and presents different forms of "fire candle" morphology with the flow rate.The range of influence of the outlet on the inside of the filter increases with the increase of flow rate. High-pressure and negative-pressure areas appear simultaneously inside the filter, and the bottom of the screen is the main location of head loss. The research results can provide theoretical and technical support for the numerical simulation and structural optimization of turbid water in the pre-pump filtration equipment.

In order to analyze the vibration characteristics of vertical axial flow pump in saddle region under blade Angle, the numerical simulation method of CFD software CFX and pump device test were used to validate the accuracy of the calculation results. The deformation, vibration characteristics, pressure pulsation and aperiential force of the pump section under 3 blade Angle and 4 flow rates were numerically calculated. Additionally, the vibration performance of the saddle area of the pump is tested by experiments. The results indicate that there is a saddle zone between 0.30 Q_BEP and 0.60 Q_BEP . The main factor that causes the vibration of the pump section in the saddle zone is the interference of the dynamic and static interface between impeller and guide vane. To ensure the stability of the pump during operation, the minimum flow rate should exceed the flow rate in the reinforced saddle region defined in this paper. When the pump device is running in the saddle area, a smaller blade setting angle leads to greater stability.

To investigate the impact of the two-way flow channel confluence angle on the hydraulic performance of the emitter, numerical simulations were conducted to analyze the hydraulic performance and the change in blockage resistance of the two-way flow channel emitter across six groups of confluence angles. Research results show that: with the increase in the two-way flow channel convergence angle, the emitter flow coefficient and the flow index gradually increased. For convergence angles of 45°, 60°, 90°, 105°, the emitter flow index was in the vicinity of 0.5, when the convergence angle of 135°, 165°, emitter flow index exceeded 0.7; The two-way flow path of the emitter has a main flow and a swirl zone.As the convergence angle increases, the low-speed vortex area in the flow channel is significantly reduced, the water is less likely to separate from the side wall.The trajectory of solid particles in the flow channel with the flow channel structure changes very obvious. At convergence angles of less than 90°, particles are more likely to enter the vortex zone with a swirling mass motion and are mainly found in the runner unit near the inlet of the runner, which has a high probability of blocking the runner. When the angle of convergence of the water flow is greater than 90°, the water flow has a strong ability to carry sand and the particles are easily discharged from the flow channel with the water flow, the residence time of the particles in the flow channel is reduced, the flow channel resistance to blockage is enhanced. Two-way flow channel emitters demonstrate relatively excellent hydraulic performance and blockage resistance at a confluence angle of 105°, which can be given priority in two-way emitter flow channel design.

In response to the lack of appropriate irrigation quotas and phytonutrient application systems in the process of promoting drip irrigation technology for maize and improving water and fertilizer use efficiency in northern Ningxia, we explored the effects of different irrigation quotas and phytonutrient application amounts on maize growth, quality and yield in the context of water conservation and efficiency improvement. We set up three irrigation quotas (W1=2 100 m³/hm², W2=2 700 m³/hm², W3=3 300 m³/hm²) and three phytonutrient application rates (P1: 42 g/hm², P2: 63 g/hm², P3: 84 g/hm²). The results showed that: irrigation quota, phytonutrients and their interaction had highly significant (P<0.01) effects on maize plant height, leaf area index, crude protein, ash, and water use efficiency. Irrigation quota and phytonutrients had highly significant (P<0.01) effects on maize yield, and their interaction had significant (P<0.05) effects on maize yield. Maize kernel yield was significantly increased with increasing irrigation quota and phytonutrients, and the W3P3 treatment had the highest yield of 9 546.75 kg/hm². The results of the comprehensive evaluation based on entropy weight-TOPSIS showed that the irrigation quota of 3 300 m³/hm² and phytonutrient application of 84 g/hm² demonstrated the highest degree of fit and the best evaluation results. In summary, the recommended irrigation quota for drip-irrigated maize in northern Ningxia in dry years is 3 300 m³/hm², and plant nutrient application is 84 g/hm².

In order to explore the effects and variations of different drought stresses on the water use efficiency of summer soybean in lime concretion black soil and yellow tide soil at different growth stages. Based on the drought test of barrel planting at Wudaogou experimental station in 2022.Three drought levels of light drought, medium drought and severe drought and drought-free control (CK) of summer soybean were set up through water control at the branching stage, pod stage and drum grain maturity stage of summer soybean, and the effects and variations of different drought stresses in different growth periods on water consumption, yield and water use efficiency (WUE) of summer soybean in two types of soil were analyzed. The results showed that: ①The water consumption of summer soybean in both types of soil decreased with the aggravation of drought, and the decrease of severe drought was the most significant. The water consumption in the black soil of sand ginger was smaller than that of the control group, and the water consumption of yellow aquic soil except for the light drought at the branching stage was lower than that of the control group, and the water consumption reduction level was lower than that of the lime concretion black soil except for the light drought in the drum grain maturity stage. ②The two types of soil had the strongest impact on yield, and the severe drought and yield reduction were the most serious during the drum grain ripening stage. The yield reduction rate of different drought levels in the pod stage of yellow tide soil was lower than that of lime concretion black soil, and the yield reduction rate of lime concretion black soil at different drought levels in the branching stage was lower than that of yellow tide soil. ③ WUE during pod stage and drum grain maturity stage of the two soils showed a significant decreasing trend with the intensification of drought. WUE decreased significantly under the influence of severe drought, and severe drought had the most serious impact on WUE in the drum grain maturity stage. There were differences in the level of yield reduction due to drought at different growth stages, so that the WUE of yellow tide soil in the pod stage was higher than that of lime concretion black soil in each treatment group, and the WUE of yellow tide soil in the branching stage was lower than that of lime concretion black soil.

Zeolite is an effective soil conditioner. Investigating the impact of zeolite on water conservation, fertilizer management, and yield improvement is of great importance in ensuring food security, water safety, and ecological sustainability. Based on research achievements of relevant experts and scholars worldwide, this paper analyzes the effect of zeolite on water saving,and summarizes the effect of zeolite on ammonia volatilization and N leaching. Furthermore, it concludes the research findings regarding the role of zeolite in enhancing crop productivity.The outcomes of this study provide a theoretical basis for further enhancing the quantitative research and targeted research in the future.

There is a lack of targeted evaluation methods for the suitability of irrigation water sources in arid and semi-arid areas. Existing evaluation methods tend to have limited applicability and rely on single indicators, which restricts their usefulness across different water sources. Therefore, this paper takes arid and semi-arid areas as the research object to explore the evaluation methods that can be applied to the suitability of different irrigation water sources. The suitability evaluation index system of irrigation water source was constructed by comprehensively considering factors such as the available supply of irrigation water source, the timeliness of irrigation water supply, the consumption of water lifting energy, and the irrigation water temperature. The group decision entropy optimization method algorithm was introduced to determine the combined weight of the evaluation index. Taking three available irrigation water sources in Pingluo County of Ningxia as a typical case, the TOPSIS method was used to comprehensively evaluate the irrigation suitability of three different water sources from April to September, combined with the constructed evaluation index system and weight determination method. The closeness degree values of Yellow River water and drainage in Pingluo County from April to September were all greater than 0.31, suggesting their suitability for irrigation. The close degree value of groundwater in April is only 0.241 2, which is not suitable for irrigation. Still, the closeness degree value of groundwater from May to August exceeds 0.31, which is suitable for irrigation, and is consistent with the actual situation of Yinbei Irrigation District in Ningxia. The evaluation index system constructed in this paper and the introduced combination weight determination method (group decision entropy optimization-CRITIC algorithm) are suitable for the suitability evaluation of irrigation water sources in arid and semi-arid areas.

In order to realize scientific irrigation of winter wheat in Jiangsu Province, improve the efficiency of agricultural water use, clarify the spatial and temporal characteristics of winter wheat water demand and climatic influences in Jiangsu Province, and provide scientific and technological support for the province's irrigation management of winter wheat and the efficient use of agricultural water resources, this paper utilized the meteorological data related to the 2013-2022 winter wheat season in a total of 12 areas in Jiangsu Province. The water demand of winter wheat in Jiangsu Province in the past decade was calculated by the Penman-Montieth method. The spatial and temporal changes in the water demand of winter wheat in Jiangsu Province in the past decade were analyzed by the Pearson correlation analysis method, as were the characteristics of the water demand and the meteorological factors affecting the winter wheat in Jiangsu Province. During the past ten years, average annual temperature, average daily humidity, surface temperature, precipitation, evaporation, and average sunshine hours in Jiangsu Province have all shown a general upward trend, and total solar radiation has shown a decreasing trend. The average value of winter wheat water demand in Jiangsu Province is 451.82~692.50 mm, and the province's winter wheat water demand shows a decreasing trend in different years of the present field period, with an inter-annual variation range of 540.19~646.70 mm, and the province's wheat water demand shows a decreasing trend from northwest to southeast. In most areas of Jiangsu Province, the minimum winter wheat water demand intensity occurs in January, and the maximum water demand intensity occurs in May-June during the tasseling period and grouting period. Winter wheat water demand in Jiangsu Province exhibits a negative correlation with average annual rainfall and average daily humidity, and a positive correlation with average annual water surface evaporation, average annual sunshine hours and average annual air temperature in Jiangsu Province. Among these factors, average daily humidity, average annual water surface evaporation and average annual air temperature have the most obvious influence on winter wheat water demand. Moreover, the overall slightly decreasing trend of winter wheat water demand during the whole reproductive period in the last decade may be due to its significantly higher negative correlation with mean daily humidity. In conclusion, in the past ten years, winter wheat water demand in Jiangsu Province has a decreasing trend year by year, and decreasing from northwest to southeast, and the province's average daily humidity, average annual evapotranspiration from the water surface, the average annual temperature is the main influencing factor of the change of winter wheat water demand in recent years.

A SEBAL model was established suitable for inversion of remote sensing on ground surface evapotranspiration in Ningxia. Based on the SEBAL model, the surface evapotranspiration of Ningxia was inverted, and its accuracy was validated by using open datasets. The results indicate that the mean value of correlation coefficient R² is maintained above 0.80 and 0.79 by P-M model and water surface evaporation data of weather stations, respectively. The mean value of R² is maintained above 0.90 by MOD16 evapotranspiration product verification, and the mean value of root mean square error is 1.03 and the mean value of deviation is 1.76. Spatially, it basically presents a trend of increasing from the northern plain to the southern mountain area. Temporally, evapotranspiration shows an overall upward trend from 2001 to 2021. The capacity of surface evapotranspiration of different land use follows the following order: forest land>cultivated land>water area>grassland>urban construction land>bare land. The average evapotranspiration is 10.18 mm/d, 8.18mm/d, 8.12 mm/d, 7.83 mm/d, 7.70 mm/d, 7.48 mm/d, respectively. The results show that the surface evapotranspiration obtained based on the SEBAL model has higher accuracy, higher resolution and wider applicability in the early dry and semi-early dry areas.