Welcome to APSIM


APSIM 7.9 Release

Author: Dean Holzworth/Wednesday, 3 May 2017/Categories: News


Number of views (645)/Comments (0)



APSIM used in over 110 countries

APSIM is now being used in over 110 countries around the world. For the 2016/17 reporting year there were just over 1870 R&D non-commercial licensed users, around a 10% increase on the previous year. This resulted in some 2960 downloads of all versions.
A copy of the APSIM users map is available here.
Thursday, 3 August 2017/Author: Chris Murphy/Number of views (201)/Comments (0)/
Categories: Features

Simulating carbon dioxide fertilisation in crops

To model crop growth under the higher atmospheric carbon dioxide concentrations that will occur in the future, there needs to be and accurate representation of the link between atmospheric carbon dioxide concentrations and growth.

A review of APSIM’s crop models showed that carbon dioxide fertilisation effects were well founded, tested and documented in a number of important (mainly C3 crops) crops, notably wheat. There was agreement that many of these well founded representations could be generalised to other crops with similar photosynthetic pathways (e.g. generalising the science in wheat to other C3 crops). The situation was less well substantiated in crops with the C4 photosynthetic pathway.

The overall conclusion is that for a range of important crops, the general situation of representing carbon dioxide fertilisation effects on photosynthesis and transpiration in APSIM was close to the ‘state of the art’ given current understanding of, and data on the processes involved, and the aims of the APSIM model. There is an immediate need for better documentation of the representation of carbon dioxide fertilisation in APSIM, and a strategic need for further research and model development in this area.

For further details see the new paper titled Responses to atmospheric CO2 concentrations in crop simulation models: a review of current simple and semicomplex representations and options for model development published in Global Change Biology at the following link.

The current status of the representation, parameterisation and validation of CO2 fertilisation of plants in APSIM compiled by Vanuytrecht and Thorburn is also available here.

Wednesday, 29 March 2017/Author: Chris Murphy/Number of views (607)/Comments (0)/
Categories: Features

International Crop Modeling Symposium Shows New Opportunities

More than 300 scientists from 47 nations met in Berlin, Germany, during March 15-17, 2016 to exchange ideas on improvement and application of crop simulation models to better predict agricultural production and food security under global climate change. The symposium was co-organized by MACSUR (Modelling European Agriculture with Climate Change for Food Security, http://macsur.eu/) and AgMIP (Agricultural Model Intercomparison and Improvement Project, http://www.agmip.org/), and was locally hosted by the Leibniz Centre for Agricultural Landscape Research (ZALF) in Müncheberg, Germany.

During the 3-day meeting, there were a total of 85 presentations and 130 poster presentations.  There were plenary lectures by James Jones (University of Florida, USA; The next Generation of Crop Models), Serge Savary (INRA, Toulouse, France; Models for Crop Diseases), Graeme Hammer (University of Queensland, Australia; Modelling and Genetics), Andrew J. Challinor (University of Leeds, UK; Models and Climate), Brian Keating (CSIRO, Australia; Models and Cropping Systems) and Achim Dobermann (Director of Rothamsted Research). Closing plenary lecture was given by Prof. Martin Kropff (Director General of the International Maize and Wheat Improvement Center, CIMMYT).

iCROPM2016 Symposium keynote presentations and abstracts are available at http://communications.ext.zalf.de/sites/crop-modelling/SitePages/Symposium%20Presentations.aspx

Tuesday, 10 May 2016/Author: Chris Murphy/Number of views (2925)/Comments (0)/
Categories: Features

APSIM demonstrates the importance of rotations for simulating climate impact assessments.

In a recently published article Teixeira et al. (http://dx.doi.org/10.1016/j.envsoft.2015.05.012) used APSIM to assess the impact of different methods of representing the initial conditions of the soil.  In climate impact studies, weather data are commonly taken over a 20-30 year period to assess inter-annual variability of crop production.  Often, for simplification, individual crops (monocultures) are sown on the same date every year and soil water and nitrogen are reinitialised to default values prior to planting (re-initialised monoculture). However, in reality crops are often grown in a rotation and the soil conditions they encounter at planting are the result of the water and nitrogen balances of the preceding crops and fallow periods.  APSIM is able to construct realistic rotations and represent carryover effects of crop sequences. Teixeira et al. simulated a continuous wheat (grain) ® wheat (forage) ® kale (forage) ® maize (grain) rotation over a 30 years to compare with re-initialised mono-culture simulations.  The production, water use and soil nitrogen of simulated crops were all sensitive to the method of simulation (re-initialised mono-culture vs. continuous rotation) and the sensitivities were greatest when inputs (water and nitrogen) were lowest. This paper shows that greater emphasis should be placed on obtaining suitable initial conditions for simulating crop production, particularly for low intensity crop production systems.  It is difficult to achieve this in single crop simulations, which illustrates the benefit of representing the carryover of soil conditions across multiple crops grown in a sequence as performed with APSIM in this study.

Wednesday, 9 March 2016/Author: Chris Murphy/Number of views (3970)/Comments (0)/
Categories: Features

Global agricultural systems modelling community convening in Berlin

In March 2016, agricultural systems modellers will meet in Berlin, Germany, for an international symposium, coordinated by scientists from Germany, Finland, Australia and the USA. The agricultural systems modelling network spans the whole globe and more than 300 participants are expected to show up for the event, organized by the Leibniz Centre of Agricultural Landscape Research in Müncheberg, Germany. Crop models have developed into indispensable tools in the ongoing discussion on global food security, but only their consistent application through global co-operation assures their usefulness and credibility at the interfaces of agronomy with economics and in informing policy-making. Additional details can be found on the symposium flyer or website www.icropm2016.org.

Tuesday, 19 January 2016/Author: Chris Murphy/Number of views (4063)/Comments (0)/
Categories: Features