Accurate estimation of forest carbon stocks by 3-D remote sensing of individual trees
Accurate estimation of forest carbon stocks by 3-D remote sensing of individual trees
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DOI：
10.1021/es0259887
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发表时间：
2003-03-15
影响因子：
11.4
通讯作者：
Akiyama, Y
中科院分区：
文献类型：
--
作者：
Omasa, K;Qiu, GY;Akiyama, Y
森林是地球上最重要的碳汇之一。然而，由于森林结构复杂、地理变化多端、面积大，森林碳储量的准确估算对现场调查和遥感都是一个挑战。基于这些原因，《京都议定书》要求建立估算森林碳储量的方法（《京都议定书》第5条）。应对这一挑战的一个可能的解决方案是远程测量整个森林中每一棵树的碳储量。在这里，我们提出了一种估算日本雪松林碳储量的方法，该方法使用一种高分辨率、直升机载的三维扫描激光雷达系统，测量森林中每棵树的三维树冠结构。结果表明，该方法可获得木质冠层的数字图像（10cm网格）。可以以合理的精度自动检测树顶。树高测量的绝对误差范围在42厘米以内。高度与碳储量的异速生长关系允许通过测量每棵树的碳储量来估计总碳储量。因此，我们建议我们的方法可以在林分尺度上准确地估算日本雪松林的碳储量。定期测量将揭示森林碳储量的变化。
Forests are one of the most important carbon sinks on Earth. However, owing to the complex structure, variable geography, and large area of forests, accurate estimation of forest carbon stocks is still a challenge for both site surveying and remote sensing. For these reasons, the Kyoto Protocol requires the establishment of methodologies for estimating the carbon stocks of forests (Kyoto Protocol, Article 5). A possible solution to this challenge is to remotely measure the carbon stocks of every tree in an entire forest. Here, we present a methodology for estimating carbon stocks of a Japanese cedar forest by using a high-resolution, helicopter-borne 3-dimensional (3-D) scanning lidar system that measures the 3-D canopy structure of every tree in a forest. Results show that a digital image (10-cm mesh) of woody canopy can be acquired. The treetop can be detected automatically with a reasonable accuracy. The absolute error ranges for tree height measurements are within 42 cm. Allometric relationships of height to carbon stocks then permit estimation of total carbon storage by measurement of carbon stocks of every tree. Thus,we suggest that our methodology can be used to accurately estimate the carbon stocks of Japanese cedar forests at a stand scale. Periodic measurements will reveal changes in forest carbon stocks.