Final Technical Report - weADAPT

processes taking place at the land surface - atmosphere interface. A mosaic
representation of land surface cover, and sub grid parameterizations for infiltration
and the spatial variability of precipitation, account for sub-grid scale heterogeneities
in key hydrological processes. The model uses two soil layers and a vegetation layer
with energy and moisture fluxes exchanged between the layers. Vegetation and soil
characteristics associated with each grid cell are reflected in sets of vegetation and
soil parameters. Parameters for vegetation types are specified in a user defined
library of vegetation classes (usually derived from standard, national classification
schemes), while their distribution over the gridded land surface area is specified in a
vegetation parameter file. Soil characteristics (e.g. sand and clay percents, bulk
density) can be represented for a user-defined number of vertical soil layers - usually
two or three, divided into a thin upper layer and a secondary set of layers that extend
several meters into the soil column (Lohman, et al, 1998).
o Study of impact of climate change on rain-fed agriculture in Lower Mekong River
Basin
Crop model was used to simulate future potential yield of rice productivity in the
region under different climate conditions from the scenarios simulated by climate
model. Decision Support System for Agro Technology Transfers (DSSAT version
4.0) crop modeling software (Hoogenboom et al, 1998) was selected as simulation
tool in this. The crop modeling software used daily climate data from the climate
simulation, including maximum and minimum temperature, precipitation, solar
radiation, etc., coupled with crop management scheme and soil property to calculate
potential yield of rice in the study area. By using daily climate data for the simulation
process, this study is able to capture the impact of climate change on rain-fed rice
production not only in terms of the change in degree of intensity of each climate
parameter, e.g. increase or decrease in rainfall or temperature, but also change in
temporal aspect too, e.g. shifting of the onset or changing on the length of raining
season or change in the pattern of mid-season dry spell period, etc.
Final technical report – AIACC AS07 13