| 摘要: |
| 于1994年4-11月在东太平洋铁锰结核勘探区，随向阳红09号船，采集了39个表层沉积物、12个上覆水和7个结核样。在现场用平板法测定了异养细菌和铁、锰细菌丰度，用稀释法（MPN法）测定硫酸盐还原菌丰度。在实验室对船上带回的异养细菌和锰细菌进一步纯化分离，进行了12项生化试验，参照伯杰氏手册第八版鉴定至属。为了探讨微生物在大洋成矿过程的作用，使用分光光度法，测定锰细菌对锰、铁离子的转化作用和不同培养温度对转化作用的影响。结果表明，在微生物丰度方面，沉积物中异养细菌的丰度在3-9500 cell/g；锰、铁细菌的丰度在1×100-×103 cell/g；硫酸盐还原细菌的丰度分布范围在0-4000 cell/g。在上覆水和结核样中各类细菌的丰度均较低，比沉积物样低1个数量级。在细菌的菌属组成与近海区相比存在一定的差异，特别是在革兰氏阳性菌的组成上微球菌占了绝对优势。在成矿作用方面，锰细菌对锰、铁氧化还原的实验结果表明，在好氧的条件下，锰细菌使可溶性的Mn2+氧化为Mn4+，其氧化速度与环境温度存在密切关系；锰细菌对铁的氧化速度比对锰的氧化速度来得快。在厌氧的培养条件下，锰细菌能将高价铁还原为低价铁，而且使培养液的pH明显降低。 |
| 关键词: 东太平洋 成矿作用 异养细菌 锰细菌 |
| DOI： |
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| 基金项目:国家自然科学基金资助项目，39170011号 |
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| A STUDY ON BACTERIAL ABUNDANCE AND ITS MINERALIZATION IN IRON-MANGANESE NODULE AREA OF TI-IE EASTERN PACIFIC OCEAN |
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SHI Jun-xian,CHEN Zhong-yuan,YANG Ji-fang,HU Xi-gang
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Second Institute of Oceanography, State Oceanic Administration, Hangzhou, 310012
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| Abstract: |
| A survey on bacterial abundance and its mineralization in iron-manganese nodule over the eastern Pacific Ocean was carried out on board R/V “Xiangyanghong 09" from April to November, 1994. During the cruise, 39 sacrificial sediment samples, 12 overlaying water samples and 7 iron-manganese nodule samples were collected. The abundance of heterotrophic bacteria and that of iron-manganese bacteria were determined on the basis of the plate-culture-counting method. The abundance of sulfate-reducing bacteria was measured on board using the MPN method. Taxonomy of the bacteria was determined through a series of biochemical tests following isolation and purification of the bacteria in the laboratory, according to “Borger’s Manual of Determinative Bacteriology, 8th”. In order to study the role of the bacteria on the mineralization iron and manganese and the effect of temperature, transformation of iron and manganese ions at different temperatures were measured using spectrophotometry; at the same time pH was monitored. The results show that the abundance of heterotrophic bacteria in the sacrificial sediments ranged from 3×100 to 9.5×103 cell/g; it is from 1×100 to ×103 cell/g for iron and manganese bacteria and 0 to 4×103 cell/g for the sulfate reducing bacteria. The abundance of the various bacteria in the overlaying water was an order of magnitude lower than in iron-manganese. The bacterial composition in the study area was different from that in offshore; particularly, Micrococcus predominated among the Gram-positive bacteria. The results of oxidation-reduction of iron ions and manganese ions by bacteria show that under aerobic condition Mn2+4+
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| Key words: Eastern Pacific Ocean, Mineralization, Heterotrophyc bacteria, Manganese bacteria |
