Ai. Englonger et J. Podani, A new approach in evaluating the efficiency of macromorphological description of reed (Phragmites australis (Cav.) Trin. ex Steudel) stands, FLORA, 196(5), 2001, pp. 381-389
Newly proposed macromorphological characters and methods are presented and
tested by canonical variates analysis and principal components analysis. Di
viding ramets into "growth sections" avoids the problem that, depending on
the environment and age, reed ramets are composed of different numbers of n
odes. If the objective is to examine selected features of as many reed stan
ds as possible, new characters are useful. The length and location of the l
ongest internode provide stronger separation between different reed stands
than the use of an increased number of internodes. To monitor the morpholog
ical changes of the same reed ramets in situ during the whole vegetation pe
riod, we proposed to measure the distances between the tops of leaf sheaths
. Reed ramets need not be cut and disassembled, because between-leaf sheath
distances are highly correlated with the lengths of internodes, and they e
xplain the strong separation of the different stands. Using our formula, th
ese distances can also be calculated, which provides opportunity for collec
ting further information from previous morphological data or for comparing
them with newly obtained data.