作 者 ：Li Liang-Qian
期 刊 ：植物分类学报 1988年 3期
Keywords:Sino-Himalayan flora, Aconitum, Geographical distribution, Endemic plant,
Abstract:
The geographical distribution of Aconitum in the Sino-Himalayan subregion is
analysed in the present paper on the basis of taxonomy and relationship between the infrage-
neric taxa. Asaresult, some conclusions may be arrived as follows:
1. The Sino-Himalayan subregion is the frequency centre and the diversity centre of the
genus. For analysis, the distribution area of the genus are assigned to three floristic regions,
viz. 1) the East-Asian floristic region, consisting of the Sino-Himalayan subregion and Sino-
Japanese subregion, 2) the Euro-Siberian region and 3) the North-American region (Table 1).
In the East-Asian floristic region, the Sino-Himalayan subregion comprises 3 subgenera, about
5 sections, about 13 series and nearly 180 species. However, the Sino-Japanese subregion has
only 2 subgenera, 2 sections. 6 series and about 50 species. The Euro-Siberian region has 2
subgenera, 2 sections, about 9 series and nearly 70 species. The North-American region has
2 subgenera (one of the 2 subgenera has only 1 species), 1 section, 1-2 series and about 26
species. Obviously, the Sino-Himalayan subregion is the richest in taxa.
2. The Sino-Himalayan subregion is not only the preservation centre of the primitive
groups and species, but also an actively differentiating region. Largely in the Sino-Himalayan
subregion occurs primitive or more primitive tava in the genus, such as Sect. Fletcherum, Sect.
Alatosperum and Sect. Sinaconitum, Ser. Tangutica and Ser. Brunnea etc.: A fletcherianum,
A. novoluridum, A. chrysotricum, A. brevicalcaratum, A. polycarpus, A. nagarum, A. tanguti-
cum, A. hookeri, A. naviculare, A. violaceum, etc. On the other hand, the Sino-Himalayan
subregion also has the most or relatively advanced taxa, represented by the annual monotypic
subgenus Gymnaconitum, A. spiripetalum, A. hamatipetalum and A. bulbitiferum ect. About
50 infraspecific taxa occur in the subregion. For example, A. hemsleyanum has 8 varities, A.
franchetii has varities and A. nagarum 1 varity and 2 forms, ect.
3. In the region under discussion the genus Aconitum shows remarkable endemism.
The endemic taxa include 3 sections (Sect. Fletcherum, Sect. Alatosperum and Sect. Sina-
conitum), 3 series (Ser. Brevicalcarata, Ser. Crassiflora and Ser. Bullatifolia) and nearly 150
species, among which primitive and advanced ones are both present.
4. The pattern of geographical distribution of the genus Aconitum shows remarkable
relationship between latitude and altitude. The majority of species of this genus prefer habi-
tats with a cool and more or less constantly moist climate. In the Sino-Japanese subregion, with
a higher latitude, the genus has an altitude range of 500-1500 m, whereas in the Sino-Hima-
layan subregion the range is 2900-5000 m.
To sum up, the Sino-Himalayan subregion is the diversity centre, the frequency centre, the
differentiation centre, the preservation centre of the primitive taxa and the centre of endemism
of the genus Aconitum, and its development in this subregion has probably been accelerated
by the lift of the Himalayas and the complicated environmental conditions.