Abstract
Species dissimilarity (beta diversity) primarily reflects the spatio–temporal changes in the species composition of a plant community. The correlations between β diversity and environmental factors and spatial distance can be used to explain the magnitudes of environmental filtering and dispersal. However, little is known about the relative roles and importance of neutral and niche-related factors in the assemblage of plant communities with different life forms in deserts. We found that in desert ecosystems, the β diversity of herbaceous plants was the highest, followed by that of shrubs and trees. The changes in the β diversity of herbs and shrubs had stronger correlations with the environment, indicating that community aggregation was strongly affected by niche processes. The soil water content and salt content were the key environmental factors affecting species distributions of the herb and shrub layers, respectively. Spatial distance explained a larger amount of the variation in tree composition, indicating that dispersal limitation was the main factor affecting the construction of the tree layer community. The results suggest that different life forms may determine the association between organisms and the environment. These findings suggest that the spatial patterns of plant community species in the Ebinur Lake desert ecosystem are the result of the combined effects of environmental filtering and dispersal limitation.
Highlights
Community assembly is important to the coexistence of species and the maintenance of biodiversity and is one of the hottest issues in contemporary community ecology [1,2,3,4,5]
We found that the dissimilarity index of different types of plant species in the desert ecosystem increased with the increase in geographical distance, similar to previous research [22] that showed a decrease in the similarity index of species with the increase in geographical distance, or the dissimilarity index of species increased with the increase in geographical distance
This study showed that the mechanism of species diversity and community assembly in the desert ecosystem was dispersal limitation in the tree layer (pure spatial variables had a higher contribution rate (13.55%) than that of environmental filtering (11.56%), while environmental filtering had a higher explanatory power for Characteristics and driving mechanisms of species beta diversity species composition variation in the shrub and herb layers
Summary
Community assembly is important to the coexistence of species and the maintenance of biodiversity and is one of the hottest issues in contemporary community ecology [1,2,3,4,5]. For more than a century, ecologists have been trying to clearly explain how community assembly maintains biodiversity, with niche theory and neutral theory being two outstanding conceptual frameworks. Whether stochastic processes or deterministic processes are more important in community assembly and whether their relative contributions are stable are questions that have attracted much scholarly attention over time. The relative contributions of each type of process will change according to different scales, species groups, and ecosystem types [5,6,7]. In order to understand the mechanisms of community assembly more accurately, it is necessary to consider the roles of multiple factors in the discussion of their effects.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
