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Evaluation of phosphorus bioavailability in El Mex Bay and Lake Mariut sediments

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International Journal of Sediment Research 2017年第3期32卷 432-441页

作者： Naglaa F.Soliman Gehan M.El Zokm Mohamed A.Okbah Department of environmental studies Institute of Graduate Studies and Research University of Alexandria national institute of Oceanography and Fisheries

Phosphorus(P) fractions and their bioavailability in the sediments from El Mex Bay and Lake Mariut in Egypt were investigated using different chemical extraction methods. Sodium bicarbonate(NaHC03)extractable P(Olsen-P) was the largest fraction(14.42%), followed by algal available P(AAP)(3.56%),water soluble P(WSP)(0.79%), and readily desorbable P(RDP)(0.06%) for El Mex Bay. While AAP contributed 9.94% to total P in sediments from Lake Mariut, Olsen-P 8.53%, WSP 4.11%, and RDP 0.92%.Summation of the bioavailable P fractions didn’t exceed the sediment quality guidelines, and, therefore, P doesn’t represent a danger to marine organisms. Correlation coefficients showed that no apparent relations between total P(TP) and iron(Fe), aluminum(Al), and calcium(Ca) in the sediments. Furthermore, Fe:P ratio was less than 15 indicting that there was not enough Fe in surface sediments to bind to P at most of the sampling sites. The positive correlation between TP and organic matter(OM) for Lake Mariut and El Mex Bay sediments indicated that the organic matter content of the sediment was a useful predictor of the total phosphorus content. Data from this study constitute a baseline of phosphorus bioavailability in sediments from El Mex Bay and Lake Mariut and could be used as a reference for future studies on the changes of bioavailable and residual phosphorus fractions over time.

关键词： Phosphorus bioavailability Sediments El Mex Bay Lake Mariut

Lidar Methods for Observing Mineral Dust

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Journal of Meteorological Research 2014年第2期28卷 173-184页

作者： Nobuo SUGIMOTO HUANG Zhongwei 黄忠伟 National Institute for Environmental Studies College of Atmospheric Sciences Lanzhou University

Lidar methods for observing mineral dust aerosols are reviewed.These methods include Mie scattering lidars,polarization lidars,Raman scattering lidars,high-spectral-resolution lidars,and fluorescence lidars.Some of the lidar systems developed by the authors and the results of the observations and applications are introduced.The largest advantage of the lidar methods is that they can observe vertical distribution of aerosols continuously with high temporal and spatial resolutions.Networks of ground-based lidars provide useful data for understanding the distribution and movement of mineral dust and other aerosols.The lidar network data are actually used for validation and assimilation of dust transport models,which can evaluate emission,transport,and deposition of mineral dust.The lidar methods are also useful for measuring the optical characteristics of aerosols that are essential to assess the radiative effects of aerosols.Evolution of the lidar data analysis methods for aerosol characterization is also reviewed.Observations from space and ground-based networks are two important approaches with the lidar methods in the studies of the effects of mineral dust and other aerosols on climate and the environment.Directions of the researches with lidar methods in the near future are discussed.

关键词： lidar mineral dust Mie scattering lidar Raman lidar high-spectral-resolution lidar fluorescence lidar

Can we go beyond INDCs： Analysis of a future mitigation possibility in China, Japan, EU and the U.S.

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Advances in Climate Change Research 2017年第2期8卷 117-122页

作者： JIANG Ke-Jun Kentaro TAMURA Tatsuya HANAOKA Energy Research institute (ERI) Beijing 100038 China institute for Global environmental Strategies (IGES) Hayama 240-0115 Japan National Institute for Environmental Studies (NIES) Tsukuba 305-8506 Japan

在巴黎协议的最重要的成就是由与形式 INDC 由每个国家 / 区域提交的承诺建立排放减小目标。然而，在 INDC 内的排放减小目标不能与排放小径匹配为对全球保留低于 2 这个世纪好的全球温度上升 ?

关键词：可能性分析联合国气候变化框架公约中国日本美国欧盟温度上升路径匹配

Investigation of HO_(2) uptake mechanisms onto multiple-component ambient aerosols collected in summer and winter time in Yokohama,Japan

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Journal of environmental Sciences 2024年第3期137卷 18-29页

作者： Jun Zhou Yukiko Fukusaki Kentaro Murano Tania Gautam Yu Bai Yoshimi Inomata Hiroaki Komatsu Mayuko Takeda Bin Yuan Min Shao Yosuke Sakamoto Yoshizumi Kajii institute for environmental and Climate Research Jinan UniversityGuangzhou 511443China Guangdong-Hongkong-Macao Joint Laboratory of Collaborative Innovation forenvironmental Quality Guangzhou 511443China Graduate School of Global environmental studies Kyoto UniversityKyoto606-8501Japan Yokohama environmental Science Research institute Yokohama Kanagawa 221–0024Japan Department of Chemistry University of AlbertaAlbertaEdmonton T6G 2G2Canada Graduate School of Human and environmental studies Kyoto UniversityKyoto 606-8501Japan Kanagawa environmental Research Center Kanagawa 254-0014Japan Center for Regional environmental Research National Institute for Environmental StudiesIbaraki305-8506Japan

The heterogeneous loss of HO_(2)radicals onto ambient aerosols plays an important role in tropospheric chemistry.However,sparse investigation of the dominating parameters controlling the HO_(2)uptake coefficients onto ambient aerosols(γHO_(2))has largely hindered the application of the measuredγHO_(2)to the global spatial prediction.Here we induced an offine method using LFP-LIF technique to measure the kinetics of HO_(2)uptake onto ambient aerosols collected in summertime and wintertime in Yokohama city,a regional urban site near Tokyo,Japan.By controlling the dominating parameters which infuenceγHO_(2),we were able to investigate the detailed HO_(2)uptake mechanism.We characterized the chemical composition of the collected ambient aerosols,including organics,inorganics,transition metals ions,etc.and modeledγHO_(2)using different mechanisms.Results show thatγHO_(2)increased with the increase in RH,and the aerosol states(“dry”or wet/aqueous)have large effects onγHO_(2).With fixed RH and aerosol chemical composition,γHO_(2)was highly dependent on pH and inversely correlated with[HO_(2)]_0.By combing the measuredγHO_(2)values with the modeled ones,we found that both the HO_(2)self-reaction and transition metal-catalyzed reactions should be accounted for to yield a single parameterization to predictγHO_(2),and different chemical compositions may have collective effects onγHO_(2).Results may serve for extending theγHO_(2)values measured at one observation site to different environmental conditions,which will help us to achieve more accurate modeling results concerning secondary pollutant formation(i.e.,ozone).

关键词： HO_(2)uptake kinetics Offine method Impacting factors Mechanism

Understanding surface water-groundwater conversion relationship and associated hydrogeochemistry evolution in the upper reaches of Luan River Basin， North China

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Journal of Earth Science 2022年

作者： Le Zhao Chunli Su Wenbo Liu Xianjun Xie School of environmental studies， China University of Geosciences China Geological environmental Monitoring institute

Luan River is the main water source in Beijing-Tianjin-Hebei region， northern China， where the groundwater system is vulnerable and pollution issue is serious. It is significance for protect regional groundwater resources to identify the hydrogeochemistry evolution and affecting factors along flow direction occurred in the upper reaches， especially the surface water-groundwater （SW-GW） conversion relationship. In this study， recharge， conversion and geochemistry evolution of SW and GW were elucidated based on physical-hydrochemical indicators and stable isotopes in 36 GW samples and 20 SW samples， which were collected in July 2019 and July 2020. The factor analysis was further utilized to determine the main factors responsible for regional hydrogeochemical evolution. Results indicated that GW recharged SW in plateau area， and SW and GW recharged each other in typical alpine valley area. The hydrochemical types are HCO;Ca·Mg and HCO;-Ca， and the hydrochemical evolution is dominated by weathering of silicate and carbonate minerals. The cation exchange adsorption has minor impact on groundwater hydrochemistry. The rise of SO;and NO;contents in groundwater are related to industrial and agricultural activities. The main controlling factors of SW hydrochemical components included recharge from groundwater， industrial and mining activities， explain 90.04% of data variance. However， water-rock interaction， agricultural and domestic sewage are responsible for GW quality， explain 83.38%.

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Long-term conservation tillage results in a more balanced soil microbiological activity and higher nutrient supply capacity

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International Soil and Water Conservation Research 2023年第3期11卷 528-537页

作者： Priyo Adi Nugroho Katalin Juhos Nandor Prettl Balazs Madarasz Zsolt Kotroczo Department of Agro-environmental studies Institute of Environmental ScienceHungarian University of Agriculture and Life SciencesHungary Geographical institute Research Centre for Astronomy and Earth SciencesBudapestHungary

Soil health depletion due to intensive tillage operations is a global issue in the agricultural sector.Conservation tillage(CT)which involves non-inversion tillage and leaving~30%of the soil surface covered with crop residues,is a strategy designed to enhance soil health.However,no comprehensive study to investigate the long-term effect of CT on soil biological activity and the soil nutrient supply has yet been widely carried out.Biological and chemical soil properties were assessed at depths 0-5,10-15,and 20-25 cm depths after 18 years of CT and conventional tillage practice(PT).Various stages in the vegetative growth of maize were investigated in 2021 in Hungary.The findings indicated that tillage intensity,soil depth,and growth stages all significantly influenced soil enzyme activities and the concentration of soil nutrients.Less soil disturbance resulted in a significantly larger concentration of soil carbon parameters(total organic carbon and labile carbon)in CT plots,where the activity ofβ-glucosidase and dehydrogenase(DHA)in the upper soil layer increased significantly(0.7-2.6 and 2.6-4.7 times,respectively)compared to PT.The high amount of organic matter and the greater resistance to erosion observed in CT also contributed to the higher concentration of available nutrients(NH_(4),NO_(3),Ca,K)and total P in the surface soil layer.Phosphatase activity was highest in the mid-stage of vegetative growth and was positively correlated to the total P concentration.The alterations in soil water content were clearly negatively corelated with the change in DHA and phosphatase activity.Overall,due to the more balanced environmental conditions,the decomposition of organic substances was more balanced and slower in CT than in PT.This implied that the mobilization of nutrients in the soil was more balanced as well,and that the nutrients were released gradually.The enhancement of the soil nutrient-supplying capacity achieved by means of long-term conservation tillage provides a promising strategy for sustainable nutrient

关键词： Dehydrogenase β-glucosidase Phosphatase Nutrient balance Mineralization

environmental Mn(Ⅱ) enhances the activity of dissimilatory arsenate-respiring prokaryotes from arsenic-contaminated soils

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Journal of environmental Sciences 2023年第3期125卷 582-592页

作者： Yan Wu Weiwei Wu Yifan Xu Yanxia Zuo Xian-Chun Zeng State Key Laboratory of Biogeology and environmental Geology&School of environmental studies China University of Geosciences(Wuhan)Wuhan 430074China institute of Hydrobiology the Chinese Academy of SciencesWuhan 430072China

Many investigations suggest that dissimilatory arsenate-respiring prokaryotes (DARPs) play a key role in stimulating reductive mobilization of As from solid phase into groundwater,but it is not clear how environmental Mn(Ⅱ) affects the DARPs-mediated reductive mobilization of arsenic.To resolve this issue,we collected soil samples from a realgar tailingsaffected area.We found that there were diverse arsenate-respiratory reductase (arr) genes in the soils.The microbial communities had high arsenate-respiring activity,and were able to efficiently stimulate the reductive mobilization of As.Compared to the microcosms without Mn(Ⅱ),addition of 10 mmol/L Mn(Ⅱ) to the microcosms led to 23.99%-251.79% increases in the microbial mobilization of As,and led to 133.3%-239.2% increases in the abundances of arr genes.We further isolated a new cultivable DARP,Bacillus sp.F11,from the arseniccontaminated soils.It completely reduced 1 mmol/L As(V) in 5 days under the optimal reaction conditions.We further found that it was able to efficiently catalyze the reductive mobilization and release of As from the solid phase;the addition of 2 mmol/L Mn(Ⅱ) led to 98.49%-248.78% increases in the F11 cells-mediated reductive mobilization of As,and70.6%-104.4% increases in the arr gene abundances.These data suggest that environmental Mn(Ⅱ) markedly increased the DARPs-mediated reductive mobilization of As in arseniccontaminated soils.This work provided a new insight into the close association between the biogeochemical cycles of arsenic and manganese.

关键词： dissimilatory arsenate-respiring prokaryote Arsenic mobilization Arsenic-contaminated groundwater Arsenate reduction Mn(II)

Reflections on Paradigm Shift in Urban System Reconstruction

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Chinese Journal of Urban and environmental studies 2019年第2期07卷 76-91页

作者： PAN Jiahua institute for Urban and environmental studies Chinese Academy of Social Sciences

In the era of agricultural civilization, the city size and layout adapted to nature and natural productivity; while in the era of industrial civilization, the constraints of natural productivity were broken by technological means, and the increasing returns to scale have enabled the urban population size to exceed 10 million and the urban population density to exceed 10,000people/km;. Under the paradigm of industrial civilization, the spatial agglomeration of resources is driven by economic rationality. Besides, China’s urban hierarchy has become a barrier and further strengthened the polarization trend of city size, resulting in an urban system in which the cities at higher administrative levels concentrate a lot of resources while suffering from prominent urban diseases, small-and medium-sized cities lack development vitality, and urban and rural areas are separated from each other. The historical experience that the flow of resource factors between urban and rural areas facilitates a relatively balanced spatial distribution of quality resources is worth learning. Under the paradigm of ecological civilization, it is important to harmonize humans with nature in the transformation and reconstruction by pursuing nature-based solutions, and build a low-carbon, resilient, and coordinated urban system.

关键词： Urban system urban–rural synergies free flow of factors transformation and reconstruction

Temperature evolution from the δ ^(18)O record of Hani peat, Northeast China, in the last 14000 years

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Science China Earth Sciences 2009年第5期52卷 952-964页

作者： Shibata YASUYUKI environmental Chemistry Division National Institute for Environmental Studies Tsukuba

From the last deglaciation to the Holocene, the Greenland Ice Core (GISP2) δ 18O records as well as the records of ice-rafted debris on the surface of the North Atlantic have revealed a succession of sudden cooling events on the centennial to millennial scales. However, the temperature proxy records are rarely studied systematically and directly to ensure that this air temperature cooling pattern simultaneously existed in the East Asian Region, in addition to the repeated pattern occurring in the Greater Atlantic Region. A peat cellulose δ 18O temperature proxy record proximately existing for 14000 years was picked up from the Hani peat in Jilin Province, China. It suggests by comparison that the sudden cooling events, such as the Older Dryas, Inter-Allerφd, Younger Dryas, and nine ice-rafted debris events of the North Atlantic, are almost entirely reiterated in the temperature signals of Hani peat cellulose δ 18O. These cooling events show that the repeatedly occurring temperature cooling pattern not only appeared in the North Atlantic Region in the high latitudes, but also in the Northwest Pacific Region in the middle latitudes. The climate change events marking the start of the Holocene Epoch, the Holocene Megathermal, the "8.2 kyr" event, the "4.2 kyr" event, the Medieval Warm Period, and the Little Ice Age are further discussed. The sensitivity response of Hani peat cellulose δ 18O to the land surface temperature and the reason for the age accuracy of peat cellulose 14C are also discussed based on the characteristics of the peat bog environment.

关键词： Holocene abrupt climate change peat Holocene Megathermal 8.2 kyr event 4.2 kyr event Medieval Warm Period Little Ice Age

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