Table 1: Soil chemical properties before biosolids application and biosolids composition from the North Wastewater Treatment Plant at Chihuahua city, Mexico.

ConstituentaSoilBiosolidsElementSoilBiosolids

pH6.56.7Ca (mg kg−1)8503,412
OM (%)0.5512Mg (mg kg−1)1251,037
TCC (%)FreeFreeNa (mg kg−1)2371,312
EC (dS m−1)1.43Cu (mg kg−1)19
N- (mg kg−1)6066Fe (mg kg−1)430
P (mg kg−1)87Mn (mg kg−1)1415
K (mg kg−1)362962Zn (mg kg−1)3111

OM: organic matter; TCC: total calcium carbonate; EC: electrical conductivity; N-NO3 and the rest of the elements are extractable and expressed on a dry weight basis.