Predicting competitive interactions between pioneer plant species by using plant traits

• Published in: Journal of vegetation science Vol. 8; no. 4; pp. 489 - 494
• Main Authors: Rosch, H, Rooyen, V, Theron, G.K
• Format: Journal Article
• Language: English
• Published: Oxford, UK Blackwell Publishing Ltd 01-08-1997; Opulus Press
• Subjects: Annuals; Arnold & De Wet; Average linear density; Biomass; biomass production; Competitive effect hierarchy; Deserts; Dimorphotheca sinuata; Ecological competition; growth; Leaf area; Life history strategy; Namaqualand; Phytometer; Pioneer species; plant colonization; plant communities; plant competition; Plant interaction; Plant roots; Plants; traits; South Africa
• ISSN: 1100-9233; 1654-1103
• DOI: 10.2307/3237200

A competitive effect hierarchy for 15 Namaqualand pioneer plant species was established by using the mean mass of the phytometer (Dimorphotheca sinuata) when grown in combination with itself and 14 other species. There were no clear groupings of species in the hierarchy. This competitive hierarchy (gradient) indicated which species are strong competitors (resulting in a low phytometer mass) with D. sinuata and which species are weak competitors (resulting in a high phytometer mass). Each plant species has a certain combination of plant traits which determines its life history strategy and competitive ability. Regressions of various plant traits (measured on plants grown singly) against phytometer biomass indicated which traits were significantly correlated. The traits, most being sizerelated, were: maximum shoot mass, total mass, stem mass, reproductive mass, leaf area, stem allocation, specific leaf area (SLA), vegetative height x diameter, leaf area ratio (LAR); and mean number of days to flower initiation. A forward stepwise multiple regression of the significant traits was used to determine an equation to predict competitive effect.