Response of Sargassum Beds (Fucales) to Human Trampling: Reproductive, Morphological, and Biochemical Aspects

AbstractThis study explores the impact of human trampling on moss and lichen dominated communities of Maritime Antarctica. A simulation of trampling was performed on previously unaffected plots of different terricolous cryptogamic assemblages at Byers Peninsula, Livingston Island. The communities studied were: 1) a uniform moss carpet, 2) a heterogeneous moss assemblage composed of hummocks and turfs, and 3) a fellfield lichen community. All communities analysed were extremely sensitive but different denudation processes were observed. None of the plots maintained 50% of initial coverage after 200 pedestrian transits. Even very low trampling intensity resulted in disturbance at all plots. Sensitivities of the different communities were identified in order to formulate recommendations for minimizing the trampling impacts. In our study the lichen dominated community on dry exposed soils exhibited the lowest resistance to trampling. For moss communities, lower resistance was found in peat soils with higher water content and biomass. With the current trend of increasing human presence in Antarctica, we predict that the cumulative impacts of trampling over future decades will adversely affect all types of moss and lichen communities.

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Effects of human trampling on the sub-Antarctic vegetation of Macquarie Island

Polar Record ◽

10.1017/s003224740002427x ◽

1994 ◽

Vol 30 (174) ◽

pp. 207-220 ◽

Cited By ~ 22

Author(s):

J. J. Scott ◽

J. B. Kirkpatrick

Keyword(s):

Bulk Density ◽

Extreme Environments ◽

Soil Bulk Density ◽

Common Species ◽

Environmental Damage ◽

Track Width ◽

Macquarie Island ◽

The Past ◽

Human Trampling ◽

Short Section

AbstractThe effects of trampling on six types of vegetation and their underlying soils were investigated on sub-Antarctic Macquarie Island. One hundred and fifty foot-passes per year for at least the past 10 years have occurred on a typical 6-km stretch of walking track on the island's upland plateau. Trampling favours vascular plants including exotics, especially Poa annua, while bryophytes and lichens are more common in undisturbed vegetation. The abundance of 19 of the 39 most common species appears to be affected by trampling. Track width is positively correlated with exposure and wet soils, and trampling increases the soil bulk density of the track. The contrast between the soil bulk density of the trampled and untrampled soils increases with increasing exposure. While present environmental damage is within an acceptable range over the majority of the island, the extreme environments are likely to suffer unacceptable levels of damage if increased usage occurs with more tourism or expansion of scientific and related activities. This is demonstrated by the diversion of a short section of plateau track in an atypically heavily used area; the diversion sustained substantial damage after 890 foot-passes during a 15-month period.

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