Small wetlands provide crucial ecosystem services but are facing widespread loss and degradation. At present, small wetland complexes provide an alternative avenue for conservation; we used a dataset to illustrate how zeta diversity can be assessed in a small wetland complex. The small wetland complex studied consisted of nine hydrologically connected ponds, and all the ponds were connected by narrow ditches. Data collected included the composition of both zooplankton and phytoplankton communities, water physicochemical parameters, and hydrological connectivity. Two ways in which connectivity affects biodiversity, dispersal filtration (path distance-controlled biological diffusion) and environmental filtration (environment-selected species), were quantified. As a result, (1) 46 zooplankton and 119 phytoplankton species were identified, with species richness distribution significantly affected by water properties (explained variances of 68% and 39%, respectively), reflecting significant environmental filtration, and (2) both zooplankton and phytoplankton showed zeta diversity distance decay (p < 0.001), reflecting significant dispersal filtration, and (3) relatively rare species dominated community turnover, in which environmental filtration was far stronger than dispersal filtration. Overall, the small wetland complex in this study was characterized by hydrological connectivity, which not only allowed moderate biological connectivity but also promoted the coexistence of diverse habitats and communities. We emphasize the applicability of zeta diversity for assessing small wetland complexes, further demonstrating the value of small wetland complexes in promoting biodiversity such as species richness and species turnover.

Understanding how biodiversity loss alters flowering patterns in plant communities is crucial for predicting species coexistence, community dynamics, and ecosystem functioning under global change. Using phenological records from 2017 to 2023 within a 12-year species removal experiment in a Tibetan alpine meadow, we examined responses of early-, mid-, and late-flowering functional groups and changes in community flowering-date synchrony and temporal stability. Species removal tended to advance first flowering but more consistently delayed last flowering and extended flowering duration, with differential responses among flowering functional groups leading to contrasting changes in community flowering-date synchrony: forb removal decreased synchrony, whereas grass and dominant-sedge removal increased synchrony. Forb removal, grass removal, and proportional thinning also reduced the temporal stability of community first and last flowering dates. Declining species richness and lower richness stability were associated with increased phenological divergence among flowering functional groups, which predicted 88% and 85% of the variation in community-wide dispersion of first and last flowering dates, respectively. Greater dispersion was associated with lower temporal stability only for first flowering. These findings suggest a temporal-niche pathway through which species loss may reorganize community flowering phenology and help predict long-term changes in floral resource availability and ecosystem functioning in alpine meadows.