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Chinese Geographical Science 2020年第1期30卷 180-188页

作者： WANG Liwei ZHANG Mingjun WANG Shengjie Athanassios AARGIRIOU WANG Gaofei Vasileios SALAMALIKIS SHI Mengyu JIAO Rong College of Geography and Environmental Science Northwest Normal UniversityLanzhou 730070China Institute of Desert Meteorology China Meteorological AdministrationUrumqi 830002China State Key Laboratory of Cryospheric Sciences Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China Laboratory of Atmospheric Physics Physics DepartmentUniversity of PatrasPatras G&26500Greece Meteorological Bureau of Jeminay County Xinjiang Altay 836500China

stable oxygen isotopes in precipitation contain meaningful environmental information on a synoptic scale and can be applied to diagnose hydrometeorological processes.A series of rainstorms occurred at the southern Tianshan Mountains during the period from May to June 2013,and the event-based precipitation was sampled along the mountain range from west to *** on δ18 O values in precipitation samples as well as the corresponding meteorological parameters,the moisture transport paths during the sampling period were *** late-May(stage 1),isotopes in precipitation collected generally showed a depleting *** mid-June(stage 2),there was no coherent trend of isotopes in precipitation for these stations,and only isotope values in Aksu showed a continually depleting *** other meteorological proxies during the sampling period,the event-based precipitation isotopes sensitively reflected the moisture *** central Asia,both the westerly and monsoon moisture can be delivered to cause extreme precipitation events,and the isotopic information provides an alternative tool to investigate the atmospheric processes.

关键词： precipitation stable isotope moisture source Tianshan Mountains

Application of enriched stable isotope technique to the study of copper bioavailability in Daphnia magna

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Journal of Environmental Sciences 2011年第5期23卷 831-836页

作者： Wenhong Fan Chenguang WU Chunmei Zhao Tao Yu Yuan Zhang Department of Environmental Science and Engineering School of Chemistry and Environment Beihang University Beijing 100191 China. E-mail: fanwh @ buaa. edu. cn Chinese Research Academy of Environmental Sciences Beijing 100012 China

The biokinetics of Cu in Daphnia magna, including dissolved uptake, assimilation and efflux, has been determined using a gamma 67^Cu radiotracer methodology. However, this gamma emitting radioisotope is not readily available due to its very short half-life. In the present study, we employed a stable isotope tracer （65^Cu） to determine the Cu biokinetics and compared our results to those determined using 67^Cu. The dissolved uptake rate constant of 65^Cu was 3.36 L/（***）, which is higher than that of 67^Cu （1.32 L/（***））. With increasing food concentrations from 2×10^4 to 1×10^5 cells/mL, the Cu assimilation efficiency （AE） decreased from 46% to 11%, compared to a decrease from 27% to 16% when determined using 67^Cu. The effiux of Cu from Daphnia magna was quantified following both dissolved and dietary uptake. The efflux of waterborne Cu was comparable to that of dietborne Cu and the effiux rate constant （0.32-0.52 day^-l） was higher than that determined by 67^Cu （0.19-0.20 day^-1）. By considering different water properties and handling procedure between the two experiments, we believe that these differences are reasonable. Overall, this study demonstrated that the enriched stable isotope tracer technique is a powerful tool to investigate metal bioavailability and maybe a good alternative to radioactive measurements.

关键词： stable isotope Daphnia magna copper bioavailability

Cleaning of Marine Sediment Samples for Large Diatom stable isotope Analysis

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Journal of Earth Science 2012年第2期23卷 161-172页

作者：熊志方李铁刚 Xavier Crosta Key Laboratory of Marine Geology and Environment Institute of OceanologyChinese Academy of Sciences UMR-CNRS 5805 EPOC UniversitéBordeaux 1Avenue des Facultés

Diatom stable isotope analysis offers considerable potential in palaeoceanography, par-ticularly where carbonate material is scarce or absent. However, extracting pure diatom frustules free of external labile organic matter from marine sediments is an essential requirement for their applica-tions as paleoenvironmental proxies. Here, based largely on previous work, we developed a method in-cluding physical separation and chemical oxidation steps to concentrate and clean pure large diatoms from laminated diatom mat and diatomaceous clay sediment samples for their stable isotope analysis. Using the physical separation techniques consisting of the removal of carbonate and excess organic matter, sieving, differential settling, and heavy liquid floatation, pure diatoms can be successfully iso-lated from the sediment samples with opal concentration more than 10%. Subsequent time oxidation experiment shows that labile organic matter coating pure diatom valves can be effectively removed with 30% H2O2 at 65 ℃ for 2 h. Measurements of δ13C after every step of physical separation demonstrate that contaminants and lost diatoms can influence the original diatom stable isotope signal, highlighting the importance of a visual check for dominant diatom size in the initial sample and purity in the final sample. Although the protocol described here was only applied to diatom mats or diatom oozes con-taining large diatoms （Ethmodiscus rex）, we believe that this method can be adapted to common dia-toms of general marine sediment samples.

关键词： large diatom stable isotope physical separation chemical oxidation Parece Vela basin palaeoceanography.

Spatial variations in food web structures with alternative stable states:evidence from stable isotope analysis in a large eutrophic lake

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Journal of Oceanology and Limnology 2018年第2期36卷 385-394页

作者： LI Yunkai ZHANG Yuying XU Juan ZHANG Shuo College of Marine Sciences Shanghai Ocean University Shanghai 201306 China Marine Sciences Program School of Environment Arts and Society Florida International University 3000 NE 151st St. North Miami Florida 33181 USA Donghu Experimental Station of Lake Ecosystems State Key Laboratory of Freshwater Ecology and Biotechnology of China Institute of Hydrobiology Chinese Academy of Sciences Wuhan 430072 China

Food web structures are well known to vary widely among ecosystems. Moreover, many food web studies of lakes have generally attempted to characterize the overall food web structure and have largely ignored internal spatial and environmental variations. In this study, we hypothesize that there is a high degree of spatial heterogeneity within an ecosystem and such heterogeneity may lead to strong variations in environmental conditions and resource availability, in turn resulting in dif ferent trophic pathways. stable carbon and nitrogen isotopes were employed for the whole food web to describe the structure of the food web in different sub-basins within Taihu Lake. This lake is a large eutrophic freshwater lake that has been intensively managed and highly influenced by human activities for more than 50 years. The results show significant isotopic dif ferences between basins with dif ferent environmental characteristics. Such differences likely result from isotopic baseline dif ferences combining with a shift in food web structure. Both are related to local spatial heterogeneity in nutrient loading in waters. Such variation should be explicitly considered in future food web studies and ecosystem-based management in this lake ecosystem.

关键词： stable isotope food web structure spatial heterogeneity Taihu Lake community

Spatial differentiation in stable isotope compositions of surface waters and its environmental significance in the Issyk-Kul Lake region of Central Asia

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Journal of Mountain Science 2018年第2期15卷 254-263页

作者： MA Long JILILI Abuduwaili LI Yao-ming State Key Laboratory of Desert and Oasis Ecology Xinjiang Institute of Ecology and Geography Chinese Academy of Sciences Urumqi 830011 China CAS Research Center for Ecology and Environment of Central Asia Urumqi 830011 China

stable isotope values of oxygen （180） and hydrogen （2H） of surface waters were used to study the origin and environmental significanees in the Issyk-Kul basin of Kyrgyzstan in Central Asia, which is the most important intermountain basin in the modern Tien Shan orogen. This study is the first analysis of hydrochemical spatial differentiation in the stable isotopes of surface waters in this watershed. 75 samples were collected from rivers, springs, lakes, rain and snow during the rainy season in July and August of 2o16. stable isotopes of 180 and 2H were studied for all samples, and cation ratios （Sr/Ca and Mg/Ca） were also determined for lake water samples. stable isotope values from precipitation scattered around the Local Meteoric Water Line （determined from Urumqi Station of the global network of isotopes in precipitation （GNIP））, together with values of the Deuterium excess parameter （d） from 15.3‰ to 30.5‰, with an average of 19.8‰, indicating that the moisture sources are primarily from regions with low relative humidity. The 8180 and 52H values were significantly different between the river and lake samples, indicating that regional evaporation caused the isotopic enrichment of lake water. Geospatial autocorrelation, measured by Moran＇s I coefficient, indicated weak spatial autocorrelation within stable isotopes of oxygen and hydrogen in the surface waters of the studied area, which is primarily an effect of climate during the water chemistry evolution. The cation ratios Sr/Ca and Mg/Ca in lake water samples were not correlated with the concentration of total dissolved solids, but did show correlation with stable isotopic values, which is significant for paleoenvironmental reconstruction.

关键词： Spatial differentiation stable isotope Moisture Sources Geospatial autocorrelation IssykKul Lake Central Asia

Food sources of the Manila clam Ruditapes philippinarum in intertidal areas:evidence from stable isotope analysis

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Chinese Journal of Oceanology and Limnology 2013年第4期31卷 782-788页

作者：赵力强闫喜武杨凤 College of Fisheries and Life Science Dalian Ocean University

Based on stable isotope analysis, we characterized the dietary regime of the Manila clam Ruditapesphilippinarum inhabiting intertidal areas along the Liaodong Peninsula, Northern China. Samples, including particulate organic matter （POM; n=30）, benthic microalgae （BMI; n=30） and R. philippinarum （n=60）, were collected from six sampling sites displaying the same ecological conditions. Of the two primary food sources, POM was more depleted in δ13C （-20.61‰ to -22.89%0） than BMI was （-13.90‰ to -16.66‰）. With respect to 15N, BMI was more enriched （2.90%0 to 4.07%0） than POM was （4.13‰ to 5.12‰）. The δ13C values of R. philippinarum ranged from -18.78‰ to -19.35‰ and the δ15N values from 7.96%0 to 8.63‰, which were intermediate between the POM and BMI values. In a two-source isotope mixing model, we estimated the relative contributions of POM and BMI to the diet ofR. philippinarum to be 74.2% and 25.8%, respectively. We conclude that R. philippinarum feeds mainly on POM, and BMI is also an important supplemental food source in intertidal areas.

关键词： Ruditapesphilippinarum food source stable isotope intertidal areas

Dietary preferences and potential ecological impact on the zooplankton community of Nemopilema nomurai based on stable isotope and fatty acid analyses

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Journal of Oceanology and Limnology 2022年第3期40卷 1085-1096页

作者： Junjian WANG Chaolun LI Guang YANG Zhencheng TAO Yanqing WANG Haochen XIAN Key Laboratory of Marine Ecology and Environmental Sciences Institute of OceanologyChinese Academy of SciencesQingdao 266071China Laboratory for Marine Ecology and Environmental Science Pilot National Laboratory for Marine Science and Technology(Qingdao)Qingdao 266237China North China Sea Marine Forecasting Center of State Oceanic Administration Qingdao 266100China Center for Ocean Mega-Science Chinese Academy of SciencesQingdao 266071China University of Chinese Academy of Sciences Beijing 100049China Department of Engineering and Technology Institute of Oceanology Chinese Academy of SciencesQingdao 266071China

Information on the dietary composition and food preferences of the giant jellyfish Nemopilema nomurai is important for understanding the trophic drivers of jellyfish outbreaks and their ecological *** used fatty acid(FA)and stable isotope(SI)biomarkers to analyze the diet of *** from the Yellow Sea in August *** was found at all sampling stations,with abundances ranging from 59 inds./km^(2) to 1651 inds./km^(2).There were no significant differences between large(>80 cm in diameter)and small(20–30 cm in diameter)medusae,either in FA compositions or in SI values,which suggests that large and small jellyfi sh have the same food composition and similar trophic *** to other zooplanktons,the relatively high levels of C20꞉4n-6 in total FAs(~12%)indicates that organic detritus contributes considerably to the food composition of the *** mixed model stable isotope Analysis in R(SIAR)revealed that *** tended to prey on smaller organisms(<1000μm in diameter)which comprised about 70%of its *** means the *** blooms will put high feeding pressure on the small *** similar SI values and FA composition indicates that krill may share the same food resources with ***,which suggests that the jellyfi sh blooms may affect krill populations as a result of food competition.

关键词： Nemopilema nomurai fatty acid stable isotope dietary preferences

Composition of stable isotope in precipitation and its influences by different vapor sources in the eastern Qilian Mountains

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Journal of Mountain Science 2018年第10期15卷 2207-2217页

作者： JIA Wen-xiong MA Xing-gang XU Xiu-ting YUAN Rui-feng DING Dan ZHU Guo-feng College of Geography and Environmental Science Northwest Normal UniversityLanzhou 730070China State Key Laboratory of Cryosphere Sciences Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 73ooooChina

To better understand the process of precipitation and water cycle, the composition of stable isotope in precipitation and its influences by different vapor sources in the eastern of Qilian Mountains were conducted from June 2013 to May 2014. The total of 100 precipitation samples were collected in Wushaoling national meteorological station located in the eastern of Qilian Mountains. The analysis indicates that the slope of Local Meteoric Water Line is lower than that of Global Meteoric Water Line. The average values of δ18 O and δD in precipitation are higher in summer but lower in winter. Except for negative correlation with relative humidity, the stable isotope values in precipitation are positive correlations with temperature, precipitation and water vapor pressure. Influenced by water vapor source, the values of d-excess are lower for the Westerly wind and the South Asia Monsoon onJuly and the Westerly wind and the East Asia Monsoon on August, but they are higher for the Westerly wind on other months, that they are also influenced by the weather conditions in rainfall process. The variation of stable isotope in precipitation exhibited significant temperature effect, and there is also some precipitation amount effect in spring and summer.

关键词： stable isotope Precipitation Water vapor source Qilian Mountains

Inferring trophic variation for Antarctic krill(Euphausia superba) in the Antarctic Peninsula from the austral fall to early winter using stable isotope analysis

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Acta Oceanologica Sinica 2018年第6期37卷 90-95页

作者： ZHU Guoping ZHANG Haiting SONG Qi YANG Yang WANG Shaoqin YANG Qingyuan College of Marine Sciences Shanghai Ocean University Shanghai 201306 China National Engineering Research Center for Oceanic Fisheries Shanghai 201306 China Polar Marine Ecosystem Group Key Laboratory of Sustainable Exploitation of Oceanic Fisheries Resources Shanghai Ocean University Ministry of Education Shanghai 201306 China

The Antarctic krill（Euphausia superba） is a key species in the Southern Ocean ecosystem and an important link in the food web of the Antarctic ecosystem. The trophic information for this species during the transition from the austral fall to the winter is important to understand its poorly known overwintering mechanisms. However, the few studies on the topic differ in their results, in terms of both spatial and temporal variables. We investigated the size dependence and monthly and regional variation in δ^（13） C and δ^（15） N values of adult krill in the Antarctic Peninsula, in the austral fall（April to May） and the early winter（June）. We aimed to examine the trophic variations of krill occurred during this period, and the relationship between krill and their feeding environment in the Antarctic marine ecosystem. The following results were obtained：（1） no significant relationship was observed between size and the δ13 C value of krill, but the δ15 N value of krill presented a remarkable association with size;（2）the δ13 C values of krill increased during the austral fall, but no remarkable variation existed at the onset of winter,and the δ15 N values were not significant different during this period;（3） mean δ15 N values of krill differed significantly between the Bransfield Strait and the South Shetland Islands. Our data imply that adult krill present size-, season-, and region-dependent trophic variation during the transition from austral fall to early winter in the Antarctic Peninsula.

关键词： Euphausia superba stable isotope trophic variation Antarctic Peninsula feeding habit

Application of stable isotope Techniques in Studies of Carbon and Nitrogen Biogeochemical Cycles of Ecosystem

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Chinese Geographical Science 2011年第2期21卷 129-148页

作者： SUN Zhigao MOU Xiaojie LI Xinhua WANG Lingling SONG Hongli JIANG Huanhuan Key Laboratory of Coastal Environment Processes of Chinese Academy of Sciences Shandong Provincial Key Laboratory of Coastal Zone Environmental Processes Yantai Institute of Coastal Zone Research Chinese Academy of Sciences Yantai 264003 China Key Laboratory of Wetland Ecology and Environment Northeast Institute of Geography and Agroecology Chinese Academy of Sciences Changchun 130012 China Graduate University of Chinese Academy of Sciences Beijing 100049 China Shandong Institute of Agriculture Sustainable Development Jinan 250100 China

stable isotope techniques have been proved useful as tools for studying the carbon (C) and nitrogen (N) biogeochemical cycles of ecosystem. This paper firstly introduced the basic principles and the distribution characteristics of stable isotope, then reviewed the recent advances and applications of stable isotope in the C and N biogeochemical cycles of ecosystem. By applying the 13 C natural abundance technique, ecologists are able to understand the photosynthetic path and CO 2 fixation of plants, the CO 2 exchange and C balance status of ecosystem, the composition, distribution and turnover of soil organic C and the sources of organic matter in food webs, while by using the 13 C labeled technique, the effects of elevated CO 2 on the C processes of ecosystem and the sources and fate of organic matter in ecosystem can be revealed in detail. Differently, by applying the 15 N natural abundance technique, ecologists are able to analyze the biological N 2 -fixation, the N sources of ecosystem, the N transformation processes of ecosystem and the N trophic status in food webs, while by using the 15 N labeled technique, the sources, transformation and fate of N in ecosystem and the effects of N input on the ecosystem can be investigated in depth. The applications of both C and N isotope natural abundance and labeled techniques, combined with the elemental, other isotope ( 34 S) and molecular biomarker information, will be more propitious to the investigation of C and N cycle mechanisms. Finally, this paper concluded the problems existed in current researches, and put forward the perspective of stable isotope techniques in the studies on C and N biogeochemical cycles of ecosystem in the future.

关键词： stable isotope isotope fractionation isotope natural abundance biogeochemical cycle carbon nitrogen