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Metacommunities are dynamic systems, but the influence of time independently of environmental change in their configuration has been rarely considered. In temporary ponds, strong temporal effects are expected to influence their metacommunity structure, even in relatively constant environments such as tropical habitats. We therefore expect that time as an independent factor could modulate tropical pond metacommunities, which would be also less affected by niche-related processes than by dispersal-related processes. In addition, good dispersers should be more environmentally structured than bad dispersers, which should be more spatially structured. Finally, the relevance of temporal effects should vary among organisms with different generation times. To test these hypotheses, we surveyed 30 temporary ponds along the dry tropical region of western Costa Rica and Nicaragua at three different moments of their hydroperiod: shortly after the infilling of the water bodies, at the middle of the hydroperiod and just before desiccation. We obtained data on 56 environmental variables and used geographic coordinates to build spatial variables (Moran Eigenvector Maps). We collected biological samples and estimated the specific abundance of phytoplankton, zooplankton and benthic invertebrates. To evaluate the relative role of environmental, spatial and temporal (sequential sampling season) effects for metacommunity organization, we used variation partitioning with distance-based redundancy analyses for each group of organisms. The inclusion of time in the analysis highlighted that pure temporal effects explained part of metacommunity variance in almost every group, being as important as spatial or even environmental effects for some groups of organisms. In contrast to the assumed low environmental constraints in tropical areas (i.e., high and stable temperatures), we found strong environmental effects. Passive dispersers were more influenced by environmental factors than active ones. We also found a positive relationship between the body size of the different groups of organisms and the magnitude of the temporal effects, interpreted as related to generation time. Finally, when analyzing each sampling period separately, we found differences in the relative role of environment and space at different sampling periods, showing that snapshot surveys may not be representative of highly dynamic metacommunities.

Objecte: Cada vegada més, les organitzacions estan més conscienciades que l’èxit empresarial s’aconsegueix amb el treball constant i enèrgic de tots els seus integrants. Aspectes com el compromís i la motivació son cabdals. Aquest article, fa referencia a la necessitat cada vegada més creixent d’utilitzar els canals de comunicació en línia per gestionar més eficaçment les relacions amb els empleats. Disseny/metodologia: Prenent com a base la teoria de la riquesa dels mitjans de comunicació, es fa una proposta per a examinarels factors que afecten en una comunicació eficaç, relacionant les senyals d’informació, la personalització, i la velocitat en dues situacions diferents. Aportacions i resultats: Aquest treball ofereix vuit propostes per tal d’estimular la investigació futura en els canals emergents. Limitacions: En l’estudi només es consideren dos canals de comunicació basats en internet: correu electrònic i missatgeria instantània. Implicacions pràctiques: Conèixer la percepció dels treballadors és fonamental per tal de millorar els processos comunicatius en organitzacions i institucions. Els resultats d’aquest recerca poden oferir una visió clara dels efectes de l’ús eficient de nous canals de comunicació. Implicacions socials: La capacitat dels nous dispositius mòbils amb connexió permanent online ha afavorit l’ús massiu de nous canals de comunicació. Conèixer els factors determinats que influeixen en la percepció dels usuaris sobre els nous canals, és un factor determinat en l’elecció dels mitjans de comunicació. Valor afegit: Tot i què es manifest l’ús intensiu dels nous canals de comunicació, són pocs els estudis que analitzin els efectes i repercussions del seu ús en organitzacions i institucions.

Zooplankton assemblages in neighboring ponds can show important spatial and temporal heterogeneity. Disentangling the influence of regional versus local factors, and of deterministic versus stochastic processes has been recently highlighted in the context of the metacommunity theory. In this study, we determined patterns of temporal and spatial variation in zooplankton diversity along one hydrological year in restored ponds of different hydroperiod and age. The following hypotheses regarding the assembling of species over time were tested: i) dispersal is not limited in our study system due to its small area and high exposure to dispersal vectors; ii) community dissimilarity among ponds increases with restoration age due to an increase in environmental heterogeneity and stronger niche-based assemblages;and iii) similarity increases with decreasing hydroperiod because hydroperiod is a strong selective force filtering out organisms with long life cycles. Our results confirmed dispersal as a homogenizing force and local factors as gaining importance with time of restoration. However, short hydroperiod ponds were highly dissimilar, maybe due to the environmental differences among these ponds, or to high stochasticity followed by priority effects under a weak selection pressure. By adding a temporal dimension to the study of zooplankton structuring, we could identify the first months after flooding as being crucial for species richness, especially in short hydroperiod ponds; and we detected differences in seasonal species richness related to hydroperiod and pond age.