Micro-meiofauna morphofunctional traits linked to trophic activity

While the important role of algae and bacteria is widely recognized in freshwater ecosystems, that of minute grazers, despite their high abundance, remains poorly understood. By their consumption of microalgae, their role in the microbial loop, and even their movements in the biofilm, they improve the rejuvenation of this type of ecosystem and have an important function in the connectivity of interfaces. In this study, we approach diversity issues from the standpoint of morphofunctional traits of periphytic micro-meiofauna. We collected and coded morphofunctional characteristics for several micro-meiofauna species from the literature and from our own observations to create a micro-meiofauna morphofunctional traits database inspired by the model of Usseglio-Polatera et al. (Freshw Biol 43(2):175-205, 2001). This new database of traits may represent an interesting collaborative tool which could be used to improve knowledge on micro-meiofauna and their functional role in the biofilm. We used the information to explore variations in functional traits related to trophic activity among micro-meiofauna communities. Counting data were acquired from biofilms grown in a hypereutrophic pond (Aquitaine, France) in winter and in spring. Community-weighted means (CWM) computed using the database and counting data revealed Spring food web was more complex than winter food web.