Search results for " Tuberarietea guttatae"
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A stochastic model of seed dispersal pattern to assess seed predation by ants in annual dry grasslands
2005
A combined field experiment and modelling approach has been used to provide evidence that ants may be responsible for an observed lower patchiness and higher plant diversity in the neighbourhood of ant nests, within Mediterranean dry grasslands belonging to the phytosociological class Tuberarietea guttatae. The hypothesis was that seeds occurring in clumps may have an higher probability to be harvested than seeds having a scattered distribution. In order to test this hypothesis, four analysis steps have been performed. First, the seed productivity and dispersal pattern was recorded for four plant species found, either more abundant beside the ant nests (Tuberaria guttata, Euphorbia exigua) …
Plant-ant interaction in xerophilous ephemeral vegetation of S.E. Sardinia.
2003
Frequency and abundance of annual plants have been measured in 40 square plots, 0.36 m2 each, settled in an area of approximately 5 ha at the foothill of the Sarrabus massif, in S.E. Sardinia. 20 plots were randomly distributed at less than 5 m from the ant nests, further 20 at more than 30 m from the ants nests. The results showed a significantly lower plant density next to the ant nests, together with an higher species richness. Far from the nests, plots resulted dominated by relatively few species with a patchy distribution, while next to the nests the distribution of frequencies resulted more homogeneous. It is suggested that harvesting ants may contribute to the small-scale regulation …