Satellite Remote Sensing-Based In-Season Diagnosis of Rice Nitrogen Status in Northeast China

Remote Sensing

Shanyu Huang¹  Yuxin Miao¹  Guangming Zhao¹  Fei Yuan¹  Xiaobo Ma¹  Chuanxiang Tan¹  Weifeng Yu¹  Martin L. Gnyp¹  Victoria I.S. Lenz-Wiedemann¹  Uwe Rascher¹  Georg Bareth¹  Tao Cheng²  Zhengwei Yang²  Yoshio Inoue²  Yan Zhu²  Weixing Cao² 

[1] International Center for Agro-Informatics and Sustainable Development, College of Resources and Environmental Sciences, China Agricultural University, Beijing 100083, China; E-Mails:International Center for Agro-Informatics and Sustainable Development, College of Resources and Environmental Sciences, China Agricultural University, Beijing 100083, China;

关键词: satellite remote sensing;    nitrogen status diagnosis;    precision nitrogen management;    chlorophyll meter;    nitrogen nutrition index;    rice;    FORMOSAT-2;   

DOI  :  10.3390/rs70810646

来源: mdpi

【 摘 要 】

Rice farming in Northeast China is crucially important for China’s food security and sustainable development. A key challenge is how to optimize nitrogen (N) management to ensure high yield production while improving N use efficiency and protecting the environment. Handheld chlorophyll meter (CM) and active crop canopy sensors have been used to improve rice N management in this region. However, these technologies are still time consuming for large-scale applications. Satellite remote sensing provides a promising technology for large-scale crop growth monitoring and precision management. The objective of this study was to evaluate the potential of using FORMOSAT-2 satellite images to diagnose rice N status for guiding topdressing N application at the stem elongation stage in Northeast China. Five farmers’ fields (three in 2011 and two in 2012) were selected from the Qixing Farm in Heilongjiang Province of Northeast China. FORMOSAT-2 satellite images were collected in late June. Simultaneously, 92 field samples were collected and six agronomic variables, including aboveground biomass, leaf area index (LAI), plant N concentration (PNC), plant N uptake (PNU), CM readings and N nutrition index (NNI) defined as the ratio of actual PNC and critical PNC, were determined. Based on the FORMOSAT-2 imagery, a total of 50 vegetation indices (VIs) were computed and correlated with the field-based agronomic variables. Results indicated that 45% of NNI variability could be explained using Ratio Vegetation Index 3 (RVI3) directly across years. A more practical and promising approach was proposed by using satellite remote sensing to estimate aboveground biomass and PNU at the panicle initiation stage and then using these two variables to estimate NNI indirectly (R² = 0.52 across years). Further, the difference between the estimated PNU and the critical PNU can be used to guide the topdressing N application rate adjustments.

【 授权许可】

CC BY   
© 2015 by the authors; licensee MDPI, Basel, Switzerland.