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Background: Microbiota may be associated with esophageal squamous cell carcinoma (ESCC) development. However, it is not known the predictive value of microbial biomarkers combining epidemiological factors for the early detection of ESCC and precancerous lesions. Methods: A total of 449 specimens (esophageal swabs and saliva) were collected from 349 participants with different esophageal statuses in China to explore and validate ESCC-associated microbial biomarkers from genes level to species level by 16S rRNA sequencing, metagenomic sequencing and real-time quantitative polymerase chain reaction. Results: A bacterial biomarker panel including Actinomyces graevenitzii (A.g_1, A.g_2, A.g_3, A.g_4), Fusobacteria nucleatum (F.n_1, F.n_2, F.n_3), Haemophilus haemolyticus (H.h_1), Porphyromonas gingivalis (P.g_1, P.g_2, P.g_3) and Streptococcus australis (S.a_1) was explored by metagenomic sequencing to early detect the participants in Need group (low-grade intraepithelial neoplasia, high-grade intraepithelial neoplasia and ESCC) vs participants without these lesions as the Noneed group. Significant quantitative differences existed for each microbial target in which the detection efficiency rate was higher in saliva than esophageal swab. In saliva, the area under the curve (AUC) based on the microbial biomarkers (A.g_4 ∩ P.g_3 ∩ H.h_1 ∩ S.a_1 ∩ F.n_2) was 0.722 (95% CI 0.621–0.823) in the exploration cohort. Combining epidemiological factors (age, smoking, drinking, intake of high-temperature food and toothache), the AUC improved to 0.869 (95% CI 0.802–0.937) in the exploration cohort, which was validated with AUC of 0.757 (95% CI 0.663–0.852) in the validation cohort. Conclusions: It is feasible to combine microbial biomarkers in saliva and epidemiological factors to early detect ESCC and precancerous lesions in China. [ABSTRACT FROM AUTHOR]

Purpose: Unlike ordinary products, festival food gifts like mooncakes in China are prone to excessive packaging, using various materials and complicated decorations, which increases the resource and environmental burdens of consumption. This study evaluated the environmental impacts of different mooncake packaging options, including metal, wood, and paper-based packaging. Methods: This study sampled 64 mooncake packaging types (with low, medium, and high prices) in the Chinese market and employed life cycle assessment modeling to quantify and analyze the environmental impacts of different mooncake packaging types. Based on these results, this study identified environmental-friendly options and shed light on directions to alleviate unnecessary environmental impacts associated with the packaging of massive seasonal festival food. Results and discussion: The weight of packing materials associated with 1 kg of mooncake product ranged from 0.5 to 2.5 kg (with a mean value of 1.2 kg), resulting in average greenhouse gas emissions of 2 kg of CO2-eq, or approximately 67 times the value of ordinary food packing (0.03 kg of CO2-eq). Among the three packaging types, metal-based packaging had the highest environmental impacts, followed by wood and paper-based packaging. The outer packaging was the dominant contributor to the environmental impacts of metal-based packaging, while the impacts of wood and paper-based packaging were primarily derived from the middle packaging materials, which mainly consisted of individual packaging boxes and fixed pallets. Higher-priced mooncakes had heavier packaging weight and greater environmental impacts, suggesting that they bear more environmental responsibility. Conclusion: Excessive and extravagant packaging was responsible for the increasing environmental burden associated with mooncakes. For both mooncake producers and consumers, turning back to the essence of the festival itself will be crucial for mitigating the environmental impacts of packaging. This study is an initial attempt to quantify the environmental impacts of traditional festival food packaging, and the study results facilitate evidence-based policymaking to transition the festival commodity packaging sector in a more sustainable direction. [ABSTRACT FROM AUTHOR]

Background: Esophageal cancer (EC) is one of the leading contributors to the global burden of cancer, and the underlying mechanism is still unknown. Recently, there has been a growing interest in understanding modifiable psychosocial risk factors, particularly depression, to prevent EC and reduce morbidity and mortality. However, related research is sparse and has been ignored. The study was designed to assess the association between depression and EC in China. Methods: From 2017 to 2019, a population-based multicenter study was conducted in high-risk regions of EC. Participants underwent a free endoscopy screening. If the endoscopic results were suspicious, a pathological biopsy was applied to confirm. Depression was measured with Patient Health Questionnaire-9 (PHQ-9). In addition, information on demographic characteristics and risk factors was collected from participants by trained interviewers using uniform questionnaires. Results: After Endoscopy and pathologic diagnosis, 15,936 participants in high-risk regions of EC (ECHRRs) were enrolled, 10,907 (68.44%) of which were diagnosed health, 4048 (25.40%) with esophagitis, 769 (4.83%) with low-grade intraepithelial neoplasia (LGIN), 157 (0.99%) with high-grade intraepithelial neoplasia (HGIN), and 55 (0.35%) with EC, respectively. The overall prevalence of depression symptoms of participants was 4.16% (health: 4.63%, esophagitis: 2.99%, LGIN: 2.99%, HGIN: 5.73%, and EC: 9.09%). Multiple logistic regression analyses revealed that the unadjusted OR (95% CI) between depression and each esophageal pathology grades were esophagitis 0.93 (0.92-0.95), LGIN 0.97 (0.94-0.99), HGIN 1.05 (1.00-1.10), and EC 1.04 (0.97-1.14), respectively. However, after adjustment for potential confounders (age, gender, region, alcohol consumption, BMI), no statistically significant associations between depression and EC (adjusted OR = 1.10, 0.99-1.21) and esophageal lesions (esophagitis: adjusted OR = 1.02, 0.99-1.04; LGIN: adjusted OR = 0.98, 0.95-1.01; HGIN: adjusted OR = 1.04, 0.98-1.11) were observed in this study. Conclusions: No significant association was observed between depression and EC in the study. Future prospective cohort studies are needed to verify this preliminary finding. [ABSTRACT FROM AUTHOR]

In our study, we aimed to assess the long‐term risk of gastric cardia adenocarcinoma (GCA) for patients with different histological cardia lesions to inform future guidelines for GCA screening in China. We conducted a population‐based prospective study among 9740 subjects who underwent upper endoscopy screening during 2005 to 2009 and followed until December 2017. Cumulative incidence and mortality rates of GCA were calculated by the baseline histological diagnoses, and the hazard ratios (HRs), overall and by age and sex, were analyzed by Cox proportional hazards models. During a median follow‐up of 10 years, we identified 123 new GCA cases (1.26%) and 31 GCA deaths (0.32%). The age‐standardized incidence and mortality rates of GCA were 128.71/100 000 and 35.69/100 000 person‐years, and cumulative incidence rate in patients with cardia high‐grade dysplasia (CHGD), cardia low‐grade dysplasia (CLGD) and atrophic carditis (AC)/cardia intestinal metaplasia (CIM) was 25%, 3.05% and 1.58%, respectively. The progression rate and cancer risk of GCA increased monotonically with each step in Correa's cascade. Individuals aged 50 to 69 years had 4.4 times higher GCA incidence than those aged 40 to 49 years. Patients with CLGD had a significantly higher 3‐year GCA incidence than the normal group, while patients with AC/CIM had a comparable GCA risk during 3‐year follow‐up but a higher risk at 5‐year intervals. Our results suggested a postponed starting age of 50 years for GCA screening, immediate treatment for patients with CHGD, a 3‐year surveillance interval for patients with CLGD, and a lengthened surveillance interval of 5 years for patients with AC/CIM. [ABSTRACT FROM AUTHOR]

Almost 50% of the world's esophageal cancer (EC) cases occur in China, and the impact of cancer screening has long been a controversial topic. The study was designed to evaluate the biological correlates of EC screening and subsequent diagnosis in China. Based on the national cohort of esophageal cancer program, a prospective multicenter study in high-risk regions was conducted from 2017 to 2019. 61 participants received twice esophageal endoscopy screening and pathological biopsy successively (with a mean follow-up of 14.03 months). Box–Cox-power transformation and two-way repeated measures ANOVA were used to evaluate hormone cortisol and immunoglobulin (IgA, IgG, IgM) levels in plasma, reflecting their stress, immune function, and biological correlates before screening and after knowing the diagnosis. The median of cortisol, IgA, IgG, and IgM in pre-screening was 15.46 ug/dL, 1.86 g/L, 12.14 g/L, and 0.91 g/L, corresponding value at post-diagnosis was 15.30 ug/dL, 2.00 g/L, 12.79 g/L, and 0.94 g/L, respectively. No significant differences in biological indicators were found between normal and esophagitis and low-grade intraepithelial neoplasia before screening and after diagnosis. After normality transformation, cortisol, IgA, IgG and IgM levels were (0.25 ± 0.04) U/mL, (0.72 ± 0.13) (g/L), (2.44 ± 0.22) (g/L) and (0.98 ± 0.25) (g/L) before screening, (0.25 ± 0.05) U/mL, (0.70 ± 0.13) (g/L), (2.48 ± 0.21) (g/L) and (1.00 ± 0.25) (g/L) after diagnosis, respectively. Repeated Measures ANOVA showed that the main effects were significant on IgA levels between pre-screening and post-diagnosis (P = 0.019). No interaction effects on biological levels between pre-post screening and esophageal pathology, anxiety states (all P > 0.05). Little biological correlates were found both before screening and after diagnosis. Cortisol and IgA dropped less significantly, while IgM and IgA were increased slightly after diagnosis. Further multi-round longitudinal studies are needed to validate these results. [ABSTRACT FROM AUTHOR]

Background and Aim: This study aimed to evaluate effects of endoscopic screening method in different starting age groups and further confirm the optimum starting age for esophageal squamous cell cancer (ESCC) screening. Methods: This study received institutional review board approval, and 6825 residents aged 40 to 69 years in high prevalence communities were assigned to the screening group or the control (non‐screening) group from Hebei, China. Cumulative mortalities during the 14‐year period, relative risk for participants who underwent screening, and numbers needed to invite for screening to save one life were compared between the screening group and the control group of different starting age groups at 14‐year follow‐up. Results: The 14‐year risks of ESCC mortality were one in 55, one in 17, and one in 9 for a person screened in the starting age group of 40, 50, and 60 years old. The cumulative mortalities of ESCC in screening groups were significantly lower than control groups in starting age groups of 40 years (1.42% vs 2.38%, P = 0.033) and 50 years (4.18% vs 7.13%, P = 0.005). Relative risks for participants who underwent screening were 0.60 and 0.59 for the starting age groups of 40 and 50 years. Numbers needed to invite for screening to save one life were 104 and 34 for participants in 40 years old group and 50 years old group, respectively. Conclusions: In conclusion, people in high prevalence area of ESCC should have endoscopy screening once at their 50 years. Forty years will be preferably defined as the starting age for screening in areas with sufficient health resources. [ABSTRACT FROM AUTHOR]

Background: Helicobacter pylori (H. pylori) is widely accepted to be the most important cause of gastric non-cardia adenocarcinoma (GNCA), while its role in the development of gastric cardia adenocarcinoma (GCA) is not well-defined. We aimed to investigate current H. pylori infection in relation to the severity of both precancerous and cancerous lesions of the gastric cardia in an Asian population at high risk of GCA. Methods: A population-based cross-sectional study was conducted in Linzhou County, Henan Province, China. Two thousand three (2,003) randomly selected participants with data on current H. pylori infection, assayed by 13C-urea breath test (13C-UBT), and a sequence of histological diagnoses of the gastric cardia mucosa were analyzed. Results: Of 2,003 subjects, 828 (41.33%) were currently infected with H. pylori. The prevalence of current H. pylori infection increased with increasing severity of histological lesions, from 34.12% in subjects with normal gastric cardia mucosa to 52.17% in subjects with gastric cardia high-grade intraepithelial neoplasia (CHIN)/ gastric cardia adenocarcinoma (GCA) (P for trend <0.001). With H. pylori -negative subjects as the reference category, H. pylori -positive subjects had statistically significant elevated adjusted prevalence odds ratios (PORs) for each of the histological lesions. The PORs (95% CI) were 2.15 (1.74–2.64), 3.46 (2.08–5.75), 2.78 (1.90–4.07), and 3.05 (1.30–7.17) for subjects with carditis, cardia intestinal metaplasia (CIM), cardia low-grade intraepithelial neoplasia (CLIN), and CHIN/GCA), respectively. The associations remained when subjects with abnormal stomach non-cardia mucosa were excluded. Conclusions: This large epidemiologic study demonstrates a positive association between current H. pylori infection and the severity of both precancerous and cancerous lesions of the gastric cardia in an Asian population at high risk of GCA. These findings suggest that H. pylori infection may play a role throughout both early- and late-stage development of GCA. [ABSTRACT FROM AUTHOR]

A 5.3 m lake core was drilled in Baahar Nuur Lake in the Ordos Plateau, and measurements of mean grain size, organic δ13C (δ13Corg), organic carbon content (TOC), C/N, carbonate content, carbonate δ13C (δ13Ccar) and δ18O (δ18Ocar) were conducted for retrieving the Holocene chronosequence of climatic changes based on 15 AMS 14C dates. The record documented four major stages of climate change in the Ordos Plateau: (IV) a cold and dry condition before ~7.65 14C ka BP; (III) a warm and humid stage between ~7.65 and ~5.40 ka BP; (II) a generally drier and cooler climate since ~5.40 ka BP with two humid events occurring from ~4.70 to ~4.60 ka BP and from ~4.20 to ~3.70 ka BP, and (I) a dry climate characterized by complete desiccation of the lake after 3.70 ka BP. Stage Ill can be further divided Into three sub-stages: (IIIa) a warm and humid episode from ~7.65 to ~6.70 ka BP, (IIIb) a warm and relatively dry episode from ~6.70 to ~6.20 ka BP, and (IIIc) the magthermal and maghumid episode of the Holocene from ~6.20 to ~5.40 ka BP. [ABSTRACT FROM AUTHOR]

Studies recorded formate and acetate in a mid-latitude glacier in west China. Relationship of the occurrence of formate and acetate with processes in the biosphere; Average concentration of acetate and formate in the area; Formate to acetate ratio average.

The previous studies an association between dietary patterns and psychiatric symptoms. However, few studies have examined the association of quality of dietary patterns and anxiety, depressive symptoms in the Chinese population. Between 2017 and 2019, a population-based, cross-sectional survey was carried out in China. Uniformed questionnaires collected the demographic characteristics and food data. The dietary quality of the adults was evaluated using the revised Diet Balance Index 2016 (DBI-16). We measured anxiety and depression symptoms using the the Generalized Anxiety Disorder (GAD)-7 and Patient Health Questionnaire (PHQ)-9. A total of 73,737 participants were recruited during the survey period. 17.6 % and 13.7 % of residents suffer from anxiety and depression symptoms, respectively. The DBI-16 indicates that participants with anxiety or depression symptoms had higher scores of low bound score (LBS, refers to inadequate food intake) and dietary quality distance (DQD, refers to unbalanced food intake) than those without anxiety or depression. The logistic regression models showed that high levels of LBS and DQD problems were more strongly associated with anxiety (LBS:OR = 1.20, DQD:OR = 1.30) and depressive symptoms (LBS:OR = 1.21, DQD:OR = 1.44). On the contrary, higher bound score (HBS, refers to excessive food intake) was significantly negatively correlated with symptoms of anxiety and depression. Moreover, each increase in the food group was associated with 4 % lower odds of anxiety and 6 % lower odds of depression symptoms. Cross-sectional design and self-reporting of psychological symptoms and dietary information limit the generalizability of the results. The dietary quality of adults aged 40 years and over in China is suboptimal, with excessive and inadequate food intake simultaneously. Dietary imbalance, and low dietary diversity may be related to anxiety and depressive symptoms. • This is the first study to examine the associations between dietary quality and general psychological symptoms of the Chinese adults aged 40 and older; • The DBI-16 reflects dietary quality through inadequate, excessive intake and dietary balance status; • The overall dietary quality of adults aged 40 years and over in China is suboptimal; • Dietary imbalance, and low dietary diversity may be related to anxiety and depressive symptoms; [ABSTRACT FROM AUTHOR]

Urbanization and globalization are changing the conventional constraints of seasonality and geography on food consumption, such as that of fresh cherries. The rising demand for year-round cherry consumption in China is currently satisfied by open-field, greenhouse-produced, and imported products. This study conducted a spatial-temporal life cycle evaluation of the environmental performance of cherry consumption behaviors during different seasons of the year. Moreover, based on the definitions of global and local seasonality, the additional environmental costs of out-of-season cherry consumption were estimated. Results show that seasonality was an important factor affecting the environmental burdens of cherry consumption. Eating cherries imported from Chile by air in October resulted in the highest greenhouse gas (GHG) emissions of 6.38 kg CO 2 -eq/kg, while eating domestic open-field cherries during May to July (the natural harvest season) was a relatively environmentally beneficial option. The total cherry consumption in China in 2019 generated GHG emissions of 126.99 × 104 t CO 2 -eq. Under the definitions of global and local seasonality, the out-of-season consumption led to additional environmental costs of 57.59 × 104 and 85.67 × 104 t CO 2 -eq, accounting for 45.35% and 67.46% of total emissions, respectively. Furthermore, the time-environment trade-off effect of cherry consumption illustrates the higher environmental costs are exchanged for satisfying the appetite for out-of-season fresh foods. Our findings emphasize the meaningful implications for developing a sustainable consumption pattern for all stakeholders involved in the entire food chain. • Spatiotemporal life cycle assessment was performed on cherry environmental impacts. • The environmental effects of consumption behavior at different times varied. • Seasonality was an important factor affecting cherry consumption-linked impacts. • Catering to year-round appetite for fresh food incurred time-environment trade-off. • Developing sustainable consumption requires joint effort from all stakeholders. [ABSTRACT FROM AUTHOR]

Introduction: Oesophageal cancer (OC) is one of the most common cancers worldwide and about 50% of all new cases occurred in China. Population-based screening has been conducted in high-risk areas in China since 1970s, however, a few factors have limited the integration of the results from previous studies and the sharing of existing resources, such as the difference in screening methods and protocols, inconsistencies in questionnaires for risk factors investigation, lack of standards for sample collection and incomplete follow-up information., Methods and Analysis: The National Cohort of Esophageal Cancer-Prospective Cohort Study of Esophageal Cancer and Precancerous Lesions based on High-Risk Population (NCEC-HRP) is a prospective cohort study of OC screening based on high-risk population in China supported by the National Key R&D Programme. Eight areas located at eastern, central and western China are selected as screening centres to represent three economical-geographical regions. All local residents aged 40-69 years in the selected areas are invited to take endoscopic examination and risk factors investigation unless they meet the exclusion criteria. The recruitment began on June 2017 and a total of 100 000 participants will be enrolled by December 2020 and all subjects will be followed for a long time. This study is designed as open-ended and has broad research aims. Summary statistics for baseline information will be reported after the completion of recruitment. We will develop a series of standards and guidelines for OC screening during the study. An open and shared research platform linked with epidemiological databases and biobank will be built up for further research., Ethics and Dissemination: The study is approved by the Ethics Committee of Cancer Institute and Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College (approval number 16-171/1250). The findings of the study will be disseminated through scientific peer-reviewed journals as well as the public via the study website (http://www.ncec-china.cn)., Trial Registration Number: ChiCTR-EOC-17010553; Pre-results., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2019. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

Objective: To understand the distribution of esophageal squamous cell cancer and precursor lesions in high-risk areas of China, and to provide evidence for determining the reference ranges of detection rates in high-risk areas., Methods: Endoscopy with Lugol's iodine staining was performed on 15 709 local residents aged 40 to 69 years old in Linzhou of Henan province and Feicheng of Shandong province from 2005-2009. 35 cases without accurate pathology diagnosis and 11 cases with vital disease before screening were excluded. 15 663 subjects were enrolled in this study. Compliance was calculated by the percentage of the people who had endoscopic screening among the target population. Chi-square test and trend chi-square test were used to compare the distribution differences in age, gender and areas of esophageal squamous cell cancer and precancer. 95% CI of the detection rates was then employed to represent the reference ranges of esophageal squamous cell cancer and precursor lesions., Results: The compliance rate of screening endoscopy of this study was 49.36% (15 709/31 826) of all, and female's compliance (54.05%, 8 447/15 628) was much higher than that of male (44.83%, 7 262/16 198) (χ(2) = 88.14, P < 0.001). The detection rates of basal cell hyperplasia, low grade intraepithelial neoplasia, high grade intraepithelial neoplasia and esophageal squamous cell cancer of males were 4.17% (302/7 246), 17.22% (1 248/7 246), 1.67% (121/7 246), 0.83% (60/7 246), and were higher than that of females (3.45% (290/8 417), 14.82% (1 247/8 417), 1.41% (119/8 417), 0.48% (40/8 417), respectively). Except for high-grade intraepithelial neoplasia, the detection rates of male were higher than that of female (P values were 0.018, < 0.001, 0.960, 0.006). The detection rates of all grades of precursor lesions increased with age rising (all P values < 0.001), among which the detection rates of the mentioned four lesions for 40-44 years old were 2.69% (94/3 500), 8.11% (284/3 500), 0.40% (14/3 500), 0.14% (5/3 500), and that of 65-69 years old were 5.46% (46/843), 23.25% (196/843), 3.68% (31/843), 2.14% (18/843). The proportion of esophageal precursor lesion of Linzhou were higher than that of Feicheng observably except for esophageal squamous cell cancer (P values were < 0.001, < 0.001, < 0.001, 0.437). The detection rates of the four lesions of Linzhou and Feicheng were 4.90% (504/10 287), 17.37% (1 787/10 287), 1.79% (184/1 0287), 0.60% (62/10 287) and 1.64% (88/5 376), 13.17% (708/5 376), 1.04% (56/5 376), 0.71% (38/5 376). The 95% CI of detection rates of various lesions were, 3.78% (3.48%-4.08%) for basal cell hyperplasia, 15.93% (15.37%-16.50%) for low-grade intraepithelial neoplasia, 12.31% (11.79%-12.82%) for mild dysplasia and 3.62% (3.33%-3.91%) for moderate hyperplasia, 1.53% (1.34%-1.72%) for high-grade intraepithelial neoplasia and 0.64% (0.51%-0.76%) for esophageal squamous cell cancer, respectively., Conclusion: Up to 21.88% residents that were asymptomatic were suffered from esophageal squamous cancer or precursor lesions in high-risk areas in China. The distribution of esophageal squamous cell cancer and precursor lesions was closely related to the gender and the age, which suggested that males were supposed to be paid more attention to.

The identities and concentrations of low-molecular-weight organic acids (LMWOAs) were determined by ion chromatography throughout a 20-m water column in Hongfeng Lake, China. The spatiotemporal variations of LMWOAs and their contributions to dissolved organic matter (DOM) in a research period of 24 hr were also investigated. The results demonstrated that five LMWOAs (lactic, acetic, pyruvic, sorbic, oxalic acid) were detected, and their total concentration and proportion in DOC were 6.55 micromol/L and 7.47%. Their average levels were 2.50, 0.65, 2.35, 0.96 and 0.09 micromol/L, respectively. LMWOAs were higher during daytime (10:00-18:00 on Jun 13, 2008) than nighttime (21:00-6:00 the next morning), in particular 4.99 micromol/L high in the epilimnion (< or = 1 m water depth), reflecting the fact that direct import from terrigenous sources and photochemical production from humic materials were dominant during LMWOAs' origin and accumulation. The same factors caused LMWOAs to be 0.63 micromol/L in the epilimnion higher than in the hypolimnion. The rapid decrease of total organic acid (TOA) up until 18:00 mainly resulted from bio-uptake and mineralization in the hypolimnion (>1 m water depth). Pyruvic acid increased with time in the epilimnion and decreased in the hypolimnion, largely related to the two contrary processes of continuous degradation and synthesis of macromolecular organic matter during life materials' cycle mediated by organisms. Simultaneously, plankton behavior and thermal stratification played a pivotal role in LMWOAs' behavior in the water column, causing decreasing and increasing profiles. The distribution of LMWOAs represents an interesting resource for biogeochemical research of DOM in aquatic ecosystems.

Low-molecular-weight organic acids (LMWOAs) in eutrophic lake water of Dianchi, Southwestern China Plateau were investigated diurnally and vertically using ion chromatography. Two profiles (P1 and P2) were studied due to the difference of hydrochemical features. Lactic, formic, pyruvic and oxalic acid were detected as major components at P1 and P2 which were on average 7.98 and 6.53 micromol/L, respectively, corresponding to their proportions of 2.68% and 2.48% relative to DOC. Pyruvic acid was regarded as the uppermost species at P1 and P2, reaching up to 3.82 and 3.35 micromol/L and accounting for 47.9% and 51.3%, respectively, in individual TOA. Although humus were of biogenetic production at both sites, the significant negative correlation between diurnal variations of TOAs, fluorescence intensity (FI) of protein-like components and humic-like components at P1 indicated LMWOAs were greatly originated from bacterioplankton excretion and degradation. However, correlations between diurnal variations of humic-like FI and physicochemical parameters demonstrated algal origination of LMWOAs at P2. Although content of humus was high, TOA at P2 was 1.45 micromol/L lower than that at P1, due to the co-influence of more intense photo-oxidation and aggregation at P2. Therefore, TOAs exhibited quite opposite diurnal variation trends of increasing-decreasing and decreasing-increasing at P1 and P2, respectively. Except for impact of solar radiation, bacterial decomposition and assimilation rendered shifts of maximal LMWOAs along water column at P1. Covering with massive algae, UV rays penetrated shallower depth that LMWOAs assembled in surface layer water before 18:00 at P2 and represented decreasing profiles.