期刊
NEW PHYTOLOGIST
卷 218, 期 1, 页码 119-130出版社
WILEY
DOI: 10.1111/nph.14927
关键词
diffusion; mass flow; nitrogen (N) immobilization; nitrogen uptake model; rhizosphere processes; root-microbe competition; root-nitrogen uptake; soil-nitrogen transport
资金
- Swedish Research Council for Environment, Agricultural Sciences and Spatial Planning
- Kempe Foundations
- Swedish University of Agricultural Sciences (SLU)
- Swedish Governmental Agency for Innovation Systems (Vinnova)
- Knut and Alice Wallenberg Foundation
The classic model of nitrogen (N) flux into roots is as a Michaelis-Menten (MM) function of soil-N concentration at root surfaces. Furthermore, soil-N transport processes that determine soil-N concentration at root surfaces are seen as a bottleneck for plant nutrition. Yet, neither the MM relationship nor soil-N transport mechanisms are represented in current terrestrial biosphere models. Processes governing N supply to roots - diffusion, mass flow, N immobilization by soil microbes - are incorporated in a model of root-N uptake. We highlight a seldom considered interaction between these processes: nutrient traverses the rhizosphere more quickly in the presence of mass flow, reducing the probability of its immobilization before reaching the root surface. Root-N uptake is sensitive to the rate of mass flow for widely spaced roots with high N uptake capacity, but not for closely spaced roots or roots with low uptake capacity. The results point to a benefit of root switching from high- to low-affinity N transport systems in the presence of mass flow. Simulations indicate a strong impact of soil water uptake on N delivery to widely spaced roots through transpirationally driven mass flow. Furthermore, a given rate of N uptake per unit soil volume may be achieved by lower root biomass in the presence of mass flow.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据