A survey by FAO shows that soil salinity problems are less severe than previously expected. More than two-thirds of the agricultural land damaged by tsunami waves in Indonesia, Sri Lanka, the Maldives, India and Thailand can be used for cultivation this year. Due to the humid conditions in most of the countries surrounding the Indian Ocean, salt-polluted arable land has been cleansed by rainfall and irrigation (FAO, 2005a). However, as for Indonesia, which was the worst hit country by the tsunami, the prospect is more pessimistic. Dr. Anton Apriyantono, Minister of Agriculture, Indonesia, says that the rehabilitation of agricultural areas will take between two and five years due to layers of salty sediments covering part of the 30,000 hectares of tsunami-hit rice fields (Jakarta Post, 2005).

Salinization causes reverse osmosis in soil where higher concentrations of salt draw water from plants' roots, which makes crops wither and sometimes die. While the above two statements are somewhat conflicting, they both agree that in considering a mechanism of recovery from salinization, the critical factor is the availability of water to wash the salt accumulated by the tsunami inundation away. Unlike salinization in arid and semi-arid areas, which is caused by long-term misused of irrigation, salinization by flooded seawater is much easier to treat if sufficient water is available. For example, it is reported that paddy fields mistakenly contaminated with brackish water and the consequent damage to rice production could be recovered through one to three sequential processes of fresh water irrigation, plowing and drainage (Hokkaido, 1991). The amount of water necessary to recover land productivity is determined firstly by the concentration level of salt in the soil, then by various secondary factors such as the chemical and physical characteristics of the soil, the drainage condition of the farmland, the quality of irrigation water, evaporation and the salt tolerance of crops. Previous research results have shown that where farmland is saturated with seawater, the amount of water necessary to recover soil productivity varies between 30 mm and 750 mm, or 300 ton/ha and 7,500 ton/ha. The problem of salinization in tsunami-hit regions might already be solved thanks to heavy rainfall and sufficient irrigation water in some areas, but the problem might be prolonged up to several years on severely damaged rainfed farmland.

FAO has already made a framework for reclamation action plans for tsunami-affected soil, including a classification method of damaged lands and a prescription for reclamation according to the level of damage. One of the reclamation options is to temporarily or permanently diversify the farming system to compensate for the expected losses of food production and income (FAO, 2005b). It should be noted that if it is difficult to acquire sufficient water to reduce salinity levels in the fields, the introduction of crops with higher salt tolerance might be a practical choice. Some secondary crops like soybean or barley are known as highly salt-tolerant crops.

The technical methodology for the rehabilitation of soil productivity is known. The next step will be political support to implement the plans. Policy decisions should be established based on proper understanding of the current situation and future needs in real problem areas. It is important to consider, for example, both short-term recovery and long-term development. The quick recovery of economic activities is vital for the rural poor who lost their means of earning daily income. On the other hand, it is also necessary to look at the whole picture of rural development. We should endeavor not only to recover the damage but also promote more vigorous rural societies, which can overcome vulnerability to natural disaster. The establishment of a reclamation plan for salinization should be based on proper information regarding water resources, farming systems and market structures in the region, which could also be useful to promote sustainable agricultural development. The process of land allocation to reestablish ownership can provide an opportunity to consider proper land policies stimulating farmers to invest in their farmland. We might even consider this rehabilitation process as a positive if the rehabilitation activities succeed in establishing better social security levels and improving rural welfare .

Written by Tomohide Sugino, Project Leader, AGRIDIV Project, UNESCAP-CAPSA, Bogor, Indonesia.

(References available upon request)