الفهرس | Only 14 pages are availabe for public view |
Abstract Water scarcity is a problem facing countries at the present time, and it is difficult to provide large quantities of water that are sufficient to produce crops that are imported from abroad. For calculating the virtual amount of water for crops, the amount of water needed by the crop during its cultivation period was calculated by knowing its productivity and then calculating crop water requirement. With entering of weather, crop and soil factors by using a program of CropWat with neglecting the effect of rain and knowing the crop constant for the required crops, specific water demand is obtained. Determining the amount of exports and imports of crops using the statistics of the Food and Agriculture Organization, and then the exports and imports of crops (tons) were converted to virtual water, by taking the value of the export or import (in tons) multiplied by the crop’s water needs (cubic meters per ton). The consumption of crops and the global price per ton are determined so that the crops that consume the highest water and the lowest price are determined and imported and the crops that consume the least water and the highest price are produced and exported. Different scenarios have been worked out to determine what is imported and what is exported from the crops that achieve the economic aspect, which is the aim of the study (the conversion of water quantities into money). For example, to know the costs of the amount of water needed by a particular crop to produce a ton of it, we take the price of the cubic meter of water multiplied by the required quantity and compare it with the prices required to import it. After the current study, the quantity of exports and imports of the different crops over the years has been reached and converted to water (virtual water) and the plotting of curves that show over the years whether there is import or export of crops and work to predict whether there is a deficit in export or not in the future until a year 2050. The study contained the quantities of water needed to produce the crops that need water and as a result of their scarcity are imported from abroad taking into account the earliest years of monitoring these rates with the dependence of weather, soil and crop factors by using specialized programs. Thus, virtual water trade forms important factor to solve water scarcity. |