CropWatch uses a national cultivated land data mask (10 m resolution), a remote sensing based index model, an agrometeorological yield estimation model and crop area estimation methods in order to estimate crop production in China. In addition, it makes use of thousands of  in-situ data points from more than 600 counties in Northeast China, North China and the middle and lower reaches of the Yangtze River that had been collected from July to October in 2020. They were used for the training and validation of machine learning algorithms to quantify crop damage, in addition to our standard processes to estimate the area and production of the main grain and oil crops  at the provincial level. 

We arrived at the following area and production estimates in China for the year 2020: We revised the total grain output in 2020 upward to 631.437 million tons, an increase of 5.06 million tons (+ 0.8%) over the same period last year. The total output of summer crops, i.e., corn, mid-season rice, late rice, spring wheat, soybeans, miscellaneous grains and tuber crops, is expected to be 466.489 million tons, an increase by 1.39 million tons (+0.3%) over 2019 (Table 4-2). The provinces with the highest year-on-year increase in summer crop grain and total annual grain output were mostly distributed in the Northwest, North China and the Loess Plateau, including Shanxi, Ningxia, Henan, Shaanxi, Shandong, Hebei and Gansu. The combined increase of all crops was more than 3% and the total grain output increased by more than 2% in these provinces. The provinces with the highest decline in autumn grain and total grain output included Jilin, Jiangxi, Jiangsu, Inner Mongolia and Heilongjiang. The reduction was mainly due to the typhoons which caused flooding and wind damage. 

Table 4.2 China 2020 winter crops, early rice, summer crops and total annual crop production (thousand tons) and percentage difference from 2019, by province

* Production of Taiwan province is not included.

The total national maize output in 2020 is 226.078 million tons, an increase of 1.73 million tons (+0.8%) from 2019. This was due to an increase in area and yield levels in the main producing provinces. The national maize planting area increased slightly by 0.2%, while the national average maize yield recovered from last year's lower yields and increased by 0.5% (Table 4-3). Benefitting from good rain and temperature conditions, maize production in the Huanghuaihai Plain, the Loess Plateau, and the Northwest Region increased significantly as compared to last year. Yield increases by more than 2% were estimated for: Henan, Hebei, Shandong, Shanxi, Shaanxi, Ningxia, Gansu and Xinjiang. Production estimates increased by more than 3.0% for Henan (+0.85 million tons), Shandong (+0.7 million tons) and Hebei (0.63 million tons), which are important maize producing provinces of China. 

Table 4.3 China 2020 production (thousand tons) of maize, rice, wheat, and soybean, and percentage change from 2019, by province

* Production of Taiwan province is not included.

Using a combination of remote sensing data from the whole growth period and meteorological data, the maize yields of four northeastern provinces were revised. The results showed that maize lodging caused drops by 0.950 and 1.18 million tons of maize production in Heilongjiang (-2.3%) and Jilin (-3.8%) provinces, respectively.  Inner Mongolia was affected by the lack of rainfall during the maize tasseling period, and the maize production decreased by 0.420 millon tons. The agro-meteorological conditions in Liaoning province were generally normal with sufficient rain and heat during the key growth period of maize, and the maize production increased by 0.650 million tons year-on-year. The total maize output of the four northeastern provinces decreased by 1.9 million tons year-on-year. On the other hand, the increase of maize yield in the Huanghuaihai plain, the Loess Plateau and the Northwest region more than compensated for the yield losses in the Northeastern provinces. Nationwide, maize production increased by 0.8%.

The total rice production of China was 201.176 million tons, with a decrease of 0.2% and a reduction of 440 thousand tons when compared to last year. The continuous heavy rainfall and floods in the rice-producing zones from June to August significantly affected the production of mid-season rice, which resulted in a decline of 0.740 million tons compared to 2019 and the total production was 132.452 million tons. Late rice benefitted from favorable agro-climatic conditions in the late growing season , the total production of late rice was 35.278 million tons, with an increase of 0.3% over  2019 (Table 4-4). Though the Northeast China suffered from three typhoons, the rice production was barely affected. A decrease by 0.050 million tons for the rice production was observed in Jilin Province, while Heilongjiang and Liaoning provinces both increased by 1%.

The total soybean production of China continued to increase following the trend of the past 5 years and reached 14.574 million tons this year, an increase of 0.130 million tons or 0.9%, when compared to 2019. At the national level, the cropping area of soybean increased by 0.5%. For the provinces of Shanxi, Inner Mongolia, Shandong, Liaoning and Hebei, the planted area of soybean increased by more than 1%. The agro-climatic conditions in North China were favorable, and soybean production increased by more than 4% in Hebei, Henan, Shanxi and Shandong provinces. The drought in July in Northeast China affected soybean during the pod setting season, which led to a decrease by 1.0%, 0.1% and 0.2% for soybean production in Heilongjiang, Inner Mongolia and Jilin respectively.

Table 4.4 China 2020 early rice, single rice/semi-late rice, and late rice production (thousand tons) and percentage difference from 2019, by province.

* Production of Taiwan province is not included.