不同草坪草叶片Pb2+含量的高光谱估测OA

[Objective]Real-time assessment of the heavy metal enrichment capacity of turfgrass-an ideal re-mediation material for reducing environmental pollution-is essential for evaluating remediation effectiveness and de-termining the optimal harvest time of turfgrass heavy metals.[Method]Festuca arundinacea Hong Xiang,Lolium pe-renne Balingian,and Poa pratensis Kentucky were used as experiment materials.Plants were treated with Pb2+(C4H6O4Pb·3H20,0,500,1 000,1 500,2 000 mol/L)solutions.The Pb2+content in turfgrass leaves was mea-sured at the later stage of stress.Canopy spectral data were simultaneously collected using an SOC710VP imaging spectrometer.Vegetation indices highly correlated with leaf Pb2+content were screened using Person correlation coef-ficient method.Pb2+content and its reciprocal transformation were used as dependent variables,vegetation indices as the independent variable,and multiple stepwise regression(MSR)and random forest(RF)methods were applied to establish Pb2+content estimation models.Model performance was compared to evaluate predictive accuracy.[Result]1)At 1 000 mol/L Pb2+,Loliumperenne Balingniao exhibited the highest Pb2+accumulation,followed by pratensis Kentucky,while Festuca arundinacea Hongxiang showed the lowest accumulation.At the higher concentration of 2 000 mol/L,Pb2+accumulation was greatest in Festuca arundinacea Hongxiang,followed by Loliumperenne Baling-niao,with Poa pratensis Kentucky showing the lowest accumulation.2)The turfgrass canopy reflectance spectrum ex-hibited a reflectance peak at approximately 580 nm(green peak),a reflectance valley near700 nm(red valley),and a pronounced increase in reflectance between 760～900 nm,forming a"near-infrared reflectance platform".3)The MSRPb model(R2=0.701 6),demonstrated substantially higher accuracy than the RFPb model(R2=0.279 7),in-dicating that the MSR model more effectively captured changes in Pb2+content within the turfgrass canopy.[Conclusion]This study provides a foundation for the rapid nondestructive detection of heavy metal Pb2+enrichment content in turfgrass leaves.