Investigation of heavy metalloid pollutants in the south of Tehran using kriging method and HYDRUS model

Geoscience Letters

Official Journal of the Asia Oceania Geosciences Society (AOGS)

Table 5 Comparing circular, spherical, Gaussian model in different variograms

Element	The variogram model	RMSE	MAE	MBE	R	Nugget	Partial sill	Range
Copper	Circular	23.733	22.522	−22.523	0.727	0.062	0.015	553.603
	Exponential^*	5.714	3.486	−0.002	0.704	0.072	0.005	553.603
	Gaussian	6.649	4.131	−0.042	0.507	0.027	0.038	527.84
	Spherical	6.418	3.971	−0.031	0.561	0.075	0	553.621
Nickel	Circular	1.364	1.018	0.091	0.98	0.008	0.018	524.552
	Exponential	2.35	1.253	0.025	0.912	0.003	0.025	551.284
	Gaussian	1.83	1.361	−0.202	0.961	0	0.026	552.36
	Spherical^*	0.565	0.424	−0.105	0.997	0.01	0.016	551.213
Lead	Circular	25.649	16.131	−0.442	0.565	0.044	0.052	533.84
	Exponential	31.536	29.239	2.314	0.598	0.011	0.056	527.84
	Gaussian	28.649	12.131	−0.142	0.523	0.017	0.033	529.84
	Spherical^*	10.692	7.502	−0.358	0.85	0.091	0.011	385.49

The models were selected with regard to minimum RMSE, MAE, MBE, and maximum R from Table 5.