Forest management conditioning ground ant community structure and composition in temperate conifer forests in the Pyrenees Mountains

Arnan X., Gracia M., Comas L., Retana J. (2009) Forest management conditioning ground ant community structure and composition in temperate conifer forests in the Pyrenees Mountains. Forest Ecology and Management. 258: 51-59.
Link
Doi: 10.1016/j.foreco.2009.03.029

Abstract:

The search for indicators to monitor management impact on biodiversity is a crucial question because management practices promote changes in community structure and composition of different animal groups. This study explores the effect of widely conducted management practices (forest logging and livestock) in Pinus uncinata forests in the Pyrenees range (NE Spain) on the structure and composition of ground ant communities compared to those of old-growth stands. Forest structure clearly differed in stands with different forest managements. These stands managed for different uses also showed marked differences in structure and composition of ground ant communities. There was a great dominance of a single species, Formica lugubris, which accounted for 99% of ants collected in pitfall traps. Rarefaction curves indicated that species richness was highest in old-growth stands and lowest in even-aged ones, with woodland pasture stands showing an intermediate value. Classification methods allowed us to identify two groups of species: six species related to old-growth plots and three species (including F. lugubris) associated to managed stands. Habitat structure played an important role in determining the structure of ant communities: forests with high tree density but low basal area were the most favourable forest type for F. lugubris, while the abundance of the remaining ant species was negatively affected by the abundance of F. lugubris and by tree cover. © 2009.

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L’edat de les oliveres monumentals i singulars del Montsià.

Martínez-Vilalta J, Claramunt B, Arnan X, Estorach M, Poyatos R (2009) L’edat de les oliveres monumentals i singulars del Montsià. Raïls 25: 208-221.

Climatic drivers of hemispheric asymmetry in global patterns of ant species richness

Dunn R.R., Agosti D., Andersen A.N., Arnan X., Bruhl C.A., Cerdá X., Ellison A.M., Fisher B.L., Fitzpatrick M.C., Gibb H., Gotelli N.J., Gove A.D., Guenard B., Janda M., Kaspari M., Laurent E.J., Lessard J.-P., Longino J.T., Majer J.D., Menke S.B., McGlynn T.P., Parr C.L., Philpott S.M., Pfeiffer M., Retana J., Suarez A.V., Vasconcelos H.L., Weiser M.D., Sanders N.J. (2009) Climatic drivers of hemispheric asymmetry in global patterns of ant species richness. Ecology Letters. 12: 324-333.
Link
Doi: 10.1111/j.1461-0248.2009.01291.x

Abstract:

Although many taxa show a latitudinal gradient in richness, the relationship between latitude and species richness is often asymmetrical between the northern and southern hemispheres. Here we examine the latitudinal pattern of species richness across 1003 local ant assemblages. We find latitudinal asymmetry, with southern hemisphere sites being more diverse than northern hemisphere sites. Most of this asymmetry could be explained statistically by differences in contemporary climate. Local ant species richness was positively associated with temperature, but negatively (although weakly) associated with temperature range and precipitation. After contemporary climate was accounted for, a modest difference in diversity between hemispheres persisted, suggesting that factors other than contemporary climate contributed to the hemispherical asymmetry. The most parsimonious explanation for this remaining asymmetry is that greater climate change since the Eocene in the northern than in the southern hemisphere has led to more extinctions in the northern hemisphere with consequent effects on local ant species richness. © 2009 Blackwell Publishing Ltd/CNRS.

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