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331.
Three Salsola species, Salsola dendroides Pall., S. richteri (Moq.) Karel ex Litw. and S. orientalis S.C. Gmel., were compared for their salt tolerance, inorganic ionic accumulation and their biomass production in saline conditions. Seeds were grown on sterilized quartz under five salinity levels in a factorial experimental design, with four replications, in greenhouse conditions.With salinity, Na+ accumulation increased while K+ accumulation decreased. All three species showed positive shoot growth for low levels of salinity. Root growth showed almost the same trend as shoot growth, with minor exceptions. At low levels of salinity, proline accumulated more in S. dendroides plant tissues than in the tissues of the other two species. These results suggest that the proline accumulation is a good index for salinity tolerance. Soluble sugars also increased as a result of salinity. 相似文献
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333.
将1株产油淡水微藻——微拟球藻(Nannochloropsis sp.MASCC 11)分别接种到青岛市2家市政污水处理厂(STP)的尾水中,根据其生长、油脂产率和营养盐去除情况,评价了利用STP尾水培养微藻以生产富油的藻生物质同时深度净化尾水的可行性。结果表明,团岛污水处理厂(TD-STP)和李村河污水处理厂(LC-STP)尾水中无机氮和磷酸盐的浓度虽然远低于BG11培养基,但仍能支持微藻生长,而且以未经稀释的尾水更具优势,培养8 d后,藻生物量分别达到BG11培养基中生长微藻的65.23%和44.77%。STP尾水经稀释后处于营养盐缺乏状态,有利于藻细胞内脂质积累,但是油脂产率最大值(10.5 mg·L-1·d-1)仍出现在未经稀释的TD-STP尾水中,为未稀释LC-STP尾水的1.37倍。LC-STP尾水中微藻的油脂产率较低,可能与该处理厂接纳工业废水而在尾水中残留较多有害物质有关。在微藻的直接和间接作用下,TD-STP和LC-STP尾水中磷酸盐的去除率分别达到94.5%和100%;无机氮的去除率较低(分别为59.2%和45.4%),与尾水中初始N/P较高有关。上述结果表明,与接纳工业废水的污水厂相比,处理生活污水的污水厂所排尾水较适于培养产油微藻,能够实现产油微藻低耗培养与尾水深度净化相耦合。 相似文献
334.
硫酸钾是一种有着广泛应用的工业原料和农业肥料,其生产技术主要是通过海水或卤水中的硫酸盐与氯化钾反应制得。我国盐湖资源和盐类储量极其丰富,这为硫酸钾的制备生产提供了更多途径。但对于不同水化学类型的盐湖,需采取不同的提钾制备硫酸钾工艺路线。在以往盐湖钾盐提取和硫酸钾生产技术研究的基础上,针对碳酸盐型盐湖扎布耶盐湖中钾盐和硫酸钾的提取和制备方案进行了论述及设计,并指出了蒸发结晶法、化学沉淀法和吸附及离子交换法等几种方法在技术上都有其可行性。但在工业生产中可以考虑将这几种方法有机结合,以达到钾的最大富集,降低硫酸钾生产成本,并有利于保护环境。 相似文献
335.
循环水及污水中总磷的国家标准方法是用分光光度法测定,当样品中有机磷含量高时,分解易碳化,操作繁琐,分析误差大.本文应用磷钼黄显色示差分光光度技术测定某钢厂循环管道除垢污水中的总磷,通过正交实验确立了采用硝酸-高氯酸消解样品,将样品中聚磷酸盐、有机磷酸盐转化为正磷酸盐,在硝酸溶液中,正磷酸盐与钒钼酸铵作用生成可溶性黄色磷钒钼酸配合物,基于其颜色强度与磷的浓度成正比测定高浓度磷的含量.实验对使用的氧化剂用量、溶解温度、显色条件、测定波长进行优化,结果表明,磷含量在10.0 ~ 40.0 mg/L范围符合朗伯-比尔定律,方法精密度(RSD)<1.0%(n=5),加标回收率为98.8%~105.0%.建立的示差光度法比一般光度法相对误差小,准确度更高;与电感耦合等离子体发射光谱法的测定结果基本吻合,且测定成本更低. 相似文献
336.
Surveys were carried out over 16 months to assess the distribution of enteroviruses of human origin in sediments and mussels near two sewage outfalls on the North Taranaki Coast, New Zealand. Enteroviruses were present in high numbers in both sediments and shellfish near the New Plymouth sewage outfall with maximum virus levels of 32 000 pfu 100 g‐1 of wet mussel tissue and 59 pfu 100 g‐1 of wet sediment material. Viruses were recovered occasionally from sediments and mussels near the Waitara Borough outfall. Coxsackievirus B4 was the predominant virus type isolated but CB5 and Poliovirus types 1, 2, and 3 were also recovered. Attempts to depurate virus‐contaminated New Plymouth mussels, by keeping them in water for 8 days with daily water replacement, did not achieve a significant reduction in virus numbers. 相似文献
337.
R. A. Prestidge 《新西兰海洋与淡水研究杂志》2013,47(1):193-199
In a laboratory study of the ingestion and assimilation efficiency of larvae of Aeshna brevistyla Rambur and Hemicordulia australiae Rambur, ingestion was determined using Cerenkov radiation techniques and assimilation efficiency by a double‐labelled isotope technique. Of each prey item (Daphnia carinata), 30% was not ingested but lost as body fluids and as material within the alimentary canal of the prey. Assimilation efficiency was greater than 70% for both dragonfly species, which appears to be typical for most other invertebrate predators. The efficiency with which 12th‐15th‐instar Aeshna assimilated 14C did not increase with feeding rate, but Hemicordulia increased its efficiency through instars 12–14. When dragonfly larvae were pre‐fed before experimentation, assimilation efficiency decreased in both species. 相似文献
338.
Throughout the shores of the world,a confluence of different sources of pollution is common,e.g.,through outlets releasing brine,industrial,and domestic sewage.In this study,we assessed whether a combined disposal of domestic sewage and brine altered the patterns of abundance and assemblage structure of subtidal macrofauna inhabiting sandy seabeds on the south coast of Gran Canaria(Canary Islands,NE Atlantic Ocean).Samples were collected in two surveys(May 2008 and January 2009)at three distances(0,15,and30 m)away from the discharge point.Macrofaunal abundances showed different patterns with varying proximity from the disposal point in the two surveys.In May 2008,lower abundances were observed at0 m(53.89±46.82 ind.)than at 15 m(120±91.7 ind.)and 30 m(283.89±189.33 ind.)away from the disposal point.In January 2009,however,higher abundances were observed at 0 m(131.33±58.69 ind.)than at 30 m(100±24.44 ind.)and 15 m(84.78±58.39 ind.)away from the disposal point.Significant differences in macrofaunal assemblage structure were found with varying proximity from the discharge point in both surveys.The effect of proximity from the disposal point was confounded by changes in sedimentary composition between surveys,which contributed to explain differences in macrofaunal abundances and assemblage structure with varying proximity from the discharge point.As a result,confounding drivers of macrofaunal assemblage structure,here,changes in sediment composition,accounted for changes in macrofaunal abundances and assemblage structure with varying proximity from a combined disposal point of brine and sewage. 相似文献
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340.