碱度增加对蛋白核小球藻光合活性与胞外多糖的影响

本文研究了不同重碳酸盐(HCO3)碱度2.3mmol/L(ALK2.3)和12.4mmoFL(ALK12.4)条件对蛋白核小球藻光合活性、色素组成、丙二醛(MDA)含量与胞外多糖的影响.实验结果表明,碱度增加对蛋白核小球藻光合活性呈促进一抑制一促进效应,ALK2.3对光合活性影响的强度.高于ALK12.4.碱度增加提高叶绿素b/叶绿素a(Chl.b/Chl.a)的值,降低类胡萝卜素/叶绿素(Caro/TChl)的值,并且ALKl24条件下对藻细胞的作用程度强于ALK2.3.此外碱度增加刺激蛋白核小球藻胞外多糖分泌,ALK2.3在培养初期提高MDA含量,ALK12.4下细胞MDA含量显著降低.说明碱度增加会促进蛋白核小球藻光合活性,促进光合产物的积累与分泌.暗示胞外多糖的分泌可能是细胞适应高碱度的一种自我保护机制.     

台湾地区湖库水酸化之研究

本文旨在探讨酸雨对台湾地区湖泊、水库等自然水域酸化的影响程度。主要内容为建立水域酸化程度之资料，以及不ＰＨ值湖水中，铝离子释放的情形。     

国际间二氧化碳参数之互校

海洋中二氧化碳系统的研究,需要分析pH、总碱度(TA)、总二氧化碳(TCO₂)及二氧化碳分压(pCO₂).但因全球各实验室的水平不等,导致数据间无法互相比较.笔者会同美国木洞海洋研究所的P.Brewer及法国巴黎第六大学的A.Poisson进行了互校工作.初步互校结果显示IAPSO标准海水可用作TA的标准,3个实验室平均值之差距仅为1.8μmol/kg(0.08%).TCO₂及pH之互校结果则较不理想,除实验误差外,标准海水内的有机质分解,也可能导致TCO₂及pH的改变. 进一步互校由全球9个国家和地区的12个实验室参加,结果很不理想.建议日后由二三位公认可靠的专家进行小规模互校,找出出现差异的原因后,再制作标准溶液供不同国家和地区使用.     

咸淡水过渡带化学过程的试验研究

通过不同比例的咸淡水混合作用及水岩作用的室内模拟实验,对咸淡水过渡带的水文地球化学作用进行了研究。在咸淡水混合作用的过程中,海水与淡水的混合是以机械混合为基础的复杂的化学过程,混合液的总碱度和pH值均显著上升,而电导率明显下降,方解石和石膏的饱和指数均明显增大,而Pco2降低。在水岩作用的过程中,混合液的pH值、总碱度和电导率均显著上升,石膏的饱和指数由～1．06～-0．71升高至-0．86～-0．50,石膏发生溶解;方解石的饱和指数由0．69～1．07降至0.00-0．10,方解石发生沉淀．最后接近平衡状态。     

碱度长期胁迫对花鲈肾组织转录组的影响

为了解花鲈(Lateolabrax maculatus)的耐碱机制,本研究探讨了碱度长期胁迫对花鲈肾组织转录组的影响。研究设计了3个碳酸盐碱度梯度(0、15和30 mmol/L),基于Illumina Novaseq 6000高通量测序平台进行了花鲈肾组织转录组测序并进行了生物信息学分析。研究表明,con组(0 mmol/L)、AW15组(15 mmol/L)和AW30组(30 mmol/L)分别获得了163 197 546、145 296 406和141 892 236条Clean reads。与con组相比,AW15组和AW30组分别有142和3 103个差异表达基因上调,104和2 235个差异表达基因下调。随机选取9条差异表达基因进行实时荧光定量PCR验证,结果与转录组测序一致,表明本研究中RNA-seq结果具有较高的可靠性。GO富集分析发现,差异基因显著富集在气体运输、GTP酶活性的正调控和水解酶活性的正调控等方面;KEGG通路富集分析表明,差异基因显著富集在细胞周期、DNA复制和癌症中的蛋白多糖等方面。本研究发现了49个持续变化基因(fyn、ceacam和acsl等),这些...     

海上油气田水质分析新方法

由于海上油气田目前应用行业标准在现场水质检测时存在缺陷,特别是CO3^2-和HCO3-等离子的特殊易变性,因此开发出一套适合于现场的快速、准确全新水质分析方法具有重要意义。上海采油技术服务公司首次利用CO2等离子选择性电极对海上油田水中易变离子用仪器直接测定,得到了现场验证。该离子进行测定并与传统的酸碱滴定方法进行对比发现,CO2电极法测定与酸碱滴定法测定结果基本一致,且方法更简便,更适合现场测定。     

Spatial and temporal variations in pH and total alkalinity at the beginning of the rainy season in the Changjiang Estuary, China

The results of field observation carried out in May 2003 were used to examine pH and total alkalinity behaviors in the Changjiang Estuary. It was showed that pH and total alkalinity took on clear spatial variations in values with the minima in the low salinity region. Like salinity, transect distributions of pH and total alkalinity （TA） in a downriver direction had a sharp gradient each. These gradients appeared in such a sequence that the TA gradient was earlier than salinity and pH gradients, and the salinity gradient was earlier than the pH gradient. These distribution characteristics seemed to be strongly influenced by the mixing process of freshwater and seawater, for both pH and total alkalinity had significant linear relationships with salinity and temperature. For pH, phytoplankton activities also had a significant impact upon its spatial distribution. During a period of 48 h, pH and total alkalinity changed within wide ranges for every layer of the two anchor stations, namely, Stas 13 and 20, which were located at the mixed water mass and seawater mass, respectively. For both Stas 13 and 20, pH and TA fluctuation of every layer could be very wide during a 4 h period. As a whole, the data of the two anchor stations showed that neither variations in salinity and temperature nor phytoplankton activities were the main factors strongly influencing the total alkalinity temporal variability on a small time scale. The data of Sta. 20 implied that both salinity variation and phytoplankton activities had a significant influence on pH temporal variability, but the same conclusion could not be drawn from the data of Sta. 13.     

Removal of K^＋, Na^＋, Ca^2＋, and M^g2＋ from saline-alkaline water using the microalga Scenedesmus obliquus

The capability ofScenedesmus obliquus to remove cations （K^＋, Na^＋, Ca^2＋, Mg^2＋） from saline- alkaline water was investigated at different salinities （0, 5, 10, 15, 20, 25） and carbonate alkalinities （0, 5, 10, 15, 20, 25, 30, 35 mmol/L）. K^＋, Na^＋, Ca^2＋, and Mg^2＋ in saline-alkaline water were efficiently removed by S. obliquus. The maximum removal of the cations （29.37 mg for K^＋, 185.85 mg for Na^＋, 23.07 mg for Ca^2＋, 66.14 mg for Mg^2＋） occurred at salinity 25. The maximum removal of K^＋ （2.28 mg）, Na＋ （6.62 mg）, Ca^2＋ （1.01 mg）, and Mg2＋ （0.62 mg） occurred at carbonate alkalinities of 25 mmol/L for K＊, 35 mmol/L for Na＋, 20 mmol/L for Ca2＋, and 25 mmol/L for Mf＋, respectively. Under a salinity stress, the concentration of Na＇ in S. obliquus increased significantly, while that of K~ decreased significantly. The concentrations of Ca^2＋ and Mg2＋ decreased as well. The ratios of K＋/Na~, Ca2＋/Na^＋, and Mg^2＋/Na^＋ were significantly lower in all salinity treatments than those of the control. Under alkaline stress, the concentrations of Nan and K＋ in S. obliquus decreased significantly and the ratios of K^＋/Na^＋, Ca2＋/Na^＋, and Mg^2＋/Na^＋ were significantly higher in all treatments than in the control. Moreover, the concentrations of Ca2＋ and Mg2＋ in S. obliquus at alkalinities of 5-10 mmol/L were significantly higher than those of the other treatments. The removal of Na＋ by S. obliquus mainly occurs through biosorption, and Mg^2＋ and Ca^2 ＋ were removed through both biosorption and bioaccumulation.     

南沙海区微表层的研究——pH、碱度、密度和表面张力的测定

对南沙海区部分站位微表层和次表层的ｐＨ、碱度、密度和表面张力进行了测定。结果表明：微表层的表面张力低于次表层的表面张力,并且表面张力与溶解有机碳（ＤＯＣ）相关;微表层的ｐＨ低于次表层的ｐＨ,并探讨了其原因;微表层的碱度和密度一般高于次表层,同时对其原因进行了探讨。