Disturbances and non-living resource flows
Spatial flows were associated with disturbances, during which living
biomass was turned into detritus and used for the resource flows. More
specifically, every seven days (starting on day seven), we heated a
fixed volume of the community of each patch to 100 °C in a laboratory
oven to kill all organisms, thereby turning them into non-living
resources (i.e., local disturbance). Heating was done such that any loss
of water through evaporation was minimised, and replenished,
respectively. Resource flows were carried out at a fixed volume of 5.25
ml per patch (this represented 70 % of a small patch, 23.3 % of a
medium patch, and 14 % of a large patch). After cooling down, this
detritus part of patches that belonged to a connected meta-ecosystem was
transferred between the connected patches, while in the unconnected
controls the same volume was poured back to the patch where it
originated to control for the perturbation/mortality associated with
cross-ecosystem resource flows (‘resource retention’ in Fig. 1), yet
without having an actual cross-ecosystem flow. The loss of water through
evaporation was replenished to keep the volume of cultures consistent by
adding 1 ml of sterile protist medium to each patch after the third
disturbance event.