Université de Neuchâtel

Horizontal Distribution Patterns of Testate Amoebae (Protozoa) in a Sphagnum magellanicum Carpet

Mitchell, Edward A. D. ; Borcard, Daniel ; Buttler, Alexandre J. ; Grosvernier, Philippe ; Gilbert, Daniel ; Gobat, Jean-Michel

In: Microbial Ecology, 2000, vol. 39, no. 4, p. 290-300

The distribution of soil microorganisms is generally believed to be patchy and to reflect habitat heterogeneity. Despite this general rule, the amount of existing data on species distribution patterns is scarce. Testate amoebae (Protozoa; Rhizopoda) are an important component of soil microbial communities and are increasingly used in ecological and paleoecological studies of...

Université de Neuchâtel

Relating niche and spatial overlap at the community level

Hofer, Ulrich ; Bersier, Louis-Félix ; Borcard, Daniel

In: Oikos, 2004, vol. 106, no. 2, p. 366-376

If interspecific competition is a strong structuring force of communities, ecologically similar species should tend to have spatial ranges at local scale that do not overlap. Experimental testing of this hypothesis becomes impracticable with large communities. One possibility to tackle this issue is a correlational approach, by comparing the matrix of niche overlap with that of spatial overlap....

Université de Neuchâtel

Ecotones and gradient as determinants of herpetofaunal community structure in the primary forest of Mount Kupe, Cameroon

Hofer, Ulrich ; Bersier, Louis-Félix ; Borcard, Daniel

In: Journal of Tropical Ecology, 2000, vol. 16, no. 4, p. 517-533

The relative effects of the elevational gradient and of environmental discontinuities (ecotones) on the structure of a herpetofaunal assemblage in a tropical upland forest were contrasted by means of canonical correspondence analysis. Qualitative descriptors were used to define the elevational positions of the ecotones of interest, namely transitions in forest type and presence/absence of water...

Université de Neuchâtel

Spatial Organization of a Herpetofauna on an Elevational Gradient Revealed by Null Model Tests

Hofer, Ulrich ; Bersier, Louis-Félix ; Borcard, Daniel

In: Ecology, 1999, vol. 80, no. 3, p. 976-988

Five null model tests were applied to the herpetofaunal assemblage on the western slope of Mount Kupe, Cameroon. Based on the pattern of species range boundaries and abundances along the primary forest elevational gradient, ranging from 900 to 2000 m, the relative importance of interspecific competition and ecotones in structuring the assemblage was assessed. Tests were run for (1) all species,...