摘要
对 1 994— 1 995年南海中部时间系列沉积物捕获器收集的微体生物壳体进行了氨基酸与糖类分析。结果表明 ,微体生物壳体中含有的氨基酸与糖类物质大致与颗粒物全样相当 ,其氨基酸与糖类组成基本保持了活体浮游生物的特征 ,而与颗粒物全样有所不同 ,推测氨基酸与糖类物质一是作为壳体本身的组成部分存在于壳体中 ;二是被包裹在有孔虫房室及放射虫、硅藻壳体纹饰或筛孔中 ,因而可以很好保存。上述结果表明生物壳体本身也是有机质从海洋表层向下输送的良好载体 ,而且生物体内氨基酸与糖类组成的原生信息可以很好地保存于壳体内 ,这对于利用壳体中的生物标志物来追索原生的有机物来源、演化及其它环境信息具有重要意义。
It is commonly believed that microfossils in marine sediment have very low content of organic matter such as amino acids.Planktonic tests collected by time series sediment trap in the South China Sea were analyzed.Results show that their concentrations of amino acids,amino sugars and carbohydrates are 7.5,0.14 and 1.7 mg·g -1 (dry weight) for 250—1000μm part, and 32.0,0.4 and 5.3mg·g -1 (dry weight) for 63—250μm part,respectively.Cenerally,the content of these organic mixtures in settling planktonic test in similar to that in bulk particulate matter.The spectra of amino acids,amino sugars and carbohydrates in settling planktonic shells are very similar to those in living plankton,suggesting that proteins and polysaccharides preserved in the shells are as fresh as those in living plankton.The proteins and polysaccharides may act as efficient templates for shell formation, and some organic matrix may actually be entrapped in chambers of forminifera or micro holes of diatom,radiolaria,so the organic mixtures are affected little by bacteria decomposition.These results show that settling planktonic shells might act as very important carriers for the vertical transportation of organic carbon,at least in water column shallower that CCD and opal lysocline.On the other hand,since planktonic shells can preserve more intact and fresh organic matrix than total particulate matter,to analyze organic composition of planktoinc shells in sediments instead of bulk sediment may be more helpful to understand sources,environmental conditions and biogeochemical process in water column.
出处
《海洋与湖沼》
CAS
CSCD
北大核心
2000年第6期596-603,共8页
Oceanologia Et Limnologia Sinica
基金
中德合作及国家自然科学基金资助项目!4 97762 97号
关键词
氨基酸
糖类物质
南海
微体生物壳体
氨基糖
Settling planktonic tests\ \ Amino acids\ \ Carbohydrates\ \ Sediment trap\ \ South China |
