69 

DSSAT

 

ABSTRACT 

Climate change affects all agriculture activities. When long-term climate pattern has 

changed, the weather factors, such as temperature and rainfall, might affect the quality 
and quantity of crop growth. Paddy rice is the most important crop productions in Taiwan 
and accounts for more than 70% of total water resources usage. The quantity of rice 
productions is a very important index for food security and agriculture management. This 
study utilizes the Decision Support System for Agrotechnology Transfer (DSSAT) model 
to analyze the variations of growth days and quantity of paddy rice under climate change. 
The Weather Generator Model (WGEN) was used to generate daily rainfall and daily 
mean temperature. Maximum and minimum daily temperature and solar radiation were 
then estimated by regression functions of daily mean temperature and daily rainfall from 
historical data. Rice productions were estimated by the DSSAT model. The Taiwan 
Climate Change Projection and Information Platform Project (TCCIP) provides future 
climate projections and the A1B scenarios of Special Report on Emissions Scenarios were 
selected in this study. To understand the dominant factors affecting crop yields under 
climate change, the Principal Component Analysis(PCA) was applied to analyze DSSAT 
results for both periods of baseline data (1985~1990) and near future data (2020~2039). 
Accumulated solar radiation, accumulated growing degree, crop water requirement and 
growing days were retrieved for performing PCA. Climate variations projected by 
ensemble models and CM3 model showed accumulated growing degree before blossom is 
the most important factor, while in MK3_0 mode is the accumulated solar radiation 
before blossom. 

Keywords: Climate Change, Rice, DSSAT, PCA. 

 

 

 

1.1  

(2012)