牙鲆幼鱼越冬饲养期环境因子研究     

陆赛英  陈士群  毛兴华 《海洋科学进展》1999,(2)

本文重点研究牙鲆鱼越冬饲养期间所需的适宜温度和盐度条件,以及牙鲆对酸碱度的耐受力。研究结果表明温度是影响牙鲆在越冬期标准代谢的主要环境因子。７～１４．５℃是越冬期牙鲆能量代谢变动最低的温度区间,也是最适宜的温度范围。盐度也是影响牙鲆越冬期的环境因子,在７～１４．５℃的温度条件下,其盐度阈值下限为２０;４０仍属适宜盐度。牙鲆的耐酸力比耐碱性强,９６ｈ和４８ｈ致死的ｐＨ值分别为４．４５和４．２０,当ｐＨ值为９．３０时,牙鲆１６ｈ死亡。  相似文献   

黄河口总碱度保守与非保守行为探讨   总被引：6，自引：1，他引：5  

王晓亮  张龙军  苏征  李岩  张向上  高会旺 《中国海洋大学学报(自然科学版)》2005,35(6):1063-1067,1062

为了阐明黄河口TAlk（总碱度）的行为特征及主要影响因素,根据2004年4月黄河口TAlk实测数据,结合其它化学要素的同步观测资料对其进行了初步探讨.研究结果表明： 黄河口水体在S〈24的区域范围内TAlk呈现出非保守行为,其中 S〈5时TAlk非保守表现为净TAlk的“亏损”, 即水体TAlk低于理论混合TAlk,是由于水体中DIC的沉淀作用引起;在盐度为8～24之间,TAlk非保守表现为净TAlk的“增加”,即水体TAlk高于理论混合TAlk,主要是由于水体中颗粒碳酸盐溶解引起;水体中的CO2参与了颗粒碳酸盐的溶解,并且很可能是影响水体中碳酸盐溶解的主要因素.  相似文献   

基于灰色关联度的地下水化学成分分析     

邓丽娟  刘亮 《地下水》2009,31(2):17-19

依据新疆某水库周边耕地地下水水样化验数据,应用灰色关联分析与相关分析相结合的方法,分析了地下水主要成分与总硬度、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Ca2+影响,水中HCO3-含量与总碱度关系密切,电导率主要受Mg2+影响,Na+、K+和与Mg2+对矿化度有较大影响.通过相关分析,发现它们之间相关性极为显著.  相似文献   

The status of the passive treatment systems for acid mine drainage in South Korea     

Sangwoo Ji  Sunjoon Kim  Juin Ko 《Environmental Geology》2008,55(6):1181-1194

This study was performed to investigate the operating status, evaluate the problems, and discuss possible improvement methods of passive treatment systems for acid mine drainage (AMD) in South Korea. Thirty-five passive treatment systems in 29 mines have been constructed from 1996 to 2002 using successive alkalinity producing systems (SAPS) as the main treatment process. We investigated 29 systems (two for metal mines), 19 of which revealed various problems. Overflows of drainage from SAPS, wetland, or oxidation ponds were caused by the flow rate exceeding the capacities of the facilities or by the reduced permeability of the organic substance layer. Leakages occurred at various parts of the systems. In some cases, clogged and broken pipes at the mouths of the mine adits made the whole system unusable. Some systems showed very low efficiencies without apparent leakage or overflow. Even though the systems showed fairly good efficiencies in metal removal ratios (mainly iron) and pH control; sulfate removal rates were very poor except in three systems, which may indicate very poor sulfate reductions with sulfate reducing bacteria (SRB) as a means.  相似文献   

The saturation of calcite and aragonite in the Arctic Ocean   总被引：1，自引：0，他引：1  

Sara Jutterstrm  Leif G. Anderson 《Marine Chemistry》2005,94(1-4):101

We report on the chemical saturation of CaCO₃ in the waters of the Arctic Ocean calculated from total alkalinity (A_T) and total dissolved inorganic carbon (C_T). Data based on four different expeditions are presented: International Arctic Ocean Expedition (IAOE-91), Arctic Ocean Section 94 (AOS94), Polarstern Arctic '96 expedition (ACSYS 96), and Joint Ocean Ice Study 97 (JOIS 97). The results show a lysocline at around 3500 m for aragonite and that most of the Arctic Ocean sea floor lies above the lysocline for calcite. The only anomaly is the low degree of saturation at the shelf break depth in the Canadian Basin seen in the sections of the AOS94 and JOIS 97 cruises, correlated with nutrient maxima and very low O₂ concentration, suggesting decomposition of organic matter. The insignificant variability in degree of saturation between the deep waters of the different basins in the Arctic Ocean indicates a very low sedimentation/remineralisation of organic soft matter.  相似文献   

台湾地区湖库水酸化之研究     

王冰洁  陈镇东 《海洋湖沼通报》1995,(2):12-23

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。  相似文献   

The reliability of the thermodynamic constants for the dissociation of carbonic acid in seawater     

Kitack Lee  Frank J. Millero  Douglas M. Campbell 《Marine Chemistry》1996,55(3-4)

Laboratory measurements of all four CO₂ parameters [f_CO2 ( = fugacity of CO₂), pH, TCO₂ ( = total dissolved inorganic carbon), and TA ( = total alkalinity)] were made on the same sample of Gulf Stream seawater (S = 35) as a function of temperature (5–35 °C) and the ratio of TA/TCO₂ (X) (1.0–1.2). Overall the measurements were consistent to ±8 μ atm in f_CO2, ± 0.004 in pH, ± 3 μ mol kg⁻¹ in TCO₂, and ± 3 μ mol kg⁻¹ in TA with the thermodynamic constants of Goyet and Poisson (1989), Roy et al. (1993), and Millero (1995). Deviations between the measured pH, TCO₂, TA and those calculated from various input combinations increase with increasing X when the same constants are used. This trend in the deviations indicates that the uncertainties in pK₂ become important with increasing X (surface waters), but are negligible for samples with the lower X (deep waters). This trend is < 5 μ mol kg⁻¹ when the pK₂ values of Lee and Millero (1995) are used.The overall probable error of the calculated f_CO2 due to uncertainties in the accuracy of the parameters (pH, TCO₂, TA, pK₀, pk₁, and pK₂) is ± 1.2%, which is similar to the differences between the measured values and those calculated using the thermodynamic constants of Millero (1995).The calculated values of pK₁, (from f_CO2-TCO₂-TA) agree to within ± 0.004 compared to the results of Dickson and Millero (1987), Goyet and Poisson (1989), Roy et al. (1993), and Millero (1995) over the same experimental conditions. The calculated values of pK₂ (from pH-TCO₂-TA) are in good agreement (± 0.004) with the results of Lee and Millero (1995) and also in reasonable agreement (± 0.008) with the results of Goyet and Poisson (1989), Roy et al. (1993), and Millero (1995). The salinity dependence of our derived values of pK₁ and pK₂, (S = 35) can be estimated using the equations determined by Millero (1995).  相似文献   

Diatom-based water chemistry reconstructions from northern Sweden: a comparison of reconstruction techniques   总被引：6，自引：0，他引：6  

T. Korsman  H. J. B. Birks 《Journal of Paleolimnology》1996,15(1):65-77

The diatom composition in surface sediments from 119 northern Swedish lakes was studied to examine the relationship with lake-water pH, alkalinity, and colour. Diatom-based predictive models, using weighted-averaging (WA) regression and calibration, partial least squares (PLS) regression and calibration, and weighted-averaging partial least squares (WA-PLS) regression and calibration, were developed for inferences of water chemistry conditions. The non-linear response between the diatom assemblages and pH and alkalinity was best modelled by weighted-averaging methods. The lowest prediction error for pH was obtained using weighted averaging, with or without tolerance downweighting. For alkalinity there was still some information in the residual structure after extracting the first weighted-averaging component, which resulted in a slight improvement of predictions when using a two component WA-PLS model. The best colour predictions were obtained using a two component PLS model. Principal component analysis (PCA) of the prediction errors, with some characteristics of the training set included as passive variables, was performed to compare the results for the different alkalinity predictive models. The results indicate that calibration techniques utilizing more than one component (PLS and WA-PLS) can improve the predictions for lakes with diatom taxa that have broad tolerances. Furthermore, we show that WA-PLS performs best compared with the other techniques for those lakes that have a high relative abundance of the most dominant taxa and a corresponding low sample heterogeneity.  相似文献   

Acidity of twelve northern New England (U.S.A.) lakes in recent centuries     

Ronald B. Davis  Dennis S. Anderson  Stephen A. Norton  Mark C. Whiting 《Journal of Paleolimnology》1994,12(2):103-154

Studies of sediment cores from 12 acidic lakes in granitic, forested and uninhabited catchments in northern New England, U.S.A. produced diatom-inferred pH (IpH) 5.2 to 5.8 and alkalinity (Ialk) –12 to 31 µeq l^–1, with slowly declining values at some lakes, for one to four centuries prior to logging. Increases of IpH (0.05 to 0.60) and Ialk (5 to 40 µeq l^–1) correlate with logging in the catchments in the early-1800s to early-1900s. Recovery to pre-logging IpH and Ialk correlates with forest succession toward conifers, and is completed in the late-1800s to mid-1900s. Beginning at 1915–1920 (4 lakes), 1930–1950 (4 lakes) and 1965–1970 (4 lakes), IpH and Ialk start decreasing below pre-logging values due to atmospheric acidic deposition, leading to respective total decreases of 0.10 to 0.45 (X=0.25) and 5 to 25 µeq l^–1 (X=15). Inputs of anthropogenic Pb, Zn, V, polycyclic aromatic hydrocarbons, and soot from the atmosphere are first detectable in early- to late-1800s sediment, and Cu in late-1800s sediment, increase rapidly in the late-1800s to mid-1900s, and level off or decrease since the 1960s — partly due to emission controls. Decreasing Ca, Mn, and possibly Zn relative to other metals and normalized to organic content, and increasing flux of Fe to the lakes, indicate soil and water acidification after 1900.This is the fourteenth of a series of papers to be published by this journal which is a contribution of the Paleoecological Investigation of Recent Lake Acidification (PIRLA) project. Drs. D. F. Charles and D. R. Whitehead are guest editors for this series.  相似文献   

Carbon dioxide dynamics in rivers and coastal waters of the “big island” of Hawaii,USA, during baseline and heavy rain conditions     

François S. Paquay  Fred T. Mackenzie  Alberto V. Borges 《Aquatic Geochemistry》2007,13(1):1-18

The distributions of the partial pressure of carbon dioxide (pCO₂) and total alkalinity (TA) were examined for a 6-month period in the Wailuku and Wailoa rivers and coastal waters of Hilo Bay on the west coast of the Island of Hawaii, USA. Main results for the largest and turbulent Wailuku River show in the watershed an oversaturation in CO₂ with respect to atmospheric equilibrium and a CO₂ undersaturation in the estuary. In the Wailoa river-estuary system, extremely high pCO₂ values ranging from 1500 to 10500 ppm were measured with significant shifts in pCO₂ from drought to flood period. In the two rivers, water residence time, groundwater inputs and occasional flood events are the predominant drivers of the spatial and temporal patterns in the distribution of pCO₂. In Hilo Bay, CO₂ oversaturation dominates and the bay was a source of CO₂ to the atmosphere during the study period. TA is conservative along the salinity gradient, indicating calcification in the bay is not a significant source of CO₂ to the atmosphere.  相似文献