obviously its vegetable production, especially of leaf and
stem vegetables (which are not suitable for long-term storage), although the Kanto region resembles the whole of
Japan in terms of the composition of its agricultural production at the category level.
7.2.2 Anthropogenic Soils in Reclaimed Areas
(1) Increase in anthropized area accompanied by
urbanization
The Kanto region is a large, highly populated area with a
high population density. The region is widely covered with
concrete and asphalt in the form of buildings and road
constructions. These urbanized areas have been extended by
the conversion of agricultural areas that took place during
Japan’s period of high economic growth after World War II.
The rate of urbanization of agricultural areas was highest in
1992 (MLIT 2007). Although the conversion rate has
decreased recently, the decrease in agricultural land continues. The area of agricultural land reduced by 40% between
1965 and 2005, while the area of urbanized land increased
by 50% in the same period (MLIT, 2007). However, since
the beginning of the twenty-first century, the rate of increase
in the area of urbanized land has been reducing due to
decreasing population. The amount of greenery areas is also
increasing along with the increase in the urbanized area in
the Kanto region from 2000 to 18,000 ha in this half century. The vegetation in these greenery areas stands on
human-made soils.
(2) Human-made soils under greenery areas
In the Tokyo metropolitan area, urban green spaces with
large areas have long land-use histories of anthropogenic
management. Shinjuku Gyoen Park, located in central
Tokyo, has been managed since the late sixteenth century,
when it was the private property of the Daimyo (Japanese
feudal lords). The area has been developed by small- to
large-scale civil engineering works for housing and agriculture both before and after WWII. Artificial plantation has also
been established on the land through large-scale civil engineering works. Civil engineering processes can be identified
on soil profiles. A drastic change in soil color, structure, and
texture indicates a process of cut and bank at the ground
surface of the park. Frequent small-scale civil engineering
works can also be recognized by changes in soil softness
(Uoi et al. 2013). Despite the soil disturbance, these soils can
be classified as Haplic or Humic Allophanic Andosols
(Allophanic Andosols Reformed Phase) according to the Soil
Classification System of Japan. Additionally, soils containing
many artifacts in the soil profile are sporadically found in the
park, and are classified as “Mineral Artifactual Soils.”
The Institute for Nature Study, located in the Minato
Ward in Tokyo, has also been the site of civil engineering
Fig. 7.8 Local differences from all Japan data in agricultural product composition during 2011–2015 a composition of agricultural products by
categories in all Japan and the Kanto region b local differences from all Japan data in agricultural product composition. (Figure supplied by Kenji
Kanazawa)
7 Kanto-Koushinetsu Region
255
stem vegetables (which are not suitable for long-term storage), although the Kanto region resembles the whole of
Japan in terms of the composition of its agricultural production at the category level.
7.2.2 Anthropogenic Soils in Reclaimed Areas
(1) Increase in anthropized area accompanied by
urbanization
The Kanto region is a large, highly populated area with a
high population density. The region is widely covered with
concrete and asphalt in the form of buildings and road
constructions. These urbanized areas have been extended by
the conversion of agricultural areas that took place during
Japan’s period of high economic growth after World War II.
The rate of urbanization of agricultural areas was highest in
1992 (MLIT 2007). Although the conversion rate has
decreased recently, the decrease in agricultural land continues. The area of agricultural land reduced by 40% between
1965 and 2005, while the area of urbanized land increased
by 50% in the same period (MLIT, 2007). However, since
the beginning of the twenty-first century, the rate of increase
in the area of urbanized land has been reducing due to
decreasing population. The amount of greenery areas is also
increasing along with the increase in the urbanized area in
the Kanto region from 2000 to 18,000 ha in this half century. The vegetation in these greenery areas stands on
human-made soils.
(2) Human-made soils under greenery areas
In the Tokyo metropolitan area, urban green spaces with
large areas have long land-use histories of anthropogenic
management. Shinjuku Gyoen Park, located in central
Tokyo, has been managed since the late sixteenth century,
when it was the private property of the Daimyo (Japanese
feudal lords). The area has been developed by small- to
large-scale civil engineering works for housing and agriculture both before and after WWII. Artificial plantation has also
been established on the land through large-scale civil engineering works. Civil engineering processes can be identified
on soil profiles. A drastic change in soil color, structure, and
texture indicates a process of cut and bank at the ground
surface of the park. Frequent small-scale civil engineering
works can also be recognized by changes in soil softness
(Uoi et al. 2013). Despite the soil disturbance, these soils can
be classified as Haplic or Humic Allophanic Andosols
(Allophanic Andosols Reformed Phase) according to the Soil
Classification System of Japan. Additionally, soils containing
many artifacts in the soil profile are sporadically found in the
park, and are classified as “Mineral Artifactual Soils.”
The Institute for Nature Study, located in the Minato
Ward in Tokyo, has also been the site of civil engineering
Fig. 7.8 Local differences from all Japan data in agricultural product composition during 2011–2015 a composition of agricultural products by
categories in all Japan and the Kanto region b local differences from all Japan data in agricultural product composition. (Figure supplied by Kenji
Kanazawa)
7 Kanto-Koushinetsu Region
255