Feedbacks between soil penetration resistance, root architecture and water uptake limit water accessibility and crop growth - A vicious circle
Feedbacks between soil penetration resistance, root architecture and water uptake limit water accessibility and crop growth - A vicious circle
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DOI：
10.1016/j.scitotenv.2018.01.129
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发表时间：
2018-06-01
影响因子：
9.8
通讯作者：
Keller, Thomas
中科院分区：
文献类型：
--
作者：
Colombi, Tino;Torres, Lorena Chagas;Keller, Thomas
水是全球作物生产的最大限制性资源。由于气候变化，预计干旱期将增加，这将进一步加剧受水限制的作物产量问题。除了水资源丰富度和可用性低之外，水资源有限也是由于水资源有限造成的。土壤渗透阻力主要受土壤水分的影响，是调节根系伸长和水分可及性的主要土壤性质。土壤渗透阻力、根系特性、水分吸收和作物生产力之间的相互作用目前还很少研究。在目前的研究中，我们量化了土壤渗透阻力，根系构型和水分吸收之间的相互作用如何影响田间水分可及性和作物生产力。玉米种植在压实和未压实的土壤，无论是翻耕或压实后保持不翻耕，这导致了四个处理具有不同的表土渗透阻力。较高的表土渗透阻力导致根系较浅。这导致从表层土壤中吸收的水分增加，从而导致表层土壤干燥，这进一步增加了最上层土壤的渗透阻力。由于这种反馈，根系生长到更深的土壤层，那里本来是有水的，减少了，植物生长下降。我们的研究结果表明，土壤渗透阻力，根系构型和水分吸收是密切相关的，从而决定了潜在的植物进入土壤蓄水池。因此，这些相互作用及其对水的可获得性和作物生产力的反馈，必须考虑到制定战略，以减轻种植系统中的水限制。(C)2018爱思唯尔B.V.保留所有权利。
Water is the most limiting resource for global crop production. The projected increase of dry spells due to climate change will further increase the problem of water limited crop yields. Besides low water abundance and availability, water limitations also occur due to restricted water accessibility. Soil penetration resistance, which is largely influenced by soil moisture, is the major soil property regulating root elongation and water accessibility. Until now the interactions between soil penetration resistance, root system properties, water uptake and crop productivity are rarely investigated. In the current study we quantified how interactive effects between soil penetration resistance, root architecture and water uptake affect water accessibility and crop productivity in the field. Maize was grown on compacted and uncompacted soil that was either tilled or remained untilled after compaction, which resulted in four treatments with different topsoil penetration resistance. Higher topsoil penetration resistance caused root systems to be shallower. This resulted in increased water uptake from the topsoil and hence topsoil drying, which further increased the penetration resistance in the uppermost soil layer. As a consequence of this feedback, root growth into deeper soil layers, where water would have been available, was reduced and plant growth decreased. Our results demonstrate that soil penetration resistance, root architecture and water uptake are closely interrelated and thereby determine the potential of plants to access soil water pools. Hence, these interactions and their feedbacks on water accessibility and crop productivity have to be accounted for when developing strategies to alleviate water limitations in cropping systems. (C) 2018 Elsevier B.V. All rights reserved.