Evaluating the Effects of Salinity Changes on Farming Patterns in Salt-contaminated Land Areas in Can Giuoc District Under the Impacts of Climate Change Using Hydrus 1d Model

The Mekong Delta is currently being strongly affected by climate change, especially in the coastal estuaries. In the dry season, the tide intrudes deeply into the inland, causing salinization of water resources and soils, affecting agricultural cultivation. In addition, the restructuring of crops and failed aquaculture have polluted a large number of areas that are difficult to recover. This study aims to evaluate the influence of salinity changes on different farming models by using the 1D Hydrus simulation model to find a reasonable farming solution on the natural conditions of the area. Testing simulated salinity data with observed data in 2017 of Land Use Type 1(LUT1) according to the simulated data shows a generally good agreement to observed data for Land Use Type 1 (LUT1), indicated by a relatively good coefficient of determination (R2 = 0.78) and the Nash Sutcliffe Error (NSE = 0.73). The calibrated model parameters were used to simulate salinity under eight different scenarios that consider the effects of climate change and sea level rise. The salinity occurred in the root layer (0 - 20cm) of LUT2 affecting salinity tolerance of plant in KB5 (current scenario). Input data (soil profile, Hydro-meteorological data…) of 05 selected samples were processed by using the Rosetta program of the USDA to estimate values of Van Genuchten parameters. The results can be a basis for proposing effective agricultural land use solutions such as: rice-shrimp (focusing on cropping time schedule) in less saline areas, or high technology agriculture (without using directly land resource and basing on only land surface in the case study.