by
Seok-Woo LEE42
Forest trees are essential for human society. They provide fuel, fiber, building materials, food and medicines among other things. Forests stabilize environments and trees are cornerstones of ecosystems. While trees are the dominant components of the ecosystem, forests are also rich reservoirs of other biological diversity, and home to many animal and plant species. To maintain and improve our forests, the genetic resources of forest trees must be conserved. Management of forest genetic resources involves developing overall strategies, applying specific methodologies, implementing new techniques, and coordinating local, national, regional, and global efforts.
Forests are a dominant feature of Korea's landscape. They cover 6.42 million ha or 65 percent of the country. However, over the past four decades human population pressures, industrialization and land use changes have gradually reduced Korea's forests.
At the beginning of the 20th century, modern silvicultural practices and regulated forest management practices were introduced in Korea. Silvicultural activities such as clear-cutting and the establishment of plantation monocultures, together with overexploitation during the Japanese occupation and severe devastation during the Korean war, had a negative effect on Korean forests, by simplifying forest ecosystems, reducing biodiversity, and diminishing ecosystem resilience.
When the Institute of Forest Genetics (IFG) was established in 195643, the Korean government initiated a conservation program of forest genetic resources. At that time, the conservation program focused on ex situ conservation, such as the establishment of clone banks of selected superior trees showing good stem form and/or outstanding growth. In 1972, the IFG began exploring, evaluating, and conserving natural stands of some economically important tree species. However, these efforts were not systematic and emphasis was placed on securing breeding materials rather than on conserving genetic diversity.
In 1994-1995, the IFG developed a new strategy for the systematic conservation of forest tree genetic resources. The new strategy combines in situ and ex situ conservation approaches. The choice of strategy will depend on various factors, for instance, the size of the population considered, its genetic characteristics, isolation of the population, capacity for regeneration, and possibility to ensure its long-term survival.
The implementation of the new strategy includes, (1) collection of existing information, mapping of distribution range and genetic variation of target species covered by the strategy; (2) exploration and evaluation of target tree species, including determination of their ecological traits and genetic diversity; (3) field inspection, selection, and demarcation of in situ conservation stands; and (4) field inspection, selection, and collection of reproductive material for the establishment of ex situ conservation stands and conservation in a seed bank.
Forest classification in Korea is based primarily on vegetation and climate. Due to the topographical complexity and a range of climatic conditions, the forest types of Korea are highly diverse and the number of indigenous tree species is very high in spite of the small land area of the country. To date, over 1 000 tree species have been described in Korea.
The evergreen deciduous forests are found south of 34°N, especially along the coastlines, and contain species of the genera, Camellia, Daphniphyllum, Ilex, Pittosporum, evergreen Quercus and others. Annual average temperature of this zone is over 14°C.
The broad-leaf deciduous tree zone (temperate forests), is located between 35°N and 43°20´N, excluding high mountainous regions and plateaus. The annual average temperature of this zone ranges from 5 to 14°C. Dominant tree species are of the genera, Quercus, Betula, Zelkova, and Fraxinus . In addition, Pinus densiflora and P. thunbergii are widely distributed in this zone.
The coniferous forest zone covers the extreme north of Korea and high altitude mountainous regions; the annual average temperature does not exceed 5°C. This zone is characterized mainly by the species of the genera, Picea, Abies, Pinus, Larix, Taxus and others.
In the past, in situ conservation initiatives in Korea were largely driven by heritage value and aesthetic concerns. More recently, the issues of habitat protection for rare and endangered species and protection of genetic resources have increasingly influenced in situ conservation efforts.
To date, the KFRI has set aside 33 natural forest stands of approximately 2 674 ha for in situ conservation of forest genetic resources of 13 tree species (nine coniferous and four broad-leaved tree species) see table 1.
Table 1. In situ conservation of forest genetic resources in Korea
Species |
No. of populations |
Area (ha) |
Pinus densiflora |
4 |
2 015 |
Pinus thunbergii |
1 |
14 |
Pinus koraiensis |
2 |
33 |
Pinus pumila |
1 |
2 |
Abies nephrolepis |
2 |
28 |
Abies koreana |
2 |
32 |
Abies holophylla |
1 |
30 |
Picea abies |
1 |
9 |
Taxus cuspidate |
4 |
110 |
Populus maximowiczii |
1 |
5 |
Quercus mongolica |
9 |
354 |
Quercus variabilis |
4 |
31 |
Cornus controversa |
1 |
11 |
Total |
33 |
2 674 |
Only limited silvicultural interventions, such as thinning and salvage cutting, are permitted in the in situ conservation stands. Seeds and other propagules have been collected for ex situ conservation, including gene conservation stands composed of identical progenies and seed storage. The gene conservation stands, include genetic materials found in the in situ conservation stands as a safeguard against unintended losses caused by natural and/or man-made causes and they thus complement these.
In addition to the in situ conservation stands for forest genetic resources, various kinds of protected areas, such as "natural environment conservation area", "natural ecosystem conservation area", "biosphere reserve", "virgin forest protection area", and "reserved forest", make a contribution to the conservation of forest genetic resources. The total area of these protected areas is 206 947 ha. Protection in such areas includes all associated plants, animals, fish, and other biological resources. A large number of national and provincial parks also contribute to the in situ conservation of forest genetic resources. Since the early 1980s, 20 national parks (383 357 ha) and 20 provincial parks (73 248 ha) have been designated.
Tree breeding in Korea to date has been mainly focused on commercially important conifers. Pinus koraiensis and P. densiflora are by far the most important tree species in tree breeding programmes. P. thunbergii and Abies holophylla are also of interest.
Among the deciduous tree species, tree improvement efforts have been made mainly in Populus spp. Several fast growing hybrids such as Populus alba × P. gladulosa, P. nigra × P. maximowiczii and P. koreana × P. nigra var. italica have been developed and released for large-scale planting.
Ex situ conservation includes seed banks, clonal archives, arboreta, and breeding populations etc.
The first seed orchard in Korea was established in 1968. To date, a total of 726 ha of seed orchards for 20 tree species (9 conifers and 11 broad-leaved tree species) have been established. The seed orchards began to produce seeds in 1976. During the past 20 years, these seed orchards have produced about 75 tons of seeds.
So far, a total of 2 724 plus trees of 29 tree species (1 582 trees of 11 conifers and 1 142 trees of 18 deciduous species) have been selected. Since 1962, clonal genebanks have been established for 11 conifers (1 568 clones covering 45.3 ha) and nine deciduous tree species (510 clones covering 23 ha).
Provenance tests for 14 native and 99 exotic tree species and progeny tests (14 species), are managed to also yield information on genetic variation, useful in developing gene conservation strategies for the species concerned.
The cultivar collections, especially for fruits (and nuts) and ornamental tree species, amount to 21.3 ha, including 1 536 cultivars of 53 species, such as Castanea crenata, Hibiscus syriacus, Juglans sinensis, Corylus heterophylla, and Rubus coreanus. The KFRI has also established a botanical garden which has value also for gene conservation, and includes a total of 103 rare and endangered tree species and varieties such as Abeliophyllum distichum and Berchemia berchemiaefolia.
In 1998, the KFRI constructed modern facilities for short- and long-term storage of tree seeds. Since that time, around 2 200 seeds from 220 tree species have been collected and are being stored at low temperatures (4, -4, and -18°C)
Knowledge of the diversity and distribution of genetic variation is crucial to managing genetic resources, because such information makes it possible to predict the likelihood of gene loss in a population. It also makes it possible to develop strategies to prevent such loss and to conserve genetic diversity in a more efficient way.
While our factual knowledge of genetic variation for most tree species is still very sparse, a considerable amount of knowledge of genetic variation has been gained by isozyme analysis in some economically important tree species such as pines, oaks, and yew (Kim et al., 1993; Kim et al., 1997; Lee and Lee, 1997; Lee et al., 2000); and in rare and endangered tree species such as Koelreuteria paniculata, and Abeliophyllum distichum (Lee et al.. 1997a and c; Lee et al.. 1998). Additionally, other molecular techniques are being developed to clarify the genetic variation of a number of tree species. The molecular markers being developed and applied in Korea are: Random Amplified Polymorphic DNAs (RAPDs), Amplified Fragment Length Polymorphisms (AFLPs), Inter Simple Sequence Repeats (ISSRs), and microsatellites (Lee et al.. 1997b; Hong et al.. 2000).
Extensive ecological studies on forest tree stands which will be conserved in situ are underway. Species composition, the number of trees by species, and the soil's physical and chemical properties are being investigated, such information is vital to successful management of the natural stands intended for in situ conservation.
Temporal and spatial genetic variation of a number of tree species are also under study, including species studies of Pinus densiflora, P. koraiensis and Abies holophylla. The results of these studies can be used to support in situ conservation, in the development of sampling strategy for ex situ conservation, and in the determination of effective population size. For these purposes, various kinds of advanced geostatistical analyses are used, such as spatial autocorrelation and variography (Hong et al. 2001a and b).
Silvicultural practices could have differing genetic effects in forest stands. Thus, there is a need to establish how different management activities may influence the genetic structure of naturally and/or artificially regenerated forests. The KFRI is trying to assess the impacts of the various silvicultural treatments on the genetic structure of tree species, especially conifers. Such studies may provide valuable information for the successful management of in situ and ex situ conservation stands.
In 2001, the KFRI developed a user-friendly database for forest genetic resources, for the following purposes: (1) to provide an up-to-date national overview of in situ and ex situ conservation activities; (2) to promote collaboration among Korean forestry institutes involved in conservation activities; (3) to serve as a centralized, national archive of Korean forest genetic resources and (4) to provide easy access to information on the distribution and the availability of genetic resources in Korea with a view of supporting research activities and preventing duplication of scientific efforts.
There will be increasing emphasis on the conservation of forest resources in the near future of Korea. By ensuring the conservation of genetic resources, the country will be better able to utilize them using new biotechnologies as well as conventional tree breeding. The inventory of forest resources will also enable the country to be well-prepared in international negotiations with regard to forest gene conservation. Finally, the approach used in Korea can provide valuable information to other countries intending to establish a conservation strategy for forest tree genetic resources.
Hong, Y.P., Cho, K.J., Kim, Y.Y., Shin, E.M., and Pyo, S.K. 2000. Diversity of I-SSR variants in the population of Torreya nucifera. Jour. Korean For. Soc. 89: 167-172.
Hong, K.N., Kwon, Y.J., Chung, J.M., Shin, C.H., Hong, Y.P. and Kang, B.Y. 2001a. Spatial genetic structure at a Korean pine (Pinus koraiensis) stand on Mt. Jumbong in Korea based on isozyme studies. Jour. Korean For. Soc. 90: 43-54 (in Korean).
Hong, K.N., Choi, Y.C., Kang, B.Y. and Hong, Y.P. 2001b. Spatial genetic structure of needle fir (Abies holophylla) seedlings on the forest gap within a needle fir forest at Mt. Odae in Korea. Jour. Korean For. Soc. 90: 565-572 (in Korean).
Kim, Z.S., Lee, S.W. and Hyun, J.O. 1993. Allozyme variation in six native oak species in Korea. Ann. Sci. For. 50(suppl. 1): 253s-260s.
Kim, Z.S., Lee, S.W. and Hwang, J.W. 1997. Genetic diversity and structure of natural populations of Pinus thunbergii in Korea. Silvae Genetica 46: 120-124.
Lee, S.W., Kim, S.C., Kim, W.W., Han, S.D. and Yim, K.B. 1997a. Characteristics of leaf morphology, vegetation and genetic variation in the endemic populations of a rare tree species, Koelreuteria paniculata Laxm. Jour. Korean For. Soc. 86: 167-176 (in Korean).
Lee, S.W., Kim, Y.Y., Hyun, J.O. and Kim, Z.S. 1997b. Comparison of genetic variation in Pinus densiflora natural populations by allozyme and RAPD analysis. Korean J. Breed. 29: 72-83 (in Korean).
Lee, S.W., Kim, C.S., Cho, K.J. and Choi, W.Y. 1997c. Genetic variation in the endemic rare tree species, Empetrum nigrum var. japonicum K. Koch. Korean J. Breed. 29: 376-381 (in Korean).
Lee, S.W. and Lee, M.H. 1997. Genetic variation of Juglans sinensis in Korea. Silvae Genetica 46: 102-107.
Lee, S.W., Kim, S.C., and Lee, H.S. 1998. Allozyme variation in Abeliophyllum distichum Nakai, an endemic tree species of Korea. Silvae Genetica 47: 294-298.
Lee, S.W., Choi, W.Y., Kim, W.W. and Kim, Z.S. 2000. Genetic variation of Taxus cuspidata Sieb. et Zucc. in Korea. Silvae Genetica 49: 124-130.
40 Received June 2002. Original language:
English
41 This is a revised version of a paper, "Republic of Korea responds to UNCED treaty obligations with new conservation strategies for forest tree resources" published in Diversity 13: 11-13.
42 Dept of
Tree Breeding, Korea Forest Research Institute, 44-3 Omokchun-dong, Kwonsun-ku,
Suwon 441-350, Rep. of Korea, Email: [email protected]
43 In 1998 the
Institute of Forest Genetics was combined with the Korea Forest Research
Institute (KFRI) to become the Dept of Tree Breeding and in 2002, Dept of Tree
Breeding were renamed to Dept of Forest Genetic Resources.
