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Geographic distribution of arsenic contamination in the Himalayan Rivers flowing through Pakistan: Implications for its natural source and effects of anthropogenic activities

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International Journal of Sediment Research 2023年第4期38卷 543-555页

作者： Ishtiaque Hussain Hafiz Ur.Rehman Takaaki Itai Junaid Ali Khattak Abida Farooqi environmental Geochemistry Laboratory Department of Environmental Sciences Faculty of Biological Sciences Quaid-i-Azam University Department of environmental sciences University of Baltistan Skardu graduate school of sciences and Engineering Kagoshima University Department of Earth and Planetary environmental science (UG) Graduate School of Science The University of Tokyo Department of Earth and Planetary Physics (UG) Graduate School of Science The University of Tokyo Department of Earth and Planetary science (GR) Graduate School of Science The University of Tokyo

Arsenic(As) in natural hydrological systems is known as a worldwide major environmental concern. A geochemical and sedimentological study was done to ascertain the origin and geographical distribution of As in surface water and fluvial sediment collected from the floodplains/basins of the River Indus and its four major tributaries that drain through the northern Pakistan. The hydrogeochemical compositions of all five rivers were similar with calcium(Ca2+) and bicarbonate(HCO3-) being the dominating ions. The concentration of As ranged from 0.62-24.05 μg/L(average 3.7 ± 3.5 μg/L, n = 61) in river water, 2.3-23.4 mg/kg(average 5.7 ± 3.9 mg/kg) in suspended sediment, and 2.0-13 mg/kg(average4.13 ± 2.3 mg/kg) in fluvial sediment. Various approaches were used, including mineralogical, sequential extraction, geochemical, and statistical analyses to investigate the distribution, behavior, and potential sources of As in the sediment. The effect of geological factors on the distribution of As was also studied.No noticeable changes in the relative abundance of minerals were observed in the sediment at different locations along the river. Both mineralogical and statistical analyses showed that silicate minerals like muscovite, biotite, and chloride are the main As reservoir while oxides minerals like hematite and magnetite, which are minor components in the sediment are second largest As carrier. A geochemical baseline, using the normalization and cumulative frequency distribution curves was constructed for As.The estimated mean human contribution of As was 3.4% in the Indus River, 1.9% in the Jhelum River, 13.7%in the Chenab River, 17.5% in the Ravi River and 5.4% in the Sutlej River, indicating relatively higher effects of anthropogenic activity along the Chenab River and Ravi River. The almost negligible effects of anthropogenic activities were additionally confirmed through the pollution assessment parameters estimated from the geo-enrichment, contamination factors, and accumulation index analyses. The current data sugg

关键词： Arsenic Indus basin Geochemical baseline Source Contamination assessment

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Response surface method for modeling the removal of carbon dioxide from a simulated gas using water absorption enhanced with a liquid-film-forming device

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Journal of environmental sciences 2018年第3期30卷 116-126页

作者： Diem-Mai Kim Nguyen Tsuyoshi Imai Thanh-Loc Thi Dang Ariyo Kanno Takaya Higuchi Koichi Yamamoto Masahiko Sekine Graduate School of Environmental Sciences and Engineering Yamaguchi University graduate school of sciences and Technology for Innovation Yamaguchi University Department of environmental science College of Sciences Hue University

This paper presents the results from using a physical absorption process to absorb gaseous CO2mixed with N2using water by producing tiny bubbles via a liquid-film-forming device（LFFD）that improves the solubility of CO2in water.The influence of various parameters—pressure,initial CO2concentration,gas-to-liquid ratios,and temperature—on the CO2removal efficiency and its absorption rate in water were investigated and estimated thoroughly by statistical polynomial models obtained by the utilization of the response surface method（RSM）with a central composite design（CCD）.Based on the analysis,a high efficiency of CO2capture can be reached in conditions such as low pressure,high CO2concentration at the inlet,low gas/liquid ratio,and low temperature.For instance,the highest removal efficiency in the RSM–CCD experimental matrix of nearly 80%occurred for run number 20,which was conducted at 0.30 MPa,CO2concentration of 35%,gas/liquid ratio of 0.71,and temperature of 15℃.Furthermore,the coefficients of determination,R^2,were 0.996 for the removal rate and 0.982 for the absorption rate,implying that the predicted values computed by the constructed models correlate strongly and fit well with the experimental values.The results obtained provide essential information for implementing this method properly and effectively and contribute a promising approach to the problem of CO2capture in air pollution treatment.

关键词： Carbon dioxide Water dissolution Liquid-film Response surface method （RSM）

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Effect of Intertidal Elevation at Tsuyazaki Cove,Fukuoka,Japan on Survival Rate of Horseshoe Crab Tachypleus tridentatus Eggs

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Journal of Ocean University of China 2022年第3期21卷 601-610页

作者： ITAYA Shinji SHUUNO Mari ONIKURA Norio TAI Akira YANO Shinichiro environmental Fluid Dynamics Laboratory Department of Urban and Environmental EngineeringGraduate School of EngineeringKyushu UniversityFukuoka819-0395Japan Tsuyazaki Seaside Nature school Fukutsu811-3304Japan Fishery Research Laboratory Department of Bioresource ScienceGraduate School of Bioenvironmental ScienceKyushu UniversityFukuoka819-0395Japan

Physical factors affecting the survival of Tachypleus tridentatus eggs were investigated by translocating their eggs between the high intertidal zone and the low intertidal zone of a known spawning site.The mean egg survival rates per day were highest in the mid intertidal zone(45.1%±25.4%)and the lowest in the low intertidal zone(13.3%±27.6%).Differences in the elevation,air exposure time,and water content of the spawning ground were significant factors determining the egg survival rates.Excessive or insufficient air exposure time resulted in inadequate water content at higher and lower intertidal zones and could reduce egg survival.On the other hand,moderate saturation and dehydration were repeated with each tidal movement in the mid intertidal zone.This dynamic is considered as one of the crucial factors for the survival of eggs and is considered optimal for spawning.Therefore,the protection of the mid intertidal zone is imperative for maximizing the egg survival rate in Tsuyazaki Cove where almost all suitable nesting sites have disappeared due to coastal development.By protecting these optimal sites for spawning and recovering other optimal sites on suitable beaches,a positive contribution can be made to future management and conservation.The study also suggests that translocating eggs from marginal to optimal spawning sites might be a recovery strategy for this globally endangered species.

关键词： air exposure time globally endangered species intertidal elevation intertidal zone optimal spawning site Tachypleus tridentatus translocated horseshoe crab eggs Tsuyazaki Cove

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Relationship between PM_(10) and PM_(2.5) levels in high-traffic area determined using path analysis and linear regression

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Journal of environmental sciences 2018年第7期30卷 105-114页

作者： Narut Sahanavin Tassanee Prueksasit Kraichat Tantrakarnapa Interdisciplinary Program of environmental science Graduate School Chulalongkorn University Department of environmental science Faculty of Science Chulalongkorn University Department of Social and environmental Medicine Faculty of Tropical Medicine Mahidol University

The objective of this study was to determine the relationship between PM10 and PM2.5 levels as related to meteorological conditions and traffic flow using both a linear regression analysis and a path analysis. The Particulate matter（PM） samples were collected from Sukhumvit road, Bangkok, Thailand, at both open（104 samples） and covered（92 samples）areas along the road. Fifteen percent of all samples were separated before the statistical models were run and used for model validation. The results from the path analysis were more elaborate than those from the linear regression, thus indicating that meteorological conditions had a direct effect on the particulate levels and that the effects of traffic flow were more variable in open areas. The model also indicated that meteorological conditions had an indirect effect and that traffic flow had a direct effect on particulate levels in covered areas. The model validation results indicated that for open areas, the R^2 values were not very different between the path analysis and the linear regression model, but that the path analysis was more accurate than the linear regression model at very low PM concentrations. At high PM concentrations, the path analysis model also had a better fit than did the linear regression, so the predictions from the path analysis model were more accurate than those from the linear regression.

关键词： Path analysis PM10 PM2.5 Open roadside area Covered roadside area

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Characterizing oxygenated volatile organic compounds and their sources in rural atmospheres in China

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Journal of environmental sciences 2019年第7期31卷 148-155页

作者： Yu Han Xiaofeng Huang Chuan Wang Bo Zhu Lingyan He Key Laboratory for Urban Habitat environmental science and Technology School of Environment and Energy Peking University Shenzhen Graduate School

Oxygenated volatile organic compounds(OVOCs) are important precursors and products of atmospheric secondary pollution. The sources of OVOCs, however, are still quite uncertain,especially in the atmosphere with much pollution in China. To study the sources of OVOCs in rural atmospheres, a proton transfer reaction mass spectrometry(PTR-MS) was deployed at a northern rural site(WD) and a southern rural site(YMK) in China during the summer of 2014 and 2016, respectively. The continuous observation showed that the mean concentration of TVOCs(totally 17 VOCs) measured at WD(52.4 ppbv) was far higher than that at YMK(11.1 ppbv), and the OVOCs were the most abundant at both the two sites. The diurnal variations showed that local sources of OVOCs were still prominent at WD, while regional transport influenced YMK much. The photochemical age-based parameterization method was then used to quantitatively apportion the sources of ambient OVOCs. The anthropogenic primary sources at WD and YMK contributed less(2%–16%) to each OVOC species. At both the sites, the atmospheric background had a dominant contribution(～ 50%) to acetone and formic acid, while the anthropogenic secondary formation was the main source(～ 40%) of methanol and MEK. For acetaldehyde and acetic acid, the biogenic sources were their largest source(～ 40%) at WD, while the background(39%) and anthropogenic secondary formation(42%) were their largest sources at YMK, respectively. This study reveals the complexity of sources of OVOCs in China, which urgently needs explored further.

关键词： OVOCs Photochemical age Anthropogenic sources Primary emission Secondary formation

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Understanding primary and secondary sources of ambient oxygenated volatile organic compounds in Shenzhen utilizing photochemical age-based parameterization method

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Journal of environmental sciences 2019年第1期31卷 105-114页

作者： Bo Zhu Yu Han Chuan Wang Xiaofeng Huang Shiyong Xia Yingbo Niu Zixuan Yin Lingyan He Key Laboratory for Urban Habitat environmental science and Technology School of Environment and Energy Peking University Shenzhen Graduate School

Oxygenated volatile organic compounds(OVOCs) are key intermediates in the atmospheric photooxidation process. To further study the primary and secondary sources of OVOCs,their ambient levels were monitored using a proton-transfer reaction mass spectrometer(PTR-MS) at an urban site in the Pearl River Delta of China. Continuous monitoring campaigns were conducted in the spring, summer, fall, and winter of 2016. Among the six types of OVOC species, the mean concentrations of methanol were the highest in each season(up to 13–20 ppbv), followed by those of acetone, acetaldehyde and acetic acid(approximately 2–4 ppbv), while those of formic acid and methyl ethyl ketone(MEK) were the lowest(approximately 1–2 ppbv). As observed from a diurnal variation chart, the OVOCs observed in Shenzhen may have been affected by numerous factors such as their primary and secondary sources and photochemical consumption. The photochemical age-based parameterization method was used to apportion the sources of ambient OVOCs. Methanol had significant anthropogenic primary sources but negligible anthropogenic secondary sources during all of the seasons. Acetone, MEK and acetic acid were mostly attributed to anthropogenic primary sources during each season with smaller contributions from anthropogenic secondary sources. Acetaldehyde had similar contributions from both anthropogenic secondary and anthropogenic primary sources throughout the year.Meanwhile, anthropogenic primary sources contributed the most to formic acid.

关键词： OVOCs PTR-MS Photochemical age-based parameterization method

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environmental arsenic(As)and its potential relationship with endemic disease in southwestern China

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Journal of environmental sciences 2024年第5期139卷 46-59页

作者： Donglin Li Hucai Zhang Fengqin Chang Lizeng Duan Yang Zhang Institute for Ecological Research and Pollution Control of Plateau Lakes School of Ecology and Environmental ScienceYunnan UniversityKunming 650500China Southwest United graduate school Kunming 650500China

Many cases of an unknown disease exhibiting the clinical features of limb gangrene,blisters,ulceration,and exfoliation have been reported in Daping village(DV)in southwestern China.However,the pathogenesis is unknown and has puzzled doctors for many years.A preliminary study on heavy metals and symptoms indicated that arsenic might pose the greatest threat to the health of local residents.Here,to explore the sources of and factors influencing arsenic enrichment in DV,whose residents exhibit signs of arsenic poisoning,the As contents in soil,water,and plants were systematically measured.The results indicated high As contents in plant and soil samples obtained from the area,and the source of As may be linked to the weathering of black shale rock.Ingestion of soil and consumption of plants were the two main As exposure pathways among children and adults,respectively,and children exhibited a higher health risk than adults.We presume and emphasize that when extreme drought events occur,humans might face unusual risks resulting from exposure to toxic elements and the direct consumption of highly polluted water.Our study provides a new perspective and sheds light on the environmental geochemistry and health links of this disease.

关键词： Endemic disease Arsenic(As) Risk assessment Black shale Climate change

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Development of an on-line measurement system for water-soluble organic matter in PM_(2.5) and its application in China

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Journal of environmental sciences 2018年第7期30卷 33-40页

作者： Huiying Li Xiaofeng Huang Liming Cao Yuhong Zhai Liwu Zeng Lingyan He Key Laboratory for Urban Habitat environmental science and Technology School of Environment and Energy Peking University Shenzhen Graduate School

Water-soluble organic matter（WSOM） represents a critical fraction of fine particles（PM2.5）in the air, but its changing behaviors and formation mechanisms are not well understood yet, partly due to the lack of fast techniques for the ambient measurements. In this study,a novel system for the on-line measurement of water-soluble components in PM2.5, the particle-into-liquid sampler（PILS）–Nebulizer–aerosol chemical speciation monitor（ACSM）, was developed by combining a PILS, a nebulizer, and an ACSM. High time resolution concentrations of WSOM, sulfate, nitrate, ammonium, and chloride, as well as mass spectra, can be obtained with satisfied quality control results. The system was firstly applied in China for field measurement of WSOM. The mass spectrum of WSOM was found to resemble that of oxygenated organic aerosol, and WSOM agreed well with secondary inorganic ions. All evidence collected in the field campaign demonstrated that WSOM could be a good surrogate of secondary organic aerosol（SOA）. The PILS–Nebulizer–ACSM system can thus be a useful tool for intensive study of WSOM and SOA in PM2.5.

关键词： PM2.5 Water-soluble organic matter Secondary organic matter On-line measurement Mass spectrum

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Involvement of A5/A7 noradrenergic neurons and B2 serotonergic neurons in nociceptive processing:a fiber photometry study

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Neural Regeneration Research 2022年第4期17卷 881-886页

作者： Shunpei Moriya Akira Yamashita Daiki Masukawa Junichi Sakaguchi Yoko Ikoma Yoshimune Sameshima Yuki Kambe Akihiro Yamanaka Tomoyuki Kuwaki Department of Physiology Kagoshima University Graduate School of Medical and Dental ScienceKagoshimaJapan Department of Molecular Pharmacologyand Neurobiology Yokohama City University Graduate School of MedicineYokohamaJapan Department of Pharmacology Kagoshima University Graduate School of Medical and Dental ScienceKagoshimaJapan Research Institute of environmental Medicine Nagoya UniversityNagoyaJapan

In the central nervous system,the A6 noradrenaline(NA)and the B3 serotonin(5-HT)cell groups are well-recognized players in the descending antinociceptive system,while other NA/5-HT cell groups are not well characterized.A5/A7 NA and B25-HT cells project to the spinal horn and form descending pathways.We recorded G-Ca MP6 green fluorescence signal intensities in the A5/A7 NA and the B25-HT cell groups of awake mice in response to acute tail pinch stimuli,acute heat stimuli,and in the context of a non-noxious control test,using fiber photometry with a calcium imaging system.We first introduced G-Ca MP6 in the A5/A7 NA or B25-HT neuronal soma,using transgenic mice carrying the tetracycline-controlled transactivator transgene under the control of either a dopamineβ-hydroxylase or a tryptophan hydroxylase-2 promoters and by the site-specific injection of adeno-associated virus(AAV-Tet O(3 G)-G-Ca MP6).After confirming the specific expression patterns of G-Ca MP6,we recorded G-Ca MP6 green fluorescence signals in these sites in awake mice in response to acute nociceptive stimuli.G-Ca MP6 fluorescence intensity in the A5,A7,and B2 cell groups was rapidly increased in response to acute nociceptive stimuli and soon after,it returned to baseline fluorescence intensity.This was not observed in the non-noxious control test.The results indicate that acute nociceptive stimuli rapidly increase the activities of A5/A7 NA or B25-HT neurons but the non-noxious stimuli do not.The present study suggests that A5/A7 NA or B25-HT neurons play important roles in nociceptive processing in the central nervous system.We suggest that A5/A7/B2 neurons may be new therapeutic targets.All performed procedures were approved by the Institutional Animal Use Committee of Kagoshima University(MD17105)on February 22,2018.

关键词： A5 NA neurons A7 NA neurons B25-HT neurons DBH-tTA mice fiber photometry G-CaMP6 mCherry monoaminergic signaling nociception TPH-t TA mice

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Regional management and biodiversity conservation in GIAHS:text analysis of municipal strategy and tourism management

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Ecosystem Health and Sustainability 2019年第1期5卷 124-132,I0019页

作者： Ryo Kohsaka Hikaru Matsuoka Yuta Uchiyama Marie Rogel graduate school of environmental Studies Nagoya UniversityNagoyaJapan Institute of science and Engineering Kanazawa UniversityKanazawaJapan graduate school of environmental Studies Tohoku UniversitySendaiJapan

Purpose of the research:To identify the gaps between the rhetoric and reality of the role of citizen participation and its role in maintenance and monitoring of heritages and resources(including biodiversity monitoring),we analyzed the discourse of Globally Important Agricultural Heritage System(GIAHS)at municipality level.Methods:As an analytical framework,text mining is applied to interviews of officers at the municipal level of GIAHS in Noto which was amongst the first sites in Japan.The identification of such gap is critical for sustainability and to prevent conflicts from tourism,agriculture or educations.Results:The results reveal that(1)there is a gap between the official goals of that designation at the international level and local needs,(2)role of citizens is emphasized in the applications and action plans at rhetorical level but remain rather limited in practice and that(3)municipalities composing the GIAHS often have different priorities,even within the very same GIAHS sites,some municipalities even calling themselves“just a transition point to other destination municipalities.”Conclusions:It is critical for municipal officers to collaborate with various stakeholders,especially citizens.As such,citizen science is a bottom-up approach to promote biodiversity conservation and facilitate GIAHS managements.

关键词： Municipality global institution GIAHS text mining co-occurrence analysis correspondence analysis

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