Assessmentofsoilqualityisimportantforoptimumproductionandnaturalresourcesconservation.AgriculturalandpasturesoilqualitiesofDeh-SorkhregionlocatedatsouthofMashhad,northeasternIranwereassessedusingtheintegratedqualityindex(IQI)andNemeroqualityindex(NQI)modelsincombinationwithtwodatasets,i.e.,totaldataset(TDS)andminimumdataset(MDS).Inthisstudy6soilpropertiesconsideredasMDSwereselectedoutof18propertiesasTDSusingprinciplecomponentanalysis.Soilsampleswerepidedinto3groupsbasedonoptimumrangesof8soilphysicalqualityindicators.Soilsampleswiththemostindicatorsatoptimumrangewereselectedasgroup1andthesampleshavingfewerindicatorsatoptimumrangewerelocatedingroups2and3.Optimumrangesofsoilporesizedistributionfunctionswerealsodeterminedassoilphysicalqualityindicesbasedon8soilphysicalqualityindicators.Poresizedistributioncurvesofgroup1wereconsideredastheoptimumporesizefunctions.Theresultsshowedthatrelativelyhighorganiccarboncontentscouldimproveporesizedistribution.Meancomparisonsofsoilphysicalqualityindicatorsdemonstratedthatmeanweightdiameterofwetaggregates,structuralstabilityindex,theslopeofmoistureretentioncurveatinflectionpoint,andplantavailablewatercontentinagriculturallandusedecreasedsignificantlyinrelationtopasturelanduse.Inaddition,theresultsdemonstratedthatthestudiedMDScouldbeasuitablerepresentativeofTDS.78%ofpasturesoilshadtheoptimumporesizedistributionfunctions,whilethisparameterforagriculturalsoilswasonly13%.Ingeneral,thesoilsofthestudiedregionshowedhighlimitationsforplantgrowthaccordingtothestudiedindicators.
