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Characterization of precipitation in the background of atmospheric pollutants reduction in Guilin: Temporal variation and source apportionment

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Journal of environmental Sciences 2020年第12期32卷 1-13页

作者： Ling Li Hong Li Liang Peng Yongshan Li Yi Zhou Fahe Chai Zhaoyu Mo Zhiming Chen Jingying Mao Wenxing Wang State Key Laboratory of environmental Criteria and Risk Assessment Chinese Research Academy of Environmental SciencesBeijing 100012China College of Chemistry and Chemical Engineering Southwest Petroleum UniversityChengdu 610500China Guilin environmental Monitoring Center Station Guilin 541002China Scientific research Academy of Guangxi environmental Protection Nanning 530022China institute of environmental and Climate research Jinan UniversityGuangzhou 511443China environmental research institute Shandong UniversityQingdao 266237China

Rainfall samples were collected from three observation sites in Guilin from 2013 to 2017, and the chemical composition characteristics of precipitation and the contribution made by different ion sources were analyzed when atmospheric pollutants levels were reduced. The results showed that acid gas emissions and atmospheric pollutant concentrations continued to decline during the study period. However, the change in the volume-weighted mean p H at the three sites suggested that acid rain pollution was not alleviated and began to deteriorate after 2015. The continuing downward trend for alkaline neutralizing ions(Ca^(2+), NH_4^+) in precipitation indicated that the reduction in alkaline neutralizing substances in the atmosphere was an important factor that led to the deterioration in acid rain across Guilin. The principal component analysis and spearman correlation analysis indicated five sources of ions in precipitation. Quantitative assessment of these five sources indicated that fossil fuel combustion contributed the most ions concentration in precipitation at the three sites, followed by agriculture, terrestrial(crustal) sources, marine sources, and biomass burning. Long-distance airflow might affect the acidity, the electrical conductivity(EC), and ion concentrations in precipitation across Guilin. The airflow trajectory from the west and southeast directions corresponded to higher acidity and ion concentrations. According to the current air pollution control strategy planned by Guilin, reducing atmospheric coarse particles and NH_3 at the same time may potentially lead to further deteriorations in acid rain contents. Therefore, Guilin needs to develop more reasonable pollution prevention measures that synergistically control atmospheric pollutants and acid rain pollution.

关键词： Precipitation chemistry Characterization Source contributions Synergistic control Guilin

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Nitrifiers activity and community characteristics under stress conditions in partial nitrification systems treating ammonium-rich wastewater

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Journal of environmental Sciences 2018年第11期30卷 1-8页

作者： Jia Miao Qidong Yin Tomoyuki Hori Tomo Aoyagi Hiroshi Habe Guangxue Wu Guangdong Province Engineering research Center for Urban Water Recycling and environmental Safety Graduate School at ShenzhenTsinghua University environmental Management research institute National Institute of Advanced Industrial Science and Technology(AIST)

Long-term exposure of nitrifiers to high concentrations of free ammonia （FA） and free nitrous add （FNA） may affect nitrifiers activity and nitrous oxide （N2O） emission. Two sequencing batch reactors （SBRs） were operated at influent ammonium nitrogen （NH4-N） concentrations of 800 mg/L （SBRH） and 33S mg/L （SBRL）, respectively. The NH4-N removal rates in SBRH and SBRL were around 2.4 and 1.0 g/L/day with the nitritation efficiencies of 99.3% and 95.7%, respectively. In the simulated SBR cycle, the N20 emission factors were 1.61% in SBRH and 2.30% in SBRL. N2O emission was affected slightly by FA with the emission factor of 0.22%-0.65%, while N2O emission increased with increasing FNA concentrations with the emission factor of 0.22%～3.96%. The dominant ammonia oxidizing bacteria （AOB） were Nitrosomonas spp. in both reactors, and their relative proportions were 38.89% in SBRH and 13.36% in SBRL. Within the AOB genus, a species （i.e., operational taxonomic unit [OTU] 76） that was phylogenetically identical to Nitrosomonas europaea accounted for 99.07% and 82.04% in SBRH and SBRL, respectively. Additionally, OTU 215, which was related to Nitrosomonas stercoris, accounted for 16.77% of the AOB in SBRL.

关键词： Ammonium-rich wastewater Free ammonia Free nitrous acid N2O emission Partial nitrification

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The role of GIS in Digital Earth education

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International Journal of Digital Earth 2008年第4期1卷 326-346页

作者： J.J.Kerski environmental Systems research institute BroomfieldColoradoUSA

A growing number of educators worldwide have become convinced that geotechnologiesincluding geographic information systems(GIS),global positioning systems(GPS),and remote sensingare key technologies to prepare students to be tomorrow’s decision *** with local,regional,and global issues of the 21st century requires people who think spatially and who can use *** educators teach geotechnologies as a discipline,emphasising *** educators use geotechnologies as a tool to teach content,such as geography,history,environmental studies,Earth Science,biology,mathematics,economics and other *** such as traffic,population growth,urban sprawl,energy,water,crime,human health,biodiversity and sustainable agriculture are growing in complexity,exist at every scale and increasingly affect people’s everyday *** of these issues has a spatial *** for geotechnology education include educational content standards,constructivism,the school-to-career movement,active learning,citizenship education,authentic practice and assessment,interdisciplinary education,community connections and a sustained,increasing demand for GIS *** Earth is an ideal framework for contextualising domains of *** Digital Earth community can have a significant impact on the growth of geotechnologies in education,and conversely,the growth of geotechnologies in education and society can foster the forward movement of Earth systems concepts.

关键词： digital earth and geotechnologies spatial thinking educational GIS digital earth and society

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Development of benthic macroinvertebrates sediment index(BSI) for bioassessment of freshwater sediment

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International Journal of Sediment research 2019年第4期34卷 368-378页

作者： Pil Jae Kim Jong Hyeon Lee In Ae Huh Dong Soo Kong Department of Life Science Kyonggi University environmental Health & Safety research institute EH R&C CO.Ltd. Water environmental Engineering research Division National Institute of Environmental Research

Sediment quality has been evaluated in a variety of ways since the early 1990 s in studies from Europe. In South Korea, most studies have used an indicator value for benthic macroinvertebrates based on water quality, not sediment quality. To date, few studies have examined the biological integrity of benthic macroinvertebrate communities in South Korea. In the current study, the tolerance valency and value in samples and the indicator weight values were measured for 43 benthic macroinvertebrate taxa from 73 sampling units in South Korea from 2014 to 2016. Total organic carbon, the amount of heavy metals, and total ammonia nitrogen were analyzed. The average grade for each pollutant was used as the sediment quality index. A benthic macroinvertebrates sediment index was developed for bioassessment of freshwater sediment. The benthic macroinvertebrates sediment index, which is based on the relative frequency of occurrence of macroinvertebrates, was highly correlated with pollution levels in the sediment. This index can be used in the field to assess the contamination of freshwater sediment. As the sample size was small in the current study and there were taxonomic limitations of Chironomidae larvae,further research is needed to improve the reliability of the benthic macroinvertebrates sediment index.

关键词： Benthic macroinvertebrates Bioassessment Freshwater sediment Sediment quality index

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Study of charge structure and radiation characteristic of intracloud discharge in thunderstorms of Qinghai-Tibet Plateau

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Science China Earth Sciences 2004年第z1期47卷 108-114页

作者： ZHAGN Yijun DONG Wansheng ZHAO Yang ZHANG Guangshu ZHANG Hongfa CHEN Chengpin ZHANG Tong Cold and Arid Regions environmental and Engineering research institute Chinese Academy of Sciences Lanzhou 730000 China Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China

The comprehensive observations on lightning discharges were conducted in Naqu area of Qinghai-Tibet Plateau in summer of 2002. The electric structures of thunderstorms and the characteristics of lightning discharges at initial stage were analyzed by using the observation data. The results show that most of intracloud (IC) lightning flashes were polarities inverted in thunderstorms with tripole electric charge structure and occurred between negative charge region located in the middle of the thunderstorm and positive charge region located at the bottom of the thunderstorm. The radiation characteristics of discharge processes in cloud with longer lasting time involved in Cloud-to-Ground (CG) lightning flashes were similar to that of IC discharges.A lot of radiation pulses were produced in these discharge processes. Because the IC discharges took place at the bottom of thundercloud and were near the ground, they may produce more serious damage to equipment on the ground therefore should not be neglected in lightning protection.

关键词： Qinghai-Tibet Plateau, characteristics of lightning discharges, charge structure of thunderstorm.

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Improvement of Surface Albedo Simulations over Arid Regions

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Advances in Atmospheric Sciences 2008年第3期25卷 481-488页

作者：鲍艳吕世华张宇孟宪红杨胜朋 Cold and Arid Regions environmental and Engineering research institute Chinese Academy of Sciences Cold and Arid Regions environmental and Engineering research institute Chinese Academy of SciencesLanzhou 730000

To improve the simulation of the surface radiation budget and related thermal processes in arid regions, three sophisticated surface albedo schemes designed for such regions were incorporated into the Biosphere- Atmosphere Transfer Scheme （BATS）. Two of these schemes are functions of the solar zenith angle （SZA）, where the first one has one adjustable parameter defined as SZA1 scheme, and the second one has two empirical parameters defined as SZA2 scheme. The third albedo scheme is a function of solar angle and soil water that were developed based on arid-region observations from the Dunhuang field experiment （DHEX）（defined as DH scheme）. We evaluated the performance of the original and newly-incorporated albedo schemes within BATS using the in-situ data from the Oasis System Energy and Water Cycle Field Experiment that was carried out in JinTa, Gansu arid area （JTEX）. The results indicate that a control run by the original version of the BATS generates a constant albedo, while the SZA1 and SZA2 schemes basically can reproduce the observed diurnal cycle of surface albedo, although these two schemes still underestimate the albedo when SZA is high in the early morning and late afternoon, and overestimate it when SZA is low during noontime. The SZA2 scheme has a better overall performance than the SZA1 scheme. In addition, BATS with the DH scheme slightly improves the albedo simulation in magnitude as compared to that from the control run, but a diurnal cycle of albedo is not produced by this scheme. The SZA1 and SZA2 schemes significantly increase the surface absorbed solar radiation by nearly 70 W m^-2, which further raises the ground temperature by 6 K and the sensible heat flux by 35 W m^-2. The increased solar radiation, heat flux, and temperature are more consistent with the observations that those from the control run. However, a significant improvement in these three variables is not found in BATS with the DH scheme due to the neglect of the diurnal cycle of a

关键词： arid region bare soil surface albedo solar zenith angle (SZA) BATS

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Syntheses and fluorescent properties of complexes of Eu(Ⅲ) with HTTA,TPPO and benzoic acid

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Journal of Rare Earths 2009年第3期27卷 369-372页

作者：湛雪辉肖忠良湛含辉赵学辉周随安李飞 Chemical and environmental Engineering School Changsha Science and Technical University environmental Protection research institute Hunan University of Technology

A series of Eu（III） complexes of α-thenoyltrifluoroacetone（HTTA） with trioctylphosphine oxide（TPPO） and benzoic acid（BA） or its two derivatives, p-toluic acid（PTA） and p-methoxybenzoic acid（POA） were synthesized and were characterized with elemental analysis, IR spectroscopy, scanning electronic microscopy and fluorescent spectra. The complexes were revealed to be Eu（BA）（TTA）2TPPO2, Eu（PTA）（TTA）2TPPO2 and Eu（POA）（TTA）2TPPO2. The excitation and absorption spectra of the complex Eu（POA）（TTA）2TPPO2 in MeOH solution were investigated in detail. The experimental result showed that relatively cheap materials with sharp red luminescence could be prepared, when benzoic acid or its two derivatives were added in Eu（III） complexes of ct-thenoyltrifluoroacetone with trioctylphosphine oxide. The relative fluorescence intensity of the Eu（III） complexes decreased in the following order： Eu（POA）（TrA）2TPPO2〉 Eu（PTA）（TTA）ETPPO2〉Eu（BA）（TFA）2TPPO2.

关键词： fluorescent nrooerties: euronium: benzoic acid: α-thenovltnfluoroacetone: rare earths

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Validity of a noninvasive estimation of deep body temperature when wearing personal protective equipment during exercise and recovery

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Military Medical research 2019年第4期6卷 328-339页

作者： Andrew P.Hunt Mark J.Buller Matthew J.Maley Joseph T.Costello Ian B.Stewart School of Exercise and Nutrition Sciences&institute of Health and Biomedical Innovation Queensland University of TechnologyBrisbaneQLDAustralia United States army research institute of environmental medicine NatickMAUSA Extreme Environments Laboratory Department of Sport and Exercise ScienceUniversity of PortsmouthPortsmouthUK

Background:Deep body temperature is a critical indicator of heat ***,direct measures are often invasive,costly,and difficult to implement in the *** study assessed the agreement between deep body temperature estimated from heart rate and that measured directly during repeated work bouts while wearing explosive ordnance disposal(EOD)protective clothing and during ***:Eight males completed three work and recovery periods across two separate *** consisted of treadmill walking on a 1%incline at 2.5,4.0,or 5.5 km/h,in a random order,wearing EOD protective *** temperature and relative humidity were maintained at 24℃and 50%[Wet bulb globe temperature(WBGT)(20.9±1.2)℃]or 32℃and 60%[WBGT(29.0±0.2)℃]on the separate days,*** rate and gastrointestinal temperature(TGI)were monitored continuously,and deep body temperature was also estimated from heart rate(ECTemp).Results:The overall systematic bias between TGI and ECTemp was 0.01℃with 95%limits of agreement(Lo A)of±0.64℃and a root mean square error of 0.32℃.The average error statistics among participants showed no significant differences in error between the exercise and recovery periods or the environmental *** TGI levels of(37.0–37.5)℃,(37.5–38.0)℃,(38.0–38.5)℃,and>38.5℃,the systematic bias and±95%Lo A were(0.08±0.58)℃,(–0.02±0.69)℃,(–0.07±0.63)℃,and(–0.32±0.56)℃,***:The findings demonstrate acceptable validity of the ECTemp up to 38.5℃.Conducting work within an ECTemp limit of 38.4℃,in conditions similar to the present study,would protect the majority of personnel from an excessive elevation in deep body temperature(>39.0℃).

关键词： Protective clothing Body core temperature Heat strain Heat stress Kalman filter Explosive ordnance disposal

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Impact of climate change on hydropower generation in Rio Jubones Basin, Ecuador

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Water Science and Engineering 2018年第2期11卷 157-166页

作者： Mohammad Mehedi Hasan Guido Wyseure Hydraulic research Directorate River Research Institute Department of Earth and environmental Sciences KU Leuven

This study attempted to use the soil and water assessment tool(SWAT), integrated with geographic information systems(GIS), for assessment of climate change impacts on hydropower generation. This methodology of climate change impact modeling was developed and demonstrated through application to a hydropower plant in the Rio Jubones Basin in Ecuador. ArcSWAT 2012 was used to develop a model for simulating the river flow. The model parameters were calibrated and validated on a monthly scale with respect to the hydro-meteorological inputs observed from 1985 to 1991 and from 1992 to 1998, respectively. Statistical analyses produced Nash-Sutcliffe efficiencies(NSEs) of 0.66 and 0.61 for model calibration and validation, respectively, which were considered acceptable. Numerical simulation with the model indicated that climate change could alter the seasonal flow regime of the basin, and the hydropower potential could change due to the changing climate in the *** analysis indicates that, though the hydropower generation will increase in the wet season, the plant will face a significant power shortage during the dry season, up to 13.14% from the reference scenario, as a consequence of a 17% reduction of streamflow under an assumption of a 2.9℃ increase in temperature and a 15% decrease in rainfall. Overall, this study showed that hydrological processes are realistically modeled with SWAT and the model can be a useful tool for predicting the impact of climate change.

关键词： SWAT Hydropower generation Climate change Sensitivity analysis Nash-Sutcliffe efficiency(NSE)

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Distribution of methylsiloxanes in benthic mollusks from the Chinese Bohai Sea

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Journal of environmental Sciences 2019年第2期31卷 199-207页

作者： Liqin Zhi Lin Xu Xudan He Chunhui Zhang Yaqi Cai State Key Laboratory of environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental ScienceChinese Academy of Sciences University of Chinese Academy of Sciences environmental Protection research institute of Light Industry School of Chemical & environmental Engineering China University of Mining & Technology(Beijing) institute of Environment and Health Jianghan University

Methylsiloxanes are a class of silicone compounds that have been widely used in various industrial processes and personal care products for several decades. This study investigated the spatial distribution of three cyclic methylsiloxanes(D4–D6) and twelve linear methylsiloxanes(L5–L16) in mollusks collected from seven cities along the Bohai Sea. D4–D6(df = 71%–81%) and L8–L16(df = 32%–40%) were frequently detectable in the mollusk samples, while L5–L7 were not found in any mollusk samples. Cyclic methylsiloxanes(D4–D6) were found in mollusks with the mean concentrations of 15.7 ± 12.3 ng/g ww for D4,24.6 ± 15.8 ng/g ww for D5 and 34.0 ± 23.0 ng/g ww for D6. Among the seven sampling cities, the cyclic methylsiloxanes were predominant in mollusks, with the total cyclic methylsiloxanes(sum of D4–D6, ∑ CMS) accounting for 74.2%–80.7% of the total methylsiloxanes. ∑ CMS along the coastline demonstrated a clear gradient, with the highest concentrations in mollusks at the sampling sites located in the western part of the Bohai Sea and the lowest concentrations in mollusks from cities located in the eastern part of the Bohai Sea. The biota-sediment accumulation factors for cyclic methylsiloxanes(D4–D6) and linear methylsiloxanes(L8–L16) were estimated as 0.42 ± 0.06–0.53 ± 0.06 and0.13 ± 0.03–0.19 ± 0.05, respectively.

关键词： Methylsiloxane Mollusks Sediment Bioaccumulation

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