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Surface soil hydraulic properties play critical roles in controlling water infiltration, evaporation, and soil water storage, in‐turn affecting the evolution of soil pore structure in cultivated desert soils of arid areas. The variability in soil pores and hydraulic properties caused by conversion of native semidesert soils to agroforestry use alters soil water storage and water budget in the desert–oasis ecotone. The objective of this study was to investigate that land use conversion alters surface soil hydraulic properties and enhances the contribution of soil macropores to water flow in the Linze desert–oasis ecoregion. Water infiltration and soil pores characteristics with nine replicates were measured using a disc tension infiltrometer across four habitat types (Haloxylon ammodendron shrublands, Populus gansuensis forests, Medicago sativa Linn grasslands, and Zea mays croplands) during the growing season. Soil properties and hydraulic conductivity characteristics clearly varied across the four habitat types. Saturated hydraulic conductivity was 0.177, 0.126, 0.118, and 0.031cm min⁻¹ in the forest, grassland, shrubland, and cropland, respectively, with the corresponding average soil moisture being 7.6, 6.7, 0.9, and 19.2%. Clay content, bulk density, and initial soil moisture were the key soil physicochemical properties affecting saturated hydraulic conductivity (Kₛ). The macropores (> 0.5 mm in radius) accounted for 15–60% of total water flow, while 0.25–0.5 mm pores contributed to 12–24% across the four habitat types. The contribution of >0.5 mm pores to water flow in the forest was 3.3–4.0‐times greater than in shrubland and cropland, due to greater soil macroporosity (58 cm⁻³ cm³) and undisturbed soil pore structure. Land use conversion has a positive impact on soil properties, structure features, and soil hydraulic properties, and as a consequence, enhance the complexity of water exchange in the arid areas.

The commonly applied pedotransfer functions (PTFs), which predict soil hydraulic properties (SHPs) from easily measured soil properties such as texture information, often account only for capillary...

Obtaining accurate soil moisture data from sensors in automated monitoring networks is critical as these data are increasingly used for research in soil hydrology, ecohydrology, and related disciplines. One of the earliest such networks is the Oklahoma Mesonet, which monitors soil matric potential using heat dissipation sensors. Various calibration equations have been proposed for those sensors, and there is a need to compare and validate the performance of those equations, especially for matric potentials < –150 kPa. A laboratory experiment was conducted in silt loam soil using a sand-kaolin box and a pressure plate apparatus with matric potentials ranging from 0 to –1500 kPa. The calibration equations included Starks’ equation, Flint et al.’s equation, Schneider et al.’s equation, and a new logistic equation. The upper limit of the sensors was -9 kPa, and the sensors remained responsive at -1500 kPa matric potential. The logistic equation produced the lowest root mean squared error (34 kPa), followed by Flint et al.’s equation (192 kPa), Starks’ equation (295 kPa), and Schneider et al.’s equation (463 kPa). After recalibration of the coefficients in the three preexisting equations, their performances improved, with all RMSE values ≤ 251 kPa; however, the logistic equation still provided superior accuracy. The logistic equation effectively removed an ∼ 0.02 cm³ cm⁻³ positive bias in soil water content that resulted from use of the original parameterization of Schneider et al.’s equation. This logistic equation is recommended for use with past and future data from the Oklahoma Mesonet’s heat dissipation sensors.

Soy protein isolate (SPI) has promising applications in various food products because of its excellent functional properties and nutritional quality. The structural and emulsifying properties of covalently modified SPI by (-)-epigallocatechin-3-gallate (EGCG) were investigated.; Results: SPI was covalently modified by EGCG under alkaline conditions. SDS-PAGE analysis revealed that EGCG modification caused crosslinking of SPI proteins. Circular dichroism spectra demonstrated that the secondary structure of SPI proteins was changed by EGCG modification. In addition, the modifications resulted in the perturbation of the tertiary structure of SPI as evidenced by intrinsic fluorescence spectra and surface hydrophobicity measurements. Oil-in-water emulsions of modified SPI had smaller droplet sizes and better creaming stability compared to those from unmodified SPI.; Conclusion: The covalent modification by EGCG improved the emulsifying property of SPI. This study therefore provided an innovative approach for improving the emulsifying properties of proteins. © 2018 Society of Chemical Industry.; © 2018 Society of Chemical Industry.

Concern is increasing regarding the environmental impact of the high usage rate and intensive release of antibiotics used for human and animal therapy in major urban areas of China. In the present study, regional environmental distribution simulations and risk assessments for 3 commonly used fluoroquinolones in the Wenyu River catchment were conducted using a typical catchment model widely used in Europe. The fluoroquinolone antibiotics investigated (ofloxacin, norfloxacin, and ciprofloxacin) are consumed at high levels for personal health care in China. These antibiotics were simulated in the aquatic environment of the Wenyu River catchment across the Beijing City area for annual average concentrations, with regional predicted environmental concentrations (PECs) of approximately 711 ng/L, 55.3 ng/L, and 22.2 ng/L and local PECs up to 1.8 µg/L, 116 ng/L, and 43 ng/L, respectively. Apart from hydrological conditions, the concentrations of fluoroquinolones were associated closely with the sewage treatment plants (STPs) and their serving population, as well as hospital distributions. The presence of these fluoroquinolones in the catchment area of the present study showed significant characteristics of the occurrence of pharmaceuticals in the aquatic environment in an urban river, with typical “down-the-drain” chemicals. Significantly high concentrations of specific antibiotics indicated non-negligible risks caused by the intensive use in the local aquatic environment in a metropolitan area, particularly ofloxacin in upstream Shahe Reservoir, middle stream and downstream Qing River, and Liangma River to the Ba River segment. Specific treatment measures for these pharmaceuticals and personal care products in STPs are required for such metropolitan areas. Environ Toxicol Chem 2015;9999:1–7. © 2015 SETAC

Non-point source pollution is a key issue in integrated river basin management around the world and has resulted in water contamination, aquatic ecology deterioration and eutrophication. Xin'anjiang catchment is the key drinking water source area for Hangzhou City, China. A promising model (Soil and Water Assessment Tool) was applied to assess the non-point source pollution and its effect on drinking water. Sensitivity analysis of model parameters was carried out using the Sequential Uncertainty Domain Parameter Fitting 2 sensitivity technique. Water discharge, sediment, total nitrogen and total phosphorus load processes from 2000 to 2010 were simulated, and the spatial distributions of non-point source pollutants were evaluated at the catchment and administrative country levels. The results show that the hydrological parameters of the Soil and Water Assessment Tool were dominantly sensitive for non-point source pollution simulation, including CN2, RCHRG_DP, ALPHA_BF, SOL_AWC, ESCO and SOL_K and the characteristic parameters of sub-basins (viz. HRU_SLP and SLSUBBSN). Also, water quality parameters (viz. CH_EROD, NPERCO, RSDCO and PPERCO, PHOSKD, etc.) have a significant effect on nutrients. The model performance was very satisfactory, especially for runoff, sediment and total phosphorus simulation. The non-point source pollutant load increased from 2001 to 2010 in the whole catchment. Total nitrogen load increased from 3428tons (0.59tonkm(-2)) to 7315tons (1.25tonkm(-2)), and total phosphorus load increased from 299tons (0.05tonkm(-2)) to 867tons (0.15 tonkm(-2)). The contribution of rice land was the largest, accounting for nearly 95%, followed by tea garden (3.56%), winter wheat (1.37%), forest (0.07%) and grassland (0.02%). Moreover, She County and Xiuning County contributed more than half of the non-point source pollutants. This study was expected to provide a method and reference for non-point source pollution quantification and to support water quality management implementation in China. Copyright (c) 2012 John Wiley & Sons, Ltd.

A novel thermosensitive adhesive was synthesized by the esterification reaction of multihydroxyl Pluronic L-31 with 3,4-dihydroxy-l-phenylalanine and l-arginine. Pluronic L-31–DOPA–arginine derivative (PDA) gels, rapidly formed in situ with horseradish peroxidase and hydrogen peroxide, were used to explore the performance of efficient tissue adhesives. The results of their adhesive strength on porcine skin demonstrate that the structure of the polymers and temperature influenced the adhesiveness to tissue of the polymers. Compared with the PDAs at 25 °C, the PDAs at 37 °C showed superior adhesive strength. The attractive performance of the PDA gels were demonstrated by this study's results, which suggest biomedical applications in tissue-adhesive devices in the future. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 44729.

Climate change may significantly affect the hydrological cycle and water resource management, especially in arid and semi-arid regions. In this paper, output from the Providing Regional Climates for Impacts Studies (PRECIS) regional climate model were used in conjunction with the Soil and Water Assessment Tool (SWAT) to analyse the effects of climate change on streamflow of the Xiying and Zamu rivers in the Shiyang River basin, an important arid region in northwest China. After SWAT model calibration and validation, streamflow in the Shiyang River Basin was simulated using the PRECIS climate model data for greenhouse gas emission scenarios A2 (high emission rate) and B2 (low emission rate) developed by Intergovernmental Panel on Climate Change. Monthly streamflow and hydrological extremes were compared for present-day?years (19611990), the 2020s (20112040), 2050s (20412070) and 2080s (20712100). The results show that mean monthly streamflow in Shiyang River Basin generally increased in the 2020s, 2050s and 2080s between 0.76.1% at the Zamu gauging station and 0.14.8% at the Xiying gauging station. The monthly minimum streamflow increased persistently, but the maximum monthly streamflows increased in the 2020s and slightly decreased in the 2050s and 2080s. This study provides valuable information for guiding future water resource management in the Shiyang River Basin and other arid and semi-arid regions in China. Copyright (c) 2011 John Wiley & Sons, Ltd.

Flow regime characteristics (magnitude, frequency, duration, seasonal timing and rates of change) play a primary role in regulating the biodiversity and ecological processes in rivers. River classification provides the foundation for comparing the hydrologic regimes of rivers and development of hydro-ecological relationships to inform environmental flow management and river restoration. This paper presents a classification of natural flow regimes and hydrologic changes due to dams and floodgates in the Huai River Basin, China, in preparation for an environmental flow assessment. The monthly natural flow regime of 45 stations in the upper and middle Huai River Basin were simulated for the period 19632000, based on the hydrological model SWAT (Soil and Water Assessment Tool). Six classes of flow patterns (low or high discharge, stable or variable, perennial or intermittent, predictable or unpredictable) were identified based on 80 hydrologic metrics, analysed by hierarchical clustering algorithms. The ecologically relevant climatic and geographic characteristics of these flow classes were tested for concordance with, and to strengthen, the hydro-ecological classification. The regulation of natural flow patterns by dams and floodgates changed flows at some locations within each flow class and caused some gauges to shift into another class. The research reported here is expected to provide a foundation for development of hydro-ecological relationships and environmental flow methods for wider use in China, as well as setting a new scientific direction for integrated river basin management in the Huai River Basin. Copyright (c) 2011 John Wiley & Sons, Ltd.

Huai River Basin, as the sixth largest river basin in China, has a high-regulated river system and has been facing severe water problems. In this article, the changing patterns of runoff and precipitation at 10 hydrological stations from 1956 to 2000 on the highly regulated river (Shaying River) and less-regulated river (Huai River) in the basin are evaluated at the monthly, seasonal and annual scales using the Mann-Kendall test and simple linear regression model. The results showed that: (1) No statistically significant trends of precipitation in the upper and middle Huai River Basins were detected at the annual scale, but the trend of annual runoff at Baiguishan, Zhoukou and Fuyang stations in Shaying River decreased significantly, whereas the others were not. Moreover, the decreasing trends of runoff for most months were significant in Shaying River, although the trend of monthly precipitation decreased significantly only in April in the whole research area and the number of months in the dry season having significantly decreasing trends in runoff was more than that in the wet season. (2) The rainfall-runoff relationship was significant in both highly regulated river and less-regulated river. In regulated river, the reservoirs have larger regulation capacity than the floodgates and thus have the smaller correlation coefficient and t-value. In Huai River, the correlation coefficients decreased from upper stream to downstream. (3) The regulation of dams and floodgates for flood control and water supply was the principal reason for the decreasing runoff in Huai River Basin, although the decreasing precipitation in April in this basin was statistically significant. The findings are useful for recognizing hydrology variation and will provide scientific foundation to integrated water resources management in Huai River Basin. Copyright (C) 2010 John Wiley & Sons, Ltd.