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Collaborative Proposal: MSB-FRA: Improved Understanding of Feedbacks between Ecosystem Phenology and the Weather-Environment Nexus at Local-to-Continental Scales

合作提案：MSB-FRA：提高对地方到大陆尺度生态系统物候学与天气环境关系之间反馈的理解

基本信息

批准号：
1702627
负责人：
Mark Friedl
金额：
$ 39.58万
依托单位：
Trustees of Boston University
依托单位国家：
美国
项目类别：
Standard Grant
财政年份：
2017
资助国家：
美国
起止时间：
2017-08-15 至 2023-07-31
项目状态：
已结题

来源：
https://www.nsf.gov/awardsearch/showAward?AWD_ID=1702627&HistoricalAwards=false
关键词：
Collaborative Proposal MSB FRA Improved

项目摘要

Phenology--the rhythm of the seasons--drives the progression of vegetation through its annual cycles from dormancy to activity and back to dormancy. Phenology is thus critical for many ecological processes. It also directly influences ecosystem productivity and the production of many goods and ecosystem services on which human society is reliant. Importantly, phenological rhythms are highly sensitive to year-to-year variability in weather, but they can also in turn influence weather itself. Thus, there are feedbacks between terrestrial ecosystems and the atmosphere that are phenologically-controlled. This project will use imagery from a network of digital cameras--the PhenoCam Network--to track vegetation phenology at high spatial and temporal resolution across North America, from tundra to the tropics. Together with sophisticated computer simulations, this project will then investigate phenologically-controlled ecosystem-atmosphere feedbacks across a climatic gradient from the Southwest, through the Great Plains, and into the Northeastern US. The question this project seeks to answer is, How much influence do these feedbacks have on how ecosystems work, and at what spatial and temporal scales? This question is important from the point of view of managing and sustaining healthy ecosystems. Public participation in scientific research will be achieved through collaboration with the Harvard Forest Long-Term Ecological Research Project's Schoolyard program and the Summer Research Program. Through these efforts this project will contribute to the education and training of traditionally under-represented groups. This project additionally includes interdisciplinary training and research opportunities for graduate-level students and three postdoctoral research associates. Imagery and data from PhenoCam will continue to be made publicly available, in near-real time, for research and education.This project strives to understand the role of phenology in mediating ecosystem-atmosphere coupling and feedbacks at multiple spatial and temporal scales. The researchers will apply a macrosystems approach by integrating simulation models and observational data to investigate cross-scale interactions and emergent phenomena. First, they will use data from the PhenoCam network, a continental-scale phenological observatory, to develop improved models of vegetation phenology. Then, they will conduct a hierarchy of computer simulation experiments to investigate interactions between terrestrial ecosystems and the atmosphere/climate system that are controlled by phenology. Specifically, this project investigates: (1) How does phenology regulate the strength of ecosystem-atmosphere coupling across a continental-scale ecoclimatic gradient? (2) How does the seasonality of ecosystem-atmosphere coupling vary within and across this gradient? and, (3) How do coupled ecosystem-atmosphere dynamics influence ecosystem function at local to continental spatial scales and seasonal to interannual timescales? The researchers will derive phenological metrics by applying image analysis methods to time series of digital camera images from PhenoCam. Formal model selection criteria will be used to test and evaluate different model structures for the phenology of key plant functional types. The researchers will tackle their key science questions using a sophisticated earth system model with prescribed and prognostic phenology scenarios. These analyses will be complemented by empirical, data-driven analyses fusing PhenoCam data, satellite remote sensing, daily meteorological data and gridded reanalysis products, and micrometeorological measurements of ecosystem-atmosphere fluxes of CO2, water and energy from AmeriFlux sites. Camera and flux data from NEON sites will be incorporated as these become available. Broader impacts from this project will target formal and informal science education, the development of scientific infrastructure, and training of the next generation of interdisciplinary earth system scientists.

物候——季节的节奏——驱动植被通过从休眠到活动再回到休眠的年度周期的进展。因此，物候对于许多生态过程至关重要。它还直接影响生态系统生产力以及人类社会所依赖的许多商品和生态系统服务的生产。重要的是，物候节律对每年的天气变化高度敏感，但它们也会反过来影响天气本身。因此，陆地生态系统和大气之间存在受物候控制的反馈。该项目将使用来自数码相机网络（PhenoCam 网络）的图像，以高空间和时间分辨率跟踪整个北美（从苔原到热带地区）的植被物候学。结合复杂的计算机模拟，该项目将研究从西南地区到大平原，再到美国东北部整个气候梯度的物候控制生态系统大气反馈。该项目试图回答的问题是，这些反馈对生态系统如何运作以及在什么空间和时间尺度上有多大影响？从管理和维持健康生态系统的角度来看，这个问题很重要。公众对科学研究的参与将通过与哈佛森林长期生态研究项目的校园计划和夏季研究计划的合作来实现。通过这些努力，该项目将为传统上代表性不足的群体的教育和培训做出贡献。该项目还包括为研究生和三名博士后研究员提供跨学科培训和研究机会。来自 PhenoCam 的图像和数据将继续近乎实时地向公众提供，用于研究和教育。该项目致力于了解物候学在多个时空尺度上调节生态系统-大气耦合和反馈中的作用。研究人员将通过整合模拟模型和观测数据来应用宏观系统方法来研究跨尺度相互作用和涌现现象。首先，他们将使用来自大陆规模物候观测站 PhenoCam 网络的数据来开发改进的植被物候模型。然后，他们将进行一系列计算机模拟实验，以研究陆地生态系统与受物候控制的大气/气候系统之间的相互作用。具体来说，该项目研究：（1）物候如何调节整个大陆尺度生态气候梯度的生态系统-大气耦合强度？ (2) 生态系统-大气耦合的季节性在该梯度内和梯度之间如何变化？ (3) 耦合的生态系统-大气动态如何影响局部到大陆空间尺度以及季节到年际时间尺度的生态系统功能？研究人员将通过对 PhenoCam 数码相机图像的时间序列应用图像分析方法来得出物候指标。正式的模型选择标准将用于测试和评估关键植物功能类型物候的不同模型结构。研究人员将使用具有规定和预测物候场景的复杂地球系统模型来解决他们的关键科学问题。这些分析将得到融合 PhenoCam 数据、卫星遥感、每日气象数据和网格再分析产品的实证数据驱动分析，以及来自 AmeriFlux 站点的二氧化碳、水和能量生态系统-大气通量的微气象测量。来自 NEON 站点的相机和通量数据将在可用时纳入其中。该项目的更广泛影响将针对正式和非正式的科学教育、科学基础设施的发展以及下一代跨学科地球系统科学家的培训。

项目成果

期刊论文数量（33）

专著数量（0）

科研奖励数量（0）

会议论文数量（0）

专利数量（0）

Evaluation of land surface phenology from VIIRS data using time series of PhenoCam imagery

DOI：
10.1016/j.agrformet.2018.03.003
发表时间：
2018-06
期刊：
Agricultural and Forest Meteorology
影响因子：
6.2
作者：
Xiaoyang Zhang;Senthilnath Jayavelu;Lingling Liu;M. Friedl;G. Henebry;Yan Liu;C. Schaaf;A. Richardson;Joshua Gray
通讯作者：
Xiaoyang Zhang;Senthilnath Jayavelu;Lingling Liu;M. Friedl;G. Henebry;Yan Liu;C. Schaaf;A. Richardson;Joshua Gray

Senescence in temperate broadleaf trees exhibits species-specific dependence on photoperiod versus thermal forcing

温带阔叶树的衰老表现出对光周期与热强迫的物种特异性依赖性