Abstract: Nitrogen is one of the essential nutrients for crop growth. The deficiency or surplus of nitrogen can seriously affect crop yield and economic benefit. Timely, accurate and damage-free monitoring crop nitrogen content is of great significance for crop yield increase, rational fertilization and reduction of environmental pollution. This paper summarized the remote sensing estimation principle of crop nitrogen content, concluded the estimation methods and research progress at home and abroad. On this basis, the paper analyzed the problems existing in crop nitrogen content estimation based on remote sensing spectral data. The key points for future research was put forward, such as the improvement of model universality, the use of multi-source remote sensing data, and the monitoring of crop nitrogen content under influence of multi-factor.

Key words: remote sensing, nitrogen content, model, overview

摘要： 氮是作物生长不可或缺的营养物质之一，氮的亏缺或富余会严重影响作物的产量和经济效益，及时、准确和无损的作物氮素水平监测对作物的增产、合理施肥以及减少环境污染等具有重要意义。阐述了作物氮含量遥感估算的原理及国内外估算方法与研究进展，并在此基础上分析了基于遥感光谱数据的作物氮含量估算存在的问题，提出了未来研究的重点：模型普适性的提高、多源遥感数据的使用、多因素影响下作物氮含量的监测等。

关键词: 遥感, 氮含量, 模型, 综述