Assays

To return Vapour pressure calculated from Wet and Dry Bulb Temperatures. This is a submodel of AFRC Wheat 2 model in Simile notation (the XML version will follow shortly).

Related Publications
Porter J (1993). AFRCWHEAT2: A Model of the Growth and Development of Wheat Incorporating Responses to Water and Nitrogen.. Eur. J. Agron. 2(2): 69-82..

Originally submitted to PLaSMo on 2011-02-04 15:55:57

To return daily thermal time with base TBASE. Thermal time for a day is calculated by splitting the 24 hour period into 8 * 3 hour periods whose relative contribution to thermal time for the day is based on a cosinusoidal variation in temperature between observed maximum and minimum values. See Weir,A.H. et al.,(1984).J.Agric.Sci.,Camb.,102,371-382. This is a submodel of AFRC Wheat 2 model in Simile notation (the XML version will follow shortly).     All variables and parameters that are inputs ...

To calculate today's daylength and photoperiod. Daylength is calculated following the treatment of Sellers, Physical Climatology,pp 15-16 and Appendix 2. Daylength is calculated with a correction for atmospheric refraction equivalent to 50 minutes of a degree. Photoperiod is calculated assuming that light is perceived until the centre of the sun is 6 degrees below the horizon. This is a submodel of AFRC Wheat 2 model in Simile notation (the XML version will follow shortly). All variables and ...

To calculate leaf and sheath dimensions for main stems and tillers given the emergence length of their leaves and empirical relationships linking leaf number to maximum laminar length. All sizes are in mm. This is a submodel of AFRC Wheat 2 model in Simile notation (the XML version will follow shortly). All variables and parameters that are inputs to the submodel are in the "inputs " submodel box, all variables changed by the submodel are outputted via the "outputs" submodel box.Related ...

Transform Calendar day to Julian Day. Converts day, month, year into the equivalent Julian Day allowing for leap years. This is a submodel of AFRC Wheat 2 model in Simile notation (the XML version will follow shortly).Related PublicationsPorter J (1993). AFRCWHEAT2: A Model of the Growth and Development of Wheat Incorporating Responses to Water and Nitrogen. . Eur. J. Agron. 2(2): 69-82.. Originally submitted to PLaSMo on 2011-02-04 15:30:45

Number of days between 2 Julian days allowing for change of year and leap years. Assumptions : The gap between the two dates is less than 1 year also JDAY1 is before JDAY2. This is a submodel of AFRC Wheat 2 model in Simile notation (the XML version will follow shortly).  Related PublicationsPorter J (1993). AFRCWHEAT2: A Model of the Growth and Development of Wheat Incorporating Responses to Water and Nitrogen. . Eur. J. Agron. 2(2): 69-82.. Originally submitted to PLaSMo on 2011-02-04 15:24:25 ...

Penman Evaporation over water ( mm/day ). This is a submodel of AFRC Wheat 2 model in Simile notation (the XML version will follow shortly).

Related Publications
Porter J (1993). AFRCWHEAT2: A Model of the Growth and Development of Wheat Incorporating Responses to Water and Nitrogen. . Eur. J. Agron. 2(2): 69-82..

Originally submitted to PLaSMo on 2011-02-04 15:17:42

"3PG is an acronym for Physiological Principles Predicting Growth. It is a generalized forest carbon allocation model, published by Landsberg and Waring (1997), that works with any forest biome and can be run as an Excel spreadsheet by practicing foresters given a few days of training. The model uses relatively simple and readily available inputs such as species growth tables, latitude, aspect, weather records, edaphic variables, stand age, and stand density to derive monthly estimates of gross ...