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1.
现场及实验室试验表明,近岸水中细菌丰度因时因地有较大差别,近岸水在潮周期中以高潮前后细菌量较低;海水在沉淀贮存过程中细菌丰度有明显变化,且与海水中营养物含量、贮存温度等有关;海水经沙滤后能减少细菌90%左右;回水中脱落苗进入贮水池,是贮水池中细菌数量增长10余倍的主要原因。  相似文献   
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2002年2月—2004年11月对胶州湾异养细菌和大肠菌群进行长期调查发现,胶州湾异养细菌丰度在105—106cells/ml之间,其中河口区域和近岸区域数量较高,其它区域相对较低。从季节上来看,夏季、秋季细菌丰度较高(分别为7.4×105、7.2×105cells/ml),冬季和春季丰度较低(分别为4.1×105cells/ml、5.9×105cells/ml),且在一年内呈现出一定的规律性波动。从季节尺度上看异养细菌丰度与温度呈现很好的正相关性(R=0.54)。对大肠菌群的研究表明,河口区域的大肠菌群数量显著高于其它区域,并且河口区域大肠菌群常年处于严重超标状态(最高为1.1×106cells/L,超过国家前三类水质标准的100倍)。根据大肠菌群的数量状况可以将胶州湾分为三个区域,即严重污染区、中度污染区和轻度污染区。该区域划分与通过营养盐对胶州湾区域的划分(富营养区、中度营养区、贫营养区)结果一致。  相似文献   
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To verify the hypothesis that the growth of phytoplankton in the Western Subarctic Gyre (WSG), which is located in the northwest subarctic Pacific, is suppressed by low iron (Fe) availability, an in situ Fe fertilization experiment was carried out in the summer of 2001. Changes over time in the abundance and community structure of phytoplankton were examined inside and outside an Fe patch using phytoplankton pigment markers analyzed by high-performance liquid chromatography (HPLC) and flow cytometry (FCM). In addition, the abundance of heterotrophic bacteria was also investigated by FCM. The chlorophyll a concentration was initially ca. 0.9 μg l−1 in the surface mixed layer where diatoms and chlorophyll b-containing green algae (prasinophytes and chlorophytes) were predominant in the chlorophyll biomass. After the iron enrichment, the chlorophyll a concentration increased up to 9.1 μg l−1 in the upper 10 m inside the Fe patch on Day 13. At the same time, the concentration of fucoxanthin (a diatom marker) increased 45-fold in the Fe patch, and diatoms accounted for a maximum 69% of the chlorophyll biomass. This result was consistent with a microscopic observation showing that the diatom Chaetoceros debilis had bloomed inside the Fe patch. However, chlorophyllide a concentrations also increased in the Fe patch with time, and reached a maximum of 2.2 μg l−1 at 5 m depth on Day 13, suggesting that a marked abundance of senescent algal cells existed at the end of the experiment. The concentration of peridinin (a dinoflagellate marker) also reached a maximum 24-fold, and dinoflagellates had contributed significantly (>15%) to the chlorophyll biomass inside the Fe patch by the end of the experiment. Concentrations of 19′-hexanoyloxyfucoxanthin (a prymnesiophyte marker), 19′-butanoyloxyfucoxanthin (a pelagophyte marker), and alloxanthin (a cryptophyte marker) were only incremented a few-fold increment inside the Fe patch. On the contrary, chlorophyll b concentration reduced to almost half of the initial level in the upper 10 m water column inside the Fe patch at the end of the experiment. A decrease with time in the abundance of eukaryotic ultraphytoplankton (<ca. 5 μm in size), in which chlorophyll b-containing green algae were possibly included was also observed by FCM. Overall, our results indicate that Fe supply can dramatically alter the abundance and community structure of phytoplankton in the WSG. On the other hand, cell density of heterotrophic bacteria inside the Fe patch was maximum at only ca. 1.5-fold higher than that outside the Fe patch. This indicates that heterotrophic bacteria abundance was little respondent to the Fe enrichment.  相似文献   
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秋季东、黄海异养细菌(Heterotrophic Bacteria)的分布特点   总被引:27,自引:1,他引:27  
2000年10-11月,乘"北斗号"考察船进行秋季"东、黄海生态系统动力学与生物资源可持续利用"大面调查,研究秋季东、黄海异养细菌的分布.结果表明,异养细菌在黄海和东海的丰度分别在(2.37-13.33)×108 cell/L和(3.05-13.62)×108 cell/L之间.细菌丰度最高值出现在长江口附近,且断面E和断面F各站位的细菌丰度明显高于其他断面.异养细菌丰度大小以长江口为中心向外海依次递减.东、黄海水体异养细菌生物量分别在244.45-1812.90mgC/m2和100.60-940.87mgC/m2之间.东、黄海异养细菌丰度无显著差异,但是东海海域水体异养细菌生物量高于黄海海域.异养细菌空间分布与浮游植物叶绿素在东海有一定的相关性,黄海异养细菌与硝酸盐浓度的相关性极显著.  相似文献   
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高爱国  陈皓文 《极地研究》2007,19(3):231-238
本文用MPN法测定楚科奇海和加拿大海盆表层沉积物中好气异养细菌(GAB)的含量,并对其地理学分布进行分析。结果表明,研究区GAB的检出率高达100%。4℃时GAB的含量范围、平均含量为4.00×102-2.40×106个.g-1、1.71×106个.g-1。25℃时GAB的含量范围、平均含量为2.40×105-2.40×107个.g-1、1.10×107个.g-1。无论是含量范围,还是平均含量,均是25℃时的培养结果大于4℃时的培养结果。GAB含量的地理分布趋势是随纬度增高,含量呈降低趋势。在经度变化上则为由东向西,含量呈降低趋势。对沉积物所处水深的分析,表明其在4℃培养得出来的GAB含量随水深增加有下降的趋势,25℃培养出来的GAB含量受环境影响较小,与水深变化关系不明显。  相似文献   
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王艳  汪岷  杨琳  卢龙飞  王健  孙辉 《海洋与湖沼》2013,44(1):198-204
利用流式细胞仪对南黄海秋季浮游病毒丰度在水平分布和垂直分布上的特征进行了研究,并分析了浮游病毒丰度与异养细菌、微微型浮游植物等宿主丰度以及环境因子的相关性.结果表明,该海区秋季浮游病毒丰度在(2.22×106)-(1.60× 107)ind/ml之间,平均值8.32×106ind/ml.病毒丰度在调查海域的东北和中南部海域出现高值区,在西南部出现低值区,且浮游病毒丰度与异养细菌丰度的平面分布趋势较一致.在表层、中层和底层水体,浮游病毒丰度平均值分别为8.63×106、7.83×106、8.49×106ind/ml,表层和底层丰度无显著差异,但均高于中层(P<0.05).相关性分析表明,浮游病毒丰度与异养细菌丰度、VBR呈显著正相关(P<0.01),与微微型真核浮游植物丰度呈显著负相关(P<0.05),与聚球藻、水深、水温、盐度、溶氧、叶绿素a浓度无明显相关性(P>0.05).  相似文献   
8.
The distributions of two swimming crabs endemic to the New Zealand region are described, mostly from material obtained at 118 of 2544 New Zealand Oceanographic Institute benthic stations sampled.

Nectocarcinus antarcticus (Jacquinot) was found within the geographic limits 34°S‐51°S and 166° E‐176° W, with concentrations around Cook Strait, the Chatham Rise, Foveaux Strait, and the Auckland Is. N. bennetti (Takeda & Miyake) occurred between 44° S and 53° S, and 165° E and 180°, most frequently in the south and west, on the ‘highs’ of the Campbell Plateau. Although the distributions overlap between 44° S and 51° S, and this overlap zone produced most of the available material, only one joint occurrence of the two species was noted. This apparent separation was not satisfactorily explained by any of the ecological factors recorded. The depth ranges of both species were broadly similar (0–550 m for TV. antarcticus, 20–474 m for JV. bennetti); both were most frequently obtained at depths less than 200 m. Both occurred primarily on the coarser sediment grades, though N. antarcticus occupied a broader range of grades than N. bennetti.

The size ranges of the two species were similar; carapace lengths were 8.0–62.0 mm for N. antarcticus and 5.8–68.0 mm for N. bennetti. The larger specimens of both species were found towards the southern limits of distribution. Larger specimens of N. antarcticus were absent from depths greater than 120 m; smaller N. antarcticus and all N. bennetti occurred throughout their respective depth ranges. Ovigerous N. antarcticus (smallest, 8.8 mm carapace length) were obtained at depths of 17–263 m from May to October; ovigerous N. bennetti (smallest 36.1 mm) were from depths of 150–183 m in May only.  相似文献   
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Month-to-month fluctuations in the abundance of bacteria and heterotrophic nanoflagellates (HNF) and bacterial production, as well as various chemical (nutrients, oxygen) and physical (salinity, temperature) parameters were analysed at a station located in the open middle Adriatic Sea during one decade (1997-2006). Being influenced by both coastal waters and open Adriatic circulation in the surface layer, and by the deep Adriatic water masses in the deep layers (100 m), this station is quite suitable for detecting the environmental changes occurring in the open Adriatic Sea with respect to the circulation of its water masses and their long-term changes and anomalies. Multivariate methods were used to identify seasonal and inter-annual changes of the investigated parameters, associating observed changes to the changes in Adriatic water masses and circulation regimes. The analyses showed that bacterial abundance and production were controlled by different water mass dynamics during 1997-2001 compared to 2002-2006 period, particularly noticeable in different seasonal patterns of biological parameters. The interplay between North Adriatic Dense Water (NAdDW) and Levantine Intermediate Water (LIW) resulted in a change in the available nutrients (NAdDW is poor in orthophosphates), and as a consequence different bacterial abundance and production. A few periods were examined in detail, such as 2004, when LIW inflow was particularly strong and was accompanied by an increase of bacterial and HNF abundances, as well as of bacterial production.  相似文献   
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