Abstract:

Real−time monitoring of the growth and harvesting progress of major grain crops (corn, rice and soybean) is crucial for national food security and precise smart agricultural services. Based on remote sensing images and agricultural observation data, this study established a self−developed crop growth grading model (CGG) and harvest monitoring model (HM) by combining the ten−day and daily normalized difference vegetation index (NDVI) datasets in the major grain−producing areas of Heilongjiang province from 2019 to 2023. These models were applied to analyze the spatiotemporal evolution characteristics of major grain crop growth and harvest areas, aiming to improve the capability of regional smart meteorological services in guaranteeing food security and boosting regional agricultural development. The results showed that: (1) the self−developed CGG and HM models could effectively identify the growth status and harvesting conditions of major grain crops in the study area from 2019 to 2023, with an overall mean absolute percentage error (MAPE) lower than 25.0%. (2) Simulations via the CGG model revealed a significant year−by−year improvement in the growth of major grain crops in the major grain−producing areas of Heilongjiang Province from 2019 to 2023. During the crop growing season of 2023, the periods with excellent and poor growth status accounted for 43.3% and 8.3% of the entire growing season, respectively. (3) Based on the HM model, by late October from 2019 to 2023, most areas of the major grain−producing areas in Heilongjiang province had completed the harvesting of major grain crops, and the harvesting progress of soybeans was slightly later than that of corn and rice. It is demonstrated that the self−developed CGG and HM models can effectively evaluate the growth and harvesting status of major grain crops in the major grain−producing areas of Heilongjiang province, and the crops showed a favorable growth trend with timely harvesting in the region from 2019 to 2023.

Key words: Heilongjiang province, Major grain crops, Crop growth, Harvest progress