Orthogonal design for optimization of pigment extraction from surface sediments of the Changjiang River Estuary   总被引：1，自引：0，他引：1  

ZHAO Jun  YAO Peng  YU Zhigang  Thomas S Bianchi 《海洋学报(英文版)》2011,30(4):33-42

Using a suitable solvent for extracting pigments from sediment for high performance liquid chro-matography (HPLC) analysis is critical for obtaining qualitative and quantitative estimates of phytoplanktonic and benthic algal biomass, as well as community composition. Five methodolog-ical factors (sample dehydration, extraction solvent, extraction duration, number of extractions, and ratio of solvent volume: sample weight) were studied using an L₉ (3⁴) orthogonal design in a sedimentary pigment extraction experiment on samples collected from the Changjiang large-river delta-front estuary (LDE), using HPLC analysis. The results show that the optimal extraction method for sedimentary pigments should include freeze-drying samples prior to extraction. The effects of different factors on sedimentary pigment extraction were separated by the L₉ (3⁴) or-thogonal design experiments and showed that the extraction solvent was the most important, with extraction duration the second most important, and numbers of extraction and ratio of solvent vol-ume: sample weight was the least important. The mixed solvent treatment comprised of acetone, methanol and water (80:15:5, by volume) was best for polar pigment extraction, with 100% acetone better for apolar pigments. For most pigments employed in this study (i.e., peridinin, fucoxanthin, alloxanthin, diatoxanthin, zeaxanthin, pheophytin-a and β-carotene), 3 h was found to be enough time for extraction from these deltaic sediments. However, for chlorophyll-a, the most important pigment used for estimating algal biomass, 12 h was needed. A small amount of solvent (3 ml) with duplicate extractions obtained the greatest amount and diversity of pigments. Unfortunately, no extraction method was found to be suitable for all pigments in sediments. The choice of extraction procedure should be made in accordance with the objective of each study, taking into consideration the properties of sediments and pigments in question.  相似文献   

Study on the analysis and distribution of dimethylsulfoxide in the Jiaozhou Bay   总被引：1，自引：0，他引：1  

YANG Jie  YANG Guipeng  YANG Jian 《海洋学报(英文版)》2011,30(6):36-45

A chemoreduction-purge-and-trap gas chromatographic method has been developed for the determination of trace dimethylsulfoxide (DMSO) in seawater. In the analysis procedure, DMSO was first reduced to dimethylsufide (DMS) by sodium borohydride and then the produced DMS was analyzed using the purge-and-trap technique coupled with gas chromatographic separation and flame photometric detection. Under the optimum conditions, 97% DMSO was reduced in the standard solution samples with a standard deviation of 5% (n=5). The detection limit of DMSO was 2.7 pmol of sulfur, corresponding to a concentration of 0.75 nmol/L for a 40 ml sample. This method was applied to determine the dissolved DMSO (DMSOd) and particulate DMSO (DMSOp) concentrations in the surface seawater of the Jiaozhou Bay, and the results showed that the DMSOd and DMSOp concentrations varied from 16.8 to 921.1 nmol/L (mean:165.2 nmol/L) and from 8.0 to 162.4 nmol/L (mean:57.7 nmol/L), respectively. The high concentrations of DMSOp were generally found in productive regions. Consequently, a significant correlation was found between the concentrations of DMSOp and chlorophyll a, suggesting that phytoplankton biomass might play an important role in controlling the distribution of DMSOp in the bay. Moreover, in the study area, the concentrations of DMSOd were significantly correlated with the levels of DMS, implying that the production of DMSOd is mainly via photochemical and biological oxidation of DMS.  相似文献   

长江口及邻近海域夏季表层沉积物中重金属等的分布、来源与沉积物环境质量   总被引：1，自引：0，他引：1       下载免费PDF全文

何松琴  宋金明  李学刚  刘志刚 《海洋科学》2011,35(5):4-9

通过现场调查研究报道了长江口及邻近海域表层沉积物中重金属、有机碳、石油类、硫化物以及氮磷的分布、来源以及沉积物环境质量.结果显示,长江口及邻近海域表层沉积物中重金属、有机碳、石油类、硫化物以及氮磷的分布很不均匀,除硫化物外,重金属、有机碳、石油类以及氮磷基本呈现长江口和杭州湾东北近岸的上海外海出现高值,其他区域浓度较低...  相似文献   

福岛——为了忘却的纪念     

姜周熙 《海洋世界》2011,(3):40-43

大地震前的福岛美景位于日本东北福岛县的五色沼(Lake Goshikinuma),也有日本九寨沟的美誉,湖水洁净无瑕,随不同的气候和时间,而呈现变幻莫测的颜色。五色沼是磐梯火山于1888年爆发所形成的火山湖。由于湖中含有丰富的矿物质,湖水随不同的气候而产生化学变化,经阳光折射而出现翡翠、钻蓝和鲜绿等神秘色调,湖水中还有很多硕大的鲤鱼游弋,悠然自得。  相似文献   

海洋沉积硅藻研究进展   总被引：2，自引：0，他引：2  

吴瑞  蓝东兆  高亚辉  兰彬斌  方琦 《台湾海峡》2011,30(1):142-148

综述了国外近40 a海洋沉积硅藻表层组合及其在地层划分与对比、古地理环境重建、海平面升降和岸线变迁等方面的应用,以及硅藻休眠孢子化石的分类学、地层学和分子系统发育学研究的最新进展.对中国海洋沉积硅藻的研究进展作了概述,基本查明了渤海、黄海、东海、南海4大海区表层硅藻属种组成及表层硅藻组合面貌;利用硅藻组合进行了地层划分与对比、古海洋环境演变过程的研究;并将各种数理统计方法结合到硅藻分析中,使中国海洋沉积硅藻研究逐渐由定性或半定量向定量研究发展.但在利用硅藻进行古环境定量重建等方面,与国外的研究还存在一定差距.今后应加强建立现代硅藻-环境变量数据库、表层沉积生物硅的溶解、硅藻休眠孢子化石的分类学和地层学等方面的研究.  相似文献   

深圳铜鼓航道表层沉积物中重金属含量及潜在生态危害   总被引：1，自引：0，他引：1  

李壮伟  陈巧弟  罗荣真  陈鸿生  刘文辉 《海洋地质前沿》2011,(9):32-39

根据2009年9月深圳铜鼓航道表层沉积物中重金属含量的调查资料,采用单因子指数法和Hakanson生态风险指数法对其重金属污染特征及潜在生态风险进行了分析和评价.结果表明:重金属含量较低,属于国家一类海洋沉积物;表层沉积物已受到重金属Pb、Zn、As的污染,所有站住重金属综合污染指数均＞5,达到中等污染水平,各重金属污...  相似文献   

渤海湾西南部海域表层沉积物分布特征     

李建伟  吴建政  胡日军  朱龙海  张立奎 《海洋地质前沿》2011,(9):11-17

基于渤海湾西南部海域3次表层沉积物调查资料,通过表层沉积物粒度数据研究沉积物类型和分布特征,在空间和时间尺度上探讨沉积物变化规律.结果表明:研究区表层沉积物主要以砂质粉砂和黏土质粉砂为主,西北部沉积物较细,东南部沉积物相对较粗,深水区沉积物较细,浅水区沉积物相对较粗;研究区浅水区分选性好于深水区,东南部分选性好于西北部...  相似文献   

Stable oxygen and carbon isotopes from the planktonic foraminifera Neogloboquadrina pachyderma in the Western Arctic surface sediments： Implications for water mass distribution   总被引：1，自引：0，他引：1  

XIAO Wenshen  WANG Rujian  CHENG Xinrong 《极地研究(英文版)》2011,(4):205-214

  相似文献   

热带次表层海温对中国东部夏季气候的影响     

李晓婧  肖天贵  唐毅 《成都信息工程学院学报》2011,26(1):29-36

热带海洋热状况是影响中国气候变化的主要因子之一,为了研究热带次表层海温如何影响中国气候,通过相关计算和合成分析等方法讨论了热带太平洋至印度洋次表层海温异常对中国东部夏季降水和温度的影响。结果表明:当冬季赤道东印度洋至西太平洋次表层海温偏暖(偏冷),中印度洋和东太平洋次表层海温偏冷(偏暖),夏季,长江中下游地区降水偏少(偏多),华南、华北和东北大部地区降水偏多(偏少);中国东部大范围高温(低温)。其可能的影响途径为,东亚夏季风环流对热带次表层海温异常的响应导致了其年际变化,进而引起中国东部夏季气候的异常分布。  相似文献   

金佛山表层岩溶泉水化学动态变化浅析     

师自龙 《地理教学》2011,(4):32-34

为进一步研究中国亚热带地区表层岩溶水的动态变化规律,了解亚热带岩溶作用机制,通过分析重庆金佛山表层岩溶泉——碧潭泉和水房泉的全自动观测数据,得出以下结论：（1）长时间尺度监测表明,海拔不同的两个泉水之间水化学性质有较大差异。（2）短时间尺度加密观测表明,碧潭泉和水房泉的水化学性质昼夜变化一致,但有区别。（3）在降雨作用下,碧潭泉和水房泉的水化学动态变化一致。（4）两个泉水水位都比较稳定,可以在一定程度上保证附近居民的用水,尤其可用于山顶的旅游开发。研究结论有助于进一步认识表层岩溶水的变化规律,理解亚热带岩溶作用的机理,并且还可以参与到全国表层岩溶对比之中,完善表层岩溶动力系统的分类,指导人们对地表水资源的利用。  相似文献