主被动遥感数据协同估算干旱区草原植被生物量

结合主动微波遥感和被动光学遥感反映地表植被的各自优势,发展了一种主被动遥感协同估算干旱区草原植被生物量的模型。该模型将植被覆盖度作为水云模型的附加参数,将总体散射分为植被覆盖区散射和裸土区散射两部分,将水云模型应用到了植被覆盖稀疏区域。利用改进的水云模型和双极化ASAR数据,通过建立方程组估算植被生物量。将该方法用于乌图美仁草原植被生物量的估算,验证了该方法的有效性。结果表明:该主被动遥感协同估算模型能够成功地估算干旱区草原植被生物量,并且取得了较好的估算精度(R2=0.8562,RMSE=0.1813kg/m2)。最后,分析了该方法估算植被生物量的误差来源。

Estimation of Vegetation Biomass in Arid Region with Active and Passive Remote Sensing Data

Integrating the respective advantages of optical and microwave data for the vegetation,an optical and microwave synergistic method for the Above Ground Biomass (AGB) in the prairie of arid regions was developed in this paper.Vegetation coverage was combined in water cloud model as additional information.The total backscattering was divided into the amount attributed to areas covered with vegetation and attributed to areas of bare soil.Thus,the water cloud model can be applied in the sparse vegetation cover area.Using the modified water cloud model and dual-polarization ASAR data,the vegetation biomass was estimated by the established equations.The method was applied to estimate the AGB of Wutumeiren prairie.The results indicated that the method of active and passive remote sensing synergy was of the operational potential in AGB.And the better accuracy of the biomass retrieval was achieved(R²=0.8562,RMSE=0.1813 kg/m²).Finally,the error of biomass estimation using this method was analyzed.