Small‐scale spatial dynamics of plant species in a grassland community over six years

Abstract

Abstract. In a species‐rich mountain grassland in the Krkonosse Mts., Czechoslovakia, data from four permanent plots of 50 cm x 50 cm were recorded annually from 1985 to 1990 to study the spatial dynamics of the species. Plots were divided into 15 x 15 subplots and the number of vegetative units of all plants within each subplot was determined. There was not much net change at the plot level, but the subplots were very dynamic. Two aspects of the spatial dynamics of the species were followed: (1) persistence, i.e. the tendency of the species to remain in the same subplot, and (2) long‐distance spreading, i.e. movement to subplots beyond the immediate neighbourhood. Species differed widely in their persistence and longdistance spreading and were classified into mobility types: long‐range guerrilla, short‐range guerrilla, phalanx and 'sitting’. The mobility types were, to a certain extent, correlated with the growth form of plants, but some species of one growth form showed different types of small‐scale dynamics and some species with different growth forms had the same spatial dynamics.

Why do we need permanent plots in the study of long‐term vegetation dynamics?

“…Herben et al 1993). In these studies, one seeks for 'replacement rules' (species B is always locally replaced by species A) which might be further investigated by growth and competition experiments.…”

Effect of cattle activities on gap colonization in mountain pastures

“…species is thus not particularly different in the gap and in the closed surrounding vegetation where the turnover is high (HERBEN et al 1993, KLIMEŠ 1999, OTSUS & ZOBEL 2002. Differences between gaps and intact vegetation are rather in the species type than in their turnover (see below)…”

Chance, Variation and the Nature of Causality in Ecological Communities

“…Dynamics are obviously orders of magnitude slower than in bacterial communities but, interestingly, long-term observations have revealed patchy dynamics of grassland species that are reminiscent of those of the bacterial patches in petri dishes. In grasslands at the slopes of the Krkonoše mountains in the Czech Republic, species form patches that change position all the time because individuals die and are replaced by other species at one location while they appear at locations nearby as a result of clonal expansion or germination (Herben et al 1993a). The replacements of species are largely random and to some degree intransitive and thus resemble the "balanced chasing" described above Herben et al 1993b).…”