汾河太原段硅藻种间关联和相关分析

Interspecies Association Analysis of Diatom in Taiyuan Segment of Fenhe River

通过现场采样、室内鉴定对来自汾河太原段水体8个采样点的22个优势硅藻种进行了关联和相关分析。结果表明,它们之中正相关的种对占66.23%,根据Spearman秩相关系数计算结果,22个种可被划分为4个生态种组,分别指示不同的环境条件。扭曲小环藻(Cyclotella comta)、锉刀布纹藻(Gyrosigma scalproides)等是寡污带的指示生物,耐污性差,生长于清洁的环境中;眼斑小环藻(Cyclotella ocellata)、小异极藻(Gomphonema parvulum)等为β-中污带的指示生物,但耐污力差,是轻污水体的良好指示生物;短线脆杆藻(Fragilaria brevistriata)、适宜舟形藻(Navicula accomda)等主要分布在α-中污带和β-中污带,耐污力强,生态幅广;谷皮菱形藻(Nitzschia palea)、纤细异极藻(Gomphonema gracile)等主要分布于多污带,指示水体受有机污染严重。

Algae are the major producers in the freshwater ecosystem. Previous studies have shown that the structure and species composition of an algae community is directly related to the quality of water in its environment. Different kinds of pollutants have correspondingly different influences on the species compositions, populations and structures of an algae community. Species with positive association have similar biological characteristics and demand similar habitats, the interspecies relationship is one of the important characteristics of biology community, through the research of interspecies relationship, the spatial reciprocity of different species can be objectively feedbacked. In this paper, X^2 test with 2×2 contingency table, Ochiai index, Jaccard index, Dice index and Spearman correlation coefficients were used to analyze the interspecific association of 22 diatom dominant species from 8 different sites along a 19 kilometer long segment of the Fenhe River around the City of Taiyuan. Three different samples were collected from each site. The results showed that the association of species was mainly positive. The 22 diatom dominant species were divided into 4 ecological groups by Spearman constellation diagram, and indicated the water qualities of clean zone, β-mesosaprobic, α-mesosaprobic and oligosaprobic separately. And the relationships among species-pairs were of significant difference in different types of ecological groups. Among the three correlations indices, the Jaccard index was lower than other indices, but three correlation indices indicated the same results.