Oh, Jeong Soo, Joon
Hwan Shin, and Jong Hwan Lim
Department
of Forest Ecology, Forestry Research Institute, Korea
Forest vegetation in Korea can be
largely divided into warm temperate, cool temperate and frigid forest zone. The
cool temperate forest zone of them occupies the largest part of the Korean
peninsula and it is generally divided into three subdivisions such as northern,
central and southern subzone. The Forestry Research Institute established three
long-term ecological research sites at Kwangnung Experiment Forest in the
central subzone of the cool temperate forest zone, at the Mt. Kyebangsan Forest
in the northern subzone of the cool temperate forest zone, and at the Mt.
Keumsan Forest in the warm temperate forest zone. The objectives of long-term
ecological research in the Forestry Research Institute, Korea are to study
long-term changes of the forest ecosystems in energy fluxes, water and nutrient
cycling, forest stand structure, biological diversity, to quantify nutrient
budgets and fluxes among forest ecosystem compartments and to integrate
ecological data with a GIS - assisted model. To achieve the objectives, forest
stand dynamics, environmental changes in soil properties, stream water quality,
nutrient cycling and air pollution, biological diversity have been investigated
and plant phenology as an indicator of climate change has been monitored in the
LTER sites.
INTRODUCTION
Korea is located from 33°06′
to 43°01′of
north latitude and from 124°11′
to 131°53′of
east longitude, which is a peninsula country in the East Asia, bounded on most
of its northern border by China and partly by Russia. On the southern part of
Korea, the Korean Strait separates the peninsula from Japan.
The Korean peninsula has a temperate
climate characterized by wet monsoon in summer season and by continental
climate in winter season with freezing weather. During the summer time it is
hot and humid with frequent rain showers, while it is cold and dry in winter.
Seasonal changes are gradual but distinctive; spring and autumn are relatively
short while summer and winter are rather long. The annual mean temperature extends from 3℃
to 16℃ and the annual precipitation ranges from
600 to 1,600 millimeters (Figure 1). Due to its diverse distribution of climate
conditions and its topographic complexity, Korea exhibits various types of
forests.
Forest vegetation in Korea can be
largely divided into warm temperate, cool temperate and frigid forest zones
(Figure 2). The warm temperate
forest zone covers the area south of the 35th parallel of latitude, a part of
the southern coastal region, Cheju island and a large number of southern islands
where the annual mean temperature is higher than 14℃.
Evergreen broad-leaved forests are typical in this zone, but the majority of
natural forests were destroyed by over-exploitation and forest fires and
subsequently has changed to deciduous broad-leaved forests, mixed forests or
pine forests. Dominate species are Quercus
acuta, Castanopsis cuspidata and Camellia
japonica.
Fig.1 Annual precipitation
and temperature
The cool temperate forest zone is
located between 35° and
43°
of north latitude except for mountainous highlands. The annual mean temperature
ranges from 6℃
to 13℃. This zone is generally divided into
three subdivisions such as northern, central and southern temperate forest
subzone. Deciduous broad-leaved forests are representative in this zone, but
quite large forests were destroyed and were altered into pine forests. The
resultant pine forest has usually developed into a sub-climax stage. Further
destruction of some forests has provoked problems of soil erosion. The dominent
tree species of this zone are Quercus,
Acer, Carpinus, Betula and Pinus.
The frigid forest zone, called
the coniferous forest zone, covers the northern part of the Korean peninsula
and the mountainous highlands where the annual mean temperture is below 5℃.
The coniferous forests are representative in this zone. When the forests are
disturbed by over-exploitation or forest fire, they usually change to deciduous
broadleaved forests which are composed of Betula,
Populus, Larix and so on. The dominent species are Abies nephrolepis, Picea jezoensis, Larix gmelini var.
principis-ruprechtii and Betula
platyphylla.
Figure
2. Forest vegetation zone of Korean peninsula
LTER SITES
The Forestry Research Institute
established long-term ecological research sites in three forest zone, namely,
the Kwangneung Experiment Forest (KEF) in the central temperate forest subzone
of the cool temperate forest zone, the Mt. Kyebangsan Forest in the northern
temperate forest subzone of the cool temperate forest zone, and Mt. Keumsan
Forest in the warm temperate forest zone
Figure
3. Long-term ecological research sites
1. Kwangneung Experiment Forest (KEF)
The Kwangnung area had been
protected as a royal tomb forest for the 7th King Sejo of Chosun Dynasty since
1468. Most of the originally protected area was designated as KEF in 1913 whose
area is 2,240 ha. The area of Kwangneung Natural Reserve Forest is about
1,200ha, which is located at the Soribong peak and has been protected from
human activities. Elevation of Kwangneung range from 90m to 600m. The highest peak is Mt. Chugyopsan
(600.6m). There are Mt. Soribong
(536.8m), Mt. Yongamsan (476.9m), and Mt. Cheonkyunsan (393.1m) that make this
area topographically rugged. Annual mean air temperature is 11.3℃,
and precipitation is 1,365mm.
The forest mainly consists of
unique old-growth forests composed of broad-leaved trees in the middle zone of
temperate forest in Korea. It is
found that about 796 native plant species have grown in this area (FRI Korea,
1994), which is dominated by typical tree species of middle temperate zone in
Korea such as Quercus spp., Carpinus spp., Cornus spp. Acer spp. and
Pinus densiflora (Lee et al., 1990; Oh et al., 1991).
The vegetation of Soribong area
was identified as Carpinus laxiflora
community group and the group was classified into typical Carpinus laxiflora community, Acer
mono-Staphylea bumalda community
and Pinus densiflora community by
Braun-Branquet table method of Z-M school (Oh et al., 1991). The vegetation of Mt. Chugyop area was also Carpinus laxiflora community group and
the group was classified into Cornus
controversa-Alangium platanifolium var. macrophyllum community and Rhus trichocarpa-Atractylodes japonica community.
To investigate the changes
in forest stand structure in time, 1 ha permanent plot was established at the KEF
reserve forest area from 1998 to 1999. At the plot, all of the trees larger
than 2cm in DBH were labeled, and location, DBH, height, crown width were
measured. Standing dead trees larger than 5cm in DBH were also labeled and the
location and DBH were measured, and wood debris on the floor larger than 5cm in
diameter were drawn (Figure 4).
The density of the trees was 1,473 per ha, total biomass 261 tons/ha,
and basal area 28㎡/ha.
Dominate tree species is Quercus serrata which
occupies 51% in basal area, and followed by 23% of Carpinus laxiflora, 7.8% of C.
cordata, and 3.9% of Acer mono. Q. serrata is dominant at the
canopy layer, but at the sub-canopy and suppressed tree layers are dominated by
the two Carpinus species.
Fig.4. Stemmap of KEF LTER
site (100m´100m)
2. Mt. Kyebangsan Forest
The Mt. Kyebangsan Forest is
located in a mountainous highland from 900m to 1577m above sea level. The dominate species of the forest
are Quercus mongolica, Betula schumidtii,
Kalopanax pictus, Tilia amurensis, Pinus densiflora and Abies holophylla.
The site was designated as Reserve Forest for research in 1991. Ground-survey
on biological diversity was conducted from 1995 to 1997. The research site is
located at the ecotone between the northern cool temperate forest and
sub-alpine forest.
Figure
5.
A diameter growth measuring band on a Pinus
densiflora tree
3. Mt. Keumsan Forest
The Mt. Keumsan Forest is located
in a land-tied island with bridge to the south coast of the Korean peninsula.
The dominant species of the forest are Quercus,
Carpinus, Acer and Pinus. The
site was designated as Experiment Forest of the Forestry Research Institute in
1983. Ground-survey on biological diversity was conducted in 1994.
DESCRIPTION of THE
RESEARCH PROGRAMME
The objectives of long-term
ecological research in the Forestry Research Institute are to study long-term
changes of the forest ecosystem in energy fluxes, water and nutrient cycling,
forest stand structure, biological diversity, to quantify nutrient budgets and
fluxes among forest ecosystem compartments, and to integrate ecological data
with a GIS-assisted model. To achieve the objectives, we have investigated the
following items
①
Forest Stand Dynamics : measure every 5 years for 1 ha permanent quadrat
- Trees larger
than or equal to 5cm in DBH : labelling, identifying species and measuring DBH,
height, crown widths, and location.
- Trees smaller
than 5cm in DBH : identifying species and measuring height
- Diameter
Growth : monthly measuring diameter growth for sample trees
·Sub-alpine
Forest (Mt. Kyebangsan from 1996 : Quercus
mongolica, Pinus densiflora, Kalopanax pictus, Betula schmidtii)
·Cool
Temperate Forest (KEF from 1998 : Quercus
serrata, Carpinus laxiflora, Carpinus cordata)
·Warm
Temperate Forests (Mt. Turyunsan from 1998 : Camellia japonica, Quercus acuta, Dendropanax morbifera)
②
Environmental Changes
- Forest
Micro-Meteorology : air/soil temperature, relative air/soil humidity, wind
direction and speed, (KEF from 1999, Mt. Kyebangsan from 1999)
- Fluxes of
Energy and Water (Figure 6, KEF from 1999, and CO2 from 2001) : eddy covariance
system, soil heat flux.
- Soil and Site
Survey
- Stream Water
Quality
- Carbon and
Nutrients Cycles : above ground and processes in soil
- Air Pollution
: pH of rain and SO2 concentration in air by month
③
Changes of Biological Diversity
- Plant
Population Dynamics
- Vertebrate
(fishes, amphibian, reptiles, birds, mammals)
- Invertebrate
(in soil, on forest floor, on air, in canopy, in water)
- Microbes
(mushrooms, mycorrhizae, lichens)
④
Monitoring as an Indicator of Climate Change
- Measuring
bursting of buds and expansion rate of leaves for the sample trees at the designated dates on the
spring
Literature Cited
Forestry
Reserch Institute. 1994. Kwangneung Experiment Forest. 910pp. Utkomunhwasa,
Seoul. (in Korean)
Figure 6. A tower for canopy access and
measuring fluxes of energy and water vapor by eddy covariance method in KEF
LTER site.
Lee,
K.J., J.C. Jo, B.C. Lee and D.S. Lee. 1990. The structure of plant community in
Kwangneung forest (Ⅰ):
Analysis on the forest community of Soribong area by the classification and
ordination techniques. J. Kor. For. Res. Sco. 79(2):173-186 (in Korean)
Oh,
J.S., B.C. Lee, J.H. Shin, S.W. Oh and S.I. Kim. 1991. Community classification and stand structure of
Kwangneung Natural Reserve Forest. Res. Rep. For. Res. Inst. 42:36-56 (in
Korean)