三江并流区澜沧江干流捕食线虫真菌的水陆分布模式探究

为研究三江并流区澜沧江干流水、陆生境中的捕食线虫真菌（Nematode-Trapping Fungi NTF）多样性分布差异，在该区域布设9个采样区对NTF进行了调查，并分析了NTF在澜沧江流域不同空间尺度下的水陆分布模式。每个样区设置水、陆对称采样点各5个，每个采样点用5点法采集水、陆样品各1份，共采集90份样品。采用单孢子挑离法获得NTF纯培养，结合形态学和分子生物学方法鉴定物种。共获得2属13种76株NTF，其中陆生土壤中检出2属11种49株，水体底泥中检出1属6种27株。结果显示，NTF物种组成在三江并流区澜沧江干流水、陆生境间存在较大差异，具有水陆异质性分布模式，干流陆地上具有比水生环境中更高的物种检出率和物种多样性；此外，与之前对澜沧江支流NTF的水陆分布研究结果相比，NTF在干流上水陆分布差异比支流更大，表明在流域生态系统中，NTF的监测结果同时也能反映不同空间尺度下的环境异质性，以流域为研究单元，以NTF为研究对象，可能更有助于了解微生物的空间分布格局。

Terrestrial and Aquatic Distribution Patterns of Nematode-trapping Fungi in the Mainstream of Lancang River of the Three Parallel Rivers Area

This study aims to investigate the diversity of nematode-trapping fungi (NTF) between terrestrial and aquatic environments in the main stream of the Lancang River Basin in Yunnan Province, and will help to understand the distribution patterns of microorganisms between terrestrial and aquatic environments in the Lancang River watershed at different spatial scales. Nine sampling areas were systematically selected. 5 terrestrial and 5 aquatic soil sample points were collected at each sampling area, 5-point method was used to classify each sampling point. A total of 90 samples were collected. Pure culture of NTF was obtained by single spore isolation, and the species were identified by morphological and molecular biological techniques. A total of 76 strains, 13 species belong to 2 genera were isolated from the main stream of Lancang River, including 49 strains, 11 species belong to 2 genera from terrestrial soil, and 27 strains, 6 species belong to 1 genus from aquatic sediment. The results showed that there was a heterogeneity distribution pattern between terrestrial and aquatic environments in the main stream of the Lancang River, the species detection rate and species diversity in the terrestrial environment of the main stream of the Lancang River were higher than those in the aquatic environment. Meanwhile, compared with previous study about the distribution of NTF in the tributaries of the Lancang River, there was a stronger difference of the distribution of NTF between terrestrial and aquatic in the main stream than in the tributary. The results showed that microbial monitoring results can also reflect environmental heterogeneity at different spatial scales in watershed ecosystem, and it is more helpful to understand the spatial distribution pattern of microbial species by taking the watershed as the research area and NTF as the research object.