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River water plays a critical role in riparian plant water use and riparian ecosystem restoration along losing rivers (i.e., river water recharging underlying groundwater). How to quantify the contributions of river water to the transpiration of riparian plants under different groundwater levels and the related responses of plant water use efficiency is a great challenge. In this study, observations of stable isotopes of water (δ2H and δ18O), 222Rn , and leaf δ13C were conducted for the deep-rooted riparian weeping willow (Salix babylonica L.) in 2019 (dry year) and 2021 (wet year) along the Chaobai River in Beijing, China. We proposed an iteration method in combination with the MixSIAR model to quantify the river water contribution to the transpiration of riparian S. babylonica and its correlations with the water table depth and leaf δ13C. Our results demonstrated that riparian S. babylonica took up deep water (in the 80–170 cm soil layer and groundwater) by 56.5 % ± 10.8 %. River water recharging riparian deep water was an indirect water source and contributed 20.3 % of water to the transpiration of riparian trees near the losing river. Significantly increasing river water uptake (by 7.0 %) and decreasing leaf δ13C (by - 2.0 ‰) of riparian trees were observed as the water table depth changed from 2.7 m in the dry year of 2019 to 1.7 m in the wet year of 2021 (p<0.05). The higher water availability probably promoted stomatal opening and thus increased transpiration water loss, leading to the decreasing leaf δ13C in the wet year compared to the dry year. The river water contribution to the transpiration of riparian S. babylonica was found to be negatively linearly correlated with the water table depth and leaf δ13C (p<0.01). The rising groundwater level may increase the water extraction from the groundwater and/or river and produce a consumptive river-water-use pattern of riparian trees, which can have an adverse impact on the conservation of both river flow and riparian vegetation. This study provides new insights into understanding the mechanisms of the water cycle in a groundwater–soil–plant–atmosphere continuum and managing water resources and riparian afforestation along losing rivers. [ABSTRACT FROM AUTHOR]

This study reports the development and validation of a questionnaire to assess the holistic development of students with special educational needs (SEN) as a reliable instrument for measuring their overall performance in inclusive education. The survey was administered to 981 regular education teachers in Beijing. The identified factor structure contained six dimensions: Academic Performance (AP), School Adaptive Skills (SAS), Social Rules (SR), Motor Ability (MA), Interpersonal Relationships (IR), and Behaviour Management (BM). The data showed that students with SEN gained in the IR, SAS, SR and BM domains. These domains are more closely related to social and life skills than AP, which received the lowest scores. Student development in different domains varied depending on demographic variables, including student characteristics, learning environment and regular education teachers. The findings suggest that teachers prioritise the abilities of students with SEN to adapt to 'learning' and 'life' in inclusive schools. The presence of students with SEN in inclusive schools is a longstanding challenge facing Chinese inclusive education. There remains a long way to go to realise the goal of equitable and appropriate education for all. Continuous reform should be strengthened to support a more equitable education system with increased training and support for inclusive schools in China. [ABSTRACT FROM AUTHOR]

• Water use of riparian trees under various water table depth (WTD) along a losing river was determined. • Riparian trees accessed more upper soil water and had lower leaf δ13C under deep WTD compared to shallow WTD. • Water source contribution was a parabolic function of WTD and 2.1 m was the optimum WTD to utilize deep water. • Leaf δ13C had a positive linear relation with proportional contribution of deep water. Rivers losing flow into surrounding aquifers ('losing' rivers) are common under changing climates and groundwater overexploitation. The riparian plant-water relations under various water table dynamics along a losing river remain unclear. In this study, the water isotopes (δ2H and δ18O), leaf δ13C, and MixSIAR model were used combinedly for determining the root water uptake patterns and leaf water use efficiency (WUE) of Salix babylonica (L.) at three sites (A, B, and C) with different water table depths (WTDs) in the riparian zone of Jian and Chaobai River in Beijing, China. The correlations of water source contributions with WTD and WUE were quantified. The riparian S. babylonica primarily took up upper (0–80 cm) soil water (71.5%) with the lowest leaf δ13C (−28.8 ± 1.1 ‰) at site A under deep WTD (20.5 ± 0.5 m). In contrast, deep water below 80 cm depth including groundwater contributed 55.1% to S. babylonica at site B with fluctuated shallow WTD (1.9 ± 0.4 m), where leaf δ13C was highest (−27.9 ± 1.0 ‰). The S. babylonica mainly used soil water in 30–170 cm layer (56.9%) with mean leaf δ13C of − 28.2 ‰ ± 0.7 ‰ at site C with stable shallow WTD (1.5 ± 0.1 m). It was found that both the contributions of upper soil water in 0–80 cm and deep water below 80 cm had significantly quadratic correlations with WTD under shallow water table conditions (p < 0.05). Leaf δ13C was negatively correlated with contributions of upper soil water above 80 cm depth, but it was positively related to the contributions of deep water below 80 cm in linear functions (p < 0.001). The results indicated that 2.1 m was the optimum WTD for riparian trees, because they maximized the use of deep water sources to get the highest WUE. This study provides insights into managing groundwater, surface water resources and riparian afforestation in losing rivers. [ABSTRACT FROM AUTHOR]

Abstract: The evaluation of the field water cycle under deficit irrigation plays an important role in studying mechanism of field water dynamics, optimization of agricultural water management strategies, and assessment of regional water resources. In this study, the agro-hydrological Soil–Water–Atmosphere–Plant (SWAP) model was used to evaluate the field water cycle for a winter wheat-summer corn double cropping system in Beijing, China under deficit irrigation. A carefully designed field experiment was carried out from 2007 to 2009 with six irrigation treatments. The SWAP model was calibrated with soil water contents of two treatments. The dataset of the main field water balance components including soil water content, profile water storage and water flux through the bottom of the root zone were used to validate the SWAP model. The average root mean square error (RMSE) and the mean relative error (MRE) values of predicted soil water contents were 2.4% and 8.0%, respectively. The dataset of predicted and measured values were close to the 1:1 scale line for both the profile water storage and soil water flux. As an application of the SWAP model, the optimal irrigation management practices for the hydrologic years of 75%, 50% and 25%, respectively, in the Beijing area were obtained. The simulated average amount of water saving and groundwater recharge under the optimal irrigation schedules were about 190 mm and 16.1 mm, respectively. This study indicates that the SWAP model can be used as a powerful tool to simulate the field water cycle and evaluate irrigation practices. [Copyright &y& Elsevier]

Objective: To explore the vulnerability to HIV infection and related risk behaviors of the out-of-school adolescents who migrated with their parents from rural areas to cities. Methods: From September to October 2005, 260 out-of-school adolescents aged 14-20 years were interviewed through a questionnaire. Results: Out-of-school adolescents lacked HIV/AIDS knowledge and related life skills, and their psychosocial competency was relatively low. The interviewed adolescents were open in their sexuality, showing a low rate of condom use. Their attitudes towards people living with HIV/AIDS and HIV/AIDS prevention competency were positively correlated with family well-being, harmonious relations between their parents, a stable job, knowledge, life skill, and psychosocial competency for emotion control and empathy. Conclusion: Out-of-school adolescents are highly vulnerable to HIV/AIDS infection and transmission. Practical and feasible health and life skill education and psychosocial competency are the keys to effective HIV/AIDS prevention among out-of-school adolescent migrants. [Copyright &y& Elsevier]

Background: Knowledge remains limited about dairy consumption and childhood depression and social anxiety, which is our purpose.Methods: A cross-sectional study including children and adolescents aged 7-17 years was conducted in 2020 in Beijing. Depression and social anxiety were assessed using the Children's Depression Inventory and the social anxiety scale for children. Habitual dairy consumption was defined as ≥6 days/week. Multivariate linear and logistic regression models were employed to analyze the associations between dairy consumption and depression and social anxiety. Subgroup analyses were conducted to test the robustness of the main results.Results: A total of 1353 participants were included, with a mean age of 12.06 (SD = 3.10) years old. There were 53.58 % habitual dairy consumers and nearly 11.01 % consumed of ≤1 day/week. The prevalence of depression and social anxiety was 14.04 % and 29.64 %. Compared to participants with less dairy intake, the scores of depression and social anxiety in habitual dairy consumers decreased by 1.725 (95 % CI: -2.939, -0.512) and 1.083 (95 % CI: -1.821, -0.345). Correspondingly, habitual dairy consumption was inversely correlated with depression (OR = 0.602, 95%CI: 0.369-0.982) and social anxiety (OR = 0.622, 95%CI: 0.418-0.923). Such inverse associations were more pronounced in younger participants, those without siblings, with higher parental education and higher consumption of fruits or vegetables.Limitations: Conclusions about causality remain speculative due to the cross-sectional design.Conclusions: Habitual dairy consumption is inversely associated with childhood depression and social anxiety. A potential attempt could be implemented when recommending dairy products as an adjuvant therapy for childhood mental disorders. [ABSTRACT FROM AUTHOR]

Some of the rivers in northern China are dried, and reclaimed water (RW) is used to restore these degraded river ecosystems, during which the RW could recharge the aquifer by river bank infiltration. From 2007 to 2018, 2.78 × 108 m3 of RW has been replenished to the dried Chaobai River (Shunyi reach), Beijing, China, which is located on the edge of one depression cone in groundwater caused by groundwater over-pumping. The groundwater hydrodynamic variations and the flow path of the RW were identified by eight-year hydrological, hydrochemical, and stable isotopic data, together with multivariate statistical analysis. The RW infiltration drastically impacts the groundwater dynamics with a spatiotemporal variation. The 30-m depth groundwater levels at Perennial intake reach increased quickly around 3 m after 2007, which indicated that they were dominated by RW infiltration. Other 30-m depth groundwater levels were controlled by precipitation recharge from 2007 to 2011, showing significant seasonal variations. In 2012, with more RW transferred to the river, the hydrodynamic impact of the RW on 30-m depth aquifer expanded downstream. However, the 50-m and 80-m depth groundwater levels showed decreasing trend with seasonal variations, due to groundwater pumping. The 30-m depth aquifer was mainly recharged by RW, being evidenced by the enriched δ2H and δ18O. The depleted δ2H and δ18O of the 50-m and 80-m depth groundwater indicated that they were dominated by regional groundwater with meteoric origin. The heterogenous properties of the multi-layer alluvial aquifer offer the preferential flow path for RW transport in the aquifers. The proportion of the RW in the aquifers decreases with depth that was calculated by the chloride conservative mixing model. The increased lateral hydraulic gradient (0.43%) contributes to the RW transport in the 30-m depth aquifer. RW usage changed 30-m depth groundwater type from Ca·Mg-HCO3 to Na·Ca·Mg-HCO3·Cl. RW preferentially recharged the 50-m and 80-m depth aquifers by vertical leakage. [ABSTRACT FROM AUTHOR]

• Potential water source line (PWL) was proposed to correct δ2H offset of stem water. • PWL was assessed using riparian trees at three sites with different water tables. • Water source identifications were compared among seven types of input isotope data. • Dual isotopes with PWL-corrected δ2H obtained higher groundwater contribution. Root water uptake plays an important role in water cycle in Groundwater-Soil-Plant-Atmosphere-Continuum. Stable isotopes (δ2H and δ18O) are effective tools to quantify the use of different water sources by plant roots. However, the widespread δ2H offsets of stem water from its potential sources due to δ2H fractionation during root water uptake result in conflicting interpretations of water utilization using stable isotopes. In this study, a potential water source line (PWL), i.e., a linear regression line between δ18O and δ2H data of both soil water at different depths and groundwater, was proposed to correct δ2H offsets of stem water. The PWL-corrected δ2H was determined by subtracting the deviation between δ2H in stem water and PWL from the original value. The MixSIAR model coupled with seven types of input data (i.e. various combinations of single or dual isotopes with uncorrected or corrected δ2H data by PWL or soil water line (SWL)) were used to determine seasonal variations in water uptake patterns of riparian tree of Salix babylonica (L.) along the Jian and Chaobai River in Beijing, China. These methods were evaluated via three criteria including Akaike Information Criterion (AIC), Bayesian Information Criterion (BIC) and root mean square error (RMSE). Results showed that different types of input data led to considerable differences in the contributions of soil water at upper 30 cm (9.9–57.6%) and below 80 cm depths (29.0–76.4%). Seasonal water uptake patterns were significantly different especially when δ2H offset was pronounced (p < 0.05). The dual-isotopes method with uncorrected δ2H underestimated the contributions of soil water in the 0–30 cm layer (by 30.4%) and groundwater (by 56.3%) compared to that with PWL-corrected δ2H. The PWL correction method obtained a higher groundwater contribution (mean of 29.5%) than that estimated by the SWL correction method (mean of 24.5%). The MixSIAR model using dual-isotopes with PWL-corrected δ2H produced the smallest AIC (94.1), BIC (91.9) and RMSE values (4.8%) than other methods (94.9–101.7, 92.6–99.5 and 5.3–12.4%, respectively), which underlined the best performance of PWL correction method. The present study provides crucial insights into quantifying accurate root water uptake sources even if δ2H offset exists. [ABSTRACT FROM AUTHOR]

Long-term wastewater and reclaimed water irrigation systems constitute the major processes in local water circulation, which concomitantly introduce plenty of undesirable substances that can threaten water quality, ecosystem functions and human health. At the Southeast Reclaimed Water Irrigation Region (SRWIR) of Beijing, wastewater irrigation was adopted from 1969 to 2002, and second-treated effluents (reclaimed water) has been used thereafter. Polycyclic aromatic hydrocarbons (PAHs) were the most ubiquitously detected contaminant in wastewater and reclaimed water and are reported to be carcinogenic. Hence, we measured the concentrations of dissolved sixteen United States Environmental Protection Agency (USEPA) priority PAHs in surface water and groundwater at the SRWIR to characterize their spatial and temporal variations, and to clarify the role of reclaimed water to natural water. The concentration of 16 individual PAHs in reclaimed water, rivers and groundwater varied from 339.4 to 636.2 ng/L, 359.1 to 3,435.0 ng/L and 216.5 to 488,205.2 ng/L, respectively. The lower aromatic rings of PAHs prevailed in aquatic environments rather than the higher ones. Thereinto, naphthalene was the predominant isomer within the highest concentration reached to 486,600 µg/L. The groundwater samples had higher PAHs concentrations at Tongzhou district which attributed to the higher vulnerability of aquifer. Additionally, strong correlations between PAHs and total nitrogen, nitrate, dissolved oxygen and electrical conductivity suggested those potential factors affecting the photo degradation and/or biodegradation of PAHs. The relationship identified between PAHs concentrations and physical and chemical indices would help us to enhance the understanding migration and transformation of PAHs spatially and temporally, enable us to assess the potential risks of the environmental pollutants to aquatic organisms and human water supplies. [ABSTRACT FROM AUTHOR]

Sleep has been suggested as risk factors for depression and social anxiety in children and adolescents, but little is known about the role of individual body composition on these association. We conducted a cross-sectional survey of children and adolescents aged 6–18 years in Beijing, China, in 2020, and assessed body composition by using iDXA dual-energy X-ray bone densitometer. Generalized liner model (GLM) and restricted cubic spline (RCS) were employed to analyze the associations between sleep and depression and social anxiety with different body composition. The attributable fraction (AFs) to assess the benefits of improvements of sleep in reducing depression and social anxiety odds. Depression and social anxiety accounted for 13.1 % and 30.3 % of the study population. Sleep time was significantly associated with depression (HR = 2.35[1.58, 3.50]), and social anxiety (HR = 1.65[1.24, 2.20]); and sleep quality was significantly associated with depression (HR = 7.27[4.87, 10.84]), and social anxiety (HR = 2.54 [1.99, 3.25]) among children and adolescents. The exposure to both insufficient sleep time and poor sleep quality were associated with a higher odd of depression and social anxiety, but lower BF%, higher muscle rate and FFM/FM alleviated the adverse effects of sleep quality on depression and social anxiety. Conclusions about causality remain speculative because of the cross-sectional design. Insufficient sleep time, poor sleep quality, high BF%, low muscle rate and FFM/FM can jointly associate with anxiety and depression. This study provides new evidence support for accurate prevention and control of mental diseases in children and adolescents with different body types. •.A cohort study used iDXA was to explore the associations with different body composition. • The exposure to both insufficient sleep time and poor sleep quality were associated with depression and social anxiety. • Lower BF%, higher MR and FFM/FM alleviated the effects of sleep quality on depression and social anxiety. • Good sleep quality theoretical benefited more in children with higher BF%, lower MR and FFM/FM. • This study provides evidence for accurate prevention of mental diseases in children with different body composition. [ABSTRACT FROM AUTHOR]