白令海BR断面海-气CO2通量及其参数特征

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...     

Dissolved Nutrient Distributions in Groundwater in the Mediterranean Coastal Plains – the Case of Silifke,Turkey

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.     

Topographic,pedologic and climatic interactions influencing streamflow generation at multiple catchment scales

Dominant flow pathways (DFPs) in mesoscale watersheds are poorly characterized and understood. Here, we make use of a conservative tracer (Gran alkalinity) and detailed information about climatic conditions and physical properties to examine how temporally and spatially variable factors interact to determine DFPs in 12 catchments draining areas from 3.4 to 1829.5 km² (Cairngorms, Scotland). After end‐member mixing was applied to discriminate between near surface and deep groundwater flow pathways, variation partitioning, canonical redundancy analyses and regression models were used to resolve: (i) What is the temporal variability of DFPs in each catchment?; (ii) How do DFPs change across spatial scales and what factors control the differences in hydrological responses?; and (iii) Can a conceptual model be developed to explain the spatiotemporal variability of DFPs as a function of climatic, topographic and soil characteristics? Overall, catchment characteristics were only useful to explain the temporal variability of DFPs but not their spatial variation across scale. The temporal variability of DFPs was influenced most by prevailing hydroclimatic conditions and secondarily soil drainability. The predictability of active DFPs was better in catchments with soils supporting fast runoff generation on the basis of factors such as the cumulative precipitation from the seven previous days, mean daily air temperature and the fractional area covered by Rankers. The best regression model R² was 0.54, thus suggesting that the catchments’ internal complexity was not fully captured by the factors included in the analysis. Nevertheless, this study highlights the utility of combining tracer studies with digital landscape analysis and multivariate statistical techniques to gain insights into the temporal (climatic) and spatial (topographic and pedologic) controls on DFPs. Copyright © 2011 John Wiley & Sons, Ltd.     

西北冰洋总碱度与溶解无机碳的分布

2008年7～9月,中国进行了第三次北极科学考察。本研究即利用此次宝贵的科学考察机会,在西北冰洋现场采集大量的海水样品,进行二氧化碳体系（主要包括总碱度(TA),和溶解无机碳(DIC)等）研究。得到了西北冰洋二氧化碳体系参数的分布,并对其控制因素进行了讨论。夏季西北冰洋表层海水总碱度（TA）、盐度归一化总碱度（nTA,nTA =TA*35/S）、溶解无机碳（DIC）和盐度标准化溶解无机碳（nDIC,nDIC=DIC*35/S）的范围分别为1757～2229μmol kg-1,2383～2722μmol kg-1,1681～2034μmol kg-1,2119～2600μmol kg-1。由于受到河水和海冰融化水的稀释,表层DIC和TA的浓度都比较低。78°N以南西北冰洋上层水柱中TA与盐度有良好的正相关关系,比较保守,在盐度大于30时,主要是海水端元与河水端元混合,在盐度小于30时主要是海水端元与海冰融化水端元的混合。在楚科奇海,DIC分布主要受到有机质生产或降解的主控,而加拿大海盆无冰区混合层DIC分布的主控因素是海水与海冰融化水的保守混合。     

滴定水样总碱度中终点的确定和指示剂的选择

本文讨论了水样中总碱度含量与滴定等当点的变化关系和甲基橙在不同pH值下颜色的变化情况。试验了可用于滴定水样总碱度的常见的10种酸碱指示剂。结果表明,用溴甲酚绿指示终点优越,颜色突跃清楚。     

High-resolution varve studies in Baldeggersee (Switzerland): Project overview and limnological background data

This introduction to a series of high-resolution varve studies in Baldeggersee provides both an overview of the different subprojects as well as background information on relevant limnological trends. The project was based on a new method of in-situ freezing of unconsolidated surficial sediments in deep lakes. With this freeze-core technique a detailed, high-resolution stratigraphy of the varved sediments at the deepest point of Baldeggersee has been established for the period of 1885–1993. Annual and seasonal sediment samples were analyzed. Concentrations of redox active metals in sediments were calibrated as proxy indicators for the reconstruction of hypolimnetic oxygen conditions. Particle size analysis and varve measurements were used to discriminate between the influence of nutrients and climate on sediment formation and accumulation. Baldeggersee is an ideal system for calibrating indicators of deep-water oxygen concentrations because it underwent dramatic changes in nutrient loading and redox conditions during this century. The hypolimnion has been seasonally anoxic for the last 100 years and phosphorus content decreased by a factor of five in the last 20 years. Meromixis was observed between 1960 and 1980. Since 1983 the deep water has been artificially oxygenated. This well documented change in deep-water oxygen concentration represents a unique whole-lake experiment that can be used to analyze the geochemical response of the sediments.     

氯化物水型盐碱池塘浮游植物叶绿素a的研究

于 1997年 4月至 1998年 9月对山东省高青赵店渔场 ( 37°17′N,117°55′E)的盐碱池塘叶绿素进行了调查研究 .结果表明 ,盐碱池塘叶绿素总量平均为 115.12μg· L-1,叶绿素 a平均含量为 73.90μg· L-1,占叶绿素总量的 61.76% ,叶绿素 b和叶绿素 c分别占总量的 12 .97%和2 5.2 7% .叶绿素 a含量的季节变动较大 ,有明显盛夏和初秋高峰期 .无鱼对照池的叶绿素 a比养鱼池塘低得多 .叶绿素 a的昼夜变化与垂直分布变化较大 ,但不遵循同一模式 .盐碱池塘叶绿素 a含量与浮游植物生物量、水温、总氮、总磷和硅酸盐显著正相关 ,与透明度显著负相关 ,而与盐度、碱度、p H、硬度、电导率均无规律性联系     

Partial Pressure of Carbon Dioxide in Coral Reef Lagoon Waters: Comparative Study of Atolls and Barrier Reefs in the Indo-Pacific Oceans

Factors controlling the CO₂ system parameters, including the partial pressure of CO₂ (PCO₂) in coral reef waters, were investigated in three mid-oceanic reefs of the Indo-Pacific region. Surface water PCO₂ in the lagoons of Majuro Atoll and Palau barrier reef in the Pacific were 25 µatm and 48 µatm higher than those of the offshore waters, respectively, while South Male Atoll lagoon of the Maldives in the Indian Ocean exhibited relatively small difference in PCO₂ compared to the offshore water. Observations from Majuro Atoll and Palau barrier reef are consistent with the view that calcium carbonate production predominates in coral reefs. On the other hand, results from South Male Atoll can be attributed to the thorough flushing of the lagoon, which is connected to the open ocean by numerous deep channels. The offshore-lagoon PCO₂ difference depends on system-level net organic-to-inorganic carbon production ratio while reef topography, especially residence time of the lagoon, has a secondary effect on the magnitude of the offshore-lagoon difference. A potential for releasing CO₂ might be more evident in an enclosed atoll where the reef water has a longer residence time. Oceanic atoll and barrier reef lagoons, which are in the terminal stage of evolutionary history of oceanic volcanic islands, have the potential to release CO₂ to the atmosphere.     

Prediction of surface ocean pCO2 from observations of salinity, temperature and nitrate: The empirical model perspective

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 (pCO_2SEA) from sea surface salinity (SSS), temperature (SST), and/or nitrate (NO₃) concentration using previously published regional total inorganic carbon (C_T) and total alkalinity (A_T) algorithms. The obtained pCO_2SEA 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 C_T 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 pCO_2SEA predictions. Our analysis indicates that the previously published empirical C_T and A_T models provide reasonable predictions of seasonal variations in surface-water pCO_2SEA within the (sub) tropical oceans based on changes in SSS and SST; however, in high-latitude oceans where ocean biology affects C_T to a significant degree, improved C_T algorithms are required to capture the full biological effect on C_T with greater accuracy and in turn improve the accuracy of predictions of pCO_2SEA.     

夏季西北冰洋表层淡水分布的总碱度示踪研究

利用中国第三次北极科学考察在西北冰洋所进行的海水总碱度的测量,通过海水、海冰融化水以及河源淡水三个端元总碱度特征的显著差异计算西北冰洋夏季表层海水中淡水所占的比例。研究表明,西北冰洋海冰融化水所占比例最大区域在加拿大海盆区75°N附近,这是冰缘带位置,往北向高纬度的冰密集中逐渐增加。而河源淡水的组份则与北冰洋的环流密切相关,并且在西北冰洋水体中逐渐累积。