Quantifying the importance of deep and shallow roots for plant water use and redistribution using a novel cave system to 20 m depth

该奖项是根据《2009年美国复苏和再投资法案》(公法111-5)提供资金的。吸收水分对树木、草和农作物的生长和生存至关重要，特别是在干旱和炎热的夏季。虽然许多科学家已经研究了从地面到树顶的水分吸收和运动，但在大多数物种和生态系统中，一半或更多的植物仍然没有得到研究。这项提议的目标是比较美国南部生长的树木深根(地下5-20米)和浅根的功能。它使用德克萨斯州中部的PI开发的一种新的洞穴系统来研究地下的树根，并使用基于分子的指纹对这些根进行匹配，将它们与各自的浅层对应根进行匹配，很像侦探使用的法医方法。研究问题包括：1)树木消耗的水分有多少来自地下深处？2)深层根系促进水分运输的独特物理特性是什么？3)植物中特殊的水分通道在多大程度上有助于它们吸收和运输水分？拟议的活动为社会提供了许多潜在的好处，包括测量美国中部地下水的使用和树木的补给。为了推广和培训，杰克逊实验室在过去五年里让30多名本科生和9名高中生(其中3名是少数族裔)参与了NSF资助的研究。杰克逊还与当地高中进行了广泛的接触，包括在北卡罗来纳州罗利市布劳顿高中的8个环境研究班任教，以及在北卡罗来纳州High Point的High Point高中的环境科学班授课。

This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5).The uptake of water is essential for trees, grasses, and crops to grow and survive, particularly during droughts and hot summer months. While many scientists have studied water uptake and movement from the ground to the top of trees, half or more of plants remains unstudied in most species and ecosystems. The goal of this proposal is to compare the functioning of deep (5-20 meters underground) and shallow roots for trees growing in the southern United States. It uses a novel cave system developed by the PIs in central Texas to study tree roots underground and uses molecular-based fingerprinting of these roots to match them to their respective shallow counterparts, much like the forensic approaches that detectives use. The research questions include, 1) How much water that trees use comes from deep underground? 2) What are the unique physical characteristics of deep roots that promote water transport? and 3) To what extent do specialized water channels in plants contribute to their ability to take up and transport water? The proposed activities provide numerous potential benefits to society, including measurements of groundwater use and recharge by trees in the central U.S. For outreach and training, the Jackson lab has involved more than 30 undergraduate students and nine high school students (three of them minorities) in NSF-funded research in the last five years. Jackson has also done extensive outreach with local high schools, including teaching in 8 Environmental Studies classes at Broughton High School in Raleigh, NC and mentoring in an environmental science class at High Point High School in High Point, NC.