Metapopulation dynamics of a perennial plant, Succisa pratensis, in an agricultural landscape

Using both vegetation composition and sowing experiments we identified 94 occupied and 43 unoccupied, but suitable, habitat patches in a 7-km2 landscape. Local population dynamics were studied in permanent plots in five populations. Simulation results showed that the colonization and extinction dynamics of S. pratensis were slow with about one colonization or extinction per year and the time frame for the population system to attain equilibrium in a constant landscape was several thousands of years. Sensitivity analyses demonstrated that occasional long-distance dispersal had a large influence on population turnover rates whereas regular short-distance dispersal had little effect. Our model also allowed us to assess how demographic processes affect not only local population growth but also regional dynamics. Fecundity was more important, compared with growth and survival, in a metapopulation context than when considered only within populations. The effect of landscape development was examined through different land-use scenarios and suggested that S. pratensis only very slowly colonizes new habitats that are made available. Our results with S. pratensis in an agricultural landscape show that long-distance dispersal and colonization dynamics play an important role for the regional distribution in long-lived plants but that time lags, and thus the effect of landscape history, are also very important.