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1.
竹环填料生物滤器在两种海水鱼养殖废水处理中的运行效果及微生物群落分析 总被引：2，自引：0，他引：2
以点带石斑鱼(Epinephelus malabaricas)、半滑舌鳎(Cynoglossus semilaevis)养殖排放水为处理对象,在生产现场研究了竹环填料生物滤器处理高盐度、低氨氮负荷海水养殖废水的运行效果以及挂膜阶段和稳定运行阶段微生物群落变化规律。结果表明,点带石斑鱼养殖废水进水氨氮质量浓度为0.93～1.33 mg/L,氨氮去除率达到27%～39%,挂膜时间需45 d;半滑舌鳎养殖废水进水氨氮质量浓度为0.38～0.52 mg/L,氨氮去除率达到20%～30%,挂膜时间需65 d。另外,对生物滤器挂膜阶段和稳定运行阶段的氨氧化细菌数量和亚硝酸氧化细菌数量进行了统计,氨氧化细菌的数量在点带石斑鱼和半滑舌鳎养殖排放水处理系统中分别达到104～105 CFU/mL和103 CFU/mL,亚硝酸氧化细菌数量则分别达到104 CFU/mL和103 CFU/mL,并分析了温度、进水氨氮负荷、反硝化作用对半滑舌鳎养殖废水生物滤器亚硝酸盐积累现象的影响。 相似文献
2.
为了分离好氧反硝化细菌,探究其好氧反硝化过程。利用BTB培养基,从珍珠龙胆(♀Epinephelus fuscoguttatus×♂Epinephelus lanceolatu)循环水养殖系统的生物滤池中筛选出具有硝酸盐去除能力的细菌,并选择脱氮效果良好的菌株进行好氧反硝化反应器的构建,开展反硝化应用研究。本研究共分离出8株具有去除硝酸盐能力的菌株,经反硝化性能测定,都可大幅去除硝酸盐,同时也存在不同程度的氨氮和亚硝酸盐的积累;选择Z1、Z8两株脱氮效果较好的菌株进行好氧反硝化反应器的混合接种试验,结果显示反应器挂膜迅速、高效,接种2周后即达到相对稳定的水处理状态,硝酸盐去除率超过98.8%(约0.827g NO-3-N/(m2·d)),总氮去除率超过71.8%(约0.687g TN/(m2·d)),亚硝酸盐和氨氮的积累不明显,脱氮效果良好。 相似文献
3.
附着硅藻栖息于海水、淡水或湿润的固体表面，往往同其它微型附着生物形成微生物膜（Primarymicrobialslimefilm）（l、2、’、’、8、’oj。附着硅藻是微生物膜的重要初级生产者之一。研究附着硅藻的数量和分布，对环境的生产力、环境净化和控制以及水产养殖事业，具有现实意义。学者观察到某些附着硅藻种群的有序排列（’门。本文对附着舟形硅藻（NaviculasP．）种群在玻片上附着的空间分布进行了研究。村料和方法1．实验材料1．l培养容器，卧式染色缸（透明硅质玻璃），规格：长7．7X觅5．5X深3C。11。1．2玻片显微镜载玻片，规格：长… 相似文献
4.
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
5.
大亚湾海域低营养盐维持高生产力的机制探讨Ⅰ 总被引：20，自引：0，他引：20
利用2000年4月大亚湾海域的现场调查数据，分析水体中各种形态氮的含量，分布、转化及其影响因素，探讨大亚湾海域低营养盐维持高生产力的原因，调查结果表明：大亚湾海域水体仍属贫氮海区，氮，磷比约为12：1，生产力水平依然受氮控制；大亚湾海域氮以溶解态的形式居多，占总氮的74．8％，颗粒态占25．2％，而溶解态中又以有机氮居多，占总氮的62．1％，孵化实验表明：（1）充氧条件下氨氮向硝氮转化，缺氧条件下硝氮向氨氮转化；（2）水体中溶解有机氮在有氧条件下可以降解转化为无机氮，这意味着占绝对优势的溶解有机氮降解转化为无机氮可能是大亚湾海域低营养盐维持高生产力的主要原因之一。 相似文献
6.
哑铃湾网箱养殖海域沉积物中的氮 总被引：1，自引：0，他引：1
2003年1月采集了哑铃湾网箱养殖区和非养殖区的沉积物柱状样,对氮的垂直剖面和沉积物-海水界面的通量进行了比较研究。结果表明,养殖区和非养殖区氮的垂直剖面和通量存在很大差异。交换态NH4 -N和交换态氮养殖区随深度的增加而降低,非养殖区随深度的增加而增加;非交换态氮养殖区与非养殖区差异不大;其它各形态氮一般随深度的增加呈降低的趋势。除非交换氮以外,各形态氮的含量表层和近表层养殖区明显高于非养殖区,养殖年限越长含量越高。氮的通量,主要是氨氮的通量,养殖区为80.54mg/(m2.d),非养殖区仅为5.58mg/(m2.d),养殖较长时间现已停养的海区也达到了86.18mg/(m2.d)。 相似文献
7.
讨论了中国第六次南大洋考察4条断面1个海湾计30个剖面海水中碘的赋存形式及化学形态的生物地球化学分布。结果表明，表层海水总无机碘含量分有值在0．267－0．443μmol／dm3之间；海水无机碘及碘酸根含量的垂直分布与营养盐关系密切，溶解有机碘分布则较稳定，其含量约为总无机碘的10％。真光层内浮游植物对碘的吸收同化速率为0．17μmol／（m2·d），悬浮有机颗粒中碘的结合量约为4．3μmol／m3，真光层内颗粒碘的下沉速率大于7．2d／m。根据讨论结果提出了测区真光层内碘循环的生物地球化学模式。 相似文献
8.
通过在高度富营养化的海水泻湖——厦门贸彗湖开展龙须菜（Gracilaria lemaneiformis）的延绳夹苗挂养与网笼挂养实验和室内端足类啃食海藻实验，探讨了影响筼筜湖龙须菜生长的主要因素。结果显示，筼筜湖龙须菜的表观生长率为0．42％／d，实际生长率为4．80％／d，强壮藻钩虾（Ampithoe valida）的摄食量占龙须菜总生长量的91．4％。而且，筼筜湖的水流缓慢，使藻体附着最高可达2．32g／gFw的颗粒物，明显抑制了龙须菜的生长。以上研究表明，端足类的啃食作用和不良的水动力条件是导致筼筜湖龙须菜表观生长率低的主要原因。 相似文献
9.
研究了凡纳滨对虾集约化养殖池塘中挂设不同密度的纳米生态基对养殖水质及对虾生长的影响。试验共使用12口养殖池,生态基的挂设密度分别为0.029,0.043和0.058 m2/m3水体,以不挂设纳米生态基的养殖池为对照。结果表明,挂设纳米生态基能明显降低养殖水体的氨氮、亚硝氮和COD含量,挂设生态基处理组池塘水体中氨氮与对照组之间差异显著(P0.05),亚硝氮在试验第7 d后差异显著(P0.05);纳米生态基能较好的稳定池塘水体的DO水平,增氧时DO增加速度与挂设生态基的密度成正比,增氧关闭时DO减小速度与挂设生态基的密度成反比;生态基能提高凡纳滨对虾产量并有效降低其饵料系数,对虾产量分别比对照组高出0.8%,15.3%,3.2%,饵料系数分别降低17%,40%,26%。当对虾放苗密度为150尾/m2时,在本研究设计的梯度范围内,生态基的最佳挂设密度为0.043 m2/m3水体。 相似文献
10.
用乙炔抑制法和最大或然数（most probable number,MPN）法对黄海北部海域沉积物反硝化速率及反硝化细菌数量的季节变化进行了研究,结果表明,该海域反硝化速率在夏季最大,范围在3．2～7．5μmol／（m^2·h）之间,平均值为4．85μmol／（m^2·h）;而在春、秋季其范围分别为0．26～2．65μmol／（m^2·h）和1．21～4．12μmol／（m^2·h）。该研究海域3个季节反硝化细菌数量差别较大,春、夏、秋季分别在1．78×10^4～8．12×10^4,1．18×10^6～6．18×10^6和0．72×10^5～4．50×10^5个／g之间。春、秋两季反硝化速率和反硝化细菌数量之间呈显著性正相关,相关系数分别为0．759和0．750（P〈0．05）。本结果可为黄海北部海域氮循环机制研究提供重要参考。 相似文献
11.
Maintaining stable water quality is one of the key processes for recirculating coral aquaculture. Traditional aquarium systems which mainly utilized a nitrification of nitrifying bacteria attached to the surface of massive artificial filter material are difficult to maintain the oligotrophic conditions necessary for coral aquaculture. This study investigated the removal effects of dissolved inorganic nitrogen(ammonia and nitrate) by live rock(LR), a key component in the "Berlin system" coral aquarium. The expression levels of bacterial functional genes, AOA3,amo A and nos Z, were measured on the exterior and interior of LR. The nitrifying and denitrifying bacterial abundance on LR was quantified and the nitrogen nutrient regulatory effects of LR were evaluated. The results demonstrated that LR mainly removed ammonium(NH_4~+) from the water with a mean efficiency of 0.141 mg/(kg·h), while the removal of nitrate(NO_3~–) was not significant. Bacterial diversity analysis showed that ammonia-oxidizing bacteria(AOB) were the most common bacteria on LR, which accounted for 0.5%–1.4% of the total bacterial population, followed by denitrifying bacteria, which accounted for 0.2% of the total population, and the ammonia-oxidizing archaea(AOA) were the least common type(0.01%). The low abundance of denitrifying bacteria may be responsible for the poor nitrate(NO_3~–) removal of LR. Thus, other biological filtration methods are needed in coral aquaria to control nitrates generated from nitrification or biological metabolism. 相似文献
12.
13.
池塘淤泥对水中氮营养盐影响的初步研究 总被引：3，自引：0，他引：3
通过对不同厚度淤泥水中氮营养盐的测定和分析,初步研究了不同厚度淤泥对水族箱水质环境中氮营养盐的影响。实验结果表明,有淤泥水族箱水中的氨氮浓度与无淤泥水族箱水中氨氮浓度差异显著,且有淤泥水中的氨氮浓度变化幅度较小。有淤泥水族箱水中硝酸盐和亚硝酸盐浓度显著高于无淤泥水体,10cm厚淤泥水中亚硝酸盐浓度变化较5cm厚淤泥水体稳定。由此说明,养殖水体需要一定厚度的淤泥来维持和缓冲水体中各营养盐水平。 相似文献
14.
建立了测定天然海水中硝酸盐氮同位素组成的蒸馏法,该方法主要是在碱性条件下利用戴氏合金将海水中的硝酸盐还原为氨,后利用稀盐酸吸收生产的氨,将得到的氨吸收液浓缩后干燥结晶,利用同位素比值质谱仪测定所得晶体的氮同位素组成。研究中开展了戴氏合金添加量及氨吸收溶液在不同条件下干燥结晶对氮同位素测值的影响研究。结果表明,戴氏合金添加量为3.0 g及60 ℃下直接干燥结晶为最佳的实验条件。所建立的氨蒸馏法氮空白值仅为(0.90±0.19) μmol,低于此前文献报道的氮空白值;氮同位素组成(δ15N)空白值为(-14.7±4.1)×10-3。运用所建立的氨蒸馏法实测得到的硝酸盐δ15N值与氨扩散法、硝酸盐直接测定法得到的数值非常吻合,进一步证明所建立氨蒸馏法的可靠性。改进后的氨蒸馏法适用于硝酸盐浓度在2~50 μmol/dm3内的天然海水硝酸盐氮同位素组成的测定,方法的标准偏差为±0.3×10-3。 相似文献
15.
A method has been developed for determination of15N isotope ratio in nitrate nitrogen, which is a major analytical step in tracer experiments for studies of nitrate metabolism
in the marine environment. The method is based on diazotization of nitrite with sulfanilic acid following reduction of nitrate
to nitrite by a cadmium-copper column. The diazonium compound is then subject to the azo coupling reaction with 2-naphthol,
and the azo dye formed is extracted by a solid phase extraction column. The dye eluted from the column is collected, and total
nitrogen and15N content of the dye are determined by mass spectrometry. Sulfanilic acid can also remove preexisting nitrite by heating the
sample under acidic conditions before passing through the cadmium-copper reduction column. The average recovery of nitrate
nitrogen was 86%. A procedure for reducing the background nitrogen that derives from the analytical operations has been developed;
background nitrogen was limited to about 0.25 μg-atomN. The variation in the background nitrogen levels reflects the range of error in15N determination of nitrate nitrogen by this method. Application of the present method to a15NO3
− isotope dilution experiment for determination of nitrification rate in sea water is demonstrated. 相似文献
16.
Modified Method for the Analysis of Nitrogen Isotopic Composition of Oceanic Nitrate at Low Concentration 总被引：1，自引：0，他引：1
A method for the determination of the δ15N of nitrate in seawater described by Cline and Kaplan (1975) has been modified for application to low-level nitrate samples.
We have minimized the reagent blank problem by replacing the Devarda's alloy with an aluminum reagent, and have also established
a procedure that yields quantitative (93 ± 2%) extraction of nitrogen even at low nitrate levels. Though the amounts and the
δ15N of the blank N varied from one reagent set to another, with these modifications, an overall N blank was reduced to approximately
0.80 ± 0.33 μmole N having an estimated δ15N value of −1.8‰. After blank and yield corrections, the measured isotopic composition of nitrate differed by approximately
0.1‰ from the actual value while the precision was within ±0.2‰ at the 1.25 μM level. The modified procedure was applied to
seawater samples collected from the equatorial Pacific in order to compare the N blanks in field samples with those derived
from laboratory experiments. The results support the suitability of the modified approach for isotopic analysis of oceanic
nitrate in shallow water.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
17.
18.
《Marine Policy》2014
Papua New Guinea has sometimes been called the world's last frontier for relatively undamaged coral reefs and their resources. In 2007, the country joined its neighbours in the marine aquarium trade. By licensing a private company, Papua New Guinea tried an alternative approach to the introduction of this activity. Under the so-called SeaSmart Programme, over 100 fishers were trained in sustainable collection techniques and handling of organisms, until the programme was shut down in 2010, and replaced by its successor, EcoAquariums PNG. This article contains the first study on the introduction of the marine aquarium trade into Papua New Guinea. It evaluates the overall outcomes of the SeaSmart Programme, lists targeted species, and their prices. The main focus is on the local collectors, and on the impacts of this new activity on them and their communities. Benefits from collecting marine ornamentals are assessed and their contribution to household income is quantified. Perceptions on non-financial benefits of the SeaSmart Programme are also gathered. The empirical work was carried out between September 2010 and February 2011 in the Central Province of Papua New Guinea. A total of 199 fishers including 44 aquarium fishers were interviewed in eight different communities in the Central Province of Papua New Guinea. The results show that marine aquarium fishing does provide benefits to local resource collectors, but also that this “sustainable” way of collecting of marine ornamentals might lead to some depletion. 相似文献
19.
During 1985～1987,the concentration of nitrate nitrogen was higher in the Laizhou Bay and the Bohai Bay while that of nitrite nitrogen was higher in the Liaodong Bay and the Bohai Bay,The concentration of nitrate nitrogen was highest in winter and lowest in summer while that of nitrite nitrogen was highest in autumn and lowest in spring .the seasonal variation of the concentration of nitrate nitrogen was maximum in the Laizhou Bay and the Bohai Bay while that of the concentration of nitrite nitrogen was maximum in the Liaodong Bay.There was a great difference in the concentration of nitrate nitrogen between the surface and the bottom in autumn and in the concentration of nitrite nitrogen between the surface and the bottom in summer.The main reason for the seasonal variations of the concentration of nitrate nitrogen and nitrite nitrogen was the marine biochemical process.The nitrate nitrogen and nitrite nitrogen in the Bohai Sea basically maintained a quasi-equilibrium state seasonal cycle,The quesi-equilibrium state seasonal cycle of nitrate nitrogen and nitrite nitrogen at the bottom was stable while that at the surface was liable to variations caused by other factors. 相似文献
20.
《African Journal of Marine Science》2013,35(1):333-343
A closed system, supplied with water from the Indian Ocean and stocked with the prawn Penaeus monodon, was used to identify and study the cultural characteristics of the associated marine nitrifying bacteria. This system provided the ideal environment for the development of nitrifying bacteria, which was monitored by assaying for the oxidation of either ammonia or nitrite. As these organisms grow very slowly, enrichment and fed-batch cultures were prepared to obtain pure cultures. The nitrifying bacteria are chemolithotrophs and can only be identified by observing their arrangement of internal or cytomembranes with the aid of the transmission electron microscope. All five listed genera of marine nitrifying bacteria were observed, namely Nitrosomonas and Nitrosococcus, which oxidize ammonia to nitrite, and Nitrobacter, Nitrococcus and Nitrospina, which oxidize nitrite to nitrate. Nitrosomonas europaea and Nitrobacter winogradskyi represented the dominant organisms in enrichment cultures and were also obtained in pure culture. Examination of the colonial morphology indicated the lack of distinct characteristics that could aid in their identification. A simple, effective method of observing the growth of ammonia-oxidizing bacteria microscopically, based on the breakdown of magnesium ammonium phosphate, is also described. 相似文献