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991.
本文研究了固定化海带吸附含铜、镉溶液的解吸过程,结果表明:在所选的HCl、HNO3、Na2CO3、NaHCO3 4种解吸剂中,HCl、HNO3均有一定的解吸效果,但HCl比HNO3更适合做解吸剂.当解吸剂盐酸的浓度为0.1mol/dm^3时,解吸率最大,  相似文献   
992.
1999年11月至2000年4月,在中国第16次南极科学考察往返航线上的海域,采集了22个海洋气溶胶样品,用原子吸收分光法测定了样品中的Cu、Pb、Zn、Cd、Fe、A1、Mn、Cr、V、K、Na、Ca、Mg等13种元素的含量.研究表明气溶胶重金属微量元素的分布具有明显的地理区域性.应用元素富集因子、相关分析和因子分析等方法研究了西太平洋、东印度洋、南大洋、中国南极中山站邻近海域气溶胶中各元素的来源.  相似文献   
993.
5种重金属对白脊藤壶无节幼体的急性毒性研究   总被引:2,自引:0,他引:2  
本文研究了铜、锌、镉、汞4种重金属无机离子及1种有机形态的锡对白脊藤壶(Balanus albicostatus)第二期无节幼体的急性毒性效应,报告了各重金属在作用时间为2、4、8、16和24h时的最高无毒浓度、最低有毒浓度、半致死浓度及各有毒浓度产生毒性作用所需的最短作用时间.结果表明所研究的不同化学形态的重金属对白脊藤壶幼体均具较高的毒性,其毒性随重金属浓度及作用时间的增大而呈逐渐上升的趋势.有机形态的锡对白脊藤壶第二期无节幼体的毒性要高于其它4种重金属无机离子的毒性,4种重金属无机离子对白脊藤壶第二期无节幼体的毒性大小顺序为:汞〉铜〉镉〉锌.揭示了白脊藤壶第二期无节幼体的急性毒性实验具灵敏度高、指标明确、方法简便、取材方便、实验周期短、具重要的生态意义等优点,可应用于海洋中若干种重金属的污染监测.  相似文献   
994.
9810号台风影响期间厦门湾海水化学要素变化特征   总被引:2,自引:1,他引:2  
热带风暴是影响我国沿海地区的主要自然灾害之一.由于海洋资源开发利用、海洋环境保护等工作的需要,加之海洋科学观测技术手段的进步,近年来,国内外不少学者致力于热带风暴对近海水文气象、海岸港湾工程建设、水体热交换、海洋生态等方面的影响.台风风场导致海水水体强烈运动,加之其所伴随的暴雨、风暴潮将会极大地加速近岸浅水海域陆-海,河-海,海-空,海水-海底沉积物等界面之间的物质和能量交换,引起海水水化学要素在短期内急剧变化,进而影响海水水质状况以及海洋生物过程,海水养殖和其他海洋资源开发利用.  相似文献   
995.
珠江口淇澳岛红树林区海水中营养盐和叶绿素a研究初探   总被引:3,自引:0,他引:3  
王虎  高航  周怀阳  郭卫东 《台湾海峡》2005,24(4):502-507
2004年4月对珠江口淇澳岛红树林区进行现场调查,分析该区域营养盐和叶绿 素a浓度分布特征,并对两者之间的相关性进行探讨,研究结果表明该区域营养盐及 叶绿素a浓度均较高;而且靠近岛屿、红树植物分布较多的区域,溶解无机氮(DIN) 含量要低于距离岛屿较远、红树植物较少的区域;相关性分析表明叶绿素a与无机氮 化合物之间相关性较好,与磷(PO4-P)、硅(SiO3-Si)之间却无明显相关,说明无机氮 化合物与浮游植物和初级生产力之间关系密切,氮元素及其循环对红树林生态系统 可能起着重要的作用.  相似文献   
996.
The shell chemistry of Isognomon ephippium from three Kenyan sites (Tudor, Gazi and Mida) has been investigated to determine whether these bivalves record environmental parameters. The Mg, Sr, Ba and Mn distributions in the calcite shell layer were determined by using laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS). In addition, whole-shell analyses were made to evaluate inter-site differences. While some variability is observed for mean Mg concentrations, the mean Sr concentrations were similar for the three sites. The decreasing mean Ba and Mn concentrations, following the order Tudor > Gazi > Mida, are related to distinct regimes of freshwater and nutrient supply. The Mg profiles, determined by LA-ICP-MS, displayed a close to regular sinusoidal pattern, depending on specimen and sample site. For the Tudor shells, an arbitrary fitting of the Mg profiles to sea-surface temperature (SST) variations emphasised the good relationship between these two parameters and allowed for the calculation of mean annual growth rates. In most of the shells, Sr partly co-varied with Mg and Ba, highlighting the complexity of Sr incorporation. The Ba and Mn profiles of the Tudor shells displayed several sharp maxima. With a time scale deduced from the Mg–SST relationship, the Ba and Mn maxima of the Tudor shells closely followed periods of maximal rainfall associated with the southeast monsoon. These Ba and Mn maxima were tentatively associated with algal bloom events known to succeed these periods of high rainfall. The less clearly marked seasonality of the Ba and Mn maxima for the Gazi and Mida specimens is thought to result from weaker seasonal variations in nutrient supply and reduced nutrients inputs. This study highlights the potential of I. ephippium as a recorder of spatio-temporal environmental variations in tropical coastal ecosystems.  相似文献   
997.
We have analyzed 33 Pliocene bulk sediment samples from Ocean Drilling Program Site 1085 in the Cape Basin, located offshore of western Africa in the Angola–Benguela Current system, for 17 major and trace elements, and interpreted their associations and temporal variations in the context of an allied data set of CaCO3, opal, and Corg. We base our interpretations on elemental ratios, accumulation rates, inter-element correlations, and several multi-element statistical techniques. On the basis of qualitative assessment of downhole changes in the distributions of P and Ba, utilized as proxies of export production, we conclude that highs in bulk and biogenic accumulation that occur at 3.2 Ma, 3.0 Ma, 2.4 Ma, and 2.25 Ma were caused by increases in export production as well as terrigenous flux, and record a greater sequestering of organic matter during these time periods. Studies of refractory elements and other indicator proxies (SiO2, Al2O3, TiO2, Fe2O3, MgO, V, Cr, Sr, and Zr) strongly suggest that the terrigenous component of the bulk sediment is composed of two compositional end-members, one being ‘basaltic’ in composition and the other similar to an ‘average shale’. The basaltic end-member comprises approximately 10–15% of the total bulk sediment and its presence is consistent with the local geology of source material in the drainage basin of the nearby Orange River. The increase in bulk accumulation at 2.4 Ma appears to reflect a greater relative increase in basaltic input than the relative increase in shale-type input. Although studies such as this cannot precisely identify the transport mechanisms of the different terrigenous components, these results are most consistent with variations in sea level (and associated changes in shelf geometry and fluvial input) being responsible for the changing depositional conditions along the Angolan Margin during this time period.  相似文献   
998.
三种绿藻多糖的提取及理化性质和活性比较   总被引:3,自引:0,他引:3  
采用80℃水浴8h、乙醇沉淀、Sevage法去除蛋白质的方法提取湛江裂片石莼、肠浒苔和总状蕨藻多糖,并用Molish反应、Fehling反应鉴定多糖的化学性质,用苯酚-硫酸法测定多糖的总糖含量,用Dodgson法测定多糖的硫酸基含量,用Folin-酚法测定多糖的蛋白质含量.结果表明:3种绿藻的多糖提取率和多糖总糖含量以裂片石莼最高,分别为3.0%和72.6%,总状蕨藻最低分别为1.65%和38.6%;3种绿藻的硫酸基含量相差不大.总状蕨藻的蛋白质含量最高,为14.5%.3种多糖溶液作用于体外白血病细胞结果以总状蕨藻的抑制效果最明显,浓度为12mg/dm^3的总状蕨藻多糖溶液作用72h的抑瘤率达66%.  相似文献   
999.
广西南流江口海域盐度的锋面特征及其与环境因子的关系   总被引:1,自引:0,他引:1  
本文通过1998年10月和1999年1月、4月、8月4个季度月的调查资料,对南流江口海域盐度锋面特征的形成及其与环境因子的关系进行了分析研究.结果表明:该海域盐度的锋面特征随季节变化较大,春季突出了南流江径流的影响作用,夏、秋季则突出了北上海流和西向沿岸流的顶托影响作用,冬季则由合浦沿岸水及南流江径流综合影响所形成;相关分析显示,盐度与环境因子之间的关系,除径流影响较小的冬季外,多具有密切关系,而且除pH外,均表现为负相关.其中以与溶解态N、P、Si的相关性最好,都达到了高度显著水平,与COD、SS的关系次之,其余形态氮多以良好负相关出现,而形态磷的相关性都表现较差.显然,南流江径流对北海湾溶解性N、P、Si贡献最大,这是导致该湾N明显偏高、P成为赤潮诱发因子、Si成为最丰富营养盐的主要原因.  相似文献   
1000.
This paper examines the presence, distribution, nature and sources of 22 Aromatic Hydrocarbons (PAHs), which are important environmentally and toxicologically, in sediments from the Stagnone coastal lagoon at Marsala (Italy). Analysis was performed by gas chromatography/mass spectrometry (GC/MS) with selected ion monitoring (SIM). The total concentration of polycyclic aromatic hydrocarbons ranged from 72 to 18381 μg/kg of dry matrix. The relative standard deviation (RSD) of the replicates on the concentrations of individual compounds ranged from 5% to 20%. The accuracy of method was estimated by analyzing “blank” samples added of known quantities of analytes and the recover percentage was 88 ± 9%. The detection limit (LOD) of analytical procedure was less than 0.2 μg/kg d.w. for all analytes. The quantification limit (LOQ) of analytical procedure was less than 0.7 μg/kg d.w.The resulting distributions and weight ratios of specific compounds are discussed in terms of sampling location and origin of organic matter. A comparison with other studies of total PAHs suggests that the levels are within the concentration ranges already reported by other authors. From an eco-toxicological point of view, total PAH concentrations at seven out of the eight sites studied represent a relatively clean environment when compared to other sites.Organic matter content and PAH concentrations were found to be correlated and the compounds present in Stagnone sediments were shown to be mainly of pyrolitic origin, while a negligible quantity of PAHs may derive from biogenic sources since all the sediments contain perylene traces. There is no evidence of coal-tar contamination.Cluster analysis was carried out in order to discriminate between different PAH origins.  相似文献   
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