October to January covers the growing period of the main (wet season) rice crop, and the early stage of the second (dry season) rice in Cambodia. Crop condition is globally average. The fraction of cropped arable land was a slightly above the average of the previous five years (+1%). Compared to average, the CropWatch agro-climatic indicators show a sharp decrease in radiation (RADPAR, -8%) but nevertheless average temperature. Rainfall increased significantly (RAIN, +39%), causing a 34% increase in the biomass production potential (BIOMSS). 

Favorable water supply conditions resulted in above average crops throughout the season. Abundant rainfall was beneficial for the sowing and emergence of the second rice crop. Vegetation condition indices (VCIx) are high (>0.8) in most parts of the country. Crop condition is favorable in the whole country, most areas enjoy above average NDVI which exceeded average by as much as 0.2 at the end of 2017 in some locations near Phnom Penh. Only about 4% of croplands suffers below average crop condition, but recovered before January.  Altogether, the condition of crops in the country is better than average.

Based mostly on climate differences, two agro-ecological regions can be distinguished in Cambodia. Weather in the Tonle Sap lake area (especially rainfall and temperature) is mainly influenced by the lake itself. The second area, referred to as the "main crop area" covers  areas outside the Tonle Sap basin along the border with Thailand and Laos in the north and Vietnam in the east.

For the current reporting period, the two major crop area share similar agro-climate conditions and similar crop condition can thus be expected. Under average NDVI recovered before February because of sufficient water supplying. Unusually low NDVI is partly due to cloud contamination. 

                                         Figure 3.19. Cambodia crop condition, October 2017-January 2018

                                                  (a). Phenology of major crops

(b) Crop condition development graph based on NDVI                             (c) Maximum VCI

(d) Spatial NDVI patterns compared to 5YA               (e) NDVI profile

(f) Crop condition development graph based on NDVI (Lake area of Tongle Sap (left) and Main cropping area (right))

Cambodia agroclimatic indicators by agro-ecological region, current season's values and departure from average, October to January 2018