Skip Navigation

This Article
Right arrow Full Text Freely available
Right arrow FREE Full Text (PDF) Freely available
Right arrow Content Snapshot
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in ISI Web of Science
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Add to My Personal Archive
Right arrow Download to citation manager
Right arrow Search for citing articles in:
ISI Web of Science (12)
Right arrowRequest Permissions
Google Scholar
Right arrow Articles by WINKLER, E.
Right arrow Articles by STÖCKLIN, J.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by WINKLER, E.
Right arrow Articles by STÖCKLIN, J.
Agricola
Right arrow Articles by WINKLER, E.
Right arrow Articles by STÖCKLIN, J.
Social Bookmarking
Add to CiteULike   Add to Connotea   Add to Del.icio.us  
What's this?

Annals of Botany 89: 525-536, 2002
© 2002 Annals of Botany Company

Sexual and Vegetative Reproduction of Hieracium pilosella L. under Competition and Disturbance: a Grid-based Simulation Model

E. WINKLER*,1 and J. STÖCKLIN2

1UFZ-Centre for Environmental Research Leipzig-Halle, Department of Ecological Modelling, POB 500 135, D-04301 Leipzig, Germany and 2Universität Basel, Botanisches Institut, Schönbeinstr. 6, CH-4056 Basel, Switzerland

* For correspondence. E-mail ewi{at}oesa.ufz.de

Received: 21 August 2001; Returned for revision: 29 October 2001; Accepted: 18 January 2001.

We used a spatially explicit simulation model to examine the relative importance of vegetative and sexual reproduction in Hieracium pilosella L. Based on an understanding of the complex life cycle of this species and on data from in situ population dynamics in a calcareous grassland in NW Switzerland, we simulated growth and the relative contribution of clonal reproduction by stolons and reproduction by seeds across a gradient of increasing soil fertility. Competition by a clonal grass resulted in nearly complete exclusion of H. pilosella from the more fertile part of the simulation plot. Under low soil fertility, when grass could not survive, H. pilosella largely persisted by vegetatively produced rosettes. This pattern of a sharp separation of both species was shifted slightly in favour of H. pilosella by introducing random disturbances. Only by adding: (1) long-distance seed dispersal, and (2) facilitation of seedling establishment in the vicinity of grass tussocks in vegetation gaps was a more realistic representation of field observations realised, with rosettes of H. pilosella grown from seeds occasionally distributed within dense grass vegetation. Phenotypic plasticity of stolon length was a decisive factor for the maintenance of H. pilosella populations. We conclude that a mixed strategy of clonal growth and reproduction by seeds in H. pilosella is necessary to maintain populations of this species in the presence of high interspecific competition and a shortage of open space.

Key words: Clonal growth, competition, Hieracium pilosella, mouse-ear hawkweed, reproductive strategies, seed dispersal, sexual reproduction, spatially explicit model.


Add to CiteULike CiteULike   Add to Connotea Connotea   Add to Del.icio.us Del.icio.us    What's this?


This article has been cited by other articles:


Home page
 ANN BOT (LOND)Home page
T. TORIMARU and N. TOMARU
Fine-scale Clonal Structure and Diversity within Patches of a Clone-forming Dioecious Shrub, Ilex leucoclada (Aquifoliaceae)
Ann. Bot., January 2, 2005; 95(2): 295 - 304.
[Abstract] [Full Text] [PDF]


Disclaimer: Please note that abstracts for content published before 1996 were created through digital scanning and may therefore not exactly replicate the text of the original print issues. All efforts have been made to ensure accuracy, but the Publisher will not be held responsible for any remaining inaccuracies. If you require any further clarification, please contact our Customer Services Department.