The monitoring period (January to April 2023) covers the early growth to flowering stages of winter wheat in Huanghuaihai. Agro-climatic indicators showed that precipitation (+21%) and temperature (+1.4°C) in this area were above the 15YA, but radiation was unchanged. As a result of these indicators, an increase in crop biomass production potential was estimated (BIOMSS +12%). The CALF exceeded the 5YA by 3%, indicating an increased cropping area. Below-average BIOMSS was located in northern Shandong.

According to the NDVI development graph, crop growth was below average due to the late spring cold. Sufficient rainfall and above-average temperatures caused an increase in NDVI, even above the average level since April. As the NDVI departure clustering map shows, 11% of the cropland exceeded the average before early April, mainly located in central Henan and northeastern Anhui. Crops in the areas of Shandong, northeastern Henan, northern Jiangsu, and the Bohai Bay area (yellow, red, and dark green colors in the NDVI departure clustering map) presented below-average conditions until mid-April but recovered quickly thereafter.

The maximum VCI value was 0.86, and the Crop Production Index (CPI) is 1.10. Generally, the crop conditions in this important winter wheat production region were normal.

(a) Crop condition development graph based on NDVI 

 (b) Spatial NDVI patterns compared to 5YA (c) NDVI profiles

(d)Time series rainfall profile

(e)Time series temperature profile

(f) Maximum VCI

(g) Biomass departure