western part. Although no significant change in Mg and K
contents has been observed, the proportion of soils with
deficiencies in both elements is relatively high.
(4) Saitama Prefecture
The total area of agricultural land in Saitama Prefecture is
75,000 ha. This mainly consists of paddy (42,000 ha),
upland (30,000 ha), and orchard (3000 ha) soils. The most
dominant types of paddy soil are Gray Fluvic soils and Gley
Fluvic soils, which occupy almost the same area. Peat soils
are distributed in the southeastern region. Allophanic
Andosols are the dominant soil (34%), followed by Gray
Fluvic soils (17%). In orchard fields, Allophanic Andosols
are the most dominant soil group in the eastern plateau area,
and Brown Forest soils are the most dominant soil group in
the Chichibu area.
The results of the “Soil-Environment Monitoring Project”
are described below. The average values in the plow layer at
monitoring sites (65 paddy soils, 26 upland soils, and 16
grove soils) from the fifth (1999–2003), sixth (2004–2008),
and seventh (2009–2013) surveys are presented in Fig. 7.12.
(a) Paddy soil
The concentrations of available phosphate and exchangeable
potassium meet a prefectural soil diagnostic criteria, as
shown in Fig. 7.12. In recent years, the application of
slow-release fertilizer based on prefectural cultivation standards and varietal characteristics of rice has been spreading.
(b) Upland and orchard soil
Generally, fertilizer components tend to accumulate in the
upland soil. In particular, exchangeable Ca accumulated in
the plow layer of upland fields due to liming and the
exchangeable Ca/Mg ratio tends to be higher there. However, the ratio of exchangeable Mg to exchangeable K tends
Fig. 7.11 Current status and changes of the cultivated soil properties. The side bar graph is the relative frequency (1994*97). A bar graph is an
annual change (1:1979*82,2:84*87,3:89*92,4:94*97). (Adapted from National Farmland Soil Guidebook 2012)
7 Kanto-Koushinetsu Region
259
contents has been observed, the proportion of soils with
deficiencies in both elements is relatively high.
(4) Saitama Prefecture
The total area of agricultural land in Saitama Prefecture is
75,000 ha. This mainly consists of paddy (42,000 ha),
upland (30,000 ha), and orchard (3000 ha) soils. The most
dominant types of paddy soil are Gray Fluvic soils and Gley
Fluvic soils, which occupy almost the same area. Peat soils
are distributed in the southeastern region. Allophanic
Andosols are the dominant soil (34%), followed by Gray
Fluvic soils (17%). In orchard fields, Allophanic Andosols
are the most dominant soil group in the eastern plateau area,
and Brown Forest soils are the most dominant soil group in
the Chichibu area.
The results of the “Soil-Environment Monitoring Project”
are described below. The average values in the plow layer at
monitoring sites (65 paddy soils, 26 upland soils, and 16
grove soils) from the fifth (1999–2003), sixth (2004–2008),
and seventh (2009–2013) surveys are presented in Fig. 7.12.
(a) Paddy soil
The concentrations of available phosphate and exchangeable
potassium meet a prefectural soil diagnostic criteria, as
shown in Fig. 7.12. In recent years, the application of
slow-release fertilizer based on prefectural cultivation standards and varietal characteristics of rice has been spreading.
(b) Upland and orchard soil
Generally, fertilizer components tend to accumulate in the
upland soil. In particular, exchangeable Ca accumulated in
the plow layer of upland fields due to liming and the
exchangeable Ca/Mg ratio tends to be higher there. However, the ratio of exchangeable Mg to exchangeable K tends
Fig. 7.11 Current status and changes of the cultivated soil properties. The side bar graph is the relative frequency (1994*97). A bar graph is an
annual change (1:1979*82,2:84*87,3:89*92,4:94*97). (Adapted from National Farmland Soil Guidebook 2012)
7 Kanto-Koushinetsu Region
259