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Sri LankaMain producing and exporting countries

Authors: 超级管理员 | Edit: zhuliang

This report covers both the main Maha and the second Yala cropping seasons of Sri Lanka. The Yala season crops were harvested in August and September. The sowing of main season crops (maize and wheat) started in October. Sri Lanka had abruptly switched to organic farming in 2021 and banned the import of chemical fertilizers. The ensuing lack of nutrients for the crops has reduced productivity. According to the CropWatch monitoring results, crop conditions were assessed as slightly below average for the monitoring period.

During this period, the country mainly experienced the Southwest-Monsoon Season, which is accompanied by windy weather and rains. However, at the national level, precipitation was markedly below the 15YA (RAIN -13%), while temperature and radiation were slightly below the average (TEMP -0.1°C, RADPAR -1%) . The fraction of cropped arable land (CALF) increased by 1% and BIOMSS was up by 1% compared to the 15YA. As shown in the NDVI development graph, NDVI was average during most of the period. The maximum VCI for the whole country was 0.92.

As shown by the NDVI clustering map and profiles, near half of country's cropland showed average and above-average crop conditions during August and September. These croplands were mainly located in the east, but there were also some clustered areas throughout the country. The abnormal NDVI departure values in early September and early October were mainly caused by cloud cover in the satellite images. The maximum VCI showed high values almost all over the country except for east coast.

Regional analysis

Based on the cropping system, climatic zones and topographic conditions, three sub-national agroecological regions can be distinguished for Sri Lanka. They are the Dry zone, the Wet zone, and the Intermediate zone.

In the Dry zone, the recorded RAIN (556 mm) was 8% below average. TEMP was 0.2°C above average and RADPAR was average. BIOMSS increased by 5% as compared to the 15YA. CALF was up by 1% as compared to the 5YA level with 98% of cropland utilized. NDVI was similar to that of the whole country. The VCIx for the zone was 0.93. Overall, crop conditions were near average for this zone.

For the Wet zone, RAIN (1855 mm) was 16% below average as compared to the 15YA. TEMP and RADPAR decreased by 0.5°C and 3% respectively. BIOMSS was 4% below the 15YA and cropland was fully utilized. NDVI values showed negative deviation from average. The VCIx value for the zone was 0.97. Crop conditions were below average for this zone.

The Intermediate zone also experienced sufficient rain (945 mm) but with an 18% decrease from the 15YA. TEMP was 0.3°C above average and RADPAR was average compared to the 15YA. With full use of cropland, BIOMSS was comparable to the average. The NDVI values were similar to the whole country and the VCIx value for this zone was 0.96. Conditions of the crops were below average.

 

Figure 3.27. Sri Lanka crop condition, July– October 2022

 

(a) Phenology of major crops

 

(b) Crop condition development graph based on NDVI

 

(c) Rainfall profile

 

(d) Temperature profile

 

(e) Maximum VCI

 

(f) Spatial NDVI patterns compared to 5YA  (g) NDVI profiles

 

(h) Crop condition development graph based on NDVI(Dry zone (left) and Wet zone (right))

 

(i) Crop condition development graph based on NDVI (Intermediate zone)

 

Table 3.45. Sri Lanka agroclimatic indicators by sub-national regions, current season's values and departure from 15YA, July– October 2022

Region

RAIN

TEMP

PADPAR

BIOMASS

current (mm)

Departure from 15YA (%)

current (°C)

Departure from 15YA (°C)

current (MJ/m2)

Departure from 15YA (%)

current (gDM/m2)

Departure from 15YA (%)

Dry zone

556

-8

27.4

0.2

1260

0

1175

5

Wet zone

1855

-16

23.6

-0.5

1130

-3

1490

-4

Intermediate zone

945

-18

24.9

0.3

1159

0

1236

-1

 

Table 3.46. Sri Lanka agronomic indicators by sub-national regions, current season's values and departure from 5YA, July– October 2022

Region

CALF

Maximum VCI

Current (%)

Departure from 5YA (%)

Current

Dry zone

98

1

0.93

Wet zone

100

0

0.97

Intermediate zone

100

0

0.96