Salinity status of coastal plateau not alarming as yet – study |10 July 2017

The preliminary result of a study to assess the source and severity of the salinity status of the Seychelles coastal plateau, especially at Anse Royale, shows that high salinity exists but not very alarming for coastal farming for the time being.

During the four-day study which started on July 3, soil samples from Anse Royale, Anse à la Mouche and Val D’Andorre were taken for hydro-chemical and stable isotope analysis. The overall results will be made available in four months’ time as further isotopic analysis will be done in Morocco in parallel with the hydro-chemical analysis which will be done locally .

The announcement was made in a press conference by leading water expert from Morocco, Dr Hamid Marah, who is the director for study and scientific research at CNESTEN (Centre National de L’Energie, des Sciences et des Techniques Nucleaires) in Morocco. The press conference was held last Friday at the headquarters of the Ministry of Fisheries and Agriculture, Maison Collet.

With farmers losing their crops from time to time due to salinity, the study was aimed at finding the source and severity of the problem and to find the correct solutions to remedy the situation.

This will also allow the farmers to get all necessary information for them to make calculated decisions on when, where and how to irrigate or if they have to switch to fresh water for irrigation in future.

Farmers from Anse Royale where the main part of the study was done, use underground water which is considered as highly salinated, for irrigation. The farmers can continue with their farming method with this type of water for irrigation but changes in future irrigation methods or systems will be made known following the full report on the study.  

In the presence of the chief executive of the Seychelles Agricultural Agency Finley Racombo and other staff of the agency, Dr Marah explained that the overall results of the study will be made to the authorities in a few more weeks “because we want to make sure that we get to know the correct source of the problem and then propose the best solutions and recommendations so that decision makers can make the good decisions on how to tackle the problem.

“The salinity is not alarming but it will get worse in the future if nothing is done to contain it. This will require huge investment,” Dr Marah said.

He said that the problem of salinity in the soil could be coming from sea water intrusion, dissolution of rocks or from the use of pesticides and fertilisers with high concentration of nitrate.

“Seychelles is not the only country experiencing the salinity problem. All coastal areas around the world are suffering from this problem. In other areas it’s more catastrophic than here as the impact of climate change, the over exploitation, especially for the agriculture industry and these coastal areas are normally vulnerable to this problem of salinity,” Dr Marahsaid, praising the very good communication between agriculture officers and the farmers that helps in addressing agricultural concerns.

Forming part of the local team in the study, principal technologist of the Seychelles Agricultural Agency Barry Nourice said that the salinity study is part of a bigger national project on soil and water management which started in 2014.

He said the early identification of salinity in Seychelles’ coastal areas since 2010 has helped in identifying a major problem which could have a major effect and changes on the land use management as early decision to tackle the problem can be taken.

In the case of Praslin Mr Nourice said the salinity pilot study had already been done on the Cap Samy Plateau with the sponsorship of UNDO GEF small grant programme in collaboration with the Baie St Anne Farmers Association.

“The salinity on Praslin in greater than on Mahé because of limited access to fresh water and the farms are situated close to the sea but we have reintroduced gypsum (a fertiliser containing calcium sulphate) which helps in regulating the ratio of sodium and magnesium in the soil. This is part of the solution for regulating salinity for Praslin farmers for the time being and this solution method is also being used by farmers on Mahé. For this new salinity project, the solutions will be shared with farmers on Praslin and elsewhere,” Mr Nourice said.

He thanked the sponsor of the project, the International Atomic Energy Agency (IAEA) in collaboration with other partners, namely the UNDP GEF Small Grant Programme, for facilitating the study which is still ongoing.