Invasive Species Compendium

Detailed coverage of invasive species threatening livelihoods and the environment worldwide

Abstract

Weed flora of arable peat in Selangor, Malaysia - quantitative and spatial pattern analyses.

Abstract

Collated data from the 1995-1996 floristic surveys of weeds of arable peat in Selangor district were analysed to assess composition and dominance, and spatial distribution pattern, based on quantitative and dispersion indices. Forty-eight weed species belonging to 19 families (of which 31 were broadleaves, 10 grasses and 7 sedges) were sampled; these made up 77, 8 and 15% of the total cover, respectively. The 10 most important species, in the order of dominance, were Fimbristylis acuminata, Murdannia nudiflora, Hedyotis corymbosa, Ageratum conyzoides, Asystasia gangetica, Cleome rutidosperma, Cyperus sphacelatus, Lindernia crustacea, Ludwigia hyssopifolia and Ludwigia perennis. Thirty-seven species displayed different degrees of aggregated pattern of spatial distribution, based on variance-to-mean ratios, Lloyds mean crowding or Lloyds patchiness indices. Other species were either random or regular in their spatial distribution.