Zs. P. Komáromy szerk.: Studia Botanica Hungarica 12. 1977 (Budapest, 1977)

Szujkóné Lacza, Júlia; Sen, Subir: Distribution, diversity and equitability of the Hungarian species of Gentiana and Gentianella ciliata L. (Gentianaceae)

We have, however, considered diversity to represent the distribution of individuals of a species per factor gradient. It is, therefore, interesting to find out the factor which produces maximum and minimum diversity and equitability in the four species. Further, it may be useful to determine the differences between the effect of different factors on a particular species. MATERIAL AND METHODS Our observations are based on the dried specimens of the Herbarium Budapest (H. B. ). All the herbarium sheets studied have been cited according to the alphabethical order of the locality. The name of the exact location is followed by the name of the district in bracket. The district name is followed by that of region and geographical area (given under inverted coma). The name of the geographical area is followed by the collector's name which in its turn is followed by the date of collection. All the details are given in the same language in which they are written in the herbarium sheets. The languages are German, Hungarian, Latin, Roumanian and Slovakian. In those cases where there are two collectors, their names are connected by the Latin et (= and). The names given after putting a coma after the date of collection indicate those of subsequent collectors collecting the same species from the same locality, while those after a semicolon represent the name of a new locality. In some cases we could find only the geographical area and not the exact location of a specimen, so we have indicated only the geographical area under inverted coma. There are some sheets in which the names of exact location and geographical area are given but not that of the district. In such cases the name of the geographical area has been put in brackets. Further information regarding the plants, e. g. habitat, altitude and basic nature of stone, if any, have not been given for brevity. However, they have been used in calculating diversity except the basic nature of stone. We have collected all the data available in the herbarium sheets for calculating diversity, equitability and frequency of flowering. For diversity we have followed the SHANNON - WEAVER'S model (1963). GREENE (1975) have compaired the six diversity indices and suggested the advantages and disadvantages of the different indices

. in biological sciences. Equitability has been calculated by following M. LLOYD and R. J. GHELARDI (1964). First we have calculated diversity and equitability of each of the four species in relation to different environmental factor gradient and flowering time. Then we determined the proportion of equitability of each species in relation to the highest number of each factor gradient. This is the relative H' equitability = E' = (where C= number of categories). log. max. c. At last, we have made an attempt to find out the correlation, if any, between a factor gradient and the pattern of distribution of the species (after KULLBACH 1959).