大气中磷化氢的源与汇及其形成机理     

李建兵  张桂玲  张经  刘素美  任景玲 《海洋湖沼通报》2010,(1)

研究天然环境中的磷化氢将会加深对磷的生物地球化学循环的认识,同时对于认识和解决当前环境中富营养化、生物除磷等问题提供一定的参考和帮助。通过对近30a相关研究工作的分析,介绍了大气中磷化氢的各种源与汇及磷化氢测定方法,阐述了磷化氢形成的热力学和微生物学机理,并探讨了磷化氢研究中存在源汇不全面、生物化学形成机理不清楚、水体样品检测方法、生态及其毒理效应等问题,这些问题也将是未来的研究重点。  相似文献   

Chemical and spectroscopic characterization of dissolved humic substances in a mangrove-fringed estuary in the eastern coast of Hainan Island, China   总被引：1，自引：0，他引：1  

张耀玲  杜金洲  彭浡  张芬芬  赵欣  张经 《中国海洋湖沼学报》2013,31(2):454-463

Mangrove-derived dissolved organic matter(DOM) has an important effect on estuarine and coastal area on a large scale.In order to improve the understanding of origin,composition,and fate of DOM in mangrove-fringed estuarine and coastal areas,dissolved humic substances(DHS) were isolated from one mangrove pore-water sample and one near-shore seawater sample downstream the mangrove pore-water site in the eastern coast of Hainan Island,South China.Fulvic acids,humic acids and XAD-4 fractions were obtained from the two water samples by using a two-column array of XAD-8 and XAD-4 resins.Chemical and spectroscopic methods were used to analyze the features of these DHS.Compared to the mangrove pore-water DHS,the near-shore seawater DHS were found rich in 13 C with lower C/N ratios and more aliphatic compounds and carbohydrates,but less aromatic structures and carboxyl groups.As for the three fractions of the two DHS,XAD-4 fractions contain more aliphatics,carbohydrates,carboxyl groups,and enrich in 13 C with respect to both fulvic and humic acids.Photo-oxidation transformation and contribution from marine-derived DOM were considered as the main reasons resulted in the difference in compositional features for these DHS in this study.  相似文献   

海洋中锰的生物地球化学循环研究          下载免费PDF全文

任景玲  张桂玲  刘素美  王召伟  张经 《海洋科学进展》2012,30(3):432-440

痕量元素在海洋生物地球化学循环中起的作用已受到越来越广泛的关注,近年来形成了新的国际科学计划———痕量元素及其同位素的海洋生物地球化学研究(GEOTRACES)。锰是GEOTRACES关键参数之一,国际GEOTRACES组织推荐各国组织的GEOTRACES航次对其在全球大洋中的分布进行重点研究。本研究就痕量元素锰的海洋生物地球化学研究进行了较为详细的综述,介绍了锰在海洋中的来源及输送通量、分布、水体中的赋存形式及其迁移转化、生态学功能以及主要的分析方法等。总结了在这一研究领域所取得的成果及存在的不足,并对今后的发展方向进行展望。  相似文献   

鸭绿江口溶解有机碳的研究   总被引：3，自引：2，他引：1  

王江涛  于志刚  张经 《中国海洋大学学报(自然科学版)》1998,(3)

１９９６年５月采样测定鸭绿江口溶解有机碳（ＤＯＣ）的含量，得出分布变化特征，并同其它一些河口的溶解有机碳进行了比较。鸭绿江口表层水溶解有机碳的平均含量为２０８μｍｏｌＣ／Ｌ。在盐度大于１．６的河口区，溶解有机碳的分布主要受海水稀释作用控制；在盐度０～１．６的区域溶解有机碳的浓度随盐度的增加而明显增加。在最大混浊带，ＤＯＣ的浓度最高，表明有颗粒有机碳转化为溶解有机碳。丹东市以上流段，河水中溶解有机碳的含量相对较低，说明由丹东市引入的工业及生活污水对鸭绿江水体中溶解有机碳的含量有一定的影响。  相似文献   

沉积物中重金属的归一化问题——以Al为例   总被引：21，自引：0，他引：21  

刘素美  张经 《海洋学研究》1998,16(3):48-55

沉积物的来源、粒度和矿物组成是影响重金属在动力沉积过程中的行为的最显著的因素，用某些参考元素（如Ａｌ、Ｌｉ等）归一化的目的是为了减小沉积物中重金属含量的波动，以揭示人文活动（例如污染）的影响。通过对国内一些河流沉积物中重金属的Ａｌ归一化结果的分析，认为在岩石的风化和变质过程中元素与Ａｌ的相对迁移能力的差异和各种生物过程均可使重金属的Ａｌ归一化值产生显著的变化，在某些情况下Ｍ／Ａｌ值并不一定能准确地描述人类活动对沉积物中重金属的影响。Ａｌ归一化仅能部分地校正粒度分布引起的重金属含量的变化，但不能消除矿物组成的影响。  相似文献   

天然水体中微量过氧化氢的测定方法   总被引：1，自引：0，他引：1       下载免费PDF全文

魏西会  刘素美  张经  任景玲  张桂玲 《海洋科学》2008,32(10):96-100

天然环境中的H2O2与水体中的光化学反应、氧化还原反应有密切关系，是影响化学物质（金属离子、腐殖质等）在水环境中的迁移、转化、归宿及生态效应的重要因素，也是酸雨形成的主要原因之一。地表天然水中的H2O2主要来自表层水中可溶解有机物（DOM）的光化学反应，  相似文献   

Preliminary comparison of trace metals in coastal aerosols between Qingdao and Liverpool     

刘昌岭  张经 《中国海洋湖沼学报》2008,26(2):203-214

Aerosol samples were collected at two coastal suburban stations, Qingdao （China） in 1995-1996 and Liverpool （U.K.） in 1995, respectively. The samples were analyzed to determine the concentrations of trace metals （Cr, Zn, Cu, Co, Ni, Pb, V, and Cd） as well as A1, Fe and Mn. Data were examined to understand the difference of trace metals in aerosols between coastal zones downwind the developing area （near the Yellow Sea） and developed region （near the Irish Sea）. The results show that most elements at Qingdao have levels 4-5 times higher than those at Liverpool, particularly for the crust-dominated elements （e.g. Al, Fe and Mn）. Moreover, the aerosol composition at Qingdao is higher in spring than in summer, underlying the influence of westerlies and local emissions in combination, whereas seasonal change of aerosol composition is not significant at Liverpool. The enrichment factors for the crustal source elements （EFcrust） at Liverpool are much higher than those at Qingdao. The contributions from the pollutant source （Rp） for some trace metals like Cu, Pb, Zn and Cd are 〉90% at Qingdao and Liverpool, suggesting overwhelming anthropogenic contributions to these metals. The contributions from crustal source （Re） for trace metals tend to increase with higher aerosol levels and Al concentration at Qingdao, indicating a good correlation between the crust-dominated component and the air mass. At Liverpool, the Rc values for trace metals are positively correlated with Al concentrations instead of with aerosol mass, suggesting that Al in aerosols represents the crustal component even though the aerosols come from different sources.  相似文献   

Examination of Daytime Length''''s Influence on Phytoplankton Growth in Jiaozhou Bay, China   总被引：4，自引：0，他引：4  

杨东方  高振会  张经  崔文林  石强 《中国海洋湖沼学报》2004,22(1)

1　INTRODUCTIONSystematicstudyisusefulforhumanvisualizationandcomprehensionofanetworkofcomplicatedcompo nentsandprocessesinvolvingfrequentenergyflow ,consideringenergyasthebasisofbothstructureandprocess (Automa ,1 993) .Energylanguageisaconceptfordepictingasysteminwhichallphenomenaareac companiedbyenergytransformation .Thefunctionoftheecosystemovertheworlddependsontheenergyfixationbymarineplantphotosynthesis ,mostofthemarefixedbymicrophytoplanktonnearseasurfaceexposedtosunlight (Niebaken …  相似文献   

Benthic nutrient recycling in shallow coastal waters of the Bohai Sea   总被引：3，自引：0，他引：3  

刘素美张经  陈洪涛T.Raabe 《中国海洋湖沼学报》2004,22(4):365-372

Sediment-water fluxes of N and P species in the Bohai Sea were investigated in September-October 1998 and April-May 1999. The benthic fluxes of nutrient species were determined by incubating sediment core samples with bottom seawater bubbled with air or nitrogen. NO^-2,NH4, dissolved organic nitrogen (DON) and phosphorus (DOP), total dissolved nitrogen (TDN) and phosphorus (TDP), and PO4^3- showed a net exchange flux from seawater to sediment, while NO^-3, dissolved inorganic nitrogen (DIN) and SiO3^2- were released from sediment to seawater in the Bohai Sea. Sediment-water nutrient exchange increases DIN and reduces the phosphorus load in the Bohai Sea. The release of silicate from sediment to overlying seawater reduces potential silicate limitation of primary production resulted from decrease of riverine discharge.The exchange flux of nutrients showed no obvious seasonal variation. The present study showed that the concentrations and composition of nutrients in the water column were affected by suspended sediment, and that not all the exchangeable phosphate in sediment could be released via sediment resuspension.  相似文献   

EXAMINATION OF SILICATE LIMITATION OF PRIMARY PRODUCTION IN JIAOZHOU BAY, CHINA Ⅰ. SILICATE BEING A LIMITING FACTOR OF PHYTOPLANKTON PRIMARY PRODUCTION   总被引：1，自引：0，他引：1  

杨东方  张经  吕吉斌  高振会  陈豫 《中国海洋湖沼学报》2002,20(3)

Jiaozhou Bay data collected from May 1991 to February 1994, in 12 seasonal investigations, and provided the authors by the Ecological Station of Jiaozhou B ay, were analyzed to determine the spatiotemporal variations in temperature, light, nutrients (NO-3-N, NO-2-N, NH+4-N, SiO2-3-Si, PO3-4-P), phytoplankton, and primary production in Jiaozhou Bay. The results indicated that only silicate correlated well in time and space with, and had important effects on, the characteristics, dynamic cycles and trends of, primary production in Jiaozhou Bay. The authors developed a corresponding dynamic model of primary production and silicate and water temperature. Eq.(1) of the model shows that the primary production variation is controlled by the nutrient Si and affected by water temp erature; that the main factor controlling the primary production is Si; that water temper ature affects the composition of the structure of phytoplankton assemblage; that the different populations of the phytoplankton assemblage occupy different ecologica l niches for C, the apparent ratio of conversion of silicate in seawater into phytoplankton biomas and D, the coefficient of water temperature's effect on phytoplankton biomass. The authors researched the silicon source of Jiaozhou Bay , the biogeochemical sediment process of the silicon, the phytoplankton predominan t species and the phytoplankton structure. The authors considered silicate a limit ing factor of primary production in Jiaozhou Bay, whose decreasing concentration of silicate from terrestrial source is supposedly due to dilution by current and up take by phytoplankton; quantified the silicate assimilated by phytoplankton, the intrins ic ratio of conversion of silicon into phytoplankton biomass, the proportion of silicate uptaken by phytoplankton and diluted by current; and found that the primary production of the phytoplankton is determined by the quantity of the silicate assimilated by them. The phenomenon of apparently high plant-nutrient concentrations but low phytoplankton biomass in some waters is reasonably explained in this paper.  相似文献