Study On Remote Sensing Monitoring Mechanism Of Peat Bog

Peatland has a strong carbon sequestration capacity and natural geological record characteristics,and peat occupies a very important position in the global carbon cycle and climate change research.Sphagnum is the key source of the peat accumulation,and it is also the indication plant of peat bog ecological environment.Therefore,Sphagnum monitoring is very necessary to the study of carbon cycle and ecological environment change in peat area.The distribution of peat bog is mainly concentrated in the northern high latitudes,and the Sphagnum is more fragile and susceptible to temperature,rainfall and evaporation changes.The traditional method of sampling by the ground has not been able to meet the needs of monitoring.In order to improve the timeliness and accuracy,remote sensing technology of vegetation monitoring methods have been large-scale research and application.Considering the physiological and structural characteristics of Sphagnum,the existing remote sensing inversion method for vascular plants can not realize the exact inversion of Sphagnum.This study explores the spectral mechanism of peat moss by studying the spectral difference between sphagnum and vascular plants,and finds out the spectral specificity of sphagnum.According to the specific characteristics of sphagnum spectrum,the inversion model of sphagnum is established,and the accuracy of the model is verified.The aim of the experiment is to improve the accuracy of peat bog and provide scientific basis for the monitoring of sphagnum ecological environment.The main conclusions of this study are as follows:(1)Sphagnum and vascular plants in the spectrum are significantly different.In the cell structure band,peat moss at 1000 nm by the cell structure and water content under the common effect,is significantly different from the specificity of vascular plants,and the characteristics are more stable,so you can use the cell structure band to distinguish between sphagnum and vascular plants by remote sensing.(2)Pigmentation is the main factor affecting the spectral characteristics of sphagnum and vascular plants.The chlorophyll and carotenoid content of sphagnum is less than that of vascular plants,which makes the reflectance of the two in the visible light band.The moss is in different growth stages and different varieties,and the content of anthocyanins is different.And the red Sphagnum spectrum characteristics in the pigment part is also significantly different,with the increase in anthocyanin content,the spectrum appears "Red-Shift" phenomenon.(3)Based on the reflectance of 1006 nm band,the sphagnum water content inversion model can accurately invert the water content of sphagnum.Based on the correlation analysis of single-band and vegetation index of sphagnum,the reflectivity of sphagnum in 1006 nm band was significantly correlated with its water content.The best model was the univariate nonlinear quadratic polynomial model with the average error of 6.379 %.