1. © The Author(s) 2015. Published by Science and Education Publishing.
Table 5A. Critical limits for interpreting levels of soil chemical properties from literatures
Soil properties
Very low
Low
Moderate
High pH
<3.0
>7.5
Organic carbon (gkg-1)
<2.0
5.5-10
>10
Total nitrogen (gkg-1)
<1.5
>5.0
Available phosphorus (gkg-1)
8.0-20
>20
Potassium (Cmolkg)
<2.2
>1.10
Calcium (Cmolkg)
2.0
5.0-10
>10.0
Magnesium (Cmolkg)
<0.5
Iron (mgkg-1)
<50
55-75
75-105
>105
Zinc (mgkg-1)
Manganese (mgkg-1)
<10
20-40
40-100
>100
Copper (mgkg-1)
10-20
25-40
>40
ECEC (Cmolkg-1)
10-15
15-2x0
Source: Hazelton & Murphy, (2007); Kparmwang & Malgwi, (1979); Isirima et al., (2003); Abe et al., (2010); FAO (1996); Holland et al., (1989); Uquetan, (2013).
Uquetan U. I. et al. Evaluation of Soil Quality in Relation to Landuse Effect in Akamkpa, Cross River State – Nigeria.
Applied Ecology and Environmental Sciences, 2017, Vol. 5, No. 2, doi: /aees-5-2-2
© The Author(s) Published by Science and Education Publishing.