When Fresh Water becomes Salt Water
The article was based on an interview with Wim Van Isacker from the Flemish Land Agency, a partner in SalFar, who explained that drought does not only constitute a problem in terms of making it difficult for plants to grow as there is not enough water. It also means a problem for the ground becoming salinized, which can seriously damage the fertile soils.
In polder areas, it is normal that there is saline groundwater. The saline groundwater naturally salinizes the surface water in the ditches, but that saline water is under normal conditions diluted with fresh water and in the end transported to the sea.
In long periods of drought this “flushing” process does not happen and the surface water thereby gradually becomes more saline until in the end it is not suitable anymore for animals to drink, as well as for the irrigation of crops. This can lead to a permanent damage of fertile soils.
Storing more fresh water could be one solution to mitigate the challenge of dry periods, Wim explains, e.g. by storing water in ponds and enabling subsurface storage in creek-ridges.
However, we cannot be sure of whether there will be enough water to store and if we will be able to store sufficient quantities. Wim’s message to the farmers was therefore that other mitigation measures also need to be taken into account, namely adaption of agricultural methods, like saline farming, which is what we are doing in the SalFar project.
The option is to grow more salt tolerant crops such as special varieties of potatoes, carrots, beetroots or cabbage on farmland in danger of salinization or farmland that has already been salinized. Apart from having a higher salt tolerance than conventional crops, these varieties are also more resistant to drought and could offer an alternative to traditional fresh water farming.