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1.
海岸带盐度过渡区域水体中氮、磷的准确测定对陆海统筹及海岸带管理起着至关重要的作用。为探究盐度对氮、磷测定准确度的影响,进而明确河口海岸带淡水-咸水盐度过渡区不同形式氮、磷测定方法的选择依据,分别采用淡水和海水的相关国家标准方法,测定不同盐度下不同质量浓度氮、磷的人工海水和天然海水水样中氨氮、亚硝氮、总氮、活性磷酸盐和总磷的质量浓度。结果表明,盐度对某些氮、磷的淡水法和海水法测定结果有一定程度的影响。对氨氮的测定,当S≤4.0时淡水法或海水法均可准确测定水体中的氨氮,S>4.0时应对水样进行pH 调整预处理后用海水法进行测定;对亚硝氮的测定,淡水法和海水法的测定结果无明显差异;对总氮的测定,当S≤5.0时应采用操作简单、测定准确的淡水法测定,S>5.0时应采用海水法。对水体中的活性磷酸盐的测定,在低盐低磷(S≤35.0且ρPO3-4 ≤0.2mg·L-1)的情况下盐度对淡水法和海水法测定结果的影响微乎其微,而对于高盐高磷(S>35.0且ρPO3-4 > 0.2mg·L-1)的水样选择灵敏度更高的海水法测定更准确;对总磷的测定,选取海水法测定准确度更高。研究结果为海岸带水体不同形式氮、磷质量浓度的准确测定与方法选择提供了科学依据。  相似文献   

2.
海水中总氮和总磷的同时测定   总被引:24,自引:0,他引:24  
早期总氮和总磷的过硫酸钾法氧化分析分别是在碱性和酸性介质中进行[1,2],样品分别保存,然后分别氧化测定,工作较繁琐。1977年Koroleff用过硫酸钾氧化法同时氧化水体中的总氮和总磷,使样品的保存和氧化分析工作简化。1981年Valderrama对该方法测定天然海水中的总氮和总磷做了进一步研究,总氮和总磷同时氧化后,水样中的硝酸盐和磷酸盐用手工分别进行分析。Walsh1989年和Karl等1993年曾采用UV光氧化法对海水中总溶解氮和总溶解磷进行同时氧化后,用自动分析对氧化后的无机氮和磷进行…  相似文献   

3.
分别采用硫酸过硫酸钾作为氧化剂进行高压消解和用浓度为1 mol/dm3盐酸浸泡提取,然后用磷钼蓝分光光度法测定海水悬浮颗粒物、沉积物中的总磷和无机磷,用差减法得到有机磷。悬浮颗粒物总磷(PTP)和无机磷(PIP)质量浓度分别为(632.4~651.7)×10-6和(436.6~452.6)×10-6时,其相对标准偏差小于1.44%。悬浮颗粒物总磷、无机磷和有机磷的回收率分别为97.2%~101.3%,97.8%~100.4%和97.3%~102.3%。所建立的分析方法可用于海水、河口水悬浮颗粒物及沉积物中不同形态磷的测定。  相似文献   

4.
海水中磷氮不同形态的同时测定   总被引:1,自引:0,他引:1  
采用过硫酸钾-硼酸-氢氧化钠混合试剂作为氧化剂,同时测定海水中总磷、氮和总溶解态磷、氮,从而建立了海水中磷、氮不同形态的分析流程及步骤。总磷、总溶解态磷浓度为0.35~1.09μmol/dm3时,相对标准偏差小于6.6%;总氮、总溶解态氮浓度为11.8~54.8μmol/dm3时,相对标准偏差小于5.6%。总磷、总溶解态磷和总氮、总溶解态氮的回收率分别为95.0%~106.0%和94.0%~106.0%。本文的分析方法可用于对近岸海水及河口水中磷、氮不同形态的同时测定。  相似文献   

5.
南黄海沉积物中氮、磷的生物地球化学行为   总被引:11,自引:4,他引:11  
于2004年10月采集南黄海4个站位的柱状沉积物和29个站位的表层沉积物,用氧化浸取分光光度法研究了自然粒度下沉积物中的氮、磷分布特征以及控制其分布的生物地球化学机制。结果表明,多数站位随着沉积深度的增加,沉积物中氮、磷浓度趋于稳定。4个站稳定时氮浓度平均约为289μg/g,磷约为329μg/g,平均稳定浓度出现的沉积层次分别为氮>30cm,磷>22cm。氮、磷垂直分布形状的规则性与沉积速率密切相关,沉积速率越小的站位,其氮、磷垂直分布愈规则;海洋沉积物中的氮主要来源自海洋生物的代谢,而磷与陆源碎屑输入密切相关。氮与沉积物粘土含量、浮游动物生物量干重有明显的正相关关系。海水中浮游动物干重每增加1mg/m3,则沉积物中氮浓度增加5.64μmol/g,磷不存在这样的关系。沉积物中氮的早期成岩速率远高于磷,在沉积物海水界面附近氮约为磷的7.4倍。海水浮游生物生物量与沉积物中氮的早期成岩类型密切相关,在所研究的2004年秋季海水中,浮游动物生物量干重19mg/m3是沉积物中氮早期成岩类型转变的界限值,小于这一界限值,水体中的氮趋向于向沉积物中凝聚;大于19mg/m3,则沉积物中的氮趋向于向水体释放。  相似文献   

6.
海水苦卤中可溶性糖的测定   总被引:3,自引:0,他引:3  
建立了一种海水苦卤中可溶性糖的测定方法。研究确定了苯酚-硫酸法测定海水苦卤样品中可溶性糖的最佳实验条件。在加入苯酚60mg、90℃水浴加热20min的条件下,显色体系在490nm处的吸光度达到最佳值,糖的浓度在1—100μg.ml-1范围内符合比尔定律,线性相关系数为0.999 7。该方法具有简便、快速、稳定性好、干扰因素少的特点,且样品基本无需预处理。用所拟方法对广东省徐闻县盐场制盐苦卤中的可溶性糖进行测定,相对标准偏差为1.73%(n=6),加标回收率在94.80%—102.70%之间,结果满意。应用该方法还成功测定了生态型人工海水添加剂———苦卤提取物中糖的含量。  相似文献   

7.
研究污水处理厂产生的污泥脱水液中的磷酸盐(PO43-)和铵盐(NH4 )的去除方法。依据化学沉淀法的原理,含有Ca2 和Mg2 的海水加入污泥脱水液后,可以使污水中的PO43-与金属离子发生化学沉淀反应,实现污水除磷的目的。采用正交试验优化得到这种方法处理污泥脱水液的工艺条件:水温20℃,海水与污水混合比例为2∶10,体系pH值为10.5,反应时间20min。经过静态处理,污泥脱水液中氨态氮(NH4 -N)的平均去除率为34%,无机磷(PO43--P)的平均去除率为95%,比不投加海水的处理提高26%,这表明投加海水有利于强化污泥脱水液的除磷效果。动态处理也有较好的效果,PO43--P和NH4 -N的去除率分别可达91%和18%。这种技术不仅除磷效果好,处理成本也较低,生成的沉淀物还可以作为肥料施用,因而是污泥脱水液除磷的有效途径,特别适用于沿海地区污水处理厂。  相似文献   

8.
本文介绍一种海水中痕量苯的富集与气相色谱测定方法。用国产高分子微球GDX-502 为吸附剂,富集海水中痕量苯后,热解吸,用冷阱浓缩,再热解吸,然后直接进行色谱测定。方法简便、易于操作,且灵敏度高。该法已在青岛胶州湾沿岸及小青岛附近表层水苯含量的测定中进行过验证。  相似文献   

9.
自从水俣病发生以来,人们对环境中汞的含量愈益重视。据报道海水中汞的浓度为0.5—364ngl~(-1),其含量虽如此之微,但为了准确测定不同海域海水中汞含量的自然背景值及评价不同海区水域是否受到汞污染,则要求测定方法具有很高的灵敏度和低的检出限。为了使方法的灵敏度能适应于测定海水中的汞含量,曾采用过预浓缩后进行冷原子吸收测定的方法。近年来,为提高汞的冷原子吸收测定方法的灵敏度  相似文献   

10.
胶州湾海水中无机氮的分布与富营养化研究   总被引:27,自引:4,他引:23  
根据2003年112月胶州湾海区12个航次海水无机氮等的调查资料,分析了该海域生态环境中无机氮的分布特征及时空变化,评价了水质的富营养化状况。结果表明,测区全年溶解无机氮的平均含量为17.70μmol/dm^3。在4个季节中,溶解无机氮以NO3-N的含量为最大,占58.2%,是氮主要存在形态,其中秋季含量最高,占溶解无机氮的64.74%。无机氮分布从东北部高含量区域向湾内及湾口方向呈逐步递减趋势。溶解无机磷的年平均含量为0.49μmol/dm^3,表层海水4个季节中N/P比平均为39.41,胶州湾海水中的磷相对于氮是匮乏的。据营养状态指数划分,胶州湾的东、北岸海域属富营养化区,夏、秋两季可能受到赤潮的严重威胁。  相似文献   

11.
营养盐对螺旋藻脂肪酸组成和含量的影响   总被引:1,自引:0,他引:1  
本文研究不同浓度的氮、磷和碳以及不同的氮源对螺旋藻脂肪酸组成和含量的影响.结果表明改变营养盐的浓度对藻体TSFA和TPUFA均有较大影响,而对TMUFA无显著影响;氮源NaNO  相似文献   

12.
Himmerfjärd is a Swedish estuary bordering on the Baltic. The estuary lacks astronomical tides and its circulation is driven by winds and freshwater runoff. Because of a tertiary sewage treatment plant located at its inner end, the estuary is becoming increasingly eutrophic. A field study was carried out for a 78-day period in late summer and early fall of 1977 to determine rates of nutrient transport and to construct nutrient budgets. Since physical parameters (current velocity, temperature, salinity, winds and water level changes) were measured more frequently than nutrients (phosphate, nitrate, nitrite and ammonium) it was necessary to develop a suitable method to calculate nutrient flux time series and net nutrient fluxes. Over the study period, Himmerfjärd imported phosphorus and exported nitrogen. Direction of nutrient fluxes and changes in flux direction were consistent with the structure of the baroclinic currents.  相似文献   

13.
The size-related activities of important heterotrophs and autotrophs were compared at the surface and at the subsurface chlorophyll maximum (Chlmax) in Agulhas Bank waters. The netplankton fraction was dominated by Nitzschia spp. and ciliates, small (diameter c. 3μm) microflagellates being the most abundant nanoplankton group. Uptake ratios of ammonium to phosphate for the total microplankton community were different at the two depths. With reference to the Redfield ratio, it appears that at least 48 per cent of the nitrogen ration at the Chlmax was regenerated even though nitrate was in ample supply. These assimilation ratios also suggest a very large contribution from recycled nitrogen other than ammonium in surface waters. It is unlikely that phosphorus would ever become limiting, except perhaps at the primary production maximum. Microplankton uptake and regeneration of both ammonium and phosphorus were approximately in balance, indicating that variations in assimilation ratios were the result of heterotrophic excretory activity. The size-fractionation studies show that picoplankton were on average the single most important size class in nutrient assimilation. The netplankton size class was, in terms of regeneration, often the most active in the microplankton community especially within the Chlmax. Heterotrophic microflagellates and picoplankton supplied the bulk of ammonium and phosphorus at the surface. The importance of a particular size class to either ammonium or phosphorus uptake/excretion was quantified as a relative assimilation/regeneration index. These calculations demonstrate size-related differences in the relative importance of the microplanktonic groups to the immobilization and recycling of different nutrients.  相似文献   

14.
Nitrogen and phosphorus contents are analyzed in the overlying waters and pore waters taken from the Changjiang Estuary and Shanghai coastal tidal flats in this study. In addition, the diffusion fluxes of nitrogen and phosphorus across the sediment-water interface in tidal flats are estimated according to the nutrient concentration gradients at the interface. It has been indicated that the concentrations of ammonium, nitrite, nitrate and dissolved phosphorus in overlying waters range from 0.0082~2.56, 0.03~0.58, 0.69~5.38 and 0.035~0.53 mg/L, respectively, while 0.0025 ~ 1.35 mg/L for NH4+-N, 0. 0055 ~ 0.20mg/L for NO2--N, 0.61~1.14 mg/L for NO3--N and 0.11~0.53mg/L for DP insurface pore waters.The findings have revealed that ammonium, nitrite, nitrate and dissolved phosphorus diffusion fluxes across the sediment-water interface are between -0.024~0.99, -0.39~ -0.0019, -3.09~the source of phosphorus and an important sink for nitrogen in the waters.  相似文献   

15.
均匀设计在后棘藻培养基中的应用   总被引:2,自引:0,他引:2       下载免费PDF全文
将均匀设计的方法应用于一种海洋微藻:后棘藻(Ellipsoidion)培养基的优化。设计了硝氮、氨氮、磷酸盐三因素各五个浓度水平的试验,根据均匀设计表设计了10种培养基,检测细胞浓度、脂肪酸含量和产量。结果表明:在硝氮、氨氮浓度均为1.92mmol/L,磷酸盐浓度为0.082mmol/L,细胞浓度达到最大值167.23mg/L。在硝氮浓度为0.84mmol/L,氨氮浓度为3.38mmol/L,磷酸盐浓度为0.07mmol/L时,EPA含量达到最大值7.748%。在硝氮浓度为0.915mmol/L,氨氮浓度为1.92mmol/L,磷酸盐浓度为0.072mmol/L时,EPA产量达到最大值9.999mg/L。  相似文献   

16.
The aim of this study was to investigate nitrogen and phosphorus released in the process of the decomposition of giant jellyfish in the laboratory and found the evidence to verify the influence of nutrients released by the decomposition of jellyfish on the ecosystem in the field. The release of nitrogen and phosphorus from the decomposition of Nemopilema nomurai was examined in a series of experiments under different incubation conditions such as different p H values, salinity values, temperatures and nitrogen and phosphorus concentrations. The results showed that the complete decomposition of Nemopilema nomurai generally took about 4–8 d. The release of nitrogen and phosphorus from the decomposition of Nemopilema nomurai could be divided into two stages: the early stage and the later stage, although the efflux rate of nitrogen was one order more than phosphorus. In the early stage of the decomposition of Nemopilema nomurai, the concentrations of dissolved nitrogen, dissolved phosphorus, total nitrogen and total phosphorus in seawater increased rapidly, and the concentration of nitrogen could reach the highest level in the whole degradation process. In the later stage of the decomposition, the concentrations of dissolved nitrogen and total nitrogen declined slowly, while the concentration of phosphorus in water could reach a maximum in the degradation process. High p H, low salinity,high temperature and N/P will promote the release of nitrogen; low p H is unfavorable to the release of nitrogen but favorable to the release of phosphorus. In addition, we found the concentrations of ammonium and phosphate in the bottom water were higher than those in the surface water during the period of jellyfish bloom in the Jiaozhou Bay, proving that nutrients released by the decomposition of jellyfish have significant influence on nitrogen and phosphorus in the field. For the whole Yellow Sea, nutrients released by jellyfish carcasses may reach up to(2.63±2.98)×107 mol/d of dissolved nitrogen(DN) and(0.74±0.84)×106 mol/d of dissolved phosphorus(DP) during the period of jellyfish bloom. The values are comparable to riverine inputs in a day, but much higher than sediment–water exchange flux in the Yellow Sea. The great amounts of nutrients must have significant influence on the nutrients balance of the Yellow Sea during the period of jellyfish dead and decomposition. Both the experimental data and field observations proved that the decomposition of jellyfish may release a great amount of nutrient to the surrounding environment during the period of jellyfish decomposition.  相似文献   

17.
用长效肥料提高微生物分解海面油膜试验   总被引:1,自引:0,他引:1  
氮和磷是限制海洋油污生物降解的重要因素,采用可被微生物分解的两种蜡的混合物,把含有10:1的氮和磷的无机盐粉末包埋起来,制成亲油性且能与油膜漂浮在一起的长效肥料。在室内进行促进海水表面柴油油膜的生物氧化实验,结果表明:制备的长效肥料有促进油膜中烃类氧化微生物的生长和柴油的生物降解作用,实验9天除油率达到57 4%,对照实验仅24.5%。  相似文献   

18.
利用样带与样方结合法进行野外调查,测定土壤主要理化指标,基于SPSS 24. 0进行皮尔逊(Pearson)相关性分析、单因素方差(One-way ANOVA)分析和最小显著差数法(LSD)多重比较,对小钦岛土壤理化性质的统计学特征及其影响因子进行研究.小钦岛土壤砾石比和含水量平均值分别为20. 04%、7. 35%;铵态氮、速效钾、速效磷、有机质含量平均值分别为23. 67、212. 77、16. 15mg/kg、28. 34 g/kg,分别属于五级、一级、三级和三级水平,大部分属于三级土壤;有机质与含水量、铵态氮、速效磷均呈显著正相关.土壤理化性质主要受植被和坡向影响.通过丰富、加深对庙岛群岛的研究,旨在为海岛的生态保护及开发提供参考.  相似文献   

19.
目的:观察外伤一方加减治疗手足外伤的临床疗效。方法:将手足外伤患者80例随机分为2组,每组各40例,对照组采用西医常规治疗,治疗组在对照组治疗基础上加本院自制的外伤一方治疗。比较2组患者的综合疗效、VAS评分及满意率。结果:总有效率治疗组为100.0%,对照组为85.0%,组间比较,差异有统计学意义(P<0.05);2组疼痛VAS评分及患者满意率比较,差异均有统计学意义(P<0.05)。结论:外伤一方加减治疗手足外伤有较好的临床疗效,能明显降低患者疼痛程度,提高患者治疗满意度。  相似文献   

20.
过硫酸盐氧化法测定海水中溶解总磷   总被引:6,自引:0,他引:6  
实验研究在碱性和酸性条件下过二硫酸钾高温氧化四种不同类型含磷标准化合物在海水中的回收率和影响回收率的因素。结果表明 :在碱性条件下过二硫酸钾高温氧化可使海水中非聚磷类化合物完全回收 ,而聚磷类化合物回收率不高 ,延长消化时间聚磷类化合物的回收率有一定提高。除个别化合物外 ,各类含磷化合物在酸性条件下可被定量回收。依此 ,建立酸性过硫酸盐氧化法分解测定海水中溶解态总磷的方法。  相似文献   

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