Effect of propagule pressure on recovery of a California grassland after an extreme disturbance
نویسندگان
چکیده
Methods: We monitored plant community composition in paired grassland patches that were initially dominated by native or exotic grasses at eight sites. We followed recovery of native and exotic grassland species over time, starting in a record drought year prior to an intense fire, and then for 3 yrwithmore typical rainfall patterns after the fire. Additionally, we compared seed rain of native and exotic species across native and exotic patches, quantifying how seed rain influenced species abundance in the following year. Multivariate and regression analyses were used to assess the potential homogenization of the landscape.
منابع مشابه
Effects of vegetative propagule pressure on the establishment of an introduced clonal plant, Hydrocotyle vulgaris
Some introduced clonal plants spread mainly by vegetative (clonal) propagules due to the absence of sexual reproduction in the introduced range. Propagule pressure (i.e. total number of propagules) may affect the establishment and thus invasion success of introduced clonal plants, and such effects may also depend on habitat conditions. A greenhouse experiment with an introduced plant, Hydrocoty...
متن کاملInvasion, competitive dominance, and resource use by exotic and native California grassland species.
The dynamics of invasive species may depend on their abilities to compete for resources and exploit disturbances relative to the abilities of native species. We test this hypothesis and explore its implications for the restoration of native ecosystems in one of the most dramatic ecological invasions worldwide, the replacement of native perennial grasses by exotic annual grasses and forbs in 9.2...
متن کاملThe relative importance of the species pool, productivity and disturbance in regulating grassland plant species richness: a field experiment
1. Ecologists have generally focused on how species interactions and available niches control species richness. However, the number of species in the regional species pool may also control richness. Moreover, the relative influence of the species pool and species interactions on plant richness may change along productivity and disturbance gradients. 2. We test the hypothesis that many species f...
متن کاملAssessing the relative importance of disturbance, herbivory, diversity, and propagule pressure in exotic plant invasion
The current rate of invasive species introductions is unprecedented, and the dramatic impacts of exotic invasive plants on community and ecosystem properties have been well documented. Despite the pressing management implications, the mechanisms that control exotic plant invasion remain poorly understood. Several factors, such as disturbance, propagule pressure, species diversity, and herbivory...
متن کاملEcological resistance, seed density and their interactions determine patterns of invasion in a California coastal grassland.
Relatively little experimental evidence is available regarding how ecological resistance and propagule density interact in their effects on the establishment of invasive exotic species. We examined the independent and interactive effects of neighbour cover (biotic resistance), winter vs. spring water addition (abiotic resistance) and seed density on the invasion of the European perennial grass ...
متن کامل