Abstract:

Aims Comparison of spatial patterns of clonal plant populations and soil variables has received little attention in ecological studies, although many papers implicitly assume that plant spatial distribution is controlled by soil variables acting at small scales. Our main aim was to investigate small-scale spatial cross-correlation between population variables of clonal plant species and soil available phosphorus.
Methods We investigated a ramet population of Potentilla reptans var. sericophylla in Dongling Mountain Area in Beijing to investigate the degree and scales of patchiness of soil available phosphorus and to determine spatial similarities between population variables and available phosphorus. Spatial soil and plant samples were collected in a plot of 336 cm× 96 cm. Semivariogram and cross-correlogram were applied to characterize spatial patterns.
Important findings Soil available phosphorus had clear patchy structure with the spatial autocorrelation range of 37.8 cm. Cross-correlation between measured variables of the ramet population of P. reptans var. sericophylla and soil available phosphorus was negatively significant at a lag interval of 75-110 cm, but not significant at a lag interval of 110-165 cm. There was significant positive correlation between soil available phosphorus and number of ramets and leaves and biomass of stolons at a lag interval <50 cm and for biomass of roots at a lag interval <30 cm. Resource sharing and selective placement of ramets in favorable micro-habitats may be important ecological strategies for Potentilla reptans var. sericophylla to exploit small-scale soil resources that are heterogeneously distributed.

Key words: soil available phosphorus, Potentilla reptans var. sericophylla, ramet population, small-scale, spatial heterogeneity, cross-correlation