TY  - JOUR
AU  - Maurizio Mencuccini
AU  - Jordi Martinez-Vilalta
AU  - Josep Piñol
AU  - Lasse Loepfe
AU  - Mireia Burnat
AU  - Xavier Alvarez
AU  - Juan Camacho
AU  - Debora Gil
PY  - 2010//
TI  - A quantitative and statistically robust method for the determination of xylem conduit spatial distribution
T2  - AJB
JO  - American Journal of Botany
SP  - 1247
EP  - 1259
VL  - 97
IS  - 8
KW  - Geyer
KW  - hydraulic conductivity
KW  - point pattern analysis
KW  - Ripley
KW  - Spatstat
KW  - vessel clusters
KW  - xylem anatomy
KW  - xylem network
N2  - Premise of the study: Because of their limited length, xylem conduits need to connect to each other to maintain water transport from roots to leaves. Conduit spatial distribution in a cross section plays an important role in aiding this connectivity. While indices of conduit spatial distribution already exist, they are not well defined statistically. * Methods: We used point pattern analysis to derive new spatial indices. One hundred and five cross-sectional images from different species were transformed into binary images. The resulting point patterns, based on the locations of the conduit centers-of-area, were analyzed to determine whether they departed from randomness. Conduit distribution was then modeled using a spatially explicit stochastic model. * Key results: The presence of conduit randomness, uniformity, or aggregation depended on the spatial scale of the analysis. The large majority of the images showed patterns significantly different from randomness at least at one spatial scale. A strong phylogenetic signal was detected in the spatial variables. * Conclusions: Conduit spatial arrangement has been largely conserved during evolution, especially at small spatial scales. Species in which conduits were aggregated in clusters had a lower conduit density compared to those with uniform distribution. Statistically sound spatial indices must be employed as an aid in the characterization of distributional patterns across species and in models of xylem water transport. Point pattern analysis is a very useful tool in identifying spatial patterns.
UR  - http://www.amjbot.org/content/97/8/1247.short
L1  - http://refbase.cvc.uab.es/files/MMG2010.pdf
UR  - http://dx.doi.org/10.3732/ajb.0900289
N1  - IAM;
ID  - Maurizio Mencuccini2010
ER  -