I was asked by Michael Victor to post my reply on Linkedin here so you could see my comments.
Interesting article, but it let me with lots of questions. First irrigated crops are annuals that are planted every year, which also means more plowing, tilling, soil manipulation, fertilization, etc. Since cultural practices and uses for licorice are totally different than grain crops or fiber crops, how are you comparing the total difference just due to licorice. You would also have to incorporate another perennial crop that would be in the ground for the same amount of time in order to see if the exudates from the licorice root are the difference or if taking the soil out of annual production for three to four years is the factor.
If licorice is native to the area, then the difference could also be due to soil microbes that have built symbiotic relationships with this native plant. I am suspicious that the grain and fiber crops presently grown are not native.
The reference to the crops being brought in during Soviet occupation also makes me wonder. The Soviets were known to exploit the resources of the non-Russian countries and use them up while preserving Russian resources. To continue use of the land in the same way is still exploitive and it sounds like no efforts to restore fertility and sustainability of the soil has been addressed until now. I know that many soils in Uzbekistan are considered marginal too, so the present methods could be turning land that traditionally was used for pasture into desert. There is usually not one magic bullet that will restore soils to their original state. Restoring the water table, restricting fertility to the level the soil can actually handle, getting more organic matter back into the soil (if possible), etc. are all needed. One plant that has shown promise by the stream banks, and incidentally not grown in the middle of the production area, seems to me to be a reach. Also, do the farmers use the same level of other chemicals like herbicides, pesticides, fungicides (which also are usually in a salt form) on licorice? My guess is probably not. The research must be absolutely correct in its design to get the answer you want.
I was asked by Michael Victor to post my reply on Linkedin here so you could see my comments.
Interesting article, but it let me with lots of questions. First irrigated crops are annuals that are planted every year, which also means more plowing, tilling, soil manipulation, fertilization, etc. Since cultural practices and uses for licorice are totally different than grain crops or fiber crops, how are you comparing the total difference just due to licorice. You would also have to incorporate another perennial crop that would be in the ground for the same amount of time in order to see if the exudates from the licorice root are the difference or if taking the soil out of annual production for three to four years is the factor.
If licorice is native to the area, then the difference could also be due to soil microbes that have built symbiotic relationships with this native plant. I am suspicious that the grain and fiber crops presently grown are not native.
The reference to the crops being brought in during Soviet occupation also makes me wonder. The Soviets were known to exploit the resources of the non-Russian countries and use them up while preserving Russian resources. To continue use of the land in the same way is still exploitive and it sounds like no efforts to restore fertility and sustainability of the soil has been addressed until now. I know that many soils in Uzbekistan are considered marginal too, so the present methods could be turning land that traditionally was used for pasture into desert. There is usually not one magic bullet that will restore soils to their original state. Restoring the water table, restricting fertility to the level the soil can actually handle, getting more organic matter back into the soil (if possible), etc. are all needed. One plant that has shown promise by the stream banks, and incidentally not grown in the middle of the production area, seems to me to be a reach. Also, do the farmers use the same level of other chemicals like herbicides, pesticides, fungicides (which also are usually in a salt form) on licorice? My guess is probably not. The research must be absolutely correct in its design to get the answer you want.