Maturity monitoring of wheat demonstration fields in Chang'an District, Xi'an

With the continuous advancement of technology, precision agriculture has become an important development direction for modern agriculture. Precision agriculture is an agricultural production model based on modern information technology. By accurately acquiring, analyzing, and applying farmland information, it enables effective monitoring and management of the farmland environment, crop growth, and pests and diseases, thereby improving agricultural production efficiency and the quality of agricultural products. In this process, hyperspectral remote sensing technology plays a crucial role.

Hyperspectral monitoring technology helps precision agriculture

Hyperspectral remote sensing, also known as imaging spectral remote sensing, refers to the technology of acquiring a wide range of very narrow and continuous spectral image data in the visible, near-infrared, mid-infrared, and thermal infrared regions of the electromagnetic spectrum. Its bandwidth is generally less than 10 nm, thus obtaining more continuous and complete spectral information, covering a wider spectral range, accurately distinguishing crop types, and monitoring various agronomic parameters of crops.

The application of hyperspectral remote sensing technology in precision agriculture is mainly reflected in the rapid, non-destructive, and accurate monitoring of crop growth, physiological and biochemical characteristics, yield, and quality using hyperspectral remote sensing data, providing technical support for the scientific management and high-yield and high-efficiency management of crops.

Xi'an Institute of Optics and Precision Mechanics CAS Aerospace Science and Technology Group Co.,LTD - Wheat Maturity Monitoring

Wheat (Triticum aestivum) is a major global food crop, with approximately 35%–40% of the world's population relying on it as a staple food. As a populous country, my country's demand for wheat has consistently remained high. In recent years, market competition and changes in arable land quality have led to significant fluctuations in wheat production. Wheat production is crucial to my country's food security, economic development, and social stability; timely information on wheat production can provide a scientific basis for national economic and macroeconomic decision-making.

To rapidly and accurately monitor wheat maturity and rationally determine harvest time, this study used wheat from a demonstration field in Chang'an District as the research object. UAV RGB and multispectral images of the experimental area were acquired during the mid-to-late grain-filling stage. Lab space transformation was performed on the RGB images to extract the 'a' component values, and the changing characteristics of wheat grain maturation were analyzed. The 'a' values ​​of wheat from the grain formation stage to the milk stage were normalized to construct a maturity monitoring index (MCI). The spectral characteristics of wheat at different maturity levels were analyzed through multispectral imagery. Based on optimized band features, the ratio vegetation index (RVI) and normalized difference vegetation index (NDVI) were selected as independent variables for MCI inversion, respectively, to construct a wheat maturity monitoring model.

The following figure shows the results of the inversion of wheat maturity before harvest in a wheat demonstration field in Chang'an District, Shaanxi Province. On May 22, the monitored area was approximately 1254.36 mu, of which the relatively mature area was approximately 227.42 mu, accounting for 18.13% of the total area.

Hyperspectral remote sensing technology can accurately obtain detailed spectral information of plants and establish monitoring models, thereby enabling precise monitoring of crop type and sown area, crop growth environment and pests and diseases, crop physiological and biochemical traits, crop growth, yield and quality, etc., promoting scientific management of agriculture and achieving high yield and quality, and playing a positive role in promoting the development of precision agriculture.