广域空间尺度上植被净初级生产力的精确推算

作者介绍了使用遥感、GIS数据和BEPS生态过程模型推算植被净初级生产力(NPP)的方法。为了准确推算北海道地区NPP,我们改进了BEPS模型,而且使用了高质量GIS数据作为模型的输入数据。通过计算得出1998年北海道NPP的平均值为644 g C/m2,总量为0.078 Gt C。我们还进行了模型输入数据质量对应用生态过程模型推算NPP的精度影响测试。结果表明,高质量的GIS输入数据可以提高NPP推算精度16.6%~39.7%。

Accurate Estimation of Net Primary Productivity of Terrestrial Ecosystem at a Regional Scale

This paper describes a method for the estimation of the net primary productivity (NPP) by integrating remotely sensed and GIS data with a process-based ecosystem model. Hokkaido Island of Japan was selected as a case to validate our method. In order to improve the estimation accuracy, we improved the BEPS model (Boreal Ecosystem Productivity Simulator) for NPP estimation by incorporating new land cover classification logic, a robust Normalized Difference Vegetation Index-Leaf Area Index (NDVI-LAI) algorithm and employing GIS data with high quality as the input of the model. As the results of the model calculation, the mean and total NPP for the study area in 1998 was 644 g C/m 2 /yr and 0.078 Gt C/yr, respectively. In addition, the effect of the quality of the model input requirements on accurate NPP estimation using a process-based model was also assessed. The results show that the higher quality input data obtained from GIS datasets for a process-based model improved the NPP estimation accuracy for Hokkaido Island by about 16.6%-39.7%.