| |
| Soil |
| In Korea, the soil is mainly
composed of residual soil from weathered rocks and sandy soil from
widely spread granite. Due to the use of chemical fertilizers,
much of the soil has become acid. Influenced by weather
conditions, in cold areas the soil is mainly white gray. The
warmer the area the redder the soil gets. Therefore in most parts
of Korea, the soil is brown. In some areas, the soil is black due
to weathered soil from carbonate rocks and past volcanic activity.
In addition, around rivers and in some low lying areas, alluvial
soil is found; this soil it settled after being carried by winds
or streams. These areas are very fertile, making optimal fields
for rice farming. |
| Mountains |
| Nearly 70 percent of the Korean Peninsula is
covered by mountains and hills that have not gone through any
dramatic changes; the result is low and gentle slopes being
produced after long periods of erosion. The mean height above sea
level of the mountains is 482 m, this is far lower than the Asian
average of 960m and mountains that are higher than 1000m are
mostly located in eastern areas, thus rivers run toward the West
Sea and South Sea. The southwest area is composed of low
mountains. The long stretching high mountains have had great
influence on the lives of the Korean people, resulting in
remarkable differences in cultures and climates between the
eastern and western parts. Major roads including highways are laid
in the south-north direction rather than east-west. |
 |
| About two-thirds of the Korean
Peninsula is composed of pre-Cambrian metamorphic and granite
rocks. Although the distribution of sedimentary rock is very
limited, limestone is abundant in some regions and several
limestone caves have developed, some of them are very large and
attract tourists. Among the most famous caves are Gossigul,
Gosugul and Seongnyugul, all of which are liberally decorated with
stalagmites and stalactites. |
| Ribers |
| Due to an upheaval of the Mesozoic age and
the upheaval in the east side during the Cenozoic Period, most of
the rivers flow into the Yellow Sea and the South Sea. The streams
running to the Yellow Sea are generally short in length and slow
and have high levels of discharge; while those running to the East
Sea are short, fast and have low level of discharge. The discharge
of rivers fluctuates very much due to the heavy rainfall in summer
and narrow streams. The fluctuation of river discharges causes
difficulties with floods, water supply, hydropower generation and
water transportation. Most streams run in meandering patterns
resulting in frequent floods. In order to avoid the damage from
floods, various efforts have been made to straighten rivers and
build dikes. |
 |
| Due to the differences in tide
levels between high and ebb tides, most of streams are tidal
rivers. Tidal rivers are mainly located in eastern and southern
coastal areas with gentle slopes; where tides show marked
differences. In summer, rivers in these area tend to inundate the
surrounding land when the flood waters meet the high tide. In the
western plains area, many dikes have been built in order to ward
off damage from such inundation. |
| Plains |
| Most of the plains are floodplains developed
along rivers running into the Yellow Sea and South Sea, especially
in the lower reaches. Plains are found on a small scale in the
eastern area. In inland areas, plains have been developed between
valleys due to erosions caused by streams between mountains.
Erosion basins have been created along rivers in areas of granite
rocks. Surrounded by mountains, these areas with abundant water
were used for protection from external intrusion and growing rice.
In the past people gathered in these areas and developed
settlements; while today, cities have been developed around these
areas. The natural dikes created along both sides of rivers are
well drained, providing fields for habitation and vegetation
growing. The plots behind the dykes are used for rice growing
after installing proper drainage systems. |
 |
| Coastal Areas |
| The coastal areas were shaped into the
current form 4000 years ago when the sea reached the current level
after the last glacial age. The mountain ranges in the east
coastal area, composed of high mountains, run closely along the
East Sea, resulting in smooth shorelines. The shorelines of the
south and west coasts are very irregular with innumerable small
peninsulas and bays as well as a large number of islands. The east
coast has small tidal ranges, and wave activity shaped coastal
features in the area. The west coast has a large tidal range that
created the current coastline. The shorelines of the south and
west coasts are very irregular and tidal flats are common coastal
features especially in bays into which rivers discharge sediment
during floods. Tidal flats have been long used to cultivate
shellfishes and have been recently reclaimed to provide rice
fields, residential areas or industrial sites. |
 |
| Sandy beaches have developed in
areas that protrude toward the sea and are used as resorts. Due to
the high northwesterly winds in winter, sand hills have developed
and people established forests to protect farming areas from
strong winds and sand. The east coast has steep slopes and fast
streams that carry sediment that to create sandy beaches and
lagoons by blocking small streams in the lower reaches. With
mountains and hills facing the sea, sea cliffs have been created
along the coast. In addition, the ground upheaval and changed sea
level developed coastal terraces where roads run and settlements
formed. These geographical features are found in areas, south of
Samcheock or Pohang. |
| Ocean |
| In Korea, surrounded by the sea
on three sides, people have been heavily dependent on the sea for
natural resources and transportation. The East Sea is 1700m deep
on average and has great differences between low and high tide
levels. The East Sea, where the warm and cold currents meet, has
abundant fishery resources. The West Sea is only 44m deep and the
continental shelves developed in this area are expected to be
further utilized for natural resources including fisheries.
Efforts have been made to avoid the damage caused by the big
differences between low and high tides. With low salt levels,
northwesterly winds and shallow water, the West Sea is not
abundant with fish. The South Sea is 101m deep and has
well-developed continental shelves. Due to year-round warm
currents, the water temperature stays at a constant level in the
South Sea and it is the best fishing grounds of all the seas
surrounding the Korean Peninsula. |
|
|
