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Meteorological and environmental Research 2022年第6期13卷 31-34,41页

作者： Xianshuang YANG ecological environment monitoring station of Beibei District Chongqing 400700China

Based on a mobile monitoring system,101 volatile organic compounds(VOCs)in ambient air near a national control station in an industrial park were monitored during February 15-21 in 2022,and the pollution characteristics and ozone formation potential(OFP)of VOCs were *** results show that among the top 10 VOCs with higher mass concentration,there were 5 VOCs appearing in each day from February 15 to 21,including styrene,benzene,toluene,undecane and n-decane,which indicates that the sources of VOCs emission at the monitoring point were relatively *** the monitoring period,aromatic hydrocarbons contributed the most to the ozone formation potential of VOCs,accounting for above 70%,followed by alkanes and oxygen-containing *** total OFP of aromatic hydrocarbons,alkanes and oxygen-containing compounds accounted for more than 90%,so they became the active components with the greatest influence on ozone *** hydrocarbons such as 1,2,4-trimethylbenzene,1,3,5-trimethylbenzene and m/p-dimethylbenzene,oxygen-containing organic compounds such as ethanol and acetone,and alkanes such as n-nonane and butane had high OFP,so they had a great effect on ozone formation.

关键词： VOCs Pollution characteristics OFP

Research on the discrimination methods of algae based on the fluorescence excitation spectra

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Acta Oceanologica Sinica 2010年第4期29卷 116-128页

作者： HU Xupeng SU Rongguo ZOU Weiming REN Shijun WANG Hongtao CHAI Xiaoping WANG Yiming Zhejiang Provincial Zhoushan Marine ecological environmental monitoring station Zhoushan 316000 China College of Chemistry and Chemical Engineering Ocean University of China Qingdao 266100 China

The excitation spectra of chlorophyll （Chl） fluorescence can be used to differentiate phytoplankton populations at phylum level in vivo and in situ within a few *** investigated phytoplankton divisions （Dinophyta,Bacillariophyta,Chrysophyta,Cyanophyta,Cryptophyta,Chlorophyta） are each characterized by a specific composition of photosynthetic antenna pigments and,consequently,by a specific excitation spectrum of the Chl *** excitation spectra （emission of 680 nm and excitation of 400–600 nm） of every division were obtained from several species per division by a F4500 fluorescence ***’s linear discriminant analysis of the norm spectra shows that the divisions could be *** discrimination method,established by multivariate linear regression and weighted least squares,was used to differentiate the phytoplankton samples cultured in the laboratory and samples collected from the Jiaozhao Bay at division *** correctly discriminated samples were more than 94% for single algal species ones,more than 84% for simulatively mixed ones,more than 83% for real mixed ones and 100% for samples collected from the Jiaozhou Bay for the dominant *** method for phytoplankton differentiation described here can be applied to routine checking by fluorescence spectrophotometer,and benefit the monitoring and supervision tasks related to phytoplankton populations in the marine environments.

关键词： fluorescence spectrum discrimination weighted least squares phytoplankton

Unveiling evapotranspiration patterns and energy balance in a subalpine forest of the Qinghai-Tibet Plateau:observations and analysis from an eddy covariance system

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Journal of Forestry Research 2024年第3期35卷 175-188页

作者： Niu Zhu Jinniu Wang Dongliang Luo Xufeng Wang Cheng Shen Ning Wu Ning Zhang Binghui Tian Aihong Gai Chengdu Institute of Biology Chinese Academy of SciencesChengdu 610041People's Republic of China College of Resources and environmental Sciences Gansu Agricultural UniversityLanzhou 730070People's Republic of China Mangkang ecological monitoring station Tibet Ecological Security Barrier Ecological Monitoring NetworkQamdo 854500People's Republic of China Northwest Institute of Eco environmental Resources Chinese Academy of SciencesLanzhou 730000People's Republic of China

Evapotranspiration is an important parameter used to characterize the water cycle of *** under-stand the properties of the evapotranspiration and energy balance of a subalpine forest in the southeastern Qinghai-Tibet Plateau,an open-path eddy covariance system was set up to monitor the forest from November 2020 to October 2021 in a core area of the Three Parallel Rivers in the Qing-hai-Tibet *** results show that the evapotranspira-tion peaked daily,the maximum occurring between 11:00 and 15:*** factors had significant effects on evapotranspiration,among them,net radiation the greatest(R^(2)=0.487),and relative humidity the least(R^(2)=0.001).The energy flux varied considerably in different seasons and sensible heat flux accounted for the main part of turbulent *** energy balance ratio in the dormant season was less than that in the growing season,and there is an energy imbalance at the site on an annual time scale.

关键词： Evapotranspiration Energy balance Subalpine forest Three Parallel Rivers region Southeast Qinghai-Tibet Plateau

Research,Extension,and Good Farming Practices Improve Water Quality and Productivity

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Journal of Integrative Agriculture 2012年第1期11卷 14-30页

作者： Clinton C Shock Candace B Shock Oregon State University Malheur Experiment station Scientific ecological Services

Agriculture in southeastern Oregon and southwestern Idaho known collectively as the Treasure Valley has depended on furrow irrigation using heavy inputs of water and nitrogen （N） fertilizer. Crop rotations include onion, corn, wheat, sugar beet, potato, bean, and other crops. By 1986 groundwater had become contaminated with nitrate and residues of the herbicide chlorthal-dimethyl （DCPA）; an official groundwater management area was established by the Oregon Department of environmental Quality along with an action plan and well monitoring network. The action plan allowed for a trial period to see whether voluntary changes would improve trends. Researchers, producers, and agencies cooperated to develop production options that had the possibility of being both environmentally protective and cost effective. Options were tested to improve irrigation practices, increase N fertilizer use efficiency on several rotation crops, and find a cost effective replacement for DCPA. Research demonstrated the opportunity for increased productivity through both irrigation scheduling and the adoption of drip and sprinkler systems. Fertilizer research demonstrated that smaller, more frequent N applications were more efficient than a single large application. Effective, lower cost herbicides replaced DCPA. Research results were effectively delivered through many means and voluntarily adopted. Both groundwater nitrate and DCPA residues are declining. Productivity has increased.

关键词： DCPA drip irrigation groundwater nitrate irrigation management irrigation scheduling nutrient management voluntary cooperation

Terrestrial input and nutrient change reflected by sediment records of the Changjiang River Estuary in recent 80 years

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Acta Oceanologica Sinica 2015年第2期34卷 27-35页

作者： LI Junlong ZHENG Binghui HU Xupeng WANG Yiming DING Ye LIU Fang College of Water Sciences Beijing Normal University State Key Laboratory of environmental Criteria and Risk Assessment Chinese Research Academy of Environmental Sciences State environmental Protection Key Laboratory of Quality Control in environmental monitoring China National Environmental Monitoring Center Zhoushan Marine ecological environmental monitoring station

A variety of environmental problems have been observed in the Changjiang River Estuary and adjacent coastal area, including eutrophication, harmful algal blooms（HABs）, and hypoxia in recent decades. Application of sedimentary biogenic element indicators on the study of paleoenvironment can reconstruct environmental evolution history of waters. Two 210Pb-dated cores were collected from the Changjiang River Estuary（S3） and adjacent coastal area（Z13）, and total organic carbon（TOC）, total nitrogen（TN）, biogenic silicon（BSi）, total phosphorus（TP） and phosphorus（P） species were analyzed. Three stages of environmental changes are deduced by the nutrient sedimentary records. First, nutrient concentration increased rapidly since the 1950 s, which attributed to agriculture development and overused chemical fertilizers. Second, nutrient concentration kept high and primary production began to promote during the 1960 s to 1980 s, while diatom abundance and proportion began to decline since the 1970 s, accompanied by reduced 23 Si O- concentration and flux from the river. Third, due to several dams and bridges constructed, river runoff and coastal hydrodynamic conditions reduced to a certain extent since the 1990 s, which aggravated the unbalance in nutrient structure. Multi-nutrient proxies in sediment can reflect the natural environm-ental changes as well as influence of human activities.

关键词： biogenic elements phosphorus species sediment cores Changjiang River Estuary

Quantitative contributions of climate change and human activities to vegetation dynamics in the Zoige Plateau from 2001 to 2020

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Journal of Mountain Science 2024年第9期21卷 3031-3046页

作者： GAO Bing LIU Enqin YANG Yang YANG Man YAO Yang GUAN Lei FENG Yiwen College of Geography and Planning Chengdu University of TechnologyChengdu 610059China Key Laboratory of Smart Earth Beijing 100029China Sichuan Provincial Soil and Water Conservation ecological environment monitoring station Chengdu 610041China College of Earth and Planetary Sciences Chengdu University of TechnologyChengdu 610059China

Climate change and human activities such as overgrazing and rapid development of tourism simultaneously affected the vegetation of the Zoige ***,the spatiotemporal variations of vegetation and the relative contributions of climate change and human activities to these vegetation dynamics remain ***,clarifying how and why the vegetation on the Zoige Plateau changed can provide a scientific basis for the sustainable development of the ***,we investigate NDVI trends using the Normalized Difference Vegetation Index(NDVI)as an indicator of vegetation greenness and distinguish the relative effects of climate changes and human activities on vegetation changes by utilizing residual trend analysis and the *** find a tendency of vegetation greening from 2001 to 2020,with significant greening accounting for 21.44%of the entire ***,browning area expanded rapidly after *** temperatures are the primary driver of vegetation changes in the Zoige *** variations and human activities were responsible for 65.57%and 34.43%of vegetation greening,and 39.14%and 60.86%of vegetation browning,respectively,with browning concentrated along the Yellow,Black and White *** to 2001-2010,the inhibitory effect of human activity and climate fluctuations on vegetation grew dramatically between 2011 and 2020.

关键词： Vegetation change Climate change Residual trend analysis Geodetector Human activities Zoige plateau

Vegetation Traits and Soil Properties in Response to Utilization Patterns of Grassland in Hulun Buir City, Inner Mongolia, China

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Chinese Geographical Science 2014年第4期24卷 471-478页

作者： LIU Miao LIU Guohua WU Xing WANG Hao CHEN Li State Key Laboratory of Urban and Regional Ecology Research Center for Eco-Environmental SciencesChinese Academy of Sciences University of Chinese Academy of Sciences monitoring station for Eco-environment of Hulun Buir

Numerous studies have focused on vegetation traits and soil properties in grassland, few of which concerned about effects of human utilization patterns on grassland yet. Thus, this study hypothesized that human disturbance(e.g., grazing, mowing and fencing) triggered significant variation of biomass partitioning and carbon reallocation. Besides, there existed some differences of species diversity and soil fertility. To address these hypotheses of grassland with diverse utilization patterns in Hulun Buir City, Inner Mongolia, China, we sampled in situ about aboveground biomass(AGB) and belowground biomass(BGB) to evaluate their biomass allocation. Species diversity and soil properties were also investigated. Subsequently, we discussed the relationship of species diversity with environmental conditions, using data collected from 23 sites during the ecological project period of Returning Grazing Lands to Grasslands(RGLG) program. The results were as follows: 1) both AGB and BGB were lower on grazing regime than those on fencing and mowing, but the ratio of root-to-shoot(R/S) was higher on grazing regime than the other two utilization patterns; 2) neither of evenness and Simpson Index was different significantly among all grassland utilization patterns in desert, typical, and meadow grassland at 0.05. In meadow grassland, species richness of fencing pattern was significantly higher than that of grazing pattern(p < 0.05); 3) both of soil organic carbon content and soil available phosphorous content were increased significantly on fencing pattern than grazing pattern(p < 0.05) in desert grassland, and mowing patterns increased the soil nutrients(soil organic carbon, soil total phosphorous, soil available phosphorous, and soil total nitrogen) significantly compared with grazing patterns(p < 0.05) in typical grassland. However, there were no significant differences among utilization patterns in meadow grassland. In conclusion, both of AGB and BGB were increased significantl

关键词： grassland utilization pattems biomass allocation species diversity soil properties temperate grassland Hulun Buir City

Identifying human-induced influence on microbial community:A comparative study in the effluent-receiving areas in Hangzhou Bay

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Frontiers of environmental Science & Engineering 2019年第6期13卷 103-113页

作者： Yuhan Zheng Zhiguo Su Tianjiao Dai Feifei Li Bei Huang Qinglin Mu Chuanping Feng Donghui Wen School of Water Resource and environmental Science China University of Geosciences(Beijing)Beijing 100083China College of environmental Sciences and Engineering Peking UniversityBeijing 100871China Zhejiang Provincial Zhoushan Marine ecological environmental monitoring station Zhoushan 316021China

Microbial community structure is afiected by both natural processes and human *** coastal area,anthropegenetic activity can usually lead to the discharge of the effluent from wastewater treatment plant(WWTP)to sea,and thus the water quality chronically turns worse and marine ecosystem becomes *** play key roles in pollutants degradation and ecological restoration;however,there are few studies about how the WWTP effluent disposal influences coastal microbial *** this study,sediment samples were collected from two WWTP effluentreceiving areas(abbreviated as JX and SY)in Hangzhou ***,based on the high-throughput sequencing of 16S rRNA gene,microbial community structure was ***,several statistical analyses were conducted to reveal the microbial community characteristics in response to the effluent *** PCoA,the significant difference of in microbial community structure was determined between JX and SY;using RDA,water COD and temperature,and sediment available phosphate and ammonia nitrogen were identified as the key environmental factors for the community difference;using LDA effect size analysis,the most distinctive microbes were found and their correlations with environmental factors were investigated;and according to detrended beta-nearesttaxon-index,the sediment microbial communities were found to follow"niche theory".An interesting and important finding was that in SY that received more and toxic COD,many distinctive microbes were related to the groups that were capable of degrading toxic organic *** study provides a clear illustration of eco-environmental deterioration under the long-term human pressure from the view of microbial ecology.

关键词： Microbial community structure Effluent-receiving area High-throughput sequencing Costal sediments Wastewater treatment plant(WWTP)

Composition and size distribution of wintertime inorganic aerosols at ground and alpine regions of northwest China

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Chinese Chemical Letters 2024年第11期35卷 238-242页

作者： Haijiao Liu Qiao Feng Yu Huang Feng Wu Yali Liu Minxia Shen Xiao Guo Wenting Dai Weining Qi Yifan Zhang Lu Li Qiyuan Wang Bianhong Zhou Jianjun Li State Key Laboratory of Loess and Quaternary Geology Key Lab of Aerosol Chemistry and PhysicsInstitute of Earth EnvironmentChinese Academy of SciencesXi'an 710061China Xi'an Institute for Innovative Earth environment Research Xi'an 710061China College of Geography and environment Baoji University of Arts and SciencesShaanxi Key Laboratory of Disaster Monitoring and Mechanism SimulationBaoji 721013China National Observation and Research station of Regional ecological environment Change and Comprehensive Management in the Guanzhong Plain ShaanxiXi'an 710061China

Water-soluble inorganic ions(WSIIs)play a pivotal role in atmospheric chemical reactions,particularly influencing the formation of secondary particulate matter.A comprehensive grasp of the vertical distribution of atmospheric pollutants holds immense significance in understanding the diffusion and transportation of these *** study investigates the WSIIs of PM_(2.5)and size-segregated particles at the top(~2060 m a.s.l.)and foot of *** during the winter of *** the measured ions present significant higher concentrations(1.9~6.9 times)at the foot than the ***^(-)and K^(+)at the foot are more than 4 times of those at the top,whereas Ca^(2+)and Mg^(2+)are only 1.3-1.9 times *** particle size distribution of NO_(3)^(-),SO_(4)^(2-),K^(+)and Cl^(-)demonstrate a single peak distribution(0.7-1.1μm)at the foot,but with a bimodal distribution(0.7-1.1μm and 4.7-5.8μm)at the *** differences suggest that the aerosol at the alpine region is mainly transported via long-distance from Northwest/North China,but limited influenced by vertical transport through valley *** changes of concentration and size distribution of WSIIs in dust event and non-dust period indicate that the effects of dust event on aerosols at ground surface were weaker than that of the free troposphere of Guanzhong ***,our study underscores the dominant influence of NO_(3)^(-)in shaping the gas-particle distribution of ammonia within the winter free *** results highlight the significant role of long-range transport on aerosols in the free troposphere in Guanzhong Plain,Northwest China.

关键词： Water-soluble inorganic ions Size distribution Aerosol acidity Ammonia Free troposphere

One century record of contamination by polycyclic aromatic hydrocarbons and polychlorinated biphenyls in core sediments from the southern Yellow Sea

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Journal of environmental Sciences 2009年第8期21卷 1080-1088页

作者： ZHANG Peng SONG Jinming FANG Jie LIU Zhigang LI Xuegang YUAN Huamao Key Laboratory Marine Ecology and environmental Sciences Institute of Oceanology Chinese Academy of Scienees Qingdao 266071 China The Graduate University of Chinese Academy of Sciences Beijing 100039 China Zhejiang Zhoushan Marine ecological environmental monitoring station Zhoushan 316004 China

Sixteen polycyclic aromatic hydrocarbons （PAHs） and 28 polychlorinated biphenyls （PCBs） were measured at a 2-cm interval in a core sample from the middle of the southern Yellow Sea for elucidating their historical variations in inflow and sources. The chronology was obtained using the ^210Pb method. PAHs concentrations decreased generally with depth and two climax values occurred in 14-16 cm and 20-22 cm layers, demonstrating that the production and usage of PAHs might reach peaks in the periods of 1956-1962 and 1938-1944. The booming economy and the navy battles of the Second World War might explain why the higher levels were detected in the two layers. The result of principal component analysis （PCA） revealed that PAHs were primarily owing to the combustion product. Down-cored variation of PCB concentrations was complex. Higher concentrations besides the two peaks being the same as PAHs were detected from 4 to 8 cm, depositing from 1980 to 1992, which probably resulted from the disposal of the out-dated PCB-containing equipment. The average Cl percentage of PCBs detected was similar to that of the mixture of Aroclor 1254 and 1242, suggesting they might origin from the dielectrical and heat-transfer fluid. The total organic carbon （TOC） content played a prevalent role in the adsorption of high molecular weight PAHs （≥ring）, while no obvious relationship among total PCBs, the concentration of congeners, and TOC was found.

关键词： PAHs PCBs the southern Yellow Sea contamination history