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In this study, sediment grain size (MGS), specific surface area (SSA), total organic carbon (TOC) contents, C/N molar ratios, stable carbon isotope, and P species in a sediment core, collected from the East China Sea (ECS) inner-shelf were measured to explore the applicability of detrital phosphorus (De-P) as a potential indicator of past flooding events in the Changjiang River Basin (CRB). In particular, we examined the linkages between the evolution of floods with regional climate changes and anthropogenic activities in the CRB. Peaks of De-P concentrations in sediments corresponded well with the worst flooding events of the CRB over the past two centuries (e.g., 1850s, 1860s, 1900s, 1920s, 1950s, 1980s, and 2000s). Moreover, De-P also corresponded well with the extreme hypoxic events in 1981 and 1998 in the Changjiang Estuary as indicated by Mo/Al ratios, indicating potential linkages between De-P as a flooding proxy to flood-induced hypoxia events in this region. In addition, a robust relationship was found among De-P, the floods in 1950s, 1980s, and 2000s of the CRB, the intensive El Niño-Southern Oscillation (ENSO), the abnormally weak East Asian Summer Monsoon (EASM) and the warm phase of Pacific Decadal Oscillation (PDO), suggesting that De-P also provided insights to linkages between regional climate change and flooding events in this region. [ABSTRACT FROM AUTHOR]

• Parent material and cropping system had higher explanation to stratification. • Clay loam soils had a weaker stratification compared to sandy loam soils. • Rice–upland crop rotation commonly increased organic carbon stratification. • Terrain, climate, soil depth and inherent content also affected stratification. The stratification ratio (SR) is a good indicator of the quantitative evaluation of the soil nutrient variation with depth, which is inter-related with nutrient cycles and agricultural productivity. However, the effects of the parent material and cropping system on the SR of soil organic carbon (SOC) and total nitrogen (TN) have received little attention. The current study collected 444, 437, and 363 soil samples at the depths of 0–20, 20–40, and 40–60 cm, respectively, in subtropical southwest China, where the predominant parent materials are alluvial deposits, purple shales, and limestone and the cropping systems are rice–upland crop rotation, upland crop rotation, and rice monoculture. A two-way analysis of variance (two-way ANOVA) and a redundancy analysis (RDA) were applied to investigate the effects of the parent material, cropping system, topography, and climate on SOC and TN contents, and the corresponding SR (SR1, 0–20 cm:20–40 cm; SR2, 0–20 cm:40–60 cm). Results indicated that the parent material and cropping system were the main factors linked to the SR of the SOC and TN, whereas topography and climate seemed to have weaker effects on the SR in the agricultural landscape. Generally, alluvial deposit- and purple shale-derived soils presented higher SR than limestone-derived soils. Rice–upland crop rotation systems increased the SR compared to rice monoculture and upland crop rotation systems. Exceptions were observed in rice–upland crop rotation and rice monoculture systems under limestone. The study highlighted the efficient SR indicator in examining the SOC and TN depth distribution corresponding to the parent material and cropping system and is expected to provide valuable information regarding the optimization of the cropping pattern in different lithological regions, thereby enhancing agricultural productivity. [ABSTRACT FROM AUTHOR]

[Display omitted] • A novel SBR-UMSR process was constructed to treat manure-free piggery wastewater. • The front-end SBR functioned as a COD remover to get an effluent with a COD/TN ≤ 1. • Partial nitrification – anammox process was well performed in the back-end UMSR. • Effective synchronous removal of COD and TN was achieved in the combined process. • COD, NH 4 +-N and TN in effluent all well met the strict discharge standard of China. A novel combined sequencing batch reactor (SBR) – up-flow microaerobic sludge reactor (UMSR) process was developed to treat manure-free piggery wastewater characterized by low COD/TN ratio and high NH 4 +-N. The front-end SBR was designed to get an effluent with COD/TN ≤ 1 by removing COD, allowing the back-end UMSR to practice anammox for the simultaneous removal of TN and NH 4 +-N. Fed with the raw piggery wastewater, the combined SBR-UMSR process was started up at 27℃ with a reflux ratio of 15:1 in the UMSR. After 230-days running, the removal of COD, TN, and NH 4 +-N in the combined SBR-UMSR process reached 78.41%,85.05%, and 92.21%, respectively. 50.22% of COD in the wastewater was removed in the SBR, while 87.11% of NH 4 +-N and 79.69% of TN were removed in the UMSR. Stoichiometry and bacterial function analysis revealed that the partial nitrification – anammox process was the dominant nitrogen removal approach in the UMSR. [ABSTRACT FROM AUTHOR]

Abstract: Tinfoil manufacturing and electronic waste (e-waste) recycling remain rudimentary processes in Zhejing Province, China, which could account for elevated blood lead levels (BLLs) and health impacts on children. We assessed the potential health risks of lead in tinfoil manufacturing and e-waste recycling areas. 329 children in total aged 11–12 who lived in a tinfoil manufacturing area (Lanxi), an e-waste recycling area (Luqiao) and a reference area (Chun''an) were studied. Lead levels in children''s blood were determined by inductively coupled plasma mass spectrometer (ICP-MS). Blood urea nitrogen (BUN), serum creatinine, serum calcium, δ-Aminolaevulinic acid (δ-ALA) and intelligence quotient (IQ) were also measured. Geometric mean of BLLs in Lanxi, Luqiao and Chun''an were 8.11μg/dL, 6.97μg/dL, and 2.78μg/dL respectively, with 35.1%, 38.9% and 0% of children who had BLLs above 10μg/dL. The BLLs in exposed areas were much higher than those in the control area. Lanxi children had higher creatinine and calcium than Chun''an children, and Luqiao children had higher δ-ALA and lower calcium than Chun''an children. No significant differences of IQ were observed between Lanxi, Luqiao and Chun''an, however a negative relationship between BLLs and IQ was shown for the study children. The results indicated that lead pollution from e-waste recycling and tinfoil processing appears to be a potential serious threat to children''s health. [Copyright &y& Elsevier]