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1.
杭州湾海水中的硼和锶的研究   总被引:1,自引:0,他引:1  
采用作者研究的OP- 乳化剂增敏姜黄素分光光度法测定海水中的溶解硼,用ICP- AES法测定海水中的溶解锶。发现在杭州湾海水盐度5 .563 ~26 .397 ,氯度3.022 ~14 .582 范围内,硼浓度为0 .68 ~3.24mg/kg,锶浓度为1 .29~5 .88mg/kg,B(mg/kg)/Cl 比值为0 .219~0 .245,平均值为0.232±0 .007 ,Sr(mg/kg)/Cl 比值范围为0.398 ~0.440 ,平均值为0.417 ±0.011 。结果表明,湾内海水中的硼和锶浓度与海水盐度或氯度均有很好的线性正相关关系,丰水期与枯水期水样数据关系相同,不因采水时间不同而变化。实验数据统计回归线与理论稀释线比较后表明,湾内海水中锶与硼均具有良好保守性质;湾内海水中的硼和锶主要来自湾外潮汐输入。湾东北沿岸海水高的B/Cl比值,暗示着此处有含硼工业废水排入湾内,认为B/Cl 比可作为近岸河口海水硼污染的一种指标。杭州湾海水中未检测到硼有机络合物。  相似文献   

2.
采用作者研究的OP- 乳化剂增敏姜黄素分光光度法测定海水中的溶解硼,用ICP- AES法测海水中的硼和锶。发现在珠江口海水盐度2.686 ~25 .722 ,氯度1 .440 ~14 .136 为0.215 ~0 .229mg·kg- 1 ,平均值为0 .224±0 .005mg·kg- 1 mg·kg- 17 .64 ,Sr(mg·kg- 1)/Cl 比值为0.380 ~0 .663,平均值为0 .404 ±0 .016 ,两者皆在大洋海水自然变动范围之内。珠江口海水中的硼和锶浓度与海水盐度或氯度均有很好的线性关系。珠江口外南海海水盐度32 .923 ~33.446, 氯度18 .241 ~18.558 ,B浓度为4 .02 ~4 .24mg·kg- 1 ,Sr 浓度为7.64 ~7 .70mg·kg- 1 。珠江口海水实验数据统计回归线与理论释线比较后表明,珠江口海水中硼与锶均具有良好的保守性质,珠江口海水中的硼和锶主要来自湾外海海水潮汐输入。  相似文献   

3.
提出用氧瓶燃烧-光度法来测定有机物中硫含量的定量分析方法,在低硫酸根浓度范围内(4~25mg/l),在浓碱条件下MTB(甲基百里酚蓝)的吸光度与硫酸根浓度在460nm波长处呈正相关,而在600nm(或610nm)处Ba-MTB络合物的吸光度与硫酸根浓度呈负相关。该方法标准偏差低于0.5mg,/l.变异系数低于3%,回收率为95-107%。  相似文献   

4.
实验于1996年5月~9月对3种规格养殖中国对虾在不同条件下的耗氧率和排氨率进行了测定。结果表明,温度、体重、盐度和摄食状态对其代谢有显著影响。耗氧率(QO)和排氨率(QN)与温度正相关,lnQO=0.058T-2.894;lnQN=0.076T+1.116;而与体重呈负相关,QO=0.515W-0.126;QN=25.05W-0.199。在盐度5~35范围内,中国对虾(3.025g±0.088g)的耗氧率和排氨率在盐度28时最小。中国对虾(3.13g±0.072g)摄食沙蚕和配合饲料,在饱食状态下耗氧率比饥饿状态下分别提高了83.9%和29.3%,排泄率增加了113.8%和93.6%,表明摄食时蛋白质代谢增加显著。  相似文献   

5.
虾病暴发前虾池中一些环境因子的变化   总被引:2,自引:1,他引:1  
实验研究1994年5~8月即墨金口养殖场虾病发生前,养虾池中叶绿素a总量、去镁叶绿素含量、不同粒径浮游植物叶绿素a含量以及营养盐的变化。结果表明:在整个调查期间两个养虾池中叶绿素a含量逐月减小,分别从49.98mg/m3和25.54mg/m3降至1.50mg/m3和3.30mg/m3,去镁叶绿素含量呈上升趋势。微型(2~20μm)的浮游植物叶绿素a含量最大,分别为74.3%和68.4%,超微型(2~0.45μm)分别为20.4%和27.5%,小型(>20μm)的叶绿素a含量最小,分别为5.5%和4.2%。所调查虾池中无机磷含量均超过富营养化阈限,无机氮含量接近富营养化阈限。  相似文献   

6.
海带中褐藻酸盐组成的研究   总被引:5,自引:1,他引:5       下载免费PDF全文
将海带(Laminaria japonica)进行蒸馏水沥洗和晾干处理,定量测定海带中褐藻酸及其结合的金属元素的含量。结果表明:海带中的褐藻酸是以多种褐藻酸盐的形式存在,海带中的褐藻酸盐主要是由褐藻酸镁、钾、钠、钙、锂、硼和锶等组成(占褐藻酸盐总量的96.96%)。本文提出了海带中各种褐藻酸盐的含量以及海带对海水中各种金属元素的富集倍数。  相似文献   

7.
鳗饲料添加螺旋藻粉的养殖效果   总被引:1,自引:0,他引:1  
陈启发 《台湾海峡》1998,17(A12):70-74
本文报道了用Spirulina platensis粉添加于“厦清”、“大昌”牌养鳗饲料中喂养日本鳗苗的试验。结果表明,添加该藻粉2.0%喂养僵鳗30d,其饲料系数比对照组均下降,降幅为21.2% ̄53.7%,鳗增重倍数提高0.029 ̄0.171;添加该藻粉2.5% ̄2.0%喂养正常幼鳗118d,其饲料系数分别降低0.074 ̄0.234和0.024 ̄0.181,且鳗个体均匀,规格较大。  相似文献   

8.
用箱式采样器采集了美国佛罗里达州东海岸奥·伽利河口的沉积物柱状样,分析了间隙水的氯度、pH、Eh、5项植物营养盐、碱度、硫酸根、硫离子和锰.Eh小于零,硝酸根在整个沉积物中被耗尽,硫酸根在9cm处耗尽,硫离子浓度较高,说明整个沉积物处在还原性环境中;营养盐的再生过程进行的很激烈,离子活度积的计算结果说明,硫离子在控制间隙水中金属离子浓度方面起着重要的作用.  相似文献   

9.
首次实验研究胶州湾海水中的硼,胶州湾表层海水中硼的浓度为3.24 ~3 .87mgkg- 1 ,B/Ci比值为0 .181 ~0.215 ,平均值为0 .204 ±.0 .009 。B/S比值为0 .100~0 .120,平均值为0 .113 ±0.005。湾内硼的分布,低值区在李村河口沧口湾附近,而在湾的东西两侧、东北角及湾口区域海水中硼浓度则较高。湾内海水中的硼主要靠湾外海潮输入。因湾内无常年径流流入,盐度分布变化小,硼浓度随盐度及氯度变化不明显。相对于北黄海水,胶州湾海水硼平均迁出量8.65% ,胶州湾海水中的硼表现为非保守性质。  相似文献   

10.
黄金龙  周燕 《台湾海峡》1992,11(2):146-154
本工作测定了有效离子强度I_=0.5277mol/L和25℃下碳酸在若干人工海水介质中的表现离解常数,计算了碳酸根和碳酸氢根与钾、钠、镁、钙的缔合常数,讨论了包括氯离子缔合和未考虑氯离子缔合的海水化学模型,还通过试验证实了钾与碳酸根、碳酸氢根的缔合是不可忽视的,其缔合常数与钠的缔合常数相近,从而扩展了Pytkowic和Hawley(1974)的碳酸根-碳酸氢根离子对的海水化学模型。  相似文献   

11.
An improved potentiometric titration method for the determination of calcium and magnesium in sea water has been newly devised. In this method, a mini-computer is used for the automation of titrations, and ion-selective electrodes are used as an end-point detector. Calcium is determined by titration with EGTA, and total alkaline earth metals (magnesium + calcium + strontium) by titration with EDTA. Magnesium can be determined by the difference, strontium having been determined by a suitable method. In the present method, calcium and magnesium in sea water can be determined with a precision of 0.1 %.  相似文献   

12.
Abstract

Runoff of phosphorus, nitrate, ammonium, calcium, magnesium, sodium, potassium, chloride, and sulphate was measured in 15 storms and at low flows in 3 “nested” experimental catchments converted from scrub to pasture. Multiple regression analysis suggested that over 2#fr1/2> y, fertiliser application had a cumulative effect on the concentrations of calcium, potassium, and sulphate in storm waters leaving the experimental basin, but only in the flood waters from the small wholly‐grassed sub‐catchment (Pukeiti) was there an increase in phosphorus concentrations. A similar pattern was observed at baseflows. Reactive phosphorus losses of up to 1 kg.ha?1 left Pukeiti in post‐fertiliser storm events but mean losses from the whole basin were only about 0.004 kg.ha?1 per storm and there was little evidence of any fertiliser effect. The stream below Pukeiti has well developed riparian vegetation with marsh and scrub.

The phosphorus losses from the basin seem of little significance agriculturally and environmentally. Although the losses from Pukeiti sub‐catchment were of siufficient magnitude to have a strong impact on water quality in waterways and lakes (mean total phosphorus concentration in post‐fertiliser floods 1.91 g.m?3) this sub‐catchment appeared to have little effect on the quality of water eventually leaving the whole basin.

The results are discussed in relation to sub‐catchment differences and it is suggested that they give support to the use of riparian zones along streams to reduce phosphorus runoff.  相似文献   

13.
矿物质是鱼类必需的营养素之一。海水中含有大量的无机盐,海水鱼类虽可通过饮用海水直接摄取,但是这些矿物质并不能满足鱼类的全部需求,在饲料中还必需予以添加,因此研究海水鱼类对矿物质的需求具有重要的意义。 黑鲷(Sparus macrocephalus)是我国北方最有价值的海水养殖鱼类之一,目前黑鲷养殖业已经逐步发展起来,开展黑鲷营养需求和人工配合饲料的研究已成为当务之急。本文报道了黑鯛对Ca,P,K,Mg和Mn的需求研究结果。  相似文献   

14.
Ten samples of freshwater from Campbell Island were analysed for their main ionic constituents. All show a preponderance of sodium and chloride derived from sea water. Potassium, calcium, and magnesium gave slightly higher concentrations than would be expected if derived solely from sea water. It is con‐eluded that the excess potassium is derived from the underlying rocks and soil, and the excess calcium and magnesium from the sea by fractionation into salt particles.  相似文献   

15.
林学辉  辛文彩  徐磊 《海洋科学》2015,39(12):106-111
利用电感耦合等离子体光谱仪(ICP-AES)对海洋表层沉积物及上覆海水、海洋沉积物国家标准物质、陆地的水系沉积物及土壤国家标准物质进行检测以对比海洋沉积物含水率对部分碱金属及碱土金属元素分析结果所造成的影响。结果显示海洋沉积物含水率对钠离子影响最大,往往有超过50%的钠离子来自其中所含海水的贡献,而海洋沉积物含水率对钾、钙、镁的影响则较为微弱。因此,研究海洋沉积物化学组分时有必要考虑其所含海水对钠含量的贡献,以期达到不同海洋沉积物化学组分的可比性。  相似文献   

16.
Specimens of Bathymodiolus azoricus were sampled along the Mid-Atlantic Ridge at the Menez Gwen, Lucky Strike and Rainbow hydrothermal fields. Individual shells (n = 51), through the weight range 0.62 to 15.70 g, were analyzed for their magnesium, strontium, iron, manganese, copper, zinc and cadmium concentrations. Amongst the marine molluscs the shell of B. azoricus is confirmed as being particularly impoverished in strontium (mean 943 microg g(-1)). Trace metal concentrations in the shells decreased in the order Fe> Mn> Zn> Cu> Cd. Despite originating from trace metal rich environments mean concentrations were low (37.9, 13.2, 10.7, 1.1 and 0.7 microg g(-1), respectively). Irrespective of geographical origin magnesium, strontium and copper concentrations were primarily dictated by shell weight. In contrast cadmium concentrations were elevated in shells from the Rainbow field and ambient seawater chemistry imparted site specific chemical fingerprints to the shells with respect to the iron to manganese ratio.  相似文献   

17.
Methods are described for the complexometric determination of calcium and magnesium in seawater, using an amalgamated silver electrode for end-point detection. In the presence of a small amount of mercury(II)-chelonate, the amalgamated silver electrode serves as a pM indicator during the complexometric titration, the Hg complex being stronger than Ca, Mg and Sr complexes. Calcium is determined by titration with EGTA, calcium+magnesium+strontium by titration with EDTA and magnesium is obtained by difference. Average values of 0.02120 (standard deviation 0.00004) for Ca:Cl‰ and 0.06671 (standard deviation 0.00014) for Mg:Cl‰ were obtained for samples from tropical North Atlantic Ocean.  相似文献   

18.
Water samples taken at 19 locations in the Mawheraiti River catchment at weekly intervals during 1979–80 were analysed for sodium, magnesium, potassium, calcium, phosphate, nitrate, and ammonium ion concentrations and for electrical conductivity. Seasonal discharge effects were apparent, and lithology and land management practice also influenced solute concentrations. Solute concentrations were generally very low; nitrate and soluble phosphate were rarely greater than 0.05 mg.L‐1 and ammonium was rarely greater than 0.01 mg.L‐1. The 4 major cations (Na, Mg, K, and Ca) usually summed to less than 6 mg.L‐1 much of which was supplied by precipitation. Forest management (clearfelling and slash‐burning) caused significant increases in solute concentrations, but concentrations declined rapidly during succeeding months and approached pretreatment levels after 2–3 years. The higher concentrations associated with forest management in small experimental catchments were rapidly diluted downstream; together with the low natural solute concentrations this suggests that harmful downstream effects of management practices are unlikely under low flow conditions.  相似文献   

19.
The conditional stability constant of HSO4? has been determined at 25°C, 1 atm and a formal ionic strength of 0.7 M in solutions containing sodium, magnesium, chloride and sulphate. This was done spectrophotometrically (UV), using diphenylamine as indicator. The value obtained was 17.0 ± 0.1 (molar scale). Single ion activity coefficients for Na2SO4, K2SO4 and MgSO4 have been calculated according to the Bates et al. (1970) model, assuming that the sulphate ion is not hydrated. It was found that the single ion activity coefficient of sulphate changes very little between Na2SO4, K2SO4 and MgSO4 when the formal ionic strength is kept constant.These results have been used to obtain relations between the stability constants of NaSO4? and MgSO4 valid for seawater.  相似文献   

20.
The concentrations of rare earth elements (REEs), sulphate, hydrogen sulphide, total alkalinity, calcium, magnesium and phosphate were measured in shallow (<12 cm below seafloor) pore waters from cold-seep sediments on the northern and southern summits of Hydrate Ridge, offshore Oregon. Downward-decreasing sulphate and coevally increasing sulphide concentrations reveal sulphate reduction as dominant early diagenetic process from ~2 cm depth downwards. A strong increase of total dissolved REE (∑REE) concentrations is evident immediately below the sediment–water interface, which can be related to early diagenetic release of REEs into pore water resulting from the re-mineralization of particulate organic matter. The highest pore water ∑REE concentrations were measured close to the sediment–water interface at ~2 cm depth. Distinct shale-normalized REE patterns point to particulate organic matter and iron oxides as main REE sources in the upper ~2-cm depth interval. In general, the pore waters have shale-normalized patterns reflecting heavy REE (HREE) enrichment, which suggests preferential complexation of HREEs with carbonate ions. Below ~2 cm depth, a downward decrease in ∑REE correlates with a decrease in pore water calcium concentrations. At this depth, the anaerobic oxidation of methane (AOM) coupled to sulphate reduction increases carbonate alkalinity through the production of bicarbonate, which results in the precipitation of carbonate minerals. It seems therefore likely that the REEs and calcium are consumed during vast AOM-induced precipitation of carbonate in shallow Hydrate Ridge sediments. The analysis of pore waters from Hydrate Ridge shed new light on early diagenetic processes at cold seeps, corroborating the great potential of REEs to identify geochemical processes and to constrain environmental conditions.  相似文献   

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