Download Solution sheet about the case studies Egypt and Spain

Food & Climate – More – Predicting the future - Worksheet 3 –
Solution sheet about the case studies Egypt and Spain
1. Irrigation systems
Agriculture in Egypt is restricted to the fertile lands of the Nile valley and the Nile delta. In these areas the agricultural
land has to be irrigated almost permanently. In most cases, flood water from the Nile river is simply sprayed onto the
fields and left to infiltrate the soil.
Crop irrigation is also very important in Spain. Here agricultural land is generally irrigated using the drip irrigation
method. Water is delivered directly to each plant, drip by drip, through special nozzles.
Search the internet for pictures of drip-irrigation. Compare these two sorts of irrigation and carefully
consider the pros and cons of each method. Which technique suits each country the best?
Pros
1. spraying the water directly
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Simple
Low running costs
Special knowledge is not needed
Machines can be used easily
Cons
1. spraying the water directly
 Erosion
 Very low efficiency
 Big water losses (evaporation,
water trickles away, surplus water)
 Generally no drainage 
oversalted fields
 Uneven water distribution (only
used in times of floods)
2. drip-irrigation
2. drip-irrigation
 Very low evaporation
 High efficiency
 Can be adapted to the water needs
of different plants
 Possible distribution of fertilizer
and pesticides while irrigating
 A very economical way of
irrigation
 Drainage is not needed
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The nozzles are easily blocked up
The technique is very expensive
Machines can hardly be used
Qualified workers with lots of
knowledge are needed
Both irrigation methods have pros and cons. The simple spraying technique used most commonly
in Egypt is simple and requires little training and no expensive equipment. It is not, however, a very
efficient method. It uses a lot of water, much of which simply evaporates back into the air. Flood
water is used as the water source so the effectiveness of the method depends on how often the river
floods. Drip irrigation is a much more efficient way of using precious water resources. The water is
delivered directly to the plants and little is lost through evaporation. The water can be stored in
reservoirs and tanks and used when it is needed. The method is, however, expensive and highly
trained people are needed to operate it.
Source of the pictures: http://satgeo.zum.de/satgeo/beispiele/interpretation/klipicts.htm
2. Climate change scenarios in Spain
a) Have a look in your atlas. Make a list of the main agricultural areas in Spain and what crops are
grown in each area.
Product
Regions
Wheat
Mainly around Valladolid, west of Madrid, east of Sevilla, north and west of Albacete, along
the river Ebro from Victoria to Zaragoza, south and along the river Guadalquivir from Sevilla
to Linares, around Badajoz
Corn
Along the Atlantic coast in the North
Rice
Only a small region south of Sevilla along the delta arms of the Guadalquivir
Sugar-beet
Around Valladolid, Lerida and Zaragoza
Cotton
Also along the Guadalquivir from Linares to Sevilla
Olives
Mainly south of the Guadalquivir and near the Mediterranean coastline, partly also along
the Ebro and the Guadiana
Fruit and vegetables
Mainly also along the Mediterranean coastline
Sunflowers
East of Madrid in the centre, south of the Guadalqqivir, around Badajoz
Vines
Along the Ebro, around Barcelona, south of the Guadiana in central Spain, along the
Mediterranean coastline in the South, around Alacete
(List was drawn up using data from the DIERCKE Weltatlas, Westermann Germany 1996. Page 100/101.)
b) Briefly describe and compare the four scenario maps of Spain. What are the conditions like for
agriculture in Spain today? What is likely to happen in the future?
GG = scenario considers the effects of greenhouse gases alone. GS = scenario considers the effects of greenhouse
gases and sulphate aerosols. Sulphate aerosols reflect sunlight back into space and this effect helps cool our planet.
Despite the uncertainties associated with the use of Global Climate Models, it is clear that, even in the best case
scenario (GS) agricultural production is likely to decline in the Central and Southern regions of Spain. These are
currently the most productive regions of the country. Considering the current high production costs and the variability
in the amounts of water available for irrigation, crop growth may have to be abandoned in some areas, unless major
changes in crop management are implemented.
Irrigation only helps in some areas to achieve a positive yield change e.g. in central Spain either in GG and GS
scenarios or in the Northeast under GS scenario. In regions with more precipitation in summer (the regions in the
North and Northwest) irrigation is not needed to get positive changes in yields.
These scenarios show that the greatest negative effects of climate change will happen in the areas which are
currently the main agricultural production areas in Spain. One possible consequence could be that agriculture in
these regions will be abandoned and other industries such as tourism will take over. If agricultural production doesn’t
move to the wetter northern regions, Spain will loose an important export. Other sectors will have to fill the gap in the
economy. Another possibility is to change the types of crops grown to those that are better able to cope with dry
conditions.
Lowering CO2 emissions now would decrease the negative effects of climate change predicted for the future.