论文部分内容阅读
植物吸收性光合有效辐射分量(FPAR)是描述植被结构以及与之相关的物质与能量交换过程的基本生理变量。选取内蒙古呼伦贝尔谢尔塔拉镇针茅和羊草草甸草原为研究对象,利用2013年5次地面实测实验,通过HJ-I CCD高分辨率卫星影像建立统计模型,从而实现对该研究区MODIS/FPAR产品的验证与分析。1km HJ/FPAR“真值”与MODIS/FPAR产品值的变化趋势基本一致,并且二者具有较好的一致性,R2达到了0.6762。MODIS/FPAR产品能够很好地反映呼伦贝尔草甸草原在整个生长季的长势及物候变化,这是因为研究区样地尺度上HJ/FPAR和MODIS/FPAR产品值不但变化趋势相一致,而且相关系数R2高达0.9148。无论在同尺度(1km)还是整个研究区尺度,MODIS/FPAR均有一定的高估现象。研究结果对了解和进一步使用该地区的MODIS/FPAR产品具有重要的指导意义。
Plant Absorption Photosynthetic Active Radiation (FPAR) is a fundamental physiological variable that describes the vegetation structure and its associated material and energy exchange processes. In this paper, we selected the grassland of Stipa grandis and Leymus chinensis in Hulunbeier Shertha town of Inner Mongolia as the research object. By using 5 field experiments in 2013 and using HJ-I CCD high resolution satellite imagery to establish the statistical model, / FPAR product verification and analysis. The trend of 1km HJ / FPAR “true value ” and MODIS / FPAR product values are basically the same, and the two have a good consistency, R2 reached 0.6762. MODIS / FPAR products can well reflect the growth and phenology of Hulun Buir meadow steppe throughout the growing season, because the sample values of HJ / FPAR and MODIS / FPAR on the plot scale of the study area are not only consistent with the change trend, but also the correlation coefficient R2 is up to 0.9148. MODIS / FPAR has certain overestimation whether it is on the same scale (1km) or the entire study area scale. The findings are important for understanding and further using MODIS / FPAR products in the region.