Using geospatial data to understand the relationship between tropical forest phenology and productivity

这个项目将调查在对比潮湿和干燥的热带森林生境中，叶物候-叶生产的时间和数量-和初级生产力之间的关系。热带森林是地球上最大和最多样化的生物群落之一。 然而，这些地区对总初级生产力（GPP）-碳循环的最大通量-的估计并不十分了解。由于气候的季节性和物种的多样性，热带森林的叶物候变化很大。此外，还不清楚这些动态如何影响森林生产力。利用卫星进行的地理空间监测提供了前所未有的能力，可以跟踪不同地点和不同季节的森林动态。将这些尖端技术与地面测量相结合，将有助于确定大规模地理空间模式所依据的特定地点的过程，从而更准确地解释卫星观测结果。该项目将通过与现有的外展计划合作，将研究与教育和公民科学相结合，该计划为初中和高中学生提供户外，基于场所的体验式环境教育。博士后研究人员将与初中和高中教师合作，教育和培训未来的空间科学家，为拟议的研究提供地理空间数据，同时满足下一代科学标准，以帮助培养更有数据能力的劳动力。叶片物候和生长季节长度被认为是控制陆地碳循环的主要因素，通过设定光合作用和植物生长的时间长度。然而，在热带地区，一年四季都是生长季节。此外，目前还不清楚GPP的变化如何与叶物候的变化联系在一起。新的卫星测量太阳能诱导荧光（SIF）将提供一个代理全球PP在大范围内重复的时间间隔。虽然SIF相关的研究正在积累，全球和大陆规模的模式还没有联系到发生在地块规模的过程。本计画将利用无人机及卫星观测资料，结合地面物候资料，探讨叶片物候、气候季节性与生产力之关系。这项工作的结果将有助于解开生产力和物候在不同的热带森林之间的关系，并推进我们的理解机制和特定地点的差异，卫星SIF的大尺度变化。在这项研究中开发的方法将有广泛的适用性，以广泛的环境变化和保护application.This奖项反映了NSF的法定使命，并已被认为是值得通过使用基金会的智力价值和更广泛的影响审查标准进行评估的支持。

This project will investigate the relationship between leaf phenology – the timing and amount of leaf production – and primary productivity in contrasting wet and dry tropical forest habitats. Tropical forests are one of the largest and most diverse biomes on Earth. Yet, estimates of gross primary productivity (GPP) – the largest flux of the carbon cycle – are not well understood from these regions. Leaf phenology in tropical forests can be highly variable because of climatic seasonality and a diversity of species. Further, it is unclear how these dynamics affect forest productivity. Geospatial monitoring from satellites provides an unprecedented ability to track forest dynamics across sites and seasons. Merging these cutting-edge technologies with ground-based measurements will help identify site-specific processes that underlie broad-scale geospatial patterns leading to more accurate interpretation of satellite observations. This project will integrate research with education and citizen science by working with an existing outreach program, which provides outdoor, place-based, experiential environmental education to middle and high school students. A postdoctoral researcher will collaborate with middle and high school teachers to educate and train future spatial scientists, providing geospatial data for the proposed research while also meeting Next Generation Science Standards to help grow a more data-capable workforce.Leaf phenology and growing season length are thought to be primary factors controlling the terrestrial carbon cycle by setting the length of time available for photosynthesis and plant growth. Yet in the tropics there is a year-round growing season. Further, it is unclear how variation in GPP is tied to changes in leaf phenology. New satellite measurements of solar-induced fluorescence (SIF) will provide a proxy for GPP across large extents at repeated intervals. While SIF-related studies are accumulating, global and continental scale patterns have not been linked to processes occurring at the plot-scale. This project will synthesize ground-based phenology data with unmanned aerial vehicle and satellite measures of SIF to investigate the relationship between leaf phenology, climatic seasonality, and productivity. Results from this work will help disentangle the relationship between productivity and phenology in diverse tropical forests, and advance our understanding of mechanisms and site-specific differences underlying broad scale variation in satellite SIF. The methods developed in this study will have broad applicability to a wide range of environmental change and conservation applications.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.