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The beryllium-7(7Be) tracer technique is an important complement to radioactive tracer techniques using 137Cs and 210Pb, which is specifically used to determine the short-term soil erosion rate. This paper reports a new model for radionuclide measurements to estimate soil redistribution for use with 7Be measurements. The approach was successfully tested from a study of short-term soil redistribution undertaken on two selected sloping sites. The estimates of soil redistribution obtained using the 7Be model were consistent with those obtained from erosion pins deployed within the same study area. The results confirm the potential for using 7Be to document soil erosion. [ABSTRACT FROM AUTHOR]

This study concentrated on the pollution level, sources, and lung cancer risk of PM10-bound polycyclic aromatic hydrocarbons (PAHs) in summer in Nanjing, China. PM10 samples were collected in summer of the year 2015 in Nanjing. 16 USEPA (United States Environmental Protection Agency) priority PAHs were extracted and analyzed after sampling. The mean concentrations of PAHs and BaPeq were 7.49±2.60 and 1.21±0.24 ng/m3, respectively, being in a middle level among results from regions worldwide. According to the results of diagnostic ratios, PAHs originated mainly from traffic exhaust, especially diesel vehicle emissions. Owing to the inhalation exposure, the median values of incremental lung cancer risk (ILCR) were estimated to be 3.36×10-8, 2.50×10-8, 1.69×10-7, 2.54×10-8, 1.38×10-7, 1.18×10-7, 1.27×10-7, and 1.11×10-7 for boys, male adolescents, male adults, male seniors, girls, female adolescents, female adults, and female seniors, respectively, indicating low potential lung cancer risk. [ABSTRACT FROM AUTHOR]

Abstract: This paper deals with the international meteorological and hydrological training issue and its evaluation approach based on the teaching practice and experience during last twenty years at World Meteorological Organization Regional Training Centre (WMO RTC) in Nanjing. The success of the training courses which are organized by the RTC Nanjing in the framework of Guidelines for the Education and Training of Personnel in Meteorology and Operational Hydrology (WMO- No. 258) has been widely recognized by those countries which benefit from the training programs as well as the WMO and other related international organizations. The design of the training syllabuses fulfils the Member''s training requirements of WMO. Some new training courses which reflect the advances in meteorology and hydrology have also been offered in order to enhance the capabilities of trainees in the use of the up-to-date numerical products. In addition to face-to-face teaching, blended learning has been introduced for some training courses to enhance the training efficiency. Based on the “CIPP model” and “Kirkpatrick Four Levels Model”, a more efficient evaluation system for the international meteorological and hydrological training has been established. Results show that this evaluation system is capable of assessing the training target, the training results as well as training itself. The evaluation index system consists of six indices which focus on the training subjects and trainees, respectively. The application of this evaluation system in the international meteorological and hydrological training has significantly improved the training efficiency and training itself at RTC Nanjing. [Copyright &y& Elsevier]

This paper focused on the pollution characteristics, sources and lung cancer risk of atmospheric polycyclic aromatic hydrocarbons (PAHs) in a new urban district of Nanjing, China. Gaseous and aerosol PM 2.5 (particulate matter with aerodynamic diameter smaller than 2.5 μm) samples were collected in spring of 2015. Sixteen PAHs were extracted and analyzed after sampling. Firstly, arithmetic mean concentrations of PAHs and BaP eq (benzo[a]pyrene equivalent) were calculated. The mean concentrations of PAHs were 29.26 ± 14.13, 18.14 ± 5.37 and 48.47 ± 16.03 ng/m 3 in gas phase, particle phase and both phases, respectively. The mean concentrations of BaP eq were 0.87 ± 0.51, 2.71 ± 2.17 and 4.06 ± 2.31 ng/m 3 in gas phase, particle phase and both phases, respectively. Secondly, diagnostic ratios and principal component analysis were adopted to identify the sources of PAHs and the outcomes were the same: traffic exhaust was the predominant source followed by fuel combustion and industrial process. Finally, incremental lung cancer risk (ILCR) induced by whole year inhalation exposure to PAHs for population groups of different age and gender were estimated based on a Monte Carlo simulation. ILCR values caused by particle phase PAHs were greater than those caused by gas phase PAHs. ILCR values for adults were greater than those for other age groups. ILCR values caused by total (gas + particle) PAHs for diverse groups were all greater than the significant level (l0 − 6 ), indicating high potential lung cancer risk. Sensitivity analysis results showed that cancer slope factor for BaP inhalation exposure and BaP eq concentration had greater impact than body weight and inhalation rate on the ILCR. [ABSTRACT FROM AUTHOR]

Dissolved organic matter (DOM) is a ubiquitous group of organic compounds in rainwater that plays vital roles in the biogeochemical cycle. However, little is known about its chemical composition, optical characterization, potential sources, and controlling mechanisms in peri-urban atmospheric rainwater. One-year rainfall samples were collected between September 2018 and August 2019 in a Nanjing suburb. Stoichiometric, ultraviolet–visible (UV–Vis) absorption, and three-dimensional fluorescence excitation-emission matrix (EEM) with parallel factor analysis (PARAFAC) analyses were utilized to characterize DOM. Several proxies for DOM concentration, including dissolved organic carbon (DOC), dissolved organic nitrogen (DON), and absorption coefficient (a254), exhibited power-function relationships with the rainfall amount (r2 = 0.33–0.55, p < 0.001). Particularly, the DOC and a254 value showed significant seasonal variability, with lower value in two wet seasons (winter and summer) than in the dry seasons (autumn and spring). The annual wet depositional (WD) flux of DOC in the Xianlin (XL) site was calculated as 1.68 g C m−2 yr−1, agreeing with the range of global WD flux values. Two terrestrial humic-like components (C1–C2), one microbial humic-like component (C3), and one tryptophan-like component (C4) were identified by EEM-PARAFAC in rainwater DOM. The results of the specific absorption indices (SUVA 254, S R) and PARAFAC component analyses revealed that summer DOM samples had lower fluorescence intensities, aromatic contents, and molecular sizes. Principal component analysis (PCA) based on DOM indices showed that rainwater DOM had predominantly terrestrial humic origins, while this characteristic became slightly weaker in summer. The quantity and quality of rainwater DOM were closely related to meteorological variables (i.e., air mass, rainfall amount, and solar radiation) as well as anthropogenic activities. This study could improve the understanding of the quantity and quality of rainwater DOM on carbon budgets and biogeochemical cycling from some new insights of optical proxies about different fates of rainwater DOM under complex controlling mechanisms. Image 1 • Concentration and chemical structure of rainwater DOM showed seasonal variations. • Climatic factors and human activities were dominant effects on rainwater DOM. • Rainwater DOM components were mainly generated from humic substances. • Wet inorganic N in atmosphere was closely coupled with rainwater DOM. [ABSTRACT FROM AUTHOR]