Eyad Alkhaled*(1) and Rada Kassouha(1)
(1). General Organization of Remote Sensing (GORS), Damascus, Syria.
(*Corresponding author: Dr. Eyad Al Khaled. E-Mail: eyadalkhaled@gmail.com).
Received: 27/07/ 2015 Accepted: 07/09/ 2015
Abstract
Drought is a natural phenomenon that decreases plants biomass, which can be monitored using Normalized Difference Vegetation Index (NDVI). The study aimed to monitor the periodical and spatial changes of plant cover, and drought in Agriculture Stability Zones (ASZ) in Syria, using NDVI/MODIS images, and link them with the rainfall data during 2001- 2012. The results showed that the lowest NDVI values were recorded for zones 1 to 5; the averages during 2008 were 0.412, 0.259, 0.172, 0.131, and 0.109 respectively. The year 2008 was considered the most drought year during the studied period. On the other hand, the year 2003 was considered the least drought year during the same period. The averages of NDVI of the five zones were 0.55, 0.49, 0.37, 0.28, and 0.18 respectively. Al thought there was a high significant correlation (r=0.89*) between rainfall and NDVI during the studied period. The output maps of MODIS using NDVI for the studied period, which is classified to 13 classes, showed that the largest area was for zone 1 of the classes 7, 8, 9, and 10, and the NDVI values ranged from 0.3 to 0.7 which representing rain fed and irrigated crops, and a specific percentage of the horticulture. Zone2 was included in the classes 6,7, and 8 for the NDVI values that ranged from 0.2 to 0.5, which representing grass and rain fed crops, but zones 3 and 4 were included in the classes 5,6, and 7 for the NDVI values that ranged from 0.1 to 0.4, which representing low cover with grass and rain fed crops, finally Zone 5 was included in two classes; 4, and 5 which were dominant and representing low and semi grass cover, with an area about 91.3% of zone 5.
Key words: NDVI, Agricultural stability zones, Biomass, MODIS, Syria.
Full paper in Arabic: