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Forest litter is an important guarantee for maintaining forest soil fertility and circulating material in forest ecosystems. The input of litter plays an important role in soil organic matter formation and biogeochemical cycles in forest ecosystems. However, the production and elements concentrations of Juniperus przewalskii (JP) litter in the Qilian Mountains are still unknown. In this study, we investigated the production of needle, branch and bark, cone, and impurity litters. We determined the concentrations and fluxes of major (K, Mg, Al, and Fe) and trace (Na, Mn, Zn, Cr, Ni, Cu, Pb, Co, Cd, and Ag) elements in needle litter of JP from September 2020 to August 2021. The results showed that the annual litter production was 4040.74 ± 495.96 kg ha−1 a−1. Needle and cone litters were the main components of the total litter production. The major elements (MEs) and trace elements (TEs) fluxes of litter were consistent with the litter production trend. The concentrations and fluxes of MEs and TEs in needle litter decreased in the order: K > Mg > Al > Fe > Na > Mn > Zn > Cr > Ni > Cu > Pb > Co > Cd > Ag. These results have important implications for understanding the migration processes of MEs and TEs in forest ecosystems of the Qilian Mountains. [ABSTRACT FROM AUTHOR]

Due to climate change and human activities, the eco-environment quality (EEQ) of eco-fragile regions has undergone massive change, especially in the Tibet Plateau. The Qilian Mountains (QLM) region is an essential ecological function zone in the northeastern Tibet Plateau, which plays a vital role in northwestern China's eco-environmental balance. However, EEQ changes in the QLM during the 21st century remain poorly understood. In this study, the spatiotemporal variations of the EEQ in the QLM were analyzed from 2000 to 2020 using a remote sensing ecological index (RSEI). The EEQ driving factors are identified by the geographic detector, and the spatial influence of critical factors is represented by a geographically weighted regression model. The results show low EEQ in the QLM. From 2000 to 2020, the EEQ initially slightly improved, then deteriorated, and finally gradually recovered. Spatially, the EEQ shows an increasing trend from northwest to southeast. Moran's I of EEQ remains at around 0.95, representing high spatial aggregation. "High–High" and "Low–Low" clustering features dominate in the local spatial autocorrelation, indicating the EEQ of the QLM is polarized. Precipitation is the dominant positive factor in the EEQ, with a q statistics exceeding 0.644. Furthermore, the key factors (precipitation, distance to towns, distance to roads) affecting EEQ in different periods vary significantly in space. From results we can draw the conclusion that the natural factors mainly control the spatial patterns of EEQ, while the human factors mainly impact the temporal trend of EEQ, the EEQ in the QLM has been significantly improved since 2015. Our findings can provide theoretical support for future eco-environmental protection and restoration in the QLM. [ABSTRACT FROM AUTHOR]

Precipitation patterns are vital to water resource management and hydrological research, especially in the upper reaches of inland rivers in arid and semiarid areas. However, estimating spatiotemporal precipitation patterns at a basin scale is challenging due to limited observations. In this study, spatiotemporal patterns of precipitation amount, frequency, duration, and intensity at different time scales from 2014 to 2019 are estimated using the Bayesian maximum entropy method in the Tianlaochi catchment of the Heihe River watershed, northwest China. The study's results show that the annual average precipitation amount was 535.9 mm from 2014 to 2019, with precipitation amount between May and September accounting for 85.9% of the annual precipitation amount. For daily precipitation, the average frequency rate of light precipitation is highest at 59.55%, however, the average contribution rate of moderate precipitation is highest at 50.33%. The spatial distribution of precipitation is characterized by high-value areas concentrated in the central valley and low-value areas located at the catchment's outlet. The most important driving factors of precipitation patterns are elevation, relative humidity, and wind direction. These outcomes can be used to establish accurate hydrological models in the catchment and provide support for water resource management in the Heihe River watershed. [ABSTRACT FROM AUTHOR]

Studies on subsequent effects of Cu pollution on mineral nutrients uptake in different tissues of crops grown in sierozem are limited. A pot experiment was conducted to reveal the effects of exogenous Cu on the accumulation and translocation of Cu and the interaction with nutrients in different tissues of wheat in Cu-polluted sierozem in northwest China. Results showed that the average concentration of Cu in different tissues of wheat was roots > stems and leaves > grains > shells. The bioaccumulation factor (BCF) of Cu in different parts of wheat was roots > stems and leaves > grains > shells. There was a weak translocation of Cu from sierozem to tops of wheat. Furthermore, the translocation ability of Cu from roots to tops of wheat was increasingly weak with increasing Cu stresses. Micronutrients (Fe, Mn and Ca) distribution in different wheat tissues indicated that uptake and upward translocation of these kinds of micronutrients could be affected by high soil Cu concentration. The addition of Cu in sierozem promoted the Mn absorption in wheat tissues, which may also be helpful to solve the lack of Mn in wheat caused by the Cu shortage in sierozem. [ABSTRACT FROM AUTHOR]

Background: The cumulative genetic effect of cholesterol metabolism (CM) pathway may be a candidate cause for disrupted brain network and impaired cognitive phenotypes, dependent on the pathological changes of Alzheimer's disease (AD) spectrum. We aim first to explore the relation of polygenic scores (PGS) underlying CM pathway with cerebrospinal fluid (CSF) biomarkers and cognition of AD, and second to investigate the role of genetic protective scores (GPS), genetic risk scores (GRS) and relative risk scores (RRS) of CM pathway on the anterior and posterior default mode network (aDMN and pDMN) trajectories across the AD spectrum. Method: We analyzed data of 113 participants of AD spectrum from the Alzheimer's disease Neuroimaging Initiative database, with demographic, global cognitive, genetic, CSF, and resting‐state functional MRI images at baseline available. Then PGS were calculated based on the odds ratio of minor allele. Linear and nonlinear regression were employed to explore the relationship between pairs of PGS, cholesterol metabolites in the blood, CSF biomarkers, and cognitive performance, and multivariate linear regression to investigate the main and interactive effect of PGS×disease on the DMN. Result: PGS of CM pathway were significantly correlated with levels of CSF biomarkers but not cognition directly. Several cholesterol metabolites were associated with t‐Tau but not p‐Tau and Aβ levels of CSF biomarkers, and the latter of which could impact cognitive performance in a nonlinear manner. In addition, CM related blood biomarkers could influence cognitive function directly. Further, accumulative effects of GPS, GRS, and RRS on the aDMN and pDMN were in absolutely diverse trajectories across the AD spectrum. However, brain regions of PGSΧdisease effects were mainly concentrated in the cortical frontal‐parietal network and subcortical basal ganglia network. There was also a certain rule for the brain maps of cholesterol metabolites associated with DMN, where sensory‐motor network and posterior cingulate cortex occupied. Conclusion: The cumulative genetic effect of CM pathway could affect DMN and cognition dependent on the pathological levels of AD and firstly demonstrated that protective genes, risky genes and relative risk within CM pathway had different trajectories effects on the subsystems of DMN across the AD spectrum. [ABSTRACT FROM AUTHOR]

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The in situ immobilization of metal-contaminated sediment, using various amendments, has attracted great attention owing to their cost-effectiveness. The present study investigated the effectiveness of Chinese loess on Cu, Zn, Cd and Pb stabilization by decreasing their bioavailability in contaminated sediment. The loess was mixed with the sediment in doses of 0, 0.5, 1, 2, 5, 10 and 20 kg. Approximately 70 d after loess application, the effectiveness was evaluated using the Tessier sequential extraction procedure and single extractants, including ethylenediaminetetraacetic acid disodium salt (EDTA-2Na), diethylenetriaminepentaacetic acid (DTPA), calcium chloride (CaCl 2 ) and hydrochloric acid (HCl). The results indicated that the loess can effectively transform Cu from the carbonate fraction into the residual fraction when the loess dose was ≥5 kg. However, loess had little effect on Zn, Cd and Pb immobilization. Correlation analysis showed that these four extractants can provide a good indication of the toxicity of Cu, Zn, Cd and Pb in the amended sediment. Additionally, the organic matter content in the amended sediment decreased by 1.4% for CK, 1.6% for L0.5, 1.7% for L1, 1.5% for L2, 1.5% for L5, 1.9% for L10 and 1.9% for L20 (CK: untreated sediment; L0.5 to L20 represent loess doses of 0.5, 1, 2, 5, 10 and 20 kg, respectively) compared to the initial organic matter content in the unamended sediment, which may increase the atmospheric carbon dioxide owing to the degradation of organic matter. [ABSTRACT FROM AUTHOR]

Background: Studies on motor performance and its early markers are rare in China, especially in very low birth weight (VLBW) infants.Objective: Apart from the assessment of the inter-scorer agreement, we aimed to analyze to what extent the motor repertoire at 10 to 18weeks postterm was related to neonatal complications, and gross and fine motor performance at 12months after term.Study Design: Exploratory prospective study.Subjects: Seventy-four VLBW infants (58 males; mean gestational age=29weeks; mean birth weight=1252g).Method: Five-minute video recordings were performed at 10 to 18weeks after term; fidgety movements and the concurrent motor patterns (resulting in a motor optimality score) were assessed according to the Prechtl general movements assessment (GMA). The gross and fine motor performance was assessed by means of the Peabody Developmental Motor Scales, second edition, at 12months.Results: Reliability was excellent. Pneumonia was associated with absent fidgety movements; the motor optimality score was lower in infants with pneumonia and/or bronchopulmonary dysplasia. Both absent fidgety movements and a lower motor optimality score were associated with a poor or very poor gross and fine motor performance at the 12-month-assessment.Conclusion: Both the assessment of fidgety movements and the evaluation of the concurrent motor repertoire contribute significantly to an identification of VLBW children with a poor gross and fine motor outcome at 12months. The results of this study document the need for an early identification of infants at high risk for a poor motor performance. [ABSTRACT FROM AUTHOR]

Effects of heavy metal on uptake of mineral nutrition elements in plants have attracted widespread interest and been widely explored. This paper reports the translocation and accumulation behaviors of Ni in the organs of mature wheat plants by means of pot experiment using the sierozem collected from northwestern China as experimental soil. Effect of Ni on accumulation of Cu, Mn, Ca, and Mg is also demonstrated. It was found that influence of Ni on wheat plants differed greatly at different Ni levels. Ni content in the organs of wheat plants increased with the increase in Ni level, and the increasing rate decreased when the Ni level was higher than 400 mg/kg. Ni was mainly accumulated in the roots and less distributed in the shoots, shells, and grains. When the Ni level was lower than 400 mg/kg, the bioconcentration factor (BCF) of the roots was higher than 1, suggesting that Ni was taken in against a concentration gradient. The average translocation factor (TF) of wheat plants was 0.221, indicating the weak ability of wheat plants in translocating Ni toward the aboveground parts. Since Ni is readily accumulated in the grains of wheat plants at lower Ni level, concerns in health risks might be raised. Excess Ni in wheat plants could inhibit the transfer of Cu, Mn, and Mg to grains, leading to the accumulation of Ca, Mg, and Mn in the shoots and shells of wheat plants. The increase in Ni content can disturb the uptake and distribution of mineral nutrition elements in the organs of plants, resulting in the toxic effect of Ni on wheat plants. Results from this study provide a scientific support to prevent or control heavy metal pollution in an arid region. [ABSTRACT FROM AUTHOR]

[Display omitted] • Concentrations of Cu in rainwater and Zn in particulate were the highest among TEs. • Forest soils had higher Pb, Ni concentrations and lower Cd, Hg concentrations. • The Zn, Ni, Pb, and Cu have accumulated in forest vegetation and tissues. The biogeochemical cycling of trace elements (TEs) in forest ecosystems is important because it plays a role in providing essential nutrients to plants and soils and because it can potentially have toxic effects. In this study, we investigated the concentration of TEs in atmospheric wet deposition, vegetation and soil in Qinghai spruce (QS) and Qilian juniper (QJ) forests of the Qilian Mountains. Our results show that the average concentrations of Cu in rainwater in QS and QJ forests were 10.30 and 5.35 μg L−1, respectively, the highest concentrations of all TEs in these environments. We suggest that the particulate matter present in the air was the main contributor of TEs in atmospheric wet deposition, which is affected by element specificity, regional factors, and the scavenging process during rainfall events. Most vegetation and tissues had high concentrations of Zn, Ni, Pb, and Cu, suggesting that these elements have accumulated in plants. The Zn, Pb, and Ni levels in forest plants may be correlated with those in forest soils. Our study highlights the role that atmospheric wet deposition can play in affecting TEs cycling across forest ecosystems. Managers need to further reduce TEs levels in emissions from surrounding sources and improve long-term observation of TEs in forest ecosystems. [ABSTRACT FROM AUTHOR]

Abstract: Though principle component analysis (PCA) and locality preserving projections (LPPs) are two of the most popular linear methods for face recognition, PCA can only see the Euclidean structure of the training set and LPP preserves the nonlinear submanifold structure hidden in the training set. In this paper, we propose the elastic preserving projections (EPPs) which by incorporating the merits of the local geometry and the global information of the training set. EPP outputs a sample subspace which simultaneously preserves the local geometrical structure and exploits the global information of the training set. Different from some other linear dimensionality reduction methods, EPP can be deemed as learning both the coordinates and the affinities between sample points. Furthermore, the effectiveness of our proposed algorithm is analyzed theoretically and confirmed by some experiments on several well-known face databases. The obtained results indicate that EPP significantly outperforms its other rival algorithms. [Copyright &y& Elsevier]

• Atmospheric wet deposition fluxes of TEs to forest were analyzed in Qilian Mountains. • Similarities and differences of wet deposition were discussed in two forest stands. • Potential influencing factors of TEs in wet deposition were investigated. • Three major sources were identified for particulate matter. • Industrial activities and waste incineration were the largest contributors of PM. Atmospheric deposition is the main pathway by which trace elements (TEs) enter the terrestrial ecosystems, but few studies have investigated atmospheric TE deposition in remote forests. To understand the concentration, fluxes, influencing factors, and sources of TEs in atmospheric wet deposition, 104 samples from 13 rainfall events in two forest stands of the Qilian Mountains between July and September 2018 were collected and analyzed for eight TEs. The order of volume-weighted mean (VWM) concentration of TEs was Cu > Pb > Ni > Cr > Cd > As > Hg. Cu was the most abundant TE, with VWM concentrations of 6.33–10.90 μg L−1 in Qinghai spruce (Picea crassifolia Kom.) forest and 3.21–7.48 μg L−1 in Qilian juniper (Juniperus przewalskii Kom.) forest, which were 2 or 3 orders of magnitude higher than those of Hg, respectively. The wet deposition fluxes of TEs in Qinghai spruce forest were larger than those in Qilian juniper forest. The rainfall amount, rainfall intensity, rainfall duration, relative humidity, and wind speed were found to be important factors influencing atmospheric TE deposition. Based on correlation analysis, Principal Component Analysis (PCA) and Positive Matrix Factorization (PMF) modeling, three major sources of particulate matter (PM) were identified, namely industrial activities and waste incineration, traffic emissions and coal combustion, and biomass burning. Industrial activities and waste incineration were the dominant contributors, accounting for 79% of PM mass. Our results confirm that long-range transport of TEs has a significant impact on remote forest ecosystems in the Qilian Mountains. [ABSTRACT FROM AUTHOR]

Contaminated mining sediment may cause environmental and human health risk due to potentially hazardous elements (PHEs) leaching into groundwater, especially under very acid (pH ≤ 3) conditions. The capability of Chinese loess to immobilise and retain copper (Cu), zinc (Zn), cadmium (Cd) and lead (Pb) from element contaminated mining sediment was explored by a column leaching experiment. Results showed that loess could effectively reduce Cu geomobility, and their leachate concentrations were lower than the quality standard (1.0 mg L−1) for ground water in China. The sierozem showed strong adsorption for Zn, Cd and Pb. The geomobility of Cu, Zn, Cd and Pb were affected by pH, electrical conductivity, organic matter and carbonate content of sediment/loess-amended sediment and sierozem. The long-term leaching of PHEs in loess-amended sediment may pose a potential risk to sierozem and groundwater in the region. This study highlights the need to develop a remediation technique to minimise the concentration level of hazardous elements in the mining sediment. Image 1 • Geochemistry of PHEs in loess-amended mining sediment was evaluated. • Sierozem showed strong adsorption for Zn, Cd and Pb but weak adsorption for Cu. • HNO 3 leaching decreased the pH, EC, OM and CaCO 3 content of different soil depths. [ABSTRACT FROM AUTHOR]

Considerable studies have been done on heavy metal removing from aqueous solutions using loess. However, application of loess to heavy metal contaminated sediment is limited. The present study was to determine the effectiveness of loess to immobilize Cu, Zn, Cd and Pb in sediment. The loess was incubated with 10 kg wet sediment in doses of 0, 0.5, 1, 2, 5, 10 and 20 kg for 70 d and then subjected to the toxicity characteristic leaching procedure (TCLP). The possible mechanisms for heavy metal immobilization were illustrated using X-ray diffraction and scanning electron microscope. Results from TCLP confirmed loess reduced leaching rate of Cu and Zn achieving up to 42.4% and 17.6% reductions, respectively, when compared with untreated sediment. The loess could significantly immobilize Cu and Zn in sediment, and the optimum dose of loess in 10 kg wet sediment was 5 kg. However, loess was inefficient for Cd and Pb immobilization. Correlation analysis showed that TCLP extraction method could be used to predict the toxicity of Cu, Zn, Cd and Pb in the loess-amended sediment. The pH, EC, OM and CaCO 3 of the loess-amended sediment played predominant roles in the TCLP leaching test. Image 1 • Heavy metal immobilization of dredged sediment using loess was evaluated. • Loess can effectively reduce TCLP leaching rate of Cu and Zn in dredged sediment. • TCLP could predict the toxicity of heavy metals in the loess-amended sediment. [ABSTRACT FROM AUTHOR]

Qinghai spruce forests play a key role in water conservation in the dry region of northwest China. So, it is necessary to understand the impacts of climate change on the species to implement adaptation strategies. Based on the four-emission scenario (i.e., RCP2.6 (Representative Concentration Pathway), RCP4.5, RCP6.0 and RCP8.5) set by the Intergovernmental Panel on Climate Change (IPCC) fifth assessment report, in the study, we predicted the potential distribution of Qinghai spruce (Picea crassifolia Kom.) under current and future scenarios using a maximum entropy (Maxent) model. Seven variables, selected from 22 variables according to correlation analysis combining with their contribution rates to the distribution, are used to simulate the potential distribution of the species under current and future scenarios. Simulated results are validated by area under the operating characteristic curve (AUC). Results demonstrate that elevation, mean temperature of wettest quarter, annual mean temperature, and mean diurnal range are more important in dominating the potential distribution of Qinghai spruce. Ratios of the suitable area to the total study area are 34.3% in current climate condition, 34% in RCP2.6, 33.9% in RCP4.5, 33.8% in RCP6.0, and 30.5% in RCP8.5, respectively. The warmer the climate condition is, the more area of higher suitable classification is changed to that of lower suitable classification. The ratios of real distribution area in simulated unsuitable class to the real distribution area change from 4.3% (60.7 km2) in the current climate to 13% (185 km2) in RCP8.5, suggesting that the real distribution area may decrease in the future. We conclude that there is a negative effect of climate change on the distribution of Qinghai spruce forest. The result can help decision-makers to draft adaptation countermeasures based on climate change. [ABSTRACT FROM AUTHOR]

Sulfur (S)-oxidizing microorganisms regulate S biogeochemistry in soil ecosystems, affecting ecosystem productivity and food quality. Elemental sulfur (S0) supplies SO 4 2− to plants after oxidation by S-oxidizing microorganisms, and soil pH, organic carbon, water content, and temperature affect the oxidative process. However, how soil water content and texture interact to affect S-oxidizing microbial communities and S0 oxidation is unclear. In this study, S0 oxidation rate and abundance and composition of microbial communities were examined in silty loam and sandy loam soils with different levels of water holding capacity (WHC) (20%, 40%, 60%). Total bacteria were analyzed using the 16S rRNA gene, S-oxidizing bacteria with soxB , and fungi with the ITS gene. The oxidation rate increased significantly with increases in WHC in the sandy loam soil but not in the silty loam soil. The difference might be because the interaction between water content and texture affected the area of contact between S0 and S-oxidizers. At 40% and 60% WHC, the oxidation rate was significantly higher in sandy loam soil than in silty loam soil. The higher oxidation rate was attributed to high ratios of soxB to 16S rRNA gene abundances and key oxidizers in the sandy loam soil. The ratio of soxB to 16S rRNA was significantly higher in the sandy loam soil than in the silty loam soil, irrespective of WHC. The sandy loam soil also contained abundant and diverse typical S-oxidizing bacteria and unknown soxB -containing bacteria. Differences in abundance and composition of S-oxidizing bacterial communities between the two soils might be caused by different cropping histories. [ABSTRACT FROM AUTHOR]

Abstract Untreated industrial sewage and domestic wastewater irrigation has led to agricultural soil-crop system contamination by heavy metals and fluoride in Dongdagou and Xidagou stream basins, Baiyin city, China. A total of 36 pairs of soil and wheat samples (roots, stalks, leaves, husks, and grains) and 42 pairs of soil and maize samples (roots, stalk1, stalk2, stalk3, leaves, husks, corncobs and grains) were collected from Dongdagou and Xidagou stream basins to examine the accumulation, fractionation, correlation of heavy metals and F in soil-crop systems. Risks posed by heavy metals and F in this system to human health was also assessed. The total contents of F and heavy metals (Cd, Cu, Pb, Mn Zn, Cr and Ni), as well as the fraction distribution in soil, were determined. The total contents of F and heavy metals in crop tissues were also determined. The results indicated that the average contents of Cd, Cu, Pb, Mn Zn, F and Cr in Dongdagou and Xidagou stream basins exceeded the soil background value. Heavy metals and F more easily accumulated in the male inflorescence of maize. Correlation analysis showed that content of water soluble F positively were correlated with the contents of Cd, Cu, Pb, Mn Zn, Cr and Ni in exchangeable and carbonate fractions (P < 0.05). Stepwise discriminant analysis showed that the combined stresses of soil total Cu and Ni accounts for 100% effect on water soluble F accumulation in soil and crop roots. The hazard index indicated that noncancerous risk is likely to occur through maize grains and wheat grains consumption by children and adults. Graphical abstract Unlabelled Image Highlights • Water soluble F may increase the bioavailability of Cu, Mn, Zn, Pb, Ni, Cd and Cr. • The combined stresses of Cu and Ni may be the main factor that increases F bioavailability. • Contaminants easily accumulate in male inflorescence of maize except for roots and leaves. • Crop grains and shoots cannot be used for food and feed consumption. [ABSTRACT FROM AUTHOR]

Soil fluoride (F) and cadmium (Cd) pollution are of great concern in recently years, due to the fact that considerable amounts of wastewater, gas and residue, containing F and Cd, have been discharged into the environment through ore smelting. Soil F and Cd contamination may result in their interaction in soil and plant, which affects their fractionation distribution in soil and accumulation in oilseed rape. Oilseed rape, which is widely planted and consumed as a popular vegetable in arid and semi-arid land of northwest China, has been believed to a hyperaccumulator for Cd. However, there is limited information about the accumulation, interaction and fractionation of F and Cd in soil-oilseed rape system under F-Cd stresses. A pot-culture experiment, with single (F or Cd) or double elements (F-Cd) being added to soil, was carried out study the accumulation, interaction and fractionation of F and Cd in sierozem and oilseed rape. We found that soil F applications increased the contents of Cd in exchangeable fraction (EX-Cd), the bound to carbonate fraction (CAB-Cd) and the bound to iron and manganese oxides fraction (FMO-Cd) in soil and also increased plant Cd accumulation. Therefore, we suggest that the permitted level of F should be confined within soil quality standards for farmland of China in order to upset the effect of high F concentration on bioavailability of soil Cd. However, soil Cd applications showed negative effects on the content of F in water soluble fraction (Water-F), hence decreased plant F accumulation. A better understanding of the accumulation, interaction and fractionation of F and Cd in sierozem-oilseed rape system are of great importance for environmental protection and for human health. The present study may serve as a basic understanding of the accumulation, interaction and fractionation of F and Cd in sierozem-oilseed rape system, and provide a suggestion for the environmental management. [ABSTRACT FROM AUTHOR]

Contamination of agricultural soil with high concentrations of fluorine (F) and cadmium (Cd) have raised significant concerns regarding their impacts on human health but the relationship between F and Cd in soil-wheat plant system in an oasis region has not been investigated. This paper aims to study the accumulation and interaction of F and total Cd in the soil-wheat plant system while considering the potential risks of F and Cd to human health. Soil samples were collected from wastewater-irrigated oasis regions, Dongdagou and Xidagou. The concentrations of total F (F T ) and Cd in soils from the Dongdagou and Xidagou stream basins were higher than those in uncontaminated soils (F = 270.25 mg kg − 1 , Cd = 0.10 mg kg − 1 ). Water-soluble F (F W ) and F T contributed to F concentrations in underground parts of wheat when the samples were collected from Dongdagou, however, F in aboveground parts may be mainly influenced by atmospheric F. The main source of F in wheat plants collected from the Xidagou site may be mainly controlled by atmospheric F, including aboveground and underground parts. Soils in the studied region pose a potentially severe health risk for humans via bioaccumulation of toxic metals through the food chain, and therefore, are not suitable for planting wheat meant for human consumption. Cd had a significantly negative effect on F accumulation in wheat root from Dongdagou ( P < 0.01). This field study provided F-Cd interactions that occur in soils from an oasis region at environmentally relevant concentrations. [ABSTRACT FROM AUTHOR]

The radish plants are cold- and drought-tolerant crops. They have been widely planted in semi-arid or arid areas of northwest China. With high biomass production, the radish plants have been proved to be a potential phytoaccumulator of several metals (Cu, Pb, Zn). A pot experiment with single element-contaminated or co-contaminated soils was conducted to study fluoride (F) and cadmium (Cd) accumulation in radish plants and the effect of their interaction on radish growth. After four months growing in sierozem, F and Cd with different concentration levels were added to the soil. The dry biomass and the concentrations of F and Cd in the roots and leaves of radish plants were measured, and the bioconcentration and translocation factors of F and Cd were calculated. We also identified the contents of Cu, Zn and Mn in radish plants. The combined contamination of F and Cd showed synergistic effect (negative) on the growth of radish plants. It was found that F or Cd was mainly accumulated in the leaves of radish plants which were able to transport to tops of radish plants. The addition of F-Cd inhibited Cu uptake by the roots, while the addition of F or Cd or F-Cd all promoted Zn absorption by radish plants. Results also showed that the synergistic interaction (positive) between F and Cd played a role in the absorption of Mn by the roots of radish plants. [ABSTRACT FROM AUTHOR]

Background Infants with normal fidgety movements at 3 to 5 months after term are very likely to show neurologically normal development, while the absence of fidgety movements is an early marker for an adverse neurological outcome, mainly cerebral palsy (CP). The clinical significance of so-called sporadic fidgety movements (i.e., fidgety movements occur isolated in a few body parts and are of 1- to 3-second-duration) is not yet known. Aims Our objective was to determine whether infants who had developed CP and had sporadic fidgety movements have a better outcome than infants who did not have fidgety movements. Study design Longitudinal study. Retrospective analysis of prospectively collected data. Subjects 61 infants who developed CP (46 male, 15 female; 29 infants born preterm; videoed for the assessment of movements and postures at 9 to 16 weeks post-term age). Outcome measures The Gross Motor Function Classification System (GMFCS) was applied at 3 to 5 years of age. Results There was no difference between children diagnosed with CP who had sporadic fidgety movements at 9 to 16 weeks post-term age (n = 9) and those who never developed fidgety movements (n = 50) with regard to their functional mobility and activity limitation at 3 to 5 years of age. One infant had normal FMs and developed unilateral CP, GMFCS Level I; the remaining infant had abnormal FMs and developed bilateral CP, GMFCS Level II. Conclusions There is no evidence that the occurrence of occasional isolated fidgety bursts indicates a milder type of CP. [ABSTRACT FROM AUTHOR]

[Display omitted] • Biochar effect on physics of sandy desert soil was investigated. • The effects were dependent on biochar particle size and dosage. • Biochar improved the soil water retention capacity and aggregate stability. • SSA played a key role in the response of soil to biochar application. • Biochar can be as a novel strategy to control aeolian desertification. Enhancing the resistance of sandy desert soil to drought and wind erosion is key to controlling aeolian desertification. Using biochar as an amendment can improve soil quality. This study aimed to determine the impacts of biochar particle size and application rate on the hydraulic and physical properties of sandy desert soil. Biochars were produced by pyrolyzing corn straw at 500 °C with limited oxygen. Samples of sandy desert soil were collected from the Tengger Desert in Northwestern China. Tests were designed with three biochar particle sizes (0–0.25, 0.25–1, and 1–2 mm) and five biochar application rates (wt%: 0, 0.5%, 1%, 2%, and 4%). Soil hydraulic and physical properties were characterized by the soil–water characteristic curve, soil porosity, soil specific surface area (SSA), and soil structural index (SI). The results showed that biochar significantly increased the soil porosity and the number of extreme micropores, micropores, and small pores. As a consequence, the saturated soil water content (θ s), permanent wilting point (PWP), field capacity (FC), and available water content (AWC) were significantly enhanced. The significant improvement in SI demonstrated that biochar enhanced the soil aggregate stability, therefore, the resistance of sandy desert soil to wind erosion is enhanced. Biochar dosage was a more important factor that influenced the FC, AWC, PWP, SI, and SSA of the soil more than biochar particle size. The properties of θ s , PWP, FC, AWC, and SI were all closely related to SSA, indicating that SSA played a key role in the mechanism affecting the response of the soil to biochar application. The significant increase in water retention and aggregate stability of sandy desert soil with added biochar suggests a novel strategy to control aeolian desertification by amending the soil. [ABSTRACT FROM AUTHOR]

• The LULC change features were the increase of forest and decrease of cultivated land. • Landscape ecological risk increased during 1986–2008 and declined during 2008–2015. • Human management intensities deeply affected landscape ecological risk in reserves. It is necessary to improve the ecological environment and keep ecological balance of nature reserves that have particularly important function on precious and endangered wildlife species conservation. Human activities give rise to the remarkable changes in land use/land cover (LULC) and further have an effect on the landscape and eco-environment in nature reserves. This study evaluated the landscape ecological risk based on LULC changes in Baishuijiang National Nature Reserve according to different management zones from 1986 to 2015. Results showed that the significant change characteristics of LULC were the increase of forest and the decrease of cultivated land from 1986 to 2015. The major LULC changes took place in the experimental zone, and there was 85.61 km2 cultivated land transferred to the forest. Generally, the ecological risk level was low, and the area percentages of the lowest and lower risk regions to the total area were all higher than 97% from 1986 to 2015. Moreover, the values of ecological risk were discrepant in different time, the order of that being 1986 < 2015 < 1995 < 2008. Combining the components of different ecological risk levels in every management zone, the ecological risk from low to high was the core zone, buffer zone, and experimental zone. The ecological risk tended to be aggregated in space during 1986–2008, and it was enhanced slightly from 2008 to 2015. This study focuses on Baishuijiang National Nature Reserve to provide assessment for environmental protection and ecological management in hope that the method can be applied to other national nature reserves in China. [ABSTRACT FROM AUTHOR]