Spatial distribution of Tephrocactus aoracanthus (Lem.) Lem. in relation to shrubs in the hyperarid regions of west-central Argentina
Article first published online: 12 APR 2012
© 2012 The Authors. Austral Ecology © 2012 Ecological Society of Australia
Volume 38, Issue 2, pages 131–138, April 2013
How to Cite
ALMIRÓN, M. and MARTÍNEZ CARRETERO, E. (2013), Spatial distribution of Tephrocactus aoracanthus (Lem.) Lem. in relation to shrubs in the hyperarid regions of west-central Argentina. Austral Ecology, 38: 131–138. doi: 10.1111/j.1442-9993.2012.02385.x
- Issue published online: 21 MAR 2013
- Article first published online: 12 APR 2012
- Accepted for publication March 2012.
- environmental heterogeneity;
- intra/interspecific association;
- Wiegand–Moloney's O(r) statistics
The spatial intraspecific and interspecific distribution of Tephrocactus aoracanthus (Lem.) Lem. was studied using univariate and bivariate point pattern analysis, at landscape scale in four different physiographic units and at microscale in terms of the shrubs found in those units. The influence of shrubs on photosynthetically active radiation and on soil temperature under their canopies was analysed. Results show a high environmental variability in light and temperature under shrubs that generally has no influence on the distribution of T. aoracanthus. Apparently, this cactus has great ability to adapt to different conditions of both photosynthetically active radiation and temperature. However, intraspecific distribution was highly clustered in all physiographic units, independently of bushes. Possibly, the mode of seed dispersal and the rooting of cladodes at small scale are the main processes that determine the strong intraspecific clustering of T. aoracanthus.