Home: TRD: Resource utilisation: AGRI-OUTLOOK: NDVI FOR May 2008
Two approaches are used i.e. NDVI (plant activity) and PASG (accumulated seasonal greenness). It is expected that above normal rains of the current season should result in above normal conditions for plant activity. In general, all three images indicate at least similar to above normal plant activity or greenness, compared to last year and the long term. Interestingly, more plant activity was recorded in the east, which was ascribable to the nature of plants being more summer rainfall oriented. The western side of the province obviously had less plant activity or greenness due to the remarkably less acreage of actively growing or developing crops this time of the year. The green spots could probably be matched with eg. vineyards, orchards, potatoes (Sandveld), summer crops under irrigation, ect.
The current drought experienced in the mid Central Karoo is clearly pointed out in all three images. The fact remains that the drought is certainly abnormal, thus emphasising the appropriate aid to those producers in the affected area.
Other below normal situations (red) can also be seen, although being much smaller areas and isolated. These will be verified and if necessary carefully monitored and during the following months.
20 – 31 May 2009
NDVI values were low over the Karoo while the highest values occurred over the mountainous areas reflecting the actual vegetation activity.
21-31 May compared compared to 21-31 May 2008
The NDVI was higher over the interior than during May 2008 but somewhat lower over the southern and northwestern parts.
21 – 28 May 2008 compared with the long-term mean
The NDVI during May 2009 was lower than average over the southern parts of the province, but higher than average over large parts of the interior.
Percentage of Average Seasonal Greenness (PASG): April - May 2009 compared with the long-term mean
Percentage of Average Seasonal Greenness (PASG) for this period was normal to above normal over the western and northern parts of the province. However, the dry conditions in the south are having a negative impact on the cumulative vegetation activity over the area.
