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AbstractSense of agency refers to the subjective perception of initiating and controlling one’s actions and their consequences within both individual and social contexts. It encompasses not only self-agency, where individuals feel in control of their actions from a first-person perspective, but also other-agency, where individuals comprehend the control exerted by others over their actions through mentalizing. This study explores the characteristics of implicit self-agency and other-agency in social interaction contexts using an interval estimation paradigm. The results indicate that voluntary actions lead to a temporal binding effect in individual contexts. Moreover, the reported intervals generated by the self in individual contexts are shorter than those in human-human and human-robot interaction contexts, suggesting a reduction in self-agency within social interaction contexts. Conversely, temporal intervals in human-human interactions are reported to be shorter than those in individual and human-robot interactions, indicating that other-agency remains unaffected. These findings highlight the distinct effects of social interaction contexts on self-agency and other-agency, offering novel empirical insights into human interaction behavior. [ABSTRACT FROM AUTHOR]

• The left caudate, left cerebellum, and right precuneus are the core brain regions responsible for time estimation. • The temporal reproduction task induces higher connection between the left caudate and left precuneus. • The left caudate plays a key role in the neural network of time estimation. Time estimation is fundamental for human survival. There have been increasing studies suggesting that distributed brain regions, such as the basal ganglia, cerebellum and the parietal cortex, may contribute to a dedicated neural mechanism of time estimation. However, evidence on the specific function of the subcortical and cortical brain regions and the interplay of them is scare. In this work, we explored how the subcortical and cortical networks function in time estimation during a time reproduction task using functional MRI (fMRI). Thirty healthy participants performed the time reproduction task in both auditory and visual modalities. Results showed that time estimation in visual and auditory modality recruited a subcortical-cortical brain network including the left caudate, left cerebellum, and right precuneus. Besides, the superior temporal gyrus (STG) was found essential in the difference between time estimation in visual and auditory modality. Using psychophysiological interaction (PPI) analysis, we observed an increase in the connection between left caudate and left precuneus using the left caudate as the seed region in temporal reproduction task than control task. This suggested that the left caudate is the key region connecting and transmitting information to other brain regions in the dedicated brain network of time estimation. [ABSTRACT FROM AUTHOR]

The sense of agency (SoA) refers to the feeling of being in control of one's actions and the subsequent consequence of these actions. Emotional context seems to alter the strength of sense of agency. The present study explored the influence of acute psychosocial stress on the SoA by means of the Trier Social Stress Test (TSST). Self-assessment manikin (SAM) and objective physiological indicators (e.g. heart rate, electrodermal activity, and salivary cortisol levels) were utilized to evaluate the effect of the TSST. We also employed the temporal binding effect as an implicit assessment of the participant's SoA. The results indicated that the stress level of the experimental group after TSST was significantly higher than the control group, whilst the temporal binding scores of the experimental group decreased after TSST manipulation. In short, acute psychosocial stress with intense emotional arousal weakened the sense of agency. [ABSTRACT FROM AUTHOR]

In this study, we explored the complexities of document-level event extraction, a process that involves identifying multiple events and their associated arguments within a document. The primary challenges include (1) the distribution of event arguments across numerous sentences, resulting in long-distance dependencies, and (2) the complex relationships between multiple events due to the overlapping and dispersion of event arguments throughout the document. To address these issues, we propose the Binary Contrastive Generation (BCG) method. BCG utilizes binary auto-regressive generation in both the original and reversed sequences to learn binary-directed interdependency, thereby capturing the long-distance dependency of dispersed event arguments. To handle intricate multi-event relationships, BCG enhances the global semantic representation of multiple events by extraction-oriented contrastive learning. Specifically, event representations derived from identical event arguments in varying sequences are deemed positive pairs, while those from different event arguments in the same sequence are classified as negative pairs. Experimental results on three public datasets demonstrate that BCG outperforms existing methods, achieving an increase of 2.6 in absolute F1 score. Further analysis revealed that BCG effectively models the dependency of dispersed event arguments and enhances the semantic representation of multiple events. [ABSTRACT FROM AUTHOR]

• Self-related information modulates the temporal binding effect. • The impact of self-related information may be more prominent during the outcome binding stage. • Post-hoc explanation plays an important role in the temporal binding effect. Sense of agency (SoA) refers to the subjective experience of controlling one's actions and their subsequent consequences. The present study endeavors to investigate the impact of how different degrees of self-related stimuli as action outcomes on the sense of agency by observing the temporal binding effect. Results showed that self-related sound significantly altered temporal binding, notably influencing outcome binding. A post-hoc explanation model effectively elucidated the role of self-related information in the formation of the sense of agency. [ABSTRACT FROM AUTHOR]

Oxidative stress and inflammation play important roles in the neuronal injury caused by intracerebral hemorrhage (ICH). Uric acid (UA), an important natural antioxidant, might reduce the neuronal injury caused by ICH. Delineating the relationship between UA and ICH will enhance our understanding of antioxidative mechanisms in recovery from ICH. We conducted a retrospective study of 325 patients with acute supratentorial ICH to investigate the relationship between serum UA levels and hematoma volumes and prognosis. A hematoma volume of ≥30 mL was defined as a large hematoma. An unfavorable outcome was defined as a modified Rankin scale score of 4–6 on day 30. The serum UA level was significantly lower in the patients with a large hematoma volume (median, 306 μmol/L; 25th to 75th percentile, 243–411 μmol/L) than in those with a small hematoma volume (median, 357 μmol/L; 25th to 75th percentile, 271–442 μmol/L; P = 0.012). Similarly, the unfavorable outcome group had had lower serum UA levels (median, 309 vs. 363 μmol/L; P = 0.009) compared with the favorable outcome group. The results of the multivariate logistic analysis indicated that a lower serum UA level was associated with a larger hematoma volume (odds ratio, 0.996; P = 0.006) and an unfavorable outcome (odds ratio, 0.997; P = 0.030). The results from the present study have indicated that in patients with acute supratentorial ICH, a low serum UA level might indicate that the patient has a large hematoma volume and might be a risk factor for a poor day 30 functional prognosis. [ABSTRACT FROM AUTHOR]

Highlights • A coupled model was developed for water and solute transport in furrow irrigation. • The surface and subsurface processes were coupled with the iterative method. • The model was validated by comparing its simulated results with measured data. • Numerical tests were conducted for evaluating the accuracy and efficiency of the model performance. Abstract For optimal water and fertilizer management under furrow irrigation, it is important to understand the water and solute dynamics on the land surface and in the subsurface. An efficient mathematical tool is required to describe these dynamic processes. We propose a coupled model in which surface water flow and solute transport are described using the zero-inertia equation and the average cross-sectional convection-dispersion equation, respectively, while the two-dimensional Richards equation and the convection-dispersion equation are used to simulate water flow and solute transport in soils, respectively. Solutions are computed numerically using finite differences for surface water flow and finite volumes for solute transports in furrow. Subsurface water flow and solute transport equations are solved using the CHAIN_2D code. An iterative method is used to couple computations of surface and subsurface processes. Both surface and subsurface water flow and solute transport modules are coded in program subroutines and functions in the Intel FORTRAN environment. The coupled model was validated by comparing its simulation results with measured data. Results showed that simulated water front advances in the furrow and water contents in the soil agreed with the observations reasonably well. Good simulations can be achieved with a relatively fine temporal resolution. Numerical oscillations can be eliminated by adopting appropriate time steps. As compared with the traditional furrow irrigation model, the proposed model can better quantify soil water and solute dynamics by considering interactions between surface and subsurface water flow and solute transport processes. The proposed model can be used as a decision tool to design and manage furrow irrigation. [ABSTRACT FROM AUTHOR]

Water shortage and high irrigation rate has increased the need for appropriate irrigation scheduling to improve agricultural water use efficiency for food security in Northwest China. A two-year field experiment was carried out to investigate the response of melon ( Cucumis melo L.) yield, quality and water productivity (WP) to various soil moisture levels with controlled furrow irrigation in the arid oasis region of Gansu Province. Soil water content (SWC) with values of 55% and 65% FC (field capacity) during blooming to fruit setting stage, and 45%, 55%, and 65% FC during fruit swelling stage, respectively, was considered as the lower limit for irrigation. Considering the fruit marketable yield, WP, and quality, an overall integrated index was developed and then used as an indicator to assess the appropriate irrigation scheduling. The overall integrated index value was computed by using the catastrophe progression method. Results showed that the melon yield (total, marketable and high quality yields), and vitamin C content were highly sensitive to lower SWC limits with value from 45% to 65% FC during fruit swelling stage. The treatment with lower SWC limit of 55% FC during blooming to fruit setting or fruit swelling stage was found without significant effect on melon yield and WP, and the treatment with lower SWC limit of 55% FC from blooming to swelling stage had negative impact on melon yield and vitamin C. Considering the overall integrated index values, the lower SWC limit of 55% and 65% FC was recommendable for furrow irrigation of melon crops during blooming to fruit setting and fruit swelling stages, respectively, in the arid oasis region of Northwest China. [ABSTRACT FROM AUTHOR]

Winter wheat production in the North China Plain (NCP) relies mainly on irrigation. To assess the effect irrigation management practices on crop production, the HYDRUS-1D model was modified by incorporating the crop growth module adopted from the EPIC model. The modified HYDRUS-1D model was calibrated and validated by using data collected from 2006/2007 and 2007/2008 winter wheat growing seasons in Beijing area. The predicted values for soil water content, soil nitrate concentration, crop growth, yield, and evapotranspiration showed good agreements with the measured values. The calibrated model was then used to evaluate the yield and water use efficiency (WUE) under different hydrologic years. The WUE for different irrigation depth was considered as the criterion for investigating the appropriate irrigation management practices. Results showed that the appropriate irrigation depth per application could be determined as 62.5% of the difference between 20 cmpan evaporation and precipitation for hydrologic years with 75%, 50% and 25% probability of rainfall occurrence, respectively, under the recommended nitrogen application rate in Beijing area. And the corresponding total irrigation amount was 244.7, 213.8 and 192.5 mm. The results of this study provide scientific implications for water management of winter wheat under sprinkler irrigation in the NCP and those areas with similar climatic and cropping practice conditions. [ABSTRACT FROM AUTHOR]

Understanding the agro-hydrological processes and water productivity of canal- and well-irrigated systems is vital for agricultural water management in arid regions. In this study, the Agro-Hydrological & chemical and Crop systems simulator (AHC) was used in a distributed manner to evaluate the agro-hydrological processes and to assess water productivity under the conditions of canal- and well-irrigated systems. With the Heji irrigation system (Heji) located in the arid upper Yellow River basin, Northwest China as the case study area, the AHC was calibrated and validated by the field observation data of 2018 and 2019. Then the model was used in a distributed manner for the entire Heji. Results showed that there were significant differences in the agro-hydrological processes and water productivity between canal- and well-irrigated areas. The spatially averaged actual evapotranspiration was larger in canal-irrigated areas, and the cumulative net bottom water and salt fluxes were mainly downward in well-irrigated areas. The applied water was used more efficiently with higher equivalent water productivity of water applied (EWP IP) in canal-irrigated areas. However, the total water consumption (evapotranspiration) was in higher efficient utilization with higher equivalent water productivity of water consumption (EWP ET) in well-irrigated areas. These findings can provide implications for regional irrigation water management and salinity control in the arid areas. • A GIS-based 1D model was used in canal- and well-irrigated systems. • Water balance in canal-irrigated areas is different from that in well-irrigated areas. • The risk of salt accumulation is more serious in canal-irrigated areas. • Canal- and well-irrigated areas shows differences in water productivity. [ABSTRACT FROM AUTHOR]

Inappropriate irrigation and nitrogen application had caused low water and nitrogen use efficiency and severe NO 3 --N leaching in spring wheat field in the Wuliangshuhai lake watershed (WLSLW) of Northwest China. Thus, aimed at determining the rational irrigation and nitrogen fertilization for spring wheat in this area, field experiments were carried out in the 2019 and 2020 seasons to investigate the effects of irrigation and nitrogen application on soil water and nitrogen status, grain yield, and water and nitrogen use efficiency. Three irrigation levels, i.e., 180, 315, and 450 mm (I3, I2 and I1), and three nitrogen fertilization rates, i.e., 170, 250, and 340 kg N ha−1 (N3, N2 and N1) were respectively considered in the experiments. Results indicated that increasing irrigation depth increased root zone soil available water, and increasing nitrogen application could significantly enhance the available nitrogen content in root zone soils and the soil water utilization amount by wheat. Under the control treatment (I1N1), about 25–32% of the applied nitrogen was leached out of the root zone soils throughout the year. Compared to the control treatment, the I2N2 treatment could reduce NO 3 --N leaching by 32%, and increased the water use efficiency (WUE) and partial factor productivity of nitrogen fertilizer (PFP n) by 33% and 44%, respectively. In addition, the highest yield and net profit of 8078 kg ha−1 and 1.82×104 Chinese Yuan ha−1 was achieved by the I2N2 treatment, respectively, and it was 6% higher than that of the control treatment. Therefore, considering the grain yield, WUE, PFP n , economic benefits and environmental impacts, the strategy of 315 mm irrigation and 250 kg N ha−1 nitrogen application is recommended for spring wheat in the arid agricultural watershed of Northwest China and areas with similar conditions. • Over irrigation does not favor soil water storage while it aggravates NO 3 --N leaching. • Annual NO 3 --N leaching accounts for 25–32% of the total applied N. • Seasonal 315 mm irrigation and 250 kg ha−1 N are recommended for wheat in arid Northwest China. [ABSTRACT FROM AUTHOR]

Mitigating climate change and improving food production are major challenges worldwide. Applications of lignite-based bioorganic products (or lignite-based fertilizer) can improve soil physicochemical properties and crop production in saline-sodic farmland. However, little is known about the effects of lignite bioorganic fertilizer (LBF) on greenhouse gas (GHG) emissions and climate change mitigation. Thus, a two-year field experiment was conducted in saline-sodic farmlands in the upper Yellow River basin, Northwest China. The field experiment comprised six treatments, including a negative control without any organic fertilizer (CK), a positive control amended with sheep manure (FYM), and four treatments amended with 1.5 (LBF1), 3 (LBF2), 4.5 (LBF3), and 7.5 t ha−1 (LBF4) LBF. The results showed that the LBF treatments decreased the emissions of CH 4 and CO 2 while increasing N 2 O emissions when the application rate was over 3 t ha−1. Additionally, FYM treatment acted as a CH 4 source, while LBF2 and LBF3 treatments were both CH 4 sinks. The LBF3 treatment had the highest net ecosystem carbon budget (NECB) and the lowest net ecosystem global warming potential (NGWP), which were 6.04 and 4.82 t ha−1 and -22.09 and −17.39 t ha−1 higher than those of the CK treatment in 2019 and 2020, respectively. Moreover, the net ecosystem economic budget (NEEB) of the LBF2 and LBF3 treatments was higher than that of the other treatments. Compared with the CK treatment, the FYM treatment increased the NCEB and decreased NGWP but it also decreased the NEEB. For nitrogen and carbon cycling, the LBF3 treatment increased almost all gene families involved in nitrogen cycling, except for nirA and hao , while the FYM treatment reduced the nirKS, norBC , nosZ , and hao gene families. The modules for carbohydrate metabolism and methanogenesis were also reduced by the LBF treatments. In conclusion, the LBF2 and LBF3 treatments had higher NECB, NGWP, and NEEB, indicating that the application of lignite bioorganic fertilizer at 3.0–4.5 t ha−1 is appropriate for climate change mitigation in saline-sodic farmlands in the upper Yellow River basin, Northwest China. [ABSTRACT FROM AUTHOR]

Highlights: [•] A 2D dynamic root water uptake model was developed based on Vrugt model. [•] The interaction between root water uptake and crop growth was considered. [•] A new coupled model was developed based on the CHAIN_2D and EPIC. [•] Crop yield and LAI can be simulated by the coupled model. [•] Using the coupled model to investigate appropriate irrigation management practices. [ABSTRACT FROM AUTHOR]

Highlights: [•] We study the impacts of various soil matric potential thresholds (SMP) on tomato crop. [•] Tomato yields, fruit quality and water productivity (WP) were evaluated. [•] Crop coefficients of tomato were determined from crop density and plant height. [•] Mild to moderate water stress may benefit the tomato fruit quality. [•] The recommend SMP threshold for tomato irrigation in the study area is −40kPa [ABSTRACT FROM AUTHOR]

Aiming at investigating an appropriate irrigation management strategy that could lead to increase onions yields and improve water productivity (WP), a two-year field experiment was conducted in the arid region of Northwest China with drip irrigation and plastic mulch. Eight treatments were considered: four with different levels of water stress throughout the crop season, and four where water stress was applied at the establishment, development, bulbification and ripening stages. The seasonal actual evapotranspiration (ET), plant height, above-ground biomass, yield (total, high-quality and marketable quality yields) as well as related irrigation and total water productivity were determined. Plant heights, above-ground biomass and the referred yields have shown to be sensitive to water stress, particularly during the development and bulbification stages. Due to the importance of quality of horticultural products, the WP computed with the yields of high-quality bulbs revealed the most informative contrarily to the WP computed with the total yields. It could be concluded that water stress has to be avoided during the development and bulbification stages, and only small deficits are acceptable if applied throughout the crop season. [ABSTRACT FROM AUTHOR]

Highlights: [•] Changes of soil water, salinity and yield were simulated using SWAP for wheat. [•] SWAP was modified by adopting EPIC crop model and osmotic head-dependent function. [•] Model was well calibrated and validated using experimental data in 2007 and 2008. [•] Fifteen treatments with different irrigation and GWD were predicted and evaluated. [•] A target GWD of 1.0–1.5m was suggested to be optimal for wheat's growth. [Copyright &y& Elsevier]

Summary: Reasonable estimates of groundwater recharge and discharge through evapotranspiration is critical for sustainable water resources management in shallow water table areas. The hydrologic processes are highly interactive between the vadose zone and groundwater under shallow water table conditions. In traditional groundwater flow models, the recharge and evapotranspiration fluxes are often oversimplified as a simple sink/source term. However, the recharge and evapotranspiration are observed to vary with topography, soil type, land use, and water management practices. Additionally, they are known to vary temporally and spatially and are difficult to estimate, especially in arid and semi-arid regions. Thus, it is important to devise an appropriate method to estimate the recharge and evapotranspiration fluxes in groundwater modeling. In this study, a Soil–Water–Atmosphere–Plant (SWAP) package was integrated into a groundwater flow model (MODFLOW) in such a way that the SWAP package calculates vertical flux for MODFLOW, while MODFLOW provides averaged water table depth to determine the bottom boundary condition for SWAP zones. The SWAP zones in MODFLOW are derived from a combination of topology, soil type, land use, water management practices using geographic information systems (GIS). Then the MODFLOW with SWAP package was tested using a two-dimensional saturated–unsaturated water table recharge experiment. Results showed that the simulated water table elevations matched well with the observed ones except at the early period during which they were slightly higher than the observed ones, probably due to neglecting lateral diffusion in the unsaturated zone. Finally, we applied MODFLOW with SWAP package to simulate a regional groundwater flow problem in Hetao Irrigation District, upper Yellow River basin of North China. The simulation results validated the applicability of the developed MODFLOW with SWAP package for practical regional groundwater modeling. [ABSTRACT FROM AUTHOR]

Abstract: The effect of aquifer heterogeneity on flow and solute transport in two-dimensional isotropic porous media was analyzed using the Monte Carlo method. The two-dimensional logarithmic permeability (ln K) was assumed to be a non-stationary random field with its increments being a truncated fractional Lévy motion (fLm). The permeability fields were generated using the modified successive random additions (SRA) algorithm code SRA3DC [http://www.iamg.org/CGEditor/index.htm]. The velocity and concentration fields were computed respectively for two-dimensional flow and transport with a pulse input using the finite difference codes of MODFLOW 2000 and MT3DMS. Two fLm control parameters, namely the width parameter (C) and the Lévy index (α), were varied systematically to examine their effect on the resulting permeability, flow velocity and concentration fields. We also computed the first- and second-spatial moments, the dilution index, as well as the breakthrough curves at different control planes with the corresponding concentration fields. In addition, the derived breakthrough curves were fitted using the continuous time random walk (CTRW) and the traditional advection-dispersion equation (ADE). Results indicated that larger C and smaller α both led to more heterogeneous permeability and velocity fields. The Lévy-stable distribution of increments in ln K resulted in a Lévy-stable distribution of increments in logarithm of the velocity (ln v). Both larger C and smaller α created sharper leading edges and wider tailing edges of solute plumes. Furthermore, a relatively larger amount of solute still remained in the domain after a relatively longer time transport for smaller α values. The dilution indices were smaller than unity and increased as C increased and α decreased. The solute plume and its second-spatial moments increased as C increased and α decreased, while the first-spatial moments of the solute plume were independent of C and α values. The longitudinal macrodispersivity was scale-dependent and increased as a power law function of time. Increasing C and decreasing α both resulted in an increase in longitudinal macrodispersivity. The transport in such highly heterogeneous media was slightly non-Gaussian with its derived breakthrough curves being slightly better fitted by the CTRW than the ADE, especially in the early arrivals and late-time tails. [Copyright &y& Elsevier]

We have investigated non-Darcian flow to a vertical fracture represented as an extended well using a linearization procedure and a finite difference method in this study. Approximate analytical solutions have been obtained with and without the consideration of fracture storage based on the linearization procedure. A numerical solution for such a non-Darcian flow case has also been obtained with a finite difference method. We have compared the numerical solution with the approximate analytical solutions obtained by the linearization method and the Boltzmann transform. The results indicate that the linearized solution agrees generally well with the numerical solution at late times, and underestimates the dimensionless drawdown at early times, no matter if the fracture storage is considered or not. When the fracture storage is excluded, the Boltzmann transform solution overestimates the dimensionless drawdown during the entire pumping period. The dimensionless drawdowns in the fracture with fracture storage for different values of dimensionless non-Darcian hydraulic conductivity β approach the same asymptotic value at early times. A larger β value results in a smaller dimensionless drawdown in both the fracture and the aquifer when the fracture storage is included. The dimensionless drawdown is approximately proportional to the square root of the dimensionless time at late times. [ABSTRACT FROM AUTHOR]

Abstract: Water resources allocated to the agricultural sector in the Yellow River basin are being reduced due to severe water scarcity and increased demand by the non-agricultural sectors. In large-scale irrigation districts, the application of water-saving practices, e.g., improving the canal system, using water-saving irrigation technology and adjusting cropping patterns, is required for the sustainable agricultural development and the river basin environmental equilibrium. Adopting water-saving practices leads to lowering the groundwater table and to controlling salinity impacts related to excessive irrigation. However, assessing the effects of water-saving practices on the groundwater system requires further investigation. The Jiefangzha Irrigation Scheme of the Hetao Irrigation District is used as a case study for analyzing the temporal and spatial dynamics of the groundwater table. A lumped parameter groundwater balance model has been developed with this purpose and to assess impacts of various water-saving practices. The model was calibrated with monthly datasets relative to the non-frozen periods of 1997–1999 and validated with datasets from 2000 to 2002. Results indicate that canal seepage and deep percolation account for respectively 48% and 44% of the annual groundwater recharge. Groundwater discharge by direct evaporation and plant roots uptake represents 82% of the total annual groundwater discharge. After validation, the model was applied to assess the impacts of various canal and farm irrigation water-saving practices. It was observed that improvements in the canal system (e.g., canal lining, upgrading the hydraulic regulation and control structures, improving delivery schedules) might lower the groundwater table by 0.28–0.48m, depending upon the level of implementation of these measures. Higher declines of the groundwater table are predicted when water-saving technologies are applied at both the canal and the farm systems. That decline of the water table favours salinity control and reduces capillary rise, thus reducing the groundwater evaporation and uptake by plant roots; that reduction may attain 128mm. However, predictions may change depending on the way how water-saving measures are applied, which may be different of assumptions made; therefore, there is the need to perform a follow-up of the interventions in order to update predictions. Results indicate the need for appropriate research leading to improved irrigation management when the decline of the groundwater level will reduce groundwater contribution to vegetation growth. [Copyright &y& Elsevier]

Abstract: Biodiesel has received much attention in recent years. Although numerous reports are available on the production of biodiesel from vegetable oils of terraneous oil-plants, such as soybean, sunflower and palm oils, the production of biodiesel from microalgae is a newly emerging field. Microalgal biotechnology appears to possess high potential for biodiesel production because a significant increase in lipid content of microalgae is now possible through heterotrophic cultivation and genetic engineering approaches. This paper provides an overview of the technologies in the production of biodiesel from microalgae, including the various modes of cultivation for the production of oil-rich microalgal biomass, as well as the subsequent downstream processing for biodiesel production. The advances and prospects of using microalgal biotechnology for biodiesel production are discussed. [Copyright &y& Elsevier]

Low quality water has been widely used for irrigation all over the world due to water shortage. However, the use of low quality water may cause accumulation of salt in root-zone soils, resulting in poor nitrogen utilization by crops. The objective of the present study was to investigate the effects of sodium chloride (NaCI) on mineralization and nitrification of soils in the North China Plain (NCP). The experiments were conducted with laboratory incubators at 30CC. Five levels of NaCl-salt concentrations 0%, 2%, 3%, 5% and 8% in the added solutions were used in the soil samples collected from NCP. The mineralization at NaCl-salt concentration lower than 3% was not significantly different from that of the control, whereas, significant inhibition of mineralization was found in the treatments with NaCI-salt concentration higher than 3%. The inhibition of mineralization was attributed to the retardation of nitrification in relatively high salt content because ammonification was not depressed by the added NaC1 salt. The gas losses and nitrification were found decreasing with the increase in salinity. It was also found that the nitrification was more sensitive to salinity than the mineralization. Nitrification of soil samples was inhibited by 44.72%, 57.87%, and 83.64% compared with the control after 38 days of incubation at NaCI-salt concentrations of 3%, 5% and 8%, respectively. The time dependence of both the mineralization and nitrification can be fitted into a first-order kinetic model. The rate constant of mineralization and nitrification decreased exponentially with the salt content in the soils. The results of the present research may provide some scientific implications for the use of saline water or treated sewage water in the farming regions of the NCP. [ABSTRACT FROM AUTHOR]

Abstract: A laboratory experiment was carried out to study the emitter performance of three commonly used emitter types with the application of freshwater and treated sewage effluent (TSE). The three emitter types are the inline-labyrinth types of emitters with a turbulent flow (E1) and a laminar flow (E2) and the online pressure-compensation type of emitters (E3). The qualities of freshwater and TSE were measured, and the emitter performance was evaluated, using the relative emitter discharge, the reduction of emitter discharge (q reduction), the coefficient of variation of emitter discharge (CV), the emission uniformity (EU), Christiansen uniformity coefficient (CU), and the percentage of emitter clogging (P clog). Results showed that all indices were affected by water quality, emitter type and time of operation. The values of q reduction, CV and P clog for the TSE treatments were greater than those for the freshwater treatments. The values of EU and CU for the TSE treatment were lower than those for the freshwater treatments. The q reduction, CV and P clog increased and the EU and CU decreased as operational time increasing for the TSE treatment. For both freshwater and TSE treatments, the emitter clogging was more severe, the CV was greater, and the EU and CU were smaller for emitter type E2 than those for emitter types E1 and E3. Thus a more severe clogging was found for emitter type E2 due to its smaller flow-path dimension and higher manufacturing coefficient of variation in addition to the high pH values and relatively high total dissolved solids (TDS) values of the used water. Analyses of water quality and the precipitation components inside and at the outlet of emitters revealed that chemical precipitation was the main reason for emitter clogging due to high pH and ions’ concentration, especially in the TSE. Flushing emitters and drip pipes did not efficiently alleviate emitter clogging caused by chemical precipitation. In a conclusion, emitter type E3 showed a better anti-clogging function than emitter types E1 and E2 and was recommended for irrigation with TSE in the Beijing area of China. [Copyright &y& Elsevier]

Summary: In this study, we have obtained numerical solutions for non-Darcian flow to a well with the finite difference method on the basis of the Izbash equation, which states that the hydraulic gradient is a power function of the specific discharge. The comparisons between the numerical solutions and the Boltzmann solutions and linearization solutions have also been done in this study. The results indicated that the linearization solutions for both the infinitesimal-diameter well and the finite-diameter well agree very well with the numerical solution at late times, while the linearization method underestimates the dimensionless drawdown at early and moderate times. The Boltzmann method works well as an approximate analytical solution for the infinitesimal-diameter well. Significant differences have been found between the Boltzmann solution for a finite-diameter well and the numerical solution during the entire pumping period. The analysis of the numerical solution implies that all the type curves inside the well for different dimensionless non-Darcian conductivity kD values approach the same asymptotic value at early times, while a larger kD leads to a smaller drawdown inside the well at late times. A larger kD results in a larger drawdown in the aquifer at early times and a smaller drawdown in the aquifer at late times. Flow approaches steady-state earlier when kD is larger. [Copyright &y& Elsevier]

Abstract: In this study, we use a linearization procedure and a finite difference method to solve non-Darcian flow to a well in an aquifer–aquitard system. The leakage effect is considered. Flow in the aquifer is assumed to be non-Darcian and horizontal, whereas flow in the aquitard is assumed to be Darcian and vertical. The Izbash equation [Izbash SV. O filtracii V Kropnozernstom Materiale. USSR: Leningrad; 1931 [in Russian]] is employed to describe the non-Darcian flow. The wellbore storage is also considered in this study. An approximate semi-analytical solution has been obtained by the linearization procedure, and a numerical solution has been obtained by using a finite difference method. The previous solutions for Darcian flow case and non-Darcian flow case without leakage can be described as special cases of the new solutions. The error caused by the linearization procedure has also been analyzed. The relative error caused by the linearization procedure is nearly 100% at early times, and decreases to zero at late times. We have also compared the results in this study with Wen et al. [Wen Z, Huang G, Zhan H. A numerical solution for non-Darcian flow to a well in a confined aquifer using the power law function. J Hydrol, 2008d [in revision]] in which the leakage effect is not considered, and Hantush and Jacob [Hantush MS, Jacob CE. Non-steady radial flow in an infinite leaky aquifer. Trans Am Geophys Union 1955;36(1):95–100] who investigated a similar problem in Darcian flow case. The comparison of this study and Wen et al. (2008d) indicates the dimensionless drawdown in the aquifer with leakage is less than that without leakage, and the leakage has little effect at early times. The comparison between the results of this study and that of Hantush and Jacob (1955) indicates that the dimensionless drawdown in the aquifer for non-Darcian flow is larger at early times and smaller at late times, than their counterparts for Darcian flow. A larger dimensionless non-Darcian conductivity k D results in a smaller dimensionless drawdown in the aquifer at late times, and leads to a larger dimensionless drawdown in the aquifer at early times. A smaller dimensionless leakage parameter B D results in a smaller drawdown at late times, and the leakage does not affect the early-time drawdown. The analysis of the dimensionless drawdown inside the well has also been included in this study when the wellbore storage is considered. [Copyright &y& Elsevier]

Abstract: The fractional advection–dispersion equation (FADE) known as its non-local dispersion, has been proven to be a promising tool to simulate anomalous solute transport in groundwater. We present an unconditionally stable finite element (FEM) approach to solve the one-dimensional FADE based on the Caputo definition of the fractional derivative with considering its singularity at the boundaries. The stability and accuracy of the FEM solution is verified against the analytical solution, and the sensitivity of the FEM solution to the fractional order α and the skewness parameter β is analyzed. We find that the proposed numerical approach converge to the numerical solution of the advection–dispersion equation (ADE) as the fractional order α equals 2. The problem caused by using the first- or third-kind boundary with an integral-order derivative at the inlet is remedied by using the third-kind boundary with a fractional-order derivative there. The problems for concentration estimation at boundaries caused by the singularity of the fractional derivative can be solved by using the concept of transition probability conservation. The FEM solution of this study has smaller numerical dispersion than that of the FD solution by Meerschaert and Tadjeran (J Comput Appl Math 2004). For a given α, the spatial distribution of concentration exhibits a symmetric non-Fickian behavior when β =0. The spatial distribution of concentration shows a Fickian behavior on the left-hand side of the spatial domain and a notable non-Fickian behavior on the right-hand side of the spatial domain when β =1, whereas when β =−1 the spatial distribution of concentration is the opposite of that of β =1. Finally, the numerical approach is applied to simulate the atrazine transport in a saturated soil column and the results indicat that the FEM solution of the FADE could better simulate the atrazine transport process than that of the ADE, especially at the tail of the breakthrough curves. [Copyright &y& Elsevier]

Abstract: Irrigation and fertilization management practices play important roles in crop production. In this paper, the Root Zone Water Quality Model (RZWQM) was used to evaluate the irrigation and fertilization management practices for a winter wheat–summer corn double cropping system in Beijing, China under the irrigation with treated sewage water (TSW). A carefully designed experiment was carried out at an experimental station in Beijing area from 2001 to 2003 with four irrigation treatments. The hydrologic, nitrogen and crop growth components of RZWQM were calibrated by using the dataset of one treatment. The datasets of other three treatments were used to validate the model performance. Most predicted soil water contents were within ±1 standard deviation (S.D.) of the measured data. The relative errors (RE) of grain yield predictions were within the range of −26.8% to 18.5%, whereas the REs of biomass predictions were between −38% and 14%. The grain nitrogen (N) uptake and biomass N uptake were predicted with the RE values ranging from −13.9% to 14.7%, and from −11.1% to 29.8%, respectively. These results showed that the model was able to simulate the double cropping system variables under different irrigation and fertilization conditions with reasonable accuracy. Application of RZWQM in the growing season of 2001–2002 indicated that the best irrigation management practice was no irrigation for summer corn, three 83mm irrigations each for pre-sowing, jointing and heading stages of winter wheat, respectively. And the best nitrogen application management practice was 120kgNha−1 for summer corn and 110kgNha−1 for winter wheat, respectively, under the irrigation with TSW. We also obtained the alternative irrigation management practices for the hydrologic years of 75%, 50% and 25%, respectively, in Beijing area under the conditions of irrigation with TSW and the optimal nitrogen application. [Copyright &y& Elsevier]

Abstract: We have derived an analytical solution for two-region flow toward a well in a confined aquifer based on a linearization method. The two-region flow includes Izbash non-Darcian flow near the well and Darcian flow in the rest of the aquifer. The wellbore storage is also considered. The type curves in the non-Darcian and Darcian flow domains are obtained by a numerical Laplace inversion method incorporated in MATLAB programs. We have compared our results with the one-region Darcian flow model (Theis). Our solutions agree with those of Sen [Sen Z. Type curves for two-region well flow. J Hydr Eng 1988;114(12):1461–84] which were obtained using the Boltzmann transform at late times for fully turbulent flow, while some difference has been found at early and moderate times. We have defined a dimensionless non-Darcian hydraulic conductivity term which is shown to be a key parameter for analyzing the two-region flow. A smaller dimensionless non-Darcian hydraulic conductivity results in a larger drawdown in the non-Darcian flow region at late times. However, the dimensionless non-Darcian hydraulic conductivity does not affect the slope of the dimensionless drawdown versus the logarithmic dimensionless time in the non-Darcian flow region at late times. The dimensionless non-Darcian hydraulic conductivity does not affect the late time drawdown in the Darcian flow region. [Copyright &y& Elsevier]

Abstract: We have developed a new method to analyze the power law based non-Darcian flow toward a well in a confined aquifer with and without wellbore storage. This method is based on a combination of the linearization approximation of the non-Darcian flow equation and the Laplace transform. Analytical solutions of steady-state and late time drawdowns are obtained. Semi-analytical solutions of the drawdowns at any distance and time are computed by using the Stehfest numerical inverse Laplace transform. The results of this study agree perfectly with previous Theis solution for an infinitesimal well and with the Papadopulos and Cooper’s solution for a finite-diameter well under the special case of Darcian flow. The Boltzmann transform, which is commonly employed for solving non-Darcian flow problems before, is problematic for studying radial non-Darcian flow. Comparison of drawdowns obtained by our proposed method and the Boltzmann transform method suggests that the Boltzmann transform method differs from the linearization method at early and moderate times, and it yields similar results as the linearization method at late times. If the power index n and the quasi hydraulic conductivity k get larger, drawdowns at late times will become less, regardless of the wellbore storage. When n is larger, flow approaches steady state earlier. The drawdown at steady state is approximately proportional to r 1−n , where r is the radial distance from the pumping well. The late time drawdown is a superposition of the steady-state solution and a negative time-dependent term that is proportional to t (1−n)/(3−n), where t is the time. [Copyright &y& Elsevier]

Summary: Non-Darcian flow towards a well which fully penetrates a confined single vertical fracture is presented in this paper on the basis of the Izbash equation. We have obtained semi-analytical solutions for non-Darcian flow by using the Boltzmann transform and developed the non-Darcian flow well functions for cases with and without the effect of wellbore storage. The results show that the non-Darcian flow type curves are more or less deviated from the Darcian flow type curve. The non-linear effect is mainly attributable to the turbulent factor, v, a dimensionless parameter related to the pumping rate, the fracture aperture, the fracture thickness, and two constants k′ and n used in the Izbash power-law. The non-linear effect appears to be less sensitive to the power-law index, n. When excluding wellbore storage, the well function at early times is proportional to v −1/(n−1) u −n/(n−1), where u is a dimensionless term inversely proportional to time; whereas the well function at late times is approximated as , where A 0(n) is a finite term depending on n. When considering wellbore storage, drawdowns inside the well with different v values approach the same asymptotic value at small times, and the effect of wellbore storage is only found at the early stage of pumping. [Copyright &y& Elsevier]

Abstract: In this paper, we used the continuous time random walk (CTRW) framework to characterize the transport process in 1250-cm long one-dimensional homogenous and heterogeneous soil columns at the experiments conducted by Huang et al. [Huang, K., Toride, N., van Genuchten, M.Th., 1995. Experimental investigation of solute transport in large, homogeneous and heterogeneous, saturated soil columns. Trans. Porous Media. 18, 283–302]. The transport process was also simulated by using the advection–dispersion equation (ADE) and the spatial fractional advection–dispersion equation (FADE) for comparison. In the homogeneous soil column, the non-Fickian behavior is found at the distances less than 1000cm with β values larger than 1.60, but less than 2, and Fickian form transport is obtained at distances larger than 1000cm with β values larger than 2. In the heterogeneous soil column, we found the most anomalous behavior at distances from 200cm to 700cm with β values ranging from 0.894 to 0.958, and non-Fickian transport process is observed at distances larger than 800cm with β values in the range between 1 and 1.3. More significant non-Fickian behavior is found for transport in the heterogeneous soil column than that in the homogeneous soil column. The CTRW fits to the breakthrough curves (BTCs) have lower values of root mean square error (RMSE) and higher values of determination coefficient (r 2), with respect to the fits of ADE and FADE. The CTRW model also is better captures the full evolution of BTCs, and especially their tails. [Copyright &y& Elsevier]

Abstract: A semi-analytical inverse method and the corresponding program FADEMain for parameter estimation of the fractional advection–dispersion equation (FADE) were developed in this paper. We have analyzed Huang et al.''s [Huang, K., Toride, N., van Genuchten, M.Th., 1995. Experimental investigation of solute transport in large homogeneous and heterogeneous saturated soil columns. Trans. Porous Media 18, 283–302.] laboratory experimental data of conservative solute transport in 12.5-m long homogeneous and heterogeneous soil columns to test the non-Fickian dispersion theory of FADE. The dispersion coefficient was calculated by fitting the analytical solution of FADE to the measured data at different transport scales. We found that the dispersion coefficient increased exponentially with transport scale for the homogeneous column, whereas it increased with transport scale in a power law function for the heterogeneous column. The scale effect of the dispersion coefficient in the heterogeneous soil was much more significant comparing to that in the homogeneous soil. The increasing rate of dispersion coefficient versus transport distance was smaller for FADE than that for the advection–dispersion equation (ADE). Finite difference numerical approximations of the scale-dependent FADE were established to interpret the experimental results. The numerical solutions were found to be adequate for predicting scale-dependent transport in the homogeneous column, while the prediction for the heterogeneous column was less satisfactory. [Copyright &y& Elsevier]

Abstract: Empirical models have been developed to describe the soil water retention curve (SWRC). Applications of the fractal theory may provide a useful tool to fill the gap between the use of empirical models and physical interpretation of their parameters. Especially a more generalized model for the SWRC has been developed based on the pore–solid fractal (PSF) distribution. The PSF model covers several existing models as its special cases and theoretically provides a direct way to estimate the SWRC fractal dimension from particle size distributions (PSDs). The first objective of this study was to evaluate the SWRC with the PSF distribution using more than 400 data sets of PSD and SWRC. The second objective was to establish a relationship between the fractal dimension and soil texture. Analyses of the data sets showed that the fractal dimension values estimated using the PSD data were consistently smaller than those estimated using the SWRC data. Therefore, using the fractal dimension from PSD to predict the SWRC will result in underestimation. To resolve the problem, the soil data sets of PSD and SWRC were used to establish relationships between the fractal dimensions in the PSF model of SWRC and soil clay content as well as soil texture class. Independent SWRC data sets were used to test the methods. Predicted results using the PSF model of SWRC with the fractal dimension estimated using clay content or soil texture class were compared with the measured soil water retention data. Linear regressions of the predicted and measured SWRC showed good agreement for relatively fine texture soils with the coefficients of determination (r 2) of 0.940. [Copyright &y& Elsevier]

• Four data assimilation methods are compared to estimate time-varying parameters. • Parameter correction method is not sensitive to parameter update order. • Partitioned update parameter correction method has higher assimilation stability. The hydraulic properties of the soil top layer may change during the growth period due to various factors such as wetting and drying cycles, tillage practices, and crop root growth. In this study, the potential of the assimilation method to estimate time-varying soil hydraulic parameters is explored. Four assimilation schemes, including the simultaneous update state augmentation method, the partitioned update state augmentation method, the simultaneous update parameter correction method, and the partitioned update parameter correction method, are compared. The performance of four assimilation schemes on parameter estimations and soil moisture simulations is tested first using the synthetic case. The influence of initial parameter values and a parameter update order on assimilation is also analyzed. Finally, the partitioned update parameter correction method is applied to a real case involving a field drip irrigation experiment. The results show that when the analyzed parameter has either a periodical or a linear variation, there is a time lag between the assimilation value and the true value. The assimilation method can respond immediately to an abrupt change of the parameter value. Using the simultaneous update method leads to an obvious parameter correlation problem. In contrast, the partitioned update method can relieve the parameter correlation problems, thereby improving the accuracy of parameter estimations and pressure head simulations. However, when the initial values of the parameters deviate from their true values to a certain extent, the partitioned update method cannot obtain accurate parameter estimations. Compared with the partitioned update state augmentation method, the partitioned update parameter correction method is not sensitive to the parameter update order. The partitioned update parameter correction method has higher computational efficiency and assimilation stability, and it can obtain more accurate parameter estimations and soil moisture predictions in comparison with the traditional state augmentation method. The partitioned update parameter correction method provides an assimilation tool for improving the predictions of soil moisture by considering the time-varying parameters. [ABSTRACT FROM AUTHOR]

Many approaches have been developed to analyze remote sensing images. However, for the classification of large-scale problems, most algorithms showed low computational efficiency and low accuracy. In this paper, the newly developed semi-supervised extreme learning machine (SS-ELM) framework with k-means clustering algorithm for image segmentation and co-training algorithm to enlarge the sample sets was used to classify the agricultural planting structure at large-scale areas. Data sets collected from a small-scale area within the Hetao Irrigation District (HID) at the upper reaches of the Yellow River basin were used to evaluate the SS-ELM framework. The results of the SS-ELM algorithm were compared with those of the random forest (RF), ELM, support vector machine (SVM) and semi-supervised support vector machine (S-SVM) algorithms. Then the SS-ELM algorithm was applied to analyze the complex planting structure of HID in 1986–2010 by comparing the remote sensing estimated results with the statistical data. In the small-scale case, the SS-ELM algorithm performed better than the RF, ELM, SVM, and S-SVM algorithms. For the SS-ELM algorithm, the average overall accuracy (OA) was in a range of 83.00–92.17%. On the contrary, for the other four algorithms, their average OA values ranged from 56.97% to 92.84%. Whereas, in the classification of planting structure in HID, the SS-ELM algorithm had an excellent performance in classification accuracy and computational efficiency for three major planting crops including maize, wheat, and sunflowers. The estimated areas by using the SS-ELM algorithm based on the remote sensing images were consistent with the statistical data, and their difference was within a range of 3–25%. This implied that the SS-ELM framework could be served as an effective method for the classification of complex planting structures with relatively fast training, good generalization, universal approximation capability, and reasonable learning accuracy. [ABSTRACT FROM AUTHOR]

• A Gaussian Process based Iterative Ensemble Kalman Filter (GPIEnKF) is proposed. • Parameter estimations are influenced by layout and number of observation points. • Computational efficiency of GPIEnKF is higher than original ensemble Kalman filter. Water flow in the unsaturated zone is an important component of the water cycle. Accurate estimation of soil hydraulic parameters ensures precise simulations of water flow in the unsaturated zone. In this study, a Gaussian Process-based Iterative Ensemble Kalman Filter method (GPIEnKF) is proposed and applied for estimating soil hydraulic parameters for two-dimensional soil water flow. The method involves a surrogate model for two-dimensional soil water flow that is based on the Gaussian Process method. The accuracy and efficiency of the GPIEnKF method are validated using two synthetic cases and a real dataset involving a field experiment with drip irrigation. The impact of the layout of observation points as well as the number of training base points and observation points on the estimation of parameters are also analyzed. The results show that the surrogate model can accurately predict pressure heads at observation points. The layout of observation points that precisely describes infiltration water movement allows the surrogate model to better emulate the original model, thereby improving the accuracy of parameter estimation. The number of training base points is found to have only a small influence on parameter estimation. The accuracy of parameter estimation and pressure head predictions can be further improved by increasing the number of observation points. However, the accuracy of predictions is affected by the uncertainty of boundary conditions and the soil spatial heterogeneity. The GPIEnKF method can effectively estimate multiple parameters characterizing water flow in layered soils. As compared with the standard Iterative Ensemble Kalman Filter, the GPIEnKF method can greatly improve computational efficiency while obtaining comparable results. The GPIEnKF method is an efficient tool for parameter estimation of multi-dimensional soil water flow. [ABSTRACT FROM AUTHOR]

As the size and service requirements of today's networks gradually increase, large numbers of proprietary devices are deployed, which leads to network complexity, information security crises and makes network service and service provider management increasingly difficult. Network function virtualization (NFV) technology is one solution to this problem. NFV separates network functions from hardware and deploys them as software on a common server. NFV can be used to improve service flexibility and isolate the services provided for each user, thus guaranteeing the security of user data. Therefore, the use of NFV technology includes many problems worth studying. For example, when there is a free choice of network path, one problem is how to choose a service function chain (SFC) that both meets the requirements and offers the service provider maximum profit. Most existing solutions are heuristic algorithms with high time efficiency, or integer linear programming (ILP) algorithms with high accuracy. It's necessary to design an algorithm that symmetrically considers both time efficiency and accuracy. In this paper, we propose the Q-learning Framework Hybrid Module algorithm (QLFHM), which includes reinforcement learning to solve this SFC deployment problem in dynamic networks. The reinforcement learning module in QLFHM is responsible for the output of alternative paths, while the load balancing module in QLFHM is responsible for picking the optimal solution from them. The results of a comparison simulation experiment on a dynamic network topology show that the proposed algorithm can output the approximate optimal solution in a relatively short time while also considering the network load balance. Thus, it achieves the goal of maximizing the benefit to the service provider. [ABSTRACT FROM AUTHOR]

This research paper investigates the firm-value effects of the carbon management practices. Moreover, it also aims to respond to the recent calls, so as to investigate the firm value relevance of the carbon management practices. The findings from this study contribute to the literature that is based on the corporate responses to climate change initiatives. Centered on a sample of S&P 500 firms, from the year 2011–2018 (1780 firm-year observations), this study finds that carbon management practices (e.g. carbon reduction targets, external carbon assurance and carbon communication) are positively associated with the market value of equity, or in other words, the market capitalization. Empirical results from the study show that the external carbon assurance contributes an amount of 10% to the market value of the firms, as compared to an amount of 5% and 4% for the carbon targets and the carbon communication, respectively. These findings may assist managers in making informed estimations and judgement regarding the costs and benefit analysis of each of the carbon management practices. Overall, our results are robust enough to alternate the proxies for the firm performance and endogeneities. [ABSTRACT FROM AUTHOR]

In order to help financial users to invest, and to provide users with comprehensive and accurate information about financial securities, information about financial securities from multi-heterogeneous information is obtained. The characteristics of financial information are analyzed to provide valuable investment advice to users. According to the financial characteristics of the user's interest, the characteristics of the investor's interest are extracted from the heterogeneous information. Then, the multi-level model is proposed to analyze the characteristics. Through the multi-level model, the conversion of convertible bonds and the net value of closed funds are predicted. In the first level, based on the characteristics of convertible bonds and closed funds, three models of trend evaluation model, SVR (Support Vector Regression) model and neural network backpropagation network (BPN) model are used to predict financial characteristics. In the second level, the results produced by the three models in the first level are fused by the neural network. The third level optimizes the neural network based on the second level. The optimal initial weights and thresholds are selected by genetic algorithm to obtain better prediction results. The results show that the model can predict the characteristics of convertible bonds and closed funds more accurately. Therefore, the model provides a certain reference for financial users' investment. [ABSTRACT FROM AUTHOR]

Barium strontium titanate (Ba1‐xSrxTiO3‐BST) ceramics, where x = 0.05, 0.15, 0.25, and 0.35, was prepared via a solid‐state reaction method. The lattice structures and morphologies of the ceramic samples were analyzed using X‐ray diffraction and scanning electron microscopy technologies. The dielectric and ferroelectric properties of the BST ceramics were characterized using a precision impedance analyzer and a ferroelectric polarization‐electric field (P‐E) hysteresis loop tester, respectively. The electrocaloric effect was indirectly calculated using the Maxwell relations and P‐E loops as a function of temperature and electrical field, and also directly measured using a computer‐controlled thermocouple and high‐voltage power supply. An adiabatic temperature change of 1.82 K was procured, indicating a promising potential in the applications as cooling devices. [ABSTRACT FROM AUTHOR]

Background and aims: Inappropriate irrigation and nitrogen fertilization caused high global warming potential (GWP) while reduced carbon sequestration of farmland systems in arid regions. Understanding the effects of irrigation and nitrogen fertilization on net ecosystem carbon budget (NECB) and its components are crucial to mitigate GWP and increase carbon sequestration. Methods: A field experiment was carried out to investigate the impact of irrigation and nitrogen fertilization on soil greenhouse gas (GHG) emissions, crop net primary productivity (NPP), NECB and net GWP from spring wheat farmland in arid Northwest China. Three irrigation depth levels, 180, 315, and 450 mm and three nitrogen fertilization levels, 170, 250, and 340 kg ha–1 were designed. Results: Irrigation and fertilization significantly affected GHG emissions and carbon sequestration of farmland system. Reducing irrigation depth from 450 to 315 mm reduced soil CO2 and N2O emissions but did not significantly reduce NPP. Increasing nitrogen fertilization from 170 kg ha–1 to 250 kg ha–1 improved NPP, but continuously increasing nitrogen input decreased NPP while increasing soil CO2 and N2O emissions. Therefore, the NECB first increased and then decreased, while the net GWP first decreased and then increased as the irrigation depth and nitrogen fertilization decreased. Overall, the moderate irrigation and fertilization treatment (i.e., 315 mm irrigation and 250 kg ha–1 nitrogen fertilization) obtained the highest NECB and the lowest net GWP. Conclusion: Improving irrigation and fertilization management can increase carbon sequestration and mitigate the net GWP of farmland systems by increasing crop NPP and reducing soil GHG emissions. [ABSTRACT FROM AUTHOR]

Processing tomatoes are major cash crops in the Hetao Irrigation District, Inner Mongolia, China. Conventional irrigation practices have resulted in ecological and environmental problems due to the specific climate and groundwater conditions. Field experiments were conducted to investigate the effects of water stress on processing tomatoes yield, quality, and water use efficiency with plastic mulched drip irrigation in sandy soil of the Hetao Irrigation District. Tomatoes were irrigated at 40%, 60%, 70%, 80% and 100% of crop evapotranspiration (ET c ). Results showed that soil water content and salt concentration mainly varied in the upper 60 cm soil layer. Dry aboveground biomass and yield increased with increased ET c to 80 or 100%. The highest yield was obtained with 80% ET c treatment both years (70 and 81 t/ha). Increasing water stress led to the increase of soluble solids content and Vitamin C. Actual evapotranspiration (ET a ) ranged from 188 to 323 mm in the two seasons, and increased quadratically when the irrigation depth increased to 80% ET c . The highest water use efficiency (WUE) was found at 60% ET c treatment in 2013 and 80% ET c treatment in 2014. Comprehensive analysis of yield, WUE and ET a , irrigated at 80% ET c was recommended as the optimal irrigation strategy in the sandy soil of the Hetao Irrigation District. [ABSTRACT FROM AUTHOR]

In this study, the authors report a novel class of super tough nanocomposite hydrogels with physically dual-crosslinking effects (DC hydrogels) through introducing strong ionic coordination interactions. Herein, graphene oxide (GO) nanosheets and iron (Fe3+) ions act as physical cross-linkers. GO nanosheets trigger the formation of the first cross-linking points through hydrogen bonding with poly(acrylamide -co-acrylic acid) (p(AAm -co-AAc)) chains, while the second cross-linking points are formed by strong ionic coordination interactions between Fe3+ ions and COO− groups of p(AAm -co-AAc) chains. The optimal tough DC hydrogel displays superstretchability (≈20.8 times), remarkable tensile strength (≈3.7 MPa), high toughness (≈48.71 MJ m−3), good self-recovery property (≈84.1% toughness recovery within 4 h without any external stimuli) and fatigue resistance. In summary, this study opens up a new avenue to design and fabricate highly tough hydrogels with outstanding comprehensive properties by the synergistic effects of nanocomposite and dual-crosslinked hydrogels. [ABSTRACT FROM AUTHOR]

Efficient parameter identification is an important issue for mechanistic agro-hydrological models with a complex and nonlinear property. In this study, we presented an efficient global methodology of sensitivity analysis and parameter estimation for a physically-based agro-hydrological model (SWAP-EPIC). The LH-OAT based module and the modified-MGA based module were developed for parameter sensitivity analysis and inverse estimation, respectively. In addition, a new solute transport module with numerically stable schemes was developed for ensuring stability of SWAP-EPIC. This global method was tested and validated with a two-year dataset in a wheat growing field. Fourteen parameters out of the forty-nine total input parameters were identified as the sensitive parameters. These parameters were first inversely calibrated by using a numerical case, and then the inverse calibration was performed for the real field experimental case. Our research indicates that the proposed global method performs successfully to find and constrain the highly sensitive parameters efficiently that can facilitate application of the SWAP-EPIC model. [ABSTRACT FROM AUTHOR]

Large-scale agricultural activities can intensify atmospheric–terrestrial interactions, of which precipitation recycling plays a critical role. During 1982–2018, irrigated area has dramatically expanded in Northwest China (NWC). In this study, a regional precipitation recycling model—the Brubaker model was used to investigate the precipitation recycling ratio (PRR) and recycled precipitation (RP). Evapotranspiration (ET) estimated by the atmospheric–terrestrial water balance method (A–T) was employed to investigate precipitation recycling. Statistically, there was a turning point in 2002 for the rate in irrigated area increase, from 0.07 × 106 ha/year before 2002–0.217 × 106 ha/year after 2002. There were significant shifts in ET , PRR, and RP in NWC, using the turning point of irrigated area expansion as the line of demarcation. The contribution of the change in irrigated area to PRR increased from 18.3% (1982–2002) to 22.9% (2003–2018) in NWC. Prior to 2002, enhanced RP offset the increased ET by 72.9%. After 2002, the positive effect of irrigated area expansion on precipitation recycling disappeared in NWC. Due to the different climate and irrigation practices at the province level, the variations in irrigated area and their contributions to PRR were examined in three provinces, Xinjiang, Gansu, and Shaanxi. Results based on the Brubaker model and Budyko framework indicate that in Xinjiang and Gansu, the contribution of the irrigated area change after the turning point to PRR were 24.5% and -95.6%, respectively, and there is no potential for continued expansion of irrigated area. In Shaanxi, however, there is potential for continued expansion of irrigated area. The methodology for quantifying the impact of irrigated area change on PRR provides reliable references for the sustainable use of cultivated land and the protection of agricultural water resources. • Enhanced recycled precipitation offset ET increase induced by irrigated area expansion before 2002 in Northwest China. • Irrigated area in Northwest China exceeded the threshold and had the opposite effect on precipitation recycling ratio after 2002. • There is potential for continued expansion of the irrigated area in Shaanxi. [ABSTRACT FROM AUTHOR]

Saline-alkali soils seriously restrict agricultural productivity, reduce carbon (C) sequestration and increase global warming potential (GWP) of farmland systems. Straw return is usually used to improve soil physicochemical properties, increase soil organic carbon (SOC) and crop yield in saline-alkali arid farmland. The performance of straw return is influenced by varieties of factors including incorporation mode, soil type, crop and climate. Therefore, from 2017 to 2019, a three-year short-term study was conducted to investigate the impact of different straw return modes on soil greenhouse gas (GHG) emissions, net ecosystem C budget (NECB), net global warming potential (NGWP) and C footprint in a saline-alkali farmland under arid conditions. Four straw return modes, namely straw return with rotary tillage, straw return with plowing, and straw-derived biochar treatment and a control without straw return, were conducted in saline-alkali arid farmland. Results indicated that compared with the control, straw return with rotary tillage increased direct GHG emissions (soil borne CO 2 and N 2 O emissions), while straw-derived biochar decreased direct GHG emissions. Straw return with plowing had no significant impact on direct GHG emissions. Straw return with plowing, straw return with rotary tillage, and straw-derived biochar significantly increased indirect CO 2 emissions due to more consumption of energy, fossil fuels and diesel than the control. For C sequestration, straw return significantly increased crop C fixation and soil C sequestration compared with the control. The C sequestration in straw-derived biochar treatment was significantly higher than that of the return with rotary tillage and plowing treatments, thus achieving the highest NECB and the lowest NGWP and yield-scaled C footprint. Compared to the control, straw-derived biochar mode increased NECB by 2618.4−11379.4 kg ha−1, and decreased NGWP and yield-scaled C footprint by 12660.4−43431.9 kg ha−1 and 0.03−1.9 kg kg−1, respectively. Overall, the short-term results suggested that crop C fixation and soil C sequestration are crucial determinants of the NECB and C footprint, respectively. Return in the form of biochar could be recommended as an appropriate straw return practice for enhancing C sequestration and mitigating the GWP of the saline-alkali farmland. • Crop-soil systems C sequestration are crucial determinants of the NECB and C footprint. • Direct return of straw caused a low NECB and a high C footprint. • Biochar treatment achieved the highest NECB and the lowest C footprint. [ABSTRACT FROM AUTHOR]

Updated and accurate land cover maps are essential and crucial for sustainable crop production and efficient land management. However, accurate and efficient land cover mapping is still a challenge for agricultural regions with complicated landscapes. This study proposed a novel spectral-phenological based land cover classification (SPLC) method to identify the land cover for fragmented agricultural landscapes, with less requirement of ground truth data. The SPLC method integrated a pixel-based support vector machine (SVM) algorithm for cropland and various non-cropland classification, and a phenology-based automatic decision tree algorithm for identification of various crop types. It was then tested and applied in two typical case areas (i.e., Jiyuan in the upstream and Yonglian in the downstream) of Hetao Irrigation District (Hetao) in the upper Yellow River basin (YRB), northwest China. The field survey sampling data and the regional visual interpretation maps were jointly used to evaluate the accuracy of land cover classification. Results indicated that stable phenological rules can be established for crop identification even with complex planting patterns, and the SPLC method performed well in land cover mapping in case areas. Four high-accuracy land cover maps were produced for Jiyuan in 2020 and 2021, Yonglian in 2021, and Hetao in 2021. The overall accuracies (OA) can reach 0.90–0.94 based on evaluation with abundant ground truth data, and land cover maps agreed well with the visual interpretation maps in space. Overall, the case application validated the applicability and efficiency of the SPLC method in land cover mapping for regions with fragmented agricultural landscapes, and also implied the potential use in other similar regions. [ABSTRACT FROM AUTHOR]

Evapotranspiration is the main way of soil water depletion in field, and soil evaporation is an important part of evapotranspiration, and it may account for 32%-50% of the total evapotranspiration during the whole crop growth period. Soil evaporation does little effect on the formation of crop biomass and yield, so reducing soil evaporation is important for improving water use efficiency and agricultural water saving management. In recent years, straw mulching has been used widely due to its capability of improving soil structure, increasing soil organic matter, reducing soil evaporation and maintaining soil water content. Mulching affects exchange of energy and heat between soil surface and free air, so the mechanism for soil evaporation under mulching condition may be different from that without mulching. Considering the fast development of straw mulching, therefore modeling soil evaporation under straw mulching is of important for making agricultural water management. In this paper, the factors (soil water content and mulching amount) that affect soil evaporation had been analyzed, the values of mulching resistance were calculated, the equations for calculating resistance of mulching and the resistances of soil evaporation and soil evaporation under straw mulching had been established, the parameters for the equation had been determined. The experiment was carried out from late July to middle August in 2010 and from middle July to middle August in 2011, respectively. The undisturbed soil with winter wheat plants was prepared and put into plastic buckets when winter wheat was maturity, two main treatments (stubble and stubble+mulch treatments) were set up, there were five sub-treatments for each of the two main treatments. The stubble heights for stubble treatments were 0, 5, 15, 25, 35cm. Stubble heights were 0, 5, 15, 25, 35 cm with mulching amounts of 0.47, 0.43, 0.348, 0.267, 0.187 kg/m2 in stubble+mulch treatment, respectively. The total biomass (stubble biomass) for each stubble treatment was 0, 0.04, 0.122, 0.203, 0.283 kg/m2, respectively; the total biomass (stubble biomass and mulching amount) in each stubble+mulch treatment was 0.47 kg/m2. During the prepared period, water was applied to the soil until all the soil in the plastic bucket was saturated, and then the excessive water was discharged out off plastic bucket through small hole at the bottom of plastic bucket to make sure soil water content was about field capacity at the beginning of the experiment. The soil evaporation and soil temperature were measured daily and soil water content in 0-2 cm depth was measured every 2 ~ 5 days according to the soil evaporation. Meteorological data, including relative humidity, hourly mean air temperature, and wind speed were measured with an automatic weather station. Results showed that the relative soil evaporation (the ratio of soil evaporation to water evaporation from 20 cm diameter pan) kept relatively stable when soil water content was higher than 0.23 cm3/cm3 (60% field capacity), the ratio declined linear with the decreasing of soil water content when soil water content was higher than 0.05 cm3/cm3 (wilting point) and less than 0.23 cm3/cm3. Mulching affected soil evaporation, reducing stubble height and increasing mulching amount could reduce soil evaporation when the total biomass was the same. The total amount of soil evaporation during experiment period reduced by 8%-51% under stubble+mulch treatment with mulching amount of 0.348-0.47 kg/m2 compared with stubble treatment when stubble height was 0-15 cm. Mulching resistance was 158-600 s/m in this study and it was exponentially increasing with the mulching amount, and the resistance of soil layer decreased linearly with the soil water content increasing when soil water was less than 0.23 cm3/cm3 and higher than 0. 05 cm3/cm3. The validation processes showed that the developed method and related parameters (mulching resistance and the resistance of soil layer) performed well for modeling soil evaporation under mulching condition. [ABSTRACT FROM AUTHOR]

The paper adopted the method of using "the first successfully matched table" for the data extraction which is correct in cases where the consolidated statement comes first and the parent company statement comes second. However, using this method some of the financial data used came from the parent company while some of the data came from consolidated statements. [Extracted from the article]

The flow and transport in porous media are highly dependent on the internal structure and morphology of the pore space. The pore structure is determined by the size and geometrical shape of the solid particles, as well as their distribution and arrangement. In this study, the effect of grains surface morphology on the internal pore structure as well as the flow and transport properties of porous media were quantitatively analyzed using the pore-network approach, with angular quartz sand and round glass beads used as the test substrates. The surface morphology of the grains was visualized through scanning electron microscopy and quantified by Fourier morphological analysis. The pore structure of randomly packed quartz sand and glass beads was visualized using X-ray computed tomography and quantified using the network parameters. The surface morphology of grains with different angularities was distinguished by the shape and angularity parameters calculated from the Fourier representations. The network parameters, including mean coordination numbers, mean pore-body radii, and mean pore-throat radii, of randomly packed angular sand were larger than those of round beads within the same sieving size range. The intrinsic permeability and longitudinal dispersivity in the vertical direction were smaller than those in the horizontal direction, which indicates anisotropic compaction. The intrinsic permeability nonlinearly (power-law) varied with the pore and throat radii of the different extracted networks. The relation between intrinsic permeability and porosity of anisotropic porous media with different grain morphologies followed the Kozeny–Carman equations. Breakthrough curves in the representative elementary volumes of angular sand and round beads exhibited Fickian behavior. The longitudinal dispersivity decreased with an increase in the coordination number regardless of the grain morphology. [ABSTRACT FROM AUTHOR]