engleski

Do invasive plants behave differently from native ones in the same environmental conditions, with respect to shares of Grime’s CSR strategies?

It is well known that disturbed areas are more prone to invasion by alien plant species than those with well preserved natural vegetation. Consequently, according to Grime’s CSR theory, it is expected that former areas will be overall dominated by ruderal species, while latter will be dominated by species with prevailing competitor strategy. Here, we tested whether this rule can be applied to invasive plants solely as well. We gathered available data on CSR strategies on invasive plants present in Croatia, and designated CSR strategies for those with missing information in the databases used. Surprisingly, it seems that invasive species do not follow the pattern expected based on native species. Because of various number of CSR types in different databases we harmonised all data to three basic types (C, S and R) with appropriate shares of values being equal to one when summed, for each particular species. Amongst native species in the Croatian flora, based on available data on 1452 species, C strategy was the most frequent one (49%) followed by 27% and 25% of ruderal and stress tolerant species, respectively. Amongst 57 invasive plant species, share of competitor species was the highest with as much as 58%, followed by 37% of ruderals and just 6% of stress tolerators. We analysed observed shares of CSR strategies per 10 km ETRS grid spatial units in the dependence on spatial habitat/landcover heterogeneity and Grime’s CSR type shares, as well as on basic environmental variables (e.g. elevation, precipitation, mean temperature). Although, in general, there were significant positive correlations between shares of CSR strategies amongst native and invasive plants, when analysed at 10 km spatial units, significant correlations between shares of native CSR types with environmental variables, were mostly not reflected within invasive plant species. Nevertheless it seems that among invasive plants, competitor strategy prevails, indicating that, among other plant functional traits, Grime’s CSR type can contribute to identification of alien plants that can be invasive as well

CSR strategies; ecology; invasive species

nije evidentirano