This reporting period covers the main harvesting stage of medium rice, late rice and floating rice, which had a slightly below average production estimate according to the previous monitoring period. The period also covers the main growth stage of dry season early rice, dry season maize, and soybean, which benefitted from  favorable growth conditions as monitored by the Cropwatch system.

During this monitoring period, Cambodia experienced wetter and relatively cooler weather conditions. Compared to the same period of the past 15 years, the precipitation in Cambodia was 27% higher (RAIN), while the average temperature was slightly cooler by 0.1°C (TEMP) and the radiation was slightly higher as well (RADPAR +1%). The abundant rainfall resulted in a 14% higher potential biomass  (BIOMSS) than average, which shows a favorable climatic condition for crop growth, which is consistent with the NDVI profile. As is shown by the NDVI profile, the national-scale NDVI recovered to average in mid-January, then reached and exceeded the maximum value of the past 5 years in February and March. Since mid-January, NDVI has stayed above average. According to the spatial NDVI patterns, 4 patterns could be identified: 1) about 59.3% of the cropland (in red and light green) in the country experienced a positive NDVI deviation, and these croplands were mainly located in the lower Mekong River basin and around the Tonle Sap Lake. 2) about 21.7% of the cropland (in dark green) maintained a slightly below-average NDVI, and these croplands mainly appeared in the northwestern Banteay Meanchey and were scattered in the lower Mekong River basin. 3) around 12.8% of the croplands (in blue) experienced a steady decline from the peak starting in mid-February. These croplands were mainly located in southern Banteay Meanchey and western Prey Veng. 4) the remaining 6.2% of the croplands (in yellow) had a below-average NDVI throughout the entire period. These croplands were in southeastern Kandal and western Prey Veng. Considering that the VCIx value was as high as 0.93 and the CALF index significantly rose by 12%, both the growth of soybean and the estimated production of dry-season maize and dry-season early rice were favorable.

Regional analysis

Based on cropping systems, climatic zones, and topographic conditions, four sub-national regions are described below: The Tonle Sap Lake region, a seasonally inundated freshwater lake which is influenced by the inflow and outflow from the Mekong River, the Mekong valley between Tonle Sap and Vietnam border, Northern plain and northeast, and the Southwest Hilly region along the Gulf of Thailand coast.

For Tonle Sap Lake region, it experienced a 34% higher precipitation (RAIN), 0.3°C lower temperature (TEMP), and about 1% higher radiation (RADPAR), resulting in a 15% higher potential biomass (BIOMSS). The regional NDVI was close to average in January and then remained above average. Noteworthily, the NDVI exceeded the maximum value of the past 5 years in March. In addition, the CALF index in this region increased by 18% and the VCIx value was as high as 0.92, indicating favorable crop conditions.

For the Mekong Valley region, the precipitation in this zone was significantly higher by 38% (RAIN), the temperature was near average (TEMP), and radiation was 1% higher (RADPAR). Abundant precipitation resulted in a higher potential biomass (BIOMSS +15%), indicating favorable climatic condition for crop growth. Like the Tonle Sap Lake zone, the NDVI in this zone was close to average in January and then gradually approached the maximum level of the past 5 year in March. Considering that the regional CALF index increased by 9% and the VCIx value reached 0.93, the crop condition in this zone is predicted to be favorable as well.

For the Northern plains and Northwest, the zone had an 8% higher precipitation (RAIN), about 0.1°C higher temperature (TEMP), and average radiation (RADPAR), resulting in a potential biomass increase by about 8% (BIOMSS). Crop NDVI in the zone was close to average before early February, and then increased and was higher than average. The CALF index in the zone reached 98% and the VCIx value was at 0.93, so the crop production in the zone is estimated to be favorable as well.

For the Southwestern hilly region, precipitation in this region was 43% above average (RAIN), temperature was about 0.6°C lower (TEMP), and radiation was about 3% higher (RADPAR), resulting in a higher potential biomass in this region (BIOMSS +21%). In terms of the NDVI profile, the NDVI was likewise close to average in January and then gradually rose and was close to the maximum level of past 5 years. Meanwhile, the CALF index was as high as 99% and the VCIx index was close to 0.93, so the crop condition in this region was favorable as well.

Figure 3.26 Cambodia's crop condition, January - April 2022

(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) Time series temperature profile (left) and rainfall profile (right)

(g) Crop condition development graph based on NDVI (left) and time series rainfall profile (right) in Tonle Sap Lake area

(h) Crop condition development graph based on NDVI (left) and time series rainfall profile (right) in Mekong valley region

(i) Crop condition development graph based on NDVI (left) and time series rainfall profile (right) in Northern plain and northeast zone

(j) Crop condition development graph based on NDVI (left) and time series rainfall profile (right) in Southwest hilly region

Table 3.41 Cambodia's agro-climatic indicators by sub-national regions, current season's values, and departure from 15YA, January - April 2022

Table 3.42 Cambodia's agronomic indicators by sub-national regions, current season's values, and departure from 5YA, January – April 2022