Important Plants of East Asia II : Endemic Plant Stories
East Asia Biodiversity Conservation Network (EABCN) is monitoring biodiversity
affected by global climate change, including combined flora list covering
East Asia and distribution maps especially for endangered plants. We have published
the first EABCN book ‘Important Plants of East Asia: Plants tell stories’.
We planned a second publishing through collaboration of EABCN members
to understand East Asian plants more deeply. Therefore we mainly selected
plants that have distribution in more than one country. East Asia covers Russia (far
east to east Siberia), Japan, Korea, Mongolia, Continental China, and Taiwan,
with latitude roughly ranging from N20˚ to N80˚ and longitude ranging from
E75˚ to E170˚. Although East Asia is not a homogeneous unit from the natural
point of view, they share geographical closeness and natural historical events.
According to Köppen-Geiger climate classification depending on temperature
and precipitation, East Asia has five major climate zones: polar and alpine, continental,
temperate, dry, and tropical. Such wide variation in climate has contributed
Good (1953) has classified the world flora into 37 provinces. East Asia has
five of them: Arctic and sub-arctic, Euro-Siberian, Sino-Japanese, West and
Central Asiatic, and Continental Southeast Asiatic provinces. This classification
corresponds well to the upper climate one. Euro-siberian province located
northernmost in East Asia is characterized by large scale coniferous forest and
birches. Sino-japanese province is situated in the middle belt of East Asia. It
covers Japan, Korea, middle part of continental China, and Himalaya. Cercidiphyllum
and Eupetalea are endemic there. The distribution of Tiarella polyphylla
includes Japan, Korea, China, and Nepal. West and Central province has little
precipitation. It covers Mongolia and west part of China. Dry-tolerant plants are
observed in steppe. The southern coastal region of continental China, Taiwan,
and the southwestern islands in Japan belong to Southeast Asiatic province.
Barringtonia or mangroves can be observed there.
Another cause of biodiversity is natural historical events. As Pavel Krestov (2014)
showed in the former EABCN book, repeating glacial events can lead to extinction,
movement, isolation, or stay in refugia. Compared to Europe and North
America, the coldness during the glacial period and the warmness during inter
glacial period have affected the flora less because the mountains elongating north
to south can give plants chance to escape southward or northward. The sea has
eased climate change and supplied land bridges during the glacial period. It
promoted isolation during interglacial period. On the other hand, inside the Eurasian
Continent went on desertification and produced more dry-tolerant plants.
As a result, speciation and endemism can characterize East Asia biodiversity.
Asa Gray, a famous American botanist in the 19th century, pointed out the
similarity of floras between eastern North America and East Asia. They share
genera. The distribution disjunction has been interest of botanists. Stewartia, Liquidamber,
Liliodendron, and Platanus are distributed in both regions. The latter
three plants have fossil records in Japan. However, they are extinct today. We
have been sharing the same types of flora or plant species across countries due
to natural historical events. People have been making use of such plants for a
long time. They have developed unique culture with these plants. On the other
hand, we have been also sharing cultures on ethnic use. For example, Japan has
imported a great amount of knowledge on Chinese medicine. Ginkgo, plums,
and bamboos have been imported from China with Chinese culture. After that,
they have modified the culture and developed their own culture. It has been
reported that the bamboo with the origin from China is introduced by a Japanese
researcher. Name of plants can be affected by the culture of each country.
For example, Rosa rugosa is called Roza in Russian with meaning of rose. It is
called Hamanasu in Japanese with the meaning of coastal pear or Haedanghwa
with meaning of coastal pear flower. It is called Meigui in Chinese with the
meaning of red gem.
East Asian countries are also sharing problems concerning the conservation
of biodiversity. Deforestation, development of agricultural field, desertification,
and artificial constructions for slope, riverside, and seaside have been threats to
biodiversity. Changes in life styles can also decrease biodiversity maintained by
traditional sustainable actions such as wood fuel production, abundance of bamboo
use, change of nutrient for agriculture from natural resources to chemicals.
These are common problems in every country. Another new and more serious
problem is global climate change. It affects biodiversity not only by increasing
temperature directly, but also by increasing or decreasing local precipitations,
decreasing snow fall, increasing herbivory and disease.
We hope that we can share knowledge on plants, cultures, and problems that
threaten biodiversity conservation. We could learn the situation and background
of each county in East Asia by collaborating with each other and publishing
this book. Moreover, we can find solutions for various problems across these
Create date 2020-10-30 13:48:49