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【Objective】 Crop yield is inherently influenced by soil properties. This paper analyzes the spatial distribution of soil properties in Hetao Irrigation District (HID) and its relationship with crop yields, from which we propose how to optimize irrigation and fertilization to improve soil quality and crop yield in the district. 【Method】 The analysis was based on experimental data. The spatial distribution of soil physicochemical properties and crop yields in the district were analyzed using the classical statistics and geostatistics. Their correlations were used to help improve irrigation and fertilization. 【Result】 ①We found prominent issues such as high salinization, increased soil bulk density, and reduced crop yields, in the district. Notably, organic matter and nitrogen levels are relatively low, while available phosphorus is adequate and available potassium is abundant. Soil salinity showed considerable spatial variability, whereas organic matter, total nitrogen, available phosphorus, potassium, and crop yield coefficients showed moderate spatial fluctuations. Bulk density and soil pH, on the other hand, demonstrated only minor spatial variation. Bulk density and soil pH showed weak spatial variation. ②Spatially, soil salinity was pronounced in the central region, decreasing towards the periphery. Crop yield coefficients declined from the Southwest to the Northeast. Organic matter content increased from the West to the East. Soil bulk density, pH, total nitrogen and available phosphorus were the highest in the central region and the least in the East and the West. Low available potassium content was in the Southeast corner, with other areas featuring medium to high levels. ③Soil salinity was the main constraint to crop yields. ④Nitrogen and organic fertilization should be increased to improve soil fertility and crop yields. Specially, we recommend applying 225 kg/hm2 of urea and 3 393.7 kg/hm2 of organic fertilizer for heavily salinized and saline regions, 295.4 kg/hm2 of urea and 3 332.8 kg/hm2 of organic fertilizer for moderately salinized regions, and 365.1 kg/hm2 of urea and 1 280.9 kg/hm2 of organic fertilizer for slightly salinized and non-saline regions. In addition, drainage systems in the Northwest, South, and Southeast of the district should be improved to facilitate salt leaching. 【Conclusion】 The findings outlined in this paper establish a fundamental reference for enhancing soil salinity control and drainage management, as well as optimizing fertilization and irrigation to maintain and bolster crop yields in the Hetao Irrigation District.

This study evaluated the treatment efficiency of two selected fillers and their combination for improving the water quality of aquaculture wastewater using a packed bed biofilm reactor (PBBR) under various process conditions. The fillers used were nanosheet (NS), activated carbon (AC), and a combination of both. The results indicated that the use of combined fillers and the hydraulic retention time (HRT) of 4 h significantly enhanced water quality in the PBBR. The removal rates of chemical oxygen demand, NO2−─N, total suspended solids（TSS）, and chlorophyll a were 63.55%, 74.25%, 62.75%, and 92.85%, respectively. The microbiota analysis revealed that the presence of NS increased the abundance of microbial phyla associated with nitrogen removal, such as Nitrospirae and Proteobacteria. The difference between the M1 and M2 communities was minimal. Additionally, the microbiota in different PBBR samples displayed similar preferences for carbon sources, and carbohydrates and amino acids were the most commonly utilized carbon sources by microbiota. These results indicated that the combination of NS and AC fillers in a PBBR effectively enhanced the treatment efficiency of aquaculture wastewater when operated at an HRT of 4 h. The findings provide valuable insights into optimizing the design of aquaculture wastewater treatment systems. [ABSTRACT FROM AUTHOR]

The Hetao irrigation region is located in Inner Mongolia, China, within a dry and semi-dry region. This region suffers from poor agricultural productivity and environmental damage due to the presence of saline soil. To explore the growth of salty lands using a more environmentally friendly method, this research employed three eco-conscious amendments to improve the soil. These include flue gas desulfurization gypsum (S), humic acid (H), and biochar (C). During a two-year study, the amendments were utilized to enhance the soil quality for planting sunflowers. Humic acid was used prior to every seedling season, whereas the remaining two substances were only used once. These additions increased the soil's water-holding capacity, reduced soil salinity during sunflower growth, and improved the macroaggregate proportion. The most effective treatment for decreasing the soil's salt content after the seedling stage was the application of humic acid (0.6 t ha−1). Biochar (15 t ha−1) decreased the soil's bulk density (from 1.49 to 1.34 g cm−3) and mostly increased the sunflower seed yield up to 3133−3964 kg ha−1. Humic acid addition significantly increased the aggregate (>0.25 mm) content up to 27.88% after the experiment, but it led to a lower seed yield (2607−3686 kg ha−1). In 2019, the temperature was lower compared to 2018, which may have led to a reduction in the yield. However, these three amendments could potentially increase yields by more than conventional methods. These three environmentally friendly amendments are useful for improving saline soil and increasing yields. More studies are required to understand their impacts on larger areas and over extended periods. [ABSTRACT FROM AUTHOR]

Habitual dietary changes have the potential to induce alterations in the host's gut microbiota. Mandarin fish (Siniperca chuatsi), an aquatic vertebrate species with distinct feeding habits, were fed with natural feeds (NF) and artificial feeds (AF) to simulate the effects of natural and processed food consumption on host gut microbiota assemblages. The results showed that the alpha diversity index was reduced in the AF diet treatment, as lower abundance and diversity of the gut microbiota were observed, which could be attributed to the colonized microorganisms of the diet itself and the incorporation of plant-derived proteins or carbohydrates. The β-diversity analysis indicated that the two dietary treatments were associated with distinct bacterial communities. The AF diet had a significantly higher abundance of Bacteroidota and a lower abundance of Actinomycetota, Acidobacteriota, and Chloroflexota compared to the NF group. In addition, Bacteroidota was the biomarker in the gut of mandarin fish from the AF treatment, while Acidobacteriota was distinguished in the NF treatments. Additionally, the increased abundance of Bacteroidota in the AF diet group contributed to the improved fermentation and nutrient assimilation, as supported by the metabolic functional prediction and transcriptome verification. Overall, the present work used the mandarin fish as a vertebrate model to uncover the effects of habitual dietary changes on the evolution of the host microbiota, which may provide potential insights for the substitution of natural foods by processed foods in mammals. [ABSTRACT FROM AUTHOR]

Compared to the southern Tibetan Plateau, the northern part has been regarded as relatively lacking geothermal resources. However, there is no lack of natural hot springs exposed in beads along large-scale fracture systems, and research on them is currently limited to individual hot springs or geothermal systems. This paper focuses on the Wahongshan-Wenquan Fracture Zone (WWFZ), analyzes the formation of five hydrothermal activity zones along the fracture zone in terms of differences in hot water hydrochemical and isotopic composition, and then explores the hot springs' hydrothermal control in the fracture zone. The results show that the main fractures of the WWFZ are the regional heat control structures, and its near-north–south- and near-east–west-oriented fractures form a fracture system that provides favorable channels for deep hydrothermal convection. Ice and snow meltwater from the Elashan Mountains, with an average elevation of more than 4,500 m above sea level, infiltrates along the fractures, and is heated by deep circulation to form deep geothermal reservoirs. There is no detectable mantle contribution source heat to the hot spring gases, and the heat source is mainly natural heat conduction warming, but the "low-velocity body (LVB)" in the middle and lower crust may be the primary heat source of the high geothermal background in the area. The hot springs' hydrochemical components show a certain regularity, and the main ionic components, TDS, and water temperature tend to increase away from the main rupture, reflecting the WWFZ controlling effect on hydrothermal transport. In the future, the geothermal research in this area should focus on the hydrothermal control properties of different levels, the nature of fractures, and the thermal contribution of the LVB in the middle and lower crust. [ABSTRACT FROM AUTHOR]

To reduce the low-order vibrations of high-voltage transmission towers in response to strong winds, a tuned mass damper (TMD) that uses eddy current damping (ECD) with omnidirectional damping function (ECD-TMD) is proposed here. Compared with previous similar devices, the outstanding advantage of the proposed ECD-TMD lies in its use of non-contact ECD, structural simplicity, lack of internal friction, ability to sense micro-vibrations, and in the asymmetric cantilever pendulum structure that enables omnidirectional vibration suppression. Aero-elastic model wind tunnel test and field measurements were used for analyzing and validating the vibration responses of a 50-m-tall transmission tower with and without the proposed ECD-TMD. The results demonstrated that the proposed ECD-TMD reduced transmission tower's first-order bending vibrations along and across the direction of transmission line. For the mass ratio of approximately 2%, approximately 18–27% reduction of acceleration and 10–25% reduction of displacement occurred. Because the first-order resonance of the tower body in response to wind accounts for a small fraction of the background response, the addition of a TMD device suppresses structural wind vibrations in a limiter manner but can significantly increase the first-order bending damping ratio of the tower. [ABSTRACT FROM AUTHOR]