Abstract: The mechanism underlying community assembly is a core content in the fields of biogeography and community ecology. Understanding community assembly is of great significance for biodiversity conservation. The theory of metacommunity incorporates spatial dynamics into community ecology, elucidating how ecological processes drive community construction at local and regional scales. Metacommunities originated from plant community ecology and have been extensively studied in large animal and plant communities. In recent years, they have also begun to be applied to small- and micro -animal communities. Nematodes are the most diverse and abundant animals, capable of predicting environmental changes at multiple scales, and are model organisms for the study of community assembly theory. We introduced the main content of the theory of nematode assemblages, and reviewed research progress on nematode assemblages in marine, freshwater, and soil habitats. We further proposed to optimize nematode classification methods and enrich the research scale of nematode assemblages in the future, aiming to improve the research content of nematode assemblages and further promote the research and development of community assembly mechanisms in community ecology.

Key words: nematode community assembly, environmental filtering, dispersal limitation, biotic interaction, ecological drift