The harvest of Thailand’s main rice was completely in early January, while the second season rice was ready for harvest in April, at the time when maize was being sowed. 

According to Agroclimatic indicators, rainfall was close to average over the reporting period (RAIN, +2%), while temperature (TEMP, -1.1°C) and radiation (RADPAR, -8%) were below. The biomass production potential (BIOMSS) is up by 9%, and the fraction of cropped arable land (CALF) also increased by 6% over its average for the period. Nationwide Crop condition based on NDVI was above average and reached the 5-year maximum before April. It slightly decrease later but remained above average. According to the NDVI departure clustering map, 25% of the arable land was below average over the monitoring period although it partially recovered from February (in the south and northeast of Thailand and in Nakhon Sawan). 20.6% of the crop areas were slightly better than 5-year average before March and decreased to slightly below average later (middle of Central double and triple-cropped rice lowlands and south of Western and southern hill areas). Other areas, accounting for 54.4% of cropland was below average before mid-January and recovered to above average in February. The areas under consideration include patches over the whole country except for Prachuap Khilikhan, Chumphon, Ranong, Phangnga, Krabi, Trang, Satun,Songkhla and Yala in south of te country. To sum up, crop condition is anticipated to be average or above but below last year's. For rice, Cropwatch projects that the production will decrease 5.2% compared to last years output.

Regional analysis

The regional analysis below focuses on some of the already mentioned agro-ecological zones of Thailand, of which some are mostly defined by the rice cultivation typology. Agro-ecological zones include Central double and triple-cropped rice lowlands (115), South-eastern horticulture area (116), Western and southern hill areas (117) and the Single-cropped rice north-eastern region (118). The numbers correspond to the labels in the VCIx and NDVI profile maps. 

Indicators for the Central double and triple-cropped rice lowlands follow the same patterns as those for the country as a whole: temperature (TEMP -1.1ºC) and radiation (RADPAR -10%) were below average, and accumulated rainfall was significantly above (RAIN +21%), resulting in a large biomass production potential increase in Thailand (BIOMSS +26%). According to the NDVI development graph, crop condition was above the 5-year maximum before April and reached to 5-year maximum in April. This is confirmed by a favorable VCIx index of 0.86. Overall, the situation was above average and may reach to maximum of previous 5 years.

The temperature of the South-eastern horticulture area suffered a decrease of 1.4ºC, while rainfall (RAIN, +54%) and radiation (RADPAR, -9%) experienced the same changes  as the whole country. The VCIx map, NDVI development graph, and BIOMSS indicators (the largest increase for all the AEZs, +45%) all lead to the conclusion that crop condition was close to 5-year maximum.

Crop condition in the Western and southern hill areas was average according to the  Agroclimatic indicators: TEMP -0.8°C, RADPAR -8%, and BIOMSS +1% when compared to their respective averages; rainfall (-6%) was below average. According to the NDVI development graph, crop condition was close to average. 

Finally, the situation in the Single-cropped rice north-eastern region was close to average. According to Cropwatch indicators rainfall (RAIN -5%), temperature (TEMP -0.5°C) and radiation (RADPAR -9%) were below average.  BIOMSS (+7%) shows above average values. The NDVI development graph shows that crop condition was close to average, which is confirmed by the NDVI profiles.

At the national level, most arable land was cropped during the season and had favorable VCIx values around 0.79. CropWatch projects that the production of rice will be below last year's output.

Figure 3.28a. Thailand phenology of major crops

Figure 3.28b. Thailand national level crop condition development graph based on NDVI, comparing the April-July 2017 period to the previous season and the five-year average (5YA) and maximum

Figure 3.28c. Thailand maximum VCI forApril-July 2017 by pixel

Figure 3.28d. Thailand spatial NDVIpatterns up to July 2017 according to local cropping patterns and compared tothe 5YA (left) and (e) associated NDVI profiles (right)

Figure 3.28f Central double and triple-cropped rice lowlands (Thailand) crop condition development graph based on NDVI

Figure 3.28g.Western and southern hill areas(Thailand)crop condition development graph based on NDVI

Figure 3.28h. South-eastern horticulture area(Thailand) crop condition development graph based on NDVI

Figure 3.28i. Single-cropped rice north-eastern region (Thailand) crop condition development graph based on NDVI

Table 70. January-April 2018agro-climatic indicators by agro-ecological region, current season values anddeparture from 15YA

Table 71. January-April 2018 agronomicindicators by by agro-ecological region, current season values and departurefrom 5YA

  Table 72. CropWatch estimated rice, wheatand soybean production for 2018 (thousands tons)

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