Table 2.7 Selected local soil types with farmers’ soil quality assessments in six villages of Yen
Chau district, north-west Vietnam, with corresponding total Nitrogen (Nt) stocks and available
bases (S-value), plus land suitability classes considering and not considering slopes
Village/
site
Local soil knowledge Scientific soil knowledge
Sustainability
class
a
Local soil
type
Quality
evalu.
b
WRB
soil
type
Stocks
Nt
kg m
À2 Evalu.
b
S-Value
mol c m
À2 Evalu.
c
+
slope
À
slope
Khau Khoang
T3
Yellow soil l
Alisol 1.1
h
73
mh
N
S2
Ban Dan
M1
Light red
soil
l
Luvisol 1.1
h
264
vh
N
S2
P2
Red yellow
soil
m
Alisol 1.5
h
284
vh
S3
S1
Keo Bo C
A4
Stony
yellowblack
l
Luvisol 1.2
h
213
vh
N
S2
S1
Stony
yellow
black
l
Luvisol 0.5
mh
202
vh
N
S3
Cho Long
B86
Yellow soil l
Alisol 1.7
h
94
mh
S3
S2
B79
Yellow soil l
Luvisol 1.0
mh
108
h
S3
S2
Kho Vang
H3
Red soil
l
Alisol 0.24
l
296
vh
N
S3
Y3
Red soil
l
Luvisol 0.26
m
215
vh
N
S3
Chieng Khoi
Site 4
d
Good black
soil 1
h
Luvisol 0.87
mh
193
h
N
S2
Site 4
d
Good black
soil 2
h
Luvisol 0.61
mh
138
h
N
S2
Yellow
soil 1
m
Alisol 0.51
mh
18
m
N
N
Yellow
soil 2
m
Alisol 0.81
mh
60
mh
S2
S2
Catena 2
d Poor red
sandy
soil 1
l
Alisol 0.21
l
9
l
N
N
Catena 2
d Poor red
sandy
soil 2
l
Alisol 0.38
m
16
m
N
N
a
According to FAO/ITC-Gent (Sys et al. 1993): S1 very suitable, S2 moderate suitable,
S3 marginal suitable, N unsuitable
b
Nt (kg m
À2
): 0.1–0.25 ¼ low, 0.25–0.5 ¼ moderate, 0.5–1 ¼ moderate high, 1–2 ¼ high,
c
S-value (mol c kg m
À2
): 1–10 ¼ low, 10–50 ¼ moderate, 50–100 ¼ moderate high, 100–200 ¼
high, >200 very high
d
s. Fig. 2.19
72
K. Stahr et al.