Enhancing the performance of Canegro-DSSAT V3.5 model

Code (CO)	MSI03P3941
Author (AU)	Cheeroo-Nayamuth, B. F. Pathack, B.
Title - English (ET)	Enhancing the performance of Canegro-DSSAT V3.5 model
Thesis-Parent title (TH)	ISSCT Agronomy workshop: Opportunities in sugar cane agronomy to confront the new realities emerging in the 21st century, 21-25 July 2003, MSIRI, Mauritius: Program and Abstracts
Document Type(DT)	book chapter
Date of publication (DP)	2003
Source (SO)	p. 41
Publisher (PB)	Reduit: ISSCT and Mauritius Sugar Industry Research Institute
Language of text (LT)	En
Language of summaries (LS)	En
Abstract (AB)	Crop modeling, a discipline that is being increasingly accepted as a cost-effective support to conventional agricultural research, requires reliable weather data for precise evapotranspiration estimates within simulation exercises. The DSSAT V3.5 simulation platform allows the computation of evapotranspiration by different means, namely, the Richie Modification of the Priestley-Taylor method that requires daily minimum and maximum temperatures, rainfall and solar radiation and the Penman-Monteith option, a more accurate method that requires in addition windrun and dewpoint temperature. Since dewpoint temperature is not measured, a program was developed in FORTRAN for its calculation from recorded wet-bulb and dry-bulb temperatures using the Clasius-Claperon method combined with the psychrometer equation. Simulations were run with the validated Canegro model to assess the importance of weather parameters on the evapotranspiration estimates by the two above methods and to evaluate their impacts on cane yield of variety R 570 grown from 1991 to 1998 under water regimes ranging from rainfed to full water requirements at Tamarin. The regression of simulated on observed dry cane yield range of 3 t/ha to 55 t/ha, showed that the best simulations were obtained when the dewpoint temperature and windrun data were specified and the Penman-Monteith evapotranspiration method was adopted. When windrun and dewpoint data were not used, the Richie Modification of the Priestley-Taylor option resulted in an underestimation of 10. 9 t/ha of dry cane while the Penman-Monteith option resulted in an underestimation of 5.9 t/ha. The importance of using real time dewpoint temperature and windrun in modeling studies and the evapotranspiration estimate to be adopted are demonstrated.
Descriptors - English (DE)	Evapotranspiration modeling sugarcane
Descriptors - Geographic (DG)	Mauritius
Sort Key 1(K1)	Sugarcane: Physiology
Sort Key 2 (K2)	Modeling
Date record entered (DA)	2003-07-31
Language of analysis (LA)	En
Affiliation (AF)	MSIRI
Location (LO)	LIB
MSIRI Staff (MS)	LRD