DISSERTATION RESEARCH: Remote analysis of canopy gap dynamics and limiting similarity in a lowland Neotropical rain forest

树冠空隙是指与形成树冠的树木的折断或死亡相关的植被高度降低。树冠空隙的分布和动态以及导致其变化的过程一直是森林中长期感兴趣的主题，因为林隙与树木再生和化学物质在森林中的移动有关。该项目使用高光谱分辨率遥感来测量冠层氮的变化，并使用激光雷达遥感来量化林隙动态，以检验关于哥斯达黎加拉塞尔瓦热带雨林树种动态的假说。它还将使用长达九年的LiDAR时间序列来检查大片老树林的树冠空隙动态变化。通过将氮的高光谱分析与激光雷达对冠层高度的估计相结合，可以检验总体假设，即在以古老的热带雨林为主的景观中，关键植物功能性状(氮素状况)的局部差异是树木死亡和林隙动态的驱动因素。

A canopy gap is reduced vegetation height associated with the breakage or death of a canopy-forming tree. The distribution and dynamics of canopy gaps, and the processes responsible for their variation, have been the subject of long-term interest in forests, because gaps are associated with tree regeneration and the movement of chemicals through the forest. This project uses high spectral resolution remote sensing to measure variation in canopy nitrogen, and LiDAR remote sensing to quantify gap dynamics, to test hypotheses about tree species dynamics in the tropical rain forest at La Selva, Costa Rica. It will also examine variation in canopy gap dynamics using a nine-year LiDAR time series for a large tract of old-growth forest. By integrating hyperspectral analyses of nitrogen with LiDAR estimates of canopy height, the overall hypothesis can be tested that local variance in a key plant functional trait (nitrogen status) is a driver of tree mortality and gap dynamics across a landscape dominated by old-growth tropical rain forest.