汉阳两湖泊底泥酶活性和脂肪酸垂直分布特征

Preliminary Analysis on Vertical Distributing Characteristics of Enzyme Activities and Fatty Acids in Sediments of Two Lakes in Hanyang District

酶活性和脂肪酸是富营养化湖泊底泥重要的生化指标。研究以武汉市汉阳地区两个湖泊为对象,测定了其中的酶活性(比色法)和脂肪酸(温和碱性甲酯化方法)。结果表明:酸性磷酸酶活性在表层和亚表层没有显著性差异(p>0.05),而脲酶表层酶活性显著高于亚表层,甚至在有些位点差异极显著(p<0.0005);饱和直链脂肪酸(碳原子数<19)占总脂肪酸比例为40.40%～47.85%,多不饱和脂肪酸比例为18.21%～25.08%,表层和亚表层之间差异不明显(p>0.05);单不饱和脂肪酸占总脂肪酸比例为19.60%～29.31%,饱和直链脂肪酸(碳原子数>19)占总脂肪酸比例为6.47%～14.28%,表层和亚表层之间差异显著(p<0.05)。碳原子数≥C24的长链脂肪酸比例很低,为1.57%～3.60%。上述研究结果在一定程度上获得了富营养化浅水湖泊底泥中酶活性和脂肪酸在垂直空间上的分布特征。

Both enzyme activities and fatty acids are important biochemistry parameters in eutrophic lake sediments. Two lakes in Hanyang District, Wuhan were chosen as research objects, with colorimetry for analysis of enzymatic activities and mild alkaline methanolysis method for analysis of fatty acids, surface and subsurface sediments were measured. Results showed that acidic phosphatase activities between the two layers sediments had no significant difference, while surface urease activities were significantly or extremely significantly higher than which in the subsurface sediments. The proportions of saturated straight chain and polyunsaturated fatty acids were 40.40%-47.85% and 18.21%N25.08% respectively. Differences between surface and subsurface layer were not significant. Proportions of the monounsaturated and saturated straight chain fatty acids were 19.60%-29.31% and 6.47%-14.28% respectively. Differences between surface and subsurface layer were significant. Long chain fatty acids proportions of 1.57%-3.60% were low. The results uncovered the vertical distributing characteristics of enzyme activities and fatty acids in the eutrophic shallow lake sediments to some extent.