TITLE:
Assessment of Flood Disaster Vulnerability, Sustaining Agricultural Productivity and Mitigation of CH4 Emission through Rice-Duck-Fish Mixed Farming Systems across the Dingaputa Haor of Netrokona District, Bangladesh
AUTHORS:
Zidan Ali Fagun, Muhammad Aslam Ali, Shahroz Mahean Haque, Md. Shahadat Hossen, Tanver Hossain, Biddut Kumar Paul, Md. Saimur Rashid, A. B. M. Shafiul Alam, Md. Mozammel Haque, Md. Shamsur Rahman
KEYWORDS:
Flood Vulnerability, Haor Ecosystem, Rice-Duck-Fish Farming, GWPs, Spirulina
JOURNAL NAME:
American Journal of Climate Change,
Vol.15 No.3,
August
28,
2026
ABSTRACT: Dingapota Haor, the low-lying wetland ecosystem in Bangladesh, was found to be mostly vulnerable to natural disasters like flash floods and seasonal floods, which posed severe impacts on agricultural productivity and the economy of the haor community. The flood vulnerability index (FVI) was estimated by incorporating the social, economic, environmental, and physical components. This study highlights a gradual increase in climate-related risks over the past decade, including rising floodwater (VI = 0.63), temperature (VI = 0.76), lightning and thunderstorms (VI = 0.84), hailstorms (VI = 0.58), and rainfall (VI = 0.67), ultimately revealing the total FVI value of 0.95, indicating very high vulnerability of the haor community to flood disaster. The rice-duck-fish mixed farming system trials conducted at different locations in the Dingapota haor revealed the overall superiority of rice-duck and rice-duck-fish farming practices over the traditional rice monoculture system. On average, rice yield was increased by 9.0% - 14.5% and 6.10% - 10.40% under rice-duck-fish and rice-duck mixed farming practices over the rice sole cropping. The mean maximum net return Tk. 308,570/ha, Tk. 198,484/ha, BCR values of 1.8 and 1.7 were obtained from rice-duck-fish and rice-duck mixed farming practices, respectively. The total seasonal CH4 flux was decreased by 19.5%, 15.4%, and 21.0% under rice-duck, rice-fish, and rice-duck-fish mixed farming, respectively, compared to rice sole cropping. The Rice-Duck and Rice-Fish-Duck mixed farming systems reduced GWPs by 15% - 19% and 16% - 20% compared to the rice sole cropping system (5751 - 6156 kg CO2 eq. ha−1). Positive correlations were observed between seasonal cumulative CH4 emissions and floodwater pH, whereas negative correlations were observed with DO, EC, TDS, nitrate, dissolved Fe, Eh, ammonium, and phosphate contents. Conclusively, spirulina-based biofertilizer with half of the conventional inputs application in rice-duck-fish and rice-duck mixed farming systems may be suitable for sustainable agricultural productivity, improving rural economy, and mitigation of GHG emissions as well as GWPs from the haor ecosystem of Bangladesh.