Mediterranean endorheic wetlands are strongly affected by local meteorological events, so they undergo frequent unpredictable disturbances, such as episodes of high salinity or desiccation. In this context, salinity and temperature may be crucial for determining the structure of zooplankton communities and regional biodiversity, since they may trigger the hatching of egg bank in different ways. The goal of this study is to assess the combined role of these two variables on the zooplankton assemblage emerging from the egg bank. We hypothesize that temperature and salinity affect the community structure in a non-linear way, that is, both factors interact and modify the magnitude of their effects. We performed a laboratory factorial design where the same sediment was incubated under different thermal and salinity conditions, reducing the potential effects of other possible confusion factors. Community structure was described by measuring cumulative abundances, species composition, richness, and diversity. Our results showed that the community structure was strongly determined by salinity at all experimental temperatures. In contrast, the magnitude of the temperature effect depended on salinity. The high variability among replicates when salinity and temperature increased suggests that climate change might lead to unpredictable patterns of the community emerging from the egg bank.

Temporary Mediterranean wetlands are characterized by both intra and interannual variations in their environmental conditions. These inherent fluctuations in limnological features affect the seasonal variation in the structure and dynamics of the aquatic communities. In this study, we hypothesized that zooplankton community is coupled to seasonal changes of the environmental variables along the hydroperiod. To get this purpose, the study was focused in monitoring, by collecting monthly samples during an annual period, seven temporary Mediterranean ponds located in the south-eastern region of the Iberian Peninsula (Alto Guadalquivir region, Andalusia). The relationships between zooplankton community and the different limnological variables were analyzed based on two approaches: a Spearman correlation analysis and a correspondence canonical analysis (CCA). The results have shown that chlorophyll-a concentration, Secchi depth, total nitrogen concentration, wetland area and depth were the variables with a greater influence on the zooplankton community, explaining the zooplankton species replacement. Moreover, optima and tolerance of the zooplankton species were obtained from the position of species within CCA diagram, allowing the separation of different groups of zooplankton along the hydroperiod. We finally highlight that the monitoring of zooplankton community and environmental conditions are necessary to evaluate how theses singular and endangered aquatic ecosystems will be affected by anthropogenic activities in the future.

The macroinvertebrate community, physical–chemical water variables and hydromorphological indices were studied in the Turón River (Málaga, Southern Spain). Our study aims to improve the knowledge of the most influential environmental factors at different spatial and temporal scales in Mediterranean rivers, in order to establish better management of Mediterranean river ecosystems. To this end, in this work, seasonal sampling was carried out for one year to evaluate the effect of the characteristics of the drainage basin (i.e., geology, topography, land use) on the macroinvertebrate community. To this end, the environmental variables of the catchment basins were evaluated at three different scales: (i) watershed level, (ii) valley segment level and (iii) local level. The results showed that 13 environmental variables, 3 at the watershed scale, 5 at the valley segment scale and 5 at the local scale, influenced the macroinvertebrate community. Land use is the main explanatory variable at the watershed scale, while stream channel curvature is the most common variable at the valley segment scale, and the habitat assessment index is the variable with the strongest influence at the local scale. The influence of different spatial scales presented a seasonal variation. During spring, autumn and winter, the watershed scale exhibited the highest resolution (adjusted R² = 0.20–0.29), while in summer, the local scale became the most significant in explaining the presence of macroinvertebrate taxa (adjusted R² = 0.17). The obtained results emphasize the significance of temporal and spatial scales in Mediterranean rivers for adequate river ecosystem management.

Mediterranean wetlands are suitable ecosystems for studying metacommunity theory, since they are isolated ecosystems within a land matrix with well-established limits, often with watersheds destined for agricultural uses. The zooplankton community of wetlands in agricultural landscapes is the result of processes that operate in a different multiscale context. We selected 24 ponds in Alto Guadalquivir region (SE Spain) with different local environmental variables (biological, limnological and land uses). The zooplankton community of the wetlands under study consists of a total of 60 species: 38 branchiopods and 22 copepods. This community (total, branchiopods and copepods) was analysed through two different and complementary metacommunity approaches. The pattern approach determines the species distribution along environmental gradients, and the mechanistic approach considers the involved processes, such as environmental control and dispersal limitation. The results indicated a nested metacommunity, in which five limnological variables, three land uses and six spatial variables are the main drivers that explain zooplankton distribution in these wetlands. In conclusion, species sorting and dispersal processes play a role in the structuring of the zooplankton metacommunity. This conclusion has implications for the development of adequate management policies on Mediterranean wetland protection and diversity conservation in agricultural contexts.

Intrinsic ecological characteristics of Mediterranean wetlands make them excellent sites for studying biodiversity, but these wetlands have been studied much less frequently than temperate lakes. The invertebrates that inhabit them, and zooplankton specifically, play important roles in these wetlands. We compared the ability of taxon- and size-based analyses of the zooplankton community to predict the influence of environmental variables. We sampled environmental variables and zooplankton at 7 Mediterranean wetlands in the Iberian Peninsula (southern Spain) monthly along 1 hydroperiod cycle (2009–2010). We used 3 arrays for classifying the zooplankton community: 1) species occurring in >5% of the samples, 2) coarse-level taxa easily identified by a nonexpert (large branchiopods, small branchiopods, calanoid copepods, cyclopoid copepods, and harpacticoid copepods), and 3) 4 body-size classes (10 mm in length). We used permutational analysis of variance (PERMANOVA) and canonical correspondence analysis (CCA) to test our hypotheses. Communities differed significantly among wetlands, and body size (55.8% of explained variance) was more useful than taxonomic composition (common taxa: 24.4%, coarse-level taxa: 26.5% of explained variance) for rapid assessment of the influence of the environmental variables on zooplankton community in temporary wetlands.

This study investigated the mechanisms determining macrophyte species composition in 23 Andalusian Mediterranean mountain wetlands (southern Spain). We employed a methodology combining two approaches: a pattern-based approach utilizing Elements of Metacommunity Structure (EMS) and a mechanistic approach involving Redundancy Analysis (RDA) and variance partitioning. This allowed us to identify the relevance of interactions between environmental and spatial factors. Data collection in these wetlands included macrophyte samples and physicochemical variables, alongside spatial variables generated using Moran’s Eigenvector Maps (MEMs). To refine the analysis of metacommunity structuring, the species matrix was partitioned based on macrophyte dispersal strategy (charophytes by spores and macrophyte vascular plants by seeds). Our results reveal that the macrophyte metacommunity in these wetlands exhibits quasi-clumped species loss for the total community, while charophytes and vascular plants showed quasi-random species loss. In conclusion, this study demonstrates that macrophyte communities in Mediterranean mountain wetlands do not follow a simple species replacement pattern. Instead, they are organized in a quasi-nested pattern, strongly shaped by environmental filters and, to a lesser extent, by spatial connectivity, with a prominent role for random processes. Understanding these mechanisms is crucial for predicting species responses to environmental changes and for designing effective conservation strategies within these vulnerable ecosystems.