How do water regime and clipping influence wetland plant establishment from seed banks and subsequent reproduction?
In: Aquatic Botany. Elsevier Science: Tokyo; Oxford; New York; London; Amsterdam. ISSN 0304-3770; e-ISSN 1879-1522, more
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| Keywords |
Behaviour > Feeding behaviour > Grazing
Behaviour > Reproductive behaviour
Population characteristics > Biomass
Water bodies > Inland waters > Wetlands
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| Abstract |
This paper presents the findings from an experiment designed to address whether grazing in interaction with water regime influences wetland plant establishment and reproduction, using clipping to simulate grazing. The experiment was a randomised complete block design in a set of outdoor tanks in which communities establishing from seed banks were assessed. For wetland plant species from the Northern Tablelands of NSW, Australia, water regime primarily determined which species germinated from the seed bank to form a wetland community. The subsequent total reproductive output was largely controlled by clipping and its influence on growth of species. Three different responses to clipping were observed. For some species, e.g. Limosella australis R. Br., Centipeda minima (L.) A. Braun & Asch., and Lythrum salicaria L., both biomass and production of reproductive units increased following clipping. Other species did not replace biomass lost to clipping and produced fewer reproductive units compared to unclipped populations (e.g. Vallisneria gigantea Graeb., Myriophyllum variifolium Hook. f.). A third response, shown by Cyperus sanguinolentus Vahl., was an increase in the number of reproductive units produced together with a decrease in biomass as a result of clipping. These clipping-mediated changes in reproductive output have the potential for altering the structure and dynamics of the extant wetland vegetation and soil seed bank, with implications for species conservation and weed management. |
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