Data for: Ecosystem connectivity and configuration can mediate instability at a distance in metaecosystems

Ecosystems are connected by flows of nutrients and organisms. Changes to connectivity and nutrient enrichment may destabilise ecosystem dynamics far from the nutrient source.
We used gradostats to examine the effects of trophic connectivity (movement of consumers and producers) versus nutrient-only connectivity on the dynamics of Daphnia pulex (consumers) and algae (resources) in two metaecosystem configurations (linear vs. dendritic).
We found that Daphnia peak population size and instability (coefficient of variation; CV) increased as distance from the nutrient input increased, but these effects were lower in metaecosystems connected by all trophic levels compared to nutrient-only connected systems and/or in dendritic compared to linear systems.
We examined the effects of trophic connectivity (i.e. both trophic levels move rather than one or the other) using a generic model to qualitatively assess whether the expectations align with the ecosystem dynamics we observed.
Analysis of ..., Our gradostat flasks contained simple communities of the water flea Daphnia pulex consuming a mix of three algal species (Pseudokirchneriella subcapitata, Scenedesmus quadricauda, Ankistrodesmus falcatus). This experiment employed a 2x2x2 factorial design to test the importance of ecosystem trophic connectivity (a treatment considering movement of medium only vs. movement of media, phytoplankton and Daphnia between flasks) and metaecosystem configuration (linear or dendritic) on the stability of Daphnia populations and algal communities with two levels of enriched medium input (regular and phosphorus-enriched). Four replicates of this whole design were established, for a total of 32 metaecosystems, run in 9 blocks due to time and space constraints. Each metaecosystem consisted of four “nodes” of 500 mL Erlenmeyer flasks with a foam stopper to allow for gas exchange (128 flasks total), seeded initially with 100 mL algal mix (total average algal density of 2.22 x106 +/- 1.3x104 cells/mL) ..., , # Data for: Ecosystem connectivity and configuration can mediate instability at a distance in metaecosystems

[https://doi.org/10.5061/dryad.p2ngf1vxk](https://doi.org/10.5061/dryad.p2ngf1vxk)

These data describe *Daphnia pulex* and algal metacommunity dynamics in experimental gradostats (flasks connected by the movement of nutrients and organisms in linear and dendritic configurations). Each node was sampled every two days for 30 days to record population densities and estimate their total size. Peak population size and population coefficient of variation was calculated for each flask, and across metacommunities. We also write a mathematical model to describe these dynamics.

## Description of the data and file structure

Four data sets are included. The first (dapalg1.csv) is the raw data file with the recorded daily numbers of daphnia, and each species of algae within each experimental flask, as well as our two major outcome variables (peak and CV), and these are the data that were ...