Rapid Determination Of Chemical Properties In Paddy Soil By Near Infrared Diffuse Reflection Spectroscopy

A very large number of industries have paid attention to and being apply to the near infrared spectroscopy(NIR)analysis,which has become a research hotspot because of its convenience,efficiency,and wide application.Moreover,the near infrared spectroscopy analysis is called Green analytics technology,Analysis giant and Instantaneous analysis technique.Therefore,it has important theoretical and practical significance to explore the possibilities of predicting chemical properties rapidly in paddy soil from near infrared spectral.In this experiment,paddy soil sample collected from the six provinces in china(Sichuan,Guizhou,Hunan,Jiangxi,Jilin,Liaoning).This article established and improved the near infrared spectral rapid determination method of the main chemical properties of paddy soil by determine the total nitrogen,organic carbon,alkaline nitrogen,available phosphorus,available potassium,and soil pH,and gather the near-infrared spectra in paddy soil samples.This experiment collected the near-infrared spectrum by diffuse reflection.This article construct the near-infrared spectrum models of total nitrogen,organic carbon,alkaline nitrogen,available phosphorus,available potassium,and soil pH for paddy soil by PLS,MLR and PCR.The results show that:In the model of chemical properties of paddy soil established by near infrared spectroscopy analysis,the PLS model is better than MLR and PCR.The near infrared spectroscopy is a feasible method to predict total nitrogen,organic carbon,alkaline nitrogen and pH of paddy soil.Of which,the optimal model result for total nitrogen is Factors=10,Rc~2=0.913,Rv~2=0.8830,RMSECV=0.022g/kg,RPD=3.094.The optimal model result for organic carbon is Factors=10,Rc~2=0.852,Rv2=0.815,RMSECV=0.339g/kg,RPD=2.319.The optimal model result for alkaline nitrogen is Factors=8,Rc~2=0.790,Rv~2=0.752,RMSECV=21.100mg/kg,RPD=1.750.The optimal model result for soil pH is Factors=10,Rc~2=0.837,Rv~2=0.804,RMSECV=0.615mg/kg,RPD=1.903.Under the experiment conditions,the calibration model for predicting available potassium and available phosphorus in paddy soil by near infrared spectroscopy analysis is not reliable.In short,soil properties can be quickly determine by near infrared spectroscopy.Although its precision still need further study and improvement,its application prospect is very broad.