Saline Agriculture - FAQ
Are there many differences between conventional agriculture and saline agriculture?
All aspects of growing crops such as choice of crop and variety, land preparation, fertilizer choice and use etc. need special attention in saline agriculture. However, in essence saline agriculture is very similar to conventional agriculture.
Since when is salinization a problem?
Salinization is as old as agriculture itself. Human induced salinization is often the result of irrigating with water that contains dissolved salts (all the water in the world contains at least some dissolved salts in it). When evapotranspiration is high, the salts stay behind in the soil and accumulate over time. So, if irrigation is insufficient to flush out the salts from the root zone, salinization is only a matter of time in areas where evapotranspiration rates are high.
In which parts of the world is salinization a problem?
Salinization is a problem on all continents (not on the south pole). Salinity problems are worst in arid and semi-arid parts of the world. Large parts of the middle east and northern Africa are affected by salinity problems and also in Australia yields are being reduced because of salinity problems.
How can we prevent salinization?
Salinization can be prevented by irrigating in a smart way and at the same time making sure there is appropriate drainage.
Do you think that The Netherlands is a suitable country for saline agriculture?
The Netherlands is one of the leading countries worldwide in terms of developments in agriculture. Additionally, a large percentage of the countries surface area lies below sea level which brings with it a constant threat of the intrusion of saline seepage water. Combining these two facts it makes sense to study the possibilities of saline agriculture in the Netherlands.
Is the production of fish or shellfish also part of saline agriculture?
Saline agriculture is part of agriculture. The production of fish, shellfish and seaweeds for example is part of aquaculture.
Are weeds less of a problem in saline agriculture?
Unfortunately, also in saline agriculture you can have weeds and one needs to control them. They are different species and the species richness is smaller, but there are always unwanted plants growing between your crops.
Do you use the same seeds or seed potatoes for saline agriculture or are there seeds or seed potatoes especially for saline agriculture?
As yet, no seeds or seed potatoes especially produced for saline agriculture are being produced. However, when you know which varieties or cultivars perform best under saline conditions, you can purchase those varieties that will produce the highest yields under saline conditions.
Because of the sensitivity to salt water on the leaves of most crops, does this mean you can’t spray irrigation water but instead you need to irrigate directly on the ground?
Yes, drip irrigation is the preferred form of irrigation in saline agriculture.
How come do plants not die when the salts enter the plants via the roots, but will die when the salt water is sprayed on the plants?
Indeed this is the case for most plants but there are exceptions. Of course, the level of salinity matters for this question, but in general it is true that plants are very sensitive for salt water on their leaves. This is because, when the water evaporates, the salts stay behind and, and at some point pure salt is left on the leaves which will burn them. However, as mentioned, there are exceptions to this. Sea kale (Crambe maritima) for example is very tolerant to salt water on its leaves but much less tolerant to high salinity levels in the root zone.
Are there different forms of saline agriculture? Saline agriculture on the sea and saline agriculture on land for example?
Producing food in the sea is part of aquaculture, whether you produce animals (fish, shellfish) or plants (algae). Personally I think there is a difference between doing agriculture on saline land or using brackish water for irrigation on non-saline land, but to my knowledge there are no different terms for those two forms of saline agriculture.
Is saline agriculture more labour intensive, or more expensive, than conventional agriculture?
There are certain conditions that are required for saline agriculture which, if not in place yet, may require an initial investment. Drainage for example is very important in saline agriculture, and irrigation is preferably done via drip irrigation. Fertilising your crops may require some extra effort and it is possible that seeds of salt tolerant varieties are a bit more expensive than seeds of more common or conventional varieties. However, when all the requirements are met it is not necessarily a more expensive form of agriculture.
Is the process of sowing and harvesting the same in saline agriculture?
Yes, sowing seeds and the harvest of your products is the same in saline agriculture.
What is the purpose of developing salt water irrigation methods?
If we can use brackish water for irrigation, then we can double the amount of water that is available for agriculture. Saline irrigation is tricky and not possible in all locations, but we are looking into all possibilities. Furthermore, fresh water irrigation on salt affected soils can contribute to food security in many areas.
What is the difference between the produce that you grow & freshwater produce?
For potato we know that the taste improves when cultivated under saline conditions, for carrot the dry matter content and sugar content increase. So these are all positive differences.
What kinds of vegetables do you currently grow? What vegetables are you working on to grow / do you think you will be able to grow in salt water based on your experience?
Potato, cabbage, cauliflower, carrot, tomato, fodder, legumes, lettuce, other brassica species are our main focus now. We are finding salt tolerant varieties of these crops all the time.
Which parts of the world would benefit from the most from saline agriculture?
Parts of the world that have a (semi-) arid climate, irrigated crops or salt affected soils.
What is the nutritional profile of produces cultivated through saline agriculture? Does the salt content increase? Is it not unhealthy?
The effect of salinity on the nutritional content of crops has been generally positive, increases in antioxidants and minerals have been observed.
Scientific explanation: The effect of salinity on the nutritional value and salt content depend on the crop species. Really salt tolerant plants known as halophytes accumulate the salts in the leaves and for this reason, will contain a lot of salts. However, most crops will avoid excessive accumulation of salts in their tissues and the rise in internal salt concentration is relatively modest (this is especially true for crops in the family of the Gramineae).
Additionally, crops may preferentially store salts in certain organs and not in others which may be the parts we eat. For example, the accumulation of salts in a potato grown under saline conditions is a lot lower than the amount of salt most people add to the potato when eating it.