Network Cluster: Patterns and controls of ecohydrology, CO2 fluxes, and nutrient availability in pedogenic carbonate-dominated dryland critical zones

网络集群：成土碳酸盐主导的旱地关键区域的生态水文学、二氧化碳通量和养分可用性的模式和控制

• 批准号: 2012475
• 负责人: Lixin Jin
• 金额: $ 526.93万
• 依托单位: University of Texas at El Paso
• 依托单位国家: 美国
• 项目类别: Cooperative Agreement
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-09-01 至 2025-08-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2012475&HistoricalAwards=false
• 关键词: Network; Cluster; Patterns; controls; ecohydrology

The Critical Zone is the layer of Earth’s surface from the top of the trees to the bottom of the groundwater. Rocks, soil, water, air, and living organisms interact in the Critical Zone to provide life-sustaining resources such as food and water. Drylands, with arid to semi-arid climates, cover 45% of the Earth and provide homes to more than 2 billion people. The drylands of the American West are facing significant challenges caused by global change, such as drought and changing plant communities. Increases in human population and food demand have also converted many natural drylands in this region to irrigated farms. These changes in land use and climate have greatly affected the movement of water, carbon, nutrients and salt through different parts of the drylands. All of these changes impact the sustainability of natural and agricultural ecosystems. This project will investigate these important Critical Zone processes and improve our ability to predict future change. Specifically, this thematic cluster will investigate how carbonate minerals in dryland soils control and impact water, nutrients, salts, and carbon moving in and out of the Critical Zone. This project will help to educate and train middle to high school students, and college undergraduate and graduate students. These students will be provided with the motivation, skills and tools to become future professionals in science, technology, engineering, arts, and mathematics (STEAM). Our research and education efforts will also help to grow public awareness of the importance of the Critical Zone function and service in drylands.The Critical Zone in dryland ecosystems is an understudied but crucial part of the Earth system. It contrasts with mesic areas by having sparse vegetation, limited but dynamic soil moisture, deep water table, low soil organic matter, alkaline pH, and buildup of salt precipitates, especially as pedogenic carbonates that can develop into a thick caliche layer and dominate the soil structure. However, these systems are underrepresented in Critical Zone research and current conceptual models do not fully address phenomena unique to drylands such as development of pedogenic carbonate, dust storms, episodic precipitation, and high spatiotemporal variability in hydrological and biogeochemical processes. To fill these knowledge gaps, the overarching goal of the project is to increase our capacity to quantify and predict dryland carbon budgets across land-use and climatic gradients by examining the role of water and nutrient availability in regulating the movement of organic and inorganic carbon in the dryland Critical Zone. Specifically, this project centers around the multifaceted roles of pedogenic carbonates in dictating vadose zone water dynamics, the potential recharge to deep water table, and nutrient cycling in typical dryland landscapes, piedmont, playa and irrigated agricultural fields. These in turn drive trends in evolution of Critical Zone architectures and land-atmosphere C exchange. We will tackle these problems by using a comprehensive set of tools including eddy covariance towers, deep Critical Zone drilling, hydrogeophysical surveys, soil and hydrologic sensors, isotopic analysis, synchrotron, geochemical proxies, and genetic sequencing. This project builds on the rich historical data, knowledge, and models at the Jornada LTER, the Reynolds Creek CZO, USDA-ARS Kimberly site in Idaho and irrigated agricultural sites along the Rio Grande Valley in Texas. This thematic cluster will develop an interdisciplinary framework to understand material and energy flow through dryland Critical Zones and lay the foundation for managing Critical Zone function, evolution, and services, as well as forecasting carbon budget changes with future shifts in climate and land use in drylands.This project is jointly funded by the Critical Zone Collaborative Network and the Hydrologic Sciences programs in the Division of Earth Sciences and the Hispanic Serving Institutions program in the Education and Human Resources Directorate's Division of Human Resource Development.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.

临界区是指地球表面从树木顶部到地下水底部的那一层。岩石、土壤、水、空气和生物在临界区内相互作用，提供食物和水等维持生命的资源。旱地气候干旱至半干旱，覆盖了地球45%的面积，为20多亿人提供了家园。美国西部的旱地正面临着由全球变化造成的重大挑战，如干旱和植物群落的变化。人口和粮食需求的增加也使该地区的许多天然旱地变成了灌溉农场。土地利用和气候的这些变化极大地影响了水、碳、养分和盐分在旱地不同地区的流动。所有这些变化都会影响自然和农业生态系统的可持续性。该项目将调查这些重要的关键区流程，并提高我们预测未来变化的能力。具体地说，这一专题组将调查旱地土壤中的碳酸盐矿物如何控制和影响进出临界区的水、养分、盐和碳。该项目将有助于教育和培养初中生、大学本科生和研究生。这些学生将获得成为未来科学、技术、工程、艺术和数学(STEAM)专业人员的动力、技能和工具。我们的研究和教育工作也将有助于提高公众对旱地临界区功能和服务的重要性的认识。旱地生态系统的临界区是地球系统中一个研究不足但至关重要的部分。它与中生区相比，植被稀少，土壤水分有限但动态，地下水位深，土壤有机质低，碱性pH低，盐分沉淀堆积，特别是作为成壤碳酸盐，可以发育成厚厚的钙质层，并主导土壤结构。然而，这些系统在临界区研究中的代表性不足，目前的概念模型没有完全解决旱地特有的现象，例如成壤碳酸盐的发育、沙尘暴、阶段性降水以及水文和生物地球化学过程中的高度时空变异性。为了填补这些知识空白，该项目的总体目标是通过研究水和养分在调节旱地临界地带有机碳和无机碳移动中的作用，提高我们量化和预测不同土地利用和气候梯度的旱地碳收支的能力。具体地说，该项目围绕成壤碳酸盐在决定包气带水动态、向深层地下水位的潜在补给以及典型旱地景观、山前、普拉亚和灌溉农田的养分循环中的多方面作用展开。这些反过来又推动了临界区架构和陆地-大气C交换的演变趋势。我们将通过使用一套全面的工具来解决这些问题，包括涡旋协方差塔、深层临界区钻探、水文地球物理调查、土壤和水文传感器、同位素分析、同步加速器、地球化学物和基因测序。该项目建立在Jornada LTER、Reynolds Creek CZO、爱达荷州USDA-ARS金伯利基地和德克萨斯州格兰德河谷沿岸灌溉农业场地的丰富历史数据、知识和模型的基础上。该专题组将开发一个跨学科框架，以了解旱地关键区域的物质和能量流动，为管理关键区域的功能、演化和服务，以及预测未来旱地气候和土地利用变化的碳预算变化奠定基础。该项目由关键区域合作网络和地球科学部门的水文科学计划以及教育和人力资源委员会人力资源发展部门的拉美裔服务机构计划共同资助。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。