A dual porosity model of nutrient uptake by root hairs
A dual porosity model of nutrient uptake by root hairs
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DOI：
10.1111/j.1469-8137.2011.03840.x
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发表时间：
2011-01-01
期刊：
影响因子：
9.4
通讯作者：
Roose, T.
中科院分区：
文献类型：
--
作者：
Zygalakis, K. C.;Kirk, G. J. D.;Roose, T.
根毛在微溶养分吸收的重要性是定性的理解，但不是定量的，这限制了努力培育植物的耐养分缺乏soil.Here，我们开发了一个数学模型的营养吸收根毛允许头发的几何形状和细节的养分运输通过土壤，包括扩散内和土壤颗粒之间。与传统的“单孔隙度”模型相比，这种“双孔隙度”模型预测更大的根系吸收，因为更多的养分是通过缓慢释放从土壤颗粒内。此外，土壤水分的影响是不太重要的双孔隙度模型，因为在土壤中的扩散的有效体积是较大的，和预测的影响头发的长度和密度是不同的，与实验观察一致，与双孔隙度模型，头发长度的增加，得到更大的增加吸收比增加头发密度每单位主根长度。在干燥土壤中，毛密度的影响较小，因为溶液中达到净流入的最小浓度更快。头发长度的影响对土壤湿度的敏感性要小得多。
The importance of root hairs in the uptake of sparingly soluble nutrients is understood qualitatively, but not quantitatively, and this limits efforts to breed plants tolerant of nutrient-deficient soils.Here, we develop a mathematical model of nutrient uptake by root hairs allowing for hair geometry and the details of nutrient transport through soil, including diffusion within and between soil particles. We give illustrative results for phosphate uptake.Compared with conventional 'single porosity' models, this 'dual porosity' model predicts greater root uptake because more nutrient is available by slow release from within soil particles. Also the effect of soil moisture is less important with the dual porosity model because the effective volume available for diffusion in the soil is larger, and the predicted effects of hair length and density are different.Consistent with experimental observations, with the dual porosity model, increases in hair length give greater increases in uptake than increases in hair density per unit main root length. The effect of hair density is less in dry soil because the minimum concentration in solution for net influx is reached more rapidly. The effect of hair length is much less sensitive to soil moisture.