Despite the fact that Google Scholar has algorithms that can help suggest interesting papers, this did not come under my radar until today, about a year after publication. It is a freely available special issue focusing on topics related to water, food security and energy in the Middle East, which is right up this blog’s alley!
I found it as I was reading an article about virtual water in the Middle East, which was part of this special issue without me realizing it. The title of that article was: Food-water security and virtual water trade in the Middle East and North Africa and it’s an interesting article that shows how much virtual water the Middle East actually imports through food. For example we learn that the MENA is the largest virtual water importer after the European Union and has been (at least) since 1986. In 2010 it imported about 800 cubic meters per person and year. Another interesting fact I found out was that between 1986 and 2010, Turkey was the largest exporter of virtual green water (i.e. water in rainfed crops), while Egypt, Turkey, Iran and Syria were the largest exporters of virtual blue water (i.e. water in irrigated crops) in the MENA region. At the same time Turkey were one of the largest importers of blue virtual water, together with Saudi Arabia, while Egypt were the major green water importer. If nothing else this shows the complexity of the Middle Eastern food security system, which is important to be aware of when studying agriculture and land use from a remote sensing perspective.
Did you know that during the period that the data is taken from the MENA region imported most of its green water from USA, Argentina, Australia and Brazil, and most of its blue water came from USA, Pakistan, France and India? Interesting to note is that Pakistan is (was) a net exporter of virtual water (mainly blue water), but also suffering an internal water deficit. How does that work out?
Another interesting article that I found was named Impact of the Syrian conflict on irrigated agriculture in the Orontes Basin, and seemed similar to what I’ve been working on in Kurdistan. It investigated, using remote sensing of satellite images, how conflict may have impacted agriculture by looking at a set of study areas in Syria and Lebanon with and without conflict. It suggests a drop of between 15 and 30% in agricultural production in the conflict areas, but to me it’s not 100% clear how they have reached that conclusion.
They used summer time NDVI (from Landsat) to determine Fraction of Vegetation Cover (FOV) and compared the FOV of 2013 to the mean FOV of 2000-2011, basically looking at the anomalies for that particular year. According to the authors this is an indication of a reduction in irrigated area, or/and an indication of crop water stress. The questions these results leave me with (maybe I’ve missed something in the article) are, however:
- Was any land use data used to identify cropland?
- What about areas with winter crops that are harvested before the summer months?
- What about pastures/grasslands?
- What about fallow practices?
In my opinion, cropland activity is better identified using seasonal vegetation patterns, where a noticeable decrease in NDVI or EVI marks a harvest, indicating that someone is farming the land.
To conclude, I like the idea of the paper, but I think the methodology could be much more solid, connecting the indices more strongly to what is happening on the ground. After all, human-environment systems are much more complex than we like to think when modelling them.