This chapter starts with a brief overview of the agro-climatic and agronomic conditions in China over the reporting period (section 4.1). Next it describes the situation by region, focusing on the seven most productive agro-ecological regions of the east and south: Northeast China, Inner Mongolia, Huanghuaihai, Loess region, Lower Yangtze, Southwest China, and Southern China (4.2). Section 4.3 describes trade prospects (import/export) of major crops. Additional information on the agroclimatic indicators for agriculturally important Chinese provinces are listed in table A.11 in Annex A.

4.1 Overview

Agro-climatic conditions were below average in China from October 2020 to January 2021, with rainfall, temperature and radiation deficits by 24%, 0.4°C and 3%, respectively, which resulted in a below-average potential biomass (-11%). Due to the complexity and variability of climatic conditions in China, weather conditions vary over different agroecological zones. Temperatures in six of the agroecological zones (AEZs) of China were below average, ranging from -1.5°C to -0.1°C. Only Northeast China had above-average temperatures. All AEZs except for Northeast China suffered from water shortage, and the departure of rainfall from the 15YA ranged from -44% to -3%. Drier conditions may potentially hamper the sowing and early growth of crops after winter. Since potential biomass is a synthetic indicator taking rainfall, radiation, and temperature into consideration, potential biomass in all seven AEZs was below average, with the biggest negative departure of -20% in Southwest China and the smallest negative departure of -4% in Southern China, indicating the unfavorable agroclimatic conditions.

Rainfall departure clustering and temperature departure clustering reveal detailed spatiotemporal patterns. Rainfall in 60% of the agricultural area was generally near average, and mainly located in northern China, and some areas in southwestern parts of China. Other regions in China went through some small fluctuation in rainfall. Relatively excessive rainfall (more than +30mm/dekad) occurred mainly in early October predominantly in the provinces of Chongqing, Anhui, Hubei, and some parts in adjacent provinces. Rainfall deficit (more than -30mm/dekad) mainly happend in early November in the provinces of Guangxi, Guangdong, Fujian, Jiangsu, and Hunan. Interestingly, the variations of temperature of two clustered regions were quite similar (marked in light green and blue), with temperatures below the average for most of the time during the monitoring period.

Only 9 provinces had positive rainfall anomalies such as Henan (+17%), Heilongjiang (+15%), and Jilin (+10%). The positive temperature anomalies were only recorded in 3 provinces of Heilongjiang (+0.4°C ), Jiangsu (+0.3°C) and Zhejiang (+0.1°C). Winter wheat cultivated across northern China is going through the hibernation period, while there were hardly any crops grown in Northeast China and Inner Mongolia during this period. CropWatch will keep monitoring the agro-climatic and agronomic conditions in the following bulletins.

Table 4.1. CropWatch agro-climatic and agronomic indicators for China, October 2020 to January 2021, departure from 5YA and 15YA

Figure 4.1. China crop calendar

Figure 4.2. China spatial distribution of rainfall profiles, October 2020 to January 2021

Figure 4.3. China spatial distribution of temperature profiles, October 2020 to January 2021

Figure 4.4. Cropped and uncropped arable land over winter crops producing provinces, by pixel, October 2020 to January 2021 

Figure 4.5. China maximum Vegetation Condition Index (VCIx), by pixel, October 2020 to January 2021

Figure 4.6. China Potential biomass departure from 15YA, by pixel, October 2020 to January 2021

4.2 Regional analysis

Figures 4.7 through 4.13 present crop condition information for each of China’s seven agricultural regions. The provided information is as follows: (a) Phenology of major crops; (b) Crop condition development graph based on NDVI, comparing the current season up to October 2019 to the previous season, to the five-year average (5YA), and to the five-year maximum; (c) Spatial NDVI patterns for October 2020 - January 2021 (compared to the (5YA)); (d) NDVI profiles associated with the spatial patterns under (c); (e) maximum VCI (over arable land mask); and (f) biomass for October 2020 - January 2021. Additional information about agro-climatic indicators and BIOMSS for China is provided in Annex A.