Impact of Forage Fertilization with Urea and Composted Cattle Manure on Soil Fertility in Sandy Soils of South-Central Vietnam

Table 2

Means and standard deviations for composition of composted cattle manure from the supplying farm in Cát Trinh Commune on a dry matter basis.

Parameter	Mean	SD
Dry matter (%)	50	8.4
Organic matter (g/kg)	261	99
Mineral matter (g/kg)	739	99
C : N	12.8	2.3
Total N (g/kg)	12	3
Organic N (g/kg)	11	3
P (mg/kg)	2733	1302
K (mg/kg)	6750	4105
Ca (mg/kg)	9988	3581
Mg (mg/kg)	3088	1094
Na (mg/kg)	955	661
S (mg/kg)	2090	516
B (mg/kg)	14	4
Fe (mg/kg)	4266	2196
Mn (mg/kg)	791	129
Cu (mg/kg)	27	25
Zn (mg/kg)	110	25

Organic matter was estimated by loss-on-ignition at 550°C for 2 h [18] and mineral matter was calculated as 100 − %OM.
1.724 factor was applied to convert organic matter (OM) to C, based on the assumption that loss-by-ignition = OM and OM contains 58% organic carbon (Factor of Wolff, as cited in Pribyl [19]).
Means and standard deviations (SD) were calculated from 14 treatment applications, and each treatment application was an average of 3 subsamples.