Bangladesh is currently self-sufficient in rice production but faces immense challenges of sustaining that self-sufficiency because of population growth and climate change. There is little scope to further increase cropping intensity except in the underutilized 1.2 Mha of lands enclosed in the polders of the coastal zone. The main impediment to wide-scale adoption of more productive cropping systems in the polders is poor drainage that often results in waterlogging. Therefore, a study was conducted in polder 30, in the medium-salinity region of the south-west coastal zone, to examine the biophysical and economic feasibility of low-cost gravity (gravity-led) drainage. The results show a considerable opportunity to increase rice production in the polders with improved drainage practices. The feasibility of drainage through pumping (energy-fed) was also assessed, given that there are already situations where gravity-led drainage is not feasible, and these situations are likely to increase because of climate change-induced sea level rise and the sinking of polder lands. Energy-fed drainage was demonstrated to be profitable with a yield gain of at least 1.5 t/ha from just the wet season; further intensification to 50% of polder lands may yield an additional harvest of 3–6 million tons of rice per year. Therefore, investing in improved drainage management in the polders could be a major game changer in sustaining the food security of the nation, especially the climate-vulnerable polder communities of Bangladesh.

中文翻译：

---

评估重力引导和能源供给的排水系统以维持孟加拉国沿海地区的粮食安全

孟加拉国目前在稻米生产方面自给自足，但由于人口增长和气候变化，在维持这种自给自足方面面临巨大挑战。除了沿海地区圩田中未充分利用的 1.2 Mha 土地外，几乎没有进一步提高种植强度的空间。在圩田中大规模采用更高产的耕作系统的主要障碍是排水不畅，这通常会导致内涝。因此，在西南沿海地区中等盐度地区的 30 号圩田进行了一项研究，以检验低成本重力（重力引导）排水的生物物理和经济可行性。结果表明，通过改进排水措施来增加圩田水稻产量的机会很大。还评估了通过泵送（能源供给）排水的可行性，因为已经存在重力引导排水不可行的情况，并且由于气候变化引起的海平面上升和海平面下沉，这些情况可能会增加圩田。能源供给排水被证明是有利可图的，仅从雨季就可以增加至少 1.5 吨/公顷的产量；进一步集约化到 50% 的圩田可能每年额外收获 3-6 百万吨大米。因此，投资改善圩田的排水管理可能是维持国家粮食安全的重大改变，尤其是孟加拉国易受气候影响的圩田社区。由于气候变化引起的海平面上升和圩田下沉，这些情况可能会增加。能源供给排水被证明是有利可图的，仅从雨季就可以增加至少 1.5 吨/公顷的产量；进一步集约化到 50% 的圩田可能每年额外收获 3-6 百万吨大米。因此，投资改善圩田的排水管理可能是维持国家粮食安全的重大改变，尤其是孟加拉国易受气候影响的圩田社区。由于气候变化引起的海平面上升和圩田下沉，这些情况可能会增加。能源供给排水被证明是有利可图的，仅从雨季就可以增加至少 1.5 吨/公顷的产量；进一步集约化到 50% 的圩田可能每年额外收获 3-6 百万吨大米。因此，投资改善圩田的排水管理可能是维持国家粮食安全的重大改变，尤其是孟加拉国易受气候影响的圩田社区。进一步集约化到 50% 的圩田可能每年额外收获 3-6 百万吨大米。因此，投资改善圩田的排水管理可能是维持国家粮食安全的重大改变，尤其是孟加拉国易受气候影响的圩田社区。进一步集约化到 50% 的圩田可能每年额外收获 3-6 百万吨大米。因此，投资改善圩田的排水管理可能是维持国家粮食安全的重大改变，尤其是孟加拉国易受气候影响的圩田社区。