Table 3.

Results of principal component analysis (PCA) of soil quality indicators.

Principal components (PC)	PC1	PC2	PC3	PC4
Eigen value	9.185	1.660	1.451	1.124
% of total variance	0.540	0.098	0.085	0.066
Cumulative %	0.540	0.638	0.723	0.789
Factor loadings/Eigen vectors
Physical indicator
Bulk density (Mgm−3)	−0.853	0.084	0.307	0.087
Physico-chemical indicator
pH	0.938	0.006	−0.019	−0.030
Electrical conductivity (dSm−1)	0.891	−0.008	−0.155	0.148
Chemical indicator
Total organic carbon (g kg−1)	0.918	0.067	−0.278	−0.051
Particulate organic carbon (g kg−1)	0.965	−0.041	0.015	−0.007
Permanganate Oxidizable Carbon (g kg−1)	0.739	0.254	−0.288	−0.197
Available nitrogen (kg ha−1)	0.893	−0.097	0.176	0.158
Bray's phosphorus (kg ha−1)	0.854	−0.165	0.337	0.023
Available potassium (kg ha−1)	0.845	−0.152	0.271	−0.053
DTPA Zinc (mg kg−1)	−0.047	0.660	−0.099	−0.517
DTPA Copper (mg kg−1)	0.031	0.756	−0.060	0.207
DTPA Iron (mg kg−1)	0.747	−0.159	−0.223	−0.206
DTPA Manganese (mg kg−1)	0.073	0.178	−0.678	0.401
Biological indicator
Fluorescein di acetate (μg fluroscein g−1 h−1)	0.557	−0.071	0.272	0.242
Dehydrogenase (μg TPF g−1 h−1)	0.447	0.561	0.425	−0.106
β-glucosidase (μg p-nitrophenol g−1 soil h−1)	0.908	−0.094	−0.165	−0.222
Microbial biomass carbon (mg kg−1)	0.569	0.365	0.387	0.436

*Factor loadings in bold are considered highly weighted.