天然水体中生物膜及悬浮颗粒物的元素含量研究

应用一种简便的生物膜采样装置 ,分别于 1999年 7和 10月在北京颐和园昆明湖水体中采集生物膜、悬浮颗粒物和湖水样品 ,研究了天然水体中生物膜及悬浮颗粒物的元素含量 .用光学显微镜和扫描电子显微镜 (SEM)观察生物膜的形态和结构表明 ,生物膜内存在着棒形或球形的细菌、藻类、有机碎屑、原生动物和甲壳类动物等 .对生物膜样品的重量分析表明 ,在实验期间 ,随着生长时间的延长 ,生物膜样品的干重明显增加 .生长 78d时 ,1m水深处的生物膜样品干重可达 5 .19mg·cm-2 .用电感藕合等离子体发射光谱仪 (ICP AES)测定了生物膜、悬浮颗粒物和湖水中元素含量 .结果表明 ,实验期间生物膜中元素含量高于悬浮颗粒物 .同一时间、相同地点、不同水层深度生物膜样品中的元素含量无明显的规律性 .在 3个采样点 ,1及 1.5m水深处的生物膜样品中Ca、Mg、K、Na、Al、Fe和S的含量基本相近 ,Mn、Sr、Ti、P、La、Co、Cu、Pb、Li、Ni、B、Ce、V、Be和Cr的含量存在差异 .生长时间越长 ,生物膜样品的元素含量相对较高

Element contents of biofilm and suspended particulate in natural aquatic ecosystem

The element contents of biofilms and suspended particulates in the natural aquatic ecosystem were studied, and the samples were collected in Kunming Lake of the Summer Palace in July and October 1999. The biofilm samples were observed through microscope and scanning electron microscope. Various inhabitants such as sessile bacteria, algae, and protozoa existed in the biofilms. The dry weights of biofilms increased with the longer growth period. The dry weight of biofilm at 1 m depth of water reached to 5.19 mg.cm-2 after the growth time of 78 days. The element contents in biofilm, suspended particulate, and lake water were analyzed by ICP-AES, and the results indicated that the element contents in biofilms were higher than those in the particulates. There was not an evident trend in the element contents of biofilms at the different water depth in the same site and growth time. At three sampling sites, the contents of Ca, Mg, K, Na, Al, Fe, and S in the biofilm samples were similar between 1 m and 1.5 m depth of water, but the contents of Mn, Sr, Ti, P, La, Co, Cu, Pb, Li, Ni, B, Ce, V, Be, and Cr were different in the biofilm samples of 1 m and 1.5 m depth of water. The element contents of biofilms increased with the longer growth time.