Soil Quality Assessment Strategies for Evaluating Soil Degradation in Northern Ethiopia

Table 7

Dataset selection, scoring function, and indexing method comparisons for eight LUSMS in the Mai-Negus catchment of northern Ethiopia.

SQ indexing method	Linear scoring function						Nonlinear scoring function
	I^L		II^L		III^L		I^N		II^N
	Range	𝑆	Range	𝑆	Range	𝑆	Range	𝑆	Range	𝑆
Unscreened-SQI^a	0.410–0.913	2.227	0.475–0.941	1.981	0.405–0.899	2.220	0.562–0.956	1.701	0.559–0.953	1.705
PCA-SQI^a	0.347–0.913	2.631	0.418–0.923	2.208	0.341–0.881	2.584	0.513–0.973	1.898	0.546–0.964	1.766
Unscreened-SQI^b	0.397–0.937	2.360	0.434–0.943	2.173	0.361–0.925	2.562	0.511–0.966	1.890	0.508–0.964	1.897
PCA-SQI^b	0.335–0.796	2.376	0.369–0.799	2.165	0.307–0.779	2.537	0.420–0.818	1.952	0.418–0.816	1.948
Mean	—	2.399	—	2.132	—	2.476	—	1.859	—	1.830

adenotes minimum dataset chosen using principal component analyses (PCA).
bdenotes minimum dataset chosen by expert opinion (EO).
I^L: Liebig method LSF; II^L: Homothetic transformation method of LSF; III^L: Glover method LSF; I^N: CurveExpert method NLSF; II^N: Glover method NLSF; S: Sensitivity analysis; LSF: linear scoring function; NLSF: nonlinear scoring function.