Population growth and economic
development have led in many countries with an arid or semi-arid climate to
scarcity of fresh water and arable land. Due to overuse and improper management,
ground water and soils become saline. Salt-tolerant plants (halophytes) enable
salt-affected ground water and land to be kept in use or to be put into use.
Freshwater resources can then be saved. Potential uses range from the production
of food and animal feed to use in landscape management and nature conservation.
The present study shows that halophytes are already in use all over the world and efforts to extend utilisation have been increased in recent years. However, information about economic feasibility is scarce and often based on single experiences. But the existing examples demonstrate that halophyte utilisation can be not only technically but also economically feasible. The economically motivated utilisation of halophytes emerges as an interdisciplinary task. Besides the natural conditions and properties of the species, economic and social constraints determine the technology and economic success. In particular, aspects of irrigation turn out to be crucial parameters. The control of soil salinity has top priority in saline irrigation. Wherever irrigation is necessary and where the use of halophytes has to compete with the use of common species, saline irrigation needs to be more cost-efficient than the conventional use of fresh water. Depending on the location, the potential to save costs can be immense. Halophytes can be of extraordinary value in times of drought and feed gaps. Landscaping with halophytes can reduce costs while providing benefits equal to the use of common species. A rough assessment of locations via screening for potential to profit from halophyte utilisation can be made if basic characteristics of the location and expected plant performance are known. Locations should especially be taken into consideration if halophytes can be used there at very low cost, if there is an urgent need to solve the problem of salinated water resources or soil, or if the current water supply is extremely expensive. Due to the unique characteristics of halophytes, their use shows external effects that differ from the use of common species. They may be positive as well as negative. In any case, they need to be recognised. Especially politicians have to be aware of the benefits halophyte utilisation can deliver to the society and should support the utilisation adequately.
Software has been implemented for this study to facilitate the economic analysis of halophyte utilisation. It applies dynamic methods of investment theory and is designed to keep the number of boundary conditions to a minimum. Examples demonstrate its functionality.
Although several halophytic species are already used successfully, this study makes clear that, in many cases, further dissemination of halophyte utilisation needs more research and field trials for experimentation and demonstration. Most halophytes grow only wild up to now. The potential to improve their characteristics to be used as a crop is immense and should be exploited by scientists. Field trials need to be analysed under economic aspects. Costs and, if applicable, profitability need to be documented. The circumstances of these factors also need to be sufficiently transparent.