Salt intrusion adaptation measures for sustainable agricultural development under climate change effects: A case of Ca Mau Peninsula, Vietnam

Purpose: The Ca Mau Peninsula, a sub-region of the Vietnamese Mekong Delta, plays an extremely important and decisive role in the country's food security. Due to the influence of complex hydrological regime, annual intrusion of sea water in the dry season has caused barriers and constraints for existing agricultural practices. However, the projection of saline simulation indicated that the occurrence of salt intrusion is likely further inland and severe intensity in the Hau River and coastal areas of the Ca Mau Peninsula in line with the rise of sea levels under climate change effects. This paper aims to propose mitigation and adaptation measures of salt tolerance for sustainable agricultural development in the Ca Mau Peninsula up to 2030 in accordance with projected scenarios of sea level rise. Methodology: The study inherited the results of forecasting salt intrusion in scenarios of sea level rise until 2030 by using the MIKE 11 HD-AD model in a previous research of the authors, in order to suggest mitigation and adaptation measures against salt intrusion for agricultural activities in the Ca Mau Peninsula. The documents relating to salt tolerance of crops, state of irrigation structures and land use were also collected and analyzed to provide more information for better proposed solutions. Findings: The paper presents some feasible measures to mitigate and adapt salt intrusion as sea level rise under impacts of climate change including appropriate land use planning; reasonable shifts in agricultural practices, in particular in the selection of plants and crops which can be tolerant to various salt limits; applying advanced cultivation techniques such as less water irrigation practices of alternate wetting and drying and salt tolerance enhancement; and hard-engineered structures for salt prevention and freshwater conveyance in freshwater-scarce areas. Practical implications: The study will be very meaningful for local farmers in the Ca Mau Peninsula to develop agriculture sustainably, especially, the famers can select crops which are suitable with the salt concentrations or change land use and cultivation models for higher yields. Social implications: The measures proposed in this study will help to increase the efficiency of agricultural production toward a sustainable agriculture-based economy, which will bring sustainable livelihoods for farmers in the peninsula where agriculture and aquaculture are their main economic activities. Originality/value: Until now, mitigation and adaptation measures of salt intrusion in the Ca Mau Peninsula have not been perfected. They were suggested by general view only, and not based upon scientific evidences. This paper gives a system of solutions which were proposed based upon specific evaluation of current and future forecasted salt intrusion scenarios.