Austroeupatorium inulifolium invasion alters soil seed bank in anthropogenic grassland: a case study from Sri Lanka

<em>Austroeupatorium inulifolium </em>is aggressively invading many land use types in the Knuckles Conservation Area (KCA) in Sri Lanka. The <em>Cymbopogon nardus</em> dominated grasslands, often demarcated by native forests, are the most vulnerable.  The present study quanti...

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Bibliographic Details
Main Authors: I. P. K. Piyasinghe, J. Gunatilake, H. M. S. P. Madawala
Format: Article
Language:English
Published: Faculty of Science, University of Peradeniya, Sri Lanka 2017-06-01
Series:Ceylon Journal of Science
Subjects:
Online Access:https://cjs.sljol.info/articles/7432
Description
Summary:<em>Austroeupatorium inulifolium </em>is aggressively invading many land use types in the Knuckles Conservation Area (KCA) in Sri Lanka. The <em>Cymbopogon nardus</em> dominated grasslands, often demarcated by native forests, are the most vulnerable.  The present study quantified the soil seed bank and the standing vegetation of these highly invaded grasslands. Forest-grassland edge (FGE) has been identified as the starting point for this invasion, and therefore sampling was carried out twice at different distances from the FGE towards the grassland (0, 10 and 30 m). The soil seed bank showed high seasonality with higher abundance and richness in the wet season than in the dry season. Interestingly, the dry season soil seed bank was dominated by native species (78%) while the wet season seed bank was dominated marginally by exotics (52%), with the highest contribution from <em>Austroeupatorium</em>. The scarcity of tree seedlings was noticed during the study. <em>Austroeupatorium</em> and tree seeds showed decreasing trends from the FGE towards the invasive grassland, and were evident in the seed bank as well as in the standing vegetation. Despite similar trends, the soil seed bank and the standing vegetation of invasive grasslands showed low similarity in terms of richness and abundance due to the dominance of a single species.  The results suggest that <em>Austroeupatorium</em> invasion has the potential to alter the existing vegetation in these highly degraded grasslands and influences their succession over time.
ISSN:2513-2814
2513-230X