云南不同生态区云南松林地上生物量光学遥感饱和特征研究

Optical Remote Sensing Saturation Characteristics of Biomass of Pinus yunnanensis Forests in Different Ecological Regions of Yunnan Province

基于Landsat 8 OLI遥感影像,利用森林资源二类调查数据计算云南松林地上生物量密度,借助地统计学中的半变异函数,对生物量原始波段光谱饱和特征进行分析。结果表明:除CY生态区外,各生态区云南松林生物量均与OLI的b6原始波段均有最强的负相关性。各生态区的b6波段反射率均随着生物量的增大而减小,最终趋于饱和,呈现出一定的规律性。各生态区的生物量饱和值分别为NW的205.863 t/hm^(2)、NE的118.675 t/hm^(2)、CY的223.375 t/hm^(2)、SC的190.385 t/hm^(2)、SW的210.750 t/hm^(2)、SY的167.354 t/hm^(2),较高的饱和值出现在滇中、滇西地区,而较低的饱和点分布于滇东北和滇南地区,这与云南松林的适生区有较强的相关性。本研究可为采用光学遥感数据估测生物量的饱和现象研究提供参考,为生物量的精准反演提供技术支撑。

The study calculated the aboveground biomass density of Pinus yunnanensis forests using forest resource secondary survey data based on Landsat 8 OLI remote sensing images.Using the semi variogram in geostatistics,the spectral saturation characteristics of the original band of biomass were analyzed.The results showed that except for the CY ecological regions,the biomass of P.yunnanensis forests in all ecological regions had the strongest negative correlation with the original band of b6 of OLI.The reflectance of the b6 band in each ecological regions decreases with the increase of biomass and eventually tends to saturation,showing a certain regularity.The biomass saturation values of each ecological regions are 205.863 t/hm^(2) for NW,118.675 t/hm^(2) for NE,223.375 t/hm^(2) for CY,190.385 t/hm^(2) for SC,210.750 t/hm^(2) for SW,and 167.354 t/hm^(2) for SY.The higher saturation values occur in the central and western regions of Yunnan,while the lower saturation points are distributed in the northeast and southern regions of Yunnan,which is strongly correlated with the suitable growth areas of P.yunnanensis forests.This provides a reference for the saturation phenomenon in estimating biomass using optical remote sensing data sources and technical support for precise inversion of biomass.