Shrub encroachment control by browsing: Targeting the right demographic process

摘要: Exploring key demographic parameters for establishment and growth of shrub populations enables us to identify the life stages or plant organs that browsers need consume effectively influence population dynamics. However, there is a lack concrete knowledge on how browsing can efficiently meet this goal. We therefore tested impact different levels intensity parameter (survival juveniles) major colonizing species (broom, Cytisus scoparius) in order control growth, designed management strategy focused target stage. Three intensities, representing pertinent practices, were simulated juveniles (2 years old) broom population. Juvenile plants either left untouched (control treatment; n = 126) had 50% 90% their total edible stem biomass removed “light-intensity browsing” (n = 127) “high-intensity (n = 77) treatments, respectively. Survival fecundity data collected over 6 years. Standard matrix modeling was used analyze changes rate (λ), results 6.34 (control), 2.26 (light browsing) 0.85 (heavy browsing). Therefore, natural expansion may be slowed by light even reversed heavy (λ < 1). This multi-year survey confirms focusing an efficient controlling dominance. Shrub strategies should early-growth-stage repeat at same several achieve cumulative effects.