According to the regional NDVI development graph, crop condition was generally fair in the Loess region. The main crops in the region are currently winter wheat, spring wheat, and spring Maize. Winter wheat was sowed during late September to middle October and will be harvested in middle June.Spring wheat and Maize were just sowed during late March to April. During the monitoring period, rainfall (RAIN) exceeded average by 38%, while temperature (TEMP) was 0.5°C above. Radiation (RADPAR) was 9% below average, which may adversely affect photosynthesis. NDVI clusters and profiles shows that crop condition was close to average in most parts of the region and even improved slightly in late April. The fraction of cropped arable land (CALF) for the region decreased 54 percentage points when compared with the five-year average, which indicates about half of the land is uncropped. The potential biomass indicator (BIOMASS) was 28% above average, with above average values in every province within the Loess region. According to the VCIx map, with the exception of central Shanxi and central Gansu, current crop condition in the region is quite favorable, especially in the north.

Figure 5.12. Crop condition China Loess region, January-April 2018

(a) Crop condition development graph based on NDVI

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

(d) Maximum VCI                                                (e) Biomass