MRI: Development of a Dual-Wavelength, Ground-Based, Echidna® Lidar (DWEL) for Structural Characterization and Virtual Reconstruction of Forest Canopies

这一重大研究仪器(MRI)奖资助开发一种新的地面扫描激光雷达野外仪器--双波长针织激光雷达(DWEL)，该仪器将测量森林树冠结构参数，并为各种生态和生态系统应用提供森林的三维重建。DWEL将同时从下方用两个波长扫描森林树冠：1064纳米和近1540纳米。在1064 nm处，森林中的大多数目标(树叶、树枝、树干、落叶、土壤)在0.4-0.6的范围内具有类似的反射率。然而，在1540 nm处，树叶和光合作用物质明显比木材和树枝暗。因此，DWEL将更容易地将叶与茎和枝分开，从而提高叶面积指数和叶轮廓提取的准确性。三维重建，再加上双波长能力，也为直接测量树干、树枝和树叶的体积打开了大门，从而无需异速生长方程就可以估计绿色和木质生物量。DWEL的开发将探索3D可视化在大学环境生物学教学中的应用，培训本科生和研究生仪器开发，并探索在中学生的环境教育中进行独特可视化的机会。这项研究的结果将由学生和教职员工在区域和国家会议上传播，并通过出版同行评议的期刊出版物来传播。

This Major Research Instrumentation (MRI) award funds the development of a new, ground-based, scanning lidar field instrument, the Dual-Wavelength Echidna Lidar (DWEL), that will measure forest canopy structural parameters and provide 3-D reconstructions of forests for a variety of ecological and ecosystem applications. DWEL will simultaneously scan the forest canopy from below in two wavelengths: 1064 nm and near 1540 nm. At 1064 nm, most targets in forests (leaves, branches, trunks, leaf litter, soil) have similar reflectances in the range 0.4-0.6. At 1540 nm, however, leaves and photosynthetic materials are significantly darker than wood and branches. Accordingly, DWEL will more easily separate leaves from stems and branches, enhancing the accuracy of leaf area index and foliage profile retrievals. 3-D reconstructions, coupled with the dual wavelength capability, also open the door to direct measurements of volumes of trunks, branches, and leaves to estimate both green and woody biomass without allometric equations. The development of the DWEL will explore the use of 3-D visualization in college teaching in environmental biology, train undergraduates and graduates in instrumentation development, and explore opportunities for unique visualization in environmental education of secondary school students. Results from this study will be disseminated by students and faculty at regional and national meetings, and through the publication of peer-reviewed journal publications.