Treatment-based Markov chain models clarify mechanisms of invasion in an invaded grassland community
- 28 October 2009
- journal article
- Published by The Royal Society in Proceedings Of The Royal Society B-Biological Sciences
- Vol. 277 (1681), 539-547
- https://doi.org/10.1098/rspb.2009.1564
Abstract
What are the relative roles of mechanisms underlying plant responses in grassland communities invaded by both plants and mammals? What type of community can we expect in the future given current or novel conditions? We address these questions by comparing Markov chain community models among treatments from a field experiment on invasive species on Robinson Crusoe Island, Chile. Because of seed dispersal, grazing and disturbance, we predicted that the exotic European rabbit (Oryctolagus cuniculus) facilitates epizoochorous exotic plants (plants with seeds that stick to the skin an animal) at the expense of native plants. To test our hypothesis, we crossed rabbit exclosure treatments with disturbance treatments, and sampled the plant community in permanent plots over 3 years. We then estimated Markov chain model transition probabilities and found significant differences among treatments. As hypothesized, this modelling revealed that exotic plants survive better in disturbed areas, while natives prefer no rabbits or disturbance. Surprisingly, rabbits negatively affect epizoochorous plants. Markov chain dynamics indicate that an overall replacement of native plants by exotic plants is underway. Using a treatment-based approach to multi-species Markov chain models allowed us to examine the changes in the importance of mechanisms in response to experimental impacts on communities.Keywords
This publication has 36 references indexed in Scilit:
- Dynamic patterns and ecological impacts of declining ocean pH in a high-resolution multi-year datasetProceedings of the National Academy of Sciences, 2008
- Rapid shifts in the chemical composition of aspen forests: an introduced herbivore as an agent of natural selectionBiological Invasions, 2006
- Markov chain models predict the consequences of experimental extinctionsEcology Letters, 2004
- Late quaternary vegetation dynamics and human impact on Alexander Selkirk Island, ChileJournal of Biogeography, 2003
- The Vegetation of Robinson Crusoe Island (Isla Masatierra), Juan Fernandez Archipelago, ChilePacific Science, 2002
- Exploring spatial vegetation dynamics using logistic regression and a multinomial logit modelJournal of Applied Ecology, 2001
- Causes of species diversity differences: a comparative analysis of Markov modelsEcology Letters, 2001
- Effects of Introduced Plants and Animals on Island Vegetation: Examples from Galápagos ArchipelagoConservation Biology, 1989
- Demographic Consequences of Larval Development Mode: Planktotrophy vs. Lecithotrophy in Streblospio BenedictiEcology, 1987
- Transition Probabilities for a ForestNature, 1970