关键词: 群落演替, 马尾松人工纯林, 松材线虫病, 干扰模式, 林分结构

Abstract: For the culture mode of over-winter sheds (OWS), water samples were collected fromLitopenaeus vannamei culture ponds aiming to investigate the variation of microbial community structure, dominant bacterial species and environmental factors in the pond water in the middle and late stage of culture. The results showed that the water temperature increased from 20.6   ℃ to 26.5   ℃ after building OWS, which was suitable for the growth of shrimp. The amount of heterotrophic bacteria in the water was between 5.1×10⁴ and 2.95×10⁵ cfu·mL^-1 in the middle and late stage of culture. The structure of microbial community was relatively stable, and the number of dominant bacteria increased.Psychrobacter andSulfitobacter were the dominant bacteria, whileFlavobacteria andHyphomicrobium appeared after building OWS. Additionally, the RDA analysis showed that nitrite nitrogen, nitrate nitrogen and temperature were the major physical and chemical factors influencing the abundance and distribution of microbial communities. The results indicate that aquaculture environment could be kept relatively stable after OWS building, and the regulation of nitrogen concentration is very important in the middle and late stage of culture. Therefore, we suggested that probiotics should be used before and after building OWS in order to promote and stabilize ecological advantage of beneficial bacteria, and regulate bacterial community structure and ecological function.

Key words: pure Pinus massoniana plantation, Burasphelenchus xylophilus, stand structure, community succession., intervention pattern