The Patagonian steppe consists of shrubs encircled by relatively dense stands of grasses; the areas between shrubs have scattered tussocks, interspersed with bare soil. This study investigates the seed bank and the establishment of a perennial grass, Bromus pictus, around shrubs and in the scattered-tussock patches, with special attention to root competition. About 20 times more seeds of B. pictus were found in the soil of the dense grass zone around shrubs than in the scattered-tussock patches. B. pictus seeds were placed in both types of patches, either with the natural level of below-ground competition present, or experimentally reduced by a fine mesh. Seedling survival and growth were reduced by root competition. Where root competition was experimentally reduced, the aerial protection afforded by the shrub increased the growth of seedlings. We conclude that root competition between adult plants and seedlings is mainly for soil water, and is greater near shrubs than in the scattered-tussock patches. Root competition from established plants is greater than the aerial protection afforded by shrubs, in the area close to shrubs.
Functional Ecology publishes original papers in organismal ecology, including physiological ecology, behavioural ecology and evolutionary ecology, and their implications for community and ecosystem patterns and processes. Papers may describe experimental, comparative or theoretical studies on any type of organism. Work that is purely descriptive, or that focuses on population dynamics (without investigation of the underlying factors influencing population dynamics) will not be accepted unless it sheds light on those specific areas mentioned above. Functional Ecology publishes standard papers, reviews, forum and perspective articles, in addition to special features which are collections of papers on a single theme. The journal is published six times a year. Further details are available at www.functionalecology.org. JSTOR provides a digital archive of the print version of Functional Ecology. The electronic version of Functional Ecology is available at http://www3.interscience.wiley.com/journal/117987963/home. Authorized users may be able to access the full text articles at this site.
The British Ecological Society is a welcoming and inclusive home for everyone interested in ecology. The Society was established in 1913 and has over 6,000 members worldwide, bringing people together across regional, national and global scales to advance ecological science. The BES's many activities include the publication of a range of scientific literature, including seven internationally renowned journals, the organisation and sponsorship of a wide variety of meetings, the funding of numerous grant schemes, education work and policy work.
This item is part of a JSTOR Collection.
For terms and use, please refer to our
Functional Ecology
© 1992 British Ecological Society