This review considers some of the mechanistic processes that involve roots in the soil nitrogen (N) cycle, and their implications for the ecological functions that retain N within ecosystems: 1) root signaling pathways for N transport systems, and feedback inhibition, especially for NO(3)(-) uptake; 2) dependence on the mycorrhizal and Rhizobium/legume symbioses and their tradeoffs for N acquisition; 3) soil factors that influence the supply of NH(4)(+) and NO(3)(-) to roots and soil microbes; and 4) rhizosphere processes that increase N cycling and retention, such as priming effects and interactions with the soil food web. By integrating information on these plant-microbe-soil N processes across scales and disciplinary boundaries, we propose ideas for better manipulating ecological functions and processes by which the environment provides for human needs, i.e., ecosystem services. Emphasis is placed on agricultural systems, effects of N deposition in natural ecosystems, and ecosystem responses to elevated CO(2) concentrations. This shows the need for multiscale approaches to increase human dependence on a biologically based N supply.

中文翻译：

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根、氮转化和生态系统服务

本综述考虑了土壤氮 (N) 循环中涉及根系的一些机制过程，以及它们对生态系统中保留氮的生态功能的影响：1) 氮传输系统的根信号通路和反馈抑制，尤其是对 NO (3)(-) 吸收；2) 对菌根和根瘤菌/豆科植物共生体的依赖及其对 N 获取的权衡；3) 影响NH(4)(+)和NO(3)(-)供给根系和土壤微生物的土壤因素；4) 增加氮循环和保留的根际过程，例如启动效应和与土壤食物网的相互作用。通过跨尺度和学科界限整合这些植物-微生物-土壤氮过程的信息，我们提出了更好地操纵生态功能和过程的想法，通过这些过程，环境可以满足人类的需求，即生态系统服务。重点放在农业系统、N 沉积在自然生态系统中的影响以及生态系统对 CO(2) 浓度升高的反应。这表明需要多尺度方法来增加人类对基于生物的氮供应的依赖。