| Geographical
aspects and plant diversity of the Hengduan Mountains and the
Shuiluo Valley
Hengduan Mountains –
The Hengduan Mountains in SW China are located between 26°
and 34° north latitude and 96° and 104° east
longitude, making up a total area of 790’000 square
kilometres. They belong to the earth’s richest and
most threatened reservoirs of plant and animal live, spanning
SW Sichuan, NW Yunnan and part of eastern Tibet. Referring
to the topography they are also called “High Mountain
and Deep Gorge Region“.
Mountains reach altitudes of 7500 m while stream networks
and rivers, including the Mekong, Salween and Yangtze, dissect
innumerable small and large valleys. Southwest monsoon from
the Indian Ocean strongly influences the climate resulting
in a rainy season from June to October and allowing tropical
vegetation in the valleys to reach almost 29° north
latitude.
Botany
– Botanically,
it is one of the richest temperate area in the world with
approximately 12’000 species of vascular plants. The
area harbours 47 strictly endemic genera. A high amount of
endemic species is proposed in several articles but the number
is not specified. A National Geographic article reports 3500
endemic species for the Hengduan Mountain region.
Medicinal
plants – The
Hengduan Mountains are a rich source of traditional Chinese
and Tibetan medicinal plants.The bulk of those is still harvested
from the wild. Since several medicinal species of the area
are over-exploited and threatened, models of sustainable collection
or cultivation are urgently needed. Until recently logging
was one of the most important income sources in the area and
only 10-20% of the original forest cover survived. Recently,
the Chinese government applied a policy to preserve the remaining
primary forests and banned lumbering in the meantime.
Shuiluo
Valley – The
Shuiluo Valley is situated in the south of Hengduan Mountains
(ca. 28° N; 101° E), at an elevation of 2000-6000
m. The Shuiluo River, a tributary of the Yangtze, is approximately
80 km long. The climate is characterized by seasonal monsoon
from June to October with an annual rainfall mean of about
1000 mm. The vegetation types of the Shuiluo Valley can be
divided into a dry to semi-dry valley bottom, open bush lands,
subtropical evergreen broad-leaved, temperate and cold-temperate
conifer forests, alpine bush woods with a timberline at about
4000 m, and alpine vegetation.
For a panoramic view of the
characteristic vegetation zones click on the links
below (large files!).
| Vegetation
types |
Altitude |
Characteristic
species |
Semi-dry
valley bottom
|
2000-2400
m |
Shrubs:
Jasminum nudiflorum, Osteomeles schwerinae,
Pistacia weinmannifolia, Rumex
hastatus, Myrsine africana |
Mixed
pine and oak woodlands
|
2400-3500
m |
Trees:
Pinus yunnanensis, Acer paxii, Phyllanthus
emblica, Quercus spp.
Shrubs: Capparis subtenera, Morus acidosa,
Rhododendron cephalantum, R. chartophyllum,
Berberis spp.
Vines: Polygonum spp., Tetrastigma spp.,
Vitis spp. |
Mixed
coniferous forest and Rhododendron thickets
•
Pictures |
3500-4400
m |
Trees:
Abies delavayi, Larix potanini, Picea
likiangensis, Quercus dentata, Sorbus
vilmorini
Trees/shrubs: Juniperus squamata, Rhododendron
recurvum, R. taliense, Salix spp.
|
Alpine
vegetation
•
Pictures |
above
4400m |
Dwarf
shrubs: Cassiope selaginoides, Juniperus
squamata, Potentilla fruticosa, Rhododendron
spp., Salix spp. |
•
Cultural
diversity and social aspects
• back
to the overview
Used literature Boufford
D.E. and van Dijk P.P. 1999. South-Central China.
In Mittermeier R.A., Myers N., Robles G.P., and Mittermeier
C.G. (eds), Hotspots: Earth’s biologically richest
and most endangered terrestrial ecoregions. CEMEX,
Mexico: 338-351. Guan
K.Y., Zhou Z.K., Sun H., Fei Y., and Sun W.B. 1998. Highland
flowers of Yunnan. Yunnan Science and Technology
Press, Kunming. Handel-Mazzetti
H. 1921. Übersicht über die wichtigsten
Vegetationsstufen und –formationen von Yünnan und
Südwest Setschuan. Botanische Jahrbücher
54: 578-597. Morell
V. 2002. China hotspot. National Geographic
201: 98-113. National
Environment Protection Agency of China. 1998. China’s
biodiversity: a country study. China Environmental
Science Press, Beijing. Olson
D.M. and Dinerstein E. 2002. The global 200: Priority
ecoregions for global conservation. Ann. Missouri
Bot. Gard. 89: 199-224. Pei
S.J. 2001. Ethnobotanical approches of traditional
medicine studies: Some experiences from Asia. Pharmaceutical
Biology 39: 74-79. Wang
C. 1961. The forests of China with a survey of grasslands
and desert vegetation. Maria Moors Cabot Foundation
Publication 5. Harvard University Press, Cambridge, Massachusetts. Wang
W.T., Wu S.G., Lang K.Y., Li P.Q., Pu F.T., and Chen S.K.
(eds) 1994. Vascular plants of the Hengduan Mountains.
Vol 1-2. Science Press, Beijing. Wang
X.P., Yang Z.H., Horng J.S., Iwatsuki K., Yong S.K., Hamilton
A.C, and Davis S.D. 1995. Regional overview: China
and East Asia. In Davis S.D., Heywood V.H., and Hamilton
A.C. (eds), Centers of plant diversity. Information
Press, Oxford. Xiao
P.G. 1991. The Chinese approach to medicinal plants
– their utilization and conservation. In Akerele
O., Heywood V.H. and Synge H. (eds), The conservation
of medicinal plants. Cambridge University Press,
Cambridge, U.K.: 305-313. back
to top of this page |
