Impact of salinity intrusion on agriculture of Southwest Bangladesh- A review

Abstract

Bangladesh, a deltaic plain covers more than 30% of the cultivable land is in the coastal area. Out of about 1.689 million hectares of coastal land 1.056 million hectares are affected by various degrees of soil salinity. Agricultural land use in these areas is much lower than the country’s average cropping intensity owing to salinity resulting from the accumulation of excess soluble salts. Consequently normal crop production is hampered due to inadequate irrigation water source, unavailability of salt tolerant crop varieties, habited to cultivation local variety, increase climate change related natural disaster, insufficient locally adaptable technologies for mitigating salinity problem. Additionally, decrease cropping intensity with increased salinity environmental hazards in this area specially during rabi season is common phenomenon. As a result, salinity intrusion not only destructs crop yield but also causes a loss of total crop production on highly salt concentrated soil. Thus saline-prone coastal region had a drastic yield loss i.e. approximately average 20-40% in major crops (cereals, potato, pulses, oil seeds, vegetable, species and fruit crops). The dominant cropping pattern of the saline prone areas of southwest Bangladesh is local transplanted Aman followed by HYV Boro rice. Further rice based farming systems are being converted into prawn/shrimp/crab based farming due to salinity accompanied with the disappearance of native fish species both in open and fresh water bodies encompassing decrease livestock production leading to food insecurity. So key impacts of salinization on extent, land feature and crop production along with its credible causes and pathways in south-west Bangladesh are discussed with the recommendations needed.

Keywords: Salinization, cropping intensity, food security, Southwest Bangladesh, Agriculture.