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21.
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.  相似文献   
22.
In this study, we examined the relationship between the low salinity water in the shelf region of the southern Okhotsk Sea which was seasonally sampled (0–200 m), and fluxes of low salinity water from Aniva Bay. To express the source of freshwater mixing in the surface layer, we applied normalized total alkalinity (NTA) and stable isotopes of seawater as chemical tracers. NTA-S diagrams indicate that NTA of low salinity water in the upper 30 m layer just off the Soya Warm Current is clearly higher than in the far offshore region in summer and autumn. Using NTA-S regression lines, we could deduce that the low salinity and high NTA water in the upper layer originates from Aniva Bay. For convenience, we defined this water as the Aniva Surface Water (ASW) with values S < 32, NTA > 2450 μmol kg−1. Formation and transport processes of ASW are discussed using historical data. The interaction between the maximum core of high NTA water on the bottom slope of eastern Aniva Bay and an anticyclonic eddy at the mouth of Aniva Bay are concluded to control ASW formation. Upwelling of the Cold Water Belt water at the tip of Cape Krillion is considered to cause ASW outflow from Aniva Bay.  相似文献   
23.
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.  相似文献   
24.
依据新疆博州地区20处地下水水样的水质化验数据,应用关联分析与相关分析相结合的分析方法,分析了地下水样中几种成分与总硬度、总碱度、电导率及矿化度4个指标之间的关系。结果表明,总硬度变化主要受Mg2+影响,水中HCO3-含量与总碱度关系密切,电导率主要受SO42-影响,SO42-与Cl-对矿化度有较大影响。通过相关分析,发现它们之间线性相关性较好。  相似文献   
25.
利用盐碱地区氯化物型地下水进行了鲢鱼幼鱼(L=5.4~8.2cm)对盐度(pH=8.60±0.18)、碱度(pH=8.74±0.34)及盐碱混合的急性毒性试验。研究结果表明:鲢鱼幼鱼对盐度的24、48、72和96h的半致死浓度(LC50)分别为:11.2,9.0,8.6和8.2g·L-1;对碱度的相应LC50值分别为51.4、27.1、23.7和15.7mmol·L-1。盐碱混合的正交试验表明盐度和碱度在致毒过程中作用显著;24hLC50碱度(Alk,mmol·L-1)及盐度(S,g·L-1)的关系为:Alk=34.17-1.78S。  相似文献   
26.
This paper evaluates whether a thermodynamic ocean-carbon model can be used to predict the monthly mean global fields of the surface-water partial pressure of CO2 (pCO2SEA) from sea surface salinity (SSS), temperature (SST), and/or nitrate (NO3) concentration using previously published regional total inorganic carbon (CT) and total alkalinity (AT) algorithms. The obtained pCO2SEA values and their amplitudes of seasonal variability are in good agreement with multi-year observations undertaken at the sites of the Bermuda Atlantic Timeseries Study (BATS) (31°50’N, 60°10’W) and the Hawaiian Ocean Time-series (HOT) (22°45’N, 158°00’W). By contrast, the empirical models predicted CT less accurately at the Kyodo western North Pacific Ocean Time-series (KNOT) site (44°N, 155°E) than at the BATS and HOT sites, resulting in greater uncertainties in pCO2SEA predictions. Our analysis indicates that the previously published empirical CT and AT models provide reasonable predictions of seasonal variations in surface-water pCO2SEA within the (sub) tropical oceans based on changes in SSS and SST; however, in high-latitude oceans where ocean biology affects CT to a significant degree, improved CT algorithms are required to capture the full biological effect on CT with greater accuracy and in turn improve the accuracy of predictions of pCO2SEA.  相似文献   
27.
一种新型的海水COD在线测量仪已经研制出来,其采用了碱性高锰酸钾法和流动注射分析技术,仪器的测量结果与标准方法有很好的一致性,它们的相关系数超过0.98。  相似文献   
28.
自动电位滴定仪高效高精度测定海水碱度值   总被引:1,自引:0,他引:1       下载免费PDF全文
为研究海洋碳循环和海洋碳酸盐系统,需要测定样品的碳酸盐碱度。利用电位滴定仪(万通~(?)798MPT Titrino)配合软件tiamol.1检测了海水总碱度。根据碳酸盐解离常数计算出了海水碳酸盐碱度,相时标准偏差低于0.1%(±2μmol/kg),单个样品用量约25 mL,检测时间约9 min。实验结果表明,用自动电位滴定仪测定海水总碱度速度快,精度高,方法可行。  相似文献   
29.
白令海BR断面海-气CO2通量及其参数特征   总被引:1,自引:0,他引:1  
通过对2008年夏季白令海大气和海水pCO2连续观测资料,结合BR断面上站位水体垂直采样测量,对白令海不同海区pCO2的分布特征及其与理化参数的关系进行了初步研究,结果表明,将白令海划分为4个具有不同CO2吸收能力的海区,其中陆坡流区碳通量高达-18.72 mmol/(m2·d),是海盆北区的近2倍,比海盆南区高一个量...  相似文献   
30.
Total carbon, nitrogen, and phosphate parameters were studied for the first time in the groundwater in the Silifke coastal plain, which is a RAMSAR site in Turkey. Seasonal variations of these parameters in the plain were examined based on groundwater data collected from 21 wells during the winter, spring, summer, and fall seasons. Total dissolved organic carbon (DOC), inorganic carbon (DIC), inorganic phosphate (DIP), inorganic nitrogen (DIN), and total alkalinity (TAlk) average values in the groundwater were low in all seasons (<2.2 mg/L for DOC; <54 mg/L for DIC; <0.06 mg/L for DIP; <1.5 mg/L for DIN; <232 mg/L for TAlk). The results showed a strong relationship between DIC and as expected. The results indicate that the content of these parameters in the groundwater of Silifke coastal plain pose no or little risk at present. However, computed Langelier Saturation Index (LSI) values indicated that the groundwater has a tendency to form scale and CaCO3 precipitation may occur.  相似文献   
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