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The middle and lower reaches of the Yangtze River, a primary region for freshwater lakes in China, have undergone significant transformations throughout the Holocene. These changes, driven by factors such as sea-level rise, climate change, and human activities, have led to the progressive elevation of water levels in this area. As a result, a floodplain has emerged, characterized by the formation of numerous shallow lakes along the river course. However, the pattern of water-level changes in the main channel of the Yangtze River during the Holocene remains unclear. This gap in knowledge poses challenges for understanding sediment transport dynamics, the interactions between the river and its adjacent lakes, and the prevention and control of flood disasters in the Yangtze River basin. To shed light on these issues, our study compiled data on the surface elevation and water depth of 81 lakes in the mid-lower reaches of the Yangtze River basin. Additionally, we analyzed historical water-level records from the 1900s to the 1970s at eight gauging stations from Shashi to Jiangyin along the river's main stream. Our findings reveal that, particularly along the Jingjiang section, the basal elevation of most lakes is lower than the Yangtze River's water level during the dry season. Conversely, the water level of the main stream exceeds that of both the floodplain and the lakes enclosed by the Jingjiang embankment. In the tidal reach, especially within the Taihu Lake basin, the basal elevation of lakes typically falls below sea level. Meanwhile, lakes located along the section from Chenglingji to Wuhu exhibit basal elevations that correspond with the Yangtze River's annual average and dry season water levels. Given the widespread presence of lakes along the middle and lower reaches of the Yangtze River, our study introduces a new proxy for reconstructing the mean water level of the mid-lower Yangtze River in the Holocene. By analyzing sediments from Nanyi Lake and Chenyao Lake in the lower Yangtze River, we attempted to reconstruct the water level of the Yangtze River's main channel since 8 ka BP. [ABSTRACT FROM AUTHOR]

As one of the key materials used in the civil engineering industry, concrete has a global annual consumption of approximately 10 billion tons. Cement and fine aggregate are the main raw materials of concrete, and their production causes certain harm to the environment. As one of the countries with the largest production of industrial solid waste, China needs to handle solid waste properly. Researchers have proposed to use them as raw materials for concrete. In this paper, the effects of different lithium slag (LS) contents (0%, 10%, 20%, 40%) and different substitution rates of recycled fine aggregates (RFA) (0%, 10%, 20%, 30%) on the axial compressive strength and stress-strain curve of concrete are discussed. The results show that the axial compressive strength, elastic modulus, and peak strain of concrete can increase first and then decrease when LS is added, and the optimal is reached when the LS content is 20%. With the increase of the substitution rate of RFA, the axial compressive strength and elastic modulus of concrete decrease, but the peak strain increases. The appropriate amount of LS can make up for the mechanical defects caused by the addition of RFA to concrete. Based on the test data, the stress-strain curve relationship of lithium slag recycled fine aggregate concrete is proposed, which has a high degree of agreement compared with the test results, which can provide a reference for practical engineering applications. In this study, LS and RFA are innovatively applied to concrete, which provides a new way for the harmless utilization of solid waste and is of great significance for the control of environmental pollution and resource reuse. [ABSTRACT FROM AUTHOR]

Background: Dissolved organic matter (DOM) is the most active component of soil organic matter (SOM), playing a major role in regulating soil fertility and carbon cycling. However, the effects of different wolfberry (Lycium barbarum L.) planting ages on the chemical diversity of DOM and its interaction with soil physicochemical properties have not been comprehensively studied. In this context, we collected soil samples (0–10 cm) from wolfberry orchards at different planting ages (1, 4, 6, 10, and 13 years) and from a corn field (0 years) in the arid region of Northwest Ningxia in China to assess the changes in soil DOM quantity and quality using ultraviolet–visible absorbance, fluorescence spectroscopy, and parallel factor analysis. Results: We found that the ages of the wolfberry plantation changed the contents of soil nutrients and SOM. In addition, significantly higher DOM concentrations were observed at wolfberry planting ages of 10 and 13 years than those in the control group (0 years) by 176.6 and 190.2%, respectively. The specific ultraviolet absorbance at 254 nm (SUVA254) and 254 nm to 365 nm ultraviolet absorbance ratio (E2/E3) values were decreased and increased, respectively, after wolfberry planting, indicating low aromatic and molecular weight compounds of soil DOM. The biogenic index (BIX) and fluorescence index (FI) of soil DOM ranged from 0.6 to 0.7 and 1.42 to 1.93, respectively, suggesting a combination of allochthonous and autochthonous sources. The short- and long-term wolfberry cultivations of 1 and 4 years decreased and increased the humification degrees of soil DOM, respectively. The contribution rate of the protein-like (C1) fluorescence intensity decreased, while that of the fulvic acid-like component (C3) increased with increasing wolfberry planting age, suggesting a change in the structure of soil DOM from protein-like to fulvic acids. In this study, total nitrogen (TN) and exchangeable Ca2+ were the main factors affecting the quantity and quality of soil DOM in the wolfberry orchards with different planting ages. Conclusions: This study demonstrated that long-term wolfberry plantation enhances the accumulation of soil DOM and more complex compounds, thereby promoting soil organic carbon sequestration under different planting ages and land-use types in terrestrial ecosystems. Highlights: Plantation age of wolfberry influenced the quantity and chemical composition of soil DOM. Long-term wolfberry plantation (more than 10 years) significantly enhanced the DOM content. The conversion of farmland to wolfberry forest decreased the aromaticity and molecular weight of soil DOM. The fulvic acid-like substances become the main fluorescent components of soil DOM over time since wolfberry plantations. TN and exchangeable Ca2+ were the main factors affecting the quality of wolfberry soil DOM. [ABSTRACT FROM AUTHOR]

Dissolved organic matter (DOM) plays a critical role in ecosystem function and productivity, particularly in carbon (C) cycling in grassland ecosystems. However, changes in the structural complexity of DOM in a desert steppe following long‐term treatment with nitrogen (N) and phosphorus (P) remain unclear; this limits our understanding of the nutrient‐related soil C cycle in a desert steppe. In the present study, soil experiments were conducted in the 0–10 cm soil layer of a desert steppe in northern China from 2017 to 2021, and four treatments were established: P, N, N + P (NP), and no nutrient addition (CK). The content and chemical composition of soil DOM were determined by ultraviolet–visible absorbance, fluorescence, and Fourier transform infrared spectroscopy. Compared to CK treatment, nutrient addition increased soil DOM content by 2.86%–53.84%. NP addition increased the average molecular weight, aromaticity, and humification degree of soil DOM. The DOM source was attributed to the combination of foreign and local sources. Fluorescent components of the DOM samples were mainly proteins and humic acids; the humic acid content decreased after N addition and increased after P and NP addition. Nutrient availability and pH were the key factors affecting the changes in the source and average molecular weight of the DOM, respectively. The soil organic matter content was significantly positively correlated with the humification index (r = 0.96). These results imply that nutrient addition accelerates the accumulation of DOM and influences its structural complexity; this potentially benefits soil C sequestration in a desert steppe. [ABSTRACT FROM AUTHOR]

Investigating the impacts of climatic factors and human activities on sedimentary records of heavy metal (HM) contamination in lakes is essential for decision-making in global environmental monitoring and assessment. Spatiotemporal distributions of grain size (GS) and HM (Al, Cr, Mn, Ni, Cu, Zn, As, and Pb) concentrations have been conducted in core sediments that are collected from two adjacent plateau fault-bound lakes in southwest China with contrasting environments, i.e., deep oligotrophic Lake Fuxian (FX) and shallow hypertrophic Lake Xingyun (XY). Results showed that the average value of d50 in FX (4.61 μm) was lower than that in XY (8.35 μm), but the average concentrations of HMs (except Cr and Mn) in XY were higher than those in FX. Heavy metal burial rates (HMBR) were mainly controlled by sediment accumulation rates (SARs) rather than HM concentrations. The correlation coefficients between GS and HM concentrations became strong as the increasing water depths were associated with a stable sedimentary environment. Time-integrated enrichment factors (EF) and source identification of HMs between FX and XY represented that Cr, Ni, and Cu originated from natural sources but Mn, Zn, As, and Pb from anthropogenic sources, respectively. Regardless of FX and XY, the transition times of HMs from natural to anthropogenic sources occurred in the mid-1960s. Comparison of qualification impacts of climatic factors and human-induced factors on increased anthropogenic HMBR by the partial least squares path modeling (PLS-PM) implied that socio-economic activities, such as population density (PD) and gross domestic product (GDP), provided higher contributors to increased anthropogenic HMBR in XY (0.23/0.71) than FX (0.11/0.18). The comparative results of this study provided new insights into environmental monitoring and management of HM contamination for adjacent lakes with contrasting environments. [ABSTRACT FROM AUTHOR]

Different land use and management actions can affect soil aggregates (SAs) and nutrient stocks, which are crucial for sustainable agriculture. The impacts of various chrono‐sequences on the soil aggregate structure, soil organic carbon (SOC) and nutrients associated with aggregate fractions in wolfberry (Lycium barbarum L.) plantations are still not fully understood. This study examined the composition and stability of SAs, SOC, total nitrogen (TN), available phosphorus (AP) and exchangeable cations (K+, Na+, Ca2+ and Mg2+) in bulk soil and various aggregate‐size fractions from five wolfberry plantations with varying ages (1, 4, 6, 10 and 13 years) and a corn field (0 years) in the arid region of northwest Ningxia in China. The results indicated that silt–clay (<53 μm) fractions were dominant in the soil, accounting for 51%–66%, under different plantation ages. The proportion of the macro‐aggregates (>250 μm) increased significantly, by 40%–47%, over the 4 years of wolfberry plantation. Likewise, the soil aggregate stability was improved, and total exchangeable bases (TEB) along with numerous cations concentrations (K+, Na+, Ca2+ and Mg2+) in SAs were significantly reduced as the wolfberry plantings became older. Both concentrations of SOC and TN in the soil aggregates peaked in the 13th year. The silt–clay fractions stored a considerable amount of SOC and nutrients. However, short‐term (under 6 years) cultivation of wolfberry reduced the stocks of SOC, TN and AP in the soil, while long‐term (over 10 years) cultivation increased them, particularly in macro‐aggregates. These findings indicated that long‐term wolfberry farming had several advantages, such as enhancing soil structure, accumulating SOC and nutrients and ameliorating alkaline soils, especially after 10 years, in the arid northwest of China. [ABSTRACT FROM AUTHOR]

A bs tract: Climate change and anthropogenic activities mutually degraded global lake ecosystems during the Anthropocene. Nutrient mitigation via catchment management has been a constant priority for lake ecological restoration; however, the outcomes after mitigation remain uncertain. In particular, there is limited knowledge on the effects of large‐scale forest restoration and soil erosion reduction in catchments on the ecological dynamics of downstream aquatic systems.Here, we study a strategically chosen alpine lake from the Loess Plateau in northern China, which has been extensively afforested in the past decades. We present high‐resolution, multi‐proxy records to reconstruct environmental and ecological dynamics since 1960. To quantify the potential mechanisms, we combined evidence from palaeolimnological records, contemporary field observations and process‐based ecosystem modelling. We developed palaeorecord‐based proxies for water transparency, nutrient concentrations and algal composition, and applied these proxies to ecosystem modelling.Our results show that despite the concurrent decline in nutrient levels, the lake ecosystem has experienced large‐magnitude rapid shifts since 2000, characterised by unambiguously increased algae proliferation and community changes. The modelling results revealed that the reduction in soil erosion acts as a "double‐edged sword"; that is, lower external nutrient loading via soil erosion is ideal for in‐lake algae inhibition, whereas increasing light availability counteracts the reduced yet still sufficient nutrient concentrations and, ultimately, promotes temporary algal proliferation via extended habitats and intensive photosynthesis. Intriguingly, lake warming plays a secondary role in driving these ecological dynamics.Our results emphasised the unexpected algal proliferation when the nutrient level declined in lake ecosystems; thus, other compound factors, including water transparency and climate warming, need to be incorporated for reliable prediction and effective restoration. A multi‐disciplinary approach integrating palaeorecords as ecological indicators and process‐based ecosystem modelling holds great potential for investigating long‐term lake ecological dynamics in the context of rapid global changes. [ABSTRACT FROM AUTHOR]

Overpressure is significant to the exploration and exploitation of petroleum due to its influence on hydrocarbon accumulation and drilling strategies. The deep-burial hydrocarbon reservoirs of Jurassic strata in the central Junggar Basin are characterized by intensive overpressure, whose origins are complex and still unclear. In this study, Bowers' method and sonic velocity-density crossplot method based on well logging data were used as a combination for overpressure judgements in geophysics. Furthermore, the corresponding geological processes were analysed in quality and quantity to provide a rational comprehension of the overpressure origins and the model of overpressure evolution and hydrocarbon accumulation processes. The results showed that hydrocarbon generation in the Jurassic source rocks led to overpressure in the mudstones, while hydrocarbon generation in Permian source rocks led to overpressure in the sandstone reservoirs in Jurassic strata by vertical pressure transfer. The burial and thermal history indicated that the aquathermal effect of pore fluids by temperature increase in deep strata is also an important origin of overpressure, while disequilibrium compaction may not be the dominant cause for the overpressure in deep-buried strata. Furthermore, the continuous tectonic compression in both the north--south and west-east trends from the Jurassic period to the present may also have enhanced the overpressure in deep strata. Meanwhile, the developed faults formed by intensive tectonic compression led to pressure transfer from source rocks to the Jurassic reservoirs. Overpressured geofluids with hydrocarbons migrated to sandstone reservoirs and aggravated the overpressure in the Jurassic strata. To conclude, the intensive overpressure in the central Junggar Basin is attributed to the combination of multiple mechanisms, including hydrocarbon generation, the aquathermal effect, tectonic compression and pressure transfer. Furthermore, the developed overpressure indicated hydrocarbon migration and accumulation processes and the potential of oil and gas reservoirs in deeply buried strata. We hope this study will provide a systematic research concept for overpressure origin analysis and provide guidance for petroleum exploration and exploitation in deep-buried strata. [ABSTRACT FROM AUTHOR]

Objective: To derive the Chinese medicine (CM) syndrome classification and subgroup syndrome characteristics of ischemic stroke patients. Methods: By extracting the CM clinical electronic medical records (EMRs) of 7,170 hospitalized patients with ischemic stroke from 2016 to 2018 at Weifang Hospital of Traditional Chinese Medicine, Shandong Province, China, a patient similarity network (PSN) was constructed based on the symptomatic phenotype of the patients. Thereafter the efficient community detection method BGLL was used to identify subgroups of patients. Finally, subgroups with a large number of cases were selected to analyze the specific manifestations of clinical symptoms and CM syndromes in each subgroup. Results: Seven main subgroups of patients with specific symptom characteristics were identified, including M3, M2, M1, M5, M0, M29 and M4. M3 and M0 subgroups had prominent posterior circulatory symptoms, while M3 was associated with autonomic disorders, and M4 manifested as anxiety; M2 and M4 had motor and motor coordination disorders; M1 had sensory disorders; M5 had more obvious lung infections; M29 had a disorder of consciousness. The specificity of CM syndromes of each subgroup was as follows. M3, M2, M1, M0, M29 and M4 all had the same syndrome as wind phlegm pattern; M3 and M0 both showed hyperactivity of Gan (Liver) yang pattern; M2 and M29 had similar syndromes, which corresponded to intertwined phlegm and blood stasis pattern and phlegm-stasis obstructing meridians pattern, respectively. The manifestations of CM syndromes often appeared in a combination of 2 or more syndrome elements. The most common combination of these 7 subgroups was wind-phlegm. The 7 subgroups of CM syndrome elements were specifically manifested as pathogenic wind, pathogenic phlegm, and deficiency pathogens. Conclusions: There were 7 main symptom similarity-based subgroups in ischemic stroke patients, and their specific characteristics were obvious. The main syndromes were wind phlegm pattern and hyperactivity of Gan yang pattern. [ABSTRACT FROM AUTHOR]

Nitrogen and phosphorus can influence the stability of soil organic matter (SOM) and aggregate, which are important for ecosystem functions. However, understanding remains limited regarding the impact of nutrient addition on soil aggregate stability, aggregate‐relevant organic matter and nutrients in desert steppe. Here, we studied the variation of soil aggregate stability, nutrients, and the exchangeable cations distribution characteristics, and the chemical composition and thermal stability of SOM were analyzed using thermogravimetric (TG) and Fourier transformed infrared spectroscopy. Samples of soil were collected under four conditions, phosphorus addition (P), nitrogen addition (N), combined phosphorus and nitrogen addition (NP), and no addition (CK), from 0 to 10 cm depth over 4‐year experiments in desert steppe in northern China. The percentage of micro‐aggregates (0.25–0.053 mm) and large macroaggregates (>2 mm) dramatically increased by 34.2% and 18.1%, respectively, under the N treatment condition compared to the CK treatment, and micro‐aggregate content significantly increased under the P treatment, respectively. Nitrogen addition significantly increased the soil aggregate stability index, but the P addition reduced their value. The both macro‐aggregates (>0.25 mm) and silt‐clay (<0.053 mm) were preferentially enriched with soil nutrients and the exchangeable cations. The N and P addition was beneficial to nutrients accumulating in macro‐aggregates, and enhanced the aliphatic‐C and aromatic‐C abundances respectively. The TG‐T50 value (i.e., temperature when 50% of SOM is lost) increased after nutrient addition, indicating that the SOM has higher thermal stability, especially in the micro‐aggregates. The addition of N may have potentially a greater influence on aggregate stability through their influence exchangeable polyvalent cations (Ca2+ and Mg2+), and stability of SOM was influenced by chemical composition and exchangeable K+, Na+, Ca2+ contents in desert steppe. Overall, nutrient addition effects stability of SOM and aggregate by altering chemical composition and exchangeable cations in desert steppe in northern China. [ABSTRACT FROM AUTHOR]

Purpose: Green manure plays a key role in reducing chemical fertilizer applications and increasing soil organic carbon (SOC) stock. The effects of chemical fertilizer substitution by Chinese milk vetch (MV) on the distribution and composition of organic carbon fractions in macroaggregates and microaggregates and SOC stability mechanism were investigated in paddy soils in southern China. Methods: A 10-year (2008–2018) field experiment was conducted, including no fertilizer (CK), 100% NPK fertilizer (F100), MV with different percentages of chemical fertilizer (MV + F100, MV + F80, MV + F60 and MV + F40). The soil was separated into distinct organic carbon fractions using aggregate density fractionation and SOC chemical structure was analyzed by fourier-transform infrared and nuclear magnetic resonance. Results: Chemical fertilizer substitution by MV increased SOC contents in the bulk soil by 9.1% (MV + F80), 5.8% (MV + F60), 17.9% (MV + F40) compared to F100. Organic carbon fraction mainly existed in mineral associated organic carbon (mSOC), accounting for 70.3–83.7% and 69.4–84.0% of the relative mass of macroaggregates and microaggregates, respectively. Compared to F100, aromatic C increased by 11.6% and 29.1% under MV + F60 within mSOC in macroaggregates and microaggregates. Within the mSOC in macroaggregates, compared to CK, MV + F80 and MV + F60 promoted the proportion of alkyl C by 9.6% and 6.7%, and decreased the content of O-alkyl C by 14.1% and 11.0%, respectively, which correspondingly increased alkyl C/O-alkyl C ratio. Conclusions: Substitution of chemical fertilizer by MV (especially MV + F80 and MV + F60) improved the stability of SOC via increasing recalcitrant structure in mSOC, and was conducive to the sequestration of SOC in paddy soils. [ABSTRACT FROM AUTHOR]

The influence of reactive nitrogen (N) and phosphorus (P) supplementation on ecosystem dynamics of soil organic matter (SOM) shows extensive variations. The underlying mechanisms of regulation of the chemical composition and dynamics of different SOM density fractions (DFs) in aggregates in a desert steppe by N and P supplementation are unclear. Here, the chemical composition and organic carbon (C) and N dynamics of various SOM DFs under N and P addition were assessed. Surface soil samples taken at 0–10 cm depth were obtained from 4-year (2017–2021) experiments under four conditions, namely N treatment, P treatment, combined N and P treatment (NP), and no nutrient supplementation (CK), in a desert steppe located in northern China. Nutrient supplementation significantly increased (P < 0.05) SOM content by 8.89–35.4%; however, the total N content remained constant. N addition mainly increased SOM content in the macroaggregates (>0.25 mm), while P enhanced SOM in microaggregates (0.25–0.053 mm) and silt-clay (<0.053 mm). The fine particulate organic matter (fPOM) proportion was increased significantly (P < 0.05) by 18.4% and 16.4% in macro- and microaggregates under N addition, respectively; P addition mainly enhanced mineral-associated SOM (mSOM) proportion in aggregates. N supplementation remarkably enhanced (P < 0.05) fPOM's organic C content by 27.3% and 32.0%, and N content by 40.9% and 145.7% in macro- and microaggregates, respectively. Single N and P addition promoted the enrichment of labile and resistant organic components in light fraction (LF), respectively. N promoted the enrichment of stable organic components in the mSOM of microaggregates. Nutrient inputs drive mSOM formation through the interaction of carboxyl-C and mineral surface. Based on a stronger δ13C and δ15N signal, N addition enhanced SOM decomposition in aggregates. Nutrient supplementation promoted SOM accumulation through the formation of more stable old C in POM and silt-clay. Our findings suggest that SOM accumulation in desert steppe probably increases following nutrient addition, but the mechanism is different through which N or P enrichment affects soil dynamics and chemical composition of SOM DFs in desert steppe. • The proportion of fPOM and mSOM were increased under N and P addition, respectively. • N supplementation can promote the accumulation of fPOM fractions with C and N in macroaggregates. • Supplementation with P and N enriched labile and resistant organic components in light fraction, respectively. • Nutrient input drives the formation of mSOM by the interaction of carboxyl-C and mineral surface. • Nutrient addition promoted accumulation of SOM by forming more stable old C in POM and silt-clay [ABSTRACT FROM AUTHOR]

Sustainability is an imperative goal for developing public–private partnership (PPP) projects, which are largely affected by policies. However, few studies have explored the impact of policy implementation on the sustainable development of PPP projects. This study examines the impacts of PPP policy implementation on PPP sustainability by conducting a comprehensive analysis that is grounded in a proposed stakeholder-based framework of the PPP policy implementation process. Critical factors are identified through exploratory factor analysis (EFA) of 275 survey responses from PPP practitioners in China. Subsequently, ordinary least squares (OLS) regression analysis is used to examine the effects of policy implementation on project sustainability in PPPs. The results reveal five factors that can explain the construct of PPP policy implementation, namely, the implementing organization's capacity (F1), policy quality and resources (F2), the environment (F3), the involvement of the target group (F4), and the sustainability of the PPP projects (F5). F1, F3, and F4 have significant positive impacts on PPP sustainability, which is measured in terms of its economic, social, and environmental dimensions. [ABSTRACT FROM AUTHOR]

Antibiotic resistance genes (ARGs) have become an important public health problem. In this study, we used metagenomic sequencing to analyze the composition of ARGs in selected original habitats of northeast China, comprising three different rivers and riverbank soils of the Heilongjiang River, Tumen River, and Yalu River. Twenty types of ARG were detected in the water samples. The major ARGs were multidrug resistance genes, at approximately 0.5 copies/16S rRNA, accounting for 57.5% of the total ARG abundance. The abundance of multidrug, bacitracin, beta-lactam, macrolide-lincosamide-streptogramin, sulfonamide, fosmidomycin, and polymyxin resistance genes covered 96.9% of the total ARG abundance. No significant ecological boundary of ARG diversity was observed. The compositions of the resistance genes in the three rivers were very similar to each other, and 92.1% of ARG subtypes were shared by all water samples. Except for vancomycin resistance genes, almost all ARGs in riverbank soils were detected in the river water. About 31.05% ARGs were carried by Pseudomonas. Opportunistic pathogenic bacteria carrying resistance genes were mainly related to diarrhea and respiratory infections. Multidrug and beta-lactam resistance genes correlated positively with mobile genetic elements (MGEs), indicating a potential risk of diffusion. The composition of ARGs in three different rivers was similar, indicating that climate plays an important role in ARG occurrence. ARG subtypes in river water were almost completely the same as those in riverbank soil. ARGs had no significant geographical distribution characteristics. Many ARGs were carried by human pathogenic bacteria related to diarrhea and respiratory infections, such as Pseudomonas aeruginosa and Aeromonas caviae. In general, our results provide a valuable dataset of river water ARG distribution in northeast China. The related ecological and geographical distribution characteristics should be further explored. [ABSTRACT FROM AUTHOR]

As part of China's first Mars exploration mission 'Tianwen-1', the Zhurong rover has successfully touched down on the surface of southern Utopia Planitia on May 15th 2021 and has been conducting surface operations for several months. A multispectral camera (MSCam), as an important payload onboard the Zhurong rover, aims to acquire multispectral images to investigate the morphological characteristics and mineralogic properties of the Martian surface. In this study, a detailed optimization design for the MSCam was carried out to achieve the abovementioned scientific objectives. The MSCam can perform multispectral imaging without chromatic aberration by utilizing eight narrow bandwidth filters made of glass of different thicknesses. Clear images of observation targets at different distances can be obtained by utilizing the six focal plane compensation lenses of varying thicknesses through the rotation of wheels. Calibration experiments, key specification tests and ground verification tests were also conducted in this study. Our results show that the pixel resolution of the MSCam can reach 0.146 mrad, the system static modulation transfer function (MTF) of the MSCam is better than 0.25@525 nm, and the signal-to-noise ratio (SNR) is higher than 40 dB, all of which allow clear imaging and accurate multispectral data acquisition of the targets. The high-resolution images obtained by the MSCam will provide detailed geological context for the data interpretation of other payloads on the rover, such as the Mars surface composition detector (MarSCoDe). The mineralogy information of the targets (e.g., fresh rock, dune) indicated by the MSCam multispectral data will also help to constrain the surface material composition of Mars. [ABSTRACT FROM AUTHOR]

Background: Sugammadex reverses neuromuscular blockade induced by steroidal relaxants. We compared the recovery for neuromuscular blockade reversal with sugammadex in children aged 1–12 years. Methods: From August 2019 to August 2020, patients who received 2.0 mg·kg− 1 sugammadex for neuromuscular blockade reversal after surgery were recruited. The primary outcome was the time for the train-of-four ratio (TOFR) to recover to 0.9; secondary outcomes included the incidence of the TOFR < 0.9, extubation time, length of stay at the post-anesthesia care unit, and adverse events. Hemodynamic parameters before and 5 min after sugammadex administration and vital signs in the recovery room were also recorded. Results: Eighty-six children were recruited (1 to < 3 years, n = 23; 3 to < 5 years, n = 33; 5 to ≤12 years, n = 30). Intergroup differences in the recovery of the TOFR to 0.9 were not statistically significant (F = 0.691, p = 0.504). Recurrence of the TOFR < 0.9 was not observed in any group. Five minutes after sugammadex administration, the heart rates of patients aged 3 to < 5 and 5 to ≤12 years were significantly lower than those at baseline (p < 0.05). Extubation time was similar in patients aged 1 to ≤12 years. Length of stay and end-tidal capnography at the post-anesthesia care unit as well as adverse events did not differ significantly. Conclusion: A moderate (TOF count two) rocuronium-induced neuromuscular blockade can be effectively and similarly reversed with sugammadex 2 mg·kg− 1 in Chinese children aged 1–12 years. Trial registration: Chinese Clinical Trial Registry: ChiCTR1900023715 (June 8, 2019). [ABSTRACT FROM AUTHOR]

Background: The objective of this study was to detect the urinary levels of dimethoate, benzo(a) pyrene (BaP), and bisphenol A (BPA) in first-year Hohai University students with different geographic origins.Methods: First-morning urine samples were collected from 540 healthy freshmen aged 17 to 19 years. Chemical levels were measured using β-glucuronidase hydrolysis followed by a high-performance liquid chromatography-tandem mass spectrometry-based method. Geometric means (GMs) of these three chemicals are presented by body mass index (BMI) and location in a volume-based and creatinine-standardized way.Results: GM concentrations of omethoate, BPA and 3-OHBaP were 9.47 μg/L (10.80 μg/g creatinine), 3.54 μg/L (4.04 μg/g creatinine) and 0.34 ng/L (0.39 ng/g creatinine), respectively. The GM concentration of omethoate in males was significantly higher than that in females. The individuals with a BMI higher than 23.9 had higher GM concentrations of omethoate, BPA, and 3-OHBaP. The inhabitants of Southwest China had significantly lower GM concentrations of omethoate, BPA, and 3-OHBaP than those who lived in other locations in China.Conclusion: The average level of environmental chemical accumulation in freshmen is lower in Southwest China and differs in youth who live in different regions. In addition, obesity is correlated with higher toxin levels in youth. [ABSTRACT FROM AUTHOR]

Non-typhoidal Salmonella (NTS) is a common cause for self-limiting gastroenteritis, representing a public health concern globally. NTS is one of the leading causes of foodborne illnesses in China; however, the invasive infection caused by NTS is largely underappreciated. Here, we reported an NTS invasive infection caused by an infrequently reported serovar Telelkebir (13,23:d:e,n,z15) strain FJ001 in China, which carries antimicrobial-resistant genes [ fosA7 and aac(6′)-Iaa ] and typhoid-toxin genes (cdtB , pltA , and pltB). By conducting the whole genomic sequencing, we also investigated the relatedness of this strain with an additional 120 global contextual Salmonella enterica serovar Telelkebir (S. Telelkebir) isolates, and assessed the antimicrobial-resistant determinants and key virulence factors using the available genomic dataset. Notably, all 121 (100%) of the S. Telelkebir strains possessed the typhoid toxin genes cdtB , pltA , and pltB , and 58.67% (71/121) of S. Telelkebir harbored antimicrobial-resistant gene fosaA7. The study by core genome multilocus sequence typing (cgMLST) and core single-nucleotide polymorphism (SNP)-based phylogenomic analysis demonstrated that the S. Telelkebir isolates from different sources and locations clustered together. This suggests that regular international travels might increase the likelihood of rapid and extensive transmissions of potentially pathogenic bacteria. For the first time, our study revealed the antimicrobial resistance, virulence patterns, and genetic diversity of the serovar S. Telelkebir isolate in humans and similar isolates over the world. The present study also suggests that genomic investigation can facilitate surveillance and could offer added knowledge of a previously unknown threat with the unique combination of virulent and antimicrobial-resistant determinants. [ABSTRACT FROM AUTHOR]

Lake Hulun is the fifth‐largest lake in China, playing a substantial role in maintaining the balance of the grassland ecosystem of the Mongolia Plateau, which is a crucial ecological barrier in North China. To better understand the changing characteristics of Lake Hulun and the driving mechanisms, it is necessary to investigate the water storage changes of Lake Hulun on extended timescales. The main objective of this study is to reconstruct the water storage time series of Lake Hulun over the past century. We employed a machine learning approach termed the extreme gradient boosting tree (XGBoost) to reconstruct the water storage changes over a one‐century timescale based on the generated bathymetry and satellite altimetry data and investigated the relationships with hydrological and climatic variables in long term. Results show that the water storage changes from 1961 to 2019 were featured by four fluctuation phases, with the highest water storage observed in 1991 (14.02 Gt) and the lowest point in 2012 (5.18 Gt). The century‐scale reconstruction result reveals that the water storage of Lake Hulun reached the highest point in the 1960s within the period of 1910–2019. The lowest stage occurred in the sub‐period of the 1930s–1940s, which was even lower than the alerted shrinkage stage in 2012. The predictive model results indicate the effective performance of the XGBoost model in reconstructing century‐scale water storage variations, with the mean absolute error of 0.68, normalized root mean square error of 0.11, Nash–Sutcliffe efficiency of 0.97, and correlation coefficient of 0.94. The annual fluctuations of water storage were mostly affected by precipitation, followed by vapor pressure, temperature, potential evapotranspiration, and wet day frequency. The dominating characteristics of different variables vary evidently with different sub‐periods. The atmospheric circulations of the Arctic Oscillation, El Nino Southern Oscillation, Pacific Decadal Oscillation, and North Atlantic Oscillation have tight associations with the water storage variations of Lake Hulun, which change with different study periods. Plain Language Sumamry: To better understand the changing characteristics of Lake Hulun and the driving mechanisms, it is necessary to investigate the water storage changes of Lake Hulun on extended timescales (e.g., century timescale). The main objective of this study is to reconstruct the water storage time series of Lake Hulun over the past one century. We employed a machine learning approach termed the extreme gradient boosting tree (XGBoost) to reconstruct the one‐century water storage changes and investigated the relationships with hydrological and climatic variables in long term. The century‐scale reconstruction result reveals that the water storage reached the highest point in the 1960s within the period 1910‐2019. The lowest stage occurred in the 1930s‐1940s, which was even lower than the alarted shrinkage stage in 2012. The annual fluctuations of water storage were mostly affected by precipitation, followed by vapor pressure, wet day frequency, potential evapotranspiration, and temperature. However, the dominating characteristics of different variables vary evidently with different sub‐periods. This study is expected to provide an efficient technical solution of reconstructing long‐term lake water storage records and to advance our scientific understanding of the characteristics of lake water balances in response to climate change and variability in the Mongolia Plateau. Key Points: The complete bathymetry map of Lake Hulun was constructed based multi‐source remote sensing dataA machine learning approach was employed to reconstruct the century‐scale water storage of Lake HulunThe potential links of one‐century variations of lake water storage with climatic variables and atmospheric circulations [ABSTRACT FROM AUTHOR]

Soil organic matter stored in soil aggregate fractions is a major soil organic carbon (SOC) stabilization process. The distribution of SOC within soil aggregate fractions and their association with SOC chemical compounds in the agroecosystem is not well understood. Our long‐term study (6 and 9 years) in central China examined the effects of tillage and straw management practices on chemical functional components of SOC, SOC contents of soil aggregates, and the relationship of the SOC composition with aggregate‐associated C in a rice‐rape cropping system. The soil samples from 2 sites were separated into six aggregate classes (>5, 5–2, 2–1, 1–0.5, 0.5–0.25, and <0.25 mm) by a wet‐sieving method. Chemical composition of SOC was assessed by CPMAS 13C NMR, FTIR and SEM techniques. Among all chemical components of the SOC, O‐alkyl C was the most important C type, which increased (about 54–110%) at both our sites, although aromatic C increased (about 30%) and carbonyl C decreased at one site ‐ Jingzhou after straw was returned. While, aromatic, carboxylic, aliphatic and amide components were stabilized after straw return. Alkyl C and O‐alkyl C ratio were enhanced after straw return but the aromaticity index and hydrophobicity index altered in the studied sites. Among all defined aggregates, approximately 10–18% of SOC was stored in >5 mm, 5–2 mm, 2–1 mm aggregates and 5–10% was stored in other aggregate fractions (1–0.5 mm, 0.5–0.25 mm and <0.25 mm) after straw return. SOC Chemical components were positively and negatively correlated with aggregate‐associated C fractions. This study concluded that straw management improved the chemical composition of SOC and increased the SOC contents of bulk soil as well as helped store more organic matter in macroaggregates. [ABSTRACT FROM AUTHOR]

Background: Atrial fibrillation (AF) is a common arrhythmia, which is closely related to cardiovascular morbidity and mortality. Although acupuncture is used in the treatment of AF, the evidence is insufficient. The objective of this pilot trial is to evaluate the feasibility, preliminary efficacy, and safety of acupuncture in reducing AF burden for persistent AF after catheter ablation (CA).Methods and Design: This will be a multi-center, 3-arm, pilot randomized controlled trial in China. Sixty patients in total will be randomly assigned to the specific acupoints group, the non-specific acupoints group, or the non-acupoints group in a 1:1:1 ratio. The whole study period is 6 months, including a 3-month treatment period and a 3-month follow-up period. All patients will receive 18 sessions of acupuncture over 12 weeks after CA and appropriate post-ablation routine treatment. The primary outcome is AF burden at 6 months after CA measured by electrocardiography patch that can carry out a 7-day continuous ambulatory electrocardiographic monitoring. The secondary outcomes include AF burden at 3  months after CA, recurrence of AF, quality of life, etc. The adverse events will also be recorded.Discussion: This pilot study will contribute to evaluating the feasibility, preliminary efficacy, and safety of acupuncture in reducing AF burden for persistent AF after CA. The results will be used for the sample size calculation of a subsequent large-scale trial.Trial Registration: Chinese Clinical Trial Registry ChiCTR2000030576 . Registered on 7 March 2020. [ABSTRACT FROM AUTHOR]

The East Asian monsoon (EAM) has experienced significant changes over the past 10,000 years that influenced East Asian agricultural development. However, the magnitude and extent of the EAM precipitation fluctuations at 6 ka remain unresolved, owing to uncertainty in individual lake records and substantial variations in the expansion limits in simulations of the mid-Holocene EAM precipitation. Here we present an approach based on multiple lake-level records using the "1D lake level—2D lake area—3D catchment hydrology" model to reconstruct the precipitation patterns in northern China, and to further quantify the extent of the EAM precipitation expansion in the mid-Holocene relative to today. The precipitation reconstructions suggest an ~550–1100 km northward expansion and an ~530–840 km westward migration of the EAM at 6 ka. At that time, the EAM precipitation domain covered over 6 million square kilometers. Thus, this approach mitigates the uncertainty and arbitrariness of reconstructions of the limit of the EAM precipitation fields and provides a benchmark for future climate modeling studies. [ABSTRACT FROM AUTHOR]

Purpose: Sleep disturbances are common in cancer patients, but little is known about preoperative insomnia and its associated factors in colorectal cancer (CRC) patients. The aim of this study was to clarify the relationship between preoperative insomnia and its associated factors (i.e., pain, anxiety, self-esteem, and coping styles) in CRC patients.Methods: A cross-sectional study was conducted in consecutive CRC inpatients (N = 434), who were required to complete the questionnaires about insomnia, pain, anxiety, self-esteem, and coping styles (acceptance/resignation, confrontation, avoidance) before the day of surgery. Hierarchical regression analyses were conducted to explore the relationships between preoperative anxiety and its associated factors.Results: Based on the cutoff value of Athens Insomnia Scale (scores ≥ 6) in Chinese cancer patients, the prevalence of insomnia was 38.2% before surgery. Pain (β = 0.087, p = 0.015) and anxiety (β = 0.372, p < 0.001) were positively associated with preoperative insomnia, while self-esteem (β = - 0.479, p < 0.001) and confrontation coping (β = - 0.124, p = 0.003) showed protective effects on preoperative insomnia when putting them together into hierarchical regression. The associated factors together accounted for an additional variance of preoperative insomnia (47.6%).Conclusions: In line with previous findings, the detrimental effects of pain and anxiety on preoperative insomnia were also observed in our study. More importantly, our main new findings were that self-esteem and confrontation coping played important roles in alleviating preoperative insomnia among CRC patients. Clinicians should take these results into account when developing cancer care management to relieve preoperative insomnia. [ABSTRACT FROM AUTHOR]

In the last several years, the massive success of the Fuling shale gas field in south‐western China has shown great potential in finding giant shale gas fields in the Upper Yangtze area, and it has also attracted the increasing attention from geologists to find more shale gas reservoirs around the world. However, there is still a great dispute as to whether the neighbouring Lower Yangtze area is a next potential shale gas block in China. In this study, we evaluate preliminarily the shale gas potentials of five important sets of marine shales based on systematic analyses for the sedimentary environment, thickness, total organic carbon (TOC), thermal maturity, and other organic geochemistry parameters of both geological records from outcrops and wells in the Lower Yangtze area. The first two sets of marine shales occur in the Lower Cambrian and the Ordovician, and they all are of over–high organic maturity due to strong effects from regional tectonic movements and thus have poor potential. Although the Lower Silurian shales are widely distributed in the Lower Yangtze region, a terrigenous delta, a low amount of organic matter (TOC < 1.2%), and late tectonic activity together created unfavourable conditions for the generation and accumulation of the Lower Silurian shale gas. The Permian black shales occur in the Middle and Upper Permian. Several proxies, such as the appropriate maturity (vitrinite reflectance Ro of approximately 2.0%), abundant organic matter (TOC of approximately 4 wt%), good total hydrocarbon potential (S1 + S2), and high level of hydrocarbon conversion have resulted in good conditions for shale gas generation. However, the relative thinness (only 30 m), severe tectonic modification, and regional cap rock are not favourable for shale gas preservation. The Lower Yangtze area therefore is not an excellent block for shale gas exploration compared to its neighbouring Upper Yangtze area. However, in some areas with less structural deformation, the possibility of finding shale gas reservoirs cannot be ruled out, especially for the Permian shales, which had a greater opportunity to generate and accumulate shale gas than the other marine shales. In addition, for new shale gas exploration breakthroughs in the future, structural studies are essential in offering better understanding of the preservation conditions in the Lower Yangtze area. [ABSTRACT FROM AUTHOR]

The Junggar Basin is a typical superimposed system characterized by multilateral steep thrusts and extrusions and one of the primary petroliferous basins in Western China. To date, geologists have been most interested in the basin's tectonic evolution and petroleum geology characteristics. Based on field outcrops, lithologic combinations, logging curves, and seismic reflection characteristics, we present a systematic study of the sequence stratigraphy pattern for the Jurassic central Junggar Basin. Herein, we identify the central Junggar area as having a "dual" characteristic sequence framework composed of a lowstand system tract (LST) and a transgressive system tract (TST), which is distinguishable from the traditional three system tract (LST, TST, and highstand system tract [HST]). In each third‐order sequence, the LST consists of conglomerate or pebbly sandstone deposits, displaying the characteristics of braided channel and fan delta. The TST consists of siltstone, argillaceous siltstone, and mudstone, displaying fine‐grained, shore‐shallow lacustrine deposits. It is considered that the combination of multiphasic thrust extrusion and subsequent, steady deposition is likely responsible for the dual‐system tract. The forming process of the dual‐system tract pattern could divide into four stages: the quiet stage of tectonic activity, the early stage of compression, the continuous stage of compression, and the rapid rebound stage. Additionally, two reservoir predictive models are proposed: the progradational predicting model on the edge of the depression and truncated and pinchout predicting model on the palaeo‐uplift. We conclude that the coarse clastic unit of the LST has bright prospects for oil and gas exploration within the superimposed system in Western China. [ABSTRACT FROM AUTHOR]

Purpose: Sediments are natural archives to record the occurrence and sources of organochlorine pesticides (OCPs). Most previous studies on historical occurrence and sources of OCPs in China only focused on DDTs and HCHs. Comprehensive knowledge of historical occurrence and sources of persistent OCPs in China are scarce. Materials and methods: One 20-cm sediment core was collected from the third largest freshwater lake (Lake Taihu) in China, then sliced every 1 cm, dated with 137Cs and 210Pb, and used for the analysis of 21 OCPs. Isomer ratios and principal component analysis (PCA) were applied to apportion the historical sources of the OCPs in this lake. Results and discussion: Three concentration peaks of OCPs were observed in the middle-late 1950s, early-middle 1980s, and the middle 2000s. The average concentration of ΣDDX was 238.55 ± 55.43 ng gdw−1 from 1948 to 2012. p,p′-DDT was the dominant congener of DDX, mostly derived from the legacy technical DDT. The average concentration of ΣHCHs, aldrin, heptachlor epoxide, endosulfan sulfate, methoxychlor, heptachlor, trans-chlordane, cis-chlordane, endosulfan I, endrin, diendrin, endosulfan II, diendrin aldehydrate, and diendrin ketone were 24.56 ± 6.90, 10.35 ± 3.26, 9.51 ± 1.88, 7.37 ± 1.81, 7.01 ± 2.82, 2.60 ± 0.81, 0.63 ± 0.24, 3.21 ± 1.25, 1.04 ± 0.29, 3.89 ± 2.61, 5.67 ± 1.59, 1.07 ± 0.19, 1.09 ± 0.22, and 1.32 ± 0.33 ng gdw−1. Conclusions: Dicofol and p,p′-DDT-containing anti-fouling paints may be responsible for the current input of p,p′-DDT. Most of the HCHs were derived from the legacy technical HCHs, but there was input of lindane as well. PCA indicated that the legacy technical DDTs, HCHs, heptachlor, chlordane, aldrin, and endrin, the current input of p,p′-DDT, methoxychlor, and endosulfan, and microbial transform of γ-HCH to α-HCH were the dominant sources for the 21 OCPs in Lake Taihu. [ABSTRACT FROM AUTHOR]

Shengjin Lake is a typical Yangtze River-connected lake, that is also a national nature reserve and a Wetland of International Importance. In order to evaluate the eco-environmental evolution of Shengjin Lake, a210Pb- and 137Cs-dated sediment core collected from the upper part of the lake was analyzed. Based on a biological indicator (subfossil cladoceran) and geochemical indicators (loss on ignition (LOI), total organic carbon (TOC), δ13C of bulk sediments (δ13C org), total phosphorous (TP) and total nitrogen (TN)), we revealed the changes in the cladoceran assemblages and eco-environmental processes of Shengjin Lake. The results showed that there was a healthy ecological environment with low nutrient levels in Shengjin Lake before the 1980s. However, the increasing levels of the eutrophic species B. longirostris , nutrients (TN and TP) and organic matters (LOI and TOC), and the decreasing δ13C org in recent decades indicated that the trophic state of Shengjin Lake has increased since the 1980s. This corresponded with increasing anthropogenic effects, including land reclamation, chemical fertilizer application, and sluice construction. In addition, the droppings of water birds also promoted increases in nutrient and organic matters levels in Shengjin Lake. [ABSTRACT FROM AUTHOR]

Lake sediments are important reservoirs for polycyclic aromatic hydrocarbons (PAHs) in catchments. Knowledge of occurrence, sources, and toxicological risk of PAHs is crucial to abate their pollution and risk. We investigated the spatial and temporal occurrence, sources, and potential toxicological risks of 12 PAHs in the surface sediments and one sediment core of the largest deep lake (Lake Fuxian) of China. Our results indicated the average ΣPAH12 in the surface sediments of this lake was 1550.6 ± 231.4 ng gdw−1, much higher than those of most Chinese shallow lakes. The average ΣPAH12 in the lake area was higher than that in the estuaries. The average ΣPAH12 in the estuaries of influent rivers was higher than that of the outlet river. Coal combustion, gasoline combustion, and diesel combustion were the major sources, which contributed 68.5%, 19.8%, and 11.8% to the ΣPAH12. The average total benzo[a]pyrene toxic equivalent concentration (TEQcarc) of the six most carcinogenic PAHs was 317.1 ± 86.3 ngTEQcarc g−1 in the surface sediments. The ΣPAH12 increased from 301.7 to 1964.4 ng gdw−1 from 1945 to 2011 and significantly increased with the GDP and population of the catchment. The contribution of coal combustion to the concentrations of PAHs increased gradually with time. The total TEQcarc, and the percentage of ΣPAHcarc to ΣPAH12 in the sediment core increased from 5.0 to 84.6 ngTEQcarc g−1 and from 5.7 to 23.3%, respectively. Our study highlights the importance of such deep waters in burying PAHs and the increasing risk of PAHs from human activities. [ABSTRACT FROM AUTHOR]

Lake level changes respond to variations in regional water balance and thus it has been one of the most important indicators applied to reconstruct paleoprecipitation and paleoclimate. In this study, the effective precipitation and the atmospheric circulation during the past three key periods, i.e., Last Interstadial (30 cal ka B.P.), the Last Glacial Maximum (LGM, 21 cal ka B.P.) and Mid-Holocene (6 cal ka B.P.), were analyzed based on the 76 lake-level records documented in the second version of Chinese Lake Status Data Base (CLSDB 2). The results indicated that the western part of China was characterized by elevated lake levels and expanded lake surfaces at 30 cal ka B.P., resulting from the strength of southwest monsoons. The high water stands appeared at 21 cal ka B.P. for lakes in western China were due to the enhanced intensities of Westerlies as well as the low evaporation, although the distribution extent of high lake-levels was reduced. For the period of Mid-Holocene, the lake stands of western China were relatively lower than those of the Last Interstadial and LGM, mainly as a result of shrunken Westerlies. Lake records from eastern China during the Last Interstadial and LGM were scarce, although there were a few reports showing higher or lower water stands compared to the present. A large number of high lake level records from eastern China were observed at the Mid-Holocene, which may be linked with the enhanced East-Asian summer monsoons. [ABSTRACT FROM AUTHOR]

Lakes are important source of atmospheric methane (CH4). Especially for large and shallow lakes, accurate CH4 emission budgets must consider the spatial and seasonal heterogeneity which characterize these ecosystems. CH4 concentrations in sediment and lake water and CH4 fluxes from sediment were analysed in selected open water areas of Lake Taihu, the third largest freshwater lake in China, to test the hypothesis that CH4 concentrations and fluxes differ both spatially and temporally in relation to biological and environmental features. The results showed that Lake Taihu was a source of CH4 throughout the year. The observed CH4 concentrations and fluxes were higher in the north-western and south-eastern areas of the lake, and lower in the central area. This spatial heterogeneity in methane emissions was mainly related to local organic matter content, plant characteristics, deposition rate and sediment features. Seasonally, CH4 showed stronger emissions in summer. These results suggest that the analysis of CH4 dynamics in shallow lakes should consider the habitat heterogeneity and the different sources of organic matter. Furthermore, the CH4 emission budget should at least include high and low temperature periods to decrease temporal bias. [ABSTRACT FROM AUTHOR]

To date effects of climate change on bioaccumulation and biomagnification of chemical pollutants in planktonic food webs have rarely been studied. Recruitments of plankton have shifted earlier due to global warming. Global warming and precipitation patterns are projected to shift seasonally. Whether and how the shifts in plankton phenology induced by climate change will impact bioaccumulation and biomagnification of chemical pollutants, and how they will respond to climate change are largely unknown. Here, we combine data analysis of the past seven decades, high temporal resolution monitoring and model development to test this hypothesis with nine polycyclic aromatic hydrocarbons (PAHs) in the planktonic food web of a subtropical shallow eutrophic lake in China. We find biphasic correlations between both bioconcentration factors and bioaccumulation factors of the PAHs and the mean temperature, which depend on the recruitment temperatures of cyanobacteria, and copepods and cladocerans. The positive correlations between bioconcentration factors, bioaccumulation factors and the mean temperature will be observed less than approximately 13–18 days by 2050–2060 due to the shifts in plankton phenology. The PAHs and their bioaccumulation and biomagnification will respond seasonally and differently to climate change. Bioaccumulation of most of the PAHs will decrease with global warming, with higher decreasing rates appearing in winter and spring. Biomagnification of most of the PAHs from phytoplankton to zooplankton will increase with global warming, with higher increasing rates appearing in winter and spring. Our study provides novel insights into bioaccumulation and biomagnification of chemical pollutants in eutrophic waters under climate change scenarios. [ABSTRACT FROM AUTHOR]

As the largest polycyclic aromatic hydrocarbons (PAHs) emission country, China is suffering from severe PAHs pollution. Twenty-eight lakes in the middle and lower reaches of the Yangtze River region (MLYR), where numerous lakes are located in and play very important roles in the development of the local economy and society, were selected to investigate the levels and sources of the PAHs in this region and the related influence factors. Concentrations of the 16 PAHs (∑PAHs) in the sediments ranged from 221.0 to 2418.8 ng g (dry weight). The mean ∑PAHs was higher in the lower reaches than in the middle reaches. ∑PAHs in the sediments was positively correlated with the local gross domestic product (GDP), which implies that GDP was the key factor to affect the PAHs level in the sediments of study area. According to the composition of 16 PAHs, the 28 lakes were grouped into 3 clusters. Major PAHs sources for the three types of lakes were significantly different, which were biomass combustion, coal combustion, and vehicle/coal source, respectively. The total toxic benzo(a)pyrene equivalent (TEQ) of the carcinogenic PAHs in the sediments varied from 12.9 to 472.9 ng TEQ g. Benzo(a)pyrene (BaP) and dibenzo(a,h)anthracene (DaA) were the two main contributors to total TEQ. [ABSTRACT FROM AUTHOR]

• Cladocera assemblages shifted from littoral to planktonic species since 1970s. • Ecological turnover of changing sedimentary environment and increasing nutrition occurred in 1970s. • Periodical changes of eco-environment modulating by human activities and climate change occurred in Wulanpao Lake. The ecological environment of grassland lakes is closely related to water security and human health in both arid and semiarid regions. The protection of freshwater and wetland ecological environments in grasslands promotes the stable and healthy development of ecosystems in arid and semiarid areas. In the present study, we investigated the long-term eco-environmental evolution of a typical grassland lake: Wulanpao Lake, located in the Hulun Lake Basin of northern China. This region represents the junction of areas subject to monsoons and those that are not and is arid or semiarid. We used the biological indicator of subfossil Cladocera, geochemical indices, and grain size from a well-dated sediment core. The ecological environment of Wulanpao Lake was influenced by climate change, consistent with a low trophic status, and the site developed aquatic vegetation between the 1860s and 1970s. However, the observed shift from predominantly littoral to planktonic Cladocera species was accompanied by ecological turnover (changes in the sedimentary environment and increases in trophic status and organic matter) when human activities began to impact the lake environment in the 1970s. This research provides an empirical foundation for managers and policymakers to protect similar grassland freshwater eco-environments. [ABSTRACT FROM AUTHOR]

The stable isotope nitrogen-15 (N) is a robust indicator of nitrogen (N) source, and the joint use of δN and δO-NO values can provide more useful information about nitrate source discrimination and N cycle process. The δN and δO-NO values, as well as major ion tracers, from Taihu Lake in east China were investigated to identify the primary nitrate sources and assess nitrate biogeochemical process in the present study. The results show that the nitrate concentration in West Taihu Lake (WTL) was generally higher than those in East Taihu Lake (ETL) and its upstream inflow rivers. The NO/Cl value combined with mapping of δN-NO and NO concentration suggest that the mixing process should play a major effect in WTL, and denitrification was the dominant N transformation process in WTL. A linear relationship of close to ~1: 2 was observed between δN-NO and δO-NO values in WTL, confirming the occurrence of denitrification in WTL. The δN-NO data imply that sewage and manure were the principal nitrate sources in WTL and its feeder rivers, while the nitrate in ETL might derive from soil organic nitrogen and atmospheric deposition. The δO-NO data indicate most of nitrate from microbial nitrification of organic nitrogen matter possibly make a significant contribution to the lake. [ABSTRACT FROM AUTHOR]

• A system measuring performance of urban sustainability for China is formalized. • Five key factors are identified in the system using EFA and CFA. • Six cities in China and 129 experts interviews are adopted to validate the system. • A methodology for defining indicators of urban sustainability is provided. • The system emphasizes the urban service to enhance life quality for inhabitants. Urban sustainability has become a global concern. How to effectively and consistently measure urban sustainability through a metric system is a subject of debate. Based on empirical data with 377 expert samples, this study adopts exploratory factor analysis and confirmatory factor analysis to establish a metric system measuring urban sustainability that is applicable to Chinese cities. Compared to existing studies, this proposed metric system focuses on the developmental situation of China and is streamlined to 5 factors, including only 18 indicators. Environment, infrastructure, service and policies, health, and population dynamics are key factors influencing expert judgment on urban sustainability. The comprehensiveness, reusability, and formality of the metric system are further validated by interviews with 129 urban management professionals and case studies including six cities with different themes in China. The results reveal the importance of maintaining quality of life in urban sustainability, which theoretically expands the sustainability indices under the framework of the triple bottom line from a people-oriented perspective. Practically, both urban policymakers and the public can assess the sustainability of urban areas leveraged by the formalized system. It is also generalizable to evaluators who thoroughly assess similar cities in other developing countries in terms of sustainable development. [ABSTRACT FROM AUTHOR]

Highlights: [•] The residues of organochlorine pesticides in dog sharks were 10.75–30.35ng/g. [•] DDTs and chlordanes has a tendency to accumulate in the liver. [•] Direct gill penetration may be an important means of entrance for HCHs. [•] The compositional profiles suggest historical usage of HCHs and chlordanes. [•] The predominant o,p′-DDT/p,p′-DDT ratios reflected a recent use of dicofol. [ABSTRACT FROM AUTHOR]

Abstract: In 2009, two short sedimentary cores (DJZ and DQG) were collected from the East Taihu Lake at the lower Yangtze River Basin using a gravity corer. Lead isotopes and metals including Pb, Al, Fe, and Ti were measured. Radio nuclides including 210Pb and 137Cs were also analyzed for dating of the sediments at both cores. The averaged sedimentation rate at DQG site was 0.32 cm/a since the early 1960s, while at DJZ it was at least 1 cm/a. Significant decline of 206Pb/207Pb ratios were observed in DQG from the deeper sediments to near-surface sediments, indicating increased anthropogenic lead load to the lake sediments due to human impact since the 1970s. The uppermost sediments' lead contents were 2.3 times of those before the 1950s. Trends of anthropogenic lead in both cores inferred from a lead isotope mixing model were found to be similar to those from Al, Fe, and Ti normalization methods. Ti was found to be the best passive tracer element, highly in accordance with Pb isotope mixing model results. In DQG, anthropogenic lead increased sharply since the 1970s and reached a maximum in 2000s (28 mg/kg from lead isotope mixing model), while at DJZ the highest value was 20 mg/kg. These results revealed significant anthropogenic lead influx into the lake caused by human activities, in good agreement with the economic development in the past three decades in China. [Copyright &y& Elsevier]

Lakes are important in the global and regional carbon cycle, and lake sediments potentially store substantial quantities of organic carbon. The middle and lower reaches of the Yangtze River basin (MLYB) are some of the largest agricultural areas in China with an extremely high density of lakes and rivers. The lakes in the region have undergone dramatic changes over the past several decades. In this study, six cores from five lakes (the macrophyte-dominated: Shijiuhu Lake and Honghu Lake; the algae-dominated: Chaohu Lake, Taihu Lake, and Nanyihu Lake) in the MLYB were collected from 2002 A.D. to 2008 A.D. Mass accumulation rates (MARs) of sediment derived from Pb and Cs along with total organic carbon content (TOC) were used to determine organic carbon accumulation rates (OC ARs) over the last 100 years. The TOC in the five lakes exhibited a significant increase since the mid or late 20th century, which was consistent with the increase in the lake water trophic status due to nutrient input. The average organic carbon accumulation rates for the Taihu Lake, Nanyihu Lake, Chaohu Lake, Shijiuhu Lake, and Honghu Lake were calculated to be 16.6, 28.9, 9.8, 25.4, and 113.2 g C m year, respectively, over the past 100 years. Based on the average OC AR of 32.1 g C m year from the five lakes, carbon burial in lake sediments may be as much as 6.8 × 10 g C in the MLYB over the past 100 years. [ABSTRACT FROM AUTHOR]

Pollen and charcoal records of a 150 cm long lake sediment core from Taibai Lake in the middle reach of the Yangtze River reveal seven major changes in regional vegetation over the last 1500 years. During the period c. ad 480–710, evergreen broadleaved forest dominated by Castanopsis/Lithocarpus and evergreen oaks occurred in the Taibai Lake catchment. From c. ad 710 to 1050, the vegetation shifted to a mixed conifer and broadleaved forest, with Pinus expanding at the expense of Castanopsis/Lithocarpus. Between c. ad 1050 and 1320, evergreen broadleaved forest reoccupied the studied area. From c. ad 1320 to 1650, the area of primary forest decreased markedly with synchronous reduction in broadleaved trees and Pinus. Between c. ad 1650 and 1740, the biomass declined rapidly, while secondary Pinus forest began to expand. During c. ad 1740–1950, forest extent increased slightly compared with the previous stage, but the landscape was still secondary forest with the minimum proportion of broadleaved trees. After c. ad 1950, the biomass in the surrounding area was very low, with vegetation types similar to that at present (secondary Pinus forest and mixed conifer and broadleaved forest). A detrended correspondence analysis (DCA) with 125 samples and 34 main pollen types is used to separate human and climatic impacts on vegetation. Then, the pollen assemblage, DCA, charcoal record, and magnetic susceptibility are combined to discuss the key factors inducing these vegetation changes. The vegetation changes were mainly controlled by the climatic changes, with the weak impacts of human activities before c. ad 1320. Since then, the intensity of human influences on vegetation increased gradually, entering a transitional period of main controlling factors of vegetation changes from nature to human activities. After c. ad 1740, the vegetation changes were chiefly controlled by human activities, and the climatic signal was weak. [ABSTRACT FROM AUTHOR]

In June 2009, two short sedimentary cores, wdlc-3 and wdlc-5, were collected from Wudalianchi Lake (48°40′ N ∼ 48°47′ N, 126°06′ E ∼ 126°15′ E) in the north central of Heilongjiang Province, northeastern China, using a gravity corer. The catchment erosion and trophic status changes were studied by an interpretation of the variations of multi-proxies, including organic matter (loss on ignition (LOI 550°C ) and total organic carbon (TOC)), total phosphorus (TP), total nitrogen (TN), magnetic susceptibilities, organic carbon isotope (δ 13 C org ) and grain size. Sediment accumulation rates (SARs) and ages were determined using a composited model of the 210 Pb or 137 Cs methods, respectively. The results are as follows: 1) the average sediment rate was 0.28 g cm −2 y −1 (0.59 cm y −1 ) in wdlc-3 and 0.25 g cm −2 y −1 (0.55 cm y −1 ) in wdlc-5 over the past 100 years. The interaction of the large-scale land reclamation and rainfall were related to high sediment accumulation rates before the 1980s; after the 1980s, however, the changes of precipitation were most likely the main influencing factor on SARs. 2) The δ 13 C org values ranged from −26.78 to −25.79‰ in wdlc-3 and −25.82 to −21.95‰ in wdlc-5. The TOC and TN showed an upcore increasing tendency, and TN, TOC and TP showed a dramatic increase since the 1980s. Based on the multi-proxies, the sediments recorded the change of the aquatic plant community from macrophyte-dominant to algae-dominant in the third lake and to macrophyte and algae coexistence in the fifth lake, also reflecting the changes of trophic status over the past 100 years. 3) Large-scale reclamation was the main factor impact the lake environment before the 1980s; after the 1980s, enhanced agricultural activities such as extensive use of fertilizers and the discharge of domestic waste water resulted in dramatic changes in the lake environment. [ABSTRACT FROM AUTHOR]

A large portion of polychlorinated biphenyls (PCBs) from e-waste released into the coastal areas may be the potential source of PCBs to the global oceans. The paper presents data of PCBs concentrations in fifty surface sediment samples and a dated sediment core in Yangtze River Delta (YRE) and adjacent East China Sea (ECS). The total PCBs levels varied from 5.08 to 19.64 ng/g dry weight, with the highest concentrations situate within the river-sea boundary zone which is so-called “marginal filter”. Concurrent with the operation of e-waste recycling over the last two decades, PCB fluxes started to rise again after 1980s and reached a maximum in this century. The full data set was used to estimate the burden of PCBs in YRE and adjacent ECS. A total sediment burdens were 192.8 tons, with the spatial density of 364 ng/cm2 which accounts for 1.9% of all the PCBs in China. [Copyright &y& Elsevier]

In the present study, δ15N and δ18O-NO3- values, as well as concentrations of some major ion tracers were determined in seasonal water samples from Taihu Lake and major watersheds to investigate the temporal and spatial variations of nitrate sources and assess the underlying nitrogen (N) biogeochemistry process. The results lead to the conclusion that the nitrate concentrations in Taihu Lake are lower in summer than that in winter due to the dilution effect of wet deposition. In winter, sewage and manure were the primary nitrate sources in major inflow rivers and North Taihu Lake (NTL), while nitrate sources in East Taihu Lake (ETL) probably derived from soil organic N. In summer, atmospheric deposition and sewage/manure inputs appear to play an important role in controlling the distribution of nitrates in the whole lake. The δ18O-NO3- values suggest that the nitrate produced from microbial nitrification is another major nitrate source during both winter and summer months. The variations in isotopic values in nitrate suggest denitrification enriched the heavier isotopes of nitrate in NTL in winter and in ETL in summer. [ABSTRACT FROM AUTHOR]

We present a sedimentary geochemical record of human perturbation in the watershed and related changes in trace metals (Cr, Ni, Zn and Pb), phosphorus and abundant rock-forming elements (Al, Fe, K, Mg, etc.) in Chaohu Lake over the past 500 years, a period spanning historical agricultural expansion and modern economic development. The record exhibited a stable terrestrial detrital input to Chaohu Lake before ca. 1540 AD, a period with less human perturbation of the watershed, which resulted in low and constant values of trace metals and phosphorus (TP) concentrations as well as Al, Fe, K, Mg, fine silt (<16 μm), the chemical index of alteration (CIA) and K/Na ratio. Two periods of successive marked increases in Al, Fe, K, Mg, fine silt, chemical index of alteration (CIA) and K/Na ratio occurred after ca. 1540 AD and 1950 AD. The former period apparently resulted from enhanced well-weathered topsoil erosion in the watershed related to the expansion of arable land, and the latter resulted from further enhancement of human perturbation in the watershed during the modern period. Concentrations of trace metals and TP were positively correlated with that of the rock-forming elements and fine silt. Trace metal pollution was limited during 1540-1950 AD, according to the low enrichment factors (EFs = 0.8-1.1), when an increase in trace metal concentrations was also linked to changes in detrital input. In addition to detrital regulation, pollution also contributed to an increase in TP concentrations (average EF 1.4) during 1540-1950 AD and the average accumulation rate of anthropogenic phosphorus was 87.3 mg ma. Anthropogenic phosphorus increased further and Pb and Zn pollution also occurred after 1950 AD, reaching maximum values after 1980 AD, when the average accumulation rates of anthropogenic Zn, Pb and phosphorus (mainly in the form of NaOH-P) were 242.2, 43.3 and 811.8 mg ma, respectively. The increase in phosphorus pollution in recent decades is probably from the domestic sewage sources of Hefei City and non-point sources related to agricultural utilization of commercial fertilizer, whereas Zn and Pb pollution is probably derived mainly from industrial sources of Hefei City, as deduced from their spatial variations in the sediments of the river mouths. [ABSTRACT FROM AUTHOR]

Objective: To assess health-related quality-of-life (HRQoL) 2 years after traumatic brain injury (TBI) among a group of Chinese. Methods: A total of 358 adult patients with moderate-to-severe TBI based on Glasgow Coma Scale score were recruited in a large trauma centre in Wuhan, China during May 2005 to April 2008. They were followed up for 2 years and the Medical Outcome Short Form 36 was used to measure HRQoL. Results: After a 2-year follow-up, there were 312 (87.2%%) survivors. All domains of HRQoL had the lowest scores at discharge, greatly improved over the first 6 months and showed continued improvement. Patients with TBI still had significantly lower scores in every domain than the reference group 2 years after discharge. Female patients had lower MCS scores than the males (OR == 1.8, 95%% CI: 1.1-2.9). Patients older than 30 had lower scores in PCS (OR == 1.7, 95%% CI: 1.1-2.6). Patients with severe TBI had lower scores in both PCS (OR == 1.9, 95%% CI: 1.2-3.1) and MCS (OR == 1.6, 95%% CI: 1.0-2.6) compared with those with moderate TBI. Conclusions: HRQoL of a group of Chinese patients with TBI improved during 2 years after discharge. Age, sex and severity of TBI were significantly associated with physical or mental HRQoL after discharge. [ABSTRACT FROM AUTHOR]

Abstract: This study attempted to quantify the lake sedimentation and its role in recording catchment soil erosion in the lower reaches of the Yangtze River basin, using cesium-137 (137Cs, anthropogenic) and lead-210 (210Pb, natural) dating. Six cores taken from five lakes, including the two largest lakes in the region (Taihu, Chaohu), were selected for understanding the change of sedimentation rates. High rates of sediment accumulation between the late 1920s and the late 1960s in the three lakes of the Qinyi-Shuiyang River basin showed good correlation with farmland change in adjacent counties, indicating enhanced human-induced soil erosion in the catchment. Chaohu Lake core to some extent also recorded catchment erosion, e.g., high flux in the late 1960s consistent with catchment disturbance. However, at Taihu Lake, sediment accumulation rates do not generally reflect catchment erosion history. Sediment accumulation rates of large shallow lakes in the lower Yangtze River basin do not accurately record soil erosion, whereas relatively small lakes may be sensitive to catchment disturbance. [Copyright &y& Elsevier]

Abstract: The spatial distribution and source of polychlorinated biphenyls (PCBs) in 30 surface sediments of Yueqing Bay, Xiangshan Bay, and Sanmen Bay in Eastern China were analysed. Total concentrations of PCBs ranged from 9.33 to 19.60ngg−1 dry weight for all the sampling stations. The observed PCB levels were lower than those in areas of high urbanisation or contamination in the bay. Low-chlorinated PCBs, dominated by tri-PCB, were identified as the prevalent contaminate of surface sediments, and the top three PCB congeners were lighter chlorinated congeners (PCB 8, PCB 18 and PCB 28). These results were in agreement with the fact that tri-PCB compounds are the dominant contaminants in China. The result of the principal component analysis revealed that all samples were similar in composition to Aroclor 1242, suggesting they might originate from electrical capacitors and transformers. The levels of PCBs were significantly correlated with the total organic carbon in the sediments. [Copyright &y& Elsevier]

Residual levels and enantiomeric signatures of hexachlorocyclohexanes (HCHs) and dichlorodiphenyltrichloroethanes (DDTs) in surface sediments from Xiangshan Bay, East China Sea were investigated. The concentrations of ∑HCHs (sums of α-, β-, γ-, and δ-HCH) and ∑DDTs (sums of p, p'-DDT, p, p'-DDD,p, p'-DDE, o, p'-DDT, and o, p'-DDD) ranged from 0.14 to 0.67 ng g-1 and 0.61 to 22.38 ng g-1, respectively. A slight potential health risk to the organism was then indicated for the residual levels of DDTs according to the ERL/ERM guidelines. Moreover, the predominant β-HCH implied that the technical HCH contamination was mainly due to the historical usage. But the high ratio of DDT/∑DDTs depicted a cocktail input pattern of fresh and weathered DDTs. The enantiomeric fractions (EFs) of α-HCH, o, p'-DDT, and o, p'-DDD were also determined. The degradation of α-HCH was enantioselective in all sediments samples, resulting in an enrichment of (-)-enantiomers. However, the racemic residues of o, p'-DDT and o, p'-DDD were observed in all sediments samples. [ABSTRACT FROM AUTHOR]

Abstract: The lakes along the middle-lower Yangtze River Basin have undergone dramatic water quality deterioration and eutrophication during recent decades. The nutrient and metal accumulation in the lake sediments through time were investigated using the sedimentary-geochemical records of the drilling cores from several typical lakes. The results showed a general increase in total organic carbon and total nitrogen concentration with lower depth in the profiles. Increased delivery of organic matter to the lake system could be responsible for the nutrient enrichments in the lake bottom sediments. The general trend of nutrients matter enriched upwards in the core indicated that these lakes had become eutrophic since the mid-1950s (macrophyte-type lake), or late 1980s (algae-type lake). In addition, the results have also shown that human activities have exerted a great influence on the past lake environmental changes since the 1950s, inferred from the changes in the sedimentary rate and the anthropogenic metal accumulation in the sediment cores. Enhanced human activities seem to occur around the early 1970s. [ABSTRACT FROM AUTHOR]