CLONAL VARIATION IN POPULATIONS OF RANUNCULUS-REPENS

A computer simulation model is developed to examine the relationship between the population flux of ramets, the recruitment of seedlings and genet diversity in populations of Ranunculus repens in a North Wales pasture. The study is based on a continuous monitoring of the flux of ramets and recruitment of seedlings in eight populations over a period of 4 years. A simple flow diagram, which describes the life‐cycle of R. repens and which incorporates the field census data, is used as the basis for a series of computer simulations. The computer model simulates the actual flux of ramets in each of the eight populations and, assuming no selection between families, is used to follow the fates of ramets and families of ramets. Comparisons between the numbers of families of ramets in the real and simulated populations provide little evidence for selection between families of ramets or against new seedling recruits. With no selection the number of original families present within a population declines at an approximately exponential rate and the contribution made by these families to the total genet diversity of the population rapidly becomes subordinate to the role of new seedling inputs. It is suggested that although the contribution of seedlings to maintaining the total number of individuals, Nη, in populations of plants which spread clonally may be very small, the occasional establishment of seedlings may nevertheless play a significant role in determining the number of clones or genets, N. Copyright © 1979, Wiley Blackwell. All rights reserved