modelwasoptimizedbyatwo-stepgridsearchmethod.Twohyperparametersγandσ2.Theresultsshowthat:(1)Thespectralreflectanceofsoilincreaseswiththeincreaseofwavelength,andthereflectancecurvehasobviousabsorptioncharacteristicsat460,550,580,740and900nm.(2)FromtheanalysisoftheresultsofthePLSRmodelandtheLS-SVMmodel,itcanbeseenthatthenonlinearmodelLS-SVMhasbetterpredictionaccuracy,whichmaybeduetothenonlinearrelationshipbetweensoilspectralinformationandsoilphysicalandchemicalproperties.(3)Thecharacteristicwavelengthscreenedbythecontinuousprojectionalgorithmimprovesthemodelaccuracyandoptimizesthemodeloperationefficiency.TheSPA-LS-SVMmodelwasthebestpredictivemodelamongallthemodels,amongwhichtheR2preoftheorganicmattermodelwas0.8847,theRMSEpwas0.1048,andtheRPDwas2.9450.TheR2preofthetotalnitrogenmodelwas0.9018,theRMSEpwas0.0104,andtheRPDwas3.1911.(4)Thisstudyshowsthatvisible/near-infraredspectroscopycanmeasuredifferenttypesofsoilorganicmatterandtotalnitrogencontent,achievingbetterpredictionresults.Visible...