Development of a multi-temporal effective leaf area index model from multi-spectral lidar; Scaling to Sentinel-1 and Sentinel-2 data using machine learning****

激光雷达是一种遥感技术，用于绘制植被三维结构特性的变化，包括植被高度。需要绘制树叶覆盖和叶面积指数（LAI），以模拟生态系统如何利用大气中的二氧化碳进行光合作用。虽然单脉冲，离散返回激光雷达系统显示出估计冠层覆盖的前景，转换为叶面积指数需要物种类型和木本与叶状材料的比例的知识。可以使用多光谱（MS）激光雷达系统来实现这些的识别。MS激光雷达是一种相对较新的技术，它结合了激光脉冲的快速发射和三种不同波长的脉冲接收。这些组合可以用来估计不同的木本和叶状成分和物种的比例。该技术的发展对于验证卫星光学遥感估算的叶面积具有重要的益处，叶面积通常用作广阔和偏远地区LAI的指标。哈特菲尔德公司已经开发了基于光学遥感的方法来推导叶面积指数，他们将根据机载激光雷达数据和实地验证方法进行放大。莱斯布里奇大学将与哈特菲尔德公司合作。开发MS激光雷达方法，使用数字半球摄影（DHP）验证森林和湿地的麦克默里堡和麦凯堡附近的网站。这一应用程序的开发，以绘制叶面积指数将添加到这个创新的加拿大MS激光雷达技术的能力范围，作为一个可扩展的“基于地块”的方法，用于量化的关键参数，以估计加拿大的森林和湿地的碳吸收。

Lidar is a remote sensing technology that is used to map the variations in the three-dimensional structural properties of vegetation, including vegetation height. Mapping of foliage cover and leaf area index (LAI) are required to model how ecosystems use atmospheric carbon dioxide for photosynthesis. While single pulse, discrete return lidar systems show promise for estimating canopy cover, conversion to leaf area index requires knowledge of species type and the proportion of woody vs. leafy material. Identification of these may be achieved using a multi-spectral (MS) lidar system. MS lidar is a relatively new technology that combines rapid emission of laser pulses and reception of these pulses in three different wavelengths. The combination of these may be used to estimate the proportions of different woody and leafy components, and species. The development of this technology has important benefits for validation satellite optical remote sensing estimates of foliage area, which is often used as an indicator for LAI over broad and remote regions. Hatfield Inc. have developed optical remote sensing-based method for deriving LAI, which they will scale up from airborne lidar data and field validation methods. The University of Lethbridge will partner with Hatfield Inc. to develop MS lidar methods validated using digital hemispherical photography (DHP) for forest and wetland sites proximal to Fort McMurray and Fort McKay. The development of this application for mapping of LAI will add to the range of capability of this innovative Canadian MS lidar technology as a scalable 'plot-based' method for quantifying a critical parameter used to estimate carbon uptake by Canada's forests and wetlands.