Collaborative research: Cascade “Ecohydromics” in the Amazonian Headwater System

合作研究：亚马逊河源头系统的级联“生态水文学”

• 批准号: 2106804
• 负责人: Scott Saleska
• 金额: $ 25.25万
• 依托单位: University of Arizona
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-01-01 至 2024-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2106804&HistoricalAwards=false
• 关键词: Collaborative; research; Cascade; Ecohydromics; Amazonian

Water movement through landscapes supports plant, animal, and human life, and through evaporation affects cloud processes and large-scale atmospheric circulation. The Amazon Basin cycles more water through streamflow and evaporation than any other contiguous forest in the world, and transpiration by trees – water taken up by roots and released to the atmosphere – is a critical part of this cycle. Understanding how plant roots, stems, and leaves interact with soil water to jointly regulate forest transpiration across landscapes is a critical knowledge gap, especially as climate changes. Forests are likely adapted to distinct soil moisture conditions in different parts of Amazonian landscapes. Specifically, forests on elevated plateaus with deep groundwater use water conservatively in order to tolerate drought, while those in wet valleys with shallow groundwater use water freely but may be poorly prepared for droughts of the future caused by the climate change. To understand landscape hydrology, rainforest compositions, and their susceptibility to global change, an integrated understanding of how water flows are regulated from upstream-to-downstream by plants and soil is required. This understanding is also critical for Earth-system modeling used to project the fate of Amazonian rainforests and quantify their future influence on climate. This project links diverse disciplines – plant physiology, ecology, hydrology – and integrates them into a model of landscape function. This project will also help train the next generation of scientists, both in the U.S. and Brazil, on interdisciplinary approaches in research, and through a summer school on computer modeling of vegetation and hydrologic processes. The project will develop a novel science outreach program connecting K-12 students to real-time Amazon tree data as well as a short class curriculum and a series of videos that teach students how to interpret data, understand the broader scientific context, and build a personal connection with scientists and real-time “talking trees” from the world’s most famous tropical forest.This project characterizes landscape variation in physiological and hydrological processes, and integrate observations with watershed modeling and hypothesis testing. Project activities focus on the spatially intricate mosaic of plateaus and valleys characteristic of central Amazonian headwater catchments. This research hypothesizes that: (H1) strong landscape variation in forest transpiration capacity arises from distinct characteristics of trees residing on plateaus (no root access to groundwater) and valleys (root access to groundwater) zones; (H2) previously unquantified “hybrid” soil hydraulics govern soil water fluxes and transit times connecting plateaus and valleys; and (H3) plateau forests influence the composition and function of valley forests by regulating subsurface water flows from higher to lower landscape areas. Study sites are located in the Brazilian Amazon: “KM34” near Manaus contains an instrumented watershed with more historical data and research on hillslope hydrology than any other watershed in a pristine wet tropical forest, and “KM67” near Santarém sits on a broad plateau with previously deployed deep soil moisture pits, allowing the isolation of processes typical for flat, elevated plateaus. Both sites contain eddy flux towers, canopy access walkways, and a rich history of ecological research and available datasets. A new valley subsite near KM67 will serve as an independent replicate of KM34 observations in valleys. Process-based models of vegetation ecophysiology, subsurface hydrology, and groundwater will be parameterized with observations of leaf physiology, tree morphological traits, soil moisture and physical properties, water table, and streamflow. These models will be integrated employing novel tools in probabilistic learning and uncertainty quantification for proper parameterization and validated with independent observations of tree sapflow, and ecosystem gas exchange and energy balance.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.

景观中的水运动支持植物、动物和人类的生命，并通过蒸发影响云过程和大规模大气环流，亚马逊盆地通过水流和蒸发循环的水量比世界上任何其他邻近的森林以及树木的蒸腾作用都要多。根部吸收水分并释放到大气中是这个循环的关键部分，了解植物根、茎和叶如何与土壤水相互作用以共同调节整个景观的森林蒸腾作用是一个关键的知识缺口，尤其是在气候变化的情况下。亚马逊流域不同地区的森林可能会适应不同的土壤湿度条件，具体而言，具有深层地下水的高原上的森林会保守地使用水以耐受干旱，而具有浅层地下水的潮湿山谷中的森林则可以自由地使用水，但可能会受到影响。对气候变化造成的未来干旱准备不足 为了了解景观水文、雨林组成及其对全球变化的敏感性，需要对植物和土壤如何从上游到下游调节水流进行综合理解。这种理解对于用于预测亚马逊雨林的命运并量化其未来对气候的影响的地球系统模型也至关重要，该模型涉及不同的学科——植物生理学、生态学、水文学——并将它们整合到景观功能模型中。该项目还将帮助培训美国和巴西的下一代科学家进行跨学科研究方法，并通过植被和水文过程的计算机建模暑期学校该项目将开发一个连接 K 的新颖的科学推广计划。 -12向学生提供实时亚马逊树数据以及简短的课程和一系列视频，教学生如何解释数据，了解更广泛的科学背景，并与科学家和实时“会说话的树”建立个人联系世界上最著名的热带森林。该项目描述了生理和水文过程中的景观变化，并将观测与流域建模和假设检验相结合。该项目活动的重点是亚马逊河源头流域的空间复杂的高原和山谷特征。那： (H1) 森林蒸腾能力的强烈景观变化源于居住在高原（没有根部接触地下水）和山谷（根部接触地下水）区域的树木的独特特征；(H2) 以前未量化的“混合”土壤水力学控制土壤水通量；连接高原和山谷的运输时间；(H3) 高原森林通过调节从较高地势区域到较低地势区域的地下水流来影响山谷森林的组成和功能 研究地点位于巴西亚马逊地区：马瑙斯附近的“KM34”包含一个仪器化流域，比原始潮湿热带森林中的任何其他流域都拥有更多的历史数据和山坡水文研究，而圣塔伦附近的“KM67”坐落在广阔的高原上，之前部署了深层土壤湿度坑，允许平坦、高架高原的典型过程隔离。两个地点都包含涡流塔、树冠通道以及丰富的生态研究历史和可用数据集。 KM67 将作为 KM34 山谷观测数据的独立复制，基于过程的植被生态生理学、地下水文学和地下水模型将通过对叶子生理学、树木形态特征、土壤湿度和物理特性、地下水位和水流的观测进行参数化。这些模型将采用概率学习和不确定性量化的新颖工具进行集成，以进行适当的参数化，并通过对树木液流、生态系统气体交换和能量平衡的独立观察进行验证。该奖项反映了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，NSF 的法定使命被认为值得支持。

项目成果

The role of ecosystem transpiration in creating alternate moisture regimes by influencing atmospheric moisture convergence

生态系统蒸腾作用通过影响大气水分收敛来创造替代水分状况

• DOI: 10.1111/gcb.16644
• 发表时间: 2022-05-29
• 期刊: Global Change Biology
• 影响因子: 11.6
• 作者: A. Makarieva;A. Nefiodov;A. Nobre;M. Baudena;U. Bardi;D. Sheil;S. Saleska;R. D. Molina;A. Rammig
• 通讯作者: A. Rammig