Doctoral Dissertation Research: Intensive Phenological Monitoring of Wisconsin's Northern Mixed Forest, Integrating In-situ and Remote Sensing Observations

春季植物物候（开始生长）是生物圈对全球气候变化反应的一个重要指标。它还为进一步了解低层大气边界层动力学和生物圈-大气能量/物质交换开辟了可能性。在过去的十年里，随着卫星观测和生物气候建模的数据变得越来越可用，物候学与大规模生态系统监测更加相关。然而，由于缺乏能够在像素一级精确核实卫星数据的密集地面测量，来自遥感器的信息的精确度仍然低于预期。为了充分发挥物候监测的作用，需要有计划地观察和表征整个景观的地表物候。这项研究的特点春季植物物候在景观尺度，并准备一个方法基础，包括空间分布的实地观察，以促进更可靠和综合的物候监测植被动态。将利用统计学、空间分析、地质统计学和数字图像处理技术对这些现场数据以及相应的卫星数据、土壤调查数据、数字高程模型等进行分析。这笔赠款将支持第二年春季实地活动和研究设备的维护/改进。这一项目将是第一个以高时间和空间分辨率纳入大量地面物候学的项目之一，以确定植物物候学和生物圈-大气层在景观一级的相互作用。这些数据的性质将使两种观测尺度具有相同的分辨率，从而能够合理地验证卫星得出的物候指数。因此，这项研究也是一项开创性的工作，旨在探索有效的方法来监测区域到全球尺度的生物圈对全球变化的反应，通过空间尺度的桥梁和协同整合的现场和遥感物候数据。学生调查员将使用这个项目来支持完成他的博士论文。收集的数据和测试的方法将有助于其他研究生和感兴趣的研究人员进行后续和相关研究（物候观测将通过互联网门户共享）。从广义上讲，更好地了解景观物候和生物圈对全球气候变化的反应，对于加强对地球系统的科学认识，支持社会适应和可持续发展努力，是非常重要的。

Springtime plant phenology (onset of growth) is a critical indicator of biospheric response to global climate change. It also opens up possibilities to further understand lower atmospheric boundary layer dynamics and biosphere-atmosphere energy/matter exchange. With data from satellite observations and bioclimatic modeling becoming more available over the past decade, phenology is even more relevant for large scale ecosystem monitoring. However, due to the lack of intensive ground measurements which would allow precise validation of satellite data at the pixel level, the precision of information from remote sensors is still less than desired. To fully release the power of phenological monitoring, surface phenology across a landscape needs to be observed and characterized in a well-planned manner. This study is characterizing spring plant phenology at the landscape scale, and preparing a methodological base that includes spatially distributed field observations, in order to facilitate more reliable and integrated phenological monitoring of vegetation dynamics. These in-situ data, as well as corresponding satellite data, soil survey data, DEMs, etc. will be analyzed with statistics, spatial analysis, geostatistics, and digital image processing techniques. This grant will support a second year spring field campaign and research equipment maintenance/improvement. This project will be among the first to incorporate substantial ground-level phenology at high temporal and spatial resolution to characterize plant phenology and biosphere-atmosphere interactions at the landscape level. The nature of these data will allow reasonable validation of satellite-derived phenological indices by bringing two scales of observation to the same resolution. This proposed study is thus also a pioneering work designed for exploring effective approaches to monitor regional to global scale biospheric responses to global change, through the bridging of spatial scales and synergistic integration of in-situ and remotely sensed phenological data.The student investigator will use this project to support completion of his doctoral dissertation. The data collected and methods tested will be useful for other graduate students and interested researchers to conduct follow-up and related studies (phenological observations will be shared through an Internet portal). Broadly, a better understanding of landscape phenology and biospheric responses to global climate change is important for enhancing scientific knowledge of earth systems in support of societal adaptation and sustainable development efforts.