Nitrates in the plant-soil systems: Sources, accumulation, potential risks and strategies to mitigate the accumulation

Abstract

In modern intensive agriculture, nitrogen (N) fertilizers are applied at high rates to enhance crop yield. However, the application of excessive fertilizers often exceeds crop uptake capacity, resulting in significantly reduced nitrogen use efficiency. This imbalance leads to substantial nitrate accumulation in soil-plant systems, posing severe risks: environmentally, it causes groundwater pollution via leaching; physiologically, it impacts crop quality and growth; and toxicologically, it threatens human health. This review systematically elucidates the dynamics of nitrate accumulation, categorizing sources and analyzing key driving factors, including environmental conditions and the regulation of nitrate transporters. Crucially, we critically evaluate the hazards and benefits of nitrate to both plants and humans, providing a balanced toxicological perspective. Furthermore, integrated mitigation strategies are outlined, ranging from optimizing fertilizer types and managing stabilized organic amendments to implementing runoff remediation technologies. Future perspectives emphasize the transition towards precision agriculture, utilizing sensors and Decision Support Systems (DSS) to align N input with crop demand curves, thereby balancing high productivity with environmental safety.