Popis: |
Understanding the dynamics of salt movement in the soil is a prerequisite for devising 23 appropriate management strategies for land productivity of coastal regions, especially low lying 24 delta regions which support many millions of farmers around the world. In this research, we 25 develop a novel holistic approach to simulate soil salinization comprising an emulator-based soil 26 salt and water balance calculated at daily time steps. The method is demonstrated for the 27 agriculture areas of Coastal Bangladesh. This shows that we can reproduce the dynamics of soil 28 salinity under multiple land uses, including rice crops, combined shrimp and rice farming, as 29 well as non-rice crops. The model also reproduced well the observed spatial soil salinity for the 30 year 2009. Using this approach, we have projected the soil salinity for three different climate 31 ensembles, including relative sea-level rise for the period 2041-2050. The results indicate an 32 increase in soil salinity in 21-44% of the simulated area. This can potentially cause significant 33 crop yield reductions, especially for vegetables and local rice varieties. The modelling approach 34 will enable planners and land use managers to investigate future trajectories of salinity impacts 35 on crop production, considering expected changes in relative sea level, groundwater pumping 36 and water quality in the rivers and estuary, and management responses to augment freshwater 37 supplies. |