Building Salinity-resilient Agriculture

Salinity is spreading at an alarming rate across the southwestern region of Bangladesh, posing a serious threat to agriculture, food security, and the livelihoods of millions of people. According to the Soil Salinity Map of Bangladesh 2024 prepared by the Soil Resources Development Institute (SRDI), around 68 per cent of the cultivable land in 18 of the country’s 19 coastal districts is now affected by varying degrees of salinity. The problem extends beyond soil, as groundwater salinity is also increasing, creating long-term risks for agricultural production. The latest SRDI assessment reveals that of the 1.703 million hectares of cultivable land in the southwestern region, about 1.156 million hectares were affected by salinity in 2024, compared with 1.056 million hectares in 2009.  In just 15 years, an additional 100,000 hectares of agricultural land have become saline-- an area nearly equal to the size of Munshiganj district. The first national survey conducted in 1973 recorded 833,000 hectares of saline land, indicating a continuous expansion over the past five decades. It has been found that both the extent and intensity of salinity are increasing. So, without effective intervention, agricultural production and national food security will face serious challenges.
Bangladesh’s coastal region covers nearly one-third of the country’s land area and is home to approximately 43.8 million people. Farmers in this region are already experiencing declining crop yields, shortages of safe drinking water, and deteriorating livelihoods. As agricultural land continues to shrink due to urbanisation and other competing land uses, increasing salinity places even greater pressure on food production. The updated salinity map shows that Kashiani and Muksudpur in Gopalganj district, previously considered non-saline, along with Jessore Sadar, have entered the salinity zone for the first time. Experts also warn that continued sea-level rise could expose areas such as Alfadanga in Faridpur and Mohammadpur in Magura to salinity in the future.
The spread of salinity is driven by both natural and human-induced factors. Climate change, sea-level rise, cyclones, tidal surges, and irregular rainfall have intensified saltwater intrusion. Human interventions have further aggravated the situation. The coastal embankment projects implemented during the 1960s disrupted natural tidal flows, causing saline water to become trapped in many areas. Poor maintenance of sluice gates and drainage systems has reduced freshwater flushing, allowing salinity to persist. Another major factor is the reduced dry-season freshwater flow from upstream rivers following the commissioning of the Farakka Barrage in 1975. Rivers such as the Gorai-Madhumati and Kapotaksha now receive less freshwater, enabling saline water to penetrate further inland. In contrast, much of the Barisal region remains comparatively less affected because of continued freshwater flow through the Padma and lower Meghna rivers.
The rapid expansion of saline shrimp farming has also accelerated soil salinization. Over the past four decades, large areas of paddy fields have been converted into shrimp ponds. In many cases, embankments were cut to allow saline water into the ponds, unintentionally spreading salinity to adjacent agricultural land. SRDI data indicate that saline-affected land increased by about 22.5 percent between 1973 and 2000. Although the rate of expansion slowed between 2000 and 2009, it accelerated again during 2009–2024. Over the past five decades, nearly 323,000 hectares of previously non-saline agricultural land have become saline. Around 10 percent of the affected land now falls into the "very high salinity" category, where cultivation of most conventional crops is extremely difficult.
Professor M A Sattar Mandal, former Vice-Chancellor of Bangladesh Agricultural University, notes that Bangladesh’s arable land has declined from about 9 million hectares to nearly 8 million hectares over the last two decades. Combined with increasing land fragmentation and salinity, this trend threatens long-term agricultural productivity. Climate projections further suggest that continued sea-level rise could push salinity even farther inland, placing greater pressure on food production, farmers' incomes, and rural livelihoods.
To address these growing challenges, SRDI recommends improving soil and crop management, expanding salt-tolerant crop varieties, promoting high-yielding varieties tolerant to salinity and waterlogging during the Aus and Aman seasons, and developing integrated agro-fishery systems. 
The institute also emphasises river restoration, rainwater harvesting, regulated groundwater use, rehabilitation of sluice gates and polders, and strengthening salinity monitoring and forecasting systems. Ensuring adequate upstream freshwater flow through effective transboundary water cooperation is equally important.
Apart from introducing salt-tolerant technologies, improved management practices must be extended to the farmers quickly through stronger agricultural extension services and effective coordination among research institutions, policymakers and local communities.
Given the rapid inland expansion of salinity, coastal agriculture should be treated as a national food security priority. The government should consider implementing a long-term integrated master plan for salinity-prone areas, supported by dedicated budget allocations. 
Greater investment is needed in research, seed production of salt-tolerant varieties, climate-smart irrigation, freshwater conservation, river and canal restoration, farmer-friendly credit, crop insurance, and incentives for climate-resilient farming. Integrated agriculture–fishery–livestock production systems should also be promoted to diversify income and strengthen resilience.
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The writer is Principal Scientific Officer at BARI. He can be reached at [email protected]