CAREER: Ecohydrological controls on land-atmosphere interactions in water-limited ecosystems: a framework for education and research

受水限制的生态系统对降水变化特别敏感，随着气候和其他全球变化继续改变这些生态系统中的水可获得性，了解陆地-大气相互作用的控制及其如何影响更大规模的反馈将变得越来越重要。尽管水有限的生态系统占地球陆地表面的比例相对较大，但在陆地表面和全球循环模型中的代表性很差。这项研究将利用简单的概念框架与遥感产品相结合的建模方法，将实地调查的小规模过程和实验工作与大规模过程联系起来，解决水有限的生态系统功能问题。十多年的实地工作突出了深层土壤水分在缺水生态系统运行中的重要性。关于深层土壤水分在缺水生态系统中的作用的新假设将使用一个基于两个土层(例如表层：0-20厘米，深层：20-60厘米)水分的简单框架来处理。这个健壮的框架非常适合在教育和研究环境中开发和测试假设。此外，该项目将使用该框架在其他独特的水资源有限的生态系统(例如，依赖雪的亚高山、北极冻土带)中测试假设。从地块到生态系统规模的调查结果将用于支持更大规模的假设检验，采用能够覆盖多层水分并结合遥感产品的建模方法。全球近40%的陆地表面被归类为干旱至半干旱；根据当前的气候趋势，这个比例几乎肯定会增加。从历史上看，这些缺水地区也是人口大量增加的地方。持续的气候变化和人口增长的这种有问题的组合给当地生态系统造成了根本性的变化，这无疑将对流域和河流产生重大影响；这些影响可能会进一步加剧气候变化。这项研究强调对水资源有限的生态系统进行监测，以更好地预测这些生态系统在全球变化下的行为和功能，并更好地了解它们对全球水、碳和能源循环的贡献。此外，该项目将让学生(特别是贫困和代表性不足的学生)参与科学进程，作为一种手段，让他们为就业做好准备。这一点尤其重要，因为越来越需要培训学生向公众有效地传达科学研究的重要性。这项研究中强调的简单的两层水分框架是解决这些综合研究和教育挑战的理想选择。

Water-limited ecosystems are especially sensitive to precipitation changes, and understanding the controls on land-atmosphere interactions and how they influence larger scale feedbacks will become increasingly important as climatic and other global changes continue to alter the water availability in these ecosystems. Despite comprising a relatively large percentage of the Earth's land surface, water-limited ecosystems are poorly represented in land-surface and global circulation models. This research will address water limited ecosystems function by linking small scale processes investigated in field and experimental efforts with large scale processes using a modeling approach that takes advantage of a simple conceptual framework combined with remote sensing products. Over a decade of field work has highlighted the importance of deep soil moisture in the functioning of water-limited ecosystems. Emergent hypotheses on the role of deep soil moisture in water-limited ecosystems will be addressed using a simple framework based on moisture in two soil layers (e.g. surface layer: 0 - 20 cm, deep layer: 20 - 60 cm). This robust framework is ideal for developing and testing hypotheses in both educational and research settings. Furthermore, the project will use this framework to test hypotheses in other uniquely water-limited ecosystems (e.g. snow-dependent subalpine, arctic tundra). Plot- to ecosystem- scale findings will be used to support hypothesis testing at larger scales using a modeling approach capable of multiple layers of moisture and incorporating remote sensing products. Nearly 40% of the global land surface is classified as arid to semiarid; a percentage that is almost certain to increase based on current climate trends. Historically, these water-limited areas have also been locations of major population increase. This problematic combination of sustained climate change and population growth creates fundamental changes to native ecosystems that will undoubtedly have major impacts on watersheds and rivers; these impacts are likely to exacerbate further climatic changes. This research emphasizes monitoring in water-limited ecosystems to better predict the behavior and functioning of these ecosystems under global change and also better understand their contribution to global water, carbon, and energy cycling. Further, the project will engage students (especially underprivileged and underrepresented students) in the process of science as a means to ready them for the workforce. This is particularly crucial with the growing need to train students to effectively communicate the importance of scientific research to the general public. The simple two-layer moisture framework highlighted in this research is ideal for tackling both of these integrated research and educational challenges.