|
Ratings of Soil Health Parameters |
|
Sr.no. |
Parameter |
Unit |
Low |
Medium |
High |
|
Chemical indicator |
|
1 |
pH (1:2::soil:water::w:v) |
unit less |
<6.5 |
6.5-8.5 |
>8.5 |
|
2 |
Electrical conductivity
(1:2::soil:water::w:v) |
dS m-1 |
<0.2 |
0.2-1.6 |
>1.6 |
|
3 |
Soil organic carbon |
(g kg-1) |
<4.5 |
4.5-7.5 |
>7.5 |
|
4 |
KMnO4 oxidisable
carbon |
(mg kg-1) |
<150 |
150-300 |
>300 |
|
5 |
Available phosphorus
(Bray-P1) |
(mg kg-1) |
<13 |
13-20 |
>20.0 |
|
6 |
Available potassium (NH4OAC,
pH 7.0) |
(mg kg-1) |
<55 |
55-125 |
>125 |
|
7 |
Available iron (DTPA, pH 7.3) |
(mg kg-1) |
<4.8 |
4.8-8.0 |
>8.0 |
|
8 |
Available manganese (DTPA, pH
7.3) |
(mg kg-1) |
<2.0 |
2.0-4.0 |
>4.0 |
|
9 |
Available zinc (DTPA, pH 7.3) |
(mg kg-1) |
<0.6 |
0.6-1.2 |
>1.2 |
|
10 |
Available copper (DTPA, pH
7.3) |
(mg kg-1) |
<0.2 |
0.2-0.4 |
>0.4 |
|
Physical indicator |
|
11 |
Bulk density (Core method) |
(Mg m-3) |
<1.0 |
1.0-1.4 |
>1.4 |
|
12 |
Maximum water holding
capacity
(Keen Box method) |
(%) |
<30 |
30-40 |
>40 |
|
Biological indicator |
|
13 |
Microbial biomass carbon
(MBC)
(Substrate induced respiration method) |
(mg kg-1) |
<200 |
200-500 |
>500 |
|
14 |
Dehydrogenase activity
(24 h incubation at 28 oC) |
(µg TPF g-1 24h-1) |
<50 |
50-150 |
>150 |
|
15 |
Potentially
mineralisable nitrogen
(21 day incubation at 28 oC) |
(mg kg-1) |
<20 |
20-60 |
>60 |
|
16 |
Carbon mineralization (Cmin)
(30 day incubation at 37 oC) |
(µg CO2-C g-1
h-1 ) |
<0.5 |
0.5-1.0 |
>1.0 |
|
17 |
Microbial metabolic quotient
(Cmin last week/MBC) |
(µg CO2-C h-1
kg-1 MBC) |
<0.35 |
0.35-0.65 |
>0.65 |
|
Soil Quality Index
(unit less):
> 0.90 (Excellent); 0.75-0.90 (Very good); 0.50-0.75
(Good)
0.25-0.50
(Poor);
<0.25 (Very
poor)
|
