Clonal growth and plant species abundance.
OBJECTIVE
Both regional and local plant abundances are driven by species' dispersal capacities and their abilities to exploit new habitats and persist there. These processes are affected by clonal growth, which is difficult to evaluate and compare across large numbers of species. This study assessed the influence of clonal reproduction on local and regional abundances of a large set of species and compared the predictive power of morphologically defined traits of clonal growth with data on actual clonal growth from a botanical garden. The role of clonal growth was compared with the effects of seed reproduction, habitat requirements and growth, proxied both by LHS (leaf-height-seed) traits and by actual performance in the botanical garden.


METHODS
Morphological parameters of clonal growth, actual clonal reproduction in the garden and LHS traits (leaf-specific area - height - seed mass) were used as predictors of species abundance, both regional (number of species records in the Czech Republic) and local (mean species cover in vegetation records) for 836 perennial herbaceous species. Species differences in habitat requirements were accounted for by classifying the dataset by habitat type and also by using Ellenberg indicator values as covariates.


RESULTS
After habitat differences were accounted for, clonal growth parameters explained an important part of variation in species abundance, both at regional and at local levels. At both levels, both greater vegetative growth in cultivation and greater lateral expansion trait values were correlated with higher abundance. Seed reproduction had weaker effects, being positive at the regional level and negative at the local level.


CONCLUSIONS
Morphologically defined traits are predictive of species abundance, and it is concluded that simultaneous investigation of several such traits can help develop hypotheses on specific processes (e.g. avoidance of self-competition, support of offspring) potentially underlying clonal growth effects on abundance. Garden performance parameters provide a practical approach to assessing the roles of clonal growth morphological traits (and LHS traits) for large sets of species.
Institute of Botany, Academy of Science of the Czech Republic, CZ-252 43 Průhonice, Czech Republic Department of Botany, Faculty of Science, Charles University, Benátská 2, CZ-128 01 Praha 2, Czech Republic herben@site.cas.cz.
Tomáš
T
Herben
Botanical Garden of the Charles University, Na Slupi 16, CZ-128 01 Praha 2, Czech Republic.
Zuzana
Z
Nováková
Institute of Botany, Academy of Sciences of the Czech Republic, CZ-379 82 Třeboň, Czech Republic.
Jitka
J
Klimešová
D044822:Biodiversity; D002999:Clone Cells; D018153:Czech Republic; D008954:Models, Biological; D063245:Plant Development; D012100:Reproduction, Asexual; D013045:Species Specificity
Clonal plant growth; Ellenberg indicator values; LHS traits; botanical garden collections; lateral expansion; leaf-specific area; plant height; seed mass; seed reproduction; species abundance