首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 890 毫秒
1.
研究深海沉积物中化学元素的组成及其分布规律,将对海洋沉积物的组成、沉积过程以及辨别沉积岩和现代松散堆积物的形成环境等提供一定的依据。为此,我们曾对我国1976—1979年在太平洋中部所采集的30个表层沉积样和两个柱状样进行了碳酸盐、CaO、MgO等项化学分析测定工作。分析结果表明,这些元素与水深、沉积物类型及生物贝壳、微体生物等有密切关系。而水深、沉积物的类型是这些元素分布特征的重要控制因素。  相似文献   

2.
研究海洋底质间隙水中化学元素的存在形态及沉积物与间隙水之间的化学交换反应,对阐明海洋底质间隙水溶液的成岩作用、元素海洋地球化学过程以及海洋污染物质的转移机理,都具有极为重要的意义。 从底质泥样中提取间隙水的方法大致可分为四种,即压滤法、离心法、稀释法和有机溶  相似文献   

3.
海洋沉积物作为生源要素氮的重要源与汇,在其生物地球化学循环中起着至关重要的作用。该项研究旨在查清海洋沉积物中氮的存在形态及其生态学意义。氮是生物生命活动必需的营养要素,海洋中的氮往往是海洋初级生产力的限制因子,氮的吸收与再生释放在估算海洋新生产力和生源要素的生物地球化学循环率上也有重要贡献。海洋沉积物中的氮作为海水中氮的重要供给源是海洋生物赖以生存的重要物质基础,对维持海洋生态平衡、修复失衡的海洋生态环境具有重要意义。但由于不同海区海洋沉积物的来源和环境不同,氮的形态和含量亦不相同,可被生物吸收和利用的数量就不相同,因此造成了不同海区生物种群和环境不同,进而影响生态环境。因此,研究海洋沉积物中氮的形态,了解各个形态与沉积物中生物种群及与环境的关系,确定其生物和化学活性,査清氮不同形态的生态学功能,对于深入探讨海洋生物资源可持续利用的方法和策略具有重要意义。本文主要阐述海洋沉积物中氮的存在形式与分布、氮的早期成岩和去营养化作用、硝化和反硝化作用以及氮与生物特定种群的关系等,探讨了影响海洋沉积物中的氮循环的主要因素,并分析了海洋沉积物中的氮与生态系的关系,以期对研究氮的海洋生物地球化学过程有所帮助。  相似文献   

4.
在过去几十年里,为了探索海洋沉积物中元素的赋存形态,发展了很多分离沉积物中不同元素结合态的淋滤萃取方法。这些方法对于了解沉积物中微量元素的来源、迁移、分散、活动、生物化学及物理化学行为等特征具有重要的意义,并且在海洋地球化学和海洋环境污染研究中已得到广泛应用。本文综合论述了海洋沉积物的顺序淋滤萃取分析方法的研究进展,介绍了两种影响较大的方法,对其选用的萃取试剂以及分析流程进行了详细讨论,并比较了方法的优点和不足。  相似文献   

5.
海洋沉积物中的植物信息具有重要的生态学和古环境意义,但传统方法只能通过研究沉积物中的孢粉获取植物信息。随着分子生物学的进步,探索利用海洋沉积物中的植物分子多样性解释全球变化成为了一种新的尝试。文章首次尝试了对海洋沉积物中的植物DNA进行提取与PCR扩增,通过使用不同的DNA提取方法(DNA提取试剂盒)和PCR扩增条件[2倍浓缩的PCR扩增预混合溶液(Mix)退火温度、循环数、DNA模板量以及引物],探索海洋沉积物中植物DNA提取和PCR扩增的方法,并在采自黄海潮间带以及浅海表层的沉积物中进行了检验。共尝试了32种方法,结果表明:强力土壤微生物DNA提取试剂盒(DNeasy PowerSoil)以及2×TransTaq HiFi PCR SuperMixⅠ是较好的DNA提取与扩增条件;对于潮间带表层沉积物样品,最佳退火温度为55°C,最佳循环数为55个循环;而对于浅海表层沉积物样品,最佳退火温度为59°C,最佳循环数为45个循环;此外,相对于rbcL引物, gh引物的扩增结果更好。这项研究首次成功提取并扩增了海洋沉积物中的植物DNA,以期应用于海洋沉积物中植物分子多样性的分析,为研究全球...  相似文献   

6.
根据黄河下游及黄河口表层沉积物的39种元素含量和分布,讨论了它们的相关、非相关和无相关特性;通过黄河下游、黄河口和渤海湾大量元素的对比,阐明了元素分布的若干特点。按照化学元素的周期性和地球化学特性对39种元素进行了分组,这种分组能较好地说明和预测海洋沉积物中元素的分布规律。  相似文献   

7.
甲藻孢囊研究进展   总被引:7,自引:0,他引:7  
孢囊的形成是某些海洋甲藻生活史中的重要阶段,尤其是甲藻在不良环境条件下使个体度过逆境的阶段,它对种群的保存和延续有重要的意义.孢囊被普遍认为是赤潮发生的"种源"以及外来种类的主要来源之一,它对赤潮的发生、延续和消亡过程有着重要的作用.大多数的甲藻孢囊具有含孢粉类似物的抗性细胞壁,可以长期保存在底部的沉积物中,所以被广泛地应用于中世纪以来的沉积物生物地层学和古生态学的考察中.对甲藻孢囊的研究,目前是海洋生态学、海洋地质学、海洋环境学的研究热点.本文阐述了国内外近些年来对甲藻孢囊研究的主要进展,内容主要集中在甲藻孢囊的研究方法、形态分类、空间分布、原位动力学以及孢囊与海洋环境关系方面的研究.  相似文献   

8.
渤海沉积物中的矿物组合及其分布特征的研究   总被引:12,自引:1,他引:12  
海底沉积物中矿物组分的研究对阐明沉积作用的过程具有重要意义。它不仅可以说明沉积物的物质组成、分布规律以及沉积物的物质来源,而且可进一步了解蚀源区的母岩成分及矿物在搬运过程中的变化规律。因此,矿物组合及其迁移变化规律的研究便成为海洋沉积学的重要内容之一。  相似文献   

9.
海底沉积物碎屑矿物数据是海洋地质领域的重要基础资料,它在海洋沉积作用、环境演变研究以及海底砂矿资源勘 探中具有突出的意义。在系统分析了碎屑矿物特征和不同时期碎屑矿物鉴定差异的基础上,探讨了影响碎屑矿物数据整合的 主要因素,构建了海底沉积物碎屑矿物数据整合的技术体系,包括碎屑矿物数据格式制定、规范性处理、数据质量控制以及 数据重复性检查等方面,提出了 3级数据排重模式,并对数据整合的深入开展进行了探讨。该研究成果有利于促进海洋地质 工作规范化以及历史调查数据的充分利用,同时也为海底沉积物其他类型资料的整合提供参考。  相似文献   

10.
本文根据杭州湾北岸潮滩30个站位沉积物的化学元素测定,对潮滩沉积物的化学特征,分布规律及其影响因素进行分析。发现潮滩沉积物中的微量元素存在明显的分带性,这种分带同沉积物的粒度、化学性质及其水动力条件有一定相关性。  相似文献   

11.
Dissolved, weakly and strongly bound particulates Cu, Pb, Zn, Cd, Co, Ni and Fe have been measured in the surface water sampled from eleven stations in Xiamen Harbor by clean laboratory methods and GFAAS. The average concentrations found in dissolved fractions are Cu: 0.41±0.12; Pb: 0.014±0.008; Zn: 0.084±0.043; Cd: 0.022±0.004; Co: 0.009±0.004; Ni: 0.15±0.02; and Fe: 0.15± 0.02 μg/kg, which make up 62%, 6%, 12%, 85%, 5%, 25% and <1% of the total metals in the surface water respectively. The results are mucn lower than those reported previously in the coastal waters of China. Industrial sources of trace metal contamination are likely responsible for the distribution of trace metals.  相似文献   

12.
Baltic surface water was sampled at a fixed position at intervals of a few hours. The trace metal concentrations were measured by graphite furnace AAS after extraction. The mean concentrations found were (ng l?1): Cd, 30 ± 2.7; Cu, 800 ± 48; Fe, 358 ± 165; Ni, 820 ± 49; Pb, 16 ± 4.5; Zn, 900 ± 160. The variability in the trace metal concentrations is of the same order of magnitude as the precision of the method. Thus, no spatial variations in trace metal concentrations were found.  相似文献   

13.
The crude enzyme, which was extracted from viscera of Lunella coronata coreensis (Recluz), was salted out and dialysed. Three enzymatic peaks isolated from DEAE-cellulose column chromatography were refered to as lyase Ⅰ, Ⅱ and Ⅲ, respectively. Then these lyases underwent gel-filtration on Sephadex G-25 respectively, and three purer lyases were derived therefrom, the highest purification being 73 fold.The kinetics of the three lyases was tested respectively. The optimum pH was as follows: lyase Ⅰ was 7.6±0.02 Tris-HCl buffer; lyase Ⅱ was 6.6±0.02 Na2HPO4-NaH2PO4 buffer; and lyase Ⅲ was 5.6±0.02 HAc-NaAc buffer. In the rang of tested concentration, KC1 and Nad were the activator and MnCl2 was the inhibitor, all for the three lyases; MgCl2 was the activator for lyases Ⅰ and Ⅱ, but the MgCl2 of high concentration was the inhibitor for lyase Ⅲ; Pb (OAc)2 acted differently for three lyases. The Km values of these lyases were 0.2, 0.6 and 0.04 mg/ml in order of precedence.  相似文献   

14.
泥蚶(Tegillarca granosa)肉质的蛋白组学研究   总被引:2,自引:1,他引:1  
采用双向电泳技术,对广东阳江和浙江乐清两地的泥蚶肌肉全蛋白进行了研究,并利用质谱和软件对差异蛋白进行了分析.研究结果表明,阳江和乐清两地样品平均检测到的蛋白点数分别为674±25和746±34个,平均匹配率为78.6%.差异表达蛋白质点数为26个,其中3个点仅在阳江泥蚶中表达,5个点仅在乐清泥蚶中表达;6个点在阳江泥蚶中为高表达,12个点在阳江泥蚶中为低表达.选择其中6个具有代表性的蛋白点进行肽指纹图谱分析.结果显示,乐清泥蚶中高表达的4个蛋白确定为肌动蛋白、PRKA激酶锚定蛋白9、烯醇化酶.这些物质与泥蚶的肉质特性有一定关联.乐清地区出产的泥蚶在营养、肉质和鲜美度方面均优于阳江地区的泥蚶.  相似文献   

15.
Suspended matter was collected at 30 stations in the Baltic and Kattegatt, at the thermocline and at the bottom, and analysed for Na, Ca, Mg, Si, Ti, Al, Fe, Mn, Ba, Sr, Ni and V. The composition of the suspended matter varies considerably, but can be described as a mixture of: (1) 12–25% terrigenous detritus with much Si, Al, Ti and Fe; (2) 75–88% biological matter with much Ni, V and Ba; and (3) some Mn-oxyhydroxide.The annual efflux of water from the Baltic is about 460 km3, with a suspended load in the Baltic straits of ~1.2–3.6 mg ash material l?1 These values imply that much Si, Ti, Al, Fe, Sr, Ni and V and particularly much Ba and Mn are lost from the Baltic in the suspended load.The average suspended matter is richer in Mn(5×), Ba(2.5×), Sr(4×) and V(1.8×) than permanently depositing Baltic sediments. These constituents are relatively enriched in pelagic deposits, i.e. it is likely that much Mn, Ba and V in deep-sea sediments derive from the continents via suspended transport. This conclusion is supported by the similarity between suspended matter and average Atlantic pelagic sediment.  相似文献   

16.
海洋生物样品中硒的氢化物发生-原子荧光分析(HG-AFS)   总被引:2,自引:0,他引:2  
采用硼氢化钠还原法将试样中硒还原为挥发性硒化氢 ,氩为载气将硒化氢吹出并导入火焰原子化器进行原子荧光测定。以正交设计法对该还原反应、氢化物转移、原子化及原子荧光测定条件等进行了详细研究。实验结果表明 ,在佳化条件下 ,该法检出限为 0 .0 72μ g/ dm3,相对标准偏差为 2 .0 %。标准曲线表明 ,在 0 .0 0 0~ 1.0 0 0μ g/ dm3Se浓度范围内 ,有理想的线性关系。本法测定海洋生物样品硒的回收率为 95.8%~ 10 2 .4 %。  相似文献   

17.
The different mineral phases of the ferromanganese (Fe–Mn) crusts stem from the interaction of biotic and abiotic components. It is therefore vital to study the activity of these components to decipher their contribution to the enrichment/depletion of metals in the crust. Thus, the present study examined sorption and release of Co and Ni by Fe-Mn crusts with associated microbial communities in the presence and absence of the metabolic poison sodium azide (15?mM). The study was conducted in the presence (G+) and absence (G?) of added glucose (0.1%) at temperatures of 4?±?1°C and 28?±?2°C. Results showed that the microbial community had maximal sorption of Co of 66.12?µg?g?1 at 4?±?1°C in the absence of added glucose and 479.75?µg?g?1 at 28?±?2°C in the presence of added glucose. Maximum sorption of Ni in the absence of added glucose was 1.89?µg?g?1 at 4?±?1°C and release of Ni was 51.28?µg?g?1 in the presence of added glucose. Under abiotic conditions with 15?mM sodium azide as a metabolic inhibitor, significant amounts of Co and Ni were released in the G+ medium. Total cell counts on the Fe-Mn crust in the presence of added glucose increased by an order of magnitude from 106 to 107 cells g?1 and in the absence of added glucose remained within the order of 106 cells?g?1 irrespective of temperature of incubation. Microscopic observation of the samples from biotic incubations showed numerous bacterial cells, exopolysaccharides, and structures resembling secondary minerals formed by bacteria. The results indicate that bacteria promote the enrichment of Co and Ni on the hydrogenetic Fe-Mn crusts by sorption processes and release of Ni by reductive dissolution of the oxides. The higher enrichment of Co than Ni is attributed to the way in which microbes interact with the metals.  相似文献   

18.
三亚湾滨珊瑚骨骼重金属与环境因子的关系   总被引:3,自引:0,他引:3  
利用ICP-AES分析测定了南海北部三亚湾滨珊瑚(Porites)骨骼生长带1977—1999年问重金属Cr、Zn、Cd、Cu、Ph、Ni、V的含量。通过对重金属元素的因子分析,划分出2类元素组合:Zn、Cd、Cu、Ph、Ni组合和Cr、V组合。2类重金属元素组合与不同季节表层海水温度、降水量以及冬、夏季风指数等相关环境因子的逐步回归分析反映出具不同的重金属元素有不同的环境影响因子,其中Zn、Cd、Cu、Ph、Ni组合主要受春季表层海水温度的影响.Cr、V组合主要受冬季风强弱变化的影响。  相似文献   

19.
Measurements of carbon in marine “net zooplankton” were made by use of a Leco 70 Second TC-12 Automatic Carbon Determinator. The instrument employs high-temperature (ca. 1600°C), dry-combustion and thermal-conductivity detection of the purified carbon-dioxide combustion product and oxygen carrier gas mixtures. The methodology developed in this study is convenient and rapid (ca. 70 sec per freeze-dried sample), with a mean error (±2σ/x ·100) of ±4.4% at the 3 mg-C level and ±7.4% at the 10 mg-C level when benzoic acid is used as a standard, and ±9.2% at the 5 mg-C level and ±6.0% at the 10 mg-C level when casein is used as the standard. The technique was applied to the “splash zone” marine copepod Tigriopus californicus to obtain an average value of 38.6% C by weight. Concentrated samples of “net zooplankton” of varying size fractions were collected in the Monterey upwelling region over an eight-month period. Values up to 2000 mg-C/m2 ocean surface (0–200 m) were observed in a seasonal cycle doubly peaked for some size fractions but not for others.  相似文献   

20.
1989年5月及10月测定青海湖主要经济鱼类青海湖裸鲤Gymnocypris przewalskii przewalskii(Kessller)不同性别,9种组织中的人体及动物必需常量元素6种,微量元素10种的含量。存在不同组织、性别、季节及年份的差异。雌鱼常量元素总量是骨>鳞>鳃>肝>肌肉>肠>心>卵巢>皮;微量元素总量肠>鳞>心>鳃>骨>肝>皮>卵巢<肌肉。雄鱼常量元素总量是骨>鳞>鳃>皮>精  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号