1. Crop Classification Methods

Global agricultural monitoring comprehensively considers regional differences in agroecology, cropping patterns, farm management practices, and ground-based data. A monitoring system was established with agroecological zones as the basic unit, adopting a microservices architecture. Various technologies have been encapsulated into APIs, including soybean index, maize index, rapeseed index, random forest classification, sample-free and small-sample crop classification, spatiotemporal transfer classification, and a two-step method for rice potential area identification and fine-scale extraction. By integrating semantic segmentation and artificial intelligence models, the system enables rapid cleaning of survey data and precise crop type identification. The use of massive crowdsourced data, combined with multiple classification models and techniques, supports crop mapping in major cereal and oilseed producing and exporting countries. In addition, non-cropland coefficients are quantified based on high-resolution field extraction results and cropland distribution data, and combined with crop mapping results to achieve high-precision monitoring of cultivated areas.

2. Crop Yield Prediction Methods

CropWatch has developed an interactive crop yield prediction system by coupling spatial distribution of crops, phenological information, and a "biomass-harvest index" model, enabling effective crop yield monitoring.

3. CropWatch Indicators

CropWatch indicators are used to assess agricultural environments as well as crop growth conditions and dynamics. Three types of indicators are primarily employed to analyze crop performance across different spatial units:

(i) Agro-environmental indicators, which reflect the potential impacts of weather factors such as rainfall (RAIN), temperature (TEMP), and photosynthetically active radiation (PAR) on crop growth, as represented by Biomass accumulation potential (BIOMSS);

(ii) Remote sensing-based agroclimatic indicators, which describe the current growth conditions of crops, including the Vegetation Health Index (VHI), the Cropped arable  land and cropped arable land fraction (CALF), and Maximum   vegetation condition index (VCIx);

(iii) Early warning indicators, which quantify the status of agricultural production, such as the Crop Production Index (CroPI), the Agricultural Drought Area Change Index (ADAC), and the Palmer Drought Severity Index (PDSI).

For more details, refer to: http://cloud.cropwatch.com.cn/web/method

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